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On local Singularities in Ideal Potential Flows with Free Surface

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Chinese Annals of Mathematics,Series B 2019年第6期40卷 925-948页

作者： Jian-Guo lIU robert l.PEGO Department of Physics and Department of Mathematics Duke UniversityDurhamNC 27708USA Department of Mathematical Sciences and Center for Nonlinear Analysis Carnegie Mellon UniversityPittsburghPennsylvaniaPA 12513USA

Despite important advances in the mathematical analysis of the Euler equations for water waves,especially over the last two decades,it is not yet known whether local singularities can develop from smooth data in well-posed initial value *** ideal free-surface flow with zero surface tension and gravity,the authors review existing works that describe"splash singularities",singular hyperbolic solutions related to jet formation and"flip-through",and a recent construction of a singular free surface by Zubarev and Karabut that however involves unbounded negative *** authors illustrate some of these phenomena with numerical computations of 2D flow based upon a conformal mapping *** tests with a different kind of initial data suggest the possibility that corner singularities may form in an unstable way from specially prepared initial data.

关键词： Incompressible flow Water wave equations Splash singularity Flipthrough Dirichlet hyperbolas Conformal mapping

Discharge-Stage Relationship on Urban Streams Evaluated at USGS Gauging Stations,***,Missouri

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Journal of Earth Science 2020年第6期31卷 1133-1141页

作者： robert E.Criss David l.Nelson Department of Earth and Planetary Sciences Washington UniversitySt.Louis MO 63130USA Columbia Cir Pasadena CA 91105USA

Extensive USGS data tables and detailed,1 m2 li DAR surveys are used to determine the optimal power n that relates discharge(Q)to stage(h*)above channel bottom(ho)at 39 gauging stations on small streams in the ***,Missouri area,all of which have catchments of 0.6 to 220 *** different methodologies are employed to determine both n and ho:(1)optimizing linearity in a plot of Q1/n *** stage(hl)using USGS field measurements at each site;(2)optimizing linearity in a plot of Q1/n *** using USGS rating tables at each site;(3)a mathematical inverse method applied to the same USGS rating tables;(4)use of li DAR data on channel geometry to determine the power dependences of channel area A and hydraulic radius H on h*,combined with the Manning and rational equations to predict *** these methods,only methods 2 and 3 compare favorably,and these values compare poorly with Method 1 based on field data,and with method 4 based on theoretical and empirical *** Method 4 is predictive,it provides a useful alternative to methods 1–3 that are based on USGS field measurements,which are heavily weighted toward low *** conclude that the apparent values of n in the USGS rating tables are systematically too low for small streams.

关键词： stream gauging li DAR topography urban flooding discharge hydrology

Seismic interferometry and estimation of the Green's function using Gaussian beams

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Earthquake Science 2010年第5期23卷 417-424页

作者： robert l. Nowack Department of Earth and Atmospheric Sciences Purdue University

This study investigates seismic interferometry in which the Green＇s function is estimated between two receiv- ers by cross-correlation and integration over sources. For smoothly varying source strengths, the dominant contributions of the correlation integral come from the stationary phase directions in the forward and backward directions from the alignment of the two receivers. Gaussian beams can be used to evaluate the correlation integral and concentrate the amplitudes in a vicinity of the stationary phase regions instead of completely relying on phase interference. Several numerical examples are shown to illustrate how this process works. The use of Gaussian beams for the evaluation of the correlation integral results in stable estimates, and also provides physical insight into the estimation of the Green＇s function based on seismic interferometry.

关键词： seismic interferometry Gaussian beams Green's function

High diversity of Graphidaceae (lichenized Ascomycota: Ostropales) in Amazonian Perú

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Fungal Diversity 2013年第1期58卷 13-32页

作者： Eimy Rivas Plata robert lücking Department of Biological Sciences University of Illinois-Chicago845 West Taylor Street(MC 066)ChicagoIL 60607USA Department of Botany The Field Museum1400 South Lake Shore DriveChicagoIL 60605-2496USA

A survey of crustose microlichens at los Amigos Biological Station in Amazonian Peru revealed 116 species of Graphidaceae at this *** is the second highest number of Graphidaceae ever reported for a single site world-wide,after the Surumoni crane station in Venezuela,with 131 species,and followed by Fakahatchee Strand Park Preserve in Florida,with 111 *** on the number of Graphidaceae found at los Amigos,we predict the total lichen species richness at this site to be approximately 700 *** the 116 species encountered at los Amigos,59 were graphidoid species(former Graphidaceae ***.)and 67 thelotremoid species(former Thelotremataceae).The following 18 species are described as new:Ampliotrema sorediatum Rivas Plata&lücking,***,Chapsa hypoconstictica Rivas Plata&lücking,***,Chapsa scabiocarpa Rivas Plata&lücking,***,Chapsa subsorediata Rivas Plata&lücking,***,Diorygma nigricans Rivas Plata&lücking,***,Fissurina flavomedullosa Rivas Plata&lücking,***,Fissurina platythecioides Rivas Plata&lücking,***,Graphis apertoinspersa Rivas Plata&lücking,***,Graphis pitmanii Rivas Plata&lücking,***,leucodecton inspersum Rivas Plata&lücking,***,Ocellularia cicra Rivas Plata&lücking,***,Ocellularia fenestrata Rivas Plata&lücking,***,Ocellularia microsorediata Rivas Plata&lücking,***,Ocellularia natashae Rivas Plata&lücking,***,Ocellularia plicata Rivas Plata&lücking,***,Ocellularia protoinspersa Rivas Plata&lücking,***,Ocellularia pustulata Rivas Plata&lücking,***,and Thelotrema amazonicum Rivas Plata&lücking,***.

关键词： lichens Thelotremoid Tropical Rainforest Corticolous Madre de Dios

Osteoarticular lesions of the Shoulder Girdle by Hippopotamus Bite: Highly Septic lesion

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Open Journal of Orthopedics 2024年第2期14卷 114-121页

作者： Jr Pierre Germain Ochou Achié Jean Régis Akobe Yao Aboh Ganyn robert Arnaud Assere Kouamé Jean-Eric Kouassi Adelaïde Aya Natacha Kouassi Ibrahim Soumahoro Zolopégué Marcel Soro Sédi loues De Randolphe Akpro Gbalé Yannick Blé Kouamé Innocent M’bra loukou Blaise Yao Bada Juste léopold NiaoréSery Koffi léopold Krah Michel Kodo Department of Orthopaedic and Traumatological Surgery Bouaké University Hospital Bouaké Ivory Coast Raoul Follereau Institute Manikro Centre Bouaké Ivory Coast

Hippopotamus bites are rare in medical consultations, despite several studies exposing their aggressive character. A case of a hippopotamus bite on the shoulder of a fisherman has been reported. In addition to the osteoarticular aspect representing a therapeutic problem, the infectious aspect was marked by sepsis, with a death in less than 48 hours. Based on this observation, a protocol for the initial management of large animal bites was submitted.

关键词： Bite Hippopotamus Septic Shock

Neuromelanin,one of the most overlooked molecules in modern medicine,is not a spectator

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Neural Regeneration Research 2017年第3期12卷 372-375页

作者： robert l.Haining Cindy Achat-Mendes Georgia Gwinnett College 1000 University Center LnSchool of Science and TechnologyLawrencevilleGAUSA

The loss of pigmented neurons from the human brain has long been the hallmark of Parkinson＇s disease（PD）.Neuromelanin（NM） in the pre-synaptic terminal of dopamine neurons is emerging as a primary player in the etiology of neurodegenerative disorders including *** mini-review discusses the interactions between neuromelanin and different molecules in the synaptic terminal and describes how these interactions might affect neurodegenerative disorders including *** can reversibly bind and interact with amine containing neurotoxins,e.g.,MPTP,to augment their actions in the terminal,eventually leading to the instability and degeneration of melanin-containing neurons due to oxidative stress and mitochondrial *** particular,neuromelanin appears to confer susceptibility to chemical toxicity by providing a large sink of iron-bound,heme-like structures in a pi-conjugated system,a system seemingly purposed to allow for stabilizing interactions including pi-stacking as well as ligand binding to *** the progressive accumulation of NM with age corresponding with an apparent decrease in dopamine synthetic pathways,the immediate question of whether NM is also capable of binding dopamine,the primary functional monoamine utilized in this cell,should be *** the rather glaring implications of this finding,this idea appears not to have been adequately *** such,we postulate on potential mechanisms by which dopamine might dissociate from neuromelanin and the implications of such a reversible ***,if neuromelanin is able to sequester and release dopamine in membrane bound vesicles,this intracellular pre-synaptic mechanism could be the basis for a form of chemical memory in dopamine neurons.

关键词： dopamine dopamine storage Parkinson's disease neurodegeneration neuromelanin neurotoxicity

landform type mediates compositional change in a hurricane-disturbed subtropical forest

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Ecological Processes 2020年第1期9卷 292-304页

作者： robert l.Spicer Ariel Elugo Nathan Ruhl Department of Biological Science Rowan UniversityGlassboroNJ 08028USA International Institute of Tropical Forestry United States Department of Agriculture Forest ServiceJardín Botánico SurRío PiedrasPRUSA

Background:Categorization of topographical features into landform type is a long-standing method for understanding physiographic patterns in the *** in forest composition between landform types are driven primarily by concurrent differences in soil composition and moisture,but also disturbance *** studies have focused on the interaction between fire disturbance,succession,and landforms,but the effects of hurricane disturbance on compositional differences between landforms are poorly *** the study presented here,we assess compositional and structural differences between landform types in the tree community of a young sub-tropical forest that is frequently subjected to ***,we ask whether the tree community(1)changed structurally over the study period,(2)experienced compositional change over the study period,(3)is compositionally different between landform types,and(4)exhibits compositional change mediated by landform ***:The tree community experienced significant structural change over the course of our study,but compositional change was only significant for some ***:Despite large-scale,intense,and frequent hurricane disturbance to our study system,compositional change in the tree community was localized and only significant for some landform types.

关键词： Hurricane Forest Community Composition Change Succession landform

Update on obesity surgery

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World Journal of Gastroenterology 2006年第20期12卷 3196-3203页

作者： Dan Eisenberg Andrew J Duffy robert l Bell Department of Surgery Yale University School of Medicine 40 Temple St. Suite 3A New HavenCT 06510United States

The prevalence of obesity in the United States has reached epidemic proportions. With more than 30 million Americans clinically obese, the younger population has also been affected. Surgical therapy should be offered to the severely obese patient who is refractory to nonsurgical therapy, as established by the 1991 NIH Consensus Conference on Gastrointestinal Surgery for Severe Obesity. Surgery is currently the most effective therapy for weight loss. It is far more effective than any other treatment modality, both in terms of the amount of weight loss and in terms of durability in maintaining weight loss.

关键词： Obesity Gastrointestinal surgery Roux-Y gastric bypass

Different characteristics of chronic dibutyltin dichloride-induced pancreatitis and cholangitis in mouse and rat

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Hepatobiliary & Pancreatic Diseases International 2020年第2期19卷 169-174页

作者： Friederike lütt luise Ehlers Horst Nizze robert Jaster Department of Medicine II Division of GastroenterologyRostock University Medical CenterE.-Heydemann-Str.618057 RostockGermany Institute of Pathology Rostock University Medical CenterStrempelstraβ1418057 RostockGermany

Background:Current animal models of chronic pancreatitis(CP)often provide only limited pathophysio-logical insights since they incompletely reflect the human *** induced by injection of dibutyltin dichloride(DBTC-pancreatitis)shares with human CP the important feature of extended fibrosis and would be an even more attractive model if it could be transferred from rats to mice,as recently sug-gested in the context of combined ethanol and DBTC *** study aimed to evaluate the effects of DBTC in pancreas and liver of C57Bl/6 mice,a strain commonly used to engineer genetic mouse ***:C57Bl/6 mice and lewis rats were exposed to variable doses of *** an investigation period of up to 4 weeks,laboratory findings and histopathological changes of pancreas and liver were ***:Chronic DBTC-pancreatitis in rats was characterized by acinar cell damage,ductal changes,fi-brosis,and inflammatory cell *** treated with DBTC at 6–8 mg/kg body weight,the standard doses in rats,showed transient increases of lipase activities but no morphological signs of chronic DBTC-pancreatitis 4 weeks after injection of the *** doses of 10–12 mg/kg DBTC were intolerable due to their high *** contrast,mice and rats presented with a similar histopathology of the liver that can be characterized as a chronic-proliferative DBTC-cholangitis with predominating damage and proliferation of the small bile ducts as well as secondary portal inflammatory cell infiltrates and a begin-ning portal ***:The DBTC-model cannot be transferred from rats to C57Bl/6 mice with respect to chronic DBTC-pancreatitis,but might be of interest to study DBTC-cholangitis in both species.

关键词： Animal models Cholangitis Pancreatitis