Changes of biotoxicity in food waste fermentation wastewater treated by a membrane bioreactor system

Abstract

The biotoxicity of industrial effluents has attracted much concern in the wastewater treatment process. This research performed the biological treatment of the wastewater generated from food waste fermentation by anaerobic/anaerobic/anoxic/aerobic-membrane bioreactor (A³-MBR) system aiming at the meet of discharge standards and elimination of ecological risks to aquatic environment. The results showed that the A³-MBR could effectively remove pollutants such as COD, TN, ammonia, and TP in the wastewater. The study of biotoxicity revealed that the acute toxicity was mainly contained in the polar and mid-polar fractions of the wastewater, and the remained acute toxicity was less than 0.6 TU, much lower than the secondary effluent of domestic wastewater treatment plant. The genotoxicity was found abundantly in the polar fractions and less in mid-polar fractions, and a relatively low genotoxicity (0.086 μg 4-NQO/L) was obtained in the final effluent of the treatment system. The fulvic acid-like compounds and humic acid-like compounds were the main cause of the acute toxicity, while the aromatic proteins and soluble microbial by-products mainly resulted in the genotoxicity in the wastewater.

Impact of selected drugs and their binary mixtures on the germination of Sorghum bicolor (sorgo) seeds

Abstract

The aim of this study was to assess the toxicological potential of binary drug mixtures and individual drugs under different pH conditions with different inorganic ion additions on the germination of Sorghum bicolor (sorgo) seeds. To assess whether the given drug mixtures were more phytotoxic than the individual compounds, concentration addition (CA) and independent action (IA) approaches were applied to estimate the predicted phytotoxicity values, followed by calculations of the MDR (model deviation factor) to determine the deviation from the predicted values. Binary mixtures of chloramphenicol with ketoprofen, diclofenac sodium, and oxytetracycline hydrochloride proved to be synergistic. The pH changes had the largest impact on the phytotoxicity of the diclofenac sodium and ketoprofen solutions, elevating their toxicity toward S. bicolor, and the co-presence of inorganic ions was shown to have an impact on ketoprofen, chloramphenicol, and oxytetracycline hydrochloride. Most of the interactions between sorgo plants and pharmaceuticals with added ions were antagonistic in nature, particularly those calculated using the IA model, with a few cases (one case for ketoprofen and chloramphenicol, two cases for oxytetracycline hydrochloride, and four cases for diclofenac sodium) of overestimation.

Facile synthesis of highly porous “carbon sponge” with adsorption and co-adsorption behavior of lead ions and atrazine

Abstract

The rapid industrialization and modern agriculture, increasing emission of heavy metals, and abusing application of pesticide have changed biochemical features of the soil system and water system. Additionally, heavy metals and pesticide compounds may occur together in environments, giving rise to more serious damage to the environment because of their combined toxicity and carcinogenic properties. Therefore, there is a growing need for the development of low-cost adsorbents for their removal. Porous carbon materials have been considered as highly effective materials for pollutant ion control. In this thesis, a novel porous "carbon sponge" is produced using sucrose (S-PCS) with gas-producing molten salt KHCO₃ as the activator at different pyrolysis temperatures under a limited-oxygen condition. Results from these characterizations have indicated that the as-prepared carbon sponges share high surface area (up to 457.6434 m² g⁻¹) and abundant oxygen-containing functional groups existed on the surface. The essential factors of contact time, initial concentrations, and cyclic availability on adsorption of lead ions and atrazine onto the as-prepared porous samples are also discussed. The typical kinetic and thermodynamic models are carried out to interpret the adsorption behaviors of lead ions and atrazine. The interactive effects and mechanism of lead ions and atrazine adsorption onto S-PCS samples are examined by simultaneous adsorption and preloading adsorption procedures. Combined with the economic and environmental merits of the raw materials, the porous carbon sponges of sucrose by KHCO₃ activated are promising materials for potential practical applications.

Graphical abstract

The schematic diagram on the preparation of porous carbon sponse from sucrose.

Ionizing radiation exposure: hazards, prevention, and biomarker screening

Abstract

Radiation is a form of energy derived from a source that is propagated through material in space. It consists of ionizing radiation or nonionizing radiation. Ionizing radiation is a feature of the environment and an important tool in medical treatment, but it can cause serious damage to organisms. A number of protective measures and standards of protection have been proposed to protect against radiation. There is also a need for biomarkers to rapidly assess individual doses of radiation, which can not only estimate the dose of radiation but also determine its effects on health. Proteomics, genomics, metabolomics, and lipidomics have been widely used in the search for such biomarkers. These topics are discussed in depth in this review.

Concentration-dependent responses of soil bacterial, fungal and nitrifying communities to silver nano and micron particles

Abstract

The growing use of silver nanoparticles (AgNPs) is likely to result in increased environmental contamination. Although AgNPs have been reported to affect microbial communities in a range of ecosystems, there is still a lack of information concerning the effect of low concentrations of AgNPs on soil microbial community structures and functional groups involved in biogeochemical cycling. In this study, the concentration-dependent effects of AgNPs and silver micron particles (AgMPs) on bacterial and fungal community structures in an agricultural pastureland soil were examined in a microcosm-based experiment using enzyme analysis, molecular fingerprinting, qPCR and amplicon sequencing. Soil enzyme processes were impacted by Ag contamination, with soil dehydrogenase activity reduced by 1 mg kg⁻¹ of AgNPs and AgMPs. Soil urease activity was less susceptible, but was inhibited by ≥ 10 mg kg⁻¹ AgNPs. The significant (P ≤ 0.001) decrease in copy numbers of the amoA gene by 10 mg kg⁻¹ AgNPs indicated that archaea ammonia oxidisers may be more sensitive to AgNP contamination than bacteria. Amplicon sequencing revealed the bacterial phyla Acidobacteria and Verrucomicrobia to be highly sensitive to AgNP contamination. A broad reduction in the relative abundance of Acidobacterial genera was observed, with the exception of the genus Geothrix which increased in response to AgNP and AgMP amendment. Broad tolerance to Ag was observed among the Bacteriodetes, with higher relative abundance of most genera observed in the presence of AgNPs and AgMPs. The proteobacterial genus Dyella was highly tolerant to AgNPs and AgMPs and relative abundance of this genus increased with Ag concentration. Soil fungal community structure responded to both AgNPs and AgMPs, but the nanoparticle had an impact at a lower concentration. This study demonstrates that pastureland soil microbial communities are highly sensitive to AgNP amendment and key functional processes may be disrupted by relatively low levels of contamination.

Laparoscopic training using a quantitative assessment and instructional system

Abstract

Purpose

Laparoscopic surgery requires complex surgical skills; hence, surgeons require regular training to improve their surgical techniques. The quantitative assessment of a surgeon's skills and the provision of feedback are important processes for conducting effective training. The aim of this study was to develop an inexpensive training system that provides automatic technique evaluation and feedback.

Methods

We detected the instrument using image processing of commercial web camera images and calculated the motion analysis parameters (MAPs) of the instrument to quantify performance features. Upon receiving the results, we developed a method of evaluating the surgeon's skill level. The feedback system was developed using MAPs-based radar charts and scores for determining the skill level. These methods were evaluated using the videos of 38 surgeons performing a suturing task.

Results

There were significant differences in MAPs among surgeons; therefore, MAPs can be effectively used to quantify a surgeon's performance features. The results of skill evaluation and feedback differed greatly between skilled and unskilled surgeons, and it was possible to indicate points of improvement for the procedure performed in this study. Furthermore, the results obtained for certain novice surgeons were similar to those obtained for skilled surgeons.

Conclusion

This system can be used to assess the skill level of surgeons, independent of the years of experience, and provide an understanding of the individual's current surgical skill level effectively. We conclude that our system is useful as an inexpensive laparoscopic training system that might aid in skill improvement.

Exploiting the potential of unlabeled endoscopic video data with self-supervised learning

Abstract

Purpose

Surgical data science is a new research field that aims to observe all aspects of the patient treatment process in order to provide the right assistance at the right time. Due to the breakthrough successes of deep learning-based solutions for automatic image annotation, the availability of reference annotations for algorithm training is becoming a major bottleneck in the field. The purpose of this paper was to investigate the concept of self-supervised learning to address this issue.

Methods

Our approach is guided by the hypothesis that unlabeled video data can be used to learn a representation of the target domain that boosts the performance of state-of-the-art machine learning algorithms when used for pre-training. Core of the method is an auxiliary task based on raw endoscopic video data of the target domain that is used to initialize the convolutional neural network (CNN) for the target task. In this paper, we propose the re-colorization of medical images with a conditional generative adversarial network (cGAN)-based architecture as auxiliary task. A variant of the method involves a second pre-training step based on labeled data for the target task from a related domain. We validate both variants using medical instrument segmentation as target task.

Results

The proposed approach can be used to radically reduce the manual annotation effort involved in training CNNs. Compared to the baseline approach of generating annotated data from scratch, our method decreases exploratively the number of labeled images by up to 75% without sacrificing performance. Our method also outperforms alternative methods for CNN pre-training, such as pre-training on publicly available non-medical (COCO) or medical data (MICCAI EndoVis2017 challenge) using the target task (in this instance: segmentation).

Conclusion

As it makes efficient use of available (non-)public and (un-)labeled data, the approach has the potential to become a valuable tool for CNN (pre-)training.

Effective deep learning training for single-image super-resolution in endomicroscopy exploiting video-registration-based reconstruction

Abstract

Purpose

Probe-based confocal laser endomicroscopy (pCLE) is a recent imaging modality that allows performing in vivo optical biopsies. The design of pCLE hardware, and its reliance on an optical fibre bundle, fundamentally limits the image quality with a few tens of thousands fibres, each acting as the equivalent of a single-pixel detector, assembled into a single fibre bundle. Video registration techniques can be used to estimate high-resolution (HR) images by exploiting the temporal information contained in a sequence of low-resolution (LR) images. However, the alignment of LR frames, required for the fusion, is computationally demanding and prone to artefacts.

Methods

In this work, we propose a novel synthetic data generation approach to train exemplar-based Deep Neural Networks (DNNs). HR pCLE images with enhanced quality are recovered by the models trained on pairs of estimated HR images (generated by the video registration algorithm) and realistic synthetic LR images. Performance of three different state-of-the-art DNNs techniques were analysed on a Smart Atlas database of 8806 images from 238 pCLE video sequences. The results were validated through an extensive image quality assessment that takes into account different quality scores, including a Mean Opinion Score (MOS).

Results

Results indicate that the proposed solution produces an effective improvement in the quality of the obtained reconstructed image.

Conclusion

The proposed training strategy and associated DNNs allows us to perform convincing super-resolution of pCLE images.

Knowledge transfer for surgical activity prediction

Abstract

Purpose

Lack of annotated training data hinders automatic recognition and prediction of surgical activities necessary for situation-aware operating rooms. We propose using knowledge transfer to compensate for data deficit and improve prediction.

Methods

We used two approaches to extract and transfer surgical process knowledge. First, we encoded semantic information about surgical terms using word embedding. Secondly, we passed knowledge between different clinical datasets of neurosurgical procedures using transfer learning.

Results

The combination of two methods provided 22% improvement of activity prediction. We also made several pertinent observations about surgical practices based on the results of the performed transfer.

Conclusion

Word embedding boosts learning process. Transfer learning was shown to be more effective than a simple combination of data, especially for less similar procedures.

Cadmium bioaccumulation and antioxidant enzyme activity in hepatopancreas, kidney, and stomach of invasive apple snail Pomacea canaliculata

Abstract

The acute toxicity of Cd was tested, and metal bioaccumulation in tissue was determined for the alien invasive species Pomacea canaliculata and its native competitor Sinotaia quadrata under experimental conditions. The invasive species was more tolerant to Cd toxicity than native species, for which the LC₅₀ values were 4.26, 2.24, and 1.98 mg/L at exposure times of 48, 72, and 96 h, respectively, approximately three times higher than those of the native snails. The viscera accumulated the highest Cd concentration, followed by the foot and shell in both species. Metal concentrations in the above three tissues of P. canaliculata were much higher than those of S. quadrata, irrespective of Cd dose and exposure time. For P. canaliculata, the highest concentration of metal was further observed in the hepatopancreas (0.64–3.98 mg/g) followed by the kidney (0.067–3.78 mg/g), with lowest levels in the stomach (0.062–1.53 mg/g). Among the five antioxidant enzymes, the most responsive enzymes were CAT, ALP, and GST in the hepatopancreas; CAT, POD, and GST in the kidney; and POD in the stomach of exposed animals. These results, demonstrating a high Cd tolerance, may partly explain the ability of P. canaliculata to displace S. quadrata in Cd-contaminated habitat. The Cd was accumulated mainly in the hepatopancreas and kidney of invasive species, which changed the activity of antioxidant enzymes allowing the animals to cope with the toxicity.

Graphical abstract

Cadmium bioaccumulation and antioxidant enzyme activity in the invasive Pomacea canaliculata.

Source characterization and risk of exposure to atmospheric polychlorinated biphenyls (PCBs) in Ghana

Abstract

With recent evidence that persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) are emerging in environmental media in some developing countries that otherwise have sparing production and usage history, it has become important to identify such contemporary source factors of PCBs and the risks this may pose, in line with the global consensus on POP management and elimination. The present study investigated contaminations from atmospheric PCBs in Ghana, deciphered source factors, and accessed risk of exposure to dioxin-like PCBs (DL-PCBs). Atmospheric PCBs were monitored by deployment of PUF-disk passive air samplers (PAS) at several sites across Ghana for 56 days. Atmospheric ∑₁₉₀PCB concentration in Ghana ranged from 0.28 ng/m³ in Kumasi to 4.64 ng/m³ at Agbogbloshie, a suburb in Accra noted for informal electronic waste (e-waste) recycling activities. As high as 11.10 ng/m³ of PCB concentration was measured in plumes from uncontrolled open burning of e-wastes at Agbogbloshie. Applying statistical source characterization tools, it emerged that e-wastes were a major contributor to the environmental burden of atmospheric PCBs in Ghana. The risk of DL-PCB toxicity via inhalation in the Agbogbloshie area was 4.2 pg TEQ/day, within similar order of magnitude of an estimated risk of 3.85 pg TEQ/day faced by e-waste workers working averagely for 8 h per day. It is suggested that elimination of e-waste sites would help to significantly reduce PCB-related toxicity issues in Ghana.

Graphical abstract

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Urban particulate matter in air pollution penetrates into the barrier-disrupted skin and produces ROS-dependent cutaneous inflammatory response in vivo

Particulate matters (PMs) are mixtures of particles suspended in the air. Their sources include factories, power plants, refuse incinerators, automobile, construction activities, fires and natural windblown dust [1]. Major components of PM are metals, organic compounds, materials of biologic origin, ions, and particle carbon core [2]. It also contains gases that are adsorbed onto the particles. PMs can be classified according to particulate size as PM0.1 (ultrafine particles, ≤ 0.1 μm), PM2.5 (fine particles, ≤ 2.5 μm), and PM10 (≤ 10 μm).

A novel, topical, nonsteroidal, TRPV1 antagonist, PAC-14028 cream improves skin barrier function and exerts anti-inflammatory action through modulating epidermal differentiation markers and suppressing Th2 cytokines in atopic dermatitis

Atopic dermatitis (AD), also known as atopic eczema, is the most common inflammatory skin disease characterized by chronic and relapsing episodes of intense pruritus, an impaired epidermal barrier and eczematous lesions [1–3]. AD occurs more frequently in younger individuals; in the developing countries, prevalence ranges from 15% to 30% in children and 2% to 10% in adults [1,4]. Most of the patients develop AD in early childhood but late-onset AD can occur at all ages. The course is heterogeneous and unpredictable as some patients develop persisting or chronic relapsing AD, whereas others lose nearly all symptoms until adolescence [5,6].

Ecological Expansion and Extinction in the Late Ediacaran: Weighing the Evidence for Environmental and Biotic Drivers

Abstract

The Ediacara Biota, Earth's earliest communities of complex, macroscopic, multicellular organisms, appeared during the late Ediacaran Period, just prior to the Cambrian Explosion. Ediacara fossil assemblages consist of exceptionally preserved soft-bodied forms of enigmatic morphology and affinity which nonetheless represent a critical stepping-stone in the evolution of complex animal ecosystems. The Ediacara Biota has historically been divided into three successive Assemblages—the Avalon, the White Sea and the Nama. Although the oldest (Avalon) Assemblage documents the initial appearance of several groups of Ediacara taxa, the two younger (White Sea and Nama) Assemblages record a particularly striking suite of ecological innovations, including the appearance of diverse Ediacara body plans—in tandem with the rise of bilaterian animals—as well as the emergence of novel ecological strategies such as movement, sexual reproduction, biomineralization and the development of dense, heterogeneous benthic communities. Many of these ecological innovations appear to be linked to adaptations to heterogeneous substrates and shallow and energetic marine settings. In spite of these innovations, the majority of Ediacara taxa disappear by the end of the Ediacaran, with interpretations for this disappearance historically ranging from the closing of preservational windows to environmentally or biotically mediated extinction. However, in spite of the unresolved affinity and eventual extinction of individual Ediacara taxa, these distinctive ecological strategies persist across the Ediacaran-Cambrian boundary and are characteristic of younger animal-dominated communities of the Phanerozoic. The late Ediacaran emergence of these strategies may, therefore, have facilitated subsequent radiations of the Cambrian. In this light, the Ediacaran and Cambrian Periods, although traditionally envisioned as separate worlds, are likely to have been part of an ecological and evolutionary continuum.

Neural Crest Transplantation Reveals Key Roles in the Evolution of Cavefish Development

Abstract

Evolutionary changes in Astyanax mexicanus cavefish with respect to conspecific surface fish, including the regression of eyes, loss of pigmentation, and modification of the cranial skeleton, involve derivatives of the neural crest. However, the role of neural crest cells in cavefish evolution and development is poorly understood. One of the reasons is that experimental methods for neural crest analysis are not well developed in the Astyanax system. Here we describe neural crest transplantation between Astyanax surface fish and cavefish embryos. We found differences in the migration of cranial neural crest cells transplanted from the surface fish anterior hindbrain to the same region of surface fish or cavefish hosts. Cranial neural crest cells migrated extensively throughout the head, and to a lesser extent the trunk, in surface fish hosts but their migration was mostly restricted to the anterior and dorsal head regions in cavefish hosts. Cranial neural crest cells derived from the surface fish transplants invaded the degenerating eyes of cavefish hosts, resulting in increased eye size and suggesting that cavefish neural crest cells are defective in forming optic derivatives. We found that melanophores were formed in albino cavefish from grafts of surface fish trunk neural crest cells, showing that the cavefish tissue environment is conducive for pigment cell development, and implicating intrinsic changes in cavefish neural crest cells in loss of body pigmentation. It is concluded that changes in neural crest cells play key roles in the evolution of cavefish development.

Understanding molecular evolution and development of the organ of Corti can provide clues for hearing restoration

Abstract

The mammalian hearing organ is a stereotyped cellular assembly with orderly innervation: two types of spiral ganglion neurons (SGNs) innervate two types of differentially distributed hair cells (HCs). HCs and SGNs evolved from single neurosensory cells through gene multiplication and diversification. Independent regulation of HCs and neuronal differentiation through expression of basic Helix-loop-Helix transcription factors (bHLH TFs: Atoh1, Neurog1, Neurod1) led to the evolution of vestibular HC assembly and their unique type of innervation. In ancestral mammals, a vestibular organ was transformed into the organ of Corti (OC) containing a single row of inner HC (IHC), three rows of outer HCs (OHCs), several unique supporting cell types, and a peculiar innervation distribution. Restoring the OC following long-term hearing loss is complicated by the fact that the entire organ is replaced by a flat epithelium and requires reconstructing the organ from uniform undifferentiated cell types, recapitulating both evolution and development. Finding the right sequence of gene activation during development that is useful for regeneration could benefit from an understanding of the OC evolution. Toward this end, we report on Foxg1 and Lmx1a mutants that radically alter the organ of Corti (OC) cell assembly and its innervation when mutated and may have driven the evolutionary reorganization of the basilar papilla into an organ of Corti in ancestral Therapsids. Furthermore, genetically manipulating the level of bHLH TFs changes HC type and distribution and allows inference how transformation of HCs might have happened evolutionarily. We report on how bHLH TFs regulate OHC/IHC and how misexpression (Atoh1-Cre; Atoh1f/kiNeurog1) alters HC fate and supporting cell development. Using mice with altered HC types and distribution, we demonstrate innervation changes driven by HC patterning. Using these insights, we speculate on necessary steps needed to convert a random mixture of postmitotic precursors into the orderly OC through spatially and temporally regulated critical bHLH genes in the context of other TFs to restore normal innervation patterns.

An approach for phycoremediation of different wastewaters and biodiesel production using microalgae

Abstract

Four microalgal strains, namely, Tetraselmis indica (T. indica), Scenedesmus abundans (S. abundans), Spirulina sp., and Nostoc muscorum (N. muscorum) were cultivated on four different wastewaters in 1000 ml photobioreactors with 750 ml working volume under 94.5 μmol m⁻² s⁻¹ light intensity for 14 days for phycoremediation of wastewaters and sustainable biodiesel production. These microalgal strains attained maximum biomass growth in the secondary treated sewage (STS). Maximum biomass yield (0.6533 g L⁻¹) and lipid productivity (25.44 mg L⁻¹ d⁻¹) for T. indica were achieved in STS. T. indica removed (63.6–78.24%) of nitrate, (60.90–65.97%) of phosphate, (61.01–80.01%) of ammonical nitrogen, and (71.16–85.70%) of total organic carbon (TOC) in all four wastewaters. The fatty acid methyl ester (FAME) profile of T. indica shows the presence of myristic acid (1.2%) pentadecylic acid (0.28%), palmitic acid (10.32%), oleic acid (34.59%), linoleic acid (12.38%), and eicosanoic acid (14.88%) in STS. This study demonstrates that T. indica is the most suitable microalgal species among the four microalgal strains selected for phycoremediation of wastewaters and higher biomass production for sustainable biodiesel production.

Heavy metal availability, bioaccessibility, and leachability in contaminated soil: effects of pig manure and earthworms

Abstract

A pot experiment and a leaching experiment were conducted to investigate the effects of earthworms and pig manure on heavy metals (Cd, Pb, and Zn) immobility, in vitro bioaccessibility and leachability under simulated acid rain (SAR). Results showed manure significantly increased soil organic carbon (SOC), dissolved organic carbon (DOC), available phosphorus (AP), total N, total P and pH, and decreased CaCl₂-extractable metals and total heavy metals in water and SAR leachate. The addition of earthworms significantly increased AP (from 0.38 to 1.7 mg kg⁻¹), and a downward trend in CaCl₂-extractable and total leaching loss of heavy metals were observed. The combined earthworm and manure treatment decreased CaCl₂-extractable Zn, Cd, and Pb. For Na₄P₂O₇-extractable metals, Cd and Pb were decreased with increasing manure application rate. Application of earthworm alone did not contribute to the remediation of heavy metal polluted soils. Considering the effects on heavy metal immobilization and cost, the application of 6% manure was an alternative approach for treating contaminated soils. These findings provide valuable information for risk management during immobilization of heavy metals in contaminated soils.

Interplay between elemental imbalance-related PI3K/Akt/mTOR-regulated apoptosis and autophagy in arsenic (III)-induced jejunum toxicity of chicken

Abstract

Arsenic trioxide (As₂O₃), the most toxic form of arsenic found in foodstuffs, is considered a carcinogen for human and animal. But many of the events that occur during its passage through the gastrointestinal tract are uncharted in birds. This study assesses the toxic effect on the jejunum of chicken which subchronically exposed to diets that contain As₂O₃ (0, 0.625, 1.25, 2.5 mg/kg body weight) for 90 days. Electron microscopy, TdT-mediated dUTP nick-end labeling (TUNEL), qPCR, and Western blot were performed. The results showed that mitochondrial fusion and apoptosis inhibiting genes had degressive trends, whereas mitochondrial fission and apoptosis activating genes presented heightened expressions in the treatment group compared with the control (P < 0.05). Subsequently, significant inhibition in PI3K/AKT/mTOR signaling was observed. Moreover, the expression of autophagy markers (LC3-II/LC3-I, Beclin-1) increased time and dose-dependently. Additionally, metabolic disorders of trace elements were detected evidenced by their significant decreases (aluminum, silicon, calcium, manganese, strontium, titanium, lithium, boron, cobalt, mercury, chromium) and increases (arsenic, cadmium, selenium, lead, nickel) on 90 days using inductively coupled plasma mass spectrometer (ICP-MS). It is possible that the changes of trace elements have a hand in the come on and development of arsenism. Taken together, we conjectured that, in chicken jejunum, arsenic led to redistribution of trace elements, promoting apoptosis via regulating mitochondrial dynamics, leading to autophagy through PI3K/AKT/mTOR signal pathways.

A patchwork epistemology of disagreement?

Abstract

The epistemology of disagreement standardly divides conciliationist views from steadfast views. But both sorts of views are subject to counterexample—indeed, both sorts of views are subject to the same counterexample. After presenting this counterexample, I explore how the epistemology of disagreement should be reconceptualized in light of it.

Ammonia production in poultry houses can affect health of humans, birds, and the environment—techniques for its reduction during poultry production

Abstract

Due to greater consumption of poultry products and an increase in exports, more poultry houses will be needed. Therefore, it is important to investigate ways that poultry facilities can coexist in close proximity to residential areas without odors and environmental challenges. Ammonia (NH₃) is the greatest concern for environmental pollution from poultry production. When birds consume protein, they produce uric acid, ultimately converted to NH₃ under favorable conditions. Factors that increase production include pH, temperature, moisture content, litter type, bird age, manure age, relative humidity, and ventilation rate (VR). NH₃ concentration and emissions in poultry houses depend on VR; seasons also have effects on NH₃ production. Modern ventilation systems can minimize NH₃ in enclosed production spaces quickly but increase its emissions to the environment. NH₃ adversely affects the ecosystem, environment, and health of birds and people. Less than 10 ppm is the ideal limit for exposure, but up to 25 ppm is also not harmful. NH₃ can be minimized by housing type, aerobic and anaerobic conditions, manure handling practices, litter amendment, and diet manipulation without affecting performance and production. Antibiotics can minimize NH₃, but consumers have concerns about health effects. Administration of probiotics seems to be a useful replacement for antibiotics. More studies have been conducted on broilers, necessitating the need to evaluate the effect of probiotics on NH₃ production in conjunction with laying hen performance and egg quality. This comprehensive review focuses on research from 1950 to 2018.

The nexus between energy consumption and financial development: estimating the role of globalization in Next-11 countries

Abstract

In the modern era of globalization, the economic activities expand with the passage of time. This expansion may increase demand for energy both in developing and developed countries. Therefore, this study assesses the impact of financial development on energy consumption incorporating the role of globalization in Next-11 countries. A group of panel estimation techniques is used to analyze the panel data and time series data for the time 1990–2014. The empirical results of the study suggest that financial development stimulates energy consumption. Also, globalization increases demand for energy consumption, although the single country analysis suggests that the effect of globalization on energy demand is heterogeneous among N-11 countries. Furthermore, feedback hypothesis is confirmed between financial development and energy consumption. Also, bidirectional causality is found between economic growth and energy consumption. The findings urge for the attention of policymaker in emerging countries to develop a strategy to reduce the consequences of energy consumption by controlling resource transfer through globalization to the host country and by adopting energy conversation policies.

Degradation of polycyclic aromatic hydrocarbons (PAHs) during Sphagnum litters decay

Abstract

The dynamics of polycyclic aromatic hydrocarbon (PAH) degradation in Sphagnum litters and the decomposition of the litters were investigated. PAH concentration decreased to approximately half of the initial concentration as Sphagnum litters decayed. The initial PAH concentration was 489.2 ± 72.2 ng g⁻¹, and the concentration after 120 days of incubation was 233.0 ± 5.8 ng g⁻¹. The different PAH compositions changed concentrations at different times. The low-molecular-weight (LMW) and high-molecular-weight (HMW) PAHs started to be degraded after incubation and after 40 days of incubation, respectively. PAH concentrations in the Sphagnum litters correlated with the total organic carbon (TOC) content (p < 0.05), indicating that PAHs were associated with the TOC of the Sphagnum litters and were degraded as organic matter decayed. The positive relationship between LMW PAH concentration and the soluble carbohydrate content (p < 0.05) indicated that LMW PAHs and the readily decomposed organic carbon fractions were cometabolized, or that LMW PAHs were mainly absorbed by soluble carbohydrate. The weak negative correlation between fulvic acid (FA) and PAH concentrations (p < 0.1) indicated that FA may enhance PAH degradation. Redundancy analysis suggested that the contents of both soluble carbohydrate and cellulose significantly affected the changes in PAH concentrations (p < 0.05), and that FA content and C/N ratios may also contribute to the changes in PAH concentrations (p < 0.1). However, the polyphenol that was related to microbial activities was not associated with changes in PAH concentrations. These results suggested that litter quality is more important than microbial activities in PAH degradation in Sphagnum litters.