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Quantifying the spatial and temporal distribution of tanglehead (Heteropogon contortus) on South texas rangelands

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Ecological Processes 2018年第1期7卷 14-22页

作者： Jose M.Mata Humberto L.Perotto-Baldivieso Fidel Hernández Eric D.Grahmann Sandra Rideout-Hanzak john t.Edwards Michael t.Page taylor M.Shedd Caesar Kleberg wildlife Research Institute Texas A&M University-Kingsville700 University Blvd.MSC 218KingsvilleTX 78363USA

Introduction:tanglehead is a grass native to southwestern US rangelands;however,its prevalence as a native invasive on South texas rangelands has increased rapidly during the last *** areas of monotypic stands have emerged in Jim Hogg,Duval,Brooks,and Kleberg *** aim of this research is to understand the spatial and temporal dynamics of these invasions as a model for the assessment of native invasive *** specific objectives were to(1)evaluate the feasibility of classifying tanglehead using 1-m resolution imagery data,(2)assess the spatial and temporal distribution of tanglehead in relation to soil type and distance from roads,and(3)quantify the temporal and spatial distribution of tanglehead on our study *** combined remote sensing approaches with landscape metrics to quantify the spatial and temporal distribution of tanglehead in five locations across our study *** calculated the normalized difference vegetation index and combined it with the original aerial imagery to conduct an unsupervised classification with the following land cover classes:woody vegetation,tanglehead,non-tanglehead herbaceous,and bare *** type and the distance from roads were assessed to determine the relationship between these factors and tanglehead spatial ***:we were able to successfully map tanglehead using the 1-m *** image classification approach resulted in accuracies greater than 85%for all *** occurred in sandy,loamy sand,and sandy loam *** 70% of tanglehead cover occurred within the first 150 m from the edge of *** cover increased from 7.1%(SE=1.1%)in 2008 to 17.8%(SE=5.4%)in *** established,small patches of tanglehead began aggregating or coalescing with existing stands,thereby creating larger patches over larger ***:Our study has shown the value of analyzing spatiotemporal dynamics of tanglehead with remote sensing techniques and landscape metrics to improve our unders

关键词： distribution landscape sandy

Looking back at the first twenty years of genomics

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Quantitative Biology 2022年第1期10卷 6-16页

作者： john Quackenbush Department of Biostatistics Harvard T.H.Chan School of Public HealthBostonMA 02115USA Channing Division of Network Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical SchoolBostonMA 02215USA Department of Data Science Dana-Farber Cancer InstituteBostonMA 02115USA

Earlier this year,we celebrated the twentieth anniversary of the publication of the first draft human genome sequence-or more correctly,the nearly simultaneous publication of draft versions of the public human genome ... 详细信息

关键词： draft anniversary celebrated

Human biofield therapy does not affect tumor size but modulates immune responses in a mouse model for breast cancer

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Journal of Integrative Medicine 2016年第5期14卷 389-399页

作者： Gloria Gronowicz Eric R.Secor Jr. john R.Flynn Liisa t.Kuhn Department of Surgery University of Connecticut Health Center Department of Immunology University of Connecticut Health Center Hartford Healthcare Hartford Hospital Department of Reconstructive Sciences University of Connecticut Health Center

OBJECtIVE： to assess the effect of human biofield therapy, an integrative medicine modality, on the development of tumors and metastasis, and immune function in a mouse breast cancer model. MEtHODS： Mice were injected with 66cl4 mammary carcinoma cells. In study one, mice received biofield therapy after cell injection. In study two, mice were treated by the biofield practitioner only prior to cell injection. Both studies had two control groups of mock biofield treatments and phosphate- buffered saline injection. Mice were weighed and tumor volume was determined. Blood samples were collected and 32 serum cytokine/chemokine markers were measured. Spleens/popliteal lymph nodes were isolated and dissociated for fluorescent-activated cell sorting （FACS） analysis of immune cells or metastasis assays in cell culture. RESULtS： No signifcant differences were found in weight, tumor size or metastasis. Significant effects were found in the immune responses in study one but no additional effects were found in study two. In study one, human biofield treatment significantly reduced percentage of CD4~CD441oCD25~ and percentage of CD8~ cells, elevated by cancer in the lymph nodes, to control levels determined by FACS analysis. In the spleen, only CD11b~ macrophages were increased with cancer, and human biofield therapy significantly reduced them. Of 11 cytokines elevated by cancer, only interferon-y, interleukin-1, monokine induced by interferon-y, interleukin-2 and macrophage inflammatory protein-2 were significantly reduced to control levels with human biofield therapy. CONCLUSION： Human biofield therapy had no significant effect on tumor size or metastasis but produced significant effects on immune responses apparent in the down-regulation of specific lymphocytes and serum cytokines in a mouse breast cancer model.

关键词： biological therapy breast cancer immune system integrative medicine cytokine energymedicine

Biomolecular hydration dynamics probed with 2D-IR spectroscopy:From dilute solution to a macromolecular crowd

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Chinese Chemical Letters 2015年第4期26卷 435-438页

作者： john t.King Evan J.Arthur Derek G.Osborne Charles L.Brooks Ⅲ Kevin J.Kubarych Department of Chemistry University of Michigan LSA Biophysics University of Michigan Department of Materials Science and Engineering University of Illinois

Although it is well known that water is essential for biological function, it has been a challenge to determine how water behaves near biomacromolecular interfaces, and what role water plays in influencing the dynamics of the biochemical machinery. By adopting a vibrational labeling strategy coupled with ultrafast two-dimensional infrared （2D-IR） spectroscopy, it has recently become possible to study hydration dynamics, site specifically at the surface of proteins and model membranes. we review our recent progress in measuring hydration dynamics in contexts ranging from small-molecule solutes to biomacromolecules in dilute, viscous, and crowded environments.

关键词： Protein hydration dynamicsMembrane dynamicsUltrafast infrared spectroscopy

“Subduction Initiation” for the Genesis of Podiform Chromite Deposits

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Acta Geologica Sinica(English Edition) 2015年第A2期89卷 122-123页

作者： ZHOU Meifu ROBINSON Paul t SU Benxun GAO Jianfeng LI Jianwei YANG Jingsui MALPAS john Department of Earth Sciences The University of Hong Kong Hong Kong China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of SciencesBeijng China

there is a diversity of unusual minerals and mineral inclusions associated with podiform chromitites. the presence of these minerals suggests that grains of arnphibolite （plagioclase, amphibole and zircon） and eclog... 详细信息

关键词： RESEARCH Subduction zones Amphibolites Basins (Geology) Subduction (Geology) Chromite

Adjuvant therapy in pancreatic cancer

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world Journal of Gastroenterology 2001年第4期7卷 482-489页

作者： Paula Ghaneh john Slavin Robert Sutton Mark Hartley john P Neoptolemos Department of Surgery.University of Liverpool 5~(th)Floor UCD Building.Daulby StreetLiverpool.L69 3GA.UK

the outlook for patients with pancreatic cancer has been grim. there have been major advances in the surgical treatment of pancreatic cancer, leading to a dramatic reduction in post-operative mortality from the development of high volume specialized centres. this stimulated the study of adjuvant and neoadjuvant treatments in pancreatic cancer including chemoradiotherapy and chemotherapy. Initial protocols have been based on the original but rather small GItSG study first reported in 1985. there have been two large European trials totalling over 600 patients (EORtC and ESPAC-1) that do not support the use of chemoradiation as adjuvant therapy. A second major finding from the ESPAC-1 trial (541 patients randomized) was some but not conclusive evidence for a survival benefit associated with chemotherapy. A third major finding from the ESPAC-1 trial was that the quality of life was not affected by the use of adjuvant treatments compared to surgery alone. the ESPAC-3 trial aims to assess the definitive use of adjuvant chemotherapy in a randomized controlled trial of 990 patients.

关键词： Pancreatic Neoplasms Antineoplastic Agents Combined Modality therapy Humans Research Support, Non-U.S. Gov't

Exsolved materials for CO_(2)reduction in high-temperature electrolysis cells

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Materials Reports(Energy) 2023年第2期3卷 62-81,I0003页

作者： Min Xu Ran Cao Han Qin Nuoxi Zhang wenle Yan Liming Liu john t.S.Irvine Di Chen the Future Laboratory Tsinghua UniversityBeijing100084China Academy of Arts&Design Tsinghua UniversityBeijing100084China weiyang College Tsinghua UniversityBeijing100084China School of Materials Science and Engineering Tsinghua UniversityBeijing100084China School of Chemistry University of St AndrewsSt AndrewsFifeKY169STUK

Electrochemical reduction of CO_(2)into valuable fuels and chemicals has become a contemporary research area,where the heterogeneous catalyst plays a critical *** nanoparticles supported on oxides performing as active sites of electrochemical reactions have been the focus of intensive ***,we review the CO_(2)reduction with active materials prepared by *** fundamental of exsolution was summarized in terms of mechanism and models,materials,and driven *** advances in the exsolved materials used in hightemperature CO_(2)electrolysis were catalogued into tailored interfaces,synergistic effects on alloy particles,phase transition,reversibility and electrochemical switching.

关键词： CO_(2)reduction Exsolution Solid oxide electrolysis cells Catalysts

Environmental landscape determinants of maximum forest canopy height of boreal forests

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Journal of Plant Ecology 2019年第1期12卷 96-102页

作者： Lingfeng Mao Christopher w.Bater john JStadt Barry white Piotr tompalski Nicholas C.Coops Scott E.Nielsen Department of Renewable Resources University of AlbertaEdmontonAlberta T6G 2H1Canada Forest Management Branch Forestry DivisionAlberta Agriculture and ForestryEdmontonAlberta T5K 2M4Canada Department of Forest Resource Management University of British ColumbiaVancouverBritish Columbia V6T 1Z4Canada

Aims Canopy height is a key driver of forest biodiversity and carbon *** estimates of canopy height are needed for assess-ing mechanisms relating to ecological patterns and processes of tree height *** global scales forest canopy height patterns are largely controlled by climate,while local variation at fine scales is due to differences in disturbance history and local patterns in envir-onmental *** relative effect of local environmental driv-ers on canopy height is poorly understood partly due to gaps in data on canopy height and methods for examining limiting ***,we used airborne laser scanning(ALS)data on vegetation structure of boreal forests to examine the effects of environmental factors on potential maximum forest canopy *** Relationships between maximum canopy height from ALS meas-ures and environmental variables were examined to assess factors limiting tree ***,we used quantile regression at the 0.90 quantile to relate maximum canopy height with environmental characteristics of climate(*** annual temperature[MAt]and mean annual precipitation),terrain(***)and depth-to-water(Dtw)across a 33000 km2 multiple use boreal forest landscape in northeast Alberta,*** Findings Maximum canopy height was positively associated with MAt,ter-rain slope and terrain-derived Dtw,collectively explaining 33.2%of the variation in *** strongest explanatory variable was Dtw explaining 26%of canopy height variation with peatland forests having naturally shorter maximum canopy heights,but also more sites currently at their maximum potential *** con-trast,the most productive forests(*** to xeric upland forests)had the fewest sites at their potential maximum height,illustrating the effects of long-term forest management,wildfires and general anthropogenic footprints on reducing the extent and abundance of older,taller forest habitat in Alberta’s boreal forest.

关键词： forest succession vegetation structure quantile regression remote sensing airborne laser scanning(ALS)

Connecting particle sphericity and circularity

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Particuology 2021年第1期19卷 1-4页

作者： john R.Grace Arian Ebneyamini Department of Chemical&Biological Engineering University of British ColumbiaVancouver V6T 1Z3Canada

Sphericity,a measure of how much a particle’s shape deviates from spherical,is useful as a shape factorwhen characterizing particulate ***,particle surface areas,required when determiningthe sphericity,are very difficult to *** a result,the circularity,derivable from microscopic views,is often measured instead and assumed to be equal to the *** paper shows that the twoquantities are generally not equal for simple non-spherical shapes and provides advice on improving theestimation of sphericity from circularity.

关键词： Non-spherical particles Sphericity Circularity Shape factorsa