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River Management and Flooding: The Lesson of December 2015–January 2016, Central USA

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Journal of earth Science 2016年第1期27卷 117-122页

作者： robert e.Criss Mingming Luo Department of earth and Planetary Sciences Washington University in St.Louis School of environmental Studies China University of Geosciences

The huge winter storm of December 23-29, 2015 delivered heavy rainfall in a broad swath across the USA, deluging east-Central Missouri. Record high river levels were set at many sites, but damages were most pronounced in developed floodplain areas, particularly where high levees were built or river channels greatly narrowed. An average of 20 cm of rain that mostly fell in three days impacted the entire 10 300 km2 Meramec Basin. Compared to the prior record flood of 1982, the highest relative stage（＋1.3 m） on Meramec River occurred at Valley Park proximal to（1） a new levee,（2） a landfill in the floodway,（3） large floodplain construction fills, and（4） tributary creek basins impacted by suburban sprawl. even though only a small fraction of the 1.8 million km2 Mississippi River watershed above St. Louis received extraordinary rainfall during this event, the huge channelized river near and below St. Louis rapidly rose to set the 3rd-highest to the highest stages ever, exhibiting the flashy response typical of a much smaller river.

关键词： floods Mississippi River levees floodplain development.

effect of losing a fight on later agonistic behavior toward unfamiliar conspecifics in male Syrian hamsters

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Current Zoology 2011年第4期57卷 449-452页

作者： Javier DeLBARCO-TRILLO robert e. JOHNSTON Comell University Department of Psychology Uris Hall Ithaca NY 14853 USA

In many species, agonistic interactions result in social relationships that are stable over time. In Syrian hamsters, two unfamiliar males that are placed together will fight vigorously and a clear winner/loser relationship is usually established. In subsequent interactions, the loser will flee soon after detecting the familiar winner. Here we tested the hypothesis that losing a fight with a conspecific will affect future agonistic interactions not only toward that individual （i.e., the familiar winner） but also toward unfamiliar conspecifics. To test this hypothesis we paired two Syrian hamster males in three trials on one day in which the loser had tile opportunity to escape the winner. The next day the loser was paired with an unfarniliar male, also for three trials. If he lost again, he was tested on a third day with a third unfamiliar male. Subjects were those males that were losers on all three days. The latency to escape on the first trial on Days 2 and 3 was significantly shorter than on the first trial on Day l, indicating that losing against the first male affected the response toward unfamiliar males. However, the latency to escape on the first trial on Days 2 and 3 was significantly longer than that on the third trial on the preceding day, indicating that a loser treats unfamiliar males differently than a familiar winner. These results suggest that a defeat during an interaction with one male affects later agonistic behavior towards other, unfamiliar males [Current Zoology 57 （4）： 449-452, 2011].

关键词： Agonistic behavior Loser Hamsters Mesocricetus

The impact of macroalgae on mean and turbulent flow fields

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Journal of Hydrodynamics 2015年第3期27卷 427-435页

作者： THOMAS robert e. MCLeLLAND Stuart J. Department of Geography Environment and Earth Sciences University of Hull

In this paper, we attempt to quantify the mean and turbulent flow fields around live macroalgae within a tidal inlet in Norway. Two Laminaria digitata specimens - 0.50 m apart were selected for detailed study and a profiling ADV was used to collect 45 velocity profiles, each composed of up to seven 0.035 m-high profiles collected for 240 s at 100 Hz, at a streamwise spacing of 0.25 m and cross-stream spacing of 0.20 m. To quantify the impact of the macroalgae, measurements were repeated over a sparser grid after the region had been completely cleared of algae and major roughness elements.

关键词： dealiasing laminaria digitata turbulence vectrino profiler velocity profile

Recent trends in the surgical management of inflammatory bowel disease

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World Journal of Gastroenterology 2008年第3期14卷 408-412页

作者： robert e Roses John L Rombeau University of Pennsylvania School of Medicine Philadelphia Pennsylvania Temple University School of Medicine Philadelphia Pennsylvania United States

Surgery is required in the vast majority of patients with Crohn’s disease (CD) and in approximately one-third of patients with ulcerative colitis (UC). Similar to medical treatments for IBD, significant advances have occurred in surgery. Advances in CD include an emphasis upon conservatism as exemplified by more limited resections, strictureplasties, and laparoscopic resections. The use of probiotics in selected patients has improved the outcome in patients with pouchitis following restorative proctocolectomy for UC. It is anticipated that ongoing discoveries in the molecular basis of IBD will in turn identify those patients who will best respond to surgery.

关键词： Crohn's disease Ulcerative colitis Ileal pouchanal anastomosis Laparoscopic colectomy

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

Cardiac troponins in the elderly:interpretation of elevated levels

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Journal of Geriatric Cardiology 2007年第3期4卷 188-192页

作者： robert e Fromm Baylor College of Medicine Senior IntensivistVISICUinc. 2219 Dorrington Street HoustonTX 77030USA Jr

elderly patients with myocardial infarction commonly present with symptoms other than chest pain. The clinician evaluation of the elderly may rely on laboratory methods more so than in younger patients. Fortunately,advances in laboratory science have brought newer biomarkers of cardiac injury to the clinical arena including cardiac troponins I and T(cTnI,cTnT) . These regulatory components of the contractile apparatus are sensitive indicators of myocardial injury. Their central role in the current definition of acute myocardial infarction highlights their utility in the diagnosis of acute myocardial ischemic syndromes. The troponins are also released in some clinical situations where thrombotic complications of coronary artery disease and resultant acute myocardial infarction have not occurred. examples of these conditions include conditions like myocarditis,pulmonary embolism,sepsis,and acute stroke. elevated troponins in these conditions are thought to emanate from injured myocardial cells and in most circumstances have been associated with adverse outcomes. Interpretation of elevated troponin in the elderly requires consideration of other possible conditions.

关键词： acute myocardial infarction thrombolysis elderly

experimental analysis of tip vortex cavitation mitigation by controlled surface roughness

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Journal of Hydrodynamics 2020年第6期32卷 1059-1070页

作者： Urban Svennberg Abolfazl Asnaghi robert Gustafsson Rickard e.Bensow Kongsberg Hydrodynamic Research Centre Kongsberg Maritime ABKristinehamnSweden Department of Mechanics and Maritime Sciences Chalmers University of TechnologyGothenburgSweden

This study presents results of experiments where roughness applications are evaluated in delaying the tip vortex cavitation inception of an elliptical ***-speed video recordings and laser doppler velocimetry(LDV)measurements are employed to provide further details on the cavitation behavior and tip vortex flow properties in different roughness pattern *** angular momentum measurements of the vortex core region at one chord length downstream of the tip indicate that roughness leads to a lower angular momentum compared with the smooth foil condition while the vortex core radius remains similar in the smooth and roughened *** observations show that the cavitation number for tip vortex cavitation inception is reduced by 33%in the optimized roughness pattern compared with the smooth foil condition where the drag force increase is observed to be around 2%.During the tests,no obvious differences in the cavitation inception properties of uniform and non-uniform roughness distributions are ***,the drag force is found to be higher with a non-uniform roughness distribution.

关键词： Roughness tip vortex mitigation cavitation suppression

Covering Your Bases： Inheritance of DNA Methylation in Plant Genomes

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Molecular Plant 2014年第3期7卷 472-480页

作者： Chad e. Niederhuth robert J. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA

Cytosine methylation is an important base modification that is inherited across mitotic and meiotic cell divisions in plant genomes. Heritable methylation variants can contribute to within-species phenotypic variation. Few methylation variants were known until recently, making it possible to begin to address major unanswered questions： the extent of natural methylation variation within plant genomes, its effects on phenotypic variation, its degree of depend- ence on genotype, and how it fits into an evolutionary context. Techniques like whole-genome bisulfite sequencing （WGBS） make it possible to determine cytosine methylation states at single-base resolution across entire genomes and populations. Application of this method to natural and novel experimental populations is revealing answers to these long-standing questions about the role of DNA methylation in plant genomes.

关键词： DNA methylation epigenetics epiallele whole-genome bisulfite sequencing.

evaluation of the Heat,entropy,and Rotational Changes Produced by Gravitational Segregation during Core Formation

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Journal of earth Science 2015年第1期26卷 124-133页

作者： Anne M.Hofmeister robert e.Criss Department of earth and Planetary Sciences Washington University

Core formation by gravitational segregation allegedly released sufficient interior heat to melt the earth. Analysis of the energetics, which compare gravitational potential energy （Ug） of a fictitious, homogeneous reference state to earth＇s current layered configuration, needs updating to correct errors and omissions, and to accommodate recent findings：（1） An erroneous positive sign was used for Ug while maintaining the reference value of 0 at infinity, which results in an incorrect sign fur AUg, which is crucial in determining whether a process is endothermic or exothermic. （2） The value of Ug for earth＇s initial state is uncertain. （3） Recent meteorite evidence indicates that core formation began before the earth was full-sized, which severely limits AUg. （4） Inhomogeneous accretion additionally reduced AUg. （5） The potentially large effect of differential rotation between the core and the mantle was not accounted for. （6） entropy changes associated with creating order were neglected. Accordingly, we revise values of Ug, evaluate uncertainties, and show that AUg was converted substantially to eonfigurational energy （TAS）. These considerations limit the large sources of primordial heat to impacts and radioactivity. Although these processes may play a role in core formation, their energies are independent of gravitational segregation, which produces order and rotational energy, not internal heat. Instead, gravitational segregation promotes planetary cooling mainly because it segregates lithophilic radioactive elements upward, increasing surface heat flux while shortening the distance over which radiogenic heat diffuses outwards.

关键词： core formation primordial heat configurational energy thermodynamics rotational energy.