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应用数学与计算数学学报 2017年第2期31卷 143-152页

作者： bELOv A v los A b ROZHKOv M I 高等经济大学俄罗斯莫斯科101000

研究在有限域上构造MDS方阵的一些方法,这类矩阵作为扩散映射用于构建块加密算法和检验函数.给出了若干类4阶循环MDS矩阵以及具有最多单位元的4阶MDS矩阵.

关键词： MDS矩阵 MDS编码数据保护算法

Species Richness and Abundance of bivalves and Gastropods in Mangrove Forests of casiguran, Aurora, Philippines

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Open Journal of Ecology 2020年第12期10卷 778-787页

作者： Maria Cristina b. cañada Research and Development Services Office Aurora State College of Technology Baler Aurora Philippines

The diversity and abundance of bivalves and gastropods were studied from April to July 2015. Two sampling stations, Tinib and Esteves, in casiguran, Aurora were selected based on the presence of mangrove forest, bivalves, gastropods, muddy substrate, and gleaners for the establishment of a transect line. Each station was laid with 100 meters transect line overlaid continuously with 2 m × 2 m quadrat along each transect. A total of 50 sampling units covering 0.02 ha area per sampling station were surveyed. The transect line recorded six species of bivalves distributed among five families and 12 species of gastropods belonging to eight families. Three species of bivalves and five species of gastropods were common to both sampling stations. However, Tinib station had most diverse species of bivalves (0.55) while Esteves station had most diverse species of gastropods (0.43). both stations revealed Dendrostrea folium (43%) (bivalve) and Cerithidea cingulata (93%) (gastropods) as most frequently occurring species. Dendostrea folium also emerged as the densest (10,640 ind∙ha−1 and 6850 ind∙ha−1) and most abundant (58.52% and 77.84%) bivalve species. For gastropods, Terebralia sulcata (249,250 ind∙ha−1) was the densest and most abundant (96.97%) in Tinib while Terebralia palustris was the densest (747,050 ind∙ha−1) and most abundant (70.44%) in Esteves. Pooled results for bivalve species maintained Dendrostrea folium as the densest (8750 ind∙ha

Perspectives on atmospheric mercury and its fate in aquatic ecosystems

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Journal of Environmental Sciences 2000年第S1期12卷 85-91页

作者： D.b. Porcella (1034 Lindsey Court, Lafayette ca 94549 USA E mail: dporcell@***)

Mercury (Hg) is a neurotoxin to humans and wildlife that has a quantitatively important gas phase that makes its atmospheric cycle an important part of exposure pathways to these organisms. The important atmospheric forms are elemental Hg (Hg(0)), inorganic gas phase Hg (HgH gs ), and inorganic particulate Hg(HgIIp). Each form has different behavior depending on its chemical and physical properties. Generally, scientists have found with trace metal clean sampling and analytical techniques, that background Hg levels are 1—2 ng/m\+3 in air, 0.1—2 ng/L in surface waters, 5—25 ng/L in rainwater, and less than 0.1 μg/g in sediments remote from natural Hg minerals and wastewater sources. values in excess of these concentrations generally indicate local anthropogenic influences or contaminated samples. broad scale estimates of Hg inputs to the atmosphere suggest that annual anthropogenic fluxes to the atmosphere as Hg(0) are about 40 percent of the total global cycle, oceanic evasion is about 40 percent, and (by difference) the remaining input to the global cycle (20 percent) is evasion from terrestrial sources, largely via soils and vegetation. This paper summarizes recent data that will constrain estimates from these sources. For example, terrestrial sources could approach 40 percent and annual anthropogenic inputs be correspondingly less. Furthermore, a historic perspective is needed because Hg has cycled atmospherically over geologic time. In addition to the uncertainty in source quantification, methylation must be a focus of risk analysis, because this process is responsible for risks to human and ecosystem health for almost all modern day Hg exposures.

关键词： Perspectives on atmospheric mercury and its fate in aquatic ecosystems

Arsenic and chromium resistance mechanisms in the Micrococcus luteus group

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Pedosphere 2023年第4期33卷 600-611页

作者： Ivan ARROYO-HERREra brenda ROMÁN-PONCE rafael bUSTAMANTE-bRITO Joseph GUEvAra-LUNA Erika Yanet TAPIA-GARCÍA violeta LARIOS-SERraTO Nannan ZHANG Paulina ESTraDA-DE los SANTOS En Tao WANG María Soledad vÁSQUEZ-MURRIETA Escuela Nacional de Ciencias biológicas Instituto Politécnico NacionalCiudad de México 11340(Mexico) Universidad Politécnica del Estado de Morelos Jiutepec 62550(Mexico) Centro de Ciencias Genómicas Universidad Autónoma de MéxicoCuernavaca 62210(Mexico) caS Key Laboratory of Mountain Ecological Restoration and bioresource Utilisation&Ecological Restoration and biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041(China)

High arsenic(As)and chromium(Cr)concentrations are currently receiving attention because of their negative effects on the environment and human *** inhabiting contaminated environments have developed resistance mechanisms against the toxicity of these ***,members of the bacterial genus Micrococcus have been isolated from different toxic metal-contaminated environments;however,knowledge concerning its resistance mechanisms to As and Cr toxicity remains *** luteus strains(An24,Mh,NE2TL6,and NE2TTS4)were isolated from the endosphere and soil of two heavy metal-contaminated sites in Mexico to identify differences in the resistance mechanisms by the *** *** strains were resistant to As(As^(3+)and As^(5+)),chromate,dichromate,cobalt,copper,nickel,and *** analysis indicated that the heavy metal-resistant strains(An24,Mh,NE2TL6,and NE2TTS4)could be assigned to the *** group and had more heavy metal-resistant genes(transporters,chaperones,and enzymes)compared to reference strains of the *** group,*** NCTC 2665^(T)and Micrococcus endophyticus JCM 16951^(T).The resistant bacteria were able to biotransform As^(3+)and As^(5+)through a carbon source-dependent *** biotransformation of As5+was potentially carried out in the cytoplasm through a thioredoxin-dependent pathway,which may be coupled with biosorption.A qualitative analysis of organic acids(OAs)identified a change in the OA profile of the metal-resistant strains that was As-or *** genomic and phenotypic findings suggest that the four *** group strains evaluated in the current study have developed resistance mechanisms that may enable their survival in contaminated sites.

关键词： arsenophore biosorption genome analysis heavy metal-resistant strain immobilization organic acid pollutant

古新世-始新世极热事件期间的浊积岩沉积对气候变化和天文旋回的响应

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第四纪研究 2024年第5期44卷 1225-1234页

作者：金思敏 David b.KEMP 张仲石黄春菊刘晴中国地质大学(武汉)环境学院大气科学系湖北武汉430074 中国地质大学(武汉)地球科学学院生物地质与环境地质国家重点实验室关键带演化湖北省重点实验室湖北武汉430074

浊流是地表最重要的沉积物运移过程之一,主导了沉积物从大陆架到深海的输送。通过研究深时极热事件期间浊流的分布规律,可为类比推测未来全球变暖背景下浊流活动的变化趋势提供重要参考。前期研究发现,古新世-始新世极热事件(PETM)期间... 详细信息

浊流是地表最重要的沉积物运移过程之一,主导了沉积物从大陆架到深海的输送。通过研究深时极热事件期间浊流的分布规律,可为类比推测未来全球变暖背景下浊流活动的变化趋势提供重要参考。前期研究发现,古新世-始新世极热事件(PETM)期间,英国东部北海盆地的高频浊积砂岩沉积受到了气候变化的影响。本研究进一步对西班牙basque盆地Zumaia剖面古新统-始新统458层浊积岩(深度范围为-19.76~37.12 m)进行了时间序列分析,发现浊积岩沉积存在着显著的405 ka长偏心率周期信号。通过总结古新统-始新统浊积岩记录对天文旋回的响应,发现仅在英国北海盆地和西班牙basque盆地识别出了天文旋回信号,且这两个点位的地理位置与模拟结果显示的年平均降水对轨道参数变化的敏感区相吻合。此外,本研究还讨论了PETM期间不同沉积环境中浊积岩沉积记录对海平面变化和全球升温的响应。

关键词：古新世-始新世极热事件天文旋回浊积岩偏心率岁差

Grain to outcrop-scale frozen moments of dynamic magma mixing in the syenite magma chamber,Yelagiri Alkaline Complex,South India

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Geoscience Frontiers 2014年第6期5卷 801-820页

作者： M.L.Renjith S.N.Charan D.v.Subbarao E.v.S.S.K.babu v.b.rajashekhar Marine and Coastal Survey Division Geological Survey of IndiaCochin 682037India Geochemistry Division CSIR-National Geophysical Research InstituteHyderabad 500007India New Zealand Petroleum and Minerals Wellington 6037New Zealand

Magma mixing process is unusual in the petrogenesis of felsic rocks associated with alkaline complex worldwide. Here we present a rare example of magma mixing in syenite from the Yelagiri Alkaline Complex, South India. Yelagiri syenite is a reversely zoned massif with shoshonitic (Na2O t K2O?5e 10 wt.%, Na2O/K2O ? 0.5e2, TiO2racter. Systematic modal variation of plagioclase (An11e16 Ab82e88), K-feldspar (Or27e95 Ab5e61), diopside (En34e40Fs11e18Wo46e49), biotite, and ca-amphibole (edenite) build up three syenite facies within it and imply the role of in-situ fractional crystallization (FC). Evidences such as (1) disequilibrium micro-textures in feldspars, (2) microgranular mafic enclaves (MME) and (3) synplutonic dykes signify mixing of shoshonitic mafic magma (MgO ? 4e 5 wt.%, SiO2 ? 54e59 wt.%, K2O/Na2O ? 0.4e0.9) with syenite. Molecular-scale mixing of mafic magma resulted disequilibrium growth of feldspars in syenite. Physical entity of mafic magma preserved as MME due to high thermal-rheological contrast with syenite magma show various hybridization through chemical exchange, mechanical dilution enhanced by chaotic advection and phenocryst migration. In synplutonic dykes, disaggregation and mixing of mafic magma was confined within the conduit of injec-tion. Major-oxides mass balance test quantified that approximately 0.6 portions of mafic magma had interacted with most evolved syenite magma and generated most hybridized MME and dyke samples. It is unique that all the rock types (syenite, MME and synplutonic dykes) share similar shoshonitic and met-aluminous character;mineral chemistry, REE content, coherent geochemical variation in Harker diagram suggest that mixing of magma between similar composition. Outcrop-scale features of crystal accumu-lation and flow fabrics also significant along with MME and synplutonic dykes in syenite suggesting that Yelagiri syenite magma chamber had evolved through multiple physical processes like

关键词： Magma mixing Disequilibrium textures Petrology Synplutonic dykes Geodynamics

boundary Plasma Turbulence Simulations for Tokamaks

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Communications in Computational Physics 2008年第10期4卷 949-979页

作者： X.Q.Xu M.v.Umansky b.Dudson P.b.Snyder Lawrence Livermore National Laboratory L-630P.O.Box 8087000 East Ave.LivermoreCA 94550USA Institute of Fusion Theory and Simulation ZhejiangUniversityHangzhou 310027China Department of Physics University of YorkHeslingtonYorkYO105DDUK General Atomics 13-303P.O.Box 85608San DiegoCA 92186-5608USA.

The boundary plasma turbulence code bOUT models tokamak boundaryplasma turbulence in a realistic divertor geometry usingmodified braginskii equations for plasma vorticity,density(ni),electron and ion temperature(Te,Ti)and *** bOUT code solves for the plasma fluid equations in a three dimensional(3D)toroidal segment(or a toroidal wedge),including the region somewhat inside the separatrix and extending into the scrape-off layer;the private flux region is also *** this paper,a description is given of the sophisticated physical models,innovative numerical algorithms,and modern software design used to simulate edgeplasmas in magnetic fusion energy *** bOUT code’s unique capabilities and functionality are exemplified via simulations of the impact of plasma density on tokamak edge turbulence and blob dynamics.

关键词： Plasma turbulence simulation plasma two-fluids equation field-aligned coordinates plasma blobs

The outcomes and safety of patients undergoing endoscopic retrograde cholangiopancreatography combining a single-use cholangioscope and a single-use duodenoscope:A multicenter retrospective international study

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 71-76页

作者： Alessandro Fugazza Matteo Colombo Michel Kahaleh v.raman Muthusamy bick benjamin Wim Laleman carmelo barbera carlo Fabbri Jose Nieto Abed Al-Lehibi Mohan ramchandani Amy Tyberg Haroon Shahid Avik Sarkar Dean Ehrlich Stuart Shermand Cecilia binda Marco Spadaccini Andrea Iannone Kareem Khalaf Nageshwar Reddy Andrea Anderloni Alessandro Repici Division of Gastroenterology and Digestive Endoscopy Humanitas Research Hospital-IRCCSVia Manzoni 5620089RozzanoMilanoItaly Gastroenterology Rutgers Robert Wood JohnsonNew BrunswickNew JerseyUSA vatche and Tamar Manoukian Division of Digestive Diseases University of CaliforniaLos Angeles School of Medicine at UCLALos AngelesCaliforniaUSA Division of Digestive and Liver Disorders Indiana University School of MedicineIndianapolisINUSA Department of Gastroenterology and Hepatology University Hospitals LeuvenKU Leuven3000 LeuvenBelgium U.O.C.di Gastroenterologia ed Endoscopia Digestiva Ospedale Giuseppe MazziniASL TeramoItaly Gastroenterology and Digestive Endoscopy Unit Forlì-Cesena HospitalsAUSL RomagnaForlì-CesenaItaly borland Groover Clinic JacksonvilleFloridaUSA Department of Gastroenterology and Hepatology King Fahad Medical CityRiyadhSaudi Arabia Asian Institute of Gastroenterology HyderabadIndia Section of Gastroenterology Department of Emergency and Organ TransplantationUniversity of BariBari 70124Italy Department of biomedical Sciences Humanitas UniversityVia Rita Levi Montalcini 420090Pieve EmanueleMilanItaly

background: Duodenoscope-related multidrug-resistant organism(MDRO) infections raise concerns. Disposable duodenoscopes have been recently introduced in the market and approved by regulatory agencies with the aim to reduce the risk of endoscopic retrograde cholangiopancreatography(ERCP) associated infections. The aim of this study was to evaluate the outcome of procedures performed with single-use duodenoscopes in patients with clinical indications to single-operator cholangiopancreatoscopy. Methods: This is a multicenter international, retrospective study combining all patients who underwent complex biliopancreatic interventions using the combination of a single-use duodenoscope and a single-use cholangioscope. The primary outcome was technical success defined as ERCP completion for the intended clinical indication. Secondary outcomes were procedural duration, rate of cross-over to reusable duodenoscope, operator-reported satisfaction score(1 to 10) on performance rating of the single-use duodenoscope, and adverse event(AE) rate. Results: A total of 66 patients(26, 39.4% female) were included in the study. ERCP was categorized according to ASGE ERCP grading system as 47(71.2%) grade 3 and 19(28.8%) grade 4. The technical success rate was 98.5%(65/66). Procedural duration was 64(interquartile range 15-189) min, cross-over rate to reusable duodenoscope was 1/66(1.5%). The satisfaction score of the single-use duodenoscope classified by the operators was 8.6 ± 1.3 points. Four patients(6.1%) experienced AEs not directly related to the single-use duodenoscope, namely 2 post-ERCP pancreatitis(PEP), 1 cholangitis and 1 ***: Single-use duodenoscope is effective, reliable and safe even in technically challenging procedures with a non-inferiority to reusable duodenoscope, making these devices a viable alternative to standard reusable equipment.

关键词： Single-operator cholangioscopy Single-use duodenoscope Endoscopic retrograde cholangiopancreatography Indeterminate biliary stricture Difficult biliary stones

A Novel Rituximab Polymer leads to CD20 Hyper-crosslinking-induced apoptosis in Non-Hodgkin’s Lymphomas

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A Novel Rituximab Polymer leads to CD20 Hyper-crosslinking-i...

POLES OF ZETA FUNCTIONS OF COMPLETE INTERSECTIONS

中国化学会第四届有机化学学术会议

作者： Peisheng Hu Department of Pathology, University of Southern california. 2011 Zonal Avenue, los Angeles, ca ,USA

＜正＞Although monoclonal （mAb） antibody Rituximab treatment has produced significant tumor regression in patients with relapsed b-cell non-Hodgkin s lymphoma, only 50% of overall patients respond. Clinically, it has been shown that the major memchanism of Rituximab is antibody-dependent cytotoxicity requiring presentation by Fc-bearing cells. To improve the clinical efficacy of Rituximab for treatment of CD20 positive lymphomas, we have generated a stable

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Chinese Annals of Mathematics,Series b 2000年第2期21卷 187-200页

作者： WAN DAQING(Department of Mathematics, University of california, Irvine, ca 92697-3875, USA.) Department of Mathematics University of California Irvine CA 92697-3875 USA

A vanishing theorem is proved for e-adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite field of q elements, the reciprocal "poles" of the zeta function are always divisible by q as algebraic integers. A p-adic proof is also given, which leads to further q-divisibiliy of the poles or equivalently an improvement of the polar part of the AxKatz theorem for an affine complete intersection. Similar results hold for a projective complete intersection.

关键词： Pole Zeta function Complete intersection