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Does variable stand structure associated with multi-cohort forests support diversity of ground beetle (Coleoptera, Carabidae) communities in the central Nearctic boreal forest？

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Journal of Forestry research 2016年第5期27卷 1191-1202页

作者： Erica P. Barkley Jay r. Malcolm Sandy M. smith M. Isabel Bellocq Faculty of Forestry University of Toronto 33 Willcocks Street Toronto ON M5S 3B3 Canada Departamento de Ecología Genética y Evolución IEGEBA(CONICET-UBA) Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires Buenos Aires Argentina

Multi-cohort management （MCM） that retains a range of stand structures （age and size class） has been proposed to emulate natural disturbance and improve management in the Nearctic boreal forest. Although MCM forests contain both single- and multi-aged stands of mixed tree sizes, little is known about how variable stand structure affects associated fauna and biodiversity. Here, we examine the relationship between ground beetle （Coleoptera, Carabidae） communities and stand characteristics across a range of forest structure （=cohort classes）. Given that MCM classes are defined by the distribution of their tree-stem diameters, we ask whether parameters associated with these distributions （Weibull） could explain observed variation in carabid communities, and if so, how this compares to traditional habitat variables such as stand age, foliage complexity or volume of downed woody debris. We sampled carabids using weekly pitfall collections and compared these with structural habitat variables across a range of cohort classes （stand structure and age since disturbance） in 18 sites of upland mixed boreal forests from central Canada. results showed that richness and diversity of carabid communities were similar among cohort classes. Weibull parameters from the diameter distribution of all stems were the strongest predictors of variation in carabid communities among sites, but vertical foliage complexity, understory thickness, and percentage of deciduous composition were also significant. The abundance of several carabid forest specialists was strongly correlated with tree canopy height, the presence of large trees, and high vertical foliage complexity. Our results demonstrate that variable forest structure, as expected under MCM, may be useful in retaining the natural range of ground beetle species across the central Nearctic boreal forest.

关键词： Biodiversity conservation Boreal forest Carabidae Forest structure Ground beetles Multi-cohortmanagement Tree diameter distribution

Utility of faecal calprotectin analysis in adult inflammatory bowel disease

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World Journal of Gastroenterology 2012年第46期18卷 6782-6789页

作者： Lyn A smith Daniel r Gaya Inflammatory Bowel Diseases Service Gastroenterology Unit Glasgow Royal Infirmary

The inflammatory bowel diseases (IBD), Crohn's disease and ulcerative colitis, are chronic relapsing, remitting disorders. Diagnosis, along with assessment of disease activity and prognosis present challenges to managing clinicians. Faecal biomarkers, such as faecal calprotectin, are a non-invasive method which can be used to aid these decisions. Calprotectin is a calcium and zinc binding protein found in the cytosol of human neutrophils and macrophages. It is released extracellularly in times of cell stress or damage and can be detected within faeces and thus can be used as a sensitive marker of intestinal inflammation. Faecal calprotectin has been shown to be useful in the diagnosis of IBD, correlates with mucosal disease activity and can help to predict response to treatment or relapse. With growing evidence supporting its use, over the last decade this faecal biomarker has significantly changed the way IBD is managed.

关键词： Faecal calprotectin Inflammatory bowel disease Crohn's disease Ulcerative colitis Faecal biomarker

Harnessing endothelial cells and vascularization strategies for nerve regeneration

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Neural regeneration research 2024年第11期19卷 2337-2338页

作者： Papon Muangsanit Poppy smith Virology and Cell Technology research Team National Center for Genetic Engineering and Biotechnology(BIOTEC)National Science and Technology Development Agency(NSTDA)PathumthaniThailand UCL Centre for Nerve Engineering UCLLondonUK Department of Pharmacology UCL School of PharmacyUCLLondonUK

Peripheral nerves are essential components of the human body’s communication system,transmitting signals between the central nervous system and various body *** resulting from trauma or disease can result in debilitating sensory and motor *** injuries,particularly those resulting in significant gaps in the nerve tissue,pose a formidable challenge for clinicians and *** their limitations,including limited availability and donor site morbidity,nerve autografts remain the clinical gold standard for treating nerve injuries.

关键词： injuries nerves donor

Investigation of a cyanine dye assay for the evaluation of the biocompatibility of magnesium alloys by direct and indirect methods

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Bioactive Materials 2020年第1期5卷 26-33页

作者： Afrah Al Hegy ryan smith Eric r.Gauthier Joy E.Gray-Munro Dept.of Chemistry and Biochemistry Laurentian UniversitySudburyOntarioP3E 2C6Canada

Magnesium and its alloys are promising candidates for a new generation of biodegradable metals in orthopaedic applications due to their excellent biocompatibility,biodegradability,and mechanical properties that are similar to natural ***,direct in vitro assessment of these materials in the presence of cells is complicated by degradation products from the alloy that lead to a false positive for the most commonly used cell adhesion and cell proliferation *** this paper,a cyanine dye was used to quantitatively evaluate the in vitro biocompatibility of a Mg AZ31 alloy by both direct and indirect *** cytotoxicity of the corrosion products was evaluated via an indirect method;a 25%decrease in cell viability compared to control samples was ***,direct assessment of cell adhesion and proliferation showed a statistically significant increase in cell number at the surface after 72 *** addition,the degradation rate and surface characteristics of the Mg AZ31 alloy were evaluated for both direct and indirect *** degradation rate was unaffected by the presence of cells while evidence of an increase in calcium phosphate deposition on the magnesium alloy surface in the presence of cells was *** study demonstrates that a cyanine dye based assay provides a more accurate assessment of the overall in vitro biocompatibility of biodegradable metals than the more commonly used assays reported in the literature to date.

关键词： Magnesium alloys Biocompatibility Direct method Indirect method Cyanine dye Cell adhesion Cell proliferation Cytotoxicity

Predicting the temporal transferability of model parameters through a hydrological signature analysis

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Frontiers of Earth Science 2020年第1期14卷 110-123页

作者： Dilhani Ishanka JAYATHILAKE Tyler.smith Institute for a Sustainable Environment Clarkson UniversityPotsdamNY 13699USA Department of Civil and Environmental Engineering Clarkson UniversityPotsdamNY 13699USA

Attention has recently increased on the use of hydrological signatures as a potential tool for assessing the fidelity of model structures and providing insights into the transfer of model *** utility of hydrological signatures as model performance/reliability indicators in a calibration-validation testing scenario(i.e.,the temporal transfer of model parameters)is the focus of this *** Probability Distributed Model,a flexible conceptual hydrological model,is used to test the approach across a number of catchments included in the MOPEX data set We explore the change in model performance across calibration and validation time periods and contrast it to the corresponding change in several hydrological signatures to assess signature *** are explored in finer detail by utilizing a moving window approach to calibration and validation time *** results of this study indicated that the most informative signature can vary,both spatially and temporally,based on physical and climatic characteristics and their interaction to the model ***,one signature could not adequately illustrate complex watershed behaviors nor predict model performance in new analysis periods.

关键词： streamflow hydrological signature validation testing model calibration

New prospects for computational hydraulics by leveraging high-performance heterogeneous computing techniques

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Journal of Hydrodynamics 2016年第6期28卷 977-985页

作者： Qiuhua LIANG Luke smith Xilin XIA Hebei University of Engineering Handan 056038 China School of Civil Engineering and Geosciences Newcastle University Newcastle upon Tyne UK

In the last two decades, computational hydraulics has undergone a rapid development following the advancement of data acquisition and computing technologies. Using a finite-volume Godunov-type hydrodynamic model, this work demonstrates the promise of modern high-performance computing technology to achieve real-time flood modeling at a regional scale. The software is implemented for high-performance heterogeneous computing using the OpenCL programming framework, and developed to support simulations across multiple GPUs using a domain decomposition technique and across multiple systems through an efficient implementation of the Message Passing Interface （MPI） standard. The software is applied for a convective storm induced flood event in Newcastle upon Tyne, demonstrating high computational performance across a GPU cluster, and good agreement against crowd- sourced observations. Issues relating to data availability, complex urban topography and differences in drainage capacity affect results for a small number of areas.

关键词： computational hydraulics high-performance computing flood modeling shallow water equations shock-capttLring hydrodynamic model

Polyethylene glycol fusion repair of severed sciatic nerves accelerates recovery of nociceptive sensory perceptions in male and female rats of different strains

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Neural regeneration research 2025年第9期20卷 2667-2681页

作者： Liwen Zhou Karthik Venkudusamy Emily A.Hibbard Yessenia Montoya Alexa Olivarez Cathy Z.Yang Adelaide Leung Varun Gokhale Guhan Periyasamy Zeal Pathak Dale r.Sengelaub George D.Bittner Department of Neuroscience University of TexasAustinTXUSA Program in Neuroscience Indiana UniversityBloomingtonINUSA Department of Molecular Biosciences University of TexasAustinTXUSA

Successful polyethylene glycol fusion(PEG-fusion)of severed axons following peripheral nerve injuries for PEG-fused axons has been reported to:(1)rapidly restore electrophysiological continuity;(2)prevent distal Wallerian Degeneration and maintain their myelin sheaths;(3)promote primarily motor,voluntary behavioral recoveries as assessed by the Sciatic Functional Index;and,(4)rapidly produce correct and incorrect connections in many possible combinations that produce rapid and extensive recovery of functional peripheral nervous system/central nervous system connections and reflex(e.g.,toe twitch)or voluntary *** preceding companion paper describes sensory terminal field reo rganization following PEG-fusion repair of sciatic nerve transections or ablations;howeve r,sensory behavioral recovery has not been explicitly explored following PEG-fusion *** the current study,we confirmed the success of PEG-fusion surgeries according to criteria(1-3)above and more extensively investigated whether PEG-fusion enhanced mechanical nociceptive recovery following sciatic transection in male and female outbred Sprague-Dawley and inbred Lewis *** nociceptive responses were assessed by measuring withdrawal thresholds using von Frey filaments on the dorsal and midplantar regions of the *** von Frey filament tests were a more reliable method than plantar von Frey filament tests to assess mechanical nociceptive sensitivity following sciatic nerve *** withdrawal thresholds of the sciatic-mediated lateral dorsal region differed significantly across strain but not *** thresholds did not change significantly from baseline in chronic Unoperated and Sham-operated *** sciatic transection,all rats exhibited severe hyposensitivity to stimuli at the lateral dorsal region of the hindpaw ipsilateral to the ***,PEG-fused rats exhibited significantly earlier return to baseline withdrawal thresholds than Negative

关键词： autophagia axotomy collateral sprouting neuropathic pain peripheral nerve repair polyethylene glycol fusion(PEG-fusion) saphenous nerve sensory neurons sex and strain Wallerian degeneration

Challenges in Understanding Genome-Wide DNA Methylation

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Journal of Computer Science & Technology 2010年第1期25卷 26-34页

作者：张伟奇 Andrew D. smith Cold Spring Harbor Laboratory Cold Spring Harbor Bioinformatics Division TNLIST and MOE Key Lab of Bioinformatics Tsinghua University Department of Biological Sciences University of Southern California

DNA methylation is a chemical modification of the bases in genomes. This modification, most frequently found at CpG dinucleotides in eukaryotes, has been identified as having multiple critical functions in broad and diverse species of animals and plants, while mysteriously appears to be lacking from several other well-studied species. DNA methylation has well known and important roles in genome stability and defense, its pattern change highly correlates with gene regulation. Much evidence has linked abnormal DNA methylation to human diseases. Most prominently, aberrant DNA methylation is a common feature of cancer genomes. Elucidating the precise functions of DNA methylation therefore has great biomedical significance. Here we provide an update on large-scale experimental technologies for detecting DNA methylation on a genomic scale. We also discuss new prospect and challenges that computational biologist will face when analyzing DNA methylation data.

关键词： DNA methylation epigenome computational epigenomics

Sex differences in the foraging behavior of a generalist hawkmoth

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Insect Science 2022年第1期29卷 304-314页

作者： Gordon P.smith Goggy Davidowitz ruben Alarcón Daniel r.Papaj Judith L.Bronstein Department of Ecology and Evolutionary Biology University of ArizonaTucsonArizonaUSA Department of Entomology University of ArizonaTucsonArizonaUSA Department of Biology California State University Channel IslandsCamarilloCaliforniaUSA Current address:Department of Neurobiology and Behavior Cornell UniversityIthacaNew YorkUSA

Within-species variation in pollinator behavior is widely observed, but its causes have been minimally investigated. Pollinator sex is associated with large differences in behavior that may lead to predictable differences in flower foraging, but this expectation has not been explicitly tested. We investigate sex-associated differences in nectar-foraging behavior of the hawkmoth Hyles lineata, using pollen on the proboscis as a proxy for flower visitation. We tested two predictions emerging from the literature: (1) the sexes differ in the flower species they visit, (2) females are more specialized in flower choice. We also examined potential drivers underlying these predictions by performing field and laboratory experiments to test whether males (3) switch among flower species more frequently, or (4) fly farther and therefore encounter more species than females. Consistent with prediction (1), pollen load composition differed between the sexes, indicative of visitation differences. Contrary to prediction (2), females consistently carried more species-rich pollen loads than males. (3) Both sexes switched between flower species at similar rates, suggesting that differences in floral fidelity are unlikely to explain why females are less specialized than males. (4) Males flew longer distances than females;coupled with larger between-site differences in pollen composition for females, this result suggests that sex differences in mobility influence foraging, and that females may forage more frequently and in smaller areas than males. Together, our results demonstrate that sex-associated foraging differences can be large and consistent over time, and highlight the importance of sex as a driver of variation in pollinator behavior.

关键词： hawkmoths intraspecific variation pollination sex differences