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Dendroclimatic analysis of white pine (Pinus strobus L.)using long-term provenance test sites across eastern North America

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Forest Ecosystems 2018年第3期5卷 221-235页

作者： Sophan chhin Ronald S.Zalesny Jr William c.Parker john Brissette Division of Forestry and Natural Resources West Virginia University322 Percival HallPO Box 6125MorgantownWV26506USA USDA Forest Service Northern Research Station5985Highway KRhinelanderWI 54501USA Ontario Forest Research Institute 1235Queen St.ESault Ste.MarieON P6A 2E5Canada USDA Forest Service Northern Research Station271Mast RoadDurhamNH 03824USA

Background: The main objective of this study was to examine the climatic sensitivity of the radial growth response of 13 eastern white pine(Pinus strobus L.) provenances planted at seven test sites throughout the northern part of the species’ native distribution in eastern North ***: The test sites(i.e., Wabeno, Wisconsin, USA; Manistique, Michigan, USA; Pine River, Michigan, USA; Newaygo,Michigan, USA; Turkey Point, Ontario, canada; Ganaraska, Ontario, canada; and Orono, Maine, USA) examined in this study were part of a range-wide white pine provenance trial established in the early 1960 s in the eastern United States and canada. Principal components analysis(PcA) was used to examine the main modes of variation [first(Pc1) and second(Pc2) principal component axes] in the standardized radial growth indices of the provenances at each test *** year scores for Pc1 and Pc2 were examined in relation to an array of test site climate variables using multiple regression analysis to examine the commonality of growth response across all provenances to the climate of each test site. Provenance loadings on Pc1 and Pc2 were correlated with geographic parameters(i.e., latitude, longitude,elevation) and a suite of biophysical parameters associated with provenance origin ***: The amount of variation in radial growth explained by Pc1 and Pc2 ranged from 43.4% to 89.6%. Dendroclimatic models revealed that white pine radial growth responses to climate were complex and differed among sites. The key dendroclimatic relationships observed included sensitivity to high temperature in winter and summer, cold temperature in the spring and fal(i.e., beginning and end of the growing season), summer moisture stress, potential sensitivity to storminduced damage in spring and fal, and both positive and negative effects of higher winter snowfal. Separation of the loadings of provenances on principal component axes was mainly associated with temperature-related bioclima

关键词： Adaptation climate change Dendrochronology Seed source

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A feeder-free,human plasma-derived hydrogel for maintenance of a human embryonic stem cell phenotype in vitro

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cell Regeneration 2012年第1期1卷 38-46页

作者： Fiona c Lewis Nicholas Bryan john A Hunt clinical Engineering UKCTEInstitute of Ageing and Chronic DiseaseUniversity of LiverpoolLiverpool L693GAUK

Background:Human embryonic stem cells(hEScs)represent a tremendous resource for cell therapies and the study of human development;however to maintain their undifferentiated state in vitro they routinely require the use of mouse embryonic fibroblast(MEF)feeder-layers and exogenous protein media ***:These well established requirements can be overcome and in this study,it will be demonstrated that phenotypic stability of hEScs can be maintained using a novel,human plasma protein-based hydrogel as an extracellular culture matrix without the use of feeder cell *** were resuspended in human platelet poor plasma(PPP),which was gelled by the addition of calcium containing DMEM-based hESc culture *** and genomic expression of the pluripotency markers OcT4,NANOG and SOX2 were measured using immunohistochemistry and qRT-PcR *** hESc morphology was demonstrated throughout in vitro culture and both viability and phenotypic stability were maintained throughout extended culture,up to 25 ***:PPP-derived hydrogel has demonstrated to be an efficacious alternative to MEF co-culture with its hydrophilicity allowing for this substrate to be delivered via minimally invasive procedures in a liquid phase with polymerization ensuing in *** this provides a novel technique for the study of this unique group of stem cells in either 2D or 3D both in vitro and in vivo.

关键词： Embryonic stem cells Hydrogel Pluripotent stem cells cell culture

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Iron:An emerging factor in colorectal carcinogenesis

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World Journal of Gastroenterology 2010年第6期16卷 663-672页

作者： Anita cG chua Borut Klopcic Ian c Lawrance john K Olynyk Debbie Trinder Debbie Trinder School of Medicine and PharmacologyThe University of Western AustraliaFremantle Hospital Western Australian Institute for Medical Research Fremantle Hospital The centre for Inflammatory Bowel Diseases Fremantle Hospital

The carcinogenic potential of iron in colorectal cancer(cRc) is not fully *** is able to undergo reduction and oxidation,making it important in many physiological *** inherent redox property of iron,however,also renders it toxic when it is present in ***-mediated generation of reactive oxygen species via the Fenton reaction,if uncontrolled,may lead to cell damage as a result of lipid peroxidation and oxidative DNA and protein *** may promote carcinogenesis through increased genomic instability,chromosomal rearrangements as well as mutations of proto-oncogenes and tumour suppressor genes. carcinogenesis is also affected by inflammation which is exacerbated by *** studies indicate an association between high dietary iron intake and cRc *** this editorial,we examine the link betweeniron-induced oxidative stress and inflammation on the pathogenesis of cRc.

关键词： Iron Haem colorectal cancer Oxidative stress Inflammation Haemochromatosis

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In vitro expression and analysis of the 826 human G protein-coupled receptors

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Protein & cell 2016年第5期7卷 325-337页

作者： Xuechen Lv Junlin Liu Qiaoyun Shi Qiwen Tan Dong Wu john J. Skinner Angela L. walker Lixia Zhao Xiangxiang Gu Na chen Lu Xue Pei Si Lu Zhang Zeshi Wang Vsevolod Katritch Zhijie Liu Raymond c. Stevens iHuman Institute ShanghaiTech University Shanghai 201210 China Department of Biological Sciences Bridge Institute University of Southern California Los Angeles CA 90089 USA

G protein-coupled receptors （GPcRs） are involved in all human physiological systems where they are responsible for transducing extracellular signals into cells. GPcRs signal in response to a diverse array of stimuli including light, hormones, and lipids, where these signals affect downstream cascades to impact both health and disease states. Yet, despite their importance as therapeutic tar- gets, detailed molecular structures of only 30 GPcRs have been determined to date. A key challenge to their structure determination is adequate protein expression. Here we report the quantification of protein expression in an insect cell expression system for all 826 human GPcRs using two different fusion constructs. Expression char- acteristics are analyzed in aggregate and among each of the five distinct subfamilies. These data can be used to identify trends related to GPcR expression between dif- ferent fusion constructs and between different GPcR families, and to prioritize lead candidates for future structure determination feasibility.

关键词： G protein-coupled receptors insect,protein expression surface expression analysis fusionconstruct

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Therapeutic implications of advanced age at time of spinal cord injury

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Neural Regeneration Research 2019年第11期14卷 1895-1896页

作者： Andrew N. Stewart john c. Gensel Bei Zhang Spinal cord and Brain Injury Research center Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKYUSA college of Public Health Shaanxi University of Chinese MedicineXianyangShaanxi ProvinceChina

A recent demographic shift towards increased age at time of spinal cord injury (ScI), as well as decreased functional recovery following ScI in older populations, create the need to investigate how age effects ScI pathology and repair (Scivoletto et al., 2003). While decreased neuroplasticity or physical strength with age may contribute to functional deficits, work from our lab and others have identified exacerbated acute inflammatory events as contributors to age-dependent secondary injury. Specifically, our recent paper identified that increased production of reactive oxygen species (ROS) from macrophage nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) with age exacerbates secondary injury after ScI (Zhang et al., 2019).

关键词： spinal cord injury nicotinamide adenine dinucleotide phosphate(NADPH) reactive oxygen species(ROS)

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Retrospective analysis of eFAST ultrasounds performed on trauma activations at an academic level-1 trauma center

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World Journal of Emergency Medicine 2020年第1期11卷 12-17页

作者： Samantha Shwe Lauren Witchey Shadi Lahham Ethan Kunstadt Inna Shniter john c.Fox School of Medicine University of CaliforniaIrvine 92697USA Department of Emergency Medicine University of CaliforniaIrvineOrangeCA 92868USA

BAcKGROUND:Point-of-care ultrasound(POcUS)has become increasingly integrated into the practice of emergency medicine.A common application is the extended focused assessment with sonography in trauma(eFAST)*** American college of Emergency Physicians has guidelines regarding the scope of ultrasound in the emergency department and the appropriate *** objective of this study was to conduct a review of performed,documented and billed eFAST ultrasounds on trauma activation ***:This was a retrospective review of all trauma activation patients during a 10-month period at an academic level-one trauma center.A list comparing all trauma activations was crossreferenced with a list of all billed eFAST *** records were reviewed to determine whether an eFAST was indicated,performed,and appropriately ***:We found that 1,507 of 1,597 trauma patients had indications for eFAST,but 396(27%)of these patients did not have a billed *** these 396 patients,87(22%)had documentation in the provider note that an eFAST was performed but there was no separate procedure *** remaining 309(78%)did not have any documentation of the eFAST in the patient’s chart although an eFAST was recorded and reviewed during ultrasound quality ***:A significant proportion of trauma patients had eFAST exams performed but were not documented or *** of documentation was *** ultrasound programs require appropriate reimbursement to support training,credentialing,equipment,quality assurance,and device *** study demonstrates a significant absence of adequate documentation leading to potential revenue loss for an emergency ultrasound program.

关键词： Point-of-care ultrasound Emergency medicine Focused assessment withsonography in trauma Trauma activation Blunt trauma

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Mapping landslide susceptibility at the Three Gorges Reservoir, china, using gradient boosting decision tree,random forest and information value models

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Journal of Mountain Science 2020年第3期17卷 670-685页

作者： cHEN Tao ZHU Li NIU Rui-qing TRINDER c john PENG Ling LEI Tao Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Geomatics Technology and Application key Laboratory of Qinghai Province Xining 810001China School of civil and Environmental Engineering The University of New South WalesSydneyNSW 2052Australia china Institute of Geo-Environment Monitoring Beijing 100081China School of Electronical and Information Engineering Shaanxi University of Science and TechnologyXi’an 710021China

This work was to generate landslide susceptibility maps for the Three Gorges Reservoir(TGR) area, china by using different machine learning models. Three advanced machine learning methods, namely, gradient boosting decision tree(GBDT), random forest(RF) and information value(InV) models, were used, and the performances were assessed and compared. In total, 202 landslides were mapped by using a series of field surveys, aerial photographs, and reviews of historical and bibliographical data. Nine causative factors were then considered in landslide susceptibility map generation by using the GBDT, RF and InV models. All of the maps of the causative factors were resampled to a resolution of 28.5 m. Of the 486289 pixels in the area,28526 pixels were landslide pixels, and 457763 pixels were non-landslide pixels. Finally, landslide susceptibility maps were generated by using the three machine learning models, and their performances were assessed through receiver operating characteristic(ROc) curves, the sensitivity, specificity,overall accuracy(OA), and kappa coefficient(KAPPA). The results showed that the GBDT, RF and In V models in overall produced reasonable accurate landslide susceptibility maps. Among these three methods, the GBDT method outperforms the other two machine learning methods, which can provide strong technical support for producing landslide susceptibility maps in TGR.

关键词： Mapping landslide susceptibility Gradient boosting decision tree Random forest Information value model Three Gorges Reservoir

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Lights at night:does photobiomodulation improve sleep?

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Neural Regeneration Research 2023年第3期18卷 474-477页

作者： Audrey Valverde catherine Hamilton cécile Moro Malvina Billeres Pierre Magistretti john Mitrofanis UniversitéGrenoble Alpes FDD and CEA-LETIClinatecGrenobleFrance WellRed Inc LauncestonTasmaniaAustralia King Abdullah University of Science and Technology Thuwal Saudi Arabia Institute of Ophthalmology University College LondonLondonUK

Sleep is a critical part of our daily *** impacts every organ and system of our body,from the brain to the heart and from cellular metabolism to immune function.A consistent daily schedule of quality of sleep makes a world of difference to our health and *** its importance,so many individuals have trouble sleeping *** quality sleep has such a detrimental impact on many aspects of our lives;it affects our thinking,learning,memory,and ***,and most poignantly,poor quality sleep over time increases the risk of developing a serious medical condition,including neurodegenerative *** this review,we focus on a potentially new non-pharmacological treatment that improves the quality of *** treatment,called photobiomodulation,involves the application of very specific wavelengths of light to body *** animal models,these wavelengths,when applied at night,have been reported to stimulate the removal of fluid and toxic waste-products from the brain;that is,they improve the brain’s inbuilt house-keeping *** suggest that transcranial nocturnal photobiomodulation,by improving brain function at night,will help improve the health and well-being of many individuals,by enhancing the quality of their sleep.

关键词： aquaporin 4 glymphhatic infrared non-pharmacological red sleep cap transcranial wakefulness

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conditional coherent risk measures and regime-switching conic pricing

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Probability, Uncertainty and Quantitative Risk 2021年第4期6卷 267-300页

作者： Engel john c Dela Vega Robert J Elliott UniSA Business University of South AustraliaSA 5000 AdelaideAustralia Haskayne School of Business University of CalgaryCalgaryAlbertaT2N 1N4Canada

This paper introduces and represents conditional coherent risk measures as essential suprema of conditional expectations over a convex set of probability measures and as distorted expectations given a concave distortion function.A model is then developed for the bid and ask prices of a European-type asset by a conic *** price process is governed by a modified geometric Brownian motion whose drift and diffusion coefficients depend on a Markov *** bid and ask prices of a European-type asset are then characterized using conic quantization.

关键词： conditional coherent risk measures Markov chains Regime-switching conic finance European options Distortion functions conic quantization

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Objects observed

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作者： john c. Stout.

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