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Advancement in utilization of magnetic resonance imaging and biomarkers in the understanding of schizophrenia

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World Journal of Clinical Cases 2025年第1期13卷 11-15页

作者： Aidan k Tirpack Danyaal G Buttar Mandeep kaur Department of Psychiatry Campbell University School of Osteopathic MedicineBuies CreekNC 27506United States Department of Psychiatry and Behavioral health Mercyhealth Hospital and Trauma CenterJanesvilleWI 53548United States

historically,psychiatric diagnoses have been made based on patient’s reported symptoms applying the criteria from diagnostic and statistical manual of mental *** utilization of neuroimaging or biomarkers to make the diagnosis and manage psychiatric disorders remains a distant *** have been several studies that examine brain imaging in psychiatric disorders,but more work is needed to elucidate the complexities of the human *** this editorial,we examine two articles by Xu et al and Stoyanov et al,that show developments in the direction of using neuroimaging to examine the brains of people with schizo-phrenia and *** et al used magnetic resonance imaging to examine the brain structure of patients with schizophrenia,in addition to examining neurotransmitter levels as *** et al used functional magnetic resonance imaging to look at modulation of different neural circuits by diagnostic-specific scales in patients with schizophrenia and *** two studies provide crucial evidence in advancing our understanding of the brain in prevalent psychiatric disorders.

关键词： Schizophrenia Magnetic resonance imaging Biomarkers Neurotransmitters Psychiatric disorders

Mechanical Property Prediction of Commercially Pure Titanium Welds with Artificial Neural Network

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Journal of Materials Science & Technology 2005年第3期21卷 403-407页

作者： YanhongWEI k.k.D.h.Bhadeshia T.Sourmail StatekeyLaboratoryofAdvancedWeldingProductionTechnology HarbinInstituteofTechnologyHarbin150001China DepartmentofMaterialsScienceandMetallurgy UniversityofCambridgeCambridgeCB23QZUK

Factors that affect weld mechanical properties of commercially pure titanium have been investigated using artificial neural networks. Input data were obtained from mechanical testing of single-pass, autogenous welds, and neural network models were used to predict the ultimate tensile strength, yield strength, elongation, reduction of area, Vickers hardness and Rockwell B hardness. The results show that both oxygen and nitrogen have the most significant effects on the strength while hydrogen has the least effect over the range investigated. Predictions of the mechanical properties are shown and agree well with those obtained using the 'oxygen equivalent' (OE) equations.

关键词： Commercially pure titanium Artificial neural networks Mechanical properties Weld

Microstructure and properties of hot extruded AZ31-0.25%Sb Mg-alloy

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中国有色金属学会会刊：英文版 2008年第A01期18卷 17-21页

作者：田素贵王岭 k.Y.ShON k.h.kIM School of Materials Sciences and Engineering Shenyang University of Technology Materials Engineering Department Korea Institute of Machinery and Materials

The effects of hot extrusion treatment on the microstructure and mechanical properties of AZ31-0.25%Sb Mg alloy were investigated by means of mechanical properties measurement and microstructure *** results show that the microstructure of AZ31-0.25%Sb Mg alloys consists ofα-Ms matrix,Mg_(17)Al_(12) and Mg_3Sb_2 *** ultimate tensile strength (UTS) and yield tensile strength(YTS) of the alloy are obviously enhanced by hot extrusion treatment,and the enhanced extent of UTS and YTS increases with the decrease of hot extrusion temperature,moreover,the YTS value of the alloy at RT,after extruded at 220℃,increases up to 131.4%,which attributes to the finer grains resulted from the dynamic recrystallization occurred during hot *** hot extrusion goes on,the slipping and concentration of dislocations continue to occur within the finer grains,which promotes the formation of the subgrains in the *** deformation features of the extruded alloy during tensile deformation at RT are the twinning deformation and dislocation slipping in the twinning ***,the deformation mechanisms of the alloy are a dislocation activation on the basal plane and a+c dislocation activation on the pyramidal planes.

关键词：镁合金高温挤压处理微观结构

Temperature distribution study during the friction stir welding process of Al2024-T3 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 779-787页

作者： Y.h.Yau A.hussain R.k.Lalwani h.k.Chan N.hakimi Department of Mechanical Engineering University of Malaya50603 KLMalaysia

heat flux characteristics are critical to good quality welding obtained in the important engineering alloy A12024- T3 by the friction stir welding （FSW） process. In the present study, thermocouples in three different configurations were amxed on the welding samples to measure the temperatures： in the first configuration, four thermocouples were placed at equivalent positions along one side of the welding direction; the second configuration involved two equivalent thermocouple locations on either side of the welding path; while the third configuration had all the thermocouples on one side of the layout but with unequal gaps from the welding line. A three-dimensional, non-linear ANSYS computational model, based on an approach applied to A12024-T3 for the first time, was used to simulate the welding temperature profiles obtained experimentally. The experimental thermal profiles on the whole were found to be in agreement with those calculated by the ANSYS model. The broad agreement between the two kinds of profiles validates the basis for derivation of the simulation model and provides an approach for the FSW simulation in A12024-T3 and is potentially more useful than models derived previously.

关键词： aluminum alloys friction stir welding welds temperature distribution

Strong coupling,charm- and bottom-quark masses from electron-positron annihilation

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Chinese Physics C 2010年第6期34卷 675-679页

作者： J.h.k.hn Institut für Theoretische Teilchenphysik Karlsruhe Institute of Technology

The cross section for electron-positron annihilation into hadrons allows for a precise determination of the strong coupling constant and the charm- and bottom-quark masses. Recent theoretical and experimental results ... 详细信息

关键词： strong coupling quark masses

SUPPORTING AND SEPARATING SUBSETS FOR INVEX BODIES

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Acta Mathematica Scientia 2008年第4期28卷 818-822页

作者： h.k.El-Sayied Mathematics Department Faculty of ScienceTanta University

Invex bodies represent an important class of bodies which are considered as a generalization of convex *** this article,the author studies the supporting for this class of bodies as well as the separating subsets of t... 详细信息

关键词： Invex bodies focal points-supporting separating

Effects of temperature-dependent viscosity variation on entropy generation, heat and fluid flow through a porous-saturated duct of rectangular cross-section

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Applied Mathematics and Mechanics(English Edition) 2007年第1期28卷 69-78页

作者： k.hooman h.Gurgenci School of Engineering the University of Queensland Brisbane Australia

Effect of temperature-dependent viscosity on fully developed forced convection in a duct of rectangular cross-section occupied by a fluid-saturated porous medium is investigated analytically. The Darcy flow model is applied and the viscosity-temperature relation is assumed to be an inverse-linear one. The case of uniform heat flux on the walls, i.e. the h boundary condition in the terminology of kays and Crawford [12], is treated. For the case of a fluid whose viscosity decreases with temperature, it is found that the effect of the variation is to increase the Nusselt number for heated walls. having found the velocity and the temperature distribution, the second law of thermodynamics is invoked to find the local and average entropy generation rate. Expressions for the entropy generation rate, the Bejan number, the heat transfer irreversibility, and the fluid flow irreversibility are presented in terms of the Brinkman number, the Péclet number, the viscosity variation number, the dimensionless wall heat flux, and the aspect ratio （width to height ratio）. These expressions let a parametric study of the problem based on which it is observed that the entropy generated due to flow in a duct of square cross-section is more than those of rectangular counterparts while increasing the aspect ratio decreases the entropy generation rate similar to what previously reported for the clear flow case by Ratts and Rant [14].

关键词： entropy generation rate forced convection porous medium rectangular duct temperature-dependent viscosity

ANALYSIS OF A COMPRESSIBLE GAS-LIQUID MODEL MOTIVATED BY OIL WELL CONTROL OPERATIONS

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Acta Mathematica Scientia 2012年第1期32卷 295-314页

作者： Steinar Evje k.h.karlsen Faculty of Science and Technology University of Stavanger Centre of Mathematics for Applications University of Oslo

We are interested in a viscous two-phase gas-liquid mixture model relevant for modeling of well control operations within the petroleum industry. We focus on a simplified mixture model and provide an existence result within an appropriate class of weak solutions. We demonstrate that upper and lower limits can be obtained for the gas and liquid masses which ensure that transition to single-phase regions do not occur. This is used together with appropriate a prior estimates to obtain convergence to a weak solution for a sequence of approximate solutions corresponding to mollified initial data. Moreover, by imposing an additional regularity condition on the initial masses, a uniqueness result is obtained. The framework.herein seems useful for further investigations of more realistic versions of the gas-liquid model that take into account different flow regimes.

关键词： gas-liquid two-phase model weak solution existence uniqueness

Petrology and Geochemistry of Post-Collisional Early Miocene Volcanism in the karacadag Area(Central Anatolia,Turkey)

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1100-1117页

作者： krsad ASAN hseyin kURT Department of Geological Engineering Selcuk University

Early Miocene（ca.21-18 Ma） volcanism in the karacadag area comprises three groups of volcanic rocks:（1） calcalkaline suite（andesitic to rhyolitic lavas and their pyroclastics）,（2） mildly-alkaline suite（alkali basalt,hawaiite,mugearite,benmoreite and trachydacite）,and（3） a single trachyandesitic flow *** observations,40Ar/39Ar ages and geochemical data show that there was a progressive temporal transition from group 1 to 3 in a post-collisional tectonic *** calcalkaline suite rocks with medium-k in composition resemble those of subduction-related lavas, whereas the mildly-alkaline suite rocks having a sodic tendency（Na2O/k2O=l.5-3.2） resemble those of within-plate *** element and Sr-Nd isotopic characteristics of the suites suggest that the lithospheric mantle beneath the karacadag area was heterogeneously enriched by two processes before collision:（1） enrichment by subduction-related processes,which is important in the genesis of the calcalkaline volcanism,（2） enrichment by small degree melts from the astenosphere,which dominates the mildly alkaline *** of the enriched lithosphere by either delamination following collision and uplift or removal of the subducted slab following subduction and collision（i.e.,slab breakoff） is the likely mechanism for the initiation of the post-collision volcanism.

关键词： post-collision calcalkaline Sr-Nd isotopes karacadag Central Anatolia