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GENETIc cONSEQUENcES OF INTRODUcED Gouramy Helostoma Temminckii (Pisces: Helostomatidae) IN BRUNEI'S WETLAND

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湿地科学 2003年第1期1卷 51-56页

作者： H.S.Zohrah P.H.c.Fauzani c. S. Jen O. Norsuzieyanti

Kissing gouramy (Helostoma temminckii) was introduced into Tasek Merimbun in the 1980's. We studied their genetic profile using allozyme electrophoresis and found that all loci were monomorphic. The loss of heterozygotes may suggest that the gouramy are inbreds. They must have reproduced by repeated sib-mating over the years. The severe drought in Tasek Merimbun may have aggravated the genetic erosion further. The genetic variability of kissing gouramy in terms of % polymorphic loci, mean number of alleles per loci and observed heterozygosity level were lower than cyprinids in the same lake and kissing gouramy from the wild. We also note that kissing gouramy is a fast grower and may threaten the livelihood of indigenous fishes in the lake.

关键词： Kissing gouramy introduced allozyme electrophoresis

Evaluation of hydrogeochemical characteristics and the impact of weathering in seepage water collected within the sedimentary formation

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Acta Geochimica 2017年第1期36卷 44-51页

作者： M.V.Prasanna R.Nagarajan S.chidambaram A.Anand Kumar c.Thivya Department of Applied Geology Faculty of Engineering and ScienceCurtin University Sarawak Department of Earth Sciences Annamalai University Department of Geology University of Madras

A study was conducted by collecting eight seepage water samples that drain through the sedimentary rocks, mainly sandstone and shale, to evaluate the hydro- geochemical characteristics. The collected samples were analyzed for physico-chemical parameters using standard procedures. Three water types were identified in the Piper plot and the hydrogeochemical evolution starts from a ca- c1 facies （type 1） via mixed ca-Mg-c1 and ca-Na-HcO3 facies （type 2） to Na-c1 facies （type 3）. Increasing trend of electrical conductivity （Ec） values were observed from type 1 water to type 3 water. Lower ionic concentrations with an average Ec value of 35.7 kts/cm in ca-c1 facies indicate the recharge water by monsoonal rainfall, and ion exchange/weathering process is reflected in the mixing zone. Higher ionic concentration with an average Ec value of 399 kts/cm is noted in Na-c1 facies, which indicates the ion exchange during water-rock interaction. Higher log pcO2 values are also found in this facies, revealing the longer residence time of seepage water in the rock matrix, which release more ions into the water. The relative mobility of elements during weathering suggest that the order of mobility in both sandstone and shale is Na 〉 ca 〉 Mg 〉 K. It was observed that thehydrogeochemistry of seepage water is mainly controlled by the bedrock geology.

关键词： Hydrogeochemistry Seepage water Water rock interaction Weathering Mobility of elements

Reliable Data collection Model and Transmission Framework in Large-Scale Wireless Medical Sensor Networks

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computer Modeling in Engineering & Sciences 2024年第7期140卷 1077-1102页

作者： Haosong Gou Gaoyi Zhang RenêRipardo calixto Senthil Kumar Jagatheesaperumal Victor Hugo c.de Albuquerque china Mobile Group Sichuan co. Ltd.Chengdu640041China Department of Teleinformatics Engineering Federal University of CearáFortaleza60455-970Brazil Department of Electronics&communication Engineering Mepco Schlenk Engineering CollegeSivakasi626005India

Large-scale wireless sensor networks(WSNs)play a critical role in monitoring dangerous scenarios and responding to medical ***,the inherent instability and error-prone nature of wireless links present significant challenges,necessitating efficient data collection and reliable transmission *** paper addresses the limitations of existing data transmission and recovery protocols by proposing a systematic end-to-end design tailored for medical event-driven cluster-based large-scale *** primary goal is to enhance the reliability of data collection and transmission services,ensuring a comprehensive and practical *** approach focuses on refining the hop-count-based routing scheme to achieve fairness in forwarding ***,it emphasizes reliable data collection within clusters and establishes robust data transmission over multiple *** systematic improvements are designed to optimize the overall performance of the WSN in real-world *** results of the proposed protocol validate its exceptional performance compared to other prominent data transmission *** evaluation spans varying sensor densities,wireless channel conditions,and packet transmission rates,showcasing the protocol’s superiority in ensuring reliable and efficient data *** systematic end-to-end design successfully addresses the challenges posed by the instability of wireless links in *** prioritizing fairness,reliability,and efficiency,the proposed protocol demonstrates its efficacy in enhancing data collection and transmission services,thereby offering a valuable contribution to the field of medical event-drivenWSNs.

关键词： Wireless sensor networks reliable data transmission medical emergencies cluster data collection routing scheme

Generation of time-varying orbital angular momentum beams with space-time-coding digital metasurface

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Advanced Photonics 2023年第3期5卷 92-100页

作者： Jingxin Zhang Peixing Li Ray c.c.cheung Alex M.H.Wong Jensen Li The Hong Kong University of Science and Technology Department of PhysicsHong KongChina city University of Hong Kong Department of Electrical EngineeringHong KongChina city University of Hong Kong State Key Laboratory of Terahertz and Millimeter WavesHong KongChina

The recently proposed extreme-ultraviolet beams with time-varying orbital angular momentum(OAM)realized by high-harmonic generation provide extraordinary tools for quantum excitation control and particle ***,such an approach is not easily scalable to other frequency *** design a space-time-coding digital metasurface operating in the microwave regime to experimentally generate time-varying OAM *** to the flexible programmability of the metasurface,a higher-order twist in the envelope wavefront structure of time-varying OAM beams can be further designed as an additional degree of *** time-varying OAM field patterns are dynamically mapped by developing a two-probe measurement *** approach in combining the programmability of space-time-coding digital metasurfaces and the two-probe measurement technique provides a versatile platform for generating and observing time-varying OAM and other spatiotemporal excitations in *** proposed time-varying OAM beams have application potentials in particle manipulation,time-division multiplexing,and information encryption.

关键词： time-varying orbital angular momentum digital-coding metasurfaces wavefront structure

crystal structures and biochemical studies of human lysophosphatidic acid phosphatase type 6

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Protein & cell 2013年第7期4卷 548-561页

作者： Jun Li Yu Dong Xingru Lü Lu Wang Wei Peng Xuejun c.Zhang Zihe Rao National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China University of chinese Academy of Sciences Beijing 100049China Structure Biology Laboratory Tsinghua UniversityBeijing 100084China Tianjin Key Laboratory of Protein Science College of Life SciencesNankai UniversityTianjin 300071China

Lysophosphatidic acid(LPA)is an important bioac-tive phospholipid involved in cell signaling through G-protein-coupled receptors *** is also involved in balancing the lipid composition inside the cell,and modulates the function of lipid rafts as an intermediate in phospholipid *** of its involvement in these important processes,LPA degradation needs to be regulated as precisely as its ***-tidic acid phosphatase type 6(AcP6)is an LPA-specifi c acid phosphatase that hydrolyzes LPA to monoacylglyc-erol(MAG)and ***,we report three crystal structures of human AcP6 in complex with malonate,L-(+)-tartrate and tris,*** analyses revealed that AcP6 possesses a highly conserved Rossmann-fold-like body domain as well as a less conserved cap *** vast hydrophobic substrate-binding pocket,which is located between those two domains,is suitable for ac-commodating LPA,and its shape is different from that of other histidine acid phosphatases,a fact that is consistent with the observed difference in substrate *** analysis of the binding of three molecules in the active site reveals the involvement of six conserved and crucial residues in binding of the LPA phosphate group and its *** structure also indicates a water-supplying channel for substrate *** structural data are consistent with the fact that the enzyme is active as a *** combination with additional mutagenesis and enzyme activity studies,our structural data provide important insights into substrate recognition and the mechanism for catalytic activity of AcP6.

关键词： lysophosphatidic acid histidine acid phos-phatase crystal structure

A Statistical Mechanical Analysis on the Bound State Solution of an Energy-Dependent Deformed Hulthén Potential Energy

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communications in Theoretical Physics 2019年第9期71卷 1127-1138页

作者： B.c.Lütfüoglu A.N.Ikot U.S.Okorie A.T.Ngiangia Department of Physics Faculty of ScienceAkdeniz University07058AntalyaTurkey Department of Physics Faculty of ScienceUniversity of Hradec KraloveRokitanskeho6250003Hradec KraloveCzechia Department of Physics Theoretical Physics GroupUniversity of Port HarcourtChobaPort HarcourtNigeria Department of Physics Akwa Ibom State UniversityIkot AkpadenP.M.B.1167UyoNigeria

In this article, we investigate the bound state solution of the Klein Gordon equation under mixed vector and scalar coupling of an energy-dependent deformed Hulthén potential in D dimensions. We obtain a transcendental equation after we impose the boundary conditions. We calculate energy spectra in four different limits and in arbitrary dimension via the Newton-Raphson method. Then, we use a statistical method, namely canonical partition function, and discuss the thermodynamic properties of the system in a comprehensive way. We find out that some of the thermodynamic properties overlap with each other, some of them do not.

关键词： Klein-Gordon equation energy-dependent deformed Hulthén potential energy bound state solution thermodynamic properties

Stem/progenitor cells in fetuses and newborns:overview of immunohistochemical markers

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cell Regeneration 2021年第1期10卷 239-250页

作者： D.Fanni c.Gerosa c.Loddo M.castagnola V.Fanos M.Zaffanello G.Faa Division of Pathology University Hospital San Giovanni Di Diovia Ospedale54CagliariItaly Department of Biology College of Science and TechnologyTemple UniversityPhidelphiaUSA Neonatal Intensive care Unit Department of Surgical SciencesUniversity of CagliariCagliariItaly Laboratory of Biochemistry and Metabolomics IRCCS Fondazione Santa LuciaRomeItaly Department of Surgical Sciences DentistryGynecology and PediatricsUniversity of VeronaPiazzale Stefani1I-37126 VeronaItaly

Microanatomy of the vast majority of human organs at birth is characterized by marked differences as compared toadult organs, regarding their architecture and the cell types detectable at histology. In preterm neonates, thesedifferences are even more evident, due to the lower level of organ maturation and to ongoing cell *** of the most remarkable finding in preterm tissues is the presence of huge amounts of stem/progenitor cells inmultiple organs, including kidney, brain, heart, adrenals, and lungs. In other organs, such as liver, the completelydifferent burden of cell types in preterm infants is mainly related to the different function of the liver duringgestation, mainly focused on hematopoiesis, a function that is taken by bone marrow after birth. Our preliminarystudies showed that the antigens expressed by stem/progenitors differ significantly from one organ to the ***, within each developing human tissue, reactivity for different stem cell markers also changes duringgestation, according with the multiple differentiation steps encountered by each progenitor during development. Abetter knowledge of stem/progenitor cells of preterms will allow neonatologists to boost preterm organmaturation, favoring the differentiation of the multiple cells types that characterize each organ in at term neonates.

关键词： Fetus Immunohistochemical analysis Newborn Progenitor cells Stem cells

PREDIcTION OF cARBON cONcENTRATION AND FERRITE VOLUME FRAcTION OF HOT-ROLLED STEEL STRIP DURING LAMINAR cOOLING

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Acta Metallurgica Sinica(English Letters) 2007年第4期20卷 251-257页

作者： Y.T. Zhang c.Z. Wang D.Z. Li Y.Y. Li School of Material Science and Engineering Shenyang Ligong University Shenyang 110168 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

A phase transformation model was presented for predicting the phase fraction transformed and the carbon concentration in austenite for austenite to ferrite transformation during laminar cooling on run-out table in hot rolling strip mill. In this model, the parameter k in Avrami equation was developed for carbon steels. The wide range of chemical composition, the primary austenite grain size, and the retained strain were taken into account. It can be used to predict the ferrite volume fraction and the carbon concentration in austenite of hot-rolled steel strip during laminar cooling on run-out table. The coiling temperature controlling model was also presented to calculate the temperature of steel strip. The transformation kinetics of austenite to ferrite and the evolution of carbon concentration in austenite at different temperatures during cooling were investigated in the hot rolled Q235B strip for thickness of 9.35, 6.4, and 3.2mm. The ferrite volume fraction along the length of the strip was also calculated. The calculated ferrite volume fraction was compared with the log data from hot strip mill and the calculated results were in agreement with the experimental ones. The present study is a part of the prediction of the mechanical properties of hot-rolled steel strip, and it has already been used on-line and off-line in the hot strip mill.

关键词： carbon concentration ferrite volume fraction laminar cooling hot rolling

An Experi mental Study on Wave-Induced Dynamic Stresses in Seabed

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china Ocean Engineering 2006年第1期20卷 27-44页

作者： S.c.chang L.K.chien J .G.Lin Y.F.chiu Department of Harbor and River Engineering National Taiwan Ocean University Taiwan China Harbor and Marine Technology center Taiwan China

A series of hydraulic model tests with horizontal movable seabed under regular wave actions have been carried out to investigate the dynamic interactions between water waves and seabed soil. Seabed dynamic stresses from experiments are, tound to differ from theoretical resuhs. The response of p0 in permeable seabed has a small decay and phase shift to the nonlinear wave actions, and the dynamic stresses, σs/p0, σh/p0 and u/p0, contain different phase shift characteristics. Such phenomena will strongly affect the dynamic stress path in seabed. If the phase shifts of σs. and σh are neglected, the stress path will become a straight line; otherwise, it will become an elliptical curve. In phase shift cases, the long axis of the p - q diagram will be shortened when the depth increases, and the short axis will become longer when the phase shift increases. For the p＇ - q＇ diagram, the larger the phase lag of u, the longer the short axis. Relative results offer useful information for the analysis of seabed stability.

关键词： wave-induced dynamic stresses movable seabed hydraulic model test stress path