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The Trace Element Distribution Patterns of Ediacaran-Early Cambrian Black Shales and the Origin of Selenium in the Guangning Area, Western Guangdong Province, South China

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 1978-1991页

作者： TIAN Xinglei LUO Kunli Andrew V.ZUZA Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences university of the Chinese Academy of Sciences nevada Bureau of Mines and Geology University of Nevada

The Ediacaran and early Cambrian black shales are widespread across the South China Craton （Yangtze and Cathaysia blocks）. However, the trace element distribution patterns of the Ediacaran and early Cambrian black shales in the Cathaysia Block are still unclear. In this study, thirty- four black shale samples in the Lechangxia Group （Ediacaran） and thirteen black shale samples in the lower Bacun Group （early Cambrian） from Guangning area, western Guangdong Province, South China, were analyzed for major and trace elements concentrations. Compared to the upper continental crust, the Ediacaran black shales exhibit strongly enriched Se, Ga, and As with enrichment factor values （EF） higher than 10, significantly enrichedBi and Rb （10〉EF〉5）, weakly enriched Mo, Ba, Cs, V, In, Be, TI, and Th （5〉EF〉2）, normal U, Cr, Cd, Sc, Pb, Cu, and Li （2〉EF〉0.5）, and depleted Ni, Zn, Sr, and Co. Early Cambrian black shales display strongly enriched Se, Ga, and As, significantly enriched Ba, Bi, and Rb, weakly enriched Mo, Cs, Cd, V, U, Be, In, and TI, normal Sc, Th, Cr, Li, Cu, Ni, and Pb and depleted Co, Zn, and Sr. Moreover, Se is the most enriched trace element in the Ediacaran and early Cambrian black shales： concentrations vary from 0.25 to 30.09 ppm and 0.54 to 5.01 ppm, and averaging 4.84 and 1.72 ppm, with average EF values of 96.87 and 34.32, for the Ediacaran and early Cambrian shales respectively. The average concentration of Se in the Ediacaran black shales is 2.8 times higher than that of early Cambrian black shales. Se contents in the Ediacaran and early Cambrian black shales exhibit significant variation （P = 0.03）. Provenance analysis showed that Se contents of both the Ediacaran and early Cambrian black shales were without detrital provenance and volcanoclastic sources, hut of hydrothermal origin. The deep sources of Se and the presence of pyrite may explain the higher Se contents in the Ediacaran black shales. Similar with the Se-rich characteristics of the contemporan

关键词： black shale selenium Ediacaran and early Cambrian Guangning area Cathaysia block

Elaborations of the influencing factors on the formation of secondary inorganic aerosols in a heavily polluted urban area of China

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Journal of Environmental Sciences 2024年第4期138卷 406-417页

作者： Shuang Wang Qiyuan Wang Ting Zhang Suixin Liu Steven Sai Hang Ho Jie Tian Hui Su Yong Zhang Luyao Wang Tingting Wu Junji Cao School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Key Laboratory of Aerosol Chemistry and Physics State Key Laboratory of Loess and Quaternary GeologyInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain Xi’an 710061China Division of Atmospheric Sciences Desert Research InstituteRenoNevada89512United States Hong Kong Premium Services and Research Laboratory KowloonHong Kong SARChina Xi’an Institute for Innovative Earth Environment Research Xi’an 710061China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

In this study,online water-soluble inorganic ions were detected to deduce the formation mechanism of secondary inorganic aerosol in Xianyang,China during *** dominant inorganic ions of sulfate(SO_(4)^(2-)),nitrate(NO_(3)^(-)),and ammonium(NH_(4)^(+))(the sum of those is abbreviated as SNA)accounted for 17%,21%,and 12% of PM_(2.5)mass,*** the air quality deteriorated from excellent to poor grades,the precursor gas sulfur dioxide(SO_(2))of SO_(4)^(2-)increased and then decreased with a fluctuation,while nitrogen dioxide(NO_(2))and ammonia(NH_(3)),precursors of NO_(3)^(-)and NH_(4)^(+),and SNA show increasing *** factors including boundary layer height(BLH),temperature,and wind speed also show decline trends,except relative humidity(RH).Meanwhile,the secondary conversion ratio shows a remarkable increasing trend,indicating that there was a strong secondary *** the perspective of chemical mechanisms,RH is positively correlated with sulfur oxidation ratios(SOR),nitrogen oxidation ratios(NOR),and ammonia conversion ratios,representing that the increase of humidity could promote the generation of ***,SOR and NOR were also positively related to the *** the one hand,the low wind speed and BLH led to the accumulation of *** the other hand,the increases of RH and ammonia promoted more formations of SNA and PM_(2.5).The results advance our identification of the contributors to the haze episodes and assist to establish more efficient emission controls in Xianyang,in addition to other cities with similar emission and geographical characteristics.

关键词： Haze episodes Secondary inorganic aerosol Secondary conversion ratio Meteorological factors

An Annular Gap Acceleration Model for γ-ray Emission of Pulsars

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Chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 496-502页

作者： Guo-Jun Qiao Ke-Jia Lee Bing Zhang Hong-Guang Wang Ren-Xin Xu Department of Astronomy Peking University Beijing 100871 Department of Physics University of Nevada Las Vegas Nevada 89154 USA Center for Astrophysics Guangzhou University Guangzhou 510400

If the binding energy of the pulsar＇s surface is not so high （the case of a neutron star）, both negative and positive charges will flow out freely from the surface of the star. An annular free flow model for 7-ray emission of pulsars is suggested. It is emphasized that：（1） Two kinds of acceleration regions （annular and core） need to be taken into account. The annular acceleration region is defined by the magnetic field lines that cross the null charge surface within the light cylinder. （2） If the potential drop in the annular region of a pulsar is high enough （normally the case for young pulsars）, charges in both the annular and the core regions could be accelerated and produce primary gamma-rays. Secondary pairs are generated in both regions and stream outwards to power the broadband radiations. （3） The potential drop grows more rapidly in the annular region than in the core region. The annular acceleration process is a key process for producing the observed wide emission beams. （4） The advantages of both the polar cap and outer gap models are retained in this model. The geometric properties of the 7-ray emission from the annular flow are analogous to that pre-sented in a previous work by Qiao et al., which match the observations well. （5） Since charges with different signs leave the pulsar through the annular and the core regions respectively, the current closure problem can be partially solved.

关键词： pulsars: general - pulsars: - radiation mechanisms: non-thermal - stars:neutron - elementary particles

Resilience, the 6th Vital Sign: Conceptualizing, Contextualizing, and Operationalizing All Six Vital Signs

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Health 2024年第7期16卷 657-673页

作者： Rose E. Constantino Betty J. Braxter Chi Ching Vivian Hui Larissa C. Allen Lillian J. Wolfe Katherine H. Endres Jezyl Cempron Cutamora Laurence L. Garcia Daisy R. Palompon Kathleen Thimsen Brayden N. Kameg Margarete L. Zalon Department of Health and Community Systems School of Nursing University of Pittsburgh Pittsburgh PA USA Undergraduate Affairs School of Nursing University of Pittsburgh Pittsburgh PA USA The Hong Kong Polytechnic university Hong Kong China School of Nursing Adjunct Faculty at the University of Pittsburgh Pittsburgh PA USA School of Nursing University of Pittsburgh Pittsburgh PA USA Department of Health Promotion and Development School of Nursing University of Pittsburgh Pittsburgh PA USA College of Nursing Cebu Normal University Cebu City Philippines School of Nursing University of Nevada Las Vegas USA Department of Health and Community Systems University of Pittsburgh PA USA Department of Nursing University of Scranton Scranton PA USA

There are five vital signs that healthcare providers assess: temperature, pulse, respiration, blood pressure, and pain. Normal levels for the five vital signs are published by the American Heart Association, and other specialty organizations, however, the sixth vital sign (resilience) which adopts the measure of immune resilience is suggested in this paper. Resilience is the ability of the immune system to respond to attacks and defend effectively against infections and inflammatory stressors, and psychological resilience is the capacity to resist, adapt, recover, thrive, and grow from a challenge or a stressor. Individuals with better optimal immune resilience had better health outcomes than those with minimal immune resilience. The purpose of this paper is to conceptualize, contextualize, and operationalize all six vital signs. We suggest measuring resilience subjectively and objectively. Subjectively, use a 5-item guided interview revised from the Connor-Davidson Resilience Scale (CDRC), a scale of 10 items. The revised CDRC scale is a 5-item scale. The scale is rated on a 5-point Likert scale from 0 (not true) to 4 (true all the time). The total score ranges from 0 to 20, with higher total scores indicating greater resilience. The scale demonstrated good construct validity and internal consistency (α = 0.85) during the development of the scale. The CD-RISC had a good Cronbach’s alpha level of 0.85. The Revised CD-RISC can be completed in 2 - 4 minutes. To measure resilience objectively, we suggest using Immune Resilience (IR) levels, the level of resilience to preserve and/or rapidly restore immune resilience functions that promote disease resistance and control inflammation and other inflammatory stress. IR levels are gauged with two peripheral blood metrics that quantify the balance between CD8 and CD4 T-cell levels and gene expression signatures tracking longevity-associated immunocompetence and mortality- or entropy-associated inflammation. IR deregulation i

关键词： Conceptualization Contextualization Operationalization Body Temperature Pulse Respiration Blood Pressure Pain Resilience

Introduction to the themed articles on ionic polymer-metal composites

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International Journal of Smart and Nano Materials 2012年第3期3卷 183-187页

作者： Kam K. Leang Kwang J. Kim Department of Mechanical Engineering University of Nevada

Over the past two decades,we have observed an explosive growth in the field of electroactive polymers(EAPs),polymers that respond to external stimuli by changing their shape or size or even when mechanically stressed produce a measurable charge[1-6].Specifically,the research on the ionic EAP,such as ionic polymer-metal composites(IPMCs),has attracted international *** IPMC material has the ability to function as an actuator or a sensor in both air and wet environments,and generally IPMCs require low voltages(<5 V)for *** an IPMC is subjected to a voltage,deformation occurs due to the migration of ions and polar solvents within the polymer material.

关键词： composites material. IPMC

Direct ink writing to fabricate porous acetabular cups from titanium alloy

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Bio-Design and Manufacturing 2023年第2期6卷 121-135页

作者： Naima Valentin Weijian Hua Ashish K.Kasar Lily Raymond Pradeep L.Menezes Yifei Jin Mechanical Engineering Department University of NevadaRenoRenoNV 89557USA

Acetabular cups,which are among themost important implants in total hip arthroplasty,are usually made from titanium alloys with high porosity and adequate mechanical *** current three-dimensional(3D)printing approaches to fabricate customized acetabular cups have some inherent disadvantages such as high cost and energy consumption,residual thermal stress,and relatively low ***,in this work,a direct ink writing method was developed to print a cup structure at room temperature,followed by multi-step heat treatment to form microscale porous structure within the acetabular *** method is facilitated by the development of a self-supporting titanium-6 aluminum-4 vanadium(Ti64)ink that is composed of Ti64 particles,bentonite yield-stress additive,ultraviolet curable polymer,and *** effects of Ti64 and bentonite concentrations on the rheological properties and printability of inks were systematically ***,the printing conditions,geometrical limitations,and maximum curing depth were ***,some complex 3D structures,including lattices with different gap distances,honeycomb with a well-defined shape,and an acetabular cup with uniformly distributed micropores,were successfully printed/fabricated to validate the effectiveness of the proposed method.

关键词： Acetabular cup Direct ink writing Titanium alloy Bentonite Heat treatment

Effects of grid size on predictions of bed expansion in bubbling fluidized beds of Geldart B particles： A generalized rule for a grid-independent solution of TFM simulations

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Particuology 2017年第5期15卷 61-69页

作者： M. Helal Uddin Charles J. Coronella Department of Chemical and Materials Engineering University of Nevada Reno NV 89557 USA

Numerical simulations of gas-solid fluidized beds based on the kinetic theory of granular flow exhibit a significant dependence on domain discretization. Bubble formation, bubble size and shape all vary greatly with the discretization, and the use of an inappropriate scale resolution leads to inaccurate predictions of fluidization hydrodynamics. In this study, grid-independent solutions of the two fluid model were examined by comparing the bed expansions obtained from numerical simulations with experimental results and empirical predictions, based on bubbling fluidized beds of Geldart B particles. Grid indepen- dence was achieved with a grid resolution equal to 18 times the particle diameter. The simulation results were compared with previously published data for verification purposes. The results of this work should provide a guideline for choosing the appropriate grid size and thereby minimize the time and expense associated with large simulations.

关键词： Mesh effectHydrodynamicsComputational fluid dynamicsEuler-Euler method MFIX

Evaluation of different Krylov subspace methods for simulation of the water faucet problem

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Nuclear Science and Techniques 2021年第5期32卷 1-16页

作者： Hong-Yang Wei Kevin Briggs Victor Quintanilla Yi-Tung Chen Department of Mechanical Engineering University of NevadaLas VegasNV 89154USA

In this study,a one-dimensional two-phase flow four-equation model was developed to simulate the water faucet *** performance of six different Krylov subspace methods,namely the generalized minimal residual(GMRES),transpose-free quasi-minimal residual,quasi-minimal residual,conjugate gradient squared,biconjugate gradient stabilized,and biconjugate gradient,was evaluated with and without the application of an incomplete LU(ILU)factorization preconditioner for solving the water faucet *** simulation results indicate that using the ILU preconditioner with the Krylov subspace methods produces better convergence performance than that without the ILU *** the GMRES demonstrated an acceptable convergence performance under the Krylov subspace methods without the *** velocity and pressure distribution in the water faucet problem could be determined using the Krylov subspace methods with an ILU preconditioner,while GMRES could determine it without the need for a ***,there are significant advantages of using an ILU preconditioner with the GMRES in terms of *** different Krylov subspace methods showed similar performance in terms of computational efficiency under the application of the ILU preconditioner.

关键词： Water faucet problem Krylov subspace methods ILU preconditioner

MicroRNAs as potential biomarkers in temporal lobe epilepsy and mesial temporal lobe epilepsy

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Neural Regeneration Research 2023年第4期18卷 716-726页

作者： Bridget Martinez Philip V.Peplow Department of Pharmacology University of Nevada-RenoRenoNEVUSA Department of Medicine University of Nevada-RenoRenoNEVUSA Department of Anatomy University of OtagoDunedinNew Zealand

Temporal lobe epilepsy is the most common form of focal epilepsy in adults,accounting for one third of all diagnosed epileptic patients,with seizures originating from or involving mesial temporal structures such as the hippocampus,and many of these patients being refractory to treatment with anti-epileptic *** lobe epilepsy is the most common childhood neurological disorder and,compared with adults,the symptoms are greatly affected by age and brain *** of temporal lobe epilepsy relies on clinical examination,patient history,electroencephalographic recordings,and brain *** or delay in diagnosis is common.A molecular biomarker that could distinguish epilepsy from healthy subjects and other neurological conditions would allow for an earlier and more accurate diagnosis and appropriate treatment to be *** possible biomarkers of pathological changes as well as potential therapeutic targets in the epileptic brain are micro *** of the recent studies had performed micro RNA profiling in body fluids such as blood plasma and blood serum and brain tissues such as temporal cortex tissue and hippocampal tissue.A large number of micro RNAs were dysregulated when compared to healthy controls and with some overlap between individual studies that could serve as potential *** example,in adults with temporal lobe epilepsy,possible biomarkers are miR-199a-3p in blood plasma and miR-142-5p in blood plasma and blood *** adults with mesial temporal lobe epilepsy,possible biomarkers are miR-153 in blood plasma and miR-145-3p in blood ***,in many of the studies involving patients who receive one or several anti-epileptic drugs,the influence of these on micro RNA expression in body fluids and brain tissues is largely *** studies are warranted with children with temporal lobe epilepsy and consideration should be given to utilizing mouse or rat and non-human primate models of temporal lobe epil

关键词： adults biomarkers blood plasma blood serum children hippocampal tissue mesial temporal lobe epilepsy microRNA temporal cortical tissue temporal lobe epilepsy