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Evaluation of Human Impacts on Bartlett Pond Ecosystem, Laredo, Southern Texas, USA, through Empirical Modeling

Journal of Environmental Protection 2024年第4期15卷 497-526页

作者： Maya P. Bhatt Amede Rubio Ganesh B. Malla cr.stobal lopez Virginia Morales Erick Vazquez Cano David Marquez Orlando Berumen Alvarez Alfred Addo-Mensah Department of Biology and Chemistry Texas A&M International University Laredo USA Department of Mathematics Computer Geology and Physics University of Cincinnati-Clermont College Batavia USA

The trace elements chemistry of Bartlett Pond, a small shallow wetland pond in Laredo, Southern Texas, was sampled to evaluate the dynamics of trace elements impacts on water quality and ecosystems ecology of the pond. Two types of fish (bass and tilapia) were also sampled to see the trace element accumulation in different parts of their body. The concentrations of trace elements in water samples were found in the following order: Fe ≫Sb > Pb > As ≫Co > Tl > cr > Cd within Bartlett Pond. Overall, the water quality of the pond is unacceptable for drinking and any other purposes as trace element concentrations (e.g. As, Cd, Co, cr, Pb, Fe, Sb and Tl) are exceedingly higher (several fold) than the WHO and US EPA guidelines. Predictive and correlation analysis shows that most trace elements exhibit a strong positive correlation among them indicating the same anthropogenic sources and biogeochemical processes regulate these trace elements within the pond. Distributions of the trace elements in water exhibit different shapes mostly as positively skewed distribution for As, Cd, Co, cr, and Tl, symmetrical distribution for Fe and almost symmetrical distribution for Pb and Sb. Concentrations of As, Co and Tl accumulated much higher in different parts of the Bass than Tilapia fish. The concentrations of As, Tl, Co, and Sb appeared significantly higher in different parts of the body of both Bass and Tilapia than the maximum SRM certified values. Accumulation of these contaminants in fish tissues pose increased health risks to humans who consume these contaminated fish although fishing is prohibited. Anthropogenic activities in the region primarily degrade the whole pond ecosystem ecology of the Bartlett Pond and waters of this pond to be not recommended for any use. These findings may be useful for the scientific community and concerned authorities to improve understanding about these precious natural resources and conservation of the ecosystem ecology.

关键词： Trace Elements Bartlett Pond Laredo Southern Texas Wetlands Ecosystem Ecology

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Dermic-derived fibroblasts for the study of amyotrophic lateral sclerosis

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Neural Regeneration Research 2020年第11期15卷 2043-2044页

作者： Javier Riancho Sara Arozamena Adolfo lopez de Munain Service of Neurology Hospital Sierrallana-IDIVALTorrelavegaSpain Department of Medicine and Psychiatry University of CantabriaSantanderSpain Centro de Investigacion en Red de Enfermedades Neurodegenerativas Instituto Carlos IIIMadridSpain Neurosciences Area Biodonostia Research InstituteService of NeurologyHospital Universitario DonostiaDepartment of NeurosciencesSchool of Medicine and NurseryUniversity of the Basque CountrySan SebastianSpain

Among neurodegenerative diseases,amyotrophic lateral sclerosis(ALS)is the most frequent one involving motor neurons(MNs).ALS incidence varies throughout the world ranging from 0.7 to 4 cases per 100,000 habitants and year(Riancho et al.,2016).This disease,which currently lacks an effective therapy,is characterized by a variable combination of upper and lower MN degeneration,leading to progressive muscle wasting which usually results in a terminal respiratory failure within 3 years after symptom onset(Zufiria et al.,2016).A small proportion of ALS cases show familial *** are related to mutations in specific causative genes(cr9ORF72,TARDBP,FUS,SOD1 and others)which directly determine disease onset in *** contrast,more than 90 percent of cases are considered to be sporadic,in which generally unknown environmental and internal factors interact with genetic predisposing factors finally leading to disease(Riancho et al.,2018).From a histopathological point of view,ALS is characterized by MN damage and *** from ALS sporadic and most of familial patients exhibit prominent transactive response DNA-binding protein 43(TDP-43)cytoplasmic aggregates which are considered as the“pathological hallmark”of the disease,excepting those related to SOD1 and FUS mutations(Zufiria et al.,2016).TDP-43 is a DNA/RNA binding protein encoded by the TARDBP gene that controls the expression of many different genes.

关键词： al. amyotrophic degeneration

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Surface Modification by Nitrogen Plasma Immersion Ion Implantation on Austenitic AISI 304 Stainless Steel

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Journal of Iron and Steel Research International 2016年第4期23卷 380-384页

作者： Miguel CASTRO-COLIN William DURRER Jorge A. lopez Enrique RAMIREZ-HOMS Max Plank Institute for Intelligente Systems Stuttgart 70569Baden-wurttembergGermany Physics Department University of TexasEl Paso TX79968-0515TexasUSA

Surfaces of AISI 304 austenitic stainless steel plates nitrided by plasma immersion ion implantation （PⅢ） technology were studied by means of Auger electron spectroscopy （AES） and X-ray photoelectron spectroscopy （XPS） to determine the effect of the nitriding process on the surface and subjacent layers. Elemental compositions obtained by AES and XPS at varying depths indicate that the saturation of N is relatively constant as a function of depth, indicating the reliability of PⅢ technology for substirface saturation. It is concluded that the concentrations of both cr and O increase with depth, the subjacent oxide is driven by the Ar^＋ sputtering process used to access the lower layers, and then N is bound to cr.

关键词： PⅢ technology AISI 304 XPS AES surface modification

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Land-use change and windstorms legacies drove the recolonization dynamics of laurel forests in Tenerife, Canary islands

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Forest Ecosystems 2023年第1期10卷 113-124页

作者： Vicente Rozas Maria A.Garcia-lopez Jose M.Olano Gabriel Sanguesa-Barreda Miguel Garcia-Hidalgo Susana Gomez-Gonzalez Roberto lopez-Rubio Jose M.Fernandez-Palacios Ignacio Garcia-Gonzalez Laura Lozano-lopez Paula Garcia-Gonzalez Ana I.Garcia-Cervigon EiFAB-iuFOR Universidad de ValladolidCampus Duques de Soria42004SoriaSpain Departamento de Biologia-IVAGRO Universidad de CadizCampus Rio San Pedro11510Puerto RealSpain Center for Climate and Resilience Research(cr)2 Blanco Encalada 20028370449SantiagoChile Area de Biodiversidad y Conservacion Universidad Rey Juan Carlosc/Tulipan s/n28933MostolesSpain Grupo de Ecologia y Biogeografia Insular Universidad de La Laguna38206La LagunaTenerifeSpain BIOAPLIC Departamento de BotanicaEscola Politecnica Superior de EnxenariaCampus TerraUniversidade de Santiago de CompostelaLugo27002Spain

Laurel forests are quite relevant for biodiversity conservation and are among the island ecosystems most severely damaged by human *** the past,Canary laurel forests have been greatly altered by logging,livestock and *** remains of laurel forests are currently protected in the Canary Islands(Spain).However,we miss basic information needed for their restoration and adaptive management,such as tree longevity,growth potential and responsiveness to natural and anthropogenic *** dendrochronological methods,we studied how forest dynamic is related to land-use change and windstorms in two well-preserved laurel forests on Tenerife *** cores were collected from over 80 trees per stand at three stands per *** used ring-width series to estimate tree ages and calculate annual basal area increments(BAI),cumulative diameter increases,and changes indicative of released and suppressed *** tree species were found in all stands,with Laurus novocanariensis,Ilex canariensis and Morella faya being the most common *** some individuals were over 100 years old,61.8%-88.9% of the trees per stand established between 1940 and 1970,coinciding with a post-war period of land abandonment,rural exodus and the onset of a tourism *** trees have shown growth rates larger than 1 cm diameter per year and most species have had increasing BAI trends over the past *** growth releases occurred after windstorms at both sites,but the effects of windstorms were site-dependent,with the 1958 storm affecting mainly the eastern tip of the island(Anaga massif)and the 1991 storm the western tip(Teno massif).Given the great ability of laurel forest trees to establish after land use cessation and to increase growth after local disturbances such as windstorms,passive restoration may be sufficient to regenerate this habitat in currently degraded areas.

关键词： Canary islands Dendroecology Disturbance Forest structure Macaronesia Management cessation Tree rings

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Chromium Differentially Affects Hydrogen Peroxide Distribution in Primary and Adventitious Roots of Arabidopsis thaliana L.

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Phyton-International Journal of Experimental Botany 2020年第1期89卷 35-43页

作者： Aaron Giovanni Munguia-Rodriguez Jose lopez-Bucio Gerardo Rangel Sanchez Leon Francisco Ruiz-Herrera Yazmin Carreon-Abud Miguel Martinez-Trujillo Instituto de Investigaciones Quimico-Biológicas Universidad Michoacana de San Nicolas de HidalgoEdificio B3Ciudad UniversitariaC.P58030MoreliaMichoacanMexico Facultad de Biologia Universidad Michoacana de San Nicolas de Hidalgo.Edificio RCiudad UniversitariaC.P58030 MoreliaMichoacanMexico

The post-embryonic growth of the Arabidopsis thaliana root system can be modified by different types of stress,such as sublethal concentrations of metals,which may induce the production of reactive oxygen species(ROS).In this study,the effects of different concentrations of potassium chromate(K_(2)crO_(4))on the distribution and relative quantity of hydrogen peroxide(H_(2)O_(2))were determined in primary and adventitious roots in *** HyPer line *** line has a biosensor that specifically reports H_(2)O_(2) levels within tissues as *** root growth was inhibited at 100μM cr(VI);in contrast,adventitious root formation was induced over the main root growth *** structures proliferated from 100-160μM cr(VI),and much higher concentrations(180-200μM)of K_(2)crO_(4) were required to affect their *** H_(2)O_(2) distributions were observed in the columella and lateral root cap of primary roots of plants grown in medium lacking dichromate,but following the development of toxicity symptoms,H_(2)O_(2) changed its distribution to the meristem and differentiation ***,adventitious roots had comparable H_(2)O_(2) distribution patterns in untreated plants and those exposed to cr(VI)***,differential H_(2)O_(2) distribution correlates with the resistance of adventitious roots,but not primary roots,to dichromate and underlies cell reorganization at the apex to support growth.

关键词： Chromate hydrogen peroxide root growth meristem ion toxicity adaptation

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水解阳离子对滑石天然疏水性的影响

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国外非金属矿与宝石 1989年第1期 18-21页

作者： M.C.Fuerstenau A.lopez-Valbrviieso 武汉工大北京研究生部

微量浮选和电动电位研究表明,水解金属阳离子在滑石表面非极性晶面和极性棱角上吸附作用的影响是不同的。虽然存在Al、cr、Fe羟基络合物,但滑石的天然可浮性不变。不过由于这些络合物在滑石极性表面上强烈吸附,滑石ζ电位的符号由负变... 详细信息

微量浮选和电动电位研究表明,水解金属阳离子在滑石表面非极性晶面和极性棱角上吸附作用的影响是不同的。虽然存在Al、cr、Fe羟基络合物,但滑石的天然可浮性不变。不过由于这些络合物在滑石极性表面上强烈吸附,滑石ζ电位的符号由负变正。在pH值低于金属氢氧化物的零电点(PZC)金属氢氧化物在非极性表面的沉积作用,使非极性表面变得亲水,可能是由于金属沉淀物在极性和非极性表面的多相凝聚作用所致。（共4页)

关键词：滑石疏水性水解阳离子浮选

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Evaluation of curcumin and copper acetate against Salmonella Typhimurium infection,intestinal permeability,and cecal microbiota composition in broiler chickens

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Journal of Animal Science and Biotechnology 2021年第3期12卷 1019-1030页

作者： Anaisa ALeyva-Diaz Daniel Hernandez-Patlan Bruno Solis-cruz Bishnu Adhikari Young Min Kwon Juan D.Latorre Xochitl Hernandez-Velasco Benjamin Fuente-Martinez Billy M.Hargis Raquel lopez-Arellano Guillermo Tellez-Isaias Departamento de Medicina y Zootecnia de Aves Facultad de Medicina Veterinaria y ZootecniaUNAM04510 Ciudad de MexicoMexico Laboratorio 5:LEDEFAR Unidad de Investigacion MultidisciplinariaFacultad de Estudios Superiores(FES)CuautitlanUniversidad Nacional Autonoma de Mexico(UNAM)54714 Cuautitlan IzcalliMexico Department of Poultry Science Center of Excellence for Poultry ScienceUniversity of Arkansas1260 W.MaplePOSC 0-114FayettevilleAR 72704USA Centro de Ensenanza Investigacion y Extension en Produccion AvicolaFacultad de Medicina Veterinaria y ZootecniaUNAMCiudad de MexicoMexico

Background:Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial *** of the most studied groups are polyphenolic compounds,given their advantages over other types of additives and their easy potentiation of effects when complexes are formed with metal ***,the objective of the present study was to evaluate the impact of dietary supplementation of copper acetate(CA),curcumin(cr),and their combination(CA-cr)against Salmonella Typhimurium colonization,intestinal permeability,and cecal microbiota composition in broiler chickens through a laboratory Salmonella infection *** recovery was determined on day 10 post-challenge by isolating Salmonella in homogenates of the right cecal tonsil(12 chickens per group)on Xylose Lysine Tergitol-4(XLT-4)with novobiocin and nalidixic *** integrity was indirectly determined by the fluorometric measurement of fluorescein isothiocyanate dextran(FITC-d)in serum samples from blood obtained on d 10 *** ***,microbiota analysis was performed using the content of the left caecal tonsil of 5 chickens per group by sequencing V4 region of 16S rRNA ***:The results showed that in two independent studies,all experimental treatments were able to significantly reduce the *** colonization in cecal tonsils(CT,Pcr was the most effective treatment in reducing *** counts in both independent ***,the serum fluorescein isothiocyanate dextran(FITC-d)concentration in chickens treated with cr was significantly lower when compared to PC(P=0.0084),which is related to a decrease in intestinal permeability and therefore intestinal *** effect of dietary treatments in reducing Salmonella was further supported by the analysis of 16S rRNA gene sequences using Li

关键词： Broiler chickens Copper acetate Curcumin Intestinal permeability Microbiota composition Salmonella Typhimurium

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Alloying OCTG pipes with tungsten

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Baosteel Technical Research 2010年第S1期4卷 65-页

作者： F DAGUERRE G lopez TURCONI J C GONZALEZ Product Development Tenaris Dr.A.Simini 250(2804) CampanaBuenos AiresArgentina

The mechanical and corrosion performance of low alloy steel tubular goods depends on the microstructure obtained as a result of the combination of alloying elements and manufacturing process parameters. The basic design philosophy for the selection of the alloying elements is ruled by the balance between the steel cost and the material *** this approach the alloying sequence for the manufacturing of tubular components in oil country tubular goods(OCTG) application is generally Mn,C,r and Mo,used as substitutional elements in a total added weight concentration around 1%up to 3%.Other elements such as B,Ti,Nb and V are applied as strengthening microalloying elements forming fine precipitates. A lack of experience is found related to the use of Tungsten(W) on OCTG applications,although W is also a substitutional element that belongs to group 6 of the periodic table together with cr and *** the other hand W is widely added for steel pipes working in high temperature services such as power plant boilers,where creep resistance is *** is also applied for tool steels enhancing the hardness,wear resistance and cutting performance. Taken into consideration the similarity between cr,Mo and W and the applications where W has been proven it was decided to analyze the feasibility of using W as an alternative alloying element for some OCTG applications. Another factor that drives this study is the fact that W could be a cost effective substitute of Mo,depending on the alloy market price. This paper is based on literature review and experimental activity done on laboratory steels in which 0.1%Mo was replaced by 0.2%and 0.4%*** different findings in regards with manufacturing process considerations, material performance and the possible use of W alloyed steel for OCTG applications are summarized. (1 ) Opposed to the susceptibility shown by low carbon with high cr-W content,hot cracks are not expected in medium C steels(0.2%-0.3%) with W addition up to 1%.

关键词： oil country tubular goods(OCTG) alloying elements tungsten low alloy steel corrosion resistant microstructure

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Evaluation of Effect of Eddy Currents in PLC Influenced by Atmospheric Corrosion in the Electronics Industry

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材料科学与工程（中英文B版） 2013年第5期3卷 314-321页

作者： Gustavo lopez Badilla Elizabeth Romero Samaniego Sandra Luz Toledo Perea Miriam Maleny Garcia Castrellon Luis Alberto Gameros Rios Researcher-Academic Technological Institute of Mexicali (TIM) Mexicali Baja California M~xico Researcher-Academic Technological Institute of Ensenada (TIE) Ensenada Baja California Mexico Students of Electronic Engineering Technological Institute of Mexicali (TIM) Mexicali B.C. M~xico

Inductive proximity sensors contain an internal coil. When a current flow through it, a magnetic field is generated, which has the direction of the electric currents involved in it, as electrical flow in the input or output area. The coil or winding of the inductive sensor induces Foucault currents in the material to be detected, that are originated by eddy currents. These electrical flows generate a magnetic field, which opposes to the sensor coil, causing a reduction in the inductance of micro inductors of electronic devices. This reduction of the internal inductance originates bad function in the micro inductors used in the programming logic controller (PLC). This PLC is in the manufacturing processes of the electronics industry and reduces their operation yielding. Sometimes the actuators of these electronic systems not operate correctly, and causing stops in the activities of industrial equipments and machines, being a factor of economic losses. A study of micro evaluation of these inductors which are elements of the relays of PLC was made to determine the influence of corrosion in these components. The analysis showed micro corrosion in these devices with images obtained of the scanning electron microscopy (SEM) and also was made a correlation of the climatic factors as relative humidity (RH) and temperature with the corrosion rate (cr). The evaluation was made in indoor of an industrial plant which fabricate microelectronic components in Mexicali city. The major factors, which cause an adverse effect in the operation of PLC of this industrial plant was the humidity and sulfurs, which originates the deterioration of components of PLC. The study was made from 2010 to 2011.

关键词：大气腐蚀 PLC 电子工业影响评估涡流电感式传感器接近传感器相对湿度

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Magnetism of cr Impurities Embedded in Cu fcc Matrix： Density Functional Calculations

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材料科学与工程（中英文B版） 2014年第8期4卷 262-267页

作者： Juan Ulisses Gallardo Zazueta Raul Enrique Felix Medina Manuel Andres Leyva Lucero Ricardo Alberto Guirado lopez Salvador Meza Aguilar Instituto de Fisica Manuel Sandoval Vallarta Universidad Aut6noma de San Luis PotosL San Luis Potos~ San Luis Potosi 78290MOxico Facultad de Ciencias Fisico-Matematicas Universidad A utonoma de Sinaloa Culiaean Sinaloa 80010 Mexico

We present extensive first principles density functional theory (DFT) calculations dedicated to analyze the magnetic properties of crn (n = 2 and 3) impurities embedded in a Cu fcc matrix. We consider several dimers and trimers having different interatomic distances. In all cases the cr atoms have been embedded as substitutional impurities in the metallic network. For the case of the dimers we have considered two magnetic configurations: Ferromagnetic (Antiferromagnetic) when the atomic magnetic moments are parallel (antiparallel) each other, for this case we have found that the lowest-energy state corresponds to the antiferromagnetic coupling between cr atoms whose interatomic distance is a√2. In the case of the cr trimers we have considered three or four magnetic configurations, depending on the cr impurity geometry, for this case we have found that the lowest-energy state corresponds to the antiferromagnetic cr trimer AF (↑,↓,↓) forming an isosceles right angle triangle whose hypotenuse and legs length are a√2 and a, respectively, with magnetic moments c (2) = 3.45/-3.32/3.45 μB.

关键词：密度泛函理论磁性杂质嵌入式 FCC 反铁磁耦合等腰直角三角形铬矩阵

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