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The Long-term Survival Chances of Young Massive Star Clusters

Chinese Journal of Astronomy and Astrophysics 2007年第2期7卷 155-186页

作者： richard de Grijs Geneviève Parmentier Department of Physics & Astronomy The University of Sheffield Hicks Building Hounsfield Road Sheffield S3 7RH U. K.National Astronomical Observatories Chinese Academy of SciencesBeijing 100012 Institute of Astrophysics & Geophysics Université de LiègeAllée du 6 Aot17Sart-Tilman (B5c)B-4000 LiègeBelgium

We review the long-term survival chances of young massive star clusters （YMCs）, hallmarks of intense starburst episodes often associated with Violent galaxy interactions. We address the key question as to whether at least some of these YMCs can be considered protoglobular clusters （GCs）, in which case these would be expected to evolve into counterparts of the ubiquitous old GCs believed to be among the oldest galactic building blocks. In the absence of significant external perturbations, the key factor determining a cluster＇s long-term survival chances is the shape of its stellar initial mass function （IMF）. It is, however, not straightforward to assess the IMF shape in unresolved extragalactic YMCs. We discuss in detail the promise of using high-resolution spectroscopy to make progress towards this goal, as well as the numerous pitfalls associated with this approach. We also discuss the latest progress in worldwide efforts to better understand the evolution of entire cluster systems, the disruption processes they are affected by, and whether we can use recently gained insights to determine the nature of at least some of the YMCs observed in extragalactic starbursts as proto-GCs. We conclude that there is an increasing body of evidence that GC formation appears to be continuing until today; their long-term evolution crucially depends on their environmental conditions, however.

关键词： stellar dynamics - globular clusters general - galaxies interactions - Magellanic Clouds - galaxies starburst - galaxies star clusters

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Map of Mafic Dyke Swarms and Related Units of Russia and Adjacent Regions

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Acta Geologica Sinica(english edition) 2016年第S1期90卷 22-23页

作者： richard e.eRNST Kenneth L.BUCHAN Svetlana BOTSYUN Department of earth Sciences Carleton University Faculty of Geology and Geography Tomsk State University Geological Survey of Canada Natural Resources Canada Laboratoire des Sciences du Climat et de l'environnement LSCE/IPSL CEA-CNRS-UVSQ Université Paris-Saclay

Work is currently underway to produce a map in Arc GISTM 10 of the mafic dyke swarms and related units(volcanics,sills and layered intrusions)of Russia and adjacent regions at a scale of 1:5,000,*** the past

关键词： Map of Mafic Dyke Swarms and Related Units of Russia and Adjacent Regions

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Diverse outcomes of species interactions in an invaded annual plant community

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Journal of Plant ecology 2017年第6期10卷 918-926页

作者： Claire e.Wainwright John M.Dwyer richard J.Hobbs Margaret M.Mayfield The ecology Centre School of Biological SciencesBuilding 8The University of QueenslandSt LuciaQueensland 4072Australia Commonwealth Scientific and Industrial Research Organisation Land and WaterEcoSciences PrecinctDutton ParkQueensland 4001Australia School of Plant Biology The University of Western Australia35 Stirling HighwayCrawleyWestern Australia 6009Australia

Aims Despite acknowledgement that interactions among native and exotic species are important for determining the structure and diversity of novel communities,directed experiments using mul-tiple exotics from the same system are *** observational studies have highlighted distinct ways that exotic species interface with resident natives across invaded *** correlative nature of these studies,however,has provided few details about the mechanisms driving distinct interaction outcomes within the same *** aim was to determine how three exotic annual plant species with distinct relationships with local plant diversity impact the performance of a co-occurring native annual in the York gum-jam woodlands of Western *** We grew species in experimental communities in growth chambers at varying total planting densities to assess how interaction out-comes varied among natives and exotics across a gradient of com-petition *** measured a variety of performance responses,including survival,biomass and population-level and individual-level reproductive *** Findings Overall,the effects of interspecific versus intraspecific competi-tion on performance varied with the identity and density of exotic *** exploitative exotic grass Bromus madritensis was dominant in polyculture,whereas the diminutive grass Pentameris airoides conferred weak intraspecific competition and interspe-cific facilitation on native Waitzia *** exotic broadleaf forb,Hypochaeris glabra,suppressed growth and survival of ***,while *** had weakly negative,neutral or positive effects on all *** outcomes highlight the complexity of interac-tions impacting the diversity,stability and structure of novel plant *** few of these communities contain a single exotic species,understanding the competitive dynamics occurring in diverse novel communities is critical for their conservation and restoration.

关键词： annual plants biotic interactions competition invasion novel ecosystems

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effect of drug therapies on self-reported chemosensory outcomes after COVID-19

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 88-96页

作者： Marco A.Fornazieri Bruno M.Cunha Samuel P.Nicácio Lucas K.Anzolin JoséL.B.da Silva Aristides Fernandes Neto Deusdedit Brandão Neto richard L.Voegels Fábio D.R.Pinna Department of Surgery Londrina State UniversityLondrinaBrazil Department of Medicine Pontifical Catholic University of ParanáLondrinaBrazil Department of Otorhinolaryngology University of São PauloSao PauloBrazil Department of Otorhinolaryngology:Head and Neck Surgery Perelman School of MedicineSmell and Taste CenterUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA

Objective:The aim of this study was to assess the relative efficacy of medications used following severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection on self-reported alterations in taste and/or smell ***:Seven hundred and fourteen persons with self-reported postcoronavirus disease 2019(post-COVID-19)chemosensory disorders were personally interviewed regarding specific medications they were administered following the acute phase of the *** dependent measure—self-reported total recovery of chemosensory symptoms—was subjected to stepwise logistic *** predictors included demographic and clinical variables,in addition to specific medications used to mitigate disease symptoms(i.e.,systemic corticosteroids,oseltamivir,vitamin C,ibuprofen,hydroxychloroquine,azithromycin,ivermectin,nitazoxanide,anticoagulants,and zinc).Results:The median time between COVID-19 symptom onset and the interviews was 81 days(interquartile range:60-104).Of the 714 subjects,249(34.9%)reported total recovery of their chemosensory function;437(61.2%)had at least one treatment since the beginning of the *** and those with more comorbidities had undergone more *** recovery rates of the treated and nontreated groups did not differ ***,respondents who had used nitazoxanide tended to have a higher rate of self-reported taste or smell *** who took oral zinc were less likely to ***:No medication employed during the first months after SARS-CoV-2 infection had a clear positive effect on returning self-reported smell or taste function to normal,although nitrazoxide trended in a positive *** zinc had a negative effect on the reported recovery of these senses.

关键词： chemosensory disorder coronavirus infections COVID-19 drug therapy SARS-CoV-2 smell loss taste loss

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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,Pelative 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 Pe-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 Peta-tocopherol,and three phenolics commonly found in alfalfa were~2.5-fold higher in pen-finished animals(all Pesting 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

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G-protein-coupled estrogen receptor as a new therapeutic target for treating coronary artery disease

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World Journal of Cardiology 2014年第6期6卷 367-375页

作者： Guichun Han richard e White Women’s Health Division Michael E DeBakey InstituteDepartment of Physiology and PharmacologyCollege of Veterinary Medicine and Biomedical SciencesTexas A and M UniversityCollege StationTX 77843United States Department of Biomedical Sciences Georgia Campus-Philadelphia College of Osteopathic MedicineSuwaneeGA 30024United States

Coronary heart disease(CHD) continues to be the greatest mortality risk factor in the developed world. estrogens are recognized to have great therapeutic potential to treat CHD and other cardiovascular diseases; however,a significant array of potentially debilitating side effects continues to limit their use. Moreover,recent clinical trials have indicated that long-term postmenopausal estrogen therapy may actually be detrimental to cardiovascular health. An exciting new development is the finding that the more recently discovered G-protein-coupled estrogen receptor(GPeR) is expressed in coronary arteries-both in coronary endothelium and in smooth muscle within the vascular wall. Accumulating evidence indicates that GPeR activation dilates coronary arteries and can also inhibit the prolif-eration and migration of coronary smooth muscle cells. Thus,selective GPeR activation has the potential to increase coronary blood flow and possibly limit the debilitating consequences of coronary atherosclerotic disease. This review will highlight what is currently known regarding the impact of GPeR activation on coronary arteries and the potential signaling mechanisms stimulated by GPeR agonists in these vessels. A thorough understanding of GPeR function in coronary arteries may promote the development of new therapies that would help alleviate CHD,while limiting the potentially dangerous side effects of estrogen therapy.

关键词： G-protein-coupled estrogen receptor Coronary arteries G-1 Atherosclerosis estrogen

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education and Core Competencies for Professional Hydrogeologists

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Journal of Groundwater Science and engineering 2013年第2期1卷 9-13页

作者： richard e.Jackson Geofirma engineering

Hydrogeologists may undergo initial education at the BS/BSc level as engineers,geoscientists or in another area of physical *** is a need in the 21 st Century to standardize the required competency profile of a professional hydrogeologist so that their professional certification is accepted *** is particularly the case in free-trade areas such as North America and the european Union where cross border consulting is economically *** is also important to foreign graduate students who will want to be assured that their academic qualification in hydrogeology will be accepted *** 1999 Bologna Accord in europe and the American Society of Civil engineer’s Body of Knowledge BOK2 report clearly indicate the growing acceptance of the BS/BSc degree as that of the engineer-in-training degree and that,in the words of the ASCe’s Committee on Academic Prerequisites for Professional Practice:“The outcome regarding specialized technical knowledge is best accomplished in a post-graduate program of *** not including technical specialization in the undergraduate program of study,necessary breadth can be achieved without increasing the size of the curriculum.” Thus,in the USA,by 2025 admission to an 8-hour written examination in the principles and practice of engineering will require that an engineering intern have:? A MSc degree in engineering from an accredited institution and 3 or more years of progressive experience,or ? A minimum of 30 additional appropriate credits from approved course providers plus 4 or more years of progressive *** the BS is the engineer-in-training degree and the MS is the professional engineer *** Bologna process has moved the eU nations towards a similar policy position with a first cycle/second cycle university system of 3+2 years leading to an Meng or MSc(eng) *** geo-engineering community in the US and europe have realized that they must respond to these developments a

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Principal Component Analysis of eBT2 Radiochromic Film for Multichannel Film Dosimetry

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International Journal of Medical Physics, Clinical engineering and Radiation Oncology 2014年第3期3卷 156-166页

作者： richard e. Wendt III Department of Imaging Physics The University of Texas M. D. Anderson Cancer Center Houston USA

Radiochromic film with a dye incorporated into the radiation sensitive layer [Gafchromic eBT2, Ashland, Inc.] may be digitized by a color transparency scanner, digitally processed, and calibrated so that a digital image in units of radiation absorbed dose is obtained. A transformation from raw scanner values to dose values was developed based upon a principal component analysis of the optical densities of the red, green and blue channels of the color image of a dose of 0.942 Gy delivered by a Sr-90/Y-90 disk-shaped source. In the order of increasing eigenvalue, the three eigenimages of the principal component analysis contained, by visual inspection, 1) mainly noise;2) mainly a pattern of irregular streaks;and 3) most of the expected dose information along with some of the same background streaking that predominated in the second eigenimage. The combination of the second and third eigenimages that minimized the background streaking was converted into a transformation of the red, green and blue channels’ optical densities and applied to films with a range of doses from 0 to 63.7 Gy. The curve of dose vs. processed optical density was fit by a two-phase association curve. This processing was applied to a film exposed from its edge by a different Y-90 source in a configuration that was modeled by Monte Carlo simulation. The depth-dose curves of the measurement and simulation agree closely, suggesting that this approach is a valid method of processing eBT2 radiochromic film into maps of radiation absorbed dose.

关键词： Principal Component Analysis Radiochromic Film Multichannel Film Dosimetry

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Game Theoretical Approach for Non-Overlapping Community Detection

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Tsinghua Science and Technology 2021年第5期26卷 706-723页

作者： Baohua Sun richard Al-Bayaty Qiuyuan Huang Dapeng Wu the Department of electrical and Computer engineering University of FloridaGainesvilleFL 32611USA

Graph clustering,i.e.,partitioning nodes or data points into non-overlapping clusters,can be beneficial in a large varieties of computer vision and machine learning ***,main graph clustering schemes,such as spectral clustering,cannot be applied to a large network due to prohibitive computational complexity *** there exist methods applicable to large networks,these methods do not offer convincing comparisons against known ground *** the first time,this work conducts clustering algorithm performance evaluations on large networks(consisting of one million nodes)with ground truth *** and concepts from game theory are applied towards graph clustering to formulate a new proposed algorithm,Game Theoretical Approach for Clustering(GTAC).This theoretical framework is shown to be a generalization of both the Label Propagation and Louvain methods,offering an additional means of derivation and *** introduces a tuning parameter which allows variable algorithm performance in accordance with application *** shows that these GTAC algorithms offer scalability and tunability towards big data applications.

关键词： big data analytics game theory clustering community detection label propagation

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Mental health status in veterans residing in rural versus non-rural areas: results from the veterans’ health study

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Military Medical Research 2021年第1期8卷 79-89页

作者： Joseph J.Boscarino Charles R.Figley richard e.Adams Thomas G.Urosevich H.Lester Kirchner Joseph A.Boscarino Clinical Psychology Department William James CollegeNewtonMA 02459USA School of Social Work Tulane UniversityNew OrleansLA 70112USA Department of Sociology Kent State UniversityKentOH 44242USA Ophthalmology Service Geisinger ClinicMount PoconoPA 18344USA Department of Population Health Sciences Geisinger Clinic100 N.Academy Avenue44-00DanvillePA 17822USA

Background: The majority of Veterans Affair(VA) hospitals are in urban areas. We examined whether veterans residing in rural areas have lower mental health service use and poorer mental health ***: Veterans with at least 1 warzone deployment in central and northeastern Pennsylvania were randomly selected for an interview. Mental health status, including posttraumatic stress disorder(PTSD), major depression, alcohol abuse and mental health global severity, were assessed using structured interviews. Psychiatric service use was based on self-reported utilization in the past 12 months. Results were compared between veterans residing in rural and non-rural areas. Data were also analyzed using multivariate logistic regression to minimize the influence by confounding ***: A total of 1730 subjects(55% of the eligible veterans) responded to the survey and 1692 of them had complete geocode information. Those that did not have this information(n=38), were excluded from some analyses. Veterans residing in rural areas were older, more often of the white race, married, and experienced fewer stressful events. In comparison to those residing in non-rural areas, veterans residing in rural areas had lower global mental health severity scores;they also had fewer mental health visits. In multivariate logistic regression, rural residence was associated with lower service use, but not with PTSD, major depression, alcohol abuse, and global mental health severity score after adjusting confounding factors(e.g., age, gender, marital status and education).Conclusions: Rural residence is associated with lower mental health service use, but not with poor mental health in veterans with former warzone deployment, suggesting rural residence is possibly protective.

关键词： Veterans Rural Risk factors PTSD Alcohol abuse Depression Service use Census data

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