Synopsis
Narratives are common to all branches of science, not only to the humanities. Scientists tell stories about how the things we study work, develop, and evolve, and about how we come to be interested in them. Here I add a third domain (Secularity) to Gould's two "non-overlapping magisteria" of Science and Religion, and I review previous work on the parallels in elements between story-telling in literature and science. The stories of each domain have different criteria for judging them valid or useful. In science, especially historical sciences such as biology and geology, particular scientific methods and approaches both structure and test our narratives. Relying on the narrative assumptions of how certain processes, such as natural selection, are supposed to work is treacherous unless they are tested by appropriate historical patterns, such as phylogeny, and rooted in the process of natural mechanisms. The structure of scientific explanation seen in peer-reviewed papers and grant proposals obscures true narrative within a formulaic sequence of "question, methods, materials" and so on that is quite different from the classic narrative of folk-tales and novels, producing an "anti-narrative" that must be "un-learned" before it can be communicated to non-scientists. By adopting some of the techniques of classic story-telling, scientists can become more effective in making our ideas clear, educating the public, and even attracting funding.Δευτέρα 4 Ιουνίου 2018
The Mitochondrial Basis for Adaptive Variation in Aerobic Performance in High-Altitude Deer Mice
Synopsis
Mitochondria play a central role in aerobic performance. Studies aimed at elucidating how evolved variation in mitochondrial physiology contributes to adaptive variation in aerobic performance can therefore provide a unique and powerful lens to understanding the evolution of complex physiological traits. Here, we review our ongoing work on the importance of changes in mitochondrial quantity and quality to adaptive variation in aerobic performance in high-altitude deer mice. Whole-organism aerobic capacity in hypoxia (VO2max) increases in response to hypoxia acclimation in this species, but high-altitude populations have evolved consistently greater VO2max than populations from low altitude. The evolved increase in VO2max in highlanders is associated with an evolved increase in the respiratory capacity of the gastrocnemius muscle. This appears to result from highlanders having more mitochondria in this tissue, attributed to a higher proportional abundance of oxidative fibre-types and a greater mitochondrial volume density within oxidative fibres. The latter is primarily caused by an over-abundance of subsarcolemmal mitochondria in high-altitude mice, which is likely advantageous for mitochondrial O2 supply because more mitochondria are situated adjacent to the cell membrane and close to capillaries. Evolved changes in gastrocnemius phenotype appear to be underpinned by population differences in the expression of genes involved in energy metabolism, muscle development, and vascular development. Hypoxia acclimation has relatively little effect on respiratory capacity of the gastrocnemius, but it increases respiratory capacity of the diaphragm. However, the mechanisms responsible for this increase differ between populations: lowlanders appear to adjust mitochondrial quantity and quality (i.e., increases in citrate synthase [CS] activity, and mitochondrial respiration relative to CS activity) and they exhibit higher rates of mitochondrial release of reactive oxygen species (ROS), whereas highlanders only increase mitochondrial quantity in response to hypoxia acclimation. In contrast to the variation in skeletal muscles, the respiratory capacity of cardiac muscle does not appear to be affected by hypoxia acclimation and varies little between populations. Therefore, evolved changes in mitochondrial quantity and quality make important tissue-specific contributions to adaptive variation in aerobic performance in high-altitude deer mice.Shape, size, and structure affect obliquely striated muscle function in squid
Abstract
Hollow, cylindrical body plans and obliquely striated muscles are characteristic of soft-bodied invertebrates, and both affect the biomechanics of movement in these diverse animals. We highlight two different aspects of functional heterogeneity in obliquely striated muscles, one driven by animal shape and size and the other by the intrinsic mechanical properties of the fibers. First, we show how a hollow, cylindrical shape in the mantle of cephalopod molluscs causes a significant difference in muscle strain (defined as the change in length divided by resting length) across the mantle wall, and describe the implications of such "transmural gradients of strain" for the length-tension relationship of the obliquely striated muscles that power movements in these animals. We show that transmural gradients of strain increase in magnitude as mantle wall proportions change during ontogeny, with the relatively thin mantle walls of newly hatched squid experiencing significantly smaller differences in strain than the thicker mantle walls of adults. Second, we describe how the length-tension relationship of obliquely striated mantle muscles varies with position to accommodate the transmural gradient of strain, with the result that circular muscle fibers near the inner and outer surfaces of the mantle are predicted to produce similar force during mantle contraction. The factors that affect the length-tension relationship in obliquely striated muscles are unknown, and thus we have not yet identified the mechanism(s) responsible for the transmural shift in the length-tension properties of the mantle circular fibers. We have, however, developed a mathematical model that predicts small changes in the oblique striation angle (which varies from 4 to 12° in adult squid) have a significant effect on the shape of the length-tension relationship, with lower angles predicted to result in a broader length-tension curve.Impact of age on the efficacy of oxaliplatin in the preoperative chemoradiotherapy and adjuvant chemotherapy of rectal cancer: A post hoc analysis of the CAO/ARO/AIO-04 phase 3 trial
Abstract
Background
The German rectal cancer trial CAO/ARO/AIO-04 has shown a significant benefit in 3-year disease-free survival (DFS) of adding oxaliplatin to a standard preoperative 5-fluorouracil-based chemoradiotherapy (CRT) and adjuvant chemotherapy in patients with locally advanced rectal cancer. The use of oxaliplatin as adjuvant treatment in elderly patients with colon cancer is controversial . We therefore investigated the impact of age on clinical outcome in the CAO/ARO/AIO-04 phase 3 trial. Patients and Methods
We performed a post hoc analysis of the CAO/ARO/AIO-04 phase 3 trial evaluating primary and secondary endpoints according to age. Patient and tumor characteristics, adverse events grades of 3-4, dose intensities as well as survival and recurrence data were analyzed in three specified age groups (<60, 60-70, and ≥70 years). The influence of age as a continuous variable on DFS was modeled using a subpopulation treatment effect pattern plot (STEPP) analysis. Results
A total of 1,232 patients were evaluable. With the exception of ECOG status (p < 0.001), no differences in patient and tumor characteristics were noticed between age groups. Likewise, toxicity pattern, dose intensities of CRT and surgical results were similar in all age groups. After a median follow-up of 50 months, in patients aged <60 years a significant benefit of adding oxaliplatin to 5-FU-based CRT and adjuvant chemotherapy was observed for local (p = 0.013) and systemic recurrences (p = 0.023), DFS (p = 0.011) and even overall survival (OS; p = 0.044. The STEPP analysis revealed improved hazard ratios for DFS in patients aged 40-70 years compared with elderly patients treated with oxaliplatin. Conclusion
The addition of oxaliplatin significantly improved DFS and OS in younger patients aged <60 years with advanced rectal cancer. Patients aged ≥70 years had no benefit. Clinical Trials Number
NCT00349076Non-rigid registration of 3D ultrasound for neurosurgery using automatic feature detection and matching
Abstract
Purpose
The brain undergoes significant structural change over the course of neurosurgery, including highly nonlinear deformation and resection. It can be informative to recover the spatial mapping between structures identified in preoperative surgical planning and the intraoperative state of the brain. We present a novel feature-based method for achieving robust, fully automatic deformable registration of intraoperative neurosurgical ultrasound images.
Methods
A sparse set of local image feature correspondences is first estimated between ultrasound image pairs, after which rigid, affine and thin-plate spline models are used to estimate dense mappings throughout the image. Correspondences are derived from 3D features, distinctive generic image patterns that are automatically extracted from 3D ultrasound images and characterized in terms of their geometry (i.e., location, scale, and orientation) and a descriptor of local image appearance. Feature correspondences between ultrasound images are achieved based on a nearest-neighbor descriptor matching and probabilistic voting model similar to the Hough transform.
Results
Experiments demonstrate our method on intraoperative ultrasound images acquired before and after opening of the dura mater, during resection and after resection in nine clinical cases. A total of 1620 automatically extracted 3D feature correspondences were manually validated by eleven experts and used to guide the registration. Then, using manually labeled corresponding landmarks in the pre- and post-resection ultrasound images, we show that our feature-based registration reduces the mean target registration error from an initial value of 3.3 to 1.5 mm.
Conclusions
This result demonstrates that the 3D features promise to offer a robust and accurate solution for 3D ultrasound registration and to correct for brain shift in image-guided neurosurgery.
Migration and transformation of different phosphorus forms in rainfall runoff in bioretention system
Abstract
Artificial bioretention system consisting of Ophiopogon japonicus infiltration medium was used to simulate an infiltration experiment of rainfall runoff. Continuous extraction method was used to detect contents of inorganic phosphorus (P) under exchangeable state (Ex-P) and aluminium phosphate (Al–P) and iron phosphate (Fe–P) at different depths (0, 5, 15 and 35 cm) of soil infiltration medium in bioretention system. Effluent total P (TP) concentration of the system was also monitored. Results indicated that the adsorption of inorganic P, Al–P and Fe–P by soil infiltration medium was implemented layer by layer from top to bottom and gradually weakened. Moreover, Ex-P was gradually transformed into Al–P and Fe–P, whereas Al–P was gradually transformed into Fe–P; thus, Ex-P content reduced layer by layer, whereas Al–P and Fe–P gradually accumulated. The TP removal rate in runoff rainwater by the system was more than 90%, where the TP that was not used by plants was under dynamic equilibrium in water–soil–root system/biological system.
Evaluation of the influence of economic groups on the efficiency and quality of service of water companies: an empirical approach for Chile
Abstract
The privatization of water and sewerage services (WSS) has led to the foundation of water economic groups, which integrate several water companies and have gained notable importance at the global level. In the framework of benchmarking studies, there are no prior studies exploring the impact that economic groups have on the efficiency and quality of service provided by water companies. This study investigates, for the first time, whether the membership of water companies in an economic group influences their performance. Quantity- and quality-adjusted efficiency scores were computed using data envelopment analysis models. An empirical application was developed for the Chilean water industry since most of their water companies are private and belong to an economic group. The results show that independent water companies provide WSS with better quality than do water companies that belong to an economic group. From a statistical point of view, it was evident that membership in an economic group impacts both the quantity- and quality-adjusted efficiency scores of water companies. The results of this study illustrate that applying the model-firm regulation to the Chilean water industry has significant drawbacks that should be addressed by the water regulator to promote the long-term sustainability of the water industry.
Persulfate activation with rice husk-based magnetic biochar for degrading PAEs in marine sediments
Abstract
Phthalate esters (PAEs) can interfere with the endocrine systems of humans and wildlife. The main objective of this study was to evaluate the suitability of a composite for remediating marine sediments contaminated with PAEs. The composite was synthesized with magnetite nanoparticles (Fe3O4) and rice husk biochar (RHB) by using chemical co-precipitation. Fe3O4, RHB, and Fe3O4–RHB substantially activated sodium persulfate (Na2S2O8, PS) oxidation to form SO4−• and thus degrade PAEs in marine sediments in a slurry system. The morphology and structural composition of the magnetic composites were examined using XRD, FTIR, environmental scanning electron microscopy–energy-dispersive X-ray spectrometry, and superconducting quantum interference device. The Fe3O4–RHB composites were confirmed to be prepared successfully. The influences of various parameters, including the PS concentration, composite loading, and initial pH, were investigated. The concentration of high-molecular-weight PAEs (HPAEs) in sediment was much higher than that of low-molecular-weight PAEs (LPAEs); di-(2-ethylhexyl) phthalate (DEHP) was an especially salient marker of PAE contamination in sediments. Furthermore, increasing the PS and Fe3O4–RHB doses accelerated PAE oxidation at pH 3.0; 83% degradation of PAEs was achieved when the PS and Fe3O4–RHB concentrations were increased to 2.3 × 10−2 mM and 1.67 g/L, respectively. LPAEs such as dibutyl phthalate (DnBP) are easier to degrade than HPAEs such as DEHP, diisononyl phthalate (DINP), and diisodecyl phthalate (DIDP). In addition, possible activation mechanisms of the interactions between S2O82− and Fe2+/Fe3+ on the Fe3O4 surface, which involve an efficient electron transfer mediator of the RHB oxygen functional groups promoting the generation of SO4−• in the Fe3O4–RHB/PS system, were clarified. Thus, the Fe3O4–RHB/PS oxidation process is expected to be a viable method for remediating PAE-contaminated marine sediment.
Visual grading analysis of digital neonatal chest phantom X-ray images: Impact of detector type, dose and image processing on image quality
Abstract
Objectives
To evaluate the impact of digital detector, dose level and post-processing on neonatal chest phantom X-ray image quality (IQ).
Methods
A neonatal phantom was imaged using four different detectors: a CR powder phosphor (PIP), a CR needle phosphor (NIP) and two wireless CsI DR detectors (DXD and DRX). Five different dose levels were studied for each detector and two post-processing algorithms evaluated for each vendor. Three paediatric radiologists scored the images using European quality criteria plus additional questions on vascular lines, noise and disease simulation. Visual grading characteristics and ordinal regression statistics were used to evaluate the effect of detector type, post-processing and dose on VGA score (VGAS).
Results
No significant differences were found between the NIP, DXD and CRX detectors (p>0.05) whereas the PIP detector had significantly lower VGAS (p< 0.0001). Processing did not influence VGAS (p=0.819). Increasing dose resulted in significantly higher VGAS (p<0.0001). Visual grading analysis (VGA) identified a detector air kerma/image (DAK/image) of ~2.4 μGy as an ideal working point for NIP, DXD and DRX detectors.
Conclusions
VGAS tracked IQ differences between detectors and dose levels but not image post-processing changes. VGA showed a DAK/image value above which perceived IQ did not improve, potentially useful for commissioning.
Key points
• A VGA study detects IQ differences between detectors and dose levels.
• The NIP detector matched the VGAS of the CsI DR detectors.
• VGA data are useful in setting initial detector air kerma level.
• Differences in NNPS were consistent with changes in VGAS.
Utility of MRI for cervical spine clearance in blunt trauma patients after a negative CT
Abstract
Purpose
To determine the utility of cervical spine MRI in blunt trauma evaluation for instability after a negative non-contrast cervical spine CT.
Methods
A review of medical records identified all adult patients with blunt trauma who underwent CT cervical spine followed by MRI within 48 h over a 33-month period. Utility of subsequent MRI was assessed in terms of findings and impact on outcome.
Results
A total of 1,271 patients with blunt cervical spine trauma underwent both cervical spine CT and MRI within 48 h; 1,080 patients were included in the study analysis. Sixty-six percent of patients with a CT cervical spine study had a negative study. Of these, the subsequent cervical spine MRI had positive findings in 20.9%; 92.6% had stable ligamentous or osseous injuries, 6.0% had unstable injuries and 1.3% had potentially unstable injuries. For unstable injury, the NPV for CT was 98.5%. In all 712 patients undergoing both CT and MRI, only 1.5% had unstable injuries, and only 0.42% had significant change in management.
Conclusions
MRI for blunt trauma evaluation remains not infrequent at our institution. MRI may have utility only in certain patients with persistent abnormal neurological examination.
Key Points
• MRI has limited utility after negative cervical CT in blunt trauma.
• MRI is frequently positive for non-specific soft-tissue injury.
• Unstable injury missed on CT is infrequent.
Could IVIM and ADC help in predicting the KRAS status in patients with rectal cancer?
Abstract
Purpose
To evaluate the diagnostic potential of DW-MRI relative parameters for differentiation of rectal cancers with different Kirsten rat sarcoma viral oncogene homologue (KRAS) mutation status.
Methods
Fifty-one patients with rectal cancer underwent diffusion-weighted MR imaging with eight b values. ADCs (including Max-ADC, Min-ADC and Mean-ADC) and IVIM parameters (D, pure diffusion; f, perfusion fraction; D*, pseudodiffusion coefficient) were respectively calculated by mono- and bi-exponential analysis. Patients were stratified into two groups: KRAS wild type and mutant. The DW-MRI-derived parameters between the KRAS wild-type group and KRAS mutant group were compared using the Mann-Whitney U test. Receiver-operating characteristic (ROC) analysis of discrimination between KRAS wild-type and KRAS mutant rectal cancer was performed for the DW-MRI-derived parameters.
Results
Max-ADC, Mean-ADC and D values were significantly lower in the KRAS mutant group than in the KRAS wild-type group, whereas a higher D* value was demonstrated in the KRAS mutant group. According to the ROC curve, Mean-ADC and D* values showed moderate diagnostic significance with the AUC values of 0.756 and 0.710, respectively. The cut-off values for Mean-ADC and D* were 1.43 × 10-3mm2/s and 26.58 × 10-3mm2/s, respectively.
Conclusion
Rectal cancers had distinctive diffusion/perfusion characteristics in different KRAS mutation statuses. The DW-MRI-derived parameters, specifically Mean-ADC and D*, show a moderate diagnostic significance for KRAS status.
Key Points
• Rectal cancers with different KRAS mutation statuses demonstrated distinctive diffusion/perfusion characteristics.
• Max-ADC, Mean-ADC and D values were lower in the KRAS mutant group.
• A higher D* value was demonstrated in the KRAS mutant group.
• IVIM-DW MRI may potentially help preoperative KRAS mutant status prediction.
Staging liver fibrosis with DWI: is there an added value for diffusion kurtosis imaging?
Abstract
Objectives
To assess liver fibrosis in patients with chronic liver disease using diffusion kurtosis imaging (DKI) in comparison with conventional diffusion-weighted imaging, with histology as reference standard.
Methods
This prospective study included 81 patients and DKI with b-values of 0, 200, 500, 1,000, 1,500, 2,000 s/mm2 were performed. Mean diffusivity (MD), mean kurtosis (MK) and apparent diffusion coefficient (ADC) maps were calculated. The diagnostic efficacy of MD, MK and ADC for predicting stage 2 fibrosis or greater, and stage 3 fibrosis or greater were compared.
Results
The MD (rho=-0.491, p<0.001), MK (rho=0.537, p<0.001) and ADC (rho=-0.496, p<0.001) correlated significantly with fibrosis stages, and ADC exhibited a strong negative correlation with MK (rho=-0.968; p<0.001) and a moderate association with MD (rho=0.601, p<0.001). Areas under the curves (AUCs) for predicting stage 2 fibrosis or greater were not significantly different (p>0.05) between MK (0.809) and ADC (0.797) as well as between MD (0.715) and ADC. AUCs were also similar for MD (0.710), MK (0.768) and ADC (0.747) for predicting stage 3 fibrosis or greater.
Conclusion
Although DKI is feasible for predicting liver fibrosis in patients with chronic liver disease, MD and MK offer similar diagnostic performance to ADC values.
Key Points
• Diffusion kurtosis imaging is feasible for staging liver fibrosis.
• Diffusion kurtosis and monoexponential model are highly correlated.
• The kurtosis model offers no added value to the conventional, monoexponential model
Leveraging the coronary calcium scan beyond the coronary calcium score
Abstract
Non-contrast cardiac computed tomography in order to obtain the coronary artery calcium score has become an established diagnostic procedure in the clinical setting, and is commonly employed in clinical and population-based research. This state-of-the-art review paper highlights the potential gain in information that can be obtained from the non-contrast coronary calcium scans without any necessary modifications to the scan protocol. This includes markers of cardio-metabolic health, such as the amount of epicardial fat and liver fat, but also markers of general health including bone density and lung density. Finally, this paper addresses the importance of incidental findings and of radiation exposure accompanying imaging with non-contrast cardiac computed tomography. Despite the fact that coronary calcium scan protocols have been optimized for the visualization of coronary calcification in terms image quality and radiation exposure, it is important for radiologists, cardiologists and medical specialists in the field of preventive medicine to acknowledge that numerous additional markers of cardio-metabolic health and general health can be readily identified on a coronary calcium scan.
Key Points
• The coronary artery calcium score substantially increased the use of cardiac CT.
• Cardio-metabolic and general health markers may be derived without changes to the scan protocol.
• Those include epicardial fat, aortic valve calcifications, liver fat, bone density, and lung density.
• Clinicians must be aware of this potential additional yield from non-contrast cardiac CT.
Accelerated real-time cardiac MRI using iterative sparse SENSE reconstruction: comparing performance in patients with sinus rhythm and atrial fibrillation
Abstract
Objectives
To compare accelerated real-time cardiac MRI (CMR) using sparse spatial and temporal undersampling and non-linear iterative SENSE reconstruction (RT IS SENSE) with real-time CMR (RT) and segmented CMR (SEG) in a cohort that included atrial fibrillation (AF) patients.
Methods
We evaluated 27 subjects, including 11 AF patients, by acquiring steady-state free precession cine images covering the left ventricle (LV) at 1.5 T with SEG (acceleration factor 2, TR 42 ms, 1.8 × 1.8 × 6 mm3), RT (acceleration factor 3, TR 62 ms, 3.0 × 3.0 × 7 mm3), and RT IS SENSE (acceleration factor 9.9-12, TR 42 ms, 2.0 × 2.0 × 7 mm3). We performed quantitative LV functional analysis in sinus rhythm (SR) patients and qualitatively scored image quality, noise and artefact using a 5-point Likert scale in the complete cohort and AF and SR subgroups.
Results
There was no difference between LV functional parameters between acquisitions in SR patients. RT IS SENSE short-axis image quality was superior to SEG (4.5 ± 0.6 vs. 3.9 ± 1.1, p = 0.007) and RT (3.8 ± 0.4, p = 0.003). There was reduced artefact in RT IS SENSE compared to SEG (4.4 ± 0.6 vs. 3.8 ± 1.2, p = 0.04), driven by arrhythmia performance. RT IS SENSE short-axis image quality was superior to SEG (4.6 ± 0.5 vs. 3.1 ± 1.0, p < 0.001) in the AF subgroup.
Conclusion
Accelerated real-time CMR with iterative sparse SENSE provides excellent clinical performance, especially in patients with AF.
Key Points
• Iterative sparse SENSE significantly accelerates real-time cardiovascular MRI acquisitions.
• It provides excellent qualitative and quantitative performance in sinus rhythm patients.
• It outperforms standard segmented acquisitions in patients with atrial fibrillation.
• It improves the trade-off between temporal and spatial resolution in real-time imaging.
Contrast-enhanced cadaver-specific computed tomography in gross anatomy teaching
Abstract
Objectives
To establish contrast-enhanced (CE) cadaver-specific post-mortem computed tomography (PMCT) in first-year gross anatomy teaching and quantitatively evaluate its learning benefit.
Methods
132 first-year medical students were included in this IRB-approved study and randomly assigned to an intervention group (n=59) provided with continuous access to CE and non-enhanced (NE) cadaver-specific PMCT-scans during the first-semester gross anatomy course, and a control group (n=73) that had only NE cadaver-specific PMCT data available. Four multiple-choice tests were carried out (15 questions each) subsequent to completion of the corresponding anatomy module: Head and neck anatomy, extremities, thorax, and abdomen. Median test results were compared in each module between the groups using the Wilcoxon rank-sum test. Additionally, participants of the intervention group answered a 15-item feedback-questionnaire.
Results
The intervention group achieved significantly higher test scores in head and neck anatomy (median=12.0, IQR=10.0–13.0) versus the control group (median=10.5, IQR=9.0–12.0) (p<0.01). There were no significant differences in the comparison of other modules. CEPMCT was highly appreciated by undergraduate medical students.
Conclusions
The incorporation of contrast-enhanced cadaver-specific PMCT-scans in gross anatomy teaching was proven to be feasible in the framework of the medical curriculum and significantly improved the students' learning performance in head and neck anatomy.
Key Points
• Cadaver-specific contrast-enhanced post-mortem CT (CEPMCT) is feasible in the medical curriculum.
• CEPMCT yields significantly improved learning performance in head and neck anatomy (p<0.01).
• CEPMCT is highly appreciated by medical students and used in tutor- or self-guided modes.
DNA double-strand breaks in blood lymphocytes induced by two-day 99m Tc-MIBI myocardial perfusion scintigraphy
Abstract
Objectives
To investigate DNA double-strand breaks (DSBs) in blood lymphocytes induced by two-day 99mTc-MIBI myocardial perfusion scintigraphy (MPS) using y-H2AX immunofluorescence microscopy and to correlate the results with 99mTc activity in blood samples.
Methods
Eleven patients who underwent two-day MPS were included. DSB blood sampling was performed before and 5min, 1h and 24h after the first and second radiotracer injections. 99mTc activity was measured in each blood sample. For immunofluorescence microscopy, distinct foci representing DSBs were quantified in lymphocytes after staining for the phosphorylated histone variant y-H2AX.
Results
The 99mTc-MIBI activity measured on days one and two was similar (254±25 and 258±27 MBq; p=0.594). Compared with baseline DSB foci (0.09±0.05/cell), a significant increase was found at 5min (0.19±0.04/cell) and 1h (0.18±0.04/cell) after the first injection and at 5min and 1h after the second injection (0.21±0.03 and 0.19±0.04/cell, respectively; p=0.003 for both). At 24h after the first and second injections, the number of DSB foci had returned to baseline (0.06±0.02 and 0.12±0.05/cell, respectively). 99mTc activity levels in peripheral blood samples correlated well with DSB counts (r=0.451).
Conclusions
DSB counts reflect 99mTc-MIBI activity after injection for two-day MPS, and might allow individual monitoring of biological effects of cardiac nuclear imaging.
Key Points
• Myocardial perfusion scintigraphy using 99mTc induces time-dependent double-strand breaks (DSBs)
• γ-H2AX immunofluorescence microscopy shows DSB as an early response to radiotracer injection
• Activity measurements of 99mTc correlate well with detected DSB
• DSB foci induced by 99mTc return to baseline 24h after radiotracer injection
Radiomic signature as a diagnostic factor for histologic subtype classification of non-small cell lung cancer
Abstract
Objectives
To distinguish squamous cell carcinoma (SCC) from lung adenocarcinoma (ADC) based on a radiomic signature
Methods
This study involved 129 patients with non-small cell lung cancer (NSCLC) (81 in the training cohort and 48 in the independent validation cohort). Approximately 485 features were extracted from a manually outlined tumor region. The LASSO logistic regression model selected the key features of a radiomic signature. Receiver operating characteristic curve and area under the curve (AUC) were used to evaluate the performance of the radiomic signature in the training and validation cohorts.
Results
Five features were selected to construct the radiomic signature for histologic subtype classification. The performance of the radiomic signature to distinguish between lung ADC and SCC in both training and validation cohorts was good, with an AUC of 0.905 (95% confidence interval [CI]: 0.838 to 0.971), sensitivity of 0.830, and specificity of 0.929. In the validation cohort, the radiomic signature showed an AUC of 0.893 (95% CI: 0.789 to 0.996), sensitivity of 0.828, and specificity of 0.900.
Conclusions
A unique radiomic signature was constructed for use as a diagnostic factor for discriminating lung ADC from SCC. Patients with NSCLC will benefit from the proposed radiomic signature.
Key points
• Machine learning can be used for auxiliary distinguish in lung cancer.
• Radiomic signature can discriminate lung ADC from SCC.
• Radiomics can help to achieve precision medical treatment.
Editorial comment: the future of compositional MRI for cartilage
Abstract
This editorial comment refers to the article: "Detection of early cartilage damage: feasibility and potential of gagCEST imaging at 7T" by Brinkhof et al, Eur Radiol 2018.
Analytical derivation of elasticity in breast phantoms for deformation tracking
Abstract
Purpose
Patient-specific biomedical modeling of the breast is of interest for medical applications such as image registration, image guided procedures and the alignment for biopsy or surgery purposes. The computation of elastic properties is essential to simulate deformations in a realistic way. This study presents an innovative analytical method to compute the elastic modulus and evaluate the elasticity of a breast using magnetic resonance (MRI) images of breast phantoms.
Methods
An analytical method for elasticity computation was developed and subsequently validated on a series of geometric shapes, and on four physical breast phantoms that are supported by a planar frame. This method can compute the elasticity of a shape directly from a set of MRI scans. For comparison, elasticity values were also computed numerically using two different simulation software packages.
Results
Application of the different methods on the geometric shapes shows that the analytically derived elongation differs from simulated elongation by less than 9% for cylindrical shapes, and up to 18% for other shapes that are also substantially vertically supported by a planar base. For the four physical breast phantoms, the analytically derived elasticity differs from numeric elasticity by 18% on average, which is in accordance with the difference in elongation estimation for the geometric shapes. The analytic method has shown to be multiple orders of magnitude faster than the numerical methods.
Conclusion
It can be concluded that the analytical elasticity computation method has good potential to supplement or replace numerical elasticity simulations in gravity-induced deformations, for shapes that are substantially supported by a planar base perpendicular to the gravitational field. The error is manageable, while the calculation procedure takes less than one second as opposed to multiple minutes with numerical methods. The results will be used in the MRI and Ultrasound Robotic Assisted Biopsy (MURAB) project.
Halotolerant plant-growth promoting rhizobacteria modulate gene expression and osmolyte production to improve salinity tolerance and growth in Capsicum annum L.
Abstract
Some rhizobacteria have demonstrated a noteworthy role in regulation of plant growth and biomass production under biotic and abiotic stresses. The present study was intended to explicate the ameliorative consequences of halotolerant plant growth-promoting rhizobacteria (HPGPR) on growth of capsicum plants subjected to salt stress. Salt stress was ascertained by supplementing 1 and 2 g NaCl kg−1 soil. The HPGPR positively invigorated growth attributes, chlorophyll, protein contents, and water use efficiency (WUE) of supplemented capsicum plants under salinity stress conditions. Bacillus fortis strain SSB21 caused highest significant increase in shoot length, root length, and fresh and dry biomass production of capsicum plants grown under saline conditions. This multi-trait bacterium also increased biosynthesis of proline and up-regulated the expression profiles of stress related genes including CAPIP2, CaKR1, CaOSM1, and CAChi2. On the other hand, B. fortis strain SSB21 inoculated plants exhibited reduced level of ethylene, lipid peroxidation, and reactive oxygen species (ROS). All these together contribute to activate physiological and biochemical processes involved in the mitigation of the salinity induced stress in capsicum plants.
Twelve-Year Trajectories of Sitting Time are Associated With Frailty in Middle-Aged Women
Abstract
Prolonged sitting time is associated with several health outcomes; with limited evidence reporting associations with frailty. The aims of this study were to identify patterns of sitting time over 12 years in middle-aged women and examine associations of these patterns with frailty in older age. Our study examined 5,462 women born in 1946–1951 from the Australian Longitudinal Study on Women's Health who self-reported socio-demographic attributes, daily sitting time and frailty in 2001, and then every three years until 2013. Frailty was assessed using the FRAIL scale (score 0 = healthy; 1–2 = pre-frail; 3–5 = frail) and group-based trajectory analyses identified trajectories of sitting time. We identified five sitting time trajectories: low (27.5%); medium (41.5%; reference); increasing (8.2%); decreasing (18.0%); and high (4.9%). In adjusted models, the likelihoods (odds ratio: 95% confidence interval) of being frail were statistically higher for those in the increasing (1.29: 1.03, 1.61) and high (1.42: 1.10, 1.84) trajectories. In contrast, the low (0.86: 0.75, 0.98) trajectory group was less likely to be frail, with no difference in likelihood of frailty in the decreasing trajectory group. Our study suggests that patterns of sitting time over 12 years in middle-aged women predict frailty in older age.Biomarker-Calibrated Total Sugars Intake and Risk of Type 2 Diabetes and Cardiovascular Disease in the Women's Health Initiative Observational Study
Abstract
The inconsistent findings from epidemiologic studies relating total sugars (TS) consumption to cardiovascular disease (CVD) or type 2 diabetes (T2D) risk may be partly due to measurement error (ME) in self-reported intake. Using regression calibration equations developed based on the predictive biomarker for TS and recovery biomarker for energy, we examined the association of TS with T2D and CVD risk, before and after dietary calibration, in 82,254 postmenopausal women of the Women's Health Initiative-Observational Study. After up to 16 years of follow-up (1993–2010), 6,621 T2D and 5,802 CVD incident cases were identified. The hazard ratio (HR) for T2D per 20% increase in calibrated TS was 0.94 (95% CI: 0.77, 1.15) in multivariable energy substitution (ES), and 1.00 (0.85, 1.18) in energy partition (EP) models. Multivariable HRs for total CVD were 0.97 (0.87, 1.09) from ES, and 0.91 (0.80, 1.04) from EP models. Uncalibrated TS generated a statistically significant inverse association with T2D and total CVD risk in both multivariable ES and EP models. The lack of conclusive findings from our calibrated analyses may be due to the low explanatory power of the calibration equations for TS, which could have led to incomplete deattenuation of the risk estimates.Impact of tryptophan on the formation of TCNM in the process of UV/chlorine disinfection
Abstract
Low-pressure (LP) UV treatment after chlorine disinfection was associated with enhanced formation of trichloronitromethane (TCNM), a halonitromethane disinfection by-product (DBP), due to the chlorination of tryptophan. Evidence was found that the concentration of TCNM from tryptophan increased quickly to the maximum for the first instance. Moreover, the increase of TCNM under UV exceeded 10 times than under dark. Then, it was found to have an obvious decrease in the formation of TCNM, even finally hardly disappear. In order to elucidate reasons for this phenomenon, the effects of light intensity, initial tryptophan concentration, free chlorine concentration, pH, and tert-butanol (TBA) on the formation of TCNM were investigated under UV/chlorine treatment. Finally, the effects of tryptophan on the formation of TCNM and the direct photodegradation of TCNM under LP UV irradiation were studied for analyzing the possible pathways of TCNM formation from amino acid. Since amino acids are very common in water sources, further research into chemical oxidation of these species by LP UV and chlorine is recommended. It can help us to find the precursors of TCNM formation and reduce the risk of TCNM formation for drinking water and wastewater utilities.
Κυριακή 3 Ιουνίου 2018
Temozolomide and irinotecan (TEMIRI regimen) as salvage treatment of irinotecan-sensitive advanced colorectal cancer patients bearing MGMT methylation
Abstract
Background
Non-randomized studies showed that temozolomide (TMZ) achieves an average 10% response rate in heavily pretreated metastatic colorectal cancer (mCRC) patients with promoter methylation of the DNA repair gene O6-methylguanine-DNA methyltransferase (MGMT). In this phase II trial, irinotecan and temozolomide (TEMIRI) combination regimen was assessed in irinotecan-sensitive, MGMT methylated/microsatellite stable (MSS) pretreated mCRC patients. Patients and methods
Key inclusion criteria were: centrally confirmed MGMT methylation by methylation-specific PCR, MSS mCRC, progression after at least two prior chemotherapy regimens for advanced disease and irinotecan-free interval (IFI) >3 months. TEMIRI (TMZ 150mg/sqm on days 1-5 plus irinotecan 100mg/sqm on days1,15 q28 days) was administered for six cycles, followed by maintenance with TMZ. The primary endpoint was overall response rate (ORR). Exploratory translational analyses included MGMT immunoistochemistry (IHC) and methylBEAMing (MB). Results
Between December 2014 and June 2017, 25 patients were enrolled. The primary endpoint was met, since 6 patients achieved a partial response (ORR 24%, 95% CI, 11%-43%). At a median follow-up of 15.6 months, median progression-free survival (mPFS) and overall survival (mOS) were 4.4 and 13.8 months, respectively. Only 4 (16%) patients had ≥ grade 3 adverse events. All patients whose cancer was MGMT-positive IHC were non-responders. Consistently, patients with MGMT-negative/low tumors had a significantly longer mPFS than others (6.9 versus 2.0 months; HR = 0.29, 95%CI, 0.02-0.41; p = 0.003) and a non-significant trend for longer mOS. MB testing showed similar accuracy. Conclusions
TEMIRI regimen is a safe and active option in pre-treated, irinotecan-sensitive mCRC patients with MGMT methylation.Validation of the Complexity INdex in SARComas prognostic signature on formalin-fixed, paraffin-embedded, soft tissue sarcomas
Abstract
Background
Prediction of metastatic outcome in sarcomas is challenging for clinical management since they are aggressive and carry a high metastatic risk. A 67-gene expression signature, the Complexity INdex in SARComas (CINSARC), has been identified as a better prognostic factor than the reference pathological grade. Since it cannot be applied easily in standard laboratory practice, we assessed its prognostic value using nanoString on formalin-fixed, paraffin-embedded (FFPE) blocks to evaluate its potential in clinical routine practice and guided therapeutic management. Methods
A code set consisting of 67 probes derived from the 67 genes of the CINSARC signature was built and named NanoCind®. To compare the performance of RNA-seq and nanoString (NanoCind®), we used expressions of various sarcomas (n=124, frozen samples) using both techniques and compared predictive values based on CINSARC risk groups and clinical annotations. We also used nanoString on FFPE blocks (n=67) and matching frozen and FFPE samples (n=45) to compare their level of agreement. Metastasis-free survival and agreement values in classification groups were evaluated. Results
CINSARC strongly predicted metastatic outcome using nanoString on frozen samples (HR = 2.9, 95% CI 1.23-6.82) with similar risk-group classifications (86%). While more than 50% of FFPE blocks were not analyzable by RNA-seq owing to poor RNA quality, all samples were analyzable with nanoString. When similar (risk-group) classifications were measured with frozen tumors (RNA-seq) compared to FFPE blocks (84% agreement), the CINSARC signature was still a predictive factor of metastatic outcome with nanoString on FFPE samples (HR = 4.43, 95% CI 1.25-15.72). Conclusion
CINSARC is a material-independent prognostic signature for metastatic outcome in sarcomas and outperforms histological grade. Unlike RNA-seq, nanoString is not influenced by the poor quality of RNA extracted from FFPE blocks. The CINSARC signature can potentially be used in combination with nanoString (NanoCind®) in routine clinical practice on FFPE blocks to predict metastatic outcome.Mimickers of Urticaria: Urticarial Vasculitis and Autoinflammatory Diseases
Publication date: Available online 2 June 2018
Source:The Journal of Allergy and Clinical Immunology: In Practice
Author(s): Mark D.P. Davis, Jeroen C.H. van der Hilst
A wide differential diagnosis must be considered in a patient presenting with urticarial plaques. Although acute and chronic urticaria are the commonest diagnoses, other differential diagnoses include polymorphous eruption of pregnancy, mast cell disorders, hypereosinophilic syndrome, urticarial vasculitis, pemphigoid, systemic lupus erythematosus, and autoinflammatory disease. This review will specifically address urticarial vasculitis and autoinflammatory syndromes. These entities represent contrasting examples of urticarial-like lesions resulting from either an adaptive immune complex–mediated mechanism (urticarial vasculitis) or an innate immune–mediated mechanism (autoinflammatory disorders), with differing therapeutic implications. In patients presenting with painful, persistent plaques that last more than 24 hours and resolve with bruising of the skin, consideration should be given to a diagnosis of urticarial vasculitis. A biopsy should be obtained to ascertain this diagnosis. In patients presenting with a persistent history of recurrent urticarial plaques associated with signs of systemic inflammation including fevers and elevated inflammatory markers (C-reactive protein [CRP]/serum amyloid A, leukocytosis, and negative connective tissue serologies), consideration should be given to autoinflammatory disorders: the 3 cryopyrin-associated periodic syndromes, Schnitzler syndrome, and familial cold autoinflammatory syndrome 2. Serum protein electrophoresis should be checked to rule out an underlying monoclonal gammopathy.
Consenso multidisciplinar sobre prevención y tratamiento de la tuberculosis en pacientes candidatos a tratamiento biológico. Adaptación al paciente dermatológico
Publication date: Available online 2 June 2018
Source:Actas Dermo-Sifiliográficas
Author(s): P. Rodríguez-Jiménez, I. Mir-Viladrich, P. Chicharro, G. Solano-López, F.J. López-Longo, C. Taxonera, P. Sánchez-Martínez, X. Martínez-Lacasa, M. García-Gasalla, J. Dorca, M. Arias-Guillén, J.M. García-García, E. Dauden
El riesgo de infección por Mycobacterium tuberculosis se halla aumentado en los pacientes con enfermedades inflamatorias crónicas y en tratamiento inmunosupresor, en particular con terapia antifactor de necrosis tumoral α. La detección de la infección tuberculosa latente y el tratamiento preventivo dirigido a reducir el riesgo de progresión a tuberculosis activa es obligatoria en este grupo de pacientes. Este documento de consenso multidisciplinar actualiza la opinión de expertos y establece recomendaciones para el diagnóstico y tratamiento de la infección tuberculosa latente en estos pacientes, según los conocimientos actuales en terapias biológicas.Patients with chronic inflammatory diseases being treated with immunosuppressive drugs, and with tumor necrosis factor inhibitors in particular, have an increased risk of infection by Mycobacterium tuberculosis. Screening for latent tuberculosis infection and preventive therapy to reduce the risk of progression to active tuberculosis are mandatory in this group of patients. This updated multidisciplinary consensus document presents the latest expert opinions on the treatment and prevention of tuberculosis in candidates for biologic therapy and establishes recommendations based on current knowledge relating to the use of biologic agents.
Comparative study of Gram-negative bacteria response to solar photocatalytic inactivation
Abstract
Solar photocatalytic inactivation of Gram-negative bacteria with immobilized TiO2-P25 in a fixed-bed reactor was modeled with simplified kinetic equations. The kinetic parameters are the following: the photocatalytic inactivation coefficient (kd,QUV), the initial bacterial reduction rate (A) in the contact with the disinfecting agent, and the threshold level of damage (n) were determined to report the effect of QUV/TiO2-P25 on bacterial cultivability and viability and to compare the response of bacterial strains to photocatalytic treatment. In addition, the integration of the reactivation coefficient (Cr) in the photocatalytic inactivation equation allowed evaluating the ability of bacterial reactivation after photocatalytic stress. Results showed different responses of the bacteria strains to photocatalytic stress and the ability of certain bacterial strains such as Escherichia coli ATCC25922 and Pseudomonas aeruginosa ATCC4114 to resuscitate after photocatalytic treatment.
Σάββατο 2 Ιουνίου 2018
Herbicides in vineyards reduce grapevine root mycorrhization and alter soil microorganisms and the nutrient composition in grapevine roots, leaves, xylem sap and grape juice
Abstract
Herbicides are increasingly applied in vineyards worldwide. However, not much is known on potential side effects on soil organisms or on the nutrition of grapevines (Vitis vinifera). In an experimental vineyard in Austria, we examined the impacts of three within-row herbicide treatments (active ingredients: flazasulfuron, glufosinate, glyphosate) and mechanical weeding on grapevine root mycorrhization; soil microorganisms; earthworms; and nutrient concentration in grapevine roots, leaves, xylem sap and grape juice. The three herbicides reduced grapevine root mycorrhization on average by 53% compared to mechanical weeding. Soil microorganisms (total colony-forming units, CFU) were significantly affected by herbicides with highest CFUs under glufosinate and lowest under glyphosate. Earthworms (surface casting activity, density, biomass, reproduction) or litter decomposition in soil were unaffected by herbicides. Herbicides altered nutrient composition in grapevine roots, leaves, grape juice and xylem sap that was collected 11 months after herbicide application. Xylem sap under herbicide treatments also contained on average 70% more bacteria than under mechanical weeding; however, due to high variability, this was not statistically significant. We conclude that interdisciplinary approaches should receive more attention when assessing ecological effects of herbicides in vineyard ecosystems.
The effect of anthropogenic activities on the phosphorus-buffering intensity of the two contrasting rivers in northern China
Abstract
The phosphorus (P)-buffering ability of suspended particulate matter (SPM) from the Ziya River Mainstream (ZRM) and the Luanhe River (LR) of northern China was investigated in this study. Forty samples of SPM from the ZRM and LR were collected in October and November of 2016. The ZRM has slow flow and poor water quality, while the LR has fast flow and reasonably good water quality. Under a scanning electron microscope, the SPM from the ZRM had a more complex microstructure than that from the LR, perhaps because of the slower flow and heavier pollution in the ZRM. P fractions in both SPM and water samples were determined using standard measurement and testing program methods. The equilibrium P concentration was used to determine the influence of SPM on soluble reactive P (SRP) concentrations. These SRP fractions were used to evaluate the P-buffering intensity of the two rivers. Differences in SPM microstructure resulted in the SPM from ZRM having a stronger P-buffering ability than the LR, making SPM an effective vector for SRP. Anthropogenic activities likely contributed to the differences in both microstructures of the SPM and P-buffering intensity of the rivers. A conceptual model was developed to show how anthropogenic activities influence the P-buffering intensity of the two rivers. As far as we know, this is the first time that the P-buffering intensity has been compared between two rivers that have been severely impacted by anthropogenic activities. Our findings provide an important reference for similar rivers worldwide.
Is skewed income distribution good for environmental quality? A comparative analysis among selected BRICS countries
Abstract
A large number of studies have examined the linkage between income inequality and environmental quality at the individual country levels. This study attempts to examine the linkage between the two factors for the individual BRICS economies from a comparative perspective, which is scarce in the literature. It examines the selected countries (Brazil, India, China and South Africa) by endogenising the patterns of primary energy consumption (coal use and petroleum use), total primary energy consumption, economic growth, and urbanisation as key determining factors in CO2 emission function. The long-run results based on ARDL bounds testing revealed that income inequality leads to increase in CO2 emissions for Brazil, India and China, while the same factor leads to reduction in CO2 emissions for South Africa. However, it observes that while coal use increases CO2 emissions for India, China and South Africa, it has no effect for Brazil. In contrast, the use of petroleum products contributes to CO2 emissions in Brazil, while the use of the same surprisingly results in reduction of carbon emissions in South Africa, India and China. The findings suggest that given the significance of income inequality in environmental pollution, the policy makers in these emerging economies have to take into consideration the role of income inequality, while designing the energy policy to achieve environmental sustainability.
Phthalate exposure as a risk factor for hypertension
Abstract
Phthalates are ubiquitous in environment. Hypertension is a major risk factor for cardiovascular diseases. Phthalate exposure is associated with hypertension in multiple studies. This review aims to summarize the scientific literature on associations between phthalate exposure and hypertension and discuss the mechanisms in the relationship. We identified and reviewed original articles published to March 2018, using PubMed and Web of Science to search the terms "phthalate(s)," "phthalic acid," "blood pressure," "high blood pressure," "hypertension," "prehypertension," and "cardiovascular disease." Findings were summarized based on the relevance to the themes, including presentation of main phthalates and their major metabolites as well as associations of phthalate exposure with blood pressure in epidemiological and experimental studies. We identified ten population-based investigations and five toxicological experiments. Epidemiological data underscored a possible correlation between phthalate exposure and hypertension in adults, whereas individual study in children stands on the opposite. Experimental studies mainly targeted the increasing effect of phthalates on blood pressure. This review suggested some underlying mechanisms of phthalate-associated hypertension. Considering the current evidence, phthalate might be risk factors of hypertension. However, the effect of phthalate exposure in early life on blood pressure in later life or adulthood is still unclear. Well-designed longitudinal and molecular mechanism studies are indispensable.
Spent MgO-carbon refractory bricks as a material for permeable reactive barriers to treat a nickel- and cobalt-contaminated groundwater
Abstract
Spent magnesia (MgO)-carbon refractory bricks were repurposed as a permeable reactive barrier reactive media to treat a nickel (5 mg l−1)- and cobalt (0.3 mg l−1)-contaminated groundwater. MgO has been used for decades as a heavy metal precipitating agent as it hydrates and buffers the pH in a range of 8.5–10 associated with the minimum solubility of various divalent metals. The contaminated groundwater site's conditions are typical of contaminated neutral drainage with a pH of 6 as well as high concentrations of iron (220 mg l−1) and sulphates (2500 mg l−1). Using synthetic contaminated water, batch and small-scale column tests were performed to determine the treatment efficiency and longevity. The increase and stabilization of the pH at 10 observed during the tests are associated with the hydration and dissolution of the MgO and promoted the removal not only of a significant proportion of the contaminants but also of iron. During the column test, this accumulation of precipitates over time clogged and passivated the MgO resulting in a loss of chemical performance (pH lowering, metal breakthrough) after 210 pore volumes of filtration. Precipitation also affected the hydraulic conductivity values which dropped from 2.3·10−3 to 4.2·10−4 m s−1 at the end of test. Saturation indices and XRD analyses suggest the precipitates formed are likely composed of goethite as well as iron, cobalt and nickel hydroxides. Recycled MgO-C refractory bricks were demonstrated to be an efficient reactive material for the removal of Co and Ni, but careful considerations should be taken of the potential clogging and passivation phenomena given particular physicochemical conditions.
Anthropogenic CO 2 emissions from a megacity in the Yangtze River Delta of China
Abstract
Anthropogenic CO2 emissions from cities represent a major source contributing to the global atmospheric CO2 burden. Here, we examined the enhancement of atmospheric CO2 mixing ratios by anthropogenic emissions within the Yangtze River Delta (YRD), China, one of the world's most densely populated regions (population greater than 150 million). Tower measurements of CO2 mixing ratios were conducted from March 2013 to August 2015 and were combined with numerical source footprint modeling to help constrain the anthropogenic CO2 emissions. We simulated the CO2 enhancements (i.e., fluctuations superimposed on background values) for winter season (December, January, and February). Overall, we observed mean diurnal variation of CO2 enhancement of 23.5~49.7 μmol mol−1, 21.4~52.4 μmol mol−1, 28.1~55.4 μmol mol−1, and 29.5~42.4 μmol mol−1 in spring, summer, autumn, and winter, respectively. These enhancements were much larger than previously reported values for other countries. The diurnal CO2 enhancements reported here showed strong similarity for all 3 years of the study. Results from source footprint modeling indicated that our tower observations adequately represent emissions from the broader YRD area. Here, the east of Anhui and the west of Jiangsu province contributed significantly more to the anthropogenic CO2 enhancement compared to the other sectors of YRD. The average anthropogenic CO2 emission in 2014 was 0.162 (± 0.005) mg m−2 s−1 and was 7 ± 3% higher than 2010 for the YRD. Overall, our emission estimates were significantly smaller (9.5%) than those estimated (0.179 mg m−2 s−1) from the EDGAR emission database.
Converting environmental risks to benefits by using spent coffee grounds (SCG) as a valuable resource
Abstract
Coffee is perhaps one of the most vital ingredients in humans' daily life in modern world. However, this causes the production of million tons of relevant wastes, i.e., plastic cups, aluminum capsules, coffee chaff (silver skin), and spent coffee grounds (SCG), all thrown untreated into landfills. It is estimated that 1 kg of instant coffee generates around 2 kg of wet SCG; a relatively unique organic waste stream, with little to no contamination, separated directly in the source by the coffee shops. The produced waste has been under researchers' microscope as a useful feedstock for a number of promising applications. SCG is considered a valuable, nutrients rich source of bioactive compounds (e.g., phenolics, flavonoids, carotenoids, lipids, chlorogenic and protocatechuic acid, melanoidins, diterpenes, xanthines, vitamin precursors, etc.) and a useful resource material in other processes (e.g., soil improver and compost, heavy metals absorbent, biochar, biodiesel, pellets, cosmetics, food, and deodorization products). This paper aims to provide a holistic approach for the SCG waste management, highlighting a series of processes and applications in environmental solutions, food industry, and agricultural sector. Thus, the latest developments and approaches of SCG waste management are reviewed and discussed.
Nanostructured catalysts applied to degrade atrazine in aqueous phase by heterogeneous photo-Fenton process
Abstract
SBA-15 and KIT-6 materials have been synthesized and modified with iron salts by the wet impregnation method with different metal loadings. The different mesostructures obtained were characterized by N2 adsorption–desorption at 77 K, X-ray diffraction, temperature-programmed reduction, and ultraviolet–visible spectroscopy. These iron-containing mesostructured materials have been successfully tested for the heterogeneous photo-Fenton degradation of aqueous solutions of dangerous herbicides, such as atrazine, using UV–visible light irradiation, at room temperature and close to neutral pH. The results showed that the Fe/SBA-15 (10%) and Fe/KIT-6 (5%) catalysts exhibited the highest activities. However, the Fe/KIT-6 (5%) catalyst with minor Fe loading than Fe/SBA-15 (10%) presented a higher degradation of atrazine (above 98% in a reaction time of 240 min). Therefore, the interconnectivity of the cage-like mesopores had an important influence on the catalytic activity, favoring probably mass-transfer effects. Thus, the high performance of these materials indicates that the heterogeneous via of photo-Fenton process can also be efficiently employed to treat wastewaters containing pollutants such as herbicides, in order to reduce them to simplest and less toxic molecules.
Bismuth vanadate-based semiconductor photocatalysts: a short critical review on the efficiency and the mechanism of photodegradation of organic pollutants
Abstract
The number of publications on photocatalytic bismuth vanadate-based materials is constantly increasing. Indeed, bismuth vanadate is gaining stronger interest in the photochemical community since it is a solar-driven photocatalyst. However, the efficiency of BiVO4-based photocatalyst under sunlight is questionable: in most of the studies investigating the photodegradation of organic pollutants, only few works identify the by-products and evaluate the real efficiency of BiVO4-based materials. This short review aims to (i) present briefly the principles of photocatalysis and define the photocatalytic efficiency and (ii) discuss the formation of reactive species involved in the photocatalytic degradation process of pollutants and thus the corresponding photodegradation mechanism could be determined. All these points are developed in a comprehensive discussion by focusing especially on pure, doped, and composite BiVO4. Therefore, this review exhibits a critical overview on different BiVO4-based photocatalytic systems with their real efficiency. This is a necessary knowledge for potential implementation of BiVO4 materials in environmental applications at larger scale than laboratory conditions.
Wintertime characteristic of peroxyacetyl nitrate in the Chengyu district of southwestern China
Abstract
Atmospheric concentrations of peroxyacetyl nitrate (PAN) were measured in Ziyang in December 2012 to provide basic knowledge of PAN in the Chengyu district and offer recommendations for air pollution management. The PAN pollution was relatively severe in Ziyang in winter, with the maximum and average PAN concentrations of 1.61 and 0.55 ppbv, respectively, and a typical single-peak diurnal trend in PAN and theoretical PAN lost by thermal decomposition (TPAN) were observed. PAN and O3 concentrations were correlated (R2 = 0.52) and the ratios of daily maximum PAN to O3 ([PAN]/[O3] ratio) ranged from 0.013 to 0.108, with an average of 0.038. Both acetone and methyl ethyl ketone (MEK) were essential for producing the acetylperoxy radicals (PA) and subsequently PAN in Ziyang in winter, and PAN concentrations at the sampling site exhibited more sensitivity to volatile organic compound (VOC) concentrations than nitrogen oxide (NOx) levels. Therefore, management should focus on reducing VOCs emissions, in particular those that produce acetone and MEK through photolysis and oxidizing reactions. In addition, the influence of relative humidity (RH) on the heterogeneous reactions between PAN and PM2.5 in the atmospheric environment may have led to the strong correlation between observed PM2.5 and PAN in Ziyang in winter. Furthermore, a typical air pollution event was observed on 17–18 December 2012, which Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) and PSCF simulations suggest that it was caused by the local formation and the regional transport of polluted air masses from Hanzhong, Nanchong, and Chengdu.
Boosting the catalytic activity of natural magnetite for wet peroxide oxidation
Abstract
This work explores the modification of naturally occurring magnetite by controlled oxidation (200–400 °C, air atmosphere) and reduction (300–600 °C, H2 atmosphere) treatments with the aim of boosting its activity in CWPO. The resulting materials were fully characterized by XRD, XPS, TGA, TPR, SEM, and magnetization measurements, allowing to confirm the development of core-shell type structures. The magnetite core of the solid remained unchanged upon the treatment whereas the Fe(II)/Fe(III) ratio of the shell was modified (e.g. 0.42, 0.11 and 0.63 values were calculated for pristine Fe3O4, Fe3O4-O400, and Fe3O4-R400, respectively). The performance of the catalysts was tested in the CWPO of sulfamethoxazole (SMX) (5 mg L−1) under ambient conditions and circumneutral pH (pH0 = 5), using the stoichiometric dose of H2O2 (25 mg L−1) and a catalyst load of 1 g L−1. The key role of the ferrous species on the mineral shell was evidenced. Whereas the oxidation of magnetite led to significantly slower degradation rates of the pollutant, its reduction gave rise to a dramatic increase, achieving the complete removal of SMX in 1.5 h reaction time with the optimum catalyst (Fe3O4-R400) compared to the 3.5 h required with the pristine mineral. A reaction mechanism was proposed for SMX degradation, and a kinetic equation based on the Eley-Rideal model was accordingly developed. This model successfully fitted the experimental results. The stability of Fe3O4-R400 was evaluated upon five sequential runs. Finally, the versatility of the catalytic system was proved in real environmentally relevant water matrices.
CFD modeling of a UV-A LED baffled flat-plate photoreactor for environment applications: a mining wastewater case
Abstract
The use of ultraviolet light in photoreactors for wastewater treatment has become popular as an alternative of known chemical oxidative substances. UV LED light represents cheaper, robust, and versatile alternative to traditional UV lamps. In this study, it was designed and evaluated a photoreactor with an approach of chemical fluid dynamics (CFD) and experimental validation. The evaluation consisted of (1) CFD velocity profile analysis, (2) characterization of the average light distribution with potassium ferrioxalate actinometry, (3) degradation of a typical recalcitrant metallic cyanocomplex Fe(CN)63−, and (4) scavenger effect analysis in the photodegradation using potassium persulfate. Actinometrical essay concluded that the system was able to receive 1.93 μE/s. The reactor operated under turbulent regime and best result for Fe(CN)63− degradation was obtained at 4 h of operation, using 5-W UV-A LEDs, with pH ~ 7 and 10 mM de S2O82−. Baffled photoreactor demonstrated to be useful for this type of illumination and wastewater treatment.
A pre-operative planning framework for global registration of laparoscopic ultrasound to CT images
Abstract
Purpose
Laparoscopic ultrasound (LUS) enhances the safety of laparoscopic liver resection by enabling real-time imaging of internal structures such as vessels. However, LUS probes can be difficult to use, and many tumours are iso-echoic and hence are not visible. Registration of LUS to a pre-operative CT or MR scan has been proposed as a method of image guidance. However, the field of view of the probe is very small compared to the whole liver, making the registration task challenging and dependent on a very accurate initialisation.
Methods
We propose the use of a subject-specific planning framework that provides information on which anatomical liver regions it is possible to acquire vascular data that is unique enough for a globally optimal initial registration. Vessel-based rigid registration on different areas of the pre-operative CT vascular tree is used in order to evaluate predicted accuracy and reliability.
Results
The planning framework is tested on one porcine subject where we have taken 5 independent sweeps of LUS data from different sections of the liver. Target registration error of vessel branching points was used to measure accuracy. Global registration based on vessel centrelines is applied to the 5 datasets. In 3 out of 5 cases registration is successful and in agreement with the planning. Further tests with a CT scan under abdominal insufflation show that the framework can provide valuable information in all of the 5 cases.
Conclusions
We have introduced a planning framework that can guide the surgeon on how much LUS data to collect in order to provide a reliable globally unique registration without the need for an initial manual alignment. This could potentially improve the usability of these methods in clinic.
3D MRI in Musculoskeletal Imaging: Current and Future Applications
Abstract
Purpose of Review
This article addresses current clinical applications, recent literature, and potential future applications of 3-dimensional magnetic resonance imaging (3D MRI) for musculoskeletal (MSK) applications.
Recent Findings
The main advantage of 3D MRI over standard 2-dimensional MRI is its ability to reduce partial volume averaging artifacts and create multiplanar reconstruction (MPRs) in any plane with any slice thickness from a single high-resolution isotropic acquisition. 3D MRI acquisitions are particularly useful for the evaluation of articular cartilage, which is prone to volume averaging artifacts, and for the assessment of longitudinally coursing structures such as peripheral nerves and tendons, which are better visualized with non-orthogonal MPRs. 3D MRI is also useful for surface and volumetric analysis of bone and cartilage for preoperative and longitudinal assessments. Current research is focused on decreasing acquisition times and automating segmentation through machine learning, thus overcoming some of the current limitations of 3D MRI and providing new applications for this technique.
Summary
3D MRI is widely used in MSK imaging today, and its use is likely to continue to increase in the future, with recent advancements focused on accelerated acquisition techniques and quantitative imaging.
The Emerging Role of 7 Tesla MRI in Musculoskeletal Imaging
Abstract
Purpose of Review
To describe the emergent role of ultra-high field (UHF) MR with respect to musculoskeletal MRI applications.
Recent Findings
With the recent US Federal Drug Administration (FDA) and European Union (EU) approval of ultra-high field (UHF) MRI below 8T for clinical use, and the availability of clinical 7T MRI systems, there is a rising interest in the potential clinical and research applications in musculoskeletal MRI.
Summary
With increases in field strength and SNR gains resulting in sharper and higher spatial resolution MRI images, there is increasing interest in UHF MRI. Although there are challenges and limitations in UHF, there are many new and unique musculoskeletal MR applications that UHF excels at such as morphological imaging, bone micro-architecture evaluation, biochemical imaging techniques such gagCEST, UTE/ZTE, T2 mapping, T2* mapping, T1ρ mapping, and multi-nuclear imaging and spectroscopy/imaging techniques with 23Na and 31P. The goal of this review is to highlight some of these recent findings in musculoskeletal MRI applications at UHF.
MR Imaging of Chondrogenic Tumors: Update on Select Imaging Challenges
Abstract
Purpose of Review
This review article discusses the updated World Health Classification of chondrogenic skeletal tumors and the role of conventional and advanced magnetic resonance (MR) imaging in the evaluation of chondrogenic skeletal lesions with emphasis on select diagnostic dilemmas.
Recent Findings
The majority of benign chondrogenic skeletal lesions have typical radiographic and MR features. Conventional MR imaging sequences can be helpful in the distinction of tumor-like lesions from chondrogenic tumors, and the evaluation of anatomic extent, particularly with regard to the detection of soft tissue masses associated with a chondrosarcoma (CS). Benign, atypical, and malignant chondrogenic lesions can have overlapping features on diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) mapping although dynamic contrast-enhanced (DCE) sequences can be helpful in the characterization of chondrogenic tumors as benign or malignant. Patients with multiple chondrogenic tumor conditions or syndromes are predisposed to developing CS and extra-skeletal malignancies, and as such, a small subset may benefit from imaging surveillance.
Summary
The majority of chondrogenic skeletal lesions can be characterized confidently on imaging. In the small subset of intermediate and malignant chondrogenic lesions with overlapping imaging and pathological features, a multidisciplinary approach should be used.
MRI of Acute Abdominal and Pelvic Non-obstetric Conditions in Pregnancy
Abstract
Purpose of Review
The evaluation of abdominal and pelvic pain in the pregnant patient presents unique challenges due to altered physiology and implications of radiation exposure on the fetus. In many instances, a radiologist must consider the potential risk of fetal injury from ionizing radiation and maintaining diagnostic quality imaging. This article will focus on the role of MR imaging and its applications in a variety of acute abdomen and pelvic non-obstetric conditions potentially affecting the pregnant patient.
Recent Findings
Non-contrast MR imaging is routinely employed in the presence of an initial equivocal ultrasound. However, MR is playing an increasingly more important role in the imaging of the pregnant patient, potentially surpassing the utility of conventional imaging techniques.
Summary
As radiologists become more comfortable interpretating abdominal and pelvic MRI, MR will play a bigger role in imaging the pregnant patient in the emergency room, in the years to come.
CT Imaging of Cardiac Trauma
Abstract
Cardiac injury can occur in the setting of blunt and penetrating trauma resulting in significantly adverse clinical outcomes. While the clinical presentation is variable and computed tomographic (CT) imaging is rarely performed to specifically evaluate for cardiac injury, the ability to recognize the findings of cardiac injury on CT examinations performed for thoracic trauma is essential to avoid misdiagnosis and direct potentially life-saving intervention. This article reviews the direct and indirect CT findings of cardiac injury.
A systematic review and meta-analysis of the prevalence and phenotype of adult-onset atopic dermatitis
Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Harrison H. Lee, Kevin R. Patel, Vivek Singam, Supriya Rastogi, Jonathan I. Silverberg
BackgroundPrevious studies found conflicting results about whether atopic dermatitis (AD) begins in adulthood.ObjectiveTo determine rates, predictors and phenotypical differences of adult-onset AD.MethodsA systematic review was performed of all published observational studies in MEDLINE, EMBASE, GREAT, LILACS, Cochrane Library, and Scopus that analyzed the age of AD onset beyond 10 years of age. Two reviewers performed study title/abstract review and data abstraction. Pooled meta-analysis of the proportion of adult-onset AD was performed using random-effects weighting (I2=99.3%).ResultsOverall, 25 studies met inclusion criteria. Seventeen studies reported age of AD-onset past 16 years and had sufficient data for meta-analysis. The pooled proportion (95% CI) of adult-onset AD was 26.1% (16.5-37.2%). Similar results were found in sensitivity analyses by diagnostic method for AD, study region, and gender. Phenotypical differences were observed across studies for adult vs. child onset AD, including higher rates of foot dermatitis and personal history of atopy, but lower rates of flexural lesions and other signs and symptoms.LimitationsCharacteristics of adult- vs. child-onset AD were not commonly reported.ConclusionsAD is not only a disease of childhood. One in 4 adults with AD report adult-onset disease. Adult-onset AD was associated with distinct clinical characteristics.
Folliculitis Decalvans: Effectiveness of Therapies and Prognostic Factors In A Multicenter Series of 60 Patients With Long-Term Follow-Up
Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): L. Miguel-Gómez, A.R. Rodrigues-Barata, A. Molina-Ruiz, A. Martorell-Calatayud, P. Fernández-Crehuet, R. Grimalt, D. Barco, S. Arias-Santiago, C. Serrano-Falcón, F.M. Camacho, D. Saceda-Corralo, P. Jaén-Olasolo, S. Vañó-Galván
REPLY to MS#JAAD-D-18-00380
Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Samir Arbache
Reply to: comment on “Liquid nitrogen cryotherapy for chronic recalcitrant interdigital candidiasis of toe-spaces – an uncontrolled pilot study”
Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Vijay Zawar, Manoj Pawar, R Raghunatha Reddy, Antonio Chuh
About melanocyte activation in idiopathic guttate hypomelanosis by 5-fluorouracil tattooing
Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Carlos Gustavo Wambier
Influence of age and marital status on stage at diagnosis and survival of patients with Merkel cell carcinoma: a SEER based cohort study
Publication date: Available online 2 June 2018
Source:Journal of the American Academy of Dermatology
Author(s): Michael A. Liu, Jannett Nguyen, Jane A. Driver
Bayesian inference for the genetic control of water deficit tolerance in spring wheat by stochastic search variable selection
Abstract
Drought is the main abiotic stress seriously influencing wheat production. Information about the inheritance of drought tolerance is necessary to determine the most appropriate strategy to develop tolerant cultivars and populations. In this study, generation means analysis to identify the genetic effects controlling grain yield inheritance in water deficit and normal conditions was considered as a model selection problem in a Bayesian framework. Stochastic search variable selection (SSVS) was applied to identify the most important genetic effects and the best fitted models using different generations obtained from two crosses applying two water regimes in two growing seasons. The SSVS is used to evaluate the effect of each variable on the dependent variable via posterior variable inclusion probabilities. The model with the highest posterior probability is selected as the best model. In this study, the grain yield was controlled by the main effects (additive and non-additive effects) and epistatic. The results demonstrate that breeding methods such as recurrent selection and subsequent pedigree method and hybrid production can be useful to improve grain yield.
Applicability of radon emanometry in lithologically discontinuous sites contaminated by organic chemicals
Abstract
The applicability of radon (222Rn) measurements to delineate non-aqueous phase liquids (NAPL) contamination in subsoil is discussed at a site with lithological discontinuities through a blind test. Three alpha spectroscopy monitors were used to measure radon in soil air in a 25,000-m2 area, following a regular sampling design with a 20-m2 grid. Repeatability and reproducibility of the results were assessed by means of duplicate measurements in six sampling positions. Furthermore, three points not affected by oil spills were sampled to estimate radon background concentration in soil air. Data histograms, Q-Q plots, variograms, and cluster analysis allowed to recognize two data populations, associated with the possible path of a fault and a lithological discontinuity. Even though the concentration of radon in soil air was dominated by this discontinuity, the characterization of the background emanation in each lithological unit allowed to distinguish areas potentially affected by NAPL, thus justifying the application of radon emanometry as a screening technique for the delineation of NAPL plumes in sites with lithological discontinuities.
An automated liver tumour segmentation from abdominal CT scans for hepatic surgical planning
Abstract
Purpose
Segmentation of liver tumours is an important part of the 3D visualisation of the liver anatomy for surgical planning. The spatial relationship between tumours and other structures inside the liver forms the basis of preoperative surgical risk assessment. However, the automatic segmentation of liver tumours from abdominal CT scans is riddled with challenges. Tumours located at the border of the liver impose a big challenge as the surrounding tissues could have similar intensities.
Methods
In this work, we introduce a fully automated liver tumour segmentation approach in contrast-enhanced CT datasets. The method is a multi-stage technique which starts with contrast enhancement of the tumours using anisotropic filtering, followed by adaptive thresholding to extract the initial mask of the tumours from an identified liver region of interest. Localised level set-based active contours are used to extend the mask to the tumour boundaries.
Results
The proposed method is validated on the IRCAD database with pathologies that offer highly variable and complex liver tumours. The results are compared quantitatively to the ground truth, which is delineated by experts. We achieved an average dice similarity coefficient of 75% over all patients with liver tumours in the database with overall absolute relative volume difference of 11%. This is comparable to other recent works, which include semiautomated methods, although they were validated on different datasets.
Conclusions
The proposed approach aims to segment tumours inside the liver envelope automatically with a level of accuracy adequate for its use as a tool for surgical planning using abdominal CT images. The approach will be validated on larger datasets in the future.
Main controlling factors and forecasting models of lead accumulation in earthworms based on low-level lead-contaminated soils
Abstract
To explore the main controlling factors in soil and build a predictive model between the lead concentrations in earthworms (Pbearthworm) and the soil physicochemical parameters, 13 soils with low level of lead contamination were used to conduct toxicity experiments using earthworms. The results indicated that a relatively high bioaccumulation factor appeared in the soils with low pH values. The lead concentrations between earthworms and soils after log transformation had a significantly positive correlation (R2 = 0.46, P < 0.0001, n = 39). Stepwise multiple linear regression analysis derived a fitting empirical model between Pbearthworm and the soil physicochemical properties: log(Pbearthworm) = 0.96log(Pbsoil) − 0.74log(OC) − 0.22pH + 0.95, (R2 = 0.66, n = 39). Furthermore, path analysis confirmed that the Pb concentrations in the soil (Pbsoil), soil pH, and soil organic carbon (OC) were the primary controlling factors of Pbearthworm with high pathway parameters (0.71, − 0.51, and − 0.49, respectively). The predictive model based on Pbearthworm in a nationwide range of soils with low-level lead contamination could provide a reference for the establishment of safety thresholds in Pb-contaminated soils from the perspective of soil-animal systems.
Association of phthalate exposure with anthropometric indices and blood pressure in first-grade children
Abstract
We aimed to assess the relationship of urine phthalate metabolite concentrations with anthropometric indices, and blood pressure in first-grade children. We detected 11 phthalate metabolites in urine and estimated anthropometric indices, including skinfold measurements, waist circumference (WC), and body mass index (BMI) in 276 children aged 6–8 years. Multivariate linear regression models were used to assess the associations between urinary phthalate metabolite levels, and anthropometric and blood pressure indices in a gender-specific manner. In boys, a 1-ng/mL increase in monobenzyl phthalate (MBzP) concentration was associated with a 0.027-cm decrease in the skinfold measurement (95% confidence interval [CI], − 0.053 to 0.001), whereas a 1-ng/mL increase in mono-ethyl-phthalate (MEP) concentration was associated with a 0.016-mm Hg decrease in systolic blood pressure (95% CI, − 0.031 to 0.001). MBzP, mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), and MEOHP concentrations were also inversely associated with WC. However, in girls, MEP concentrations were positively associated with chest measurements, but were inversely associated with WC. A 1-ng/mL increase in monomethyl phthalate concentrations was associated with a 0.039-cm increase in skinfold measurements (95% CI, 0.002 to 0.076), whereas a 1-ng/mL increase in MECPP concentrations was associated with a 0.050 cm decrease in skinfold measurements (95% CI, − 0.095 to − 0.005). In this exploratory, cross-sectional analysis, we identified various interesting associations between different phthalate metabolite levels and anthropometric indices, which suggest that some of phthalate metabolite should be considered in addition to the prevalence rates of overweight and obesity.
Combined effects of coagulation and adsorption on ultrafiltration membrane fouling control and subsequent disinfection in drinking water treatment
Abstract
This study investigated the combined effects of coagulation and powdered activated carbon (PAC) adsorption on ultrafiltration (UF) membrane fouling control and subsequent disinfection efficiency through filtration performance, dissolved organic carbon (DOC) removal, fluorescence excitation-emission matrix (EEM) spectroscopy, and disinfectant curve. The fouling behavior of UF membrane was comprehensively analyzed especially in terms of pollutant removal and fouling reversibility to understand the mechanism of fouling accumulation and disinfectant dose reduction. Pre-coagulation with or without adsorption both achieved remarkable effect of fouling mitigation and disinfection dose reduction. The two pretreatments were effective in total fouling control and pre-coagulation combined with PAC adsorption even decreased hydraulically irreversible fouling notably. Besides, pre-coagulation decreased residual disinfectant decline due to the removal of hydrophobic components of natural organic matters (NOM). Pre-coagulation combined with adsorption had a synergistic effect on further disinfectant decline rate reduction and decreased total disinfectant consumption due to additional removal of hydrophilic NOM by PAC adsorption. The disinfectant demand was further reduced after membrane. These results show that membrane fouling and disinfectant dose can be reduced in UF coupled with pretreatment, which could lead to the avoidance of excessive operation cost disinfectant dose for drinking water supply.
Evaluating the effects of phytoremediation with biochar additions on soil nitrogen mineralization enzymes and fungi
Abstract
Phytoremediation with biochar addition might alleviate pollutant toxicity to soil microorganism. It is uncertain to what extent biochar addition rate could affect activities of enzymes related to soil nitrogen (N) mineralization and alter fungal community under the phytoremediation. This study aimed to reveal the effects of Medicago sativa L. (alfalfa) phytoremediation, alone or with biochar additions, on soil protease and chitinase and fungal community and link the responses of microbial parameters with biochar addition rates. The alfalfa phytoremediation enhanced soil protease activities, and relative to the phytoremediation alone, biochar additions had inconsistent impacts on the corresponding functional gene abundances. Compared with the blank control, alfalfa phytoremediation, alone or with biochar additions, increased fungal biomass and community richness estimators. Moreover, relative to the phytoremediation alone, the relative abundances of phylum Zygomycota were also increased by biochar additions. The whole soil fungal community was not significantly changed by the alfalfa phytoremediation alone, but was indeed changed by alfalfa phytoremediation with 3.0% (w/w) or 6.0% biochar addition. This study suggested that alfalfa phytoremediation could enhance N mineralization enzyme activities and that biochar addition rates affected the responses of fungal community to the alfalfa phytoremediation.
Effects of perfluorooctane sulfonate on genes controlling hepatic fatty acid metabolism in livers of chicken embryos
Abstract
Per- and polyfluoroalkyl substances (PFAS) are synthetic surfactants with a wide variety of applications; however, due to their stability, they are particularly resistant to degradation and, as such, are classed as persistent organic pollutants. Perfluorooctane sulfonate (PFOS) is one such PFAS that is still detectable in a range of different environmental settings, despite its use now being regulated in numerous countries. Elevated levels of PFOS have been detected in various avian species, and the impact of this on avian health is of interest when determining acceptable levels of PFOS in the environment. Due to its similarities to naturally occurring fatty acids, PFOS has potential to disrupt a range of biological pathways, particularly those associated with lipid metabolism, and this has been shown in various species. In this study, we have investigated how in ovo exposure to environmentally relevant levels of PFOS affects expression of genes involved in lipid metabolism of developing chicken embryos. We have found a broad suppression of transcription of genes involved in fatty acid oxidation and PPAR-mediated transcription with more significant effects apparent at lower doses of PFOS. These results highlight the need for more research investigating the biological impacts of low levels of PFAS to properly inform environmental policy governing their regulation.
Functionalized three-dimensional graphene sponges for highly efficient crude and diesel oil adsorption
Abstract
Modified Hummer's method has been used in this study to synthesize graphene oxide (GO) solution that was utilized for the fabrication of three-dimensional (3D) graphene sponges and their subsequent functionalization through a low-cost and facile vapor-based surface enhancement approach. The functionalized 3D-graphene sponge is an excellent absorbent, which can remove more than 3300 wt.% of crude oil (calculated with respect to the original sorbent mass). The functionalization of the obtained graphene sponges with trichloro (1H,1H,2H,2H-perfluorooctyl)silane enhanced their wettability properties due to the super-hydrophobic nature of the resulting materials characterized by the contact angles in water greater than 150°. Furthermore, their elastic compression modulus (estimated by conducting a series of compression tests) was about 22.3 kPa. The equilibrium modeling of the oil removal process, which was performed by plotting Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherms, confirmed the properties of the fabricated 3D graphene sponges as exceptional absorbents for crude and diesel oil, which could be attributed to the oleophilic nature of graphene. Moreover, the obtained 3D graphene sponges could be regenerated via heat treatment, which was conducted to release the adsorbed species. After five adsorption-desorption cycles, the sorption capacity of the produced 3D graphene sponges towards crude oil reached 95% of the initial value.
Sequential extraction of chromium, molybdenum, and vanadium in basic oxygen furnace slags
Abstract
Basic oxygen furnace slags (BOS) are by-products of basic oxygen steel production. Whereas the solubility of some elements from these slags has been well investigated, information about the mineralogy and related leaching, i.e., availability of the environmentally relevant elements chromium (Cr), molybdenum (Mo), and vanadium (V), is still lacking. The aim of this study was to investigate these issues with a modified, four-fraction-based, sequential extraction procedure (F1–F4), combined with X-ray diffraction, of two BOS. Extractants with increasing strength were used (F1 demineralized water, F2 CH3COOH + HCl, F3 Na2EDTA + NH2OH·HCl, and F4 HF + HNO3 + H2O2), and after each fraction, X-ray diffraction was performed. The recovery of Cr was moderate (66.5%) for one BOS, but significantly better (100.2%) for the other one. High recoveries were achieved for the other elements (Mo, 100.8–107.9% and V, 112.6–87.0%), indicating that the sequential extraction procedure was reliable when adapted to BOS. The results showed that Cr and Mo primarily occurred in F4, representing rather immobile elements under natural conditions, which were strongly bound into/onto Fe minerals (srebrodolskite, magnetite, hematite, or wustite). In contrast, V was more mobile with proportional higher findings in F2 and F3, and the X-ray diffraction results reveal that V was not solely bound into Ca minerals (larnite, hatrurite, kirschsteinite, and calcite), but also bound to Fe minerals. The results indicated that the total amount of recovery was a poor indicator of the availability of elements and did not correspond to the leaching of elements from BOS.
Julius Caesar and the numbers
Abstract
This article offers an interpretation of a controversial aspect of Frege's The Foundations of Arithmetic, the so-called Julius Caesar problem. Frege raises the Caesar problem against proposed purely logical definitions for '0', 'successor', and 'number', and also against a proposed definition for 'direction' as applied to lines in geometry. Dummett and other interpreters have seen in Frege's criticism a demanding requirement on such definitions, often put by saying that such definitions must provide a criterion of identity of a certain kind (for numbers or for linear directions). These interpretations are criticized and an alternative interpretation is defended. The Caesar problem is that the proposed definitions fail to well-define 'number' and 'direction'. That is, the proposed definitions, even when taken together with the extra-definitional facts (such as that Caesar is not a number and that England is not a direction), fail to fix unique semantic extensions for 'number' and 'direction', and thereby fail to fix unique truth-values for sentences like 'Caesar is a number' and 'England is a direction'. A minor modification of the criticized definitions well-defines '0', 'successor' and 'number', thereby avoiding the Caesar problem as Frege understands it, but without providing any criterion of number identity in the usual sense.
Nódulos múltiples hipopigmentados adquiridos en la cara anterior del tórax
Publication date: Available online 1 June 2018
Source:Actas Dermo-Sifiliográficas
Author(s): M. Quintana-Codina, G. Melé-Ninot, C. Santonja
Psoriasis ungueal tratada con certolizumab pegol en pacientes con artritis psoriásica: conclusión preliminar
Publication date: Available online 1 June 2018
Source:Actas Dermo-Sifiliográficas
Author(s): M. Mazzeo, A. Dattola, M.V. Cannizzaro, L. Bianchi
Using natural clinoptilolite zeolite as an amendment in vermicomposting of food waste
Abstract
The effect of adding different proportions of natural clinoptilolite zeolite (5 and 10%) to food waste vermicomposting was investigated by assessing the physicochemical characteristics, worms' growth, and maturation time of finished vermicompost in comparison with the vermicompost prepared with no amendment (control). Vermicomposting was performed in 18 plastic containers for 70 days. The experimental results showed that the carbon-to-nitrogen (C/N) ratios were 15.85, 10.75, and 8.94 for 5 and 10% zeolite concentration and control after 70 days, respectively. The addition of zeolite could facilitate organic matter degradation and increase the total nitrogen content by adsorption of ammonium ions. Increasing the proportion of zeolite from 0% (control) to 10% decreased the ammonia escape by 25% in the final vermicompost. The natural zeolite significantly reduced the electrical conductivity (EC). At the end of the process, salinity uptake efficiency was 39.23% for 5% zeolite treatment and 45.23% for 10% zeolite treatment. The pH values at 5 and 10% zeolite-amended treatments were 7.31 and 7.57, respectively, in comparison to 7.10 in the control. The maturation time at the end of vermicomposting decreased with increasing zeolite concentration. The vermicompost containing 5 and 10% zeolite matured in 49 and 42 days, respectively, in comparison to 56 days for the control. With the use of an initial ten immature Eisenia fetida worms, the number of mature worms in the 10% zeolite treatment was 26 more than that in the 5% zeolite treatment (21 worms) and 9 more than that in the control treatment (17 worms). Significantly, natural zeolite showed a beneficial effect on the characteristics of the end-product when used in the vermicomposting of food waste.
Impact assessment of leaf pigments in selected landscape plants exposed to roadside dust
Abstract
Continuous addition of undesired effluents to the environment affects foliar surface of leaf, changes their morphology, stomata, photosynthetic pigments, and biochemical constituents which result in massive damage due to persistent nature of the pollutant. In persistent hostile environment, plants fail to grow and develop, and the effects are often extensive. In current study, landscape plants were exposed to different levels of road dust to analyze the effect on various photosynthetic pigments. Dry roadside sediments were collected through a vacuum pump and passed through filters to get fine particles less than 100 μm and sprinkled on Euphorbia milii (EM), Gardenia jasminoides (GJ), and Hibiscus rosa-sinensis (HRs) by using a hand pump, twice daily at T1 (control), T2, T3, and T4 (0, 2, 4, and 6 g/plant, respectively) for a period of 3 months in green house. Road sediment significantly reduces leaf pigments in landscape plants population and the effects were more severe in high level of dust deposition. Individual response of EM, GJ, and HRs to different levels of road dust was variable; however, road sediment significantly reduces leaf pigments at high dose of roadside dust deposition. EM plants exposed to 2 g/plant roadside dust showed higher chlorophyll-a, chlorophyll-b, total chlorophyll, chlorophyllide-b, and polar carotenoid contents as compared to GJ and HRs. Leaf chlorophyll-a, chlorophyll-b, total chlorophyll, carotenoid, and polar carotenoid contents of EM were higher than GJ and HRs in T3 and T4 treatments. However HRs showed significantly higher protochlorophyllide, chlorophyllide-a, and pheophytin-b contents of leaf in T4 group. EM was found as tolerant landscape plant followed by HRs. GJ was most vulnerable to road dust stress. Present study concludes that the entire biosynthesis of leaf pigments is in chain and interlinked together where effect of road dust on one pigment influences other pigments and their derivatives. Salient features of the present study provide useful evidence to estimate roadside dust as a major risk factor for plant pigments, and plants in green belt along roadside suffer retarded growth and fail to establish and develop.
Design and experimental investigations on six-stroke SI engine using acetylene with water injection
Abstract
In the present study, a four-stroke cycle gasoline engine is redesigned and converted into a six-stroke cycle engine and experimental study has been conducted using gasoline and acetylene as fuel with water injection at the end of the recompression stroke. Acetylene has been used as an alternative fuel along with gasoline and performance of the six-stroke spark ignition (SI) engine with these two fuels has been studied separately and compared. Brake power and thermal efficiency are found to be 5.18 and 1.55% higher with acetylene as compared to gasoline in the six-stroke engine. However, thermal efficiency is found to be 45% higher with acetylene in the six-stroke engine as compared to four-stroke SI engine. The CO and HC emissions were found to be reduced by 13.33 and 0.67% respectively with acetylene as compared to gasoline due to better combustion of acetylene. The NOx emission was reduced by 5.65% with acetylene due to lower peak temperature by water injection. The experimental results showed better engine performance and emissions with acetylene as fuel in the six-stroke engine.
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A Case of Diprosopus Tetraophthalmos: Ocular Findings and Surgical Treatment of Exposure KeratopathyDiprosopus is a rare variation of conjoined twinning. In this report, ophthalmic findings in an infant with diprosopus tetraophthalmos are p...
