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Soil water content and nitrogen differentially correlate with multidimensional leaf traits of two temperate broadleaf species

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Plant Diversity 2023年第6期45卷 694-701页

作者： Ming-Yue jin Daniel j.johnson Guang-Ze jin Qing-Xi Guo Zhi-Li Liu Center for Ecological Research Key Laboratory of Sustainable ForestEcosystem Management-Ministry of EducationNortheast Asia Biodiversity Research CenterNortheast Forestry UniversityHarbin 150040HeilongjiangChina School of Forest Resources and Conservation University of FloridaGainesvilleFLUSA

The variation and correlation of leaf economics and vein traits are crucial for predicting plant ecological strategies under different environmental changes.However,correlations between these two suites of traits and abiotic factors such as soil water and nitrogen content remain ambiguous.We measured leaf economics and vein traits as well as soil water and nitrogen content for two different shade-tolerant species(Betula platyphylla and Acer mono)in four mixed broadleaved-Korean pine(Pinus koraiensis)forests along a latitudinal gradient in Northeast China.We found that leaf economics traits and vein traits were decoupled in shade-intolerant species,Betula platphylla,but significantly coupled in a shadetolerant species,A.mono.We found stronger correlations among leaf traits in the shade tolerant species than in the shade intolerant species.Furthermore,leaf economic traits were positively correlated with the soil water gradient for both species,whereas vein traits were positively correlated with soil water gradient for the shade intolerant species but negatively correlated in the shade tolerant species.Although economic traits were positively correlated with soil nitrogen gradient in shade intolerant species but not correlated in shade tolerant species,vein traits were negatively correlated with soil nitrogen gradient in shade tolerant species but not correlated in shade intolerant species.Our study provides evidence for distinct correlations between leaf economics and vein traits and local abiotic factors of species differing in light demands.We recommend that the ecological significance of shade tolerance be considered for species when evaluating ecosystem functions and predicting plant responses to environmental changes.

关键词： Leaf trait multidimensionality Economics traits Vein traits Soil water content Soil total nitrogen Shade tolerance

British journal of General Practice论文摘要汇编——英国初级保健中全科医生健康状况及职业倦怠与患者安全的关系:一项横断面调查

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中国全科医学 2019年第27期22卷 3297-3297页

作者： HALL L H johnson j WATT I 本刊编辑部(整理) School of Psychology University of Leeds Leeds and Yorkshire Quality and Safety Research Group Bradford Institute for Health Research Bradford Bradford. Department of Health Sciences University of York York and Hull York Medical School York. School of Psychology University of Leeds Leeds.

背景全科医生的健康状况不佳时职业倦怠水平较高。虽然在二级保健中,全科医生健康状况、职业倦怠水平与患者安全的相关性较差,但在初级保健中,尚未进行两者与患者安全关系的定量研究。此外,关于职业需求、职业倦怠及健康与患者安全关联... 详细信息

背景全科医生的健康状况不佳时职业倦怠水平较高。虽然在二级保健中,全科医生健康状况、职业倦怠水平与患者安全的相关性较差,但在初级保健中,尚未进行两者与患者安全关系的定量研究。此外,关于职业需求、职业倦怠及健康与患者安全关联的研究较少。目的通过调查职业变量(职业需求和支持)对全科医生健康状况和职业倦怠的影响,说明其是否与全科医疗中的患者安全相关联。设计与场所 2016年3月—2017年8月,在英国进行的一项横断面调查。方法共有232名全科医生完成了在线或纸质调查,测量健康状况、职业倦怠、职业需求和支持以及患者安全。结果93.8%的全科医生被视为可能患有轻微精神疾病,94.7%的全科医生患有轻度(22.0%)或严重(72.7%)疲惫,86.8%的全科医生患有轻度(37.9%)或严重(48.9%)脱离接触。结构方程模型(SEM)分析显示,在行政工作和随时待命上花费的时间较多和在医疗实践中感受到的支持较少与健康状况不佳相关,在医疗实践中感受到的支持较少与健康状况不佳又与过去3个月内报告的未遂事故可能性较高有关。在行政工作上花费的时间较多、每天诊疗患者数量较多、感受到的支持较少与职业倦怠水平较高有关,其与患者安全较差相关。结论医疗实践和个人层面应进行变革,以完善更健康的医生和患者工作环境,进一步提高患者在全科医疗中的安全性。

关键词：健康状况全科医生职业倦怠横断面调查初级保健安全性患者论文摘要

Trees species’ dispersal mode and habitat heterogeneity shape negative density dependence in a temperate forest

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森林生态系统:英文版 2023年第5期10卷 589-596页

作者： Lishunan Yang Daniel j.johnson Zhichun Yang Xiaochao Yang Qiulong Yin Ying Luo Zhanqing Hao Shihong jia School of Ecology and Environment Northwestern Polytechnical UniversityXi’anShaanxi710072China Shaanxi Key Laboratory of Qinling Ecological Intelligent Monitoring and Protection Northwestern Polytechnical UniversityXi’anShaanxi710072China School of Forest Fisheriesand Geomatics SciencesUniversity of FloridaGainesvilleFLUSA School of Geography and Tourism Shaanxi Normal UniversityXi’anShaanxi710062China

Conspecific negative density dependence(CNDD)is a potentially important mechanism in maintaining species diversity.While previous evidence showed habitat heterogeneity and species’dispersal modes affect the strength of CNDD at early life stages of trees(e.g.,seedlings),it remains unclear how they affect the strength of CNDD at later life stages.We examined the degree of spatial aggregation between saplings and trees for species dispersed by wind and gravity in four topographic habitats within a 25-ha temperate forest dynamic plot in the Qinling Mountains of central China.We used the replicated spatial point pattern(RSPP)analysis and bivariate paircorrelation function(PCF)to detect the spatial distribution of saplings around trees at two scales,15 and 50 m,respectively.Although the signal was not apparent across the whole study region(or 25-ha),it is distinct on isolated areas with specific characteristics,suggesting that these characteristics could be important factors in CNDD.Further,we found that the gravity-dispersed tree species experienced CNDD across habitats,while for wind-dispersed species CNDD was found in gully,terrace and low-ridge habitats.Our study suggests that neglecting the habitat heterogeneity and dispersal mode can distort the signal of CNDD and community assembly in temperate forests.

关键词： Biodiversity Conspecific negative density dependence Dispersal Replicated point patterns Temperate forest Topographic habitat

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X100钢管运行试验的技术标准和制造

焊管 2014年第6期37卷 68-72页

作者：徐婷 johnson j HUDSON M 中国石油集团石油管工程技术研究院西安710077

以一段直径为1 219 mm、压力为18 MPa的X100管线作为试验运行段,对其进行了力学性能试验。试验结果表明,此试验段能够满足技术规范的要求,关键力学性能良好,横向和纵向的拉伸性能最大偏差为35 MPa;-20℃时母材最小韧性超过了180 j,-30... 详细信息

以一段直径为1 219 mm、压力为18 MPa的X100管线作为试验运行段,对其进行了力学性能试验。试验结果表明,此试验段能够满足技术规范的要求,关键力学性能良好,横向和纵向的拉伸性能最大偏差为35 MPa;-20℃时母材最小韧性超过了180 j,-30℃焊缝韧性超过了117 j,实现了对裂纹起始控制的要求;管体、焊缝和HAZ硬度均低于300HV10,在正常条件、极端条件及高设计因子条件下均可满足长期运行要求。

关键词：焊管 X100钢级管线钢力学性能

Sodium lanthanide fluoride core-shell nanocrystals： A general perspective on epitaxial shell growth

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Nano Research 2013年第8期6卷 547-561页

作者： Noah j. j. johnson Frank C. j. M. van Veggel Department of Chemistry University ofVictoria P.O. Box3065 Victoria British Columbia Canada V8W 3V6

理解结构的特征和生长机制为与特殊性质产生核心壳 nano-heterostructures 是必要的。特别在基于 lanthanide 的 nanocrystals，核心壳作文的合理设计能被利用提高 / 调节最后的 nanostructure 的光性质，或能被用来集成多重功能的应用... 详细信息

理解结构的特征和生长机制为与特殊性质产生核心壳 nano-heterostructures 是必要的。特别在基于 lanthanide 的 nanocrystals，核心壳作文的合理设计能被利用提高 / 调节最后的 nanostructure 的光性质，或能被用来集成多重功能的应用程序(例如，光 / 磁性) 。在这篇文章，我们在钠 lanthanide 在我们取向附生的壳生长的当前的理解考察进步氟化物(NaLnF4 ) nanocrystals。以便理解取向附生的壳生长核心 nanocrystals 不得不一致，并且标明日期高质量的近一致的尺寸 / 形状分散的合成基于 lanthanide 的 nanocrystals 的控制合成主要与 nanocrystals 的这个班被完成了。在在 nanocrystals (NaLnF4 ) 的这个班上的核心壳合成和取向附生的壳生长机制的进步被考察，并且一个一般观点基于不同描述技术在核心壳形态学上被提供。当在在各种各样的功能的应用程序学习核心壳结构的影响有巨大的进步时，在我们看来，这评论也加亮控制核心壳形态学的方法的仍然有限的理解，它强调尚待被探讨最大化他们的性能的一些重要、未答复的问题。

关键词：稀土氟化物纳米晶体外延生长核壳控制合成外壳钠生长机制

Convergence of the turkey gut microbiota following cohabitation under commercial settings

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journal of Animal Science and Biotechnology 2021年第4期12卷 1635-1644页

作者： Elizabeth A.Miller Brittanie Winfield Bonnie P.Weber Cristian Flores-Figueroa jeannette Munoz-Aguayo jared Huisinga Timothy j.johnson Department of Veterinary and Biomedical Sciences University of MinnesotaSaint PaulMNUSA University of Minnesota Mid-Central Research and Outreach CenterWillmarMNUSA Science Innovations WillmarMNUSA

Background:Microbiota development is a critical aspect of turkey poult maturation,and the succession of microbes in the turkey gut has been shown to correlate with poult performance.The purpose of this study was to determine the fate of the microbiota in turkey poults after movement of birds first raised in an isolated hatch brood system into a more traditional commercial brood facility with pre-existing birds.Turkey poults were first divided into groups raised in conventional brood pens from day-of-hatch and those raised in an experimental hatch brood system.After 11 days of growth,hatch brood birds were moved into pens within the conventional brood barn and monitored for an additional 18 days.Sampling of both hatch brood and conventional pen birds was performed at multiple timepoints throughout the study,and cecal content was used to analyze the bacterial microbiota using 16S rRNA gene amplicon sequencing.Results:Alpha diversity tended to be higher in samples from conventional pen birds compared to those from hatch brood birds prior to the day 11 move,but the difference between systems was not observed post-move.Using beta diversity metrics,bacterial community succession appeared delayed in the hatch brood system birds pre-move,but post-move community composition quickly converged with that of the conventional pen birds.This was validated through assessment of significantly different genera between hatch brood system and conventional pen birds,where numbers of significantly different taxa quickly decreased following the move.Some key taxa previously associated with poult performance were delayed in their appearance and relative abundance in hatch brood birds.Conclusions:Overall,this study demonstrates that the use of isolated hatch brood systems has an impact on the poult gut microbiota,but its impact is resolved quickly once the birds are introduced into a conventional brood environment.Therefore,the benefits of pathogen reduction with hatch brood systems may outweigh negative microbiota impacts due to isolati

关键词： Brood Gut Hatch Microbiota Poult Succession Turkey

Integrins and their potential roles in mammalian pregnancy

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journal of Animal Science and Biotechnology 2024年第1期15卷 1-19页

作者： Gregory A.johnson Robert C.Burghardt Fuller W.Bazer Heewon Seo joe W.Cain Department of Veterinary Integrative Biosciences School of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege StationTX 77843‑4459USA Department of Animal Science College of Agriculture and Life SciencesTexas A&M UniversityCollege StationTX 77843‑2471USA

Integrins are a highly complex family of receptors that, when expressed on the surface of cells, can mediate reciprocal cell-to-cell and cell-to-extracellular matrix(ECM) interactions leading to assembly of integrin adhesion complexes(IACs) that initiate many signaling functions both at the membrane and deeper within the cytoplasm to coordinate processes including cell adhesion, migration, proliferation, survival, differentiation, and metabolism. All metazoan organisms possess integrins, and it is generally agreed that integrins were associated with the evolution of multicellularity, being essential for the association of cells with their neighbors and surroundings, during embryonic development and many aspects of cellular and molecular biology. Integrins have important roles in many aspects of embryonic development, normal physiology, and disease processes with a multitude of functions discovered and elucidated for integrins that directly influence many areas of biology and medicine, including mammalian pregnancy, in particular implantation of the blastocyst to the uterine wall, subsequent placentation and conceptus(embryo/fetus and associated placental membranes) development. This review provides a succinct overview of integrin structure, ligand binding, and signaling followed with a concise overview of embryonic development, implantation, and early placentation in pigs, sheep, humans, and mice as an example for rodents. A brief timeline of the initial localization of integrin subunits to the uterine luminal epithelium(LE) and conceptus trophoblast is then presented, followed by sequential summaries of integrin expression and function during gestation in pigs, sheep, humans, and rodents. As appropriate for this journal, summaries of integrin expression and function during gestation in pigs and sheep are in depth, whereas summaries for humans and rodents are brief. Because similar models to those illustrated in Fig. 1, 2, 3, 4, 5 and 6 are present throughout the scientific literature, the illustrations in this m

关键词： Humans Implantation Integrins Pigs Pregnancy Rodents Sheep

Rescue from complications after pancreaticoduodenectomies at a low-volume Caribbean center:Value of tailored peri-pancreatectomy protocols

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World journal of Gastrointestinal Surgery 2024年第3期16卷 681-688页

作者： Shamir O Cawich Elijah Dixon Parul j Shukla Shailesh V Shrikhande Rahul R Deshpande Fawwaz Mohammed Neil W Pearce Wesley Francis Shaneeta johnson johann Bujhawan Department of Surgery University of the West IndiesSt Augustine 000000Trinidad and Tobago Department of Surgery Faculty of MedicineUniversity of CalgaryCalgaryAlberta T2N2T9Canada Department of Surgery Weill Cornell Medical CollegeNew YorkNY 10065United States Department of Surgical Oncology Tata Memorial CenterHomi Bhabha National UniversityMumbai 400012India Department of Surgery Manchester Royal InfirmaryManchester M139WLUnited Kingdom University Surgical Unit Southampton General HospitalSouthampton SO166YDUnited Kingdom Department of Surgery University of the West IndiesNassau N-1184Bahamas Department of Surgery Morehouse School of MedicineAtlantaGA 30310United States Department of Surgery General Hospital in Port of SpainPort of Spain 000000Trinidad and Tobago

BACKGROUND Pancreaticoduodenectomy(PD)is a technically complex operation,with a re-latively high risk for complications.The ability to rescue patients from post-PD complications is as a recognized quality measure.Tailored protocols were instituted at our low volume facility in the year 2013.AIM To document the rate of rescue from post-PD complications with tailored protocols in place as a measure of quality.METHODS A retrospective audit was performed to collect data from patients who experienced major post-PD complications at a low volume pancreatic surgery unit in Trinidad and Tobago between january 1,2013 and june 30,2023.Stan-dardized definitions from the International Study Group of Pancreatic Surgery were used to define post-PD complications,and the modified Clavien-Dindo classification was used to classify post-PD complications.RESULTS Over the study period,113 patients at a mean age of 57.5 years(standard deviation[SD]±9.23;range:30-90;median:56)underwent PDs at this facility.Major complications were recorded in 33(29.2%)patients at a mean age of 53.8 years(SD:±7.9).Twenty-nine(87.9%)patients who experienced major morbidity were salvaged after aggre-ssive treatment of their complication.Four(3.5%)died from bleeding pseudoaneurysm(1),septic shock secondary to a bile leak(1),anastomotic leak(1),and myocardial infarction(1).There was a significantly greater salvage rate in patients with American Society of Anesthesiologists scores≤2(93.3%vs 25%;P=0.0024).CONCLUSION This paper adds to the growing body of evidence that volume alone should not be used as a marker of quality for patients requiring PD.Despite low volumes at our facility,we demonstrated that 87.9%of patients were rescued from major complications.We attributed this to several factors including development of rescue protocols,the competence of the pancreatic surgery teams and continuous,and adaptive learning by the entire institution,cul-minating in the development of tailored peri-pancreatectomy protocols.

关键词： Pancreas Complication Rescue Failure Morbidity Mortality Pancreaticoduodenectomy

Australian children living with rare diseases:health service use and barriers to accessing care

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World journal of Pediatrics 2023年第7期19卷 701-709页

作者： Suzy Teutsch Yvonne Zurynski Guy DEslick Marie Deverell john Christodoulou Helen Leonard Troy Dalkeith Sandra Ljjohnson Elizabeth jElliott Faculty of Medicine and Health Discipline of Child and Adolescent HealthThe University of SydneySydneyNSWAustraliaAustralian Australian Paediatric Surveillance Unit Kids ResearchSydney Children's Hospitals NetworkWestmeadNSWAustralia Australian Institute of Health Innovation Center for Healthcare Resilience and Implementation Scienceand NHMRC Partnership Centre in Health System SustainabilityMacquarie UniversitySydneyNSWAustraliaFaculty of Medicine and HealthDiscipline of Child and Adolescent HealthThe University of SydneySydneyNSWAustralia Government Department of Health Western Australia PerthWAAustralia Murdoch Children's Research Institute and Victorian Clinical Genetics Services Royal Children's HospitalParkvilleVICAustralia Department of Paediatrics The University of MelbourneParkvilleVICAustralia Telethon Kids Institute The University of Western AustraliaNedlandsWAAustralia Genetic Metabolic Disorders Service Sydney Children's Hospitals NetworkWestmeadNSWAustralia

Background Children with rare diseases experience challenges at home and school and frequently require multi-disciplinary healthcare.We aimed to determine health service utilization by Australian children with rare diseases and barriers to access-ing healthcare.Methods Parents completed an online survey on health professional and emergency department(ED)presentations,hospi-talization,and barriers to accessing services.Potential barriers to service access included residential location(city,regional,remote)and child health-related functioning,determined using a validated,parent-completed measure-of-function tool.Results Parents of 462 children with over 240 rare diseases completed the survey.Compared with the general population,these children were more likely to be hospitalized[odds ratio(OR)=17.25,95%confidence interval(CI)=15.50-19.20]and present to the ED(OR=4.15,95%CI=3.68-4.68)or a family physician(OR=4.14,95%CI=3.72-4.60).Child functional impairment was nil/mild(31%),moderate(48%)or severe(22%).Compared to children with nil/mild impair-ment,those with severe impairment were more likely to be hospitalized(OR=13.39,95%CI=7.65-23.44)and present to the ED(OR=11.16,95%CI=6.46-19.27).Most children(75%)lived in major cities,but children from regional(OR=2.78,95%CI=1.72-4.55)and remote areas(OR=9.09,95%CI=3.03-25.00)experienced significantly more barriers to healthcare access than children from major cities.Barriers included distance to travel,out-of-pocket costs,and lack of specialist medical and other health services.Conclusions Children with rare diseases,especially those with severe functional impairment have an enormous impact on health services,and better integrated multidisciplinary services with patient-centered care are needed.Access must be improved for children living in rural and remote settings.

关键词： Access Health functioning Health service use Rare diseases