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Pollinators exert positive selection on flower size on urban,but not on rural Scotch broom(Cytisus scoparius ***)

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Journal of Plant Ecology 2018年第3期11卷 493-501页

作者： robert frederick bode Rebecca Tong Department of Natural Sciences Saint Martin’s University405 Old Main5000 Abbey WayLaceyWA 98503USA

Aims Adaptive evolution of invasive species is both particularly exciting for the evolutionary biologist and worrisome for those interested in controlling or halting *** species often have a dis-tinct timeline and well-recorded population *** invaders encounter new environments,they undergo rapid adaptive *** aim in this study was to measure variation of floral size in the invasive shrub Cytisus scoparius(Scotch broom)and measure natural selection by pollinators on that *** research has found that this invasive plant is pollinator limited in Washington State and that declines in pollinator populations can contribute to local extinction in another invaded range(New Zealand).This plant is pollinated by both native and introduced species of bees,represent-ing a broad range of pollinator *** scoparius has a flower structure that is highly conducive to studies on pollinator choice,even in the absence of direct pollinator *** We surveyed urban and rural sites in and around the city of Olympia in Washington *** banner width,we were able to show that flower size varies substantially between plants but mini-mally within *** measuring the proportion of flowers that were‘tripped’,we could determine pollinator visitation rates and thus determine the level of selection due to pollinator choice *** Findings We found that *** is under natural selection by pollinators for increased flower ***,such positive natural selection was only seen in urban populations although it was consistent across two flowering *** populations of Scotch broom do not appear to be under selection on flower *** natural selection by pollinators on broom flowers could result in adaptive evolution into a new pollination niche by an invading species.A higher level of variation in broom flowers seen here than seen in previous works in native regions suggests that *** may be high

关键词： invasive evolution pollinator selection flower

Do tensile and shear forces exerted on cells influence mechanotransduction through stored energy considerations?

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BIOCELL 2024年第4期48卷 525-540页

作者： frederick H.SILVER TANMAY DESHMUKH Department of Pathology and Laboratory Medicine Robert Wood Johnson Medical SchoolRutgersThe State University of New JerseyPiscatawayNJ 08854USA OptoVibronex LLC.Ben Franklin Tech PartnersBethlehemPA 18015USA

All tissues in the body are subjected externally to gravity and internally by collagenﬁbril and cellular retractive forces that create stress and energy equilibrium required for *** involves mechanical work(force through a distance)and energy storage as kinetic and potential *** leads to changes in cell mitosis or apoptosis and the synthesis or loss of tissue *** involves the application of energy directly to cells through integrin-mediated processes,cell-cell connections,stretching of the cell cytoplasm,and activation of the cell nucleus via yes-associated protein(YAP)and transcriptional coactivator with PDZ-motif(TAZ).These processes involve numerous complexes,intermediate molecules,and multiple *** pathways have been identiﬁed from research studies on vertebrate cell culture and from studies in *** pathways involve mechanosensors and other molecules that activate the *** review discusses the mitogen-activated protein kinase(MAPK)family,Hippo,Hedgehog,and Wingless-related integration site(WNT)/βcatenin signaling *** mediators covered includeβcatenin,ion channels,growth factors,hormone receptors,members of the Ras superfamily,and components of the linker of nucleoskeleton and cytoskeleton(LINC)***,the interrelationship among the different pathways remains to be clariﬁ***-mediated mechanotransduction involves direct tensile loading and energy applied to the cell membrane via collagenﬁbril *** energy is transferred between cells by stretching the cell-cell connections involving cadherins and the WNT/βcatenin *** alterations induce changes in intracellular events in the cytoskeleton and nuclear skeleton caused by the release of YAP and *** coactivators then penetrate through the nuclear pores and inﬂuence nuclear cell *** in the balance of forces and energy applied to cells and tissues is hypothesized to shift th

关键词： MAPK family Hippo Hedgehog WNT pathway βcatenin Ion channels Growth factor receptors Hormone receptors Ras superfamily LINC complex Collagen Cadherins

Serelaxin increases the antifibrotic action of rosiglitazone in a model of hepatic fibrosis

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World Journal of Gastroenterology 2017年第22期23卷 3999-4006页

作者： robert G Bennett Ronda L Simpson frederick G Hamel Research Service Nebraska-Western Iowa Health Care System Department of Internal Medicine University of Nebraska Medical Center

To determine the effect of combined serelaxin and rosiglitazone treatment on established hepatic *** fibrosis was induced in mice by carbon tetrachloride administration for 6 wk, or vehicle alone (nonfibrotic mice). For the final 2 wk, mice were treated with rosiglitazone, serelaxin, or both rosiglitazone and serelaxin. Serum liver enzymes and relaxin levels were determined by standard methods. The degree of liver collagen content was determined by histology and immunohistochemistry. Expression of type I collagen was determined by quantitative PCR. Activation of hepatic stellate cells was assessed by alpha-smooth muscle actin (SMA) levels. Liver peroxisome proliferator activated receptor-gamma coactivator 1 alpha (PGC1α) was determined by Western *** of mice with CCl4 resulted in hepatic fibrosis as evidenced by increased liver enzyme levels (ALT and AST), and increased liver collagen and SMA. Monotherapy with either serelaxin or rosiglitazone for 2 wk was generally without effect. In contrast, the combination of serelaxin and rosiglitazone resulted in significantly improved ALT levels (P < 0.05). Total liver collagen content as determined by Sirius red staining revealed that only combination treatment was effective in reducing total liver collagen (P < 0.05). These results were supported by immunohistochemistry for type I collagen, in which only combination treatment reduced fibrillar collagen levels (P < 0.05). The level of hepatic stellate cell activation was modestly, but significantly, reduced by serelaxin treatment alone, but combination treatment resulted in significantly lower SMA levels. Finally, while hepatic fibrosis reduced liver PGC1α levels, the combination of serelaxin and rosiglitazone resulted in restoration of PGC1α protein *** combination of serelaxin and rosiglitazone treatment for 2 wk was effective in significantly reducing established hepatic fibrosis, providing a potential

关键词： Relaxin Peroxisome proliferator-activated receptors Liver cirrhosis Liver diseases Fibrosis

Uncovering the Online Social Structure Surrounding COVID-19

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Journal of Social Computing 2021年第2期2卷 157-165页

作者： Philip D.Waggoner robert Y.Shapiro Samuel frederick Ming Gong Institute for Social and Economic Research and Policy Columbia UniversityNew York CityNY 10027USA Department of Political Science Columbia UniversityNew York CityNY 10027USA. Department of Quantitative Methods in the Social Sciences Columbia UniversityNew York CityNY 10027USA

How do people talk about COVID-19 online?To address this question,we offer an unsupervised framework that allows us to examine Twitter framings of the *** approach employs a network-based exploration of social media data to identify,categorize,and understand communication patterns about the novel coronavirus on *** simplest structure that emerges from our analysis is the distinction between the internal/personal,external/global,and generic threat framings of the *** structure replicates in different Twitter samples and is validated using the variation of information measure,reflecting the significance and stability of our *** an exploratory study is useful for understanding the contours of the natural,non-random structure in this online *** contend that this understanding of structure is necessary to address a host of causal,supervised,and related questions downstream.

关键词： COVID-19 networks community detection twitter exploratory data analysis

A retrospective analysis of gender among patients admitted to a clinical decision unit at risk for acute coronary syndrome

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World Journal of Emergency Medicine 2023年第2期14卷 133-137页

作者： Joby Thoppil Lauren Kraut Collin Montgomery Wilfrido Castillo robert Silverman Sanjey Gupta frederick Davis Department of Emergency Medicine University of Texas Southwestern Medical CenterTexas 75002USA Department of Emergency Medicine Long Island Jewish Medical CenterQueens NY 11040USA Department of Emergency Medicine South Shore HospitalBay Shore NY 11706USA

INTRODUCTION Chest pain is a common chief complaint and encompasses nearly 5.2% of all patients seen in emergency departments(ED). In the United States, this accounts for approximately six million annual visits.[1-4]The evaluation of patients with chest pain in the ED is a time-consuming and challenging process because the physician must identify those with life-threatening cardiac chest pain, while avoiding unnecessary and costly evaluations of those with non-cardiac chest pain.

关键词： admitted consuming patients

Mechanotransduction-The relationship between gravity,cells and tensile loading in extracellular matrix

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BIOCELL 2022年第2期46卷 297-299页

作者： frederick H.SILVER Department of Pathology and Laboratory Medicine Robert Wood Johnson Medical SchoolRutgersThe State University of New JerseyPiscataway08854USA

Gravity plays a central role in vertebrate development and *** involves the tensile tethering of veins and arteries,connections between the epidermis and dermis in skin,tensile stress concentrations that occur at tissue interfaces,cell-cell interactions,cell-collagen fiber stress transfer in extracellular matrix and fluid shear *** attention in the past has been directed at understanding the myriad of biochemical players associated with mechanotransduction pathways,less attention has been focused on determining the tensile mechanical behavior of tissues in *** sit on the surface of collagen fibers in living skin and exert a retractile force on the *** retractile force pulls against the tension in collagen fibers in *** fibroblast-collagen fiber interactions are altered either by changes in fibroblast adhesion or after formation of cancer associated fibroblasts,and changes in cell junctions,alterations in the retractive force leads to changes in *** purpose of this paper is to present a model of tensile forces that occur at the fibroblast-collagen fiber interface and how these forces are important in extracellular matrix physiology in health and disease.

关键词： Collagen Mechanotransduction Fibroblasts Gravity Tensile forces

Forest Wetland Area and the Forest Sector Economy in the U.S. South

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Open Journal of Forestry 2018年第3期8卷 409-428页

作者： frederick Cubbage robert Abt Ray Sheffield Curt Flather James Wickham North Carolina State University Raleigh North Carolina USA Consultant Asheville North Carolina USA USDA Forest Service Fort Collins Colorado USA U.S Environmental Protection Agency Research Triangle Park North Carolina USA

This article reviews current data on forest wetlands and their economic contributions in the South, ranging from Texas to Virginia. Based on USDA Forest Service Forest Inventory and Analysis (FIA) data, the wetland category comprised 17.7% of timber land area on all private and public lands in the South. This included 4.25 million ha of hydric sites;0.77 million ha mesic wet;9.55 million ha mesic, with only seasonal access;for a total of 14.57 million ha. The Natural Resource Inventory (NRI) for 2012 on private lands estimated that there were 14.71 million ha forested wetlands, which comprised 17.7% of all forested private forest area. The 2015 National Land Cover Data for the South estimated that there were 17.8 million ha of woody wetlands, which comprised 8% to 12% of the southern land area, and there were also 4.45 million ha of emergent herbaceous sites. About 10% of the southern timber forest sector would be based on harvests from wetland forests economy ($455 million per year), while the 17.7% of wetland land area would provide a proportional share of the annual nontimber forest products ($44 million) and payments for ecosystem services ($134 million). Wetlands also provide important nontimber forest products, and ecosystem services, which are beginning to develop active private and public markets.

关键词： Forest Wetlands Area Economics Valuation

Pasture-finishing of bison improves animal metabolic health and potential health-promoting compounds in meat

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Journal of Animal Science and Biotechnology 2023年第4期14卷 1759-1776页

作者： Stephan van Vliet Amanda D.Blair Lydia M.Hite Jennifer Cloward robert E.Ward Carter Kruse Herman A.van Wietmarchsen Nick van Eekeren Scott L.Kronberg frederick D.Provenza Center for Human Nutrition Studies Department of NutritionDieteticsand Food SciencesCollege of Agriculture and Applied SciencesUtah State UniversityLoganUT 84322USA Department of Wildland Resources Utah State UniversityLoganUT 84332USA Department of Animal Science South Dakota State UniversityBrookingsSD 57707USA Turner Institute of Ecoagriculture BozemanMT 59718USA Louis Bolk Institute Bunnik 3981AJthe Netherlands Northern Great Plains Research Laboratory USDA-Agricultural Research ServiceMandanND 58554USA

Background With rising concerns regarding the effects of red meat on human and environmental health,a growing number of livestock producers are exploring ways to improve production systems.A promising avenue includes agro-ecological practices such as rotational grazing of locally adapted ***,growing consumer interest in pasture-finished meat(i.e.,grass-fed)has raised questions about its nutritional ***,the goal of this study was to determine the impact of two common finishing systems in North American bison—pasture-finished or pen-finished on concentrates for 146 d—on metabolomic,lipidomic,and fatty acid profiles of striploins(*** lumborum).Results Six hundred and seventy-one(671)out of 1570 profiled compounds(43%)differed between pasture-and penfinished conditions(n=20 animals per group)(all,P<0.05).Relative to pasture-finished animals,the muscle of pen-finished animals displayed elevated glucose metabolites(~1.6-fold),triglycerides(~2-fold),markers of oxidative stress(~1.5-fold),and proteolysis(~1.2-fold).In contrast,pasture-finished animals displayed improved mitochondrial(~1.3-fold higher levels of various Krebs cycle metabolites)and carnitine metabolism(~3-fold higher levels of long-chain acyl carnitines)(all P<0.05).Pasture-finishing also concentrated higher levels of phenolics(~2.3-fold),alpha-tocopherol(~5.8-fold),carotene(~2.0-fold),and very long-chain fatty acids(~1.3-fold)in their meat,while having lower levels of a common advanced lipoxidation(4-hydroxy-nonenal-glutathione;~2-fold)and glycation end-product(N6-carboxymethyllysine;~1.7-fold)(all P<0.05).In contrast,vitamins B5,B6,and C,gamma/beta-tocopherol,and three phenolics commonly found in alfalfa were~2.5-fold higher in pen-finished animals(all P<0.05);suggesting some concentrate feeding,or grazing plants rich in those compounds,may be *** Pasture-finishing(i.e.,grass-fed)broadly improves bison metabolic health and accumulates additional po

关键词： Bison Grass-fed Meat Nutrition Omega-3 fats Pasture-raised Phytochemicals

ECONOMIC DECISION SUPPORT SYSTEM FOR LOW COST COMMUNITY WATER SUPPLY TECHNOLOGY SELECTION

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ECONOMIC DECISION SUPPORT SYSTEM FOR LOW COST COMMUNITY WATE...