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Numerical investigation of entropy generation and heat transfer of pulsating flow in a horizontal channel with an open cavity

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Journal of Hydrodynamics 2017年第4期29卷 632-646页

作者： Fatma Zamzari Zouhaier Mehrez Afif El cafsi Ali Belghith Patrick Le Quéré Faculty of Sciences of Tunis Laboratory of Energy Heat and Mass Transfer (LETTM) Department of Physics El Manar University Computer Science Laboratory for Mechanics and Engineering Sciences (LIMSI)

In this study, the entropy generation and the heat transfer of pulsating air flow in a horizontal channel with an open cavity heated from below with uniform temperature distribution are numerically investigated. A numerical method based on finite volume method is used to discretize the governing equations. At the inlet of the channel, pulsating velocity is imposed for a range of Strouhal numbers Stpfrom 0 to 1 and amplitude Apfrom 0 to 0.5. The effects of the governing parameters, such as frequency and amplitude of the pulsation, richardson number, ri, and aspect ratio of the cavity, L/H, on the flow field, temperature distribution, average Nusselt number and average entropy generation, are numerically analyzed. The results indicate that the heat transfer and entropy generation are strongly affected by the frequency and amplitude of the pulsation and this depends on the richardson number and aspect ratio of the cavity. The pulsation is more effective with the aspect ratio of the cavity L/H= 1.5 in terms of heat transfer enhancement and entropy generation minimization.

关键词： Pulsating flow entropy generation mixed convection heat transfer open cavity

Man Overboard Detection System Using IoT for Navigation Model

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Computers, Materials & Continua 2022年第6期71卷 4955-4969页

作者： Hüseyin Gürüler Murat Altun Faheem Khan Taegkeun Whangbo Department of Information Systems Engineering Mugla Sitki Kocman UniversityMuglaTurkey Artificial Intelligence Lab Department of Computer EngineeringGachon UniversityKorea

Security measures and contingency plans have been established in order to ensure human safety especially in the floating elements like ferry,roro,catamaran,frigate,yacht that are the vehicles services for the purpose of logistic and passenger *** this paper,all processes in the event of Man overboard(MOB)are initiated for smart *** MOB the falling person is totally dependent on the person who first saw the falling *** main objective of this paper is to develop a solution to this significant *** a staff member or a passenger does not see the fall into the sea,undesirable situations such as disappearance,injury and death can occur during the period until the absence of the fallen person is *** this paper,a comprehensive and improved solution is provided in terms of personnel and passenger security especially in all the floating elements,in which human resources are intensively involved like passengers,freight,logistics,fishing,business,yacht,leisure and naval *** this case,if the ship’s personnel or passengers fall into the sea in any way,it detected the fallen person into the sea by the sensors in the portable emergency device,which each person will *** warning system is activated via the in-ship automation system to which the information is transmitted by wireless ***,the case of MOB will be determined *** of things(IoT)has a key role in identifying the location and information of the person falling into the sea through sensors,radio frequency,GPS and connected ***,the alarm system on board will be activated and MOB flag(Oscar)will automatically be *** paper enables the Search and rescue(SAr)operations to be initiated and accelerated without losing time through decision-making process.

关键词： SAr internet of things man overboard arduino wireless communication smart transportation

Founder effects and the evolution of asymmetrical sexual isolation in a rapidly-speciating clade

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Current Zoology 2013年第2期59卷 230-238页

作者： Kevin r OH Gina L. CONTE Kerry L. SHAW Department of Neurobiology and Behavior Comell University Ithaca NY 14853 USA Department of Biology University of Maryland College Park MD 20742 USA

Sexual isolation resulting from differences in mate choice behaviors is a hallmark of rapidly-speciating lineages. When present, asymmetrical sexual isolation may provide insights into the mechanisms responsible for the evolutionary change in mate signaling traits. In particular, Kaneshiro＇s hypothesis suggests that divergence in sexual characters between populations may arise in allopatry when ＇derived＇ founding populations are subject to severe population bottlenecks, accompanied by a relaxation of sexual selection relative to ＇ancestral＇ source populations. In the present study, we tested predictions of asymmetrical sexual isolation between two allopatric species of Hawaiian Laupala crickets, representing ＇ancestral＇（L. makaio） and ＇derived＇（L. nigra） taxa. While crickets in this genus are notable for rapid divergence of male courtship songs, these species share similar song types, thus suggesting that patterns of sexual isolation are likely due to other mating cues. Analysis of behavioral responses in conspeci- fic and heterospecific ＇no-choice＇ mating trials revealed pronounced asymmetrical isolation in the direction predicted by Kane- shiro＇s hypothesis, wherein we observed a significant reduction in mating success for crosses involving ＇derived＇ males paired with ＇ancestral＇ females, compared to the reciprocal heterospecific and both conspecific pairings. Further dissection of courtship behaviors suggested this difference did not reflect male mate choice, but rather, marked reduced spermatophore acceptance rates by ＇ancestral＇ females paired with ＇derived＇ males. The results are discussed with respect to founder effect models of speciatiou and the potential role of chemosensory signals in mate choice in these species [Current Zoology 59 （2）： 230-238, 2013].

关键词： Prezygotic isolation Kaneshiro's hypothesis Founder flush models Laupala

Natural product based novel small molecules with promising neurotrophic,neurogenic and anti-neuroinflammatory actions can be developed as stroke therapeutics

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Neural regeneration research 2016年第6期11卷 916-917页

作者： Priya Jhelum r.gajendra reddy Arvind Kumar Sumana Chakravarty Chemical Biology CSIR-Indian Institute of Chemical TechnologyHyderabadIndia CSIr-Centre for Cellular and Molecular Biology HyderabadIndia

Stroke is the world’s second leading cause of death and a major cause of adult *** the different kinds of stroke,ischemic stroke is the most widely prevalent type,causing high morbidity and mortality worldwide（Mosko... 详细信息

关键词： neurotrophic neurogenic disability deprivation neurological neurotrophin nutrients hippocampal mortality regeneration

Assessment of reproductive Potential of Different Populations of Angelica glauca Edgew.,a Critically Endangered Himalayan Medicinal Herb

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Journal of Mountain Science 2008年第1期5卷 84-90页

作者： Anil Kumar Bisht Arvind Bhatt r.S.rawal Uppeandra Dhar G.B.Pant Institute of Himalayan Environment and Development Kosi-Katarmal Almora-263 643 (Uttarakhand)India

Angelica glauca is one of the important medicinal plants and it is widely used by indigenous communities for different purposes. The present study analyzes variability in reproductive characters of A. glauca. The reproductive parts were found having significant positive correlation with altitude (e.g.,number of umbellets /umber r= 0.857,pr r=0.735,p<0.05).

关键词： Angelica glauca critically endangered Himalaya medicinal plant population reproductive potential

Impacts of increased α-synuclein on clathrin-mediated endocytosis at synapses:implications for neurodegenerative diseases

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Neural regeneration research 2018年第4期13卷 647-648页

作者： Audrey T.Medeiros Luigi Bubacco Jennifer r.Morgan The Eugene Bell Center for regenerative Biology and Tissue Engineering Marine Biological Laboratory Department of Biology University of Padova

α-Synuclein causes synaptic pathologies in several neurodegenerative diseases：Parkinson’s disease（PD）is a neurodegenerative disease that impacts the lives of millions of people worldwide.A pathological hallmark of PD,as well as dementia with Lewy bodies（DLB）and several Alzheimer’s disease variants,is the appearanceof intracellular inclusions called Lewy bodies, which contain high levels of aggregated α-synuclein,

关键词： synuclein on clathrin-mediated endocytosis at synapses:implications for neurodegenerative diseases Impacts of increased

Outcome of gall bladder polypoidal lesions detected by transabdominal ultrasound scanning: A nine year experience

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World Journal of gastroenterology 2005年第14期11卷 2171-2173页

作者： D Chattopadhyay r Lochan S Balupuri Br Gopinath KS Wynne Hepatopancreatobiliary Surgery Unit Freeman Hospital Newcastle upon TyneNE30PLUK Department of Surgery South Tyneside District Hospital South ShieldsNE34 0PLUK

AIM: To determine the outcome of polypoidal lesions within the gall bladder (PLG) diagnosed by trans-abdominal ***: A nine-year (1993-2002) retrospective casenote review of all patients who underwent ultrasound scanning after referral to a single Upper GI Surgeon at a District General Hospital was conducted. Patients who were diagnosed with a PLG were included in our study. A database was constructed and patient details, investigations including ultrasound scan (USS) findings, treatment and histology and final diagnosis were recorded. rESULTS: Twenty-three (out of 651) patients were diagnosed pre-operatively by USS to have a polyp-likegall bladder lesion (PLG). Post cholecystectomy histological examination revealed 12 gallstones, 7 cholesterol polyps, 3 adenocarcinomas within polyps and 1 normal gall bladder. The specificity of USS in the diagnosis of PLG was 92.3%. All the true polyps were malignant. Overall USS had 66.66% sensitivity and 100% specificity in the pre-operative suspicion of malignancy. Using size greater than 10 mm as measured on USS as a cut-off, we find 100% sensitivity and 86.95% specificity with a positive predictive value of 50% in the diagnosis of malignancy in ***: A large number of PLG are in fact calculi within diseased gall bladder. In cases of gall bladder polyps more then 10 mm in size on USS further imaging (crosssectional and/or EUS) is indicated prior to surgery. This will help in the optimal management of patients and avoid histological surprises.

关键词： Polypoidal lesion in gall bladder Malignant polyps

A precise solution for prediction of fiber-reinforced concrete behavior under flexure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 495-502页

作者： r.AHMADI P.GHODDOUSI M.SHArIFI V.Mojarrad BAHrEH Building and House research Center Tehran 13145-1996Iran Department of Civil Engineering Iran University of Science and TechnologyTehran 16846-13114Iran Department of Civil Engineering Sharif University of TechnologyTehran 11365-11155Iran

This paper presents a precise solution to predict the behavior of steel fiber reinforced concrete(SFrC) under the four point bending test(FPBT).All the force components at the beam section(before and after cracking) are formulated by applying these assumptions:a realistic stress-strain model is used for concrete behavior in compression,a linear response is considered for the uncracked tension region in a concrete constitutive model,and an exponential relationship is proposed as a stress-crack opening in the crack region which requires two *** the moment capacity of the critical cracked section is calculated by using these forces and satisfying equilibrium law at the *** studies are done on the behavior of SFrC to assess the sensitivity of the ***,this solution is validated with some existing experimental *** result shows the proposed solution is able to estimate the behavior of SFrC under FPBT.

关键词： Steel fiber reinforced concrete(SFrC) Flexure Stress-crack opening Four point bending test(FPBT)

Soil Fertility Survey in Western Usambara Mountains, Northern Tanzania

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Pedosphere 2006年第2期16卷 237-244页

作者： P. A. NDAKIDEMI J. M. r. SEMOKA Selian Agricultural research Institute P.O. Box 6024 Arusha (Tanzania) Faculty of Applied ScienceCape Peninsula University of TechnologyCape Town CampusKeizersgrachtP. O. Box 652Cape Town 8000 (South Africa) Sokoine University of Agriculture Soil Science Department P. O. Box 3008Morogoro (Tanzania)

Soil samples from thirty sites representing four agro-ecological zones in the Western Usambara Mountains (WUM) of the Lushoto District in northern Tanzania were collected and analyzed for different nutrients. The results suggested that the major soil fertility constraint was P deficiency. On the basis of critical levels established in other areas, 90% of the soils were ranked as P deficient. This was followed by N, which was ranked as inadequate in 73% of the sites. Magnesium, K, and ca also appeared limiting with 67%, 53% and 50% of the soils falling below the established critical values, respectively. A few soils (10%) were also found to contain exchangeable Al. The metallic micronutrients (Cu, Fe, and Zn) were adequate in all soils. Two sites had excessive Mn that could lead to toxicity in crops, and one was Mn deficient.

关键词： agro-ecological zone P deficiency soil fertility Western Usambara Mountains