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Paleoecology of Benthic Foraminifera in Coral Reefs Recorded in the Jurassic Tuwaiq Mountain Formation of the Khashm Al-Qaddiyah Area, Central saudi Arabia

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Journal of Earth science 2015年第2期26卷 224-235页

作者： Mohamed Youssef Abdelbaset s.El-sorogy Department of Geology and Geophysics College of Science King Saud University Department of Geology Faculty of Science South Valley University Department of Geology Faculty of Science Zagazig University

Thirty three benthic foraminiferal species belong to 23 genera and 16 families have been recorded from the coral reefs of the Callovian Tuwaiq Formation, Khashm AI-Qaddiyah area, Central saudi Arabia. Three species： Astacolus qaddiyahens.s, Nodosaria riyadhens.s, siderolites jurassica are believed to be new. Nearly all identified foraminifera are of Atlantie-Miditeranean affinity. The foraminiferal assemblage recorded in the present work is mixed of open marine, moderately deep marine conditions associations and shallow to deep lagoon. The reefal part of upper Twiaq Formation may have been deposited in shallow water of lower to middle shelf depth （20-50 m） as indicated by abundant corals and benthic foraminifera. The coral fauna and bearing benthic foraminifera indicated moderate water energy.

关键词： coral reef benthic foraminifera Jurassic Tuwaiq Formation saudi Arabia.

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Densification behavior of mechanically milled Cu–8 at% Cr alloy and its mechanical and electrical properties

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Progress in Natural science:Materials International 2014年第6期24卷 608-622页

作者： s.Patra Gouthama K.Mondaln Department of Materials.science and Engineering Indian Institute of Technology

synthes.s and consolidation behavior of Cu–8 at%Cr alloy powders made by mechanical alloying with elemental Cu and Cr powders,and subsequently,compressive and electrical properties of the consolidated alloys were *** solubility of Cr in Cu during milling,and subsequent phase transformations during sintering and heat treatment of sintered components were analyzed using X-ray diffraction,scanning electron microscopy and transmission electron *** milled powders were compacted applying three different pressures(200 MPa,400 MPa and 600 MPa)and sintered in H2atmosphere at 900 1C for 30 min and at 1000 1C for 1 h and 2 *** maximum densification(92.8%)was achieved for the sample compacted at 600 MPa and sintered for 1000 1C for 2 *** and densification behavior further increased for the compacts.sintered at 900 1C for 30 min after rolling and annealing *** investigation of the sintered compacts revealed the bimodal distribution of Cu grains with nano-sized Cr and Cr2O3precipitation along the grain boundary as well as in grain *** of grain boundaries by the precipitates.stabilized the fine grain structure in bimodal distribution.

关键词： Electron microscopy X-ray diffraction Mechanical alloying Cu-based alloys Nanostructured materials

The“Tears of the Virgin”at Lakes Entrance,southeast Australia were made by the intertidal barnacle Chthamalus antennatus(Cirripedia:Thoracica)and cyanobacteria

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Integrative Zoology 2017年第3期12卷 228-236页

作者： John s.BUCKERIDGE William A.NEWMAN Earth&Oceanic s.stems Group RMIT UniversityMelbourneVictoriaAustralia scripps Institution of Oceanography La JollaCaliforniaUSA

Curious eroded depressions,most resembling an eye shedding an elongate tear,are found in gently sloping,intertidal,carbonate-rich arenite outcropping on the sea coast near Lakes Entrance,Victoria,southeast *** depressions,known locally as“Tears of the Virgin,”are evidently formed by multiple generations of a barnacle,Chthamalus antennatus Darwin,1854 in association with *** the round part of a depression offers the barnacle a modicum of protection from impacts during high tides,it is also partially inhabited by cyanobacteria,which extend into and tend to fill the elongate *** such,this appears to be the first case of mutualism between a higher invertebrate and cyanobacteria,with the cyanobacteria reducing the barnacle’s risk of desiccation while receiving metabolic wastes from it during low *** is also the first record of a balanomorph barnacle eroding calcareous arenite beneath its.shell,the net effect of which would be expected to reduce its adhesion to the ***,the siliceous residue,resulting from the barnacle’s dissolution of the more than 80%of the calcite-rich sedimentary rock,is.sequestered in delicate folds on the inside of the shell wall as it grows.A brief review of cirripedes capable of excavation includes the first photographic documentation of excavation of a mollusc shell by a verrucomorph.

关键词： burrowing barnacles Chthamalus antennatus Cirripedia cyanobacteria mutualism

Iterative computational approach to the solution of the Hamilton-Jacobi-Bellman-lsaacs equation in nonlinear optimal control

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Control Theory and Technology 2018年第1期16卷 38-48页

作者： M. D. s. ALIYU Department of Electrical Engineering King Faisal University AI-Ahsa 31982 Saudi Arabia

In this paper, iterative or successive approximation methods for the Hamilton-Jacobi-Bellman-lsaacs equations （HJBIEs） arising in both deterministic and stochastic optimal control for affine nonlinear s.stems are developed. Convergence of the methods are established under fairly mild assumptions, and examples are solved to demonstrate the effectiveness of the methods. However, the results presented in the paper are preliminary, and do not yet imply in anyway that the solutions computed will be stabilizing. More improvements and experimentation will be required before a satisfactory algorithm is developed.

关键词： Hamilton-Jacobi-Bellman-lsaac equation vector identity fixed-point theory successive approximation method,bounded continuous functions convergence Riccati equation

Prostate cancer risk-associated genetic markers and their potential clinical utility

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Asian Journal of Andrology 2013年第3期15卷 314-322页

作者： Jianfeng Xu Jielin sun s Lilly Zheng Fudan Institute of Urology Huashan Hospital Fudan University Shanghai 200040 China state Key Laboratory of Genetic Engineering Fudan University Shanghai 200433 China Center for Genetic Epidemiology School of Life Sciences Fudan University Shanghai 200433 China Center for Cancer Genomics Wake Forest School of Medicine Winston-Salem NC 27157 USA

Prostate cancer （PCa） is one of the most common cancers among men in Western developed countries and its incidence has increased considerably in many other parts of the world, including China. The etiology of PCa is largely unknown but is thought to be multifactorial, where inherited genetics plays an important role. In this article, we first briefly review results from studies of familial aggregation and genetic s.sceptibility to PCa. We then recap key findings of rare and high-penetrance PCa s.sceptibility genes from linkage studies in PCa families. We devote a significant portion of this article to summarizing discoveries of common and Iow-penetrance PCa risk-associated single-nucleotide polymorphis.s （sNPs） from genetic association studies in PCa cas.s and controls, especially those from genome-wide association studies （GWAss）. A strong focus of this article is to review the literature on the potential clinical utility of these implicated genetic markers. Most of these published studies described PCa risk estimation using a genetic score derived from multiple risk-associated sNPs and its utility in determining the need for prostate biopsy. Finally, we comment on the newly proposed concept of genetic score; the notion is to treat it as a marker for genetic predisposition, similar to family history, rather than a diagnostic marker to discriminate PCa patients from non-cancer patients. Available evidence to date sugges.s that genetic score is an objective and better measurement of inherited risk of PCa than family history. Another unique feature of this article is the inclusion of genetic association studies of PCa in Chinese and Japanese populations.

关键词： biopsy Chinese family history genetic score heritability prostate cancer (PCa) prostate-specific antigen (PsA) PsA screen singie-nucleotide polymorphis.s (sNPs)

Facile synthes.s as well as.structural, Raman, Dielectric and Antibacterial Characteristics of Cu Doped ZnO Nanoparticles

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Journal of Materials.science & Technology 2015年第3期31卷 300-304页

作者： Javed Iqbal Nauman safdar Tariq Jan Muhammad Ismail s.s.Hussain Arshad Mahmood shaheen shahzad Qaisar Mansoor Laboratory of Nanoscience and Technology Department of Physics International Islamic University Institute of Biomedical and Genetic Engineering (IBGE) Nano Devices Labs National Institute of Lasers and Optronics (NILOP) Department of Bioinformatics and Biotechnology International Islamic University

Here, undoped and Cu doped ZnO nanoparticles(NPs) have been prepared by chemical co-precipitation technique. X-ray diffraction(XRD) results reveal that Cu ions are successfully doped into ZnO matrix without altering its wurtzite phase. The single wurtzite phase of ZnO is retained even for 10 wt% Cu doped ZnO sample. It is observed from the electron microscopy results that higher level of Cu doping varies the morphology of ZnO NPs from spherical to flat NPs. Moreover, the particle size is found to increase with the increase in Cu doping level. Raman spectroscopy results further confirm that Cu dopant has not altered the wurtzite structure of ZnO. Impedance spectroscopy results reveal that the dielectric constant and dielectric loss have increasing trend with Cu doping. Cu doping has been found to slightly decrease the bactericidal potency of ZnO nanoparticles.

关键词： Cu doped ZnO Nanoparticles Co-precipitation method

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Variable fluid properties and thermal radiation effects on flow and heat transfer in micropolar fluid film past moving permeable infinite flat plate with slip velocity

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Applied Mathematics and Mechanics(English Edition) 2012年第5期33卷 663-678页

作者： M.A.A.MAHMOUD s.E.WAHEED Department of Mathematics Faculty of ScienceBenha UniversityBenha 13518Egypt

This work deals with the influence of thermal radiation on the problem of the mixed convection thin film flow and heat transfer of a micropolar fluid past a moving infinite vertical porous flat plate with a slip velocity. The fluid viscosity and the thermal conductivity are assumed to be the functions of temperature. The equations governing the flow are solved numerically by the Chebyshev spectral method for some representative value of various parameters. In comparison with the previously published work, the excellent agreement is.shown. The effects of various parameters on the velocity, the microrotation velocity, and the temperature profiles, as well as the skin-friction coefficient and the Nusselt number, are plotted and discussed.

关键词： micropolar fluid thin film slip velocity variable fluid properties thermalradiation Chebyshev spectral method

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A study of the Number of Roots of xk =g in a Finite Group via Its Frobenius.schur Indicators

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Algebra Colloquium 2017年第1期24卷 93-108页

作者： s.K. Prajapati R. sarma Department of Mathematics Indian Institute of Technology Delhi Hauz Khas New Delhi 110016 India

Let G be a finite group. For k ∈ N, X ∈ Irr（G）, define c（k）x ：= 1/G ∑g∈G x（gk）. This is called the k-th Frobenius.schur indicator of X. In this article we study the Probenius.schur indicators for Frobenius groups, p-groups, semidihedral groups and mod- ular p-groups. Further, we use this to study the function ζ kG（g） which counts the number of roots of xk = g in a finite group G.

关键词： Frobenius.schur indicators p-groups group characters

Nanosecond Pulse Generation Using the stimulated Brillouin scattering Effect in a Photonic Crystal Fiber

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Chinese Physics Letters 2013年第11期30卷 99-101页

作者： Z.Jusoh N.s.shahabuddin N.M.Ali H.Ahmad s.W.Harun Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia Photonic Research Centre University of Malaya50603 Kuala LumpurMalaysia Faculty of Electrical Engineering Universiti Teknologi MARA(UiTM)40450 Shah AlamMalaysia

A nanosecond pulsed laser is demonstrated using the stimulated Brillouin scattering(s.s)effect in a nonlinear photonic crystal fiber(PCF).The Brillouin fiber laser(BFL)us.s a 50-m-long PCF in a simple ring cavity to generate a self-starting pulse as the Brillouin power reaches 16.5 dBm based on the relaxation oscillation *** BFL generates a pulse train with repetition rates of 2.7 MHz and 5.4 MHz depending on the BP *** pulse width of the laser is obtained to be 190 ns at the BP power of 16.5 dBm and is maintained at around 72 ns as the pump power is.set within 17.7 dBm and 18.5 *** maximum pulse energy of 20 nJ is obtained at BP power of 17.4 *** s.s based pulse laser is fairly stable at room temperature.

关键词： fiber pump scattering