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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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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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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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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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Ultrasound liver elastography beyond liver fibrosis assessment

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World Journal of Gastroenterology 2020年第24期26卷 3413-3420页

作者： Giovanna Ferraioli richard G Barr Dipartimento di Scienze Clinico-Chirurgiche Diagnostiche e PediatricheMedical School University of PaviaPavia 27100Italy Northeastern Ohio Medical University RootstownOH 44272United States

Several guidelines have indicated that liver stiffness(LS)assessed by means of shear wave elastography(SWe)can safely replace liver biopsy in several clinical scenarios,particularly in patients with chronic viral ***,an increase of LS may be due to some other clinical conditions not related to fibrosis,such as liver inflammation,acute hepatitis,obstructive cholestasis,liver congestion,infiltrative liver *** review analyzes the role that SWe can play in cases of liver congestion due to right-sided heart failure,congenital heart diseases or valvular *** patients with heart failure LS seems directly influenced by central venous pressure and can be used as a prognostic marker to predict cardiac *** potential role of LS in evaluating liver disease beyond the stage of liver fibrosis has been investigated also in the hepatic sinusoidal obstruction syndrome(SOS)and in the Budd-Chiari *** the hepatic SOS,an increase of LS is observed some days before the clinical manifestations;therefore,it could allow an early diagnosis to timely start an effective ***,it has been reported that patients that were successfully treated showed a LS decrease,that reached pre-transplantation value within two to four *** has been reported that,in patients with Budd-Chiari syndrome,LS values can be used to monitor short and long-term outcome after angioplasty.

关键词： Liver stiffness Shear wave elastography Heart failure Liver congestion Hepatic sinusoidal obstruction syndrome Fontan circulation Budd Chiari syndrome Valvular diseases

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Postmyotomy dysphagia after laparoscopic surgery for achalasia

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World Journal of Gastroenterology 2003年第5期9卷 1129-1131页

作者： Yutaka Shiino Ziad T.Awad Gleb R. Haynatzki richard e. Davis Ronald A. Hinder Charles J. Filipi Department of Surgery Creighton University601 N.30~(th)StreetOmahaNE 68131USA Department of Medicine Creighton University601 N.30~(th) StreetOmahaNE 68131USA Department of Surgery Mayo Clinic Jacksonville4500 San Pablo RoadJacksonvilleFL 32224USA

AIM: To determine predictive factors for postoperative dysphagia after laparoscopic myotomy for ***: Logistic regression was used to investigate the possible association between the response (postoperative dysphagia, with two levels: none/mild and moderate/severe)and several plausible predictive ***: eight patients experienced severe or moderate postoperative dysphagia. The logistic regression revealed that only the severity of preoperative dysphagia (with four levels; mild, moderate, severe, and liquid) was a marginally significant (P=0.0575) predictive factor for postoperative ***: The severity of postoperative dysphagia is strongly associated with preoperative dysphagia. Preoperative symptomatology can significantly impact patient outcome.

关键词： Deglutition Disorders Digestive System Surgical Procedures esophageal Achalasia Female Humans Laparoscopy Logistic Models Male Postoperative Complications Retrospective Studies Risk Factors Treatment Outcome

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TLR signaling that induces weak inflammatory response and SHIP1 enhances osteogenic functions

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Bone Research 2014年第4期2卷 218-230页

作者： Manoj Muthukuru richard P Darveau West Virginia University Department of PeriodonticsSchool of DentistryMorgantownWVUSA University of Washington Department of PeriodonticsSchool of DentistrySeattleWAUSA

Toll-like receptor （TLR）-mediated inflammatory response could negatively affect bone metabolism. In this study, we determined how osteogenesis is regulated during inflammatory responses that are downstream of TLR signaling. Human primary osteoblasts were cultured in collagen gels. Pam3CSK4 （P3C） and escherichia coli lipopolysaccharide （ecLPS） were used as TLR2 and TLR4 ligand respectively. Porphyromonas gingivalis LPS having TLR2 activity with either TLR4 agonism （Pg1690） or TLR4 antagonism （Pg1449） and mutant e. coli LPS （LPxe/LPxF/WSK） were used. IL-lp, SH2-containing inositol phosphatase-1 （SHIP1） that has regulatory roles in osteogenesis, alkaline phosphatase and mineralization were analyzed. 3α-Aminocholestane （3AC） was used to inhibit SHIP1. Our results suggest that osteoblasts stimulated by P3C, poorly induced IL-1β but strongly upregulated SHIP1 and enhanced osteogenic mediators. On the contrary, ecLPS significantly induced IL-1β and osteogenic mediators were not induced. While Pg1690 downmodulated osteogenic mediators, Pg1449 enhanced osteogenic responses, suggesting that TLR4 signaling annuls osteogenesis even with TLR2 activity. Interestingly, mutant e. coli LPS that induces weak inflammation upregulated osteogenesis, but SHIP1 was not induced. Moreover, inhibiting SHIP1 significantly upregulated TLR2-mediated inflammatory response and downmodulated osteogenesis. In conclusion, these results suggest that induction of weak inflammatory response through TLR2 （with SHIP1 activity） and mutant TLR4 ligands could enhance osteogenesis.

关键词： TLR signaling that induces weak inflammatory response and SHIP1 enhances osteogenic functions SHIP Figure

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Appraisal of active tectonics in Hindu Kush:Insights from DeM derived geomorphic indices and drainage analysis

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Geoscience Frontiers 2012年第4期3卷 407-428页

作者： Syed Amer Mahmood richard Gloaguen Remote Sensing Group Institute of GeologyFreiberg University of Mining and TechnologyBernhard V.Cotta Str209599 Freiberg(Saxony)Germany Department of Space Science University of the PunjabQuaid-e-Azam Campus54590Lahore(Punjab)Pakistan Remote Sensing Group Institute of GeologyFreiberg University of Mining and TechnolohyBernhard V.Cotta Str.209599 Freiberg(Saxony)Germany

Landscapes in tectonically active Hindu Kush （NW Pakistan and Ne Alghanistanl result from a complex integration of the effects of vertical and horizontal crustal block motions as well as erosion and deposition processes. Active tectonics in this region have greatly influenced the drainage system and geomorphic expressions. The study area is a junction of three important mt^unlain ranges （Hindu Kush-Karakorunl-Himalayas） and is thus an ideal natural laboratory to investigate the relative tectonic activity resulting from the India-eurasia collision. We evaluate active tectonics using DeM derived drainage network and geomorphic indices hypsometric integral （Hl）. stream-length gradient （SL）, fractal dimension （FD）, basin asymmetry factor （AF）, basin shape index （B,）, valley floor width to wllley height ratio （Vf） and motmtain front sinuosity （Star）. The results obtained from these indices were combined to yield an index of relative active tectonics （IRAT） using GIS. The average of the seven measured geomorphic indices was used to ewfluate the distri- bution of relative tectonic activity in the study area. We defined tour classes to define the degree of rela- tive tectonic activity： class 1 very high （1.0 ≤ IRAT 〈 1.3）; class 2 high （1.3 ≥ IRAT 〈 1.5）： class 3--moderate （1.5 〉 IRAT 〈 1.8）; and class 4--low （1.8 〉 IRAT）. In view of the results, we conclude that this combined approach allows the identification of the highly deformed areas related to active tectonics. Landsat imagery and field observations also evidence the presence of active tectonics based on the deflected streams, deformed landforms, active mountain fronts and triangular facets. The indicative values of IRAT are consistent with the areas of known relative uplift rates, landforms and geology.

关键词： Active tectonics:Geomorphic indices:IRAT (index of relativeactive tectonics):Hindu Kush:Pakistan--Alghanistan

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