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Neutrinos,supernovae,and the origin of the heavy elements

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Science China(Physics,Mechanics & Astronomy) 2018年第4期61卷 1-6页

作者： YongZhong Qian School of Physics and Astronomy University of MinnesotaMinneapolis 55455USA Tsung-Dao Lee Institute Shanghai 200240China

Stars of～8-100 M_⊙end their lives as core-collapse supernovae(SNe). In the process they emit a powerful burst of neutrinos,produce a variety of elements, and leave behind either a neutron star or a black hole. The wide mass range for SN progenitors results in diverse neutrino signals, explosion energies, and nucleosynthesis products. A major mechanism to produce nuclei heavier than iron is rapid neutron capture, or the r process. This process may be connected to SNe in several ways. A brief review is presented on current understanding of neutrino emission, explosion, and nucleosynthesis of SNe.

关键词： neutrino supernova nucleosynthesis the r process

Role of innate immunity in the development of hepatocellular carcinoma

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World Journal of Gastroenterology 2013年第43期19卷 7500-7514页

作者： Rajagopal N Aravalli Department of Radiology University of Minnesota Medical SchoolMinneapolisMN 55455United States

Hepatocellular carcinoma(HCC)is the most common form of liver cancer *** is caused by a variety of risk factors,most common ones being infection with hepatitis viruses,alcohol,and *** often develops in the background of underlying cirrhosis,and even though a number of interventional treatment methods are currently in use,recurrence is fairly common among patients who have had a ***,whole liver transplantation remains the most practical treatment option for *** to the growing incidence of HCC,intense research efforts are being made to understand cellular and molecular mechanisms of the disease so that novel therapeutic strategies can be developed to combat liver *** recent years,it has become clear that innate immunity plays a critical role in the development of a number of liver diseases,including *** particular,the activation of Toll-like receptor signaling results in the generation of immune responses that often results in the production of proinflammatory cytokines and chemokines,and could cause acute inflammation in the *** this review,the current knowledge on the role of innate immune responses in the development and progression of HCC is examined,and emerging therapeutic strategies based on molecular mechanisms of HCC are discussed.

关键词： Hepatocellular carcinoma Innate immunity Toll-like receptor Liver cancer Inflammation

Bioaccumulation of toxic hydrophobic organic compounds at the primary trophic level

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Journal of Environmental Sciences 1991年第3期3卷 15-21页

作者： Deborah L.Swackhamer Environmental and Occupational Health School of Public Health University of Minnesota Minneapolis USA.

The prevailing hypothesis, which states that the uptake of HOCs by phytoplankton is controlled by the compound's lipophilicity (Kow) was tested. The approach taken was to determine the factors that controlled the uptake of PCBs by phytoplankton under controlled laboratory conditions, and to develop a model that would describe bioaccumulation of PCBs in *** results demonstrate a relationship of BAF to Kow and to phytoplankton surface properties, as well as the data presented here, support the hypothesis that the mechanism of HOC uptake is a rapid surface sorption followed by a slower transfer into lipids in the cell matrix. The work on the kinetics of uptake indicates that equilibrium is reached slowly and that the rate of uptake is of similar magnitude as phytoplankton growth under normal field *** a critical factor that controls the bioaccumulation of HOCs reach equilibrium in phytoplankton itself.

关键词： bioaccumulation hydrophobic organic compounds PCBs phytoplankton dynamic approach.

A cautionary note on decadal sea level pressure predictions from GCMs

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Advances in Climate Change Research 2018年第1期9卷 43-56页

作者： Stefan LIESS Peter K.SNYDER Arjun KUMAR Vipin KUMAR Department of Earth Sciences University of MinnesotaMinneapolis MN 55455USA Department of Soil Waterand ClimateUniversity of MinnesotaSt.Paul MN 55108USA Computer Science&Engineering University of MinnesotaMinneapolis MN 55455USA

A comparison of sea level pressure(SLP)trends in a subset of seven Coupled Model Intercomparison Project(CMIP)phase 5 general circulation models(GCM),namely decadal simulations with CCSM4,CanCM4,MPI-ESM-LR,FGOALS-g2,MIROC4h,MIROC5,and MRICGCM3,to their CMIP3 counterparts reveals an unrealistically strong forecast skill in CMIP3 models for trend predictions for 2001e2011 when using the 1979e2000 period to train the ***-winter SLP trends over five high-,mid-,and low-latitude zones were calculated over the 1979e2000 initialization period for each ensemble member and then ranked based on their performance relative to HadSLP2 *** same method is used to rank the ensemble members during the 2001e2011 *** CMIP3,17 out of 38 ensemble members retain their rank in the 2001e2011 hindcast period and 3 retain the neighboring ***,numbers are much lower in more recent CMIP5 decadal predictions over the similar 2001e2010 period when using the 1981e2000 period as initialization with the same number of *** periods were used for CMIP3 and CMIP5 because although the 1979e2000 initialization is widely used for CMIP3,CMIP5 decadal predictions are only available for 30-year *** conclusion to consider the forecast skill in CMIP3 predictions during 2001e2011 as unrealistic is corroborated by comparisons to earlier periods from the 1960s to the 1980s in both CMIP3 and CMIP5 ***,although the 2001e2011 CMIP3 predictions show statistically significant forecast skill,this skill should be treated as a spurious result that is unlikely to be reproduced by newer more accurate GCMs.

关键词： sea level pressure CMIP3 Coupled Model Intercomparison Project

Methods to Identify Individual Eddy Structures in Turbulent Flow

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Tsinghua Science and Technology 2013年第2期18卷 125-136页

作者： Shengwen Wang Jack Goldfeather Ellen K. Longmire Victoria Interrante the Department of Computer Science and Engineering University of Minnesota Minneapolis MN 55455 USA the Mathematics and Computer Science Department Carleton College Northfield MinnesotaMN 55057 USA the Department of Aerospace Engineering and Mechanics University of MinnesotaMinneapolis MN 55455 USA

Turbulent flows are intrinsic to many processes in science and engineering, and efforts to elucidate the physics of turbulence are of critical importance to many fields. However, ongoing efforts to achieve a fundamental understanding of the mechanisms of turbulent flow are hindered by the difficulty of quantifying the complex, nonlinear interactions between individual eddies in these flows. The difficulty of this task is compounded by the lack of robust methods for accurately identifying individual eddy structures and characterizing their dynamic evolution and organization across multiple scales. In this paper we address this problem by proposing several novel approaches for more accurately segmenting individual eddy structures in turbulent flows.

关键词： flow visualization segmentation vortices turbulent flow

Risk factors for 90-day readmission in veterans with inflammatory bowel disease——Does post-discharge follow-up matter?

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Military Medical Research 2018年第3期5卷 216-221页

作者： Ashish Malhotra Parkpoom Phatharacharukul Charat Thongprayoon Center of Innovation Minneapolis VA Health Care System Division of Gastroenterology Department of Medicine Minneapolis VA Medical Center Department of Medicine University of Minnesota School of Medicine Department of Internal Medicine Bassett Medical Center

Background: Repeat hospitalizations in veterans with inflammatory bowel disease(IBD) are under studied. The early readmission rate and potentially modifiable risk-factors for 90-day readmission in veterans with IBD were studied to avert avoidable ***: A retrospective cohort study was conducted using the data from veterans who were admitted to the minneapolis VA Medical Center(MVMC) between January 1, 2007, and December 31, 2013, for an IBD-related problem. All-cause readmissions within 30 and 90 days were recorded to calculate early readmission rates. The multivariate logistic regression was used to identify the potential risk factors for 90-day ***: There were 130 unique patients(56.9% with Crohn's disease and 43.1% with ulcerative colitis) with 202 IBD-related index admissions. The mean age at the time of index admission was 59.8±15.2 years. The median time to re-hospitalization was 26 days(IQR 10-49), with 30-and 90-day readmission rates of 17.3%(35/202) and 29.2%(59/202), respectively. Reasons for all-cause readmission were IBD-related(71.2%), scheduled surgery(3.4%) and non-gastrointestinal causes(25.4%). The following reasons were independently associated with 90-day readmission: Crohn's disease(OR 3.90; 95% CI 1.82-8.90), use of antidepressants(OR 2.19; 95% CI 1.12-4.32), and lack of follow-up within 90 days with a primary care physician(PCP)(OR 2.63; 95% CI 1.32-5.26) or a gastroenterologist(GI)(OR 2.44; 95% CI 1.20-5.00). 51.0% and 49.0% of patients had documentation of a recommended outpatient follow-up with PCP and/or GI, ***: Early readmission in IBD is common. Independent risk factors for 90-day readmission included Crohn's disease, use of antidepressants and lack of follow-up visit with PCP or GI. Further research is required to determine if the appropriate timing of post-discharge follow-up can reduce IBD readmissions.

关键词： Inflammatory bowel disease Readmission rates Veterans affairs

A resampling approach to estimation of the linking variance in the Fay–Herriot model

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Statistical Theory and Related Fields 2019年第2期3卷 170-177页

作者： Snigdhansu Chatterjee School of Statistics University of MinnesotaMinneapolisMNUSA

In the Fay–Herriot model,we consider estimators of the linking variance obtained using different types of resampling *** usefulness of this approach is that even when the estimator from the original data falls below zero or any other specified threshold,several of the resamples can potentially yield values above the *** establish asymptotic consistency of the resampling-based estimator of the linking variance for a wide variety of resampling schemes and show the efficacy of using the proposed approach in numeric examples.

关键词： Linking variance Prasad–Rao estimator paired bootstrap m-out-of-n bootstrap Bayesian bootstrap

BOUNDARY CONTROL OF TWO PDE'S SEPARATED BY INTERFACE CONDITIONS

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Journal of Systems Science & Complexity 2010年第3期23卷 431-437页

作者： Orazio ARENA Walter LITTMAN Dipartimento di Matematica e Applicazioni per l'Architettura Universit di Firenze School of Mathematics University of Minnesota Minneapolis

This paper discusses the null boundary controllability of two PDE's,modeling a compositesolid with different physical properties in each *** conditions are imposed.

关键词： Heat equation interface condition null boundary control Schroinger equation.

Application of network meta-analysis in the field of physical activity and health promotion

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Journal of Sport and Health Science 2020年第6期9卷 511-520页

作者： Xiwen Su Daniel J.McDonough Haitao Chu Minghui Quan Zan Gao School of Kinesiology University of MinnesotaMinneapolisMN 55455USA Division of Biostatistics School of Public HealthUniversity of MinnesotaMinneapolisMN 55455USA School of Kinesiology Shanghai University of SportShanghai 200438China

Continued advancement in the field of physical activity and health promotion relies heavily on the synthesis of rigorous scientific *** such,systematic reviews and meta-analyses of randomized controlled trials have led to a better understanding of which intervention strategies are superior(i.e.,produce the greatest effects)in physical activity-based health behavior change ***,standard meta-analytic approaches have allowed researchers in the field to synthesize relevant experimental evidence using pairwise procedures that produce reliable estimates of the homogeneity,magnitude,and potential biases in the observed ***,pairwise meta-analytic procedures are only capable to discerning differences in effects between a select intervention strategy and a select comparison or control *** order to maximize the impact of physical activity interventions on health-related outcomes,it is necessary to establish evidence concerning the comparative efficacy of all relevant physical activity intervention *** development of network meta-analysis(NMA)-most commonly used in medical-based clinical trials-has allowed for the quantification of indirect comparisons,even in the absence of direct,head-to-head ***,it stands to reason that NMA can be applied in physical activity and health promotion research to identify the best intervention *** that this analysis technique is novel and largely unexplored in the field of physical activity and health promotion,care must be taken in its application to ensure reliable estimates and discernment of the effect sizes among ***,the purpose of this review is to comment on the potential application and importance of NMA in the field of physical activity and health promotion,describe how to properly and effectively apply this technique,and suggest important considerations for its appropriate application in this *** this paper,overviews of the foundations

关键词： Behavior change Kinesiology and health promotion Multiple treatment comparison Pairwise meta-analysis Randomized controlled trials