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Study of a damage constitutive model for water-bearing coal measures sedimentary rock with nonlinear deformation during compaction stage

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Geohazard Mechanics 2023年第3期1卷 244-254页

作者： Weinan Wang Qiangling Yao Aiwen Wang karen A.Hudson-Edwards Chuangkai Zheng Lun Yan Lianpeng Dai Yihong Liu Institute of Disaster Rock Mechanics Liaoning UniversityShenyang110036PR China State Key Laboratory of Coal Resources and Safe Mining China University of Mining&TechnologyXuzhou221116PR China Camborne School of Mines and Environment and Sustainability Institute University of ExeterPenrynTR109FEUK

The problem of repeated immersion-induced fatigue damage in engineering coal measures sedimentary rock,including coal-rock pillars,reservoir bank slopes,and water-rich tunnels at the boundary of coal mine underground reservoirs,has profound implications for their stability,safety,and operation,and can even lead to geological *** address this issue,this paper aims to construct a constitutive model that accurately captures the comprehensive process of deformation and failure in water-bearing coal measures sedimentary *** explores the deformation characteristics of these formations and provides a theoretical foundation for numerical simulations of geological disasters induced by water-rock *** study integrates the deformation mechanisms of void and matrix deformation in coal seam sedimentary rocks,while considering the influence of immersion ***,it formulates a segmented constitutive model to depict the entire process of deformation and failure in cyclically immersed water-bearing coal measures sedimentary rock under uniaxial *** proposed model's accuracy and rationality are validated through comparisons with experimental research findings and existing theoretical curves from similar *** results demonstrate the model's effectiveness in describing the deformation behavior of non-dense water-bearing coal measures sedimentary rock under uniaxial compression or low confining pressure before reaching peak stress,although further refinements may be necessary to precisely capture post-peak deformation *** parameters,including the deformation caused by voids(γ0)between voids,increase exponentially with immersion times,while the elastic modulus(Ev)of voids and the parameter(f0)related to the average strength of microelements decrease expo*** homogeneity degree(m)exhibits no discernible *** research outcomes provide valuable insights for the stability control of engineering coal

关键词： Cyclic immersion Water-rock interaction Void compaction Deformation characteristic Constitutive model

Evaluation of Size Structure in freshwater Cyanobacterial Populations: Methods to Quantify Risk Associated with Changes in Biomass and Microcystin Concentrations

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Journal of Water Resource and Protection 2019年第6期11卷 810-829页

作者： Nancy J. Leland James f. Haney Kristin Conte karen Malkus-Benjamin Bryan Horsely Lim-Tex North Andover MA USA Department of Zoology University of New Hampshire Durham NH USA Manchester Water Works Manchester NH USA Town of Barnstable Barnstable MA USA Association to Preserve Cape Cod Dennis MA USA

Cyanobacterial populations in surface waters, including drinking water supplies and recreational waters, represent an ever present challenge for resource managers. As communities continuously respond to external and internal processes, dynamic profiles of composition, dominance, growth and toxigenicity emerge. In this study measures of size structure and biomass, quantified using light microscopy and fluorometry, were used to estimate microcystin concentrations through linear regression analysis. Toxigenic profiles using cyanobacterial biomass were developed for lakes dominated by Microcystis spp. and Dolichospermum spp., influenced by both genus-specific pigment concentrations as well as microcystin concentrations. Community composition (Log %MIC) and biomass were used to describe microcystin concentrations in mixed assemblages, where composition was the first input variable. The accessory photopigment phycocyanin was used to describe the linear relationship between the daily growth and net microcystin production rates in the bloom-forming Microcystis spp. samples, suggesting that this size-fractionated sample may provide indications of potential toxigenicity in the whole lake water sample. future investigations using fluorometric evaluation of cyanobacterial populations could provide additional applications and metrics for use by resource managers to quantify risk association with elevated cyanotoxin concentrations.

关键词： Microcystis Dolichospermum Phycocyanin Microcystins Growth Rates

Managing hybridization of a recovering endangered species： The red wolf Canis rufus as a case study

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Current Zoology 2015年第1期61卷 191-205页

作者： Eric M. GESE fred f. KNOWLTON Jennifer R. ADAMS karen BECK Todd K. fULLER Dennis L. MURRAY Todd D. STEURY Michael K. STOSKOPf Will T. WADDELL Lisette P. WAITS USDA/APHIS/WS/National Wildlife Research Center Department of Wildland Resources Utah State University Logan UT 84322-5230 USA Department offish and Wildlife Sciences University of Idaho Moscow Idaho 83844-1136 USA Environmental Medicine Consortium College of Veterinary Medicine North Carolina State University Raleigh NC 27606 USA Department of Environmental Conservation 160 Holdsworth Way University of Massachusetts Amherst MA 01003-9285 USA Department of Biology Trent University 1600 West Bank Drive Peterborough Ontario K9J 7B8 Canada School of forestry and Wildlife Sciences Auburn University Auburn AL 36849 USA Point Defiance Zoo and Aquarium 5400 North Pearl Street Tacoma WA 98407 USA

Hybridization presents a unique challenge for conservation biologists and managers. While hybridization is an important evolutionary process, hybridization is also a threat formany native species. The endangered species recovery effort for the red wolf Canis rufus is a classic system for understanding and addressing the challenges of hybridization. from 1987-1993, 63 red wolves were released from captivity in eastern North Carolina, USA, to establish a free-ranging, non-essential experimental population. By 1999, managers recognized hybridization with invasive coyotes Canis latrans was the single greatest threat to successful recovery, and an adaptive management plan was adopted with innovative approaches for managing the threat of hybridization. Here we review the application and results of the adaptive management efforts from 1993 to 2013 by comparing: (1) the numbers of wolves, coyotes, and hybrids captured, (2) the numbers of territorial social groups with presumed breeding capabilities, (3) the number of red wolf and hybrid litters documented each year and (4) the degree of coyote introgression into the wild red wolf gene pool. We documented substantial increases in the number of known red wolves and red wolf social groups from 1987-2004 followed by a plateau and slight decline by *** number of red wolf litters exceeded hybrid litters each year and the proportion of hybrid litters per year averaged 21%. The genetic composition of the wild red wolf population is estimated to include from recent introgression since reintroduction. We conclude that the adaptive management plan was effective at reducing the introgression of coyote genes into the red wolf population, but population recovery of red wolves will require continuation of the current management plan, or alternative approaches, for the foreseeable future. More broadly, we discuss the lessons learned from red wolf adaptive management that could assist other endangered species recov

关键词：物种管理濒危物种狼犬杂交适应性管理案例北卡罗来纳州实验种群

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孕期母猫和新生幼猫的营养学综述

畜牧产业 2022年第2期 56-61页

作者：张云阳(译) 米雁(译) francisco Antonio félix Xavier Júnior karen Denise da Silva Macambira Steffi Lima Araujo 亘泰集团上海吉宠(上海)国际贸易有限公司上海不详

猫营养学知识及其影响动物健康有关知识是兽医学的一大实际内容。由于日粮管理可防止许多器官系统的某些疾病的发展,并有助于治疗某些胃肠道疾病和其他疾病,因此人们在日粮管理领域的投资日益增多。因为猫的日粮会根据其生理阶段和营养... 详细信息

猫营养学知识及其影响动物健康有关知识是兽医学的一大实际内容。由于日粮管理可防止许多器官系统的某些疾病的发展,并有助于治疗某些胃肠道疾病和其他疾病,因此人们在日粮管理领域的投资日益增多。因为猫的日粮会根据其生理阶段和营养需求存在差异,因此猫营养界定很重要。众所周知,不同生理阶段的营养差异甚至比同一生理阶段不同物种的差异更明显。与犬相比,猫的营养管理方面有着很多不同之处。由于日粮中蛋白质和脂质的含量取决于必需维生素和矿物质含量,了解猫科动物的营养需求对于配制营养均衡、健康的日粮至关重要,从而可为动物提供更长的预期寿命和高质量生活。本研究旨在对家猫最重要的营养方面进行文献综述,重点介绍在其不同生理阶段对日粮进行妥善管理的需求。

关键词：小动物营养猫新生幼崽

Mesenchymal stromal cells from human perinatal tissues: from biology to cell therapy

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World Journal of Stem Cells 2010年第4期2卷 81-92页

作者： karen Bieback Irena Brinkmann Institute of Transfusion Medicine and Immunology Medical Faculty Mannheim Heidelberg University DRK-Blutspendedienst Baden-Württemberg Hessen gGmbH Ludolf-Krehl-Str. 13-17 D-68167 Mannheim Germany

Cell-based regenerative medicine is of growing interest in biomedical research. The role of stem cells in this context is under intense scrutiny and may help to define principles of organ regeneration and develop innovative therapeutics for organ failure. Utilizing stem and progenitor cells for organ replacement has been conducted for many years when performing hematopoietic stem cell transplantation. Since the first successful transplantation of umbilical cord blood to treat hematological malignancies, non-hematopoietic stem and progenitor cell populations have recently been identified within umbilical cord blood and other perinatal and fetal tissues. A cell population entitled mesenchymal stromal cells (MSCs) emerged as one of the most intensely studied as it subsumes a variety of capacities: MSCs can differentiate into various subtypes of the mesodermal lineage, they secrete a large array of trophic factors suitable of recruiting endogenous repair processes and they are *** on perinatal tissues to isolate MSCs, we will discuss some of the challenges associated with these cell types concentrating on concepts of isolation and expansion, the comparison with cells derived from other tissue sources, regarding phenotype and differentiation capacity and finally their therapeutic potential.

关键词： Mesenchymal stromal cells Umbilical cord Cord blood Regenerative medicine Cell therapy Stem cells Amnion Chorion Perinatal Discarded tissue fetal membranes

Spliceosomal genes in the *** genome:a comparison with those in ***,***,*** and ***

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Protein & Cell 2011年第5期2卷 395-409页

作者： Bing Yu Petra fey karen E.Kestin-Pilcher Alexei fedorov Ashwin Prakash Rex L.Chisholm Jane Y.Wu Department of Molecular and Clinical Genetics Royal Prince Alfred Hospital and Sydney Medical School(Central)the University of SydneyNSW 2006Australia dictyBase Center for Genetic MedicineNorthwestern UniversityChicagoIL 60611USA Department of Neurology and Lurie Comprehensive Cancer Center Center for Genetic MedicineNorthwestern University Feinberg Medical SchoolChicagoIL 60611USA Department of Medicine and Program in Bioinformatics and Proteomics/Genomics The University of ToledoToledoOH 43614USA

Little is known about pre-mRNA splicing in Dictyostelium discoideum although its genome has been completely *** analysis suggests that pre-mRNA splicing plays an important role in *** gene expression as two thirds of its genes contain at least one *** curation of the genome to date has revealed 40 genes in *** with clear evidence of alternative splicing,supporting the existence of alternative splicing in this unicellular *** identified 160 candidate U2-type spliceosomal proteins and related factors in *** based on 264 known human genes involved in *** small ribonucleoproteins(snRNPs),PRP19 complex proteins and late-acting proteins are highly conserved in *** and throughout the *** non-snRNP and hnRNP families,*** orthologs are closer to those in ***,*** and *** than to their counterparts in *** splicing regulators,including SR proteins and CUGbinding proteins,were found in ***,but not in *** comprehensive catalog of spliceosomal proteins provides useful information for future studies of splicing in *** where the efficient genetic and biochemical manipulation will also further our general understanding of pre-mRNA splicing.

关键词： pre-mRNA splicing spliceosomal genes Dictyostelium discoideum comparative genomics splicing regulators

Prescription for Obesity: Eat Less and Move More. Is It Really That Simple?

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Open Journal of Nursing 2014年第9期4卷 656-662页

作者： karen M. Deck Beth Haney Camille f. fitzpatrick Susanne J. Phillips Susan M. Tiso Core faculty Graduate Nursing Programs University of California Irvine Irvine CA USA

“Obesity is a disease.” This is the declaration by the American Medical Association in June, 2013. The purpose of this article is to provide an overview of options for patients who meet the criteria of obesity. Primary care nurse practitioners are urged to confront obesity head on, with early, individualized intervention to reduce associated morbidity and mortality. Options for weight loss and maintenance are abundant and often confusing or unattractive to the patient. Working with patients to achieve realistic, reasonable, and patient-tailored goals for weight loss and exercise programs are paramount to achieving a healthy weight and lifestyle.

关键词： Obesity Management Options

A Culture-Independent and Culture-Dependent Study of the Bacterial Community from the Bedrock Soil Interface

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Advances in Microbiology 2015年第13期5卷 842-857页

作者： karen Olsson-francis Carl P. Boardman Victoria K. Pearson Paul f. Schofield Anna Oliver Stephen Summers Department of Environment Earth and Ecosystems The Open University Milton Keynes UK Department of Engineering and Innovation The Open University Milton Keynes UK Department of Physical Sciences The Open University Milton Keynes UK Department of Earth Sciences Natural History Museum London UK NERC Centre for Ecology and Hydrology Wallingford UK

In nutrient limited soils, minerals constitute a major reservoir of bio-essential elements. Consequently, the release of nutritive elements during weathering is crucial. Bacteria have been shown to enhance weathering rates;however, there has been limited work that has focused on the bacterial weathering of bedrock or parent rock, which are the major sources of minerals, in nutrient limiting soils. In this study, both a culture-independent and culture-dependent approach was used to study the bacterial community at the interface between basaltic bedrock and nutrient limiting soil in Cadiar Idris region of Snowdonia National Park, United Kingdom. High throughput sequencing method, Ion Torrent, was used to characterise the bacterial community, which generated over 250,000 sequences. Taxonomical assignment demonstrated that approximately 50% (125,000 sequences) of the community consisted of the orders Actinomycetales, Burkholderiales, Clostridales, Bacillales, Rhizobiales and Acidobacterium, with unclassified sequences representing 44% ± 1.46% (110,000 ± 3650). Bacteria belonging to the genera Serratia, Pseudomonas, Bacillus, Paenibacillus, Chromobacterium, Janthinobacterium, Burkholderia and Arthrobacter, were isolated from the sample site. All of the isolates were able to grow in a minimal growth medium, which contained glucose, ammonium chloride with basalt as the sole source of bio-essential elements. Seventy percent of the isolates significantly enhanced basalt dissolution (p f dissolution correlated to the production of oxalic acid and acidification of the growth medium. The findings of this work suggest that at the interface between bedrock and soil heterotrophic members of the bacterial community can enhance weathering, an essential part of biogeochemical cycling in nutrient limiting soil.

关键词： Mineral Weathering Soil Microbial Communities Basalt Dissolution

Delirium,insulin-like growth factor I,growth hormone in older inpatients

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World Journal of Psychiatry 2020年第9期10卷 212-222页

作者： Dimitrios Adamis Iulian Coada Piet Eikelenboom Che-Sheng Chu karen finn Vincent Melvin John Williams David James Meagher Geraldine McCarthy Department of Psychiatry Sligo/Leitrim Mental Health ServicesSligo F91 CD34Ireland Department of Psychiatry Research and Academic Institute of AthensAthens 11742Greece Department of Psychiatry University Hospital LimerickLimerick V94 F858Ireland Department of Psychiatry GGZinGeest and VuMCAmsterdam 1081 HVthe Netherlands Department of Psychiatry and Center for Geriatric and Gerontology Kaohsiung Veterans General HospitalKaohsiung 81362Taiwan Department of Biopharmaceutical and Medical Science School of Science and ComputingGalway-Mayo Institute of TechnologyGalway H91 T8NWIreland Department of Pathology Sligo University HospitalSligo F91 H684Ireland

BACKGROUND Delirium is a common disorder in elderly medical inpatients with serious adverse outcomes and is characterized by sudden onset,disturbance in attention,awareness,consciousness and cognition,and often with behavioural *** to understanding delirium,is understanding mechanisms by which body and brain wellbeing are linked and in particular how brain responses to bodily homeostatic stress is mediated.A number of studies have investigated the relationship between insulin-like growth factor I(IGf-I)and delirium in medically ill hospitalised patients with conflicting ***,none have investigated growth hormone(GH)which is related to IGf-I via negative *** To investigate the relationship between serum levels of IGf-I and GH,and the occurrence of *** Prospective,longitudinal,observational *** elderly inpatients(aged 70+),were assessed twice weekly with Montreal cognitive assessment(MoCA),Confusion assessment method(CAM),Acute Physiology and Chronic Health Evaluation *** was defined using *** history of dementia was evaluated with the Informant Questionnaire on Cognitive Decline in the ***-I and GH levels were estimated with the ELISA *** estimating equations(GEE)model was applied for the first five assessments to analyze those longitudinal *** The sample consisted of 198 participants(mean age 80.63±6.81;range 70-97).Of these 92(46.5%)were *** six(43.4%)were identified with a history of *** or prevalent delirium during hospitalisation was identified with CAM in 40 participants(20.2%).Evaluation of missing values with Little's MCAR test indicated that they were missing completely at random(MCARχ2=12.24,u:9,P=0.20).Using GEE for the analysis we found that low MoCA scores,low levels of IGf-I and high levels of GH were significantly associated with any delirium(prevalence,incident,or fluctuating,during the study period(Waldχ2=12.231;u:

关键词： Delirium Pathophysiology Insulin-like growth factor-I Growth hormone Older people Physical illness Cognition Old age psychiatry