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Pathophysiological mechanisms underlying gastrointestinal symptoms in patients with COVID-19

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World journal of Gastroenterology 2021年第19期27卷 2341-2352页

作者： Byungchang jin Rajan Singh Se Eun Ha Hannah Zogg paul j Park Seungil Ro Department of Physiology and Cell Biology University of Nevada School of MedicineRenoNV 89557United States Department of Medicine Renown HealthRenoNV 89557United States

Gastrointestinal(GI)symptoms,such as diarrhea,abdominal pain,vomiting,and anorexia,are frequently observed in patients with coronavirus disease 2019(COVID-19).However,the pathophysiological mechanisms connecting these GI symptoms to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infections remain *** studies indicate that the entry of SARS-CoV-2 into intestinal cells leads to downregulation of angiotensin converting enzyme 2(ACE2)receptors resulting in impaired barrier *** intestinal ACE2 functions as a chaperone for the amino acid transporter B0AT1,the B0AT1/ACE2 complex within the intestinal epithelium acts as a regulator of gut microbiota composition and *** to the B0AT1/ACE2 complex lead to microbial dysbiosis through increased local and systemic immune *** studies have also suggested that altered serotonin metabolism may be the underlying cause of GI disorders involving *** findings of elevated plasma serotonin levels and high fecal calprotectin in COVID-19 patients with diarrhea indicate that the viral infection evokes a systemic inflammatory response that specifically involves the ***,the elevated proinflammatory cytokines correlate with elevated serotonin and fecal calprotectin levels further supporting the evidence of GI inflammation,a hallmark of functional GI ***,the finding that rectal swabs of COVID-19 patients remain positive for SARS-CoV-2 even after the nasopharynx clears the virus,suggests that viral replication and shedding from the GI tract may be more robust than that of the respiratory tract,further indicating fecal-oral transmission as another important route of viral *** review summarized the evidence for pathophysiological mechanisms(impaired barrier function,gut inflammation,altered serotonin metabolism and gut microbiota dysbiosis)underlying the GI symptoms in patients with COVID-19.

关键词： COVID-19 Gastrointestinal symptoms Gut microbiota dysbiosis Impaired barrier function Serotonin Angiotensin converting enzyme 2 receptor

Biomass-Derived Porous Carbon-Based Nanostructures for Microwave Absorption

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Nano-Micro Letters 2019年第2期11卷 81-97页

作者： Huanqin Zhao Yan Cheng Wei Liu Lieji Yang Baoshan Zhang Luyuan paul Wang Guangbin ji Zhichuan j.Xu College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China School of Materials Sciences and Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore Singapore-HUj Alliance for Research and Enterprise NEW-CREATE Phase IICampus for Research Excellence and Technological Enterprise(CREATE)Singapore 138602Singapore

Currently,electromagnetic(EM) pollution poses severe complication toward the operation of electronic devices and biological *** this end,it is pertinent to develop novel microwave absorbers through compositional and structural *** carbon(PC)materials demonstrate great potential in EM wave absorption due to their ultralow density,large surface area,and excellent dielectric loss ***,the large-scale production of PC materials through low-cost and simple synthetic route is a *** PC materials through biomass sources is a sustainable,ubiquitous,and low-cost method,which comes with many desired features,such as hierarchical texture,periodic pattern,and some unique *** the bio-inspired microstructure to manufacture PC materials in mild condition is *** this review,we summarize the EM wave absorption application of biomass-derived PC materials from optimizing structureand designing *** corresponding synthetic mechanisms and development prospects are discussed as *** perspective in this field is given at the end of the article.

关键词： Biomass resource Porous carbon Microwave absorption

Ecological monophagy in Tasmanian Graphium macleayanum moggana with evolutionary reflections of ancient angiosperm hosts

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Insect Science 2006年第6期13卷 451-460页

作者： j. MARK SCRIBER GEOFF R. ALLEN paul W. WALKER School of Agricultural Science/TIAR University of Tasmania Hobart Australia Department of Entomology Michigan StateUniversity East Lansing Michigan USA

Local host plant specialization in an insect herbivore may be caused by numerous factors, including host-specific natural enemy pressures or a local lack of suitable host-plant choices that are available elsewhere in its range. Such local specialization or ＂ecological monophagy＇, for whatever reason, may reflect reduced ability to behaviourally accept or physiologically utilize other allopatric hosts that are naturally used elsewhere by the species. We tested this feeding specialization hypothesis using the Tasmanian subspecies of Macleay＇s swallowtail butterfly, Graphium macleayanum moggana （Papilionidae）, which uses only a single host-plant species, Antherosperma moschatum （southern sassafras, of the Monlmiaceae）. Further north, this same butterfly species （G. m. macleayanum） uses at least 13 host-plant species from seven genera and four families （Lauraceae, Rutaceae, Winteraceae, and Monlmiaceae）. Our larval feeding assays with G. m. moggana from Tasmania showed that certain Magnoliaceae and Lauraceae could support some larval growth to pupation. However, such growth was slower and survival was lower than observed on their normal southern sassafras host （Monimiaceae）. We also found that toxicity of particular plant species varied tremendously within plant families （for both the Magnoliceae and the Monlmiaceae）.

关键词： Antherosperma detoxification Lauraceae Magnoliaceae Monimiaceae Papilionldae phytochemistry Rutaceae specialist swallowtail butterflies Winteraceae

Structure-guided Capacitance Relationships in Oxidized Graphene Porous Materials Based Supercapacitors

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Energy & Environmental Materials 2023年第4期6卷 58-69页

作者： Srinivas Gadipelli Hanieh Akbari juntao Li Christopher A.Howard Hong Zhang paul R.Shearing Dan j.L.Brett College of Physics Sichuan UniversityChengdu 610064China Electrochemical Innovation Lab Department of Chemical EngineeringUniversity College LondonLondonWC1E 7JEUK Department of Physics and Astronomy University College LondonLondonWC1E 6BTUK

Supercapacitors formed from porous carbon and graphene-oxide(GO)materials are usually dominated by either electric double-layer capacitance,pseudo-capacitance,or *** to these combined features,reduced GO materials have been shown to offer superior capacitance over typical nanoporous carbon materials;however,there is a significant variation in reported values,ranging between 25 and 350 F g^(−1).This undermines the structure(e.g.,oxygen functionality and/or surface area)-performance relationships for optimization of cost and scalable *** work demonstrates important structure-controlled charge storage *** this,a series of exfoliated graphene(EG)derivatives are produced via thermal-shock exfoliation of GO precursors and following controlled graphitization of EG(GEG)generates materials with varied amounts of porosity,redox-active oxygen groups and graphitic *** results show significantly varied capacitance values between 30 and 250 F g^(−1)at 1.0 A g^(−1)in GEG structures;this suggests that for a given specific surface area the redox-active and hydrophilic oxygen content can boost the capacitance to 250–300%higher compared to typical mesoporous carbon *** with identical oxygen functionality show a surface area governed *** allows to establish direct structure-performance relationships between 1)redox-active oxygen functional concentration and capacitance and 2)surface area and capacitance.

关键词： electric double-layer capacitance graphene-oxide pseudocapacitance structure-performance relationships supercapacitors

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水平地面变方向行走步态研究

中国生物医学工程学报 1998年第4期17卷 350-354页

作者：陈小安 paul,j.P 重庆大学

本文用ＶＩＣＯＮ运动分析系统研究日常活动中单侧负重条件下，常人水平地面变方向行走的步态，重点分析了步态循环周期中各步相的特征以及地面对足的三维反作用力规律，并且与有关文献的结果进行了比较。

关键词：步态变方向行走反作用力

A framework for the regional critical zone classi?cation: the case of the Chinese Loess Plateau

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National Science Review 2019年第1期6卷 14-18页

作者： Yihe Lü jian Hu Bojie Fu paul Harris Lianhai Wu Xiaolin Tong Yingfei Bai Alexis j.Comber State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences joint Center for Global Change Studies Institute of Qinghai-Tibetan Plateau Southwest Minzu University Sustainable Agriculture Sciences Rothamsted Research

The concept of the Earth’s Critical Zone(CZ)—the near-surface heterogeneous environment of our planet—was originally defined to include the land surface,vegetation canopy, rivers, lakes and shallow seas [1]. CZ accommodates interactions among air, water, soil, rock and living organisms, and determines the availability of life-sustaining resources needed for the well-being and sustainability of human society. Therefore, there are new opportunities for integrative studies of

关键词： the case of the Chinese Loess Plateau CLP CZ

Utilizing the ultrasensitive Schistosoma up-converting phosphor lateral flow circulating anodic antigen(UCP-LF CAA)assay for sample pooling-strategies

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Infectious Diseases of Poverty 2017年第1期6卷 1379-1391页

作者： paul L.A.M.Corstjens Pytsje T.Hoekstra Claudia j.de Dood Govert j.van Dam Department of Molecular Cell Biology Leiden University Medical CenterP.O.Box 96002300RCLeidenThe Netherlands Department of Parasitology Leiden University Medical CenterP.O.Box 96002300RCLeidenThe Netherlands

Background:Methodological applications of the high sensitivity genus-specific Schistosoma CAA strip test,allowing detection of single worm active infections(ultimate sensitivity),are discussed for efficient utilization in sample pooling *** relevant cost reduction,pooling of samples rather than individual testing can provide valuable data for large scale mapping,surveillance,and ***:The laboratory-based CAA strip test utilizes luminescent quantitative up-converting phosphor(UCP)reporter particles and a rapid user-friendly lateral flow(LF)assay *** test includes a sample preparation step that permits virtually unlimited sample concentration with urine,reaching ultimate sensitivity(single worm detection)at 100%*** facilitates testing large urine pools from many individuals with minimal loss of sensitivity and *** test determines the average CAA level of the individuals in the pool thus indicating overall worm burden and *** requiring test results at the individual level,smaller pools need to be analysed with the pool-size based on expected prevalence or when unknown,on the average CAA level of a larger group;CAA negative pools do not require individual test results and thus reduce the number of ***:Straightforward pooling strategies indicate that at sub-population level the CAA strip test is an efficient assay for general mapping,identification of hotspots,determination of stratified infection levels,and accurate monitoring of mass drug administrations(MDA).At the individual level,the number of tests can be reduced *** low endemic settings as the pool size can be increased as opposed to prevalence ***:At the sub-population level,average CAA concentrations determined in urine pools can be an appropriate measure indicating worm *** strategies allowing this type of large scale testing are feasible with the various CAA strip test formats and do not affect sens

关键词： Schistosomiasis Diagnostics Sample pooling Mass drug administration Circulating anodic antigen Lateral flow Strip test Up-converting reporter particle UCP-LF CAA

Vegetable Production After Flooded Rice Improves Soil Properties in the Red River Delta, Vietnam

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Pedosphere 2015年第1期25卷 130-139页

作者： Arij P.EVERAARTS jacques j.NEETESON Pham T.T.HUONG paul C.STRUIK Applied Plant Research Wageningen University and Research Centre Plant Research International Wageningen University and Research Centre Field Crop Research Institute Hai Duong and Hanoi University of Agriculture Centre for Crop Systems Analysis Wageningen University

Vegetable production in South East Asia often is in rotation with flooded rice. The puddling of the soil with flooded rice production may result in unfavourable soil conditions for the subsequent production of dry land crops. To establish whether permanent vegetable production results in favourable soil conditions for vegetables, the effects of five different permanent vegetable production systems and a system of vegetable production in rotation with flooded rice on soil properties after flooded rice were studied in a 2-year field experiment. Bulk density at 0.05–0.10 m depth layer decreased with permanent vegetable production and vegetable production in rotation with flooded rice. The decrease in bulk density was influenced by the application of organic manure and rice husks, and especially by the number of crops cultivated, suggesting that frequency of soil tillage had a major effect on bulk density. Ploughing with buffalo traction after flooded rice, in combination with construction of raised beds, could reduce or totally eliminate negative effects of puddling on soil structure. Bulk density at 0.15–0.20 m soil depth was not influenced. Soil acidity decreased significantly in all systems. Soil organic carbon increased in all systems, but significant increase was only found in two permanent vegetable production systems. Available phosphorus(P) significantly increased in two permanent vegetable production systems, with a positively correlation to the amount of P applied. The significant decrease in bulk density and increase in p H(H2O), after only 2 years, showed that soil conditions after flooded rice could be improved in a short time under intensive vegetable production.

关键词： available phosphorus bulk density organic carbon puddling soil fertility soil improvement

Malnutrition in cirrhosis:More food for thought

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World journal of Hepatology 2020年第11期12卷 883-896页

作者： Brooke Chapman Marie Sinclair paul j Gow Adam G Testro Nutrition and Dietetics Department Austin HealthHeidelberg 3084Australia Liver Transplant Unit Austin HealthHeidelberg 3084Australia

Malnutrition is highly prevalent in liver cirrhosis and its presence carries important prognostic *** clinical conditions and pathophysiological mechanisms that cause malnutrition in cirrhosis are multiple and *** and liver decompensation symptoms lead to poor dietary intake;metabolic changes characterised by elevated energy expenditure,reduced glycogen storage,an accelerated starvation response and protein catabolism result in muscle and fat wasting;and,malabsorption renders the cirrhotic patient unable to fully absorb or utilise food that has been *** is therefore a considerable challenge to manage effectively,particularly as liver disease progresses.A high energy,high protein diet is recognised as standard of care,yet patients struggle to follow this recommendation and there is limited evidence to guide malnutrition interventions in cirrhosis and liver *** this review,we seek to detail the factors which contribute to poor nutritional status in liver disease,and highlight complexities far greater than“poor appetite”or“reduced oral intake”leading to *** also discuss management strategies to optimise nutritional status in this patient group,which target the inter-related mechanisms unique to advanced liver ***,future research requirements are suggested,to develop effective treatments for one of the most common and debilitating complications afflicting cirrhotic patients.

关键词： Malnutrition Cirrhosis Liver transplantation Chronic liver disease Nutrition Sarcopenia