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A methodology for simulating 2d shock-induced dynamic stall at flight test-based fluctuating freestream

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Chinese Journal of Aeronautics 2019年第10期32卷 2223-2238页

作者： Khider AL-JABURI daniel FESZTY Fred NITZSCHE department of Mechanical and Aerospace Engineering Carleton University

A comprehensive methodology for simulating 2 d dynamic stall at fluctuating freestream is proposed in this paper.2 d CFd simulation of a SC1095 airfoil exposed to a fluctuating freestream of Mach number 0.537±0.205 and Reynolds number 6.1×10~6(based on the mean Mach number)and undergoing a 10°±10°pitch oscillation with a frequency of 4.25 Hz was *** conditions were selected to be representative of the flow experienced by a helicopter rotor airfoil section in a real-life fast forward *** constant freestream dynamic stall as well as fluctuating freestream dynamic stall simulations were conducted and *** methodology was carefully validated with experimental data for both transonic flow and dynamic stall under fluctuating ***,the results suggest that the fluctuating freestream alters the dynamic stall mechanism documented for constant freestream in a major way,emphasizing that inclusion of this effect in the prediction of dynamic stall related rotor loads is imperative for rotor performance analysis and blades design.

关键词： Mach fluctuation Pitching airfoil Shock-induced dynamic stall Transonic flow Unsteady freestream velocity

Phosphate-activated glutaminase activity is enhanced in brain, intestine and kidneys of rats following portacaval anastomosis

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World Journal of Gastroenterology 2006年第15期12卷 2406-2411页

作者： Manuel Romero-Gómez María Jover daniel díaz-Gómez Laura Collantes de Terán Regina Rodrigo Inés Camacho Miriam Echevarría Vicente Felipo Juan d Bautista Unit for the Clinical Management of digestive diseases Hospital Universitario de Valme SevillaSpain department of Biochemistry Bromatology and Toxicology Faculty of PharmacyUniversity of SevilleSpain Laboratory of Neurobiology Fundación Valenciana de Investigaciones Biomédicas ValenciaSpain Biochemistry Unit Hospital Universitario de Valme SevillaSpain Instituto de Investigaciones Biomédicas departament of Physiology University of SevilleSpain Laboratory of Neurobiology Fundación Valenciana de Investigaciones Biomédicas ValenciaSpain

AIM： To assess whether portacaval anastomosis （PCA） in rats affects the protein expression and/or activity of glutaminase in kidneys, intestines and in three brain areas of cortex, basal ganglia and cerebellum and to explain the neurological alterations found in hepatic encephalopathy （HE）. METHOdS： Sixteen male Wistar rats weighing 250-350 g were grouped into sham-operation control （n=8） or portacaval shunt （n = 8）. Twenty-eight days after the procedure, the animals were sacrificed. The duodenum, kidney and brain were removed, homogenised and mitochondria were isolated. Ammonia was measured in brain and blood. Phosphate-activated glutaminase （PAG） activity was determined by measuring ammonia production following incubation for one hour at 37 ℃ with O-phthalaldehyde （OPA） and specific activity expressed in units per gram of protein （pkat/g of protein）. Protein expression was measured by immunoblotting. RESULTS： duodenal and kidney PAG activities together with protein content were significantly higher in PCA group than in control or sham-operated rats （duodenum PAG activity was 976.95±268.87μkat/g of protein in PCA rats vs 429.19±126.92.μkat/g of protein in shamoperated rats; kidneys PAG activity was 1259.18±228.79 μkat/g protein in PCA rats vs 669.67±400.8 μkat/g of protein in controls, P〈0.05; duodenal protein content： 173% in PCA vs sham-operated rats; in kidneys the content of protein was 152% in PCA vs sham-operated rats）. PAG activity and protein expression in PCA rats were higher in cortex and basal ganglia than those in shamoperated rats （cortex： 6646.6 ±1870.4 μkat/g of protein vs 3573.8± 2037.4 μkat/g of protein in control rats, P〈 0.01; basal ganglia, PAG activity was 3657.3± 1469.6 μkat/g of protein in PCA rats vs 2271.2±384 μkat/g of protein in sham operated rats, P〈0.05; In the cerebellum, the PAG activity was 2471.6±701.4 μkat/g of protein vs 1452.9 ±567.8 μkat/g of protein in the PCA and sham rats, respectively, P〈0.05; content of protein： cerebral co

关键词： Hyperammonaemia Minimal hepaticencephalopathy Glutamine Protein content Shamoperated

distribution Control Centers in the US and Europe:Commonalities,differences,and Lessons

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Journal of Modern Power Systems and Clean Energy 2022年第2期10卷 259-268页

作者： Subramanian Vadari Izudin dzafic dan'l Koch Ryan Murphy daniel Hayes Jr. Tarik donlagic Modem Grid Solutions New YorkUSA University of Sarajevo Faculty of Electrical EngineeringSarajevoBosnia and Herzegovina R.Murphy are with Puget Sound Energy BellevueUSA Commonwealth Edison ChicagoUSA Siemens AG ErlanglenGermany

The distribution control center(dCC)has evolved from a sideshow in the traditional distribution service center to a major centerpiece of the utility moving into the decentralized ***,this is the place where much of the action is happening due to new forms of energy that are coining into the distribution *** creates the flexibility of operation and in-creased complexity due to the need for increased coordination between the transmission control center and ***,the US and European utilities have adapted to this change in very different ***,we describe the research works done in a dCC and their evolutions from the perspectives of major US utilities,and those enhanced by the European perspective focusing on the coordination of distribution system operator and transmission system operator(dSO-TSO).We pres-ent the insights into the systems used in these control centers and the role of vendors in their *** this paper,we present the perspectives of challenges,operational capabilities,and the involvement of various parties who will be re-sponsible to make the transition *** differences are pointed out on how distribution operations are conducted between the US and Europe.

关键词： distribution control center(dCC) power system operation distributed generation asset flexibility volt-var optimization and control.

Combating infectious diseases of poverty: a year on

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Infectious diseases of Poverty 2013年第1期2卷 224-230,223页

作者： Shang Xia Pascale Allotey daniel d Reidpath Pin Yang Hui-Feng Sheng Xiao-Nong Zhou National Institute of Parasitic diseases Chinese Center for Disease Control and Prevention(China CDC)Shanghai 200025People’s Republic of China WHO Collaborating Centre for Malaria Schistosomiasis and FilariasisKey Laboratory of Parasite&Vector BiologyMinistry of HealthShanghai 200025People’s Republic of China Jeffrey Cheah School of Medicine and Health Sciences Monash University Sunway CampusKuala LumpurMalaysia

The Infectious diseases of Poverty journal,launched a year ago,is a platform to engage outside the traditional disciplinary boundaries,and disseminate high quality science towards the improvement of *** paper reviews the milestone achievements during its first year of *** journal has filled an important niche,addressing some of the main priorities in the Global Report for Research on Infectious diseases of *** include the publication of three thematic issues on health systems,surveillance and response systems,as well as co-infection and *** thematic issues have foregrounded the importance and innovation that can be achieved through transdisciplinary *** journal has been indexed by PubMed since April 2013,with the publication of a total of 38 ***,the journal is delivering to wider range readers both in developing and developed countries with sustained efforts with a focus on relevant and strategic information towards elimination of infectious diseases of poverty.

关键词： Infectious diseases of poverty Health system Surveillance and response systems Coinfection Syndemics

diversity, Endemism and Conservation of Ferns(Polypodiales) in the Mexican Mountain Component

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Journal of Mountain Science 2015年第4期12卷 891-904页

作者： SANGINéS-FRANCO Celia LUNA-VEGA Isolda CONTRERAS-MEdINA Raúl ESPINOSA david TEJERO-díEZ José daniel RIVAS Gerardo Laboratorio de Biogeografía y Sistemática Departamento de Biología Evolutiva Facultad de Ciencias Universidad Nacional Autónoma de México (UNAM) Escuela de Ciencias Universidad Autónoma "Benito Juárez" de Oaxaca (UABJO) Av.Universidad s/n Ex Hacienda de Cinco Se?ores Oaxaca de Juárez CP 68120 Oaxaca México Facultad de Estudios Superiores Zaragoza Unidad Multidisciplinaria de Investigación Experimental ZaragozaUniversidad Nacional Autónoma de México (UNAM) Carrera de Biología Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de México MéxicoAvenida de los Barrios Número 1 Colonia Los Reyes Iztacala Tlalnepantla CP 54090 Estado de México México Laboratorio de Biogeografía Acuática Departamento de Biología Comparada Facultad de Ciencias Universidad Nacional Autónoma de México (UNAM)

We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices and richness and beta diversity *** data were obtained from several herbaria and specialized *** grid-cells appear to be important for fern species richness, as they contain 35 to 49 *** gridcells are located in the Sierra Madre Oriental(SMO),Trans-Mexican Volcanic Belt(TMVB) and the Sierra Madre del Sur(SMS).Mean richness by latitudinal belts of one degree showed that the belts with highest values are related to the TMVB and SMS.A total of 13grid-cells were recognized as important from theperspective of endemism; most of them are located also in the SMO, TMVB and *** richest gridcells coincided with one of the main centres of endemism for ferns obtained in this study, located in the convergence of the southern part of the SMO, the eastern portion of the TMVB and the northern part of the SMS, reflecting the high humidity existing on the mountain slopes facing the Gulf of *** important grid-cells recognized from richness and endemism analyses coincide with Mexican Natural Protected *** beta diversity analysis showed a low degree of similarity among grid-cells, implying a high species replacement, as the result of environmental heterogeneity occurring in the Mexican mountain *** the other hand, the spatial analysis suggested a pattern of phytogeographical regionalization comprising twomain areas: the Mexican Transition Zone and the Mexican Central *** play an important role in the Mexican biodiversity and contributing to the beta diversity of Mexico.

关键词： Biogeography distributional patterns Leptosporangiate ferns Mexico

A functional type I interferon pathway drives resistance to cornea herpes simplex virus type 1 infection by recruitment of leukocytes

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The Journal of Biomedical Research 2011年第2期25卷 111-119页

作者： Christopher d. Conrady Heather Jones Min Zheng daniel J.J. Carr departments of Microbiology Immunology The University of Oklahoma Health Science Center Oklahoma City OK 73104 USA departments of Ophthalmology The University of Oklahoma Health Science Center Oklahoma City OK 73104 USA

Type I interferons are critical antiviral cytokines produced following herpes simplex virus type-1 （HSV-1） infection that act to inhibit viral spread. In the present study, we identify HSV-infected and adjacent uninfected corneal epithelial cells as the source of interferon-a. We also report mice deficient in the A1 chain of the type I IFN receptor （Cdl18-/） are extremely sensitive to ocular infection with low doses （100 PFU） of HSV-1 as seen by significantly elevated viral titers in the cornea Compared to wild type （WT） controls. The enhanced susceptibil- ity correlated with a loss of Cd4＋ and Cd8＋ T cell recruitment and aberrant chemokine production in the cornea despite mounting an adaptive immune response in the draining mandibular lymph node of Cdll8/ mice. Taken together, these results highlight the importance of IFN production in both the innate immune response as well as eliciting chemokine production required to facilitate adaptive immune cell trafficking.

关键词： herpes simplex virus type 1 type I interferon comea viral infection leukocytes ocular immunology

A comparison of animal color measurements using a commercially available digital color sensor and photograph analysis

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Current Zoology 2020年第6期66卷 601-606页

作者： Alex d.Potash daniel U.Greene Gabrielle A.Foursa Verity L.Mathis L.Mike Conner Robert A.McCleery department of Wildlife Ecology and Conservation University of Florida Institute of Food and Agricultural ScienceGainesvilleFL 32611USA Weyerhaeuser Company Environmental Research SouthColumbusMS 39701USA department of Biology University of FloridaGainesvilleFL 32611USA Florida Museum of Natural History University of FloridaGainesvilleFL 32611USA The Jones Center at Ichauway NewtonGA 39870USA

An animal's pelage,feather,or skin color can serve a variety of functions,so it is important to have multiple standardized methods for measuring *** of the most common and reliable methods for measuring animal coloration is the use of standardized digital photographs of *** tech no logy in the form of a commercially available handheld digital color sensor could provide an alter native to photography-based animal color *** determine whether a digital color sensor could be used to measure animal coloration,we tested the ability of a digital color sensor to measure coloration of mammalian,avian,and lepidopteran museums *** compared results from the sensor to measurements taken using traditional photography *** study yielded significant differences between photography-based and digital color sensor measurements of brightness(light to dark)and colors along the green to red *** was no difference between photographs and the digital color sensor measurements for colors along the blue to yellow *** average difference in recorded color(AE)by the 2 methods was above the threshold at which humans can perceive a *** were sign讦icant correlations between the sensor and photographs for all measurements indicating that the sensor is an effective animal coloration measuring ***,the sensor's small aperture and narrow light spectrum range designed for human-vision limit its value for ecological *** discuss the conditions in which a digital color sensor can be an effective tool for measuring animal coloration in both laboratory settings and in the field.

关键词： animal coloration color measurement comparative method digital photography museum specimens Nix color sensor

Gas exchange of Populus euphratica leaves in a riparian zone

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Journal of Arid Land 2013年第4期5卷 531-541页

作者： dieter OVERdIECK daniel ZICHE Ruide YU Institute of Ecology/Ecology of Woody Plants TU-BerlinD-14195 BerlinGermany von Thuenen-Institut Institute of Forest Ecology and Forest InventoryD-16225 EberswaldeGermany Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

Riparian vegetation belts in arid regions of Central Asia are endangered to lose their ecosystem services due to intensified land *** the development of sustained land use,management knowledge of plant performance in relation to resource supply is *** estimated productivity related functional traits at the edges of the habitat of Populus euphratica *** leaf area （SLA） and carbon/nitrogen （C/N） ratio of *** leaves growing near a former river bank and close to moving sand dunes in the Ebinur Lake National Nature Reserve in Xinjiang,Northwest China （near Kazakhstan） were determined and daily courses of CO2 net assimilation （PN）,transpiration （E）,and stomatal conductance （gs） of two consecutive seasons were measured during July-August 2007 and June-July *** level was high （1.5-2.5 m below ground） throughout the years and no flooding occurred at the two tree *** was slightly lower near the desert than at the former river bank and leaves contained less N in relation to *** E and gs of *** were reached in the morning before noon on both stands and a second low maximum occurred in the afternoon despite of the unchanged high levels of air to leaf water vapor pressure deficit （ALVPd）.decline of gs in *** was followed by decrease of *** use efficiency （WUE） of leaves near the desert were higher in the morning and the evening,in contrast to leaves from the former river bank that maintained an almost stable level throughout the *** light compensation points and high light saturation levels of PN indicated the characteristics of leaves well-adapted to intensive irradiation at both *** general,leaves of *** decreased their gs beyond 20 Pa/kPa ALVPd in order to limit water *** of E did not occur in both stands until 40 Pa/kPa ALVPd was *** stomatal closure of *** was achieved at 60 Pa/kPa ALVPd in both stands.E through the leaf surface amounted up to 30％ of

关键词： Populus euphratica water vapor pressure deficit transpiration stomatal conductance water use efficiency leaf functional traits

The relationship between intraspecific assortative mating and reproductive isolation between divergent populations

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Current Zoology 2012年第3期58卷 484-492页

作者： daniel I. BOLNICK Mark KIRKPATRICK Howard Hughes Medical Institute and Section of Integrative Biology One University Station C0930 University of Texas at Austin Austin TX 78712 USA Section of Integrative Biology One University Station C0930 University of Texas at Austin Austin TX 78712 USA

The term ＇assortative mating＇ has been applied to describe two very different phenomena：（1） the tendency for indi- viduals to choose phenotypically similar mates from among conspecifics; or （2） the tendency to prefer conspecific over hete- rospecific mates （behavioral reproductive isolation）. Both forms of assortative mating are widespread in nature, but the relation- ship between these behaviors remains unclear. Namely, it is plausible that a preference for phenotypically similar conspecifics in cidentally reduces the probability of mating with phenotypically divergent heterospecifics. We present a model to calculate how the level of reproductive isolation depends on intraspecific assortative mating and the phenotypic divergence between species. For empirically reasonable levels of intraspecific assortment on a single trait axis, we show that strong reproductive isolation requires very substantial phenotypic divergence. We illustrate this point by applying our model to empirical data from threespine stickleback Gasterosteus aculeatus and darwin＇s Finches （Geospiza spp）. We conclude that typical levels of intraspecific assortment cannot generally be extrapolated to explain levels of interspecific reproductive isolation. Instead, reproductive isolation between species likely arises from different mate choice behaviors, or multivariate assortative mating [Current Zoology 58 （3）： 484-492, 2012].

关键词： Assortative mating Hybridization Mating preference Reproductive isolation Speciation