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关键词： Physarum polycephalum   TiO2 nanoparticles   Metabolic intervention   Transcriptomics   Metabolomics   DNA-DAMAGE   OXIDATIVE STRESS   PERTURBATIONS   ADAPTATION   RESPONSES   SURVIVAL   ACID   OVEREXPRESSION   NANOMATERIALS   PROLIFERATION  

摘要： Concerns about the environmental and human health implications of TiO2 nanoparticles (nTiO(2)) are growing with their increased use in consumer and industrial products. Investigations of the underlying molecular mechanisms of nTiO(2) tolerance in organisms will assist in countering nTiO(2) toxicity. In this study, the countermeasures exhibited by the slime mold Physarum polycephalum macroplasmodium against nTiO(2) toxicity were investigated from a physiological, transcriptional, and metabolic perspective. The results suggested that the countermeasures against nTiO(2) exposure include gene-associated metabolic rearrangements in cellular pathways involved in amino acid, carbohydrate, and nucleic acid metabolism. Gene-associated nonmetabolic rearrangements involve processes such as DNA repair, DNA replication, and the cell cycle, and occur mainly when macroplasmodia are exposed to inhibitory doses of nTiO(2). Interestingly, the growth of macroplasmodia and mammal cells was significantly restored by supplementation with a combination of responsive metabolites identified by metabolome analysis. Taken together, we report a novel model organism for the study of nTiO(2) tolerance and provide insights into countermeasures taken by macroplasmodia in response to nTiO(2) toxicity. Furthermore, we also present an approach to mitigate the effects of nTiO(2) toxicity in cells by metabolic intervention. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Bioreactor   Degradation   Landfill   Methane   Municipal solid waste   METHANE PRODUCTION   CO-DIGESTION   LEACHATE RECIRCULATION   ANAEROBIC-DIGESTION   INDUSTRIAL SLUDGE   LANDFILL-SITES   SEWAGE-SLUDGE   REFUSE   WATER   DECOMPOSITION  

摘要： The objective of this study was to evaluate waste biodegradation and biochemical compatibility for different waste co-disposed with municipal solid waste (MSW). Laboratory-scale reactors were operated with MSW co-disposed with special solid waste, liquid waste, or sludge waste. Early and aggressive addition of liquid wastes during reactor startup did not stimulate anaerobic decomposition of fresh MSW. The majority of the liquid waste reactors were acid stuck and had leachate pH < 6 and chemical oxygen demand in the range of 50,000 mg-O-2/L. The majority of liquid wastes in this study were not observed to be effective anaerobic inoculums and would not be recommended as the sole moisture source for bioreactor landfills. Enhanced early methane production was observed in the MSW reactors co-disposed with sludge (anaerobic and industrial) relative to the landfill leachate control reactors and all other waste combinations evaluated. Methane generation was observed in reactors operated with foundry waste or gypsum board co-disposed with MSW. Despite biochemical methane potential (BMP) results that indicated methane generation would be inhibited with these two waste streams, co-disposing with MSW did not completely inhibit anaerobic degradation. The BMP assays provided methane yield under ideal conditions, but did not capture other benefits of co-disposal (e.g., impacts of moisture addition). A potential co-disposal waste source should not be ruled out by BMP results alone. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Wattle fence   Soil stabilization   Erodibility indices   Carbon sequestration   Microbial biomass carbon   DIFFERENT LAND USES   EROSION CONTROL   MICROBIAL BIOMASS   ALPINE GRASSLANDS   VEGETATION   ERODIBILITY   STORAGE   IMPACTS   PLANT   DEGRADATION  

摘要： Eroded bare land stabilization is important to reduce soil erosion and stimulate soil carbon (C) sequestration for improved soil biogeochemical quality in hillslope soils. This study investigated the effectiveness of wattle fencing as a bioengineering tool to improve soil stabilization, soil physico-chemical properties and soil organic C dynamics and reduce soil erodibility in the Boyabat mountain regions of Turkey with rough and over-steepened slope (50?70%). Wattle fence treatments were developed in the area of 50 ha in the spring season of 2010 and surface (0?20 cm) and subsurface soil (20?40 cm) samples were taken in Spring, 2015. Results revealed that, compared to control with bare slope, wattle fencing significantly improved some soil physico-chemical, and microbial properties and erodibility indices by increasing clay ratio, dispersion ratio and aggregate stability index in surface and subsoils. Wattle fencing enhanced plant available water contents more in surface than in subsoils. Wattle fencing also increased microbial biomass C contents by 55% and 43% in surface and subsurface soils, respectively. Soil organic C followed similar trends; however, they were indifferent between sampling depths for the control soils. Soil organic C stocks and aggregate stability index were significantly positively correlated and seemed to be better predictor of positive effects of wattle fencing on soil structural stability, erodibility and associated properties. We found positive effects of soil organic C contents on microbial biomass C and soil-water relations suggesting restoration of soil biological functions and favorable influence on soil water retention following wattle fencing. Although sparse vegetation was observed in the research area, our study emphasizes performing further research to understand the effects of wattle fencing along with afforestation with native vegetation on soil erosion rates on a long-term basis by considering the variability in edaphic and env

关键词： Hydrothermal carbonisation   HTC   Hemp   Compositional analysis   Hemicellulose   Cellulose   Lignin  

摘要： Hydrothermal carbonisation (HTC) is a technology used to convert biomass and other feedstocks into a highenergy ?hydrochar? with numerous potential applications in solid fuels, activated carbons, and carbon sequestration, among others. The conversion of lignocellulosic biomasses involves a complex, interconnected set of reactions that result in the breakdown of hemicellulose, cellulose and lignin, the precise mechanisms and kinetics of which are at present poorly understood. Hemp stem and seed hulls are subjected to HTC at three temperatures (200 ?C, 230 ?C, 260 ?C), and four residence times (0, 15, 30, 60 min), and the hydrochars produced were analysed for hemicellulose, cellulose and lignin content. The degradation for each macromolecule was characterised using Arrhenius kinetics, and it was found that hemicellulose degraded rapidly with a 1.3rd order reaction, while cellulose degraded more slowly. A portion of lignin in each hemp tissue was found to be inert under HTC conditions; hull lignin degraded rapidly to a constant level of 31% in a first order reaction, while two models were built describing stem lignin, one with an assumed inert portion of 34%, and another with an assumed inert portion of 21%.

关键词： phase separation   reentrant phase transitions   disordered proteins   transcription   RNA   condensates   PRION-LIKE DOMAINS   RNA-BINDING PROTEINS   POLYMERASE-II   SEPARATION   FUS   DYNAMICS   REGULATOR   GRANULES   CLUSTERS   BEHAVIOR  

摘要： Appreciation for the role of liquid-liquid phase separation in the functional organization of cellular matter has exploded in recent years. More recently there has been a growing effort to understand the principles of heterotypic phase separation, the demixing of multiple proteins and nucleic acids into a single functional condensate. A phase transition is termed reentrant if it involves the transformation of a system from one state into a macroscopically similar or identical state via at least two phase transitions elicited by variation of a single parameter. Reentrant liquid-liquid phase separation can occur when the condensation of one species is tuned by another. Reentrant phase transitions have been modeled in vitro using protein and RNA mixtures. These biochemical studies reveal two features of reentrant phase separation that are likely important to functional cellular condensates: (1) the ability to generate condensates with layered functional topologies, and (2) the ability to generate condensates whose composition and duration are self-limiting to enable a form of biochemical timekeeping. We relate these biochemical studies to potential cellular examples and discuss how layered topologies and self-regulation may impact key biological processes. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Catalase   Copper   Glutathione S-transferase   Metallothionein   Superoxide dismutase   OXYGEN SPECIES PRODUCTION   FISH OREOCHROMIS-NILOTICUS   FRESH-WATER   HEAVY-METALS   HEALTH-RISK   MULTIVARIATE-ANALYSIS   CHANNA-PUNCTATUS   RIVER   MARINE   INDUCTION  

摘要： Fish can be highly vulnerable to environmental pressures because they are exposed to oxidative stressors in the aquatic environment. Such stressors can affect the levels of antioxidant biomarkers against reactive oxygen species (ROS). With this study we investigated the oxidative stress ecology in Danube barbel (Barbus balcanicus) from the Barbucina creek (northeast Italy), a watercourse in the Collio winegrowing district. To do this, superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) activity was measured in gills, liver, and muscle, while metallothioneins (MT) and trace and rare earth elements (REEs) levels were determined in muscle. The effect of environmental factors (physicochemical parameters of water, trace elements and REEs) on oxidative stress biomarkers was thus assessed. High concentrations were determined for cerium (Ce), scandium (Sc), neodymium (Nd), lanthanum (La), yttrium (Y), and praseodymium (Pr) among the REEs. Among the trace elements, arsenic (As), copper (Cu), and mercury (Hg) levels were higher compared to published data, suggesting their role as stressors. The multiple linear regression (MLR) model showed a statistically significant association (R-2 = 0.858; F = 10.07; p = 0.015) between As, Cu, Hg, and Pr and SOD activity in the gills, indicating a functional relationship between them. Differently, CAT activity was significantly higher in the liver, probably in response to long-term Cu contamination of the watercourse. This was confirmed by the MLR model that showed a significant association (R-2= 0.638: F = 8.152; p = 0.02) between the concentration of MT and of Cu. Our data show a biochemical defensive response by Danube barbel to the disturbances in the aquatic ecosystem of the Barbucina creek. These insights advance our understanding of the role and the effects of environmental fac tors as trace elements and REEs on oxidative stress in fish. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Time scale analysis   Characteristic times   Modeling-based design   Microscale-based technology   MASS-TRANSFER   PROCESS INTENSIFICATION   GROWTH-KINETICS   TAYLOR FLOW   METHANOL   BUBBLES   GAS   MICROCHANNELS   TECHNOLOGIES   CONVERSION  

摘要： Time-Scale Analysis and Characteristics Times are suggested as a novel and useful tool for analyzing the performance of microscale-based bioreactors with immobilized bioactive material (e.g. enzymes or microbial species), and plant flow-sheet diagrams of chemical processes. Transport rates, reaction kinetics, and phase contacting can be easily represented by unique time constants, which facilitate understanding and representation of these processes via the ?heat-map tableau? of Characteristic Times. Details related to the development and the origin of Characteristic Times are presented in Part I of this paper; Jovanovic et al. (2020). Time Scale Analysis & Characteristic Times is a technical approach germane to process improvement, where it facilitates the discovery of areas in need of process intensification. The feasibility and usefulness of this novel tool is demonstrated by considering a microbial biochemical reaction process performed in a traditional bioreactor vs. performance in a microscale-based bioreactor design and evaluating the balance of characteristic times associated with each technology. We believe that this technical approach will confidently find its place in the toolbox of practicing chemical reaction engineers. ? 2021 Elsevier Ltd. All rights reserved.

关键词： Named entity recognition   Deep learning   Bi-directional Long Short-Term Memory (BILSTM)   Conditional Random Field (CRF)   Bidirectional Encoder Representations from Transformers (BERT)   Multi-Head Attention (MHATT)   LSTM-CRF   ATTENTION   MODEL   NETWORKS  

摘要： Named entity recognition (NER) of chemicals and drugs is a critical domain of information extraction in biochemical research. NER provides support for text mining in biochemical reactions, including entity relation extraction, attribute extraction, and metabolic response relationship extraction. However, the existence of complex naming characteristics in the biomedical field, such as polysemy and special characters, make the NER task very challenging. Here, we propose a hybrid deep learning approach to improve the recognition accuracy of NER. Specifically, our approach applies the Bidirectional Encoder Representations from Transformers (BERT) model to extract the underlying features of the text, learns a representation of the context of the text through Bi-directional Long Short-Term Memory (BILSTM), and incorporates the multi-head attention (MHATT) mechanism to extract chapter-level features. In this approach, the MHATT mechanism aims to improve the recognition accuracy of abbreviations to efficiently deal with the problem of inconsistency in full-text labels. Moreover, conditional random field (CRF) is used to label sequence tags because this probabilistic method does not need strict independence assumptions and can accommodate arbitrary context information. The experimental evaluation on a publicly-available dataset shows that the proposed hybrid approach achieves the best recognition performance; in particular, it substantially improves performance in recognizing abbreviations, polysemes, and low-frequency entities, compared with the state-of-the-art approaches. For instance, compared with the recognition accuracies for low-frequency entities produced by the BILSTM-CRF algorithm, those produced by the hybrid approach on two entity datasets (MULTIPLE and IDENTIFIER) have been increased by 80% and 21.69%, respectively. (c) 2021 Elsevier B.V. All rights reserved.