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Biochar and Compost Increase Crop Yields but the Effect is Short Term on Sandplain Soils of Western Australia

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Pedosphere 2015年第5期25卷 720-728页

作者： david J.m.HALL Richard W.BELL Department of Agriculture and Food School of Veterinary and Life Sciences Murdoch University

Sandplain soils on the south coast of Western Australia have low inherent fertility, which is mainly due to poor nutrient retention caused by insufficient clay and organic colloidal material. Previous research has shown the benefits in nutrient levels and retention from adding clay to sandplain soils; however, there is almost no information on the addition of organic amendments. A field experiment was established at the Esperance Downs Research Station, Western Australian, in may 2010, to assess the effects of wheat straw(WS) and chicken manure(Cm) biochars and compost with and without phosphorus(P) addition on soil properties and crop production over five growing seasons. The five seasons alternated between winter and summer crops. The Cm and WS biochar and compost treatments significantly increased crop yields and P uptake in 3, 2 and 1 of the five seasons, respectively. The yield increases(P more than 8%. By the end of the third season, no differences in crop yields were found that could be attributed to the organic amendments. The addition of P increased crop yields in each winter cropping season. Phosphorus addition explained more than 30%of the variation in crop yields. Despite marginal P levels and summer drought conditions, arbuscular mycorrhizal root colonisation was not affected by the organic amendments. There were no significant interactions between the organic amendments and P addition in terms of crop yields, P uptake or P uptake efficiency. We conclude that much of the effect of the organic amendments was due to direct nutrient addition which dissipated over time.

关键词： mycorrhizal root colonisation nutrient retention organic amendments P addition P uptake

Functional diversity of small-mammal postcrania is linked to both substrate preference and body size

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Current Zoology 2020年第5期66卷 539-553页

作者： Lucas N.Weaver david m.Grossnickle Department of Biology Life Sciences BuildingUniversity of WashingtonSeattleWA 98195USA

Selective pressures favor morphologies that are adapted to distinct ecologies,resulting in trait partition!ng among ***,the effects of these selective pressures vary across taxa,especially because morphology is also influenced by factors such as phylogeny,body size,and functional *** this study,we examine how these factors impact functional diversification in *** has been proposed that trait partitioning among mammalian ecomorphotypes is less pronoun ced at small body sizes due to biomecha nical,energetic,and environ mental factors that favor a"generalist"body plan,whereas larger taxa exhibit more substantial functional *** title this the Diverge nee Hypothesis(DH)because it predicts greater morphological divergence among ecomorphotypes at larger body *** test DH by using phylogenetic comparative methods to examine the postcranial skeletons of 129 species of taxonomically diverse,small-tomedium-sized(mammals,which we categorize as either"tree-dwellers"or"ground-dwellers."In some analyses,the morphologies of ground-dwellers and tree-dwellers suggest greater between-group differentiation at larger sizes,providing some evidence for ***,this trend is n either particularly strong nor supported by all an *** stead,a more pronoun ced patter n emerges that is distinct from the predictions of DH:within-group phenotypic disparity increases with body size in both ground-dwellers and tree-dwellers,driven by morphological outliers among"medium'-sized ***,evolutionary increases in body size are more closely linked to increases in within-locomotor-group disparity tha n to in creases in betwee n-group *** discuss biomechanical and ecological factors that may drive these evolutionary patter ns,and we emphasize the significant evolutionary influences of ecology and body size on phenotypic diversity.

关键词： adaptive landscapes ecomorphology morphometries phenotypic diversity phylogenetic comparative methods trait partitioning

Rationally designed synthesis of bright AgInS2/ZnS quantum dots with emission control

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Nano Research 2020年第9期13卷 2438-2450页

作者： Jose X.Soares K.david Wegner david S.m.Ribeiro Armindo melo Ines Hausler Joao L.m.Santos Ute Resch-Genger LAQV-REQUImTE Department of Chemical SciencesLaboratory of Applied ChemistryFaculty of PharmacyUniversity of PortoRua de Jorge Viterboferreira228Porto4050-313Portugal Federal Institute for materials Research and Testing(BAm) Division BiophotonicsRichard-Willstaetter-Strasse 1112489 BerlinGermany LAQV-REQUImTE Laboratorio de Bromatologia e HidrologiaDepartamento de Ciencias QutmicasFaculdade de Farmacia da Universidade do PortoRua de Jorge Viterboferreira228Porto4050-313Portugal Technische Universitat Berlin Institutfiir Optik und Atomare PhysikStrafie des 17.Juni 13510623 BerlinGermany

In the blossoming field of Cd-free semiconductor quantum dots(QDs),ternary Ⅰ-Ⅲ-VI QDs have received increasing attention due to the ease of the environmentally friendly synthesis of high-quality materials in water,their high photoluminescence(PL)quantum yields(QYs)in the red and near infrared(NIR)region,and their inherently low ***,their oxygen-insensitive long PL lifetimes of up to several hundreds of nanoseconds close a gap for applications exploiting the compound-specific parameter PL *** overcome the lack of reproducible synthetic methodologies and to enable a design-based control of their PL properties,we assessed and modelled the synthesis of high-quality mPA-capped AglnS2/ZnS(AlS/ZnS)*** refined parameters included reaction time,temperature,Ag:In ratio,S:In ratio,Zn:In ratio,mPA:ln ratio,and pH using a design-of-experiment *** for the optimization was provided by mathematical models developed for the application-relevant PL parameters,maximum PL wavelength,QY,and PL lifetime as well as the elemental composition in terms of Ag:ln:Zn *** these experimental data-based models,mPA:ln and Ag:ln ratios and pH values were identified as the most important synthesis parameters for PL control and an insight into the connection of these parameters could be ***,the experimental conditions to synthetize QDs with tunable emission and high QY were *** excellent agreement between the predicted and experimentally found PL features confirmed the reliability of our methodology for the rational design of high quality AlS/ZnS QDs with defined PL *** approach can be straightforwardly extended to other ternary and quaternary QDs and to doped QDs.

关键词： quantum dot core/shell nanoparticle silver indium sulfide microw ave-assisted synthesis design of experim ent photoluminescence

Recovery rates of persistent post-COVID-19 olfactory dysfunction using psychophysical assessment:A longitudinal cohort study

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 79-87页

作者： Jeremy P.Tervo Patricia T.Jacobson Brandon J.Vilarello Tiana m.Saak Francesco F.Caruana Liam W.Gallagher Joseph B.Gary david A.Gudis Paule V.Joseph D.P.Devanand Terry E.Goldberg Jonathan B.Overdevest Columbia University Vagelos College of Physicians and Surgeons New YorkNew YorkUSA Department of Otolaryngology-Head and Neck Surgery New York-Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA Department of Otolaryngology-Head and Neck Surgery University of PittsburghPittsburghPennsylvaniaUSA Department of Otolaryngology-Head and Neck Surgery University of MinnesotaMinneapolisMinnesotaUSA National Institute of Alcohol Abuse and Alcoholism Section of Sensory Science and Metabolism&National Institute of Nursing ResearchBethesdaMarylandUSA New York-Presbyterian/Columbia University Irving medical Center New YorkNew YorkUSA

Objectives:Persistent olfactory dysfunction(OD)following loss of smell associated with SARS-CoV-2 infection is a major feature of long *** on the prevalence of persistent OD predominantly rely on self-reported olfactory *** studies have tracked longitudinal rates of recovery using psychophysical assessment among patients presenting for evaluation of persistent OD beyond a window of acute *** anchored in standardized testing methods are needed to counsel patients who fail to acutely regain their sense of *** study aims to quantify the degree of persistent OD in post-COVID-19 patients who experience subjective and psychophysical ***:We grouped participants presenting for OD evaluation into cohorts based on both subjective and psychophysical olfactory status at a baseline assessment and assessed their olfactory abilities with a visual analogue scale and the Sniffin'Sticks extended test at baseline and 1-year time *** had confirmed a history of COVID-19 by lab evaluation or clinical diagnosis if lab evaluation was not ***:Baseline olfactory evaluation was completed by 122 participants,53 of whom completed the 1-year follow-up *** participants presenting with perceived OD,74.5%had confirmed psychophysical OD at baseline,with 55.1%at 1-year *** had reliable trends in self-rated versus psychophysically tested olfactory function at both time *** total threshold,discrimination,and identification(TDI)score improved by+3.25 points in the cohort with psychophysical OD(p=0.0005),with this improvement largely attributable to an increase in median threshold scores(+2.75 points;p=0.0004).Conclusions:OD persists in a significant number of patients who fail to acutely recovery their sense of smell after COVID-19,with many demonstrating lingering deficits at *** in threshold,but not discrimination or identification,most significantly mediate improvement

关键词： long COVID olfaction post-COVID condition smell dysfunction

Giant mineral deposits：Introduction

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Geoscience Frontiers 2016年第3期7卷 299-301页

作者： m.Santosh david I.Groves China University of Geosciences Beijing 100083 China Department of Earth Sciences University of Adelaide SA 5005 Australia Centre for Exploration Targeting UWA Crawley WA 6009 Australia

Giant,and to a lesser extent world-class,mineral deposits are the ultimate exploration targets,with discovery changing the financial bottom line of junior exploration companies and providing long-term resources and re... 详细信息

关键词： REE

Gene duplication plays a major role in gene co-option: Studies into the evolution of the motilin/ghrelin family and their receptors

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Chinese Science Bulletin 2011年第25期56卷 2690-2697页

作者： HE Jing Irwin m. david ZHANG YaPing State Key Laboratory of Genetic Resource and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Department of Laboratory medicine and Pathobiology and Banting and Best Diabetes Centre University of Toronto Toronto M5S1A1 Canada Laboratory for Conservation and Utilization ofBioresource Yunnan University Kunming 650091 China

Extant genes can be modified, or 'tinkered with', to provide new roles or new characteristics of these genes. At the genetic level, this often involves gene duplication and specialization of the resulting genes into particular functions. We investigate how ligand-receptor partnerships evolve after gene duplication. While significant work has been conducted in this area, the examination of additional models should help us better understand the proposed models and potentially reveal novel evolutionary patterns and dynamics. We use bioinformatics, comparative genomics and phylogenetic analyses to show that preproghrelin and prepromotilin descended from a common ancestor and that a gene duplication generated these two genes shortly after the divergence of amphibians and amniotes. The evolutionary history of the receptor family differs from that of their cognate ligands. GPR39 diverges first, and an ancestral receptor gives rise to receptors classified as fish-specific clade A, GHSR and mLNR by successive gene duplications occurring before the divergence of tetrapods and ray-finned fish. The ghrelin/GHSR system is maintained and functionally conserved from fish to mammals. motilin-mLNR specificity must have arisen by ligand-receptor coevolution after the mLN hormone gene diverged from the GHRL gene in the amniote lineage. Conserved molecular machinery can give rise to new neuroendocrine response mechanisms by the co-option of duplicated genes. Gene duplication is both parsimonious and creative in producing elements for evolutionary tinkering and plays a major role in gene co-option, thus aiding the evolution of greater biological complexity.

关键词：基因重复生长素胃动素受体选项演变家庭进化模式

Influence of size effect and boundary conditions on temperature overshooting in nanoscale thermal conduction

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Chinese Science Bulletin 2014年第12期59卷 1334-1339页

作者： Xuefang Li mingtian Xu david m.Christopher Key Laboratory for Thermal Science and Power Engineering of ministry of Education Tsinghua University Institute of Thermal Science and Technology Shandong University

The temperature overshooting phenomenon in one-dimensional nanoscale heat conduction in thin films is studied for various boundary *** results show that when ballistic heat transport strongly affects the heat transport process,temperature overshooting is more likely to occur.A sudden increase of temperature on only one surface of a thin film cannot trigger temperature overshooting,while symmetric boundary temperature perturbations lead to the largest temperature *** heat conduction is also studied in a nanoscale *** analytic results show that Fourier’s law may severely underestimate the temperatures in nanofilms as well as in nanoareas when temperature overshooting occurs.

关键词：边界温度过冲现象边界条件纳米级热传导尺寸效应纳米薄膜热传递过程

Constipation-predominant irritable bowel syndrome: A review of current and emerging drug therapies

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World Journal of Gastroenterology 2014年第27期20卷 8898-8909页

作者： Khaled A Jadallah Susan m Kullab david S Sanders Department of Internalmedicine King Abdullah University Hospital Faculty of medicine Jordan University of Science and Technology Department of Gastroenterology and Liver Unit Royal Hallamshire Hospital Sheffield South Yorkshire S102JF United Kingdom

Irritable bowel syndrome(IBS) is a highly prevalent medical condition that adversely affects patient quality of life and constitutes a significant economic burden on healthcare resources. A large proportion of patients suffer from the constipation subtype of IBS(IBS-C), most commonly afflicting older individuals and those with a lower socioeconomic status. Conventional pharmacologic and nonpharmacologic treatment options have limited efficacies and/or significant adverse events, which lead to increased long-term health care expenditures. Failure to effectively treat IBS-C patients over the past decades has largely been due to a poor understanding of disease pathophysiology, lack of a global view of the patient, and an inappropriate selection of patients and treatment endpoints in clinical trials. In recent years, however, more effective and safer drugs have been developed for the treatment of IBS-C. The advancement in the area of pharmacologic treatment is based on new knowledge of the pathophysiologic basis of IBS-C and the development of drugs with increased selectivity within pharmacologic classes with recognized efficacies. This narrative review covers the spectrum of available drugs and their mechanisms of action, as well as the efficacy and safety profiles of each as determined in relevant clinical trials that have investigated treatment options for IBS-C and chronic constipation. A brief summary of laxative-based treatment options is presented, followed by up-to-date assessments for three classes of drugs: prokinetics, prosecretory agents, and bile acid modulators.

关键词： Constipation Irritable bowel syndrome Drug therapy Serotonergic agents Prokinetics 5-hydroxytryptamine type 4 agonists Secretagogues Prosecretory agents Bile acid modulators

The compelling link between physical activity and the body's defense system

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Journal of Sport and Health Science 2019年第3期8卷 201-217页

作者： david C.Nieman Laurel m.Wentz Human Performance Laboratory Appalachian State University North Carolina Research Campus Department of Nutrition and Health Care management Appalachian State University

This review summarizes research discoveries within 4 areas of exercise immunology that have received the most attention from investigators :(1) acute and chronic effects of exercise on the immune system,(2) clinical benefits of the exercise—immune relationship,(3) nutritional influen?ces on the immune response to exercise, and(4) the effect of exercise on immunosenescence. These scientific discoveries can be organized into distinctive time periods: 1900-1979, which focused on exercise-induced changes in basic immune cell counts and function; 1980-1989, during which seminal papers were published with evidence that heavy exertion was associated with transient immune dysfunction, elevated inflammatory biomarkers,and increased risk of upper respiratory tract infections; 1990-2009, when additional focus areas were added to the field of exercise immunology including the interactive effect of nutrition, effects on the aging immune system, and inflammatory cytokines; and 2010 to the present, when technological advances in mass spectrometry allowed system biology approaches(i.e., metabolomics, proteomics, lipidomics, and microbiome characterization) to be applied to exercise immunology studies. The future of exercise irmmunology will take advantage of these technologies to provide new insights on the interactions between exercise, nutrition, and immune function, with application down to the person?alized level. Additionally, these methodologies will improve mechanistic understanding of how exercise-induced immune perturbations reduce the risk of common chronic diseases.

关键词： Aging Exercise Immunology Infection Inflammation mass Snectrometry Nutrition