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Equilibrium Energy and Entropy of Vortex Filaments in the Context of Tornadogenesis and Tornadic Flows

Open Journal of Fluid Dynamics 2023年第3期13卷 144-176页

作者： Pavel bělík douglas P. Dokken Mikhail M. Shvartsman Eric bibelnieks Robert Laskowski Alek Lukanen Department of Mathematics Statistics and Computer Science Augsburg University Minneapolis USA Department of Mathematics University of St. Thomas St. Paul USA

In this work, we study approximations of supercritical or suction vortices in tornadic flows and their contribution to tornadogenesis and tornado maintenance using self-avoiding walks on a cubic lattice. We extend the previous work on turbulence by A. Chorin and collaborators to approximate the statistical equilibrium quantities of vortex filaments on a cubic lattice when both an energy and a statistical temperature are involved. Our results confirm that supercritical (smooth, “straight”) vortices have the highest average energy and correspond to negative temperatures in this model. The lowest-energy configurations are folded up and “balled up” to a great extent. The results support A. Chorin’s findings that, in the context of supercritical vortices in a tornadic flow, when such high-energy vortices stretch, they need to fold and transfer energy to the surrounding flow, contributing to tornado maintenance or leading to its genesis. The computations are performed using a Markov Chain Monte Carlo approach with a simple sampling algorithm using local transformations that allow the results to be reliable over a wide range of statistical temperatures, unlike the originally used pivot algorithm that only performs well near infinite temperatures. Efficient ways to compute entropy are discussed and show that a system with supercritical vortices will increase entropy by having these vortices fold and transfer their energy to the surrounding flow.

关键词： Tornadogenesis Supercritical Vortices Vortex Filaments Negative Temperature Kinetic Energy Entropy Statistical Mechanics Equilibrium Statistics Self-Avoiding Walks Cubic Lattice Monte-Carlo Techniques Pivot Algorithm

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国际机械振动与冲击标准社会作用的变化(下)

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中国设备工程 2002年第2期 51-53页

作者： b.E.douglas ,李敏

四、标准化中的技术覆盖--一个案例:机械的状态监测一项'良好的'技术标准,它的重要特征之一是具有宽广的应用覆盖面.但是,标准的适用范围愈广,它和其它技术委员会所制定的标准之间出现彼此覆盖的几率就愈大.

关键词：机械振动 TC ISO 名词术语工作组状态监测国际标准化组织

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国际机械振动与冲击标准社会作用的变化(上)

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中国设备工程 2002年第1期 49-51页

作者： b.E.douglas 李敏美

随着先进技术日益深入地渗透到对全世界许多人的日常生活至关重要的各个系统中,为了更好地保证实际业务得以公平合理地进行、保护公共安全和保护环境,对高质量技术标准的需要已变得愈来愈迫切。本文涉及机械振动与冲击领域中技术标准化... 详细信息

随着先进技术日益深入地渗透到对全世界许多人的日常生活至关重要的各个系统中,为了更好地保证实际业务得以公平合理地进行、保护公共安全和保护环境,对高质量技术标准的需要已变得愈来愈迫切。本文涉及机械振动与冲击领域中技术标准化的诸多问题,重点为机器和结构的状态监测。文中谈到的具体问题包括:(1)机械振动与冲击领域中标准化的社会目标;(2)各方赞助者的经济利害关系和潜在的冲突方面;(3)ISO/TC108的组织结构、工作过程和业务计划;(4)这些标准广泛应用于机器和结构的状态监测的例子。

关键词：机械振动冲击机器技术标准国

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Hepatocellular carcinoma,human immunodeficiency virus and viral hepatitis in the HAART era

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World Journal of Gastroenterology 2008年第11期14卷 1657-1663页

作者： douglas C Macdonald Mark Nelson Mark bower Thomas Powles Chelsea and Westminster hospital LondonUnited Kingdom St bartholomew’s Hospital LondonUnited Kingdom

The incidence of hepatocellular carcinoma(HCC)in patients with human immunodeficiency virus(HIV) is *** in HIV almost invariably occurs in the context of hepatitis C virus(HCV)or hepatitis b virus (HbV)co-infection and,on account of shared modes of transmission,this occurs in more than 33% and 10% of patients with HIV worldwide *** has yet to be clearly established whether HIV directly accelerates HCC pathogenesis or whether the rising incidence is an epiphenomenon of the highly active antiretroviral therapy(HAART)era,wherein the increased longevity of patients with HIV allows long-term complications of viral hepatitis and cirrhosis to *** this question will have implications for HCC surveillance and the timing of HCV/HbV therapy,which in HIV co-infection presents unique *** HCC develops,there is growing evidence that HIV co-infection should not preclude conventional therapeutic strategies,including liver transplantation.

关键词： Hepatocellular carcinoma Human immunodeficiency virus hepatitis Hepatitis b virus Hepatitis C virus Co-infection Incidence Transplant Pathogenesis

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Applications of Vortex Gas Models to Tornadogenesis and Maintenance

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Open Journal of Fluid Dynamics 2017年第4期7卷 596-622页

作者： Pavel bělík douglas P. Dokken Corey K. Potvin Kurt Scholz Mikhail M. Shvartsman Department of Mathematics Statistics and Computer Science Augsburg University Minneapolis MN USA Department of Mathematics University of St. Thomas St. Paul MN USA Cooperative Institute for Mesoscale Meteorological Studies School of Meteorology University of Oklahoma NOAA/OAR/National Severe Storms Laboratory Norman OK USA

Processes related to the production of vorticity in the forward and rear flank downdrafts and their interaction with the boundary layer are thought to play a role in tornadogenesis. We argue that an inverse energy cascade is a plausible mechanism for tornadogenesis and tornado maintenance and provides supporting evidence which is both numerical and observational. We apply a three-dimensional vortex gas model to supercritical vortices produced at the surface boundary layer possibly due to interactions of vortices brought to the surface by the rear flank downdraft and also to those related to the forward flank downdraft. Two-dimensional and three-dimensional vortex gas models are discussed, and the three-dimensional vortex gas model of Chorin, developed further by Flandoli and Gubinelli, is proposed as a model for intense small-scale subvortices found in tornadoes and in recent numerical studies by Orf et al. In this paper, the smaller scales are represented by intense, supercritical vortices, which transfer energy to the larger-scale tornadic flows (inverse energy cascade). We address the formation of these vortices as a result of the interaction of the flow with the surface and a boundary layer.

关键词： Vortex Gas Negative Temperature Supercritical Vortices Inverse Energy Cascade Tornadogenesis Tornado Maintenance

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A genome-wide scan for pleiotropy between bone mineral density and nonbone phenotypes

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bone Research 2020年第3期8卷 356-364页

作者： Maria A.Christou Georgios Ntritsos Georgios Markozannes Fotis Koskeridis Spyros N.Nikas David Karasik douglas P.Kiel Evangelos Evangelou Evangelia E.Ntzani Department of Hygiene and Epidemiology Clinical and Molecular Epidemiology UnitSchool of MedicineUniversity of loanninaloanninaGreece Department of Medicine Beth Israel Deaconess Medical CenterHarvard Medical SchoolHinda and Arthur Marcus Institute for Aging ResearchHebrew SeniorLifeand the Broad Institute of MIT&HarvardCambridgeMAUSA Azrieli Faculty of Medicine Bar llan UniversitySafedIsrael Department of Epidemiology and biostatistics Imperial College LondonLondonUK Department of Health Services Policy and PracticeCenter for Research Synthesis in HealthSchool of Public HealthBrown UniversityProvidenceRlUSA

Osteoporosis is the most common metabolic bone disorder globally and is characterized by skeletal fragility and microarchitectural *** pleiotropy occurs when a single genetic element is associated with more than one *** aimed to identify pleiotropic loci associated with bone mineral density(bMD)and nonbone phenotypes in genome-wide association *** the discovery stage,the NHGRI-EbI Catalog was searched for genome-wide significant associations(P valuebone-related *** was used to identify proxies of the significantly associated single nucleotide polymorphisms(SNPs)(r2=1).We then assessed putative genetic associations of this set of SNPs with femoral neck(FN)and lumbar spine(LS)bMD data from the GEFOS *** variants were claimed at a false discovery ratebMD andbiobank participants of European ancestry with available genetic and heel bone ultrasound *** the discovery stage,72 bMD-related pleiotropic SNPs were identified,and 12 SNPs located in 11 loci on 8 chromosomes were replicated in the UK *** SNPs were associated,in addition to bMD,with 14 different *** pleiotropic associations were exhibited by rs479844(AP5b1,O V O L 1 genes),which was associated with dermatological and allergic diseases,and rs4072037(M U C 1 gene),which was associated with magnesium levels and gastroenterological *** conclusion,12 bMD-related genome-wide significant SNPs showed pleiotropy with nonbone *** associations can deepen the genetic understanding of bone-related diseases by identifying shared biological mechanisms with other diseases or traits.

关键词： magnesium globally Replication

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Epidemiological Characteristics of Influenza A and b in Macao,2010–2018

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Virologica Sinica 2021年第5期36卷 1144-1153页

作者： HoiMan Ng Teng Zhang Guoliang Wang SiMeng Kan Guoyi Ma Zhe Li Chang Chen Dandan Wang MengIn Wong ChioHang Wong Jinliang Ni Xiaohua douglas Zhang Clinical Laboratory Kiang Wu HospitalMacao 999078Macao Faculty of Health Sciences University of MacaoMacao 999078Macao

Influenza is one of the major respiratory diseases in *** is a tourist city with high density of population and special population *** study on the epidemiological characteristics of influenza in Macao should bring great value for preventing influenza in tourist cities like Macao in the *** this study,we collected a total of 104,874 samples with influenza-like illness(ILI)in Macao from 2010 to ***-square test and binary multivariable logistic regression were used to investigate the epidemiological characteristics of influenza A and b in *** these ILI samples,the overall positive rate is 17.17%for influenza A and 6.97%for influenza *** epidemics of influenza in three years(i.e.,2012,2017 and 2018)differ from the remaining years(i.e.,normal years).In a normal year,influenza A occurs year-round whereas influenza b is *** research shows significant differences in influenza infections between different age groups in normal ***,our analysis shows no significant difference between locals and tourists in influenza A and b infection in a normal year,whereas the odds of influenza A in tourists were significantly higher than those in locals in July 2017 and the odds of influenza b in tourists were significantly higher than those in locals in January–February 2012 and January–February *** is possibly attributed by the policy of free vaccination to everyone in *** findings should be valuable for preventing influenza in not only Macao but also the world.

关键词： Influenza Epidemiology Chi-square test Logistic regression Macao

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Influence of Geomorphology on Fish Fauna of a Small Mississippi bluffline Stream

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Journal of Environmental Science and Engineering(b) 2015年第4期4卷 169-176页

作者： Scott Stephen Knight Terry douglas Welch United States Department of Agriculture Agricultural Research Service National Sedimentation Laboratory Oxford MS 38655 USA

Fish were collected from 39 sites on the main channel and major tributaries of a highly erosive stream, Hotophia Creek. A total of 2,642 specimens representing 38 species were collected between 1986 through 2003. The bluntface shiner Cyprinella camura was the dominant species of fish and when grouped with other cyprinids accounted for 38.0% of the total numbers collected. by weight, Lepisosteusoculatus, Lepomismegalotis, lctiobusbubalus, and Lepomismacrochirus were the dominant species; accounting for 49.9% of the total catch. While more diminutive species such as cyprinids that might be subject to predation by large fish more frequently were found in shallow channels. Fishes with specific habitat requirement such as the pirate perch were found in the middle group of sites, that were disturbed by erosion process but that featured the necessary habitat requirements. Sensitive or intolerant species like the Yazoo darter, creek chubsucker and cyprinids in general were more frequently found in the undisturbed and habitat complex channels. This study supports the hypothesis that geomorphological stream stages are associated with specific communities of fishes.

关键词： Stream classification geomorphology index of biotic integrity ecology.

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Effect of Antimicrobial Myrrh on the Color and Viscosity of Plain Yogurt over Its Shelf Life

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Food and Nutrition Sciences 2019年第10期10卷 1236-1242页

作者： Mohammed Alhejaili douglas Olson Kayanush Aryana School of Nutrition and Food Sciences Louisiana State University Agricultural Center Baton Rouge LA USA

Myrrh, commercially available as a brown powder, is a natural flavoring substance approved for food use by US Food and Drug Administration and has antibacterial and antifungal activity against pathogens. Myrrh is commercially available as a brown powder. The objective was to determine the effect of myrrh on the color (L*, a*, b*, C*, h*) and viscosity of yogurt over refrigerated storage. Myrrh dispersion was prepared and incorporated at a 1% v/v level into yogurt. A control with no myrrh was also prepared. Three replications were conducted. At a small usage level of 1% v/v, myrrh influenced the color attributes L*, a* and h* but did not influence the viscosity of the plain yogurts.

关键词： Antimicrobial Fermented Myrrh

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Evaluation of H3A for Determination of Plant Available P vs. FeAlO Strips

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Open Journal of Soil Science 2016年第11期6卷 175-187页

作者： Richard L. Haney Elizabeth b. Haney R. Daren Harmel douglas R. Smith Mike J. White Grassland Soil and Water Research Laboratory USDA-ARS Temple TX USA Texas Agri Life Research and Extension Center Texas A&M University Temple TX USA

Phosphorus is an essential nutrient for plant growth but in excess is a source of environmental pollution. Fertilizer additions of P are recommended based on soil tests;however, the commonly applied P extractants are often applied outside of their design criteria (specifically soil pH). As a result, soil tests can produce inaccurate estimates of plant available P in the soil, which either increases P loss in runoff, contributing to eutrophication, or decreases crop production contributing to economic loss. In this study, 200 diverse soils from across the US were extracted with Mehlich 3, water, H3A-3, and FeAlO strips. Comparison with FeAlO was critical, as this method is accepted as the “gold standard” for plant-available P, but it is rarely used in commercial labs because of time and financial constraints. H3A-3 produced mean, median, standard deviations that are very similar to FeAlO strip results and low relative errors (2 > 0.96 with slopes 0.95 - 0.98). Although Mehlich 3 and water were correlated with FeAlO, Mehlich 3 (strongly acidic) extracted much more P than FeAlO, and water (low buffering capacity) extracted much less P across the range of soil pH values. Thus, H3A-3 provides an improved methodology to accurately determine plant-available P by mimicking root exudate action in the soil, while avoiding the time-consuming and costly FeAlO procedure. In the face of high-profile water quality impairments with enormous economic costs, such advancements are critical to balance agronomic production with environmental concerns.

关键词： Soil Testing Soil Extraction Soil Test Phosphorus

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