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THE BEHAVIOUR OF THE FLOW INVARIANTS OF LOCAL UNSTEADY HOMOGENEOUS SHEAR FLOW

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Journal of Hydrodynamics 1994年第3期6卷 25-33页

作者： allen T.Chwang Department of Mechanical Engineering University of Hong KongHong Kong

In this paper the vorticity equation and the rate- of- swain tensor equation of unsteady homogeneous shear flow of an incompressible fluid are investigated and five scalar invariants, such as enstrophy, etc. , equations are obtained. Then according to these scalar invariants equations and a pressure distribution assumption, the stability of the solution and its special behaviours are discussed. It is found out that under certain conditions the enstrophy and the second invariant of the rate-of-strain tensor will approach to infinity periodically. It is so-called blow up phenomenon and has the close relation with the burst phenomenon.

关键词： vorticity invariant blow up.

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Assimilation of atmospheric infrared sounder radiances with WRF-GSI for improving typhoon forecast

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Frontiers of Earth Science 2018年第3期12卷 457-467页

作者： Yan-An LIU Zhibin SUN Maosi CHEN Hung-Lung allen HUANG Wei GAO Key Laboratory of Geographic Information Science (Ministry of Education) East China Normal University Shanghai 200241 China School of Geographic Sciences East China Normal University Shanghai 200241 China ECNU-CSU Joint Research Institute for New Energy and the Environment East China Normal University Shanghai 200062 China Joint Laboratory for Environmental Remote Sensing and Data Assimilation East China Normal University Shanghai 200241 China Natural Resource Ecology Laboratory Colorado State University Fort Collins CO 80523 United States Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-Madison Madison WI 53706 United States

The Atmospheric Infrared Sounder （AIRS） can provide the profile information on atmospheric temperature and humidity in high vertical resolution. The assimilation of its radiances has been proven to improve the Numerical Weather Prediction （NWP） in global models. In this study, regional assimilation of AIRS radiances was carried out in a community assimilation system, using Gridpoint Statistical Interpolation （GSI） coupled with the Weather Research and Forecasting （WRY） model. The AIRS channel selection, quality control, and radiances bias correction were examined and illustrated for optimized assimilation. The bias correction scheme in the regional model showed that corrections on most of the channels produce satisfactory results except for several land surface channels. The assimilation and forecast experiments were carried out for three typhoon cases （Saola, Damrey, and Haikui in 2012） with and without including AIRS radiances. Results show that the assimilation of AIRS radiances into the WRF/GSI model improves both the typhoon track and intensity in a 72-hour forecast.

关键词： AIRS WRF/GSI model radiance assimilation typhoon forecast

Provision,transport and deposition of debris in urban waterways

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International Journal of Sediment Research 2015年第2期30卷 142-149页

作者： Deonie allen Scott Arthur Nicolas Wallerstien Janice Blanc Heather Haynes Heriot-Watt University

The transport of woody debris from urban surfaces,through local urban waterways,to constriction and blockage risk locations is not well *** trials have identified debris and watercourse dimensions as influential factors on debris movement,and large woody debris movement has been traced in the natural rural environment using time series photography,active transponders,and field *** novel passive transponder technology,small woody debris has been traced through an urban case study watercourse to establish key influential factors on urban debris *** incorporating urban debris transport detail into the source and deposition process,a complete picture of urban debris transport can be created,supporting effective culvert and trash screen design,watercourse maintenance and blockage risk *** case study highlights that factors beyond watercourse depth and velocity are influential in debris movement within an urban *** dimension and source location upstream are shown to significantly affect the potential for debris to reach a downstream constriction,illustrating a possible distance limitation in nuisance flow debris blockage risk.

关键词： Urban debris transport Flood risk Blockage Urban gross pollutants Passive integrated transponder technology

Jejunoileal bypass:A surgery of the past and a review of its complications

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World Journal of Gastroenterology 2009年第18期15卷 2277-2279页

作者： Dushyant Singh Alexandra S Laya Wendell K Clarkston Mark J allen Department of Gastroenterology and Hepatology University of Missouri Kansas CityKansas City MO 64111United States

Jejunoileal bypass(JIB),popular in the 1960s and 1970s,had remarkable success in achieving weight loss by creating a surgical short bowel *** patient had an unusual case of liver disease and provided no history of prior bariatric ***,it was recognized that he had a JIB in the 1970s,which was also responsible for the gamut of his *** with JIB are often not recognized,as they died of complications,or underwent reversal of their surgery or a liver-kidney *** identification with prompt reversal,and the recognition and treatment of the life-threatening consequences play a critical role in the management of such patients.

关键词： Jejunoileal bypass Bariatric surgery Weightloss Obesity Morbid obesity

Dynamics and mechanisms of permethrin resistance in a field population of the horn fly, Haematobia irritans irritans

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Insect Science 2009年第2期16卷 175-184页

作者： Andrew Y. Li Kimberly H. Lohmeyer J. allen Miller USDA ARS Knipling-Bushland US Livestock Insects Research Laboratory 2700 Fredericksburg Road Kerrville TX 78028 USA

A study was conducted at the Pressler ranch, near Kerrville, Texas, USA between 2002 and 2006 to determine the dynamics and mechanisms of resistance to permethrin in a field population of the horn fly, Haematobia irritans irritans （L.）. Changes of resistance to pyrethroid insecticide associated with use of a pour-on formulation of cyfluthrin in 2002 and use of diazinon ear tags in subsequent years were studied using a filter paper bioassay technique and a polymerase chain reaction assay that detects two sodium channel mutations, kdr and super-kdr resistance alleles. A maximum of 294-fold resistance to permethrin was observed in the summer of 2002. A significant decrease in the resistance level was observed in spring 2003, and resistance continued to decline after animals were treated with diazinon ear tags. In response to pyrethroid treatments, the allelic kdr and super-kdr frequency increased from 56.3% to 93.8% and from 7.5% to 43.8%, respectively in 2002, and decreased significantly in 2003 when the pyrethroid insecticide was no longer used to treat animals. Females were found to have a higher allelic super-kdr frequency than males in 2002, while no difference was detected between males and females in the allelic kdr frequency. There was a significant positive correlation between frequencies of the sodium channel mutations and levels ofpermethrin resistance, suggesting that the sodium channel mutations, kdr and super-kdr, are the major mechanisms of resistance to pyrethroids in this horn fly population. Results of synergist bioassays also indicated possible contributions of two metabolic detoxification mechanisms, the mixed function oxidases （MFO） and glutathione S-trans- ferases （GST）. Compared to a horn fly infestation of an untreated herd, treatments with the pyrethroid pour-on formulation failed to control horn flies at the Pressler ranch in 2002. Sustained control of horn flies was achieved with the use of diazinon ear tags in 2003 and subsequent years.

关键词： efficacy horn fly insecticide resistance PCR permethrin pyrethroids

Different paths to sexual size dimorphism in two praying mantids, Pseudomantis albofimbriata and Hierodula majuscula

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Insect Science 2014年第2期21卷 227-233页

作者： Louise E. allen Katherine L. Barry Gregory I. Holwell Department of Biological Sciences Macquarie University North Ryde NSW 2109 Australia School of Biological Sciences The University of Auckland Auckland New Zealand

Sexual size dimorphism （SSD） is widespread among diverse animal taxa and has attracted the attention of evolutionary biologists for over a century. SSD is likely to be adaptive and the result of divergent selection on different size optima for males and females, given their different roles in reproduction. The developmental trajectory leading to SSD may help us to understand how selection acts on male and female size. Here, we describe the growth and development of two Australian praying mantids, Pseudomantis albofimbriata and Hierodula majuscula including the number of moults, time to adulthood, size at each moult, and the degree of SSD. While both species exhibit the common pattern of female-biased SSD, the number of moults required for individuals to reach adulthood differed between males and females and between species. Despite their larger adult size, P. albofimbriata females require fewer moults and less time than males to reach adulthood, but are significantly larger than males from the second instar onwards. In contrast, H. majuscula males reached adulthood in fewer moults, and less time than females, however males and females did not differ in size until females went through their final moult into adulthood. H. majuscula also required more time and more moults to reach adulthood than 17. albofimbriata. We discuss these different developmental pathways in light of the existing knowledge of reproductive biology for each species. We also suggest that these differences may relate to the different phenologies that occur in strongly seasonal temperate environments compared with those in the tropics. This study provides evidence that SSD can result from two different patterns of growth and development in closely related species.

关键词： developmental trajectories Mantodea sexual size dimorphism

High throughput RNA sequencing utility for diagnosis and prognosis in colon diseases

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World Journal of Gastroenterology 2017年第16期23卷 2819-2825页

作者： Mamie Gao allen Zhong Neil Patel Chiraag Alur Dinesh Vyas Department of Surgery Texas Tech UniversityOdessaTX 79763United States

RNA sequencing is the use of hight hroughput next generation sequencing technology to survey, characterize, and quantify the transcriptome of a genome. RNA sequencing has been used to analyze the pathogenesis of several malignancies such melanoma, lung cancer, and colorectal cancer. RNA sequencing can identify differential expression of genes(DEG's), mutated genes, fusion genes, and gene isoforms in disease states. RNA sequencing has been used in the investigation of several colorectal diseases such as colorectal cancer, inflammatory bowel disease(ulcerative colitis and Crohn's disease), and irritable bowel syndrome.

关键词： Colon RNA sequencing Colon cancer Transcriptome Next generation sequencing high throughput

Expression of octopaminergic receptor genes in 4 nonneural tissues in female Nicrophorus vespilloides beetles

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Insect Science 2015年第4期22卷 495-502页

作者： Christopher B. Cunningham Mary K. Douthit allen J. Moore Department of Genetics University of Georgia Athens GA 30602 USA

Octopamine regulates the function of many tissues and physiological processes in invertebrates. The expression of octopamine receptor genes has been examined in multiple tissue types in several different insect orders. However, little work has addressed this issue in Coleoptera. Most studies characterize individual genes in different tissue types, but here we describe the expression of 6 octopamine receptor genes in thoracic musculature, oviducts, Malpighian tubules, and fat body of female Nicrophorus vespilloides beetles to characterize both different genes and different tissues within a single study. We then compare the gene expression profiles found in this beetle to other insects to examine the extent to which expression profiles are conserved across insects. We also examine the relative involvement of octopamine verses octopamine/tyramine receptors based on receptor gene expression in each tissue to help elucidate if tyramine plays a role in the regulation of these tissues. We find a high degree of overlap in the expression profile of the 6 genes examined in the thoracic muscula^tre, a moderate amount for the oviducts, and divergent profiles for Malpighian tubules and fat body. Based on expression difference in receptor subtypes, our results also support the suggestion that tyramine is a biogenic amine with physiological actions separate from octopamine.

关键词： biogenic amines Coleoptera G-protein coupled receptors quantitative real-time PCR

Driving efficiency in a high-throughput metabolic stability assay through a generic high-resolution accurate mass method and automated data mining

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Protein & Cell 2011年第8期2卷 680-688页

作者： Wenqing Shui Song Lin allen Zhang Yan Chen Yingying Huang Mark Sanders College of Life Sciences Nankai UniversityTianjin 300071China High-Throughput Molecular Drug Discovery Center Tianjin Joint Academy of Biotechnology and MedicineTianjin 300074China Metabolism&Pharmacokinetics NovartisEmeryvilleCA 94608USA Thermo Fisher Scientific San JoseCA 95134USA

Improving analytical throughput is the focus of many quantitative workflows being developed for early drug *** drug candidate screening,it is common practice to use ultra-high performance liquid chromatography(U-HPLC)coupled with triple quadrupole mass *** approach certainly results in short analytical run time;however,in assessing the true throughput,all aspects of the workflow needs to be considered,including instrument optimization and the necessity to re-run samples when information is *** we describe a high-throughput metabolic stability assay with a simplified instrument set-up which significantly improves the overall assay *** addition,as the data is acquired in a non-biased manner,high information content of both the parent compound and metabolites is gathered at the same time to facilitate the decision of which compounds to proceed through the drug discovery pipeline.

关键词： metabolic stability high-resolution mass spectrometry accurate mass ultra-high performance liquid chromatography

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