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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 Cristobal 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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Positive interactions by cushion plants in high mountains:fact or artifact?

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Journal of Plant Ecology 2016年第2期9卷 117-123页

作者： Marco A.Molina-Montenegro Rómulo Oses Ian S.Acuña-Rodríguez Cristian Fardella Ernesto I.badano Patricio Torres-morales Jorge Gallardo-Cerda Cristian Torres-Díaz Instituto de Ciencias biológicas Universidad de TalcaAvda.Lircay s/nTalcaChile Centro de Estudios Avanzados en ZonasÁridas(CEAZA) Facultad de Ciencias del MarUniversidad Católica del NorteCoquimboChile División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaCamino a la Presa San José2055Colonia Lomas ta Sección CP 78216San Luis PotosíSLPMéxico 4 Instituto de Ciencias Ambientales y EvolutivasUniversidad Austral de ChileValdiviaChile Departamento Científico Instituto Antártico Chileno(INACH)Punta ArenasChile Laboratorio de Genómica y biodiversidad(LGb) Departamento de Ciencias NaturalesUniversidad del Bío-BíoChillánChile

Positive interactions are defined as non-trophic interactions where at least one of the interacting species is benefited in terms of fitness and the other remains ***,the bidirectional feedbacks between species may be positive,neutral or ***,if facilitated species induce negative effects on their‘nurses’,the assumed definition of positive interactions could be *** We assessed if ecological interactions between cushions of Azorella madreporica and their facilitated species are ***,we tested if cover of facilitated species has any costs for cushion plants from an ecophysiological perspective,and if these costs increase with the amount of cover of facilitated *** addition,through pathway analysis and correlations,we assessed if cover and richness of facilitated species have a direct and/or indirect effect on the fitness of cushion *** Findings We found that facilitated plant species induced a significant cost for their nurses(cushion plants),and this cost increases with cover of the facilitated ***,the facilitated species exert a strong direct negative effect on the cushion’s fitness and a moderate indirect negative cost evident through the nutrient status and physiological performance of cushion *** thus contribute evidence that positive interactions between high mountain cushion plants of central Chile and their‘facilitated’species may be an artifact more than a fact,especially when bidirectional effects are considered;contrasting with the majority of studies that document only one side of the interaction.

关键词： cushion plants facilitation nurse effect positive interactions stress gradient hypothesis

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Ab InitioMolecular Orbital Calculation for Optical and Electronic Properties Evaluation of Small and Medium Size Silicon Nano-Clusters Found in Silicon Rich Oxide Films

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Journal of Modern Physics 2013年第11期4卷 1-26页

作者： Néstor David Espinosa Torres José Francisco Javier Flores Gracia José Alberto Luna López Juan Carlos Ramírez García Alfredo morales Sánchez José Luis Sosa Sánchez David Hernández de la Luz Francisco morales morales Research Center for Advanced Materials S.C. Unit Monterrey-PIIT Apodaca México Research Center for Semiconductor Devices CIDS-ICUAP-BUAP Puebla México The Faculty of Chemical Sciences BUAP Puebla México

In systems in atomic and nano scales such as clusters or agglomerates constituted of particles from a few to less than one hundred of atoms, quantum confinement effects are very important. Their optical and electronic properties are often dependent on the size of the systems and the way in which the atoms in these clusters are bonded. Generally, these nano-structures display optical and electronic properties significantly different of those found in corresponding bulk materials. Silicon agglomerates found in Silicon Rich Oxide (SRO) films have optical properties, which have reported as depended directly on nano-crystal size. Furthermore, the room temperature photoluminescence (PL) of Silicon Rich Oxides (SRO) has repeatedly generated a huge interest due to their possible applications in optoelectronic devices. However, a plausible emission mechanism has not yet widespread acceptance of the scientific community. In this research, we employed the Density Functional Theory with a functional b3LYP and a basis set 6 - 31G* to calculate the optical and electronic properties of small (six to ten silicon atoms) and medium size clusters of silicon (constituted of eleven to fourteen silicon atoms). With the theoretical calculation of the structural and optical properties of silicon clusters, it is possible to evaluate the contribution of silicon agglomerates in the luminescent emission mechanism experimentally found in thin SRO films.

关键词： Nano-Crystals Silicon Clusters Silicon-Rich Oxide Luminescence Magic-Number

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Protective effect of some vitamins against the toxic action of ethanol on liver regeneration induced by partial hepatectomy in rats

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World Journal of Gastroenterology 2008年第6期14卷 899-907页

作者： Carlett Ramírez-Farías Eduardo Madrigal-Santillán José Gutiérrez-Salinas Nidia Rodríguez-Sánchez Maricela Martínez-Cruz Ilse Valle-Jones Ingrid Gramlich-Martínez Alejandra Hernández-Ceruelos José A morales-González Unidad de Genética de la Nutrición Instituto Nacional de Pediatría México Instituto de Ciencias de la Salud Universidad Autónoma del Estado de Hidalgo México Laboratorio de bioquímica y Medicina Experimental Unidad de Investigación Biomédica División de Investigación Centro Médico Nacional "20 de Noviembre" ISSSTE México Gatorade Sports Science Institute Mexico City México Escuela de Dietética y Nutrición ISSSTE México University of Ryerson Toronto

AIM: To investigate the effects of vitamins (A, C and E) on liver injury induced by ethanol administration during liver regeneration in rats. METHODS: Male Wistar rats subjected to 70% partial hepatectomy were divided into five groups (groups 1-5). During the experiment, animals of Group 1 drank only water. The other four groups (2-5) drank 30 mL of ethanol/L of water. Group 3 additionally received vitamin A, those of group 4 vitamin C and those of group 5 received vitamin E. Subsequently serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin and bilirubin were measured colorimetrically. Lipid peroxidation (thiobarbituric-acid reactive substances, TbARS) both in plasma and liver was measured, as well as liver mass gain assessment and total DNA. RESULTS: Compared with sham group, serum AST and ALT increased significantly under ethanol treatment (43% and 93%, respectively, with P bumin concentration compared to sham group (3.1 ± 0.4 g/dL vs 4.5 ± 0.2 g/dL; P both hepatic and plasma lipid peroxidation. Vitamins (C and E) treatment attenuated hepatic and plasma lipid peroxidation. CONCLUSION: Vitamins C and E protect against liver injury and dysfunction, attenuate lipid peroxidation, and thus appear to be significantly more effective than vitamin A against ethanol-mediated toxic effects during liver regeneration.

关键词： Lipid peroxidation Antioxidant vitamins Alcohol-induced liver injury Liver regeneration

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Catalytic Performance of La0.6Ca0.4Fe1-xNixO3Perovskites in DME Oxidation

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Modern Research in Catalysis 2015年第4期4卷 97-106页

作者： Gina Pecchi Ruddy morales Daniela Salinas Eduardo J. Delgado José Luis García Fierro Facultad Ciencias Químicas Universidad de Concepción Concepción Chile Instituo Catálisisy Petroleoquímica CSIC Cantoblanco Madrid Spain

Substituted La0.6Ca0.4Fe1-xNixO3 (0.0 ≤ x ≤ 1.0) perovskite-type oxides prepared by the amorphous citrate method have been investigated as catalysts in the dimethyl ether (DME) oxidation reaction. The samples with an x ≤ 0.3 composition show an orthorhombic structure, while the intermediate compositions with 0.5 ≤ x ≤ 0.9 show a less crystalline orthorhombic perovskite structure with segregated phases that increase upon increasing the Ni content. The progressive substitution of Fe3+ by Ni2+ in La0.6Ca0.4FeO3 entails the progressive formation of oxygen vacancies and Fe4+ species for Ni substitution degrees of x ≤ 0.5. For larger degrees of substitution with x > 0.7, segregated phases and a progressive loss of the perovskite structure are detected. The highest catalytic performance for the total combustion of DME is obtained from equimolar substitution in the b-site position (Fe0.5Ni0.5), in which a large extent of Fe4+ species and oxygen vacancies are present.

关键词： DME Perovskites Oxidation Iron Nickel

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PGE2Generation in Myocardium from Isolated Rat Atrium under Hypoxia and Reoxygenation Conditions. Effect of Anti-β1IgG from Patients with Chronic Severe Periodontitis

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Pharmacology & Pharmacy 2014年第2期5卷 204-215页

作者： Sabrina Ganzinelli Silvia Reina Mirian Matoso Germán González Celina morales Enri borda Institute of Cardiovascular Physiopathology School of Medicine University of Buenos Aires Buenos Aires Argentina National Research Council of Argentina (CON-ICET) Buenos Aires Argentina Institute of Cardiovascular Physiopathology School of Med-icine University of Buenos Aires Buenos Aires Argentina Pharmacology Unit School of Dentistry Uni-versity of Buenos Aires Buenos Aires Argentina National Research Council of Argentina (CON-ICET) Buenos Aires Argentina

background: Hypoxia is one of the most frequently encountered stresses in health and disease. Methods: We compared the effects of an anti-β1 periodontal IgG (pIgG) and an authentic β1 adrenergic agonist, xamoterol, on isolated myocardium from rat atria contractility. We used an ELISA assay to measure the generation of PGE2 in vitro after the addition of either the antibody or the adrenergic agonist. We analyzed the myocardium histopathologically in the presence of both the antibody and/or the adrenergic agonist drug during normoxia, hypoxia and reperfusion conditions. Results: PGE2 generation increased during the hypoxia and was unchanged during reoxygenation period compared with the production of this prostanoid in atria during normoxia condition. A β1 specific adrenoceptor antagonist atenolol and the β1 synthetic peptide abrogated the increment of the prostanoid in the presence of pIgG but only atenolol due to it in the presence of xamoterol. The increment of PGE2 was dependent on the activation of cox-1 and cox-2 isoforms. Moreover, cox-2 was more active and produced more increments in the production of PGE2 in the presence of the pIgG than cox-1 activation. Histopathologically, studies of myocardium specimens during these different periods of the experimental protocol: basal (b), hypoxia (H) and reoxygenation (R), were also performed and showed tissue necrosis and edematization at the myocardium level. Conclusion: The phenomenon studied here supports the notion that PGE2 may be responsible for tissue edematization. PGE2 maybe acts as a beneficial modulator in the myocardium and prevents a major injury of it. The inflammation damage to the heart organ and cardiomyocytes caused by the actions of the antibodies in the course of heart lesions provoked by cardiovascular autoimmune disease, explains some of these results obtained in the present experiments. Further studies will be needed to establish the real role of PGE2 during hypoxia injury of the heart in the cour

关键词： Myocardium PGE2 Hypoxia Histopathology Periodontitis Antibodies Anti-β1 Adrenoceptors Xamoterol

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Innovate combination of sevoflurane dilution in dimethyl sulfoxide: A stability study by gas chromatography and nuclear magnetic resonance

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World Journal of Pharmacology 2016年第3期5卷 59-67页

作者： F Dámaso Fernández-Ginés Sergio García-Mu?oz Héctor Mateo-Carrasco Miguel ángel Rincón-Cervera manuel Corti?as-Sáenz José Antonio morales-Molina Carmen Fernández-Sánchez Juan Miguel Expósito-López Ignacio Rodríguez-García Department of Pharmacy Torrecárdenas Hospital University of Almería Aseptic Services Unit Department of Pharmacy Northampton General Hospital Institute of Nutrition and Food Technology University of Chile Department of Anesthesiology and Pain Management Torrecárdenas Hospital Department of Pharmacy Agencia Pública Empresarial Sanitaria Hospital de Poniente Department of Chemistry and Physics University of Almería

To investigate physicochemical stability of sevofuranein dimethyl sulfoxide using gas chromatography with a fame ionization detector and nuclear magnetic reso-nance （NMR）.METHODSUndiluted sevoflurane, plus dilutions 1：2, 1：5, 1：10, 1：25, and 1：50 in dimethyl sulfoxide were prepared in a vertical laminar fow cabinet class Ⅱ type b and stored at different temperatures （23 ℃, 6 ℃, and -10 ℃） for 45 d. Sterile 1 mL polypropylene amber syringes to minimize light degradation, caps and needles were used. The presence of sevofurane and its degradation products in the samples was determined by gas chroma-tography with flame ionization detector （260 ℃, 40min）, and by 1H, 19F, and proton-decoupled 19F nuclearmagnetic *** The gas chromatography analysis showed sevofluraneand dimethyl sulfoxide （DMSO） retention times were 2.7and 13.0 min, respectively. Pure DMSO injection into thecolumn resulted in two additional peaks at 2.1 and 2.8min. The same sevofurane peak at 2.7 min was observedin all the dilutions at -10 ℃, 4 ℃ and 25 ℃. The NMRspectra showed signals consistent with the sevoflurane structure in all the dilutions at -10 ℃, 4 ℃ and 25 ℃. In the 1H spectrum, two signals corresponding to the sevoflurane molecule were observed at 5.12 and 4.16 parts per million （ppm5）. In the 19F-NMR spectrum, two signals were observed at -76.77 ppm and -157.13 ppm. In the 19F NMR CPD, two signals were observed at -76.77 ppm and -157.13 ppm. The first one showed a doublet （JF-F = 3.1 Hz） which integrated by six fluorine nuclei from the hexafluoro-isopropyl group. The second signal was integrated by a fuorine atom and showed a septuplet （JF-F = 3.1 Hz）.CONCLUSIONThis study shows that different concentrations ofsevofurane in dimethyl sulfoxide retain their chemicalcomposition after exposure to different temperaturesfor a period of 45 d.

关键词： Sevoflurane Dimethyl sulfoxide Uclear magnetic resonance Gas chromatography Skin ulcers Drug stability

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Rare-Earth Doped GdVOb>4b> by Sol-Gel Method: Structural and Luminescence Properties

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World Journal of Engineering and Technology 2022年第4期10卷 907-922页

作者： D. Y. Medina-Velázquez A. D. J. morales-Ramírez A. A. morales-Hernández b. Gonzalez L. Ramírez-García E. Garfías-García J. Oliva C. R. Garcia J. Reyes-Miranda M. A. barron E. Osorio-de-la-Rosa Universidad Autónoma Metropolitana-Azcapotzalco Ciencias Básicas e Ingeniería Reynosa México Instituto Politécnico Nacional CIITEC IPN Cerrada de CECATI S/N Col. México City México Instituto Politécnico Nacional ESIQIE IPN México City México CONACyT-División de Materiales Avanzados Instituto Potosino de Investigación Científica y Tecnológica A. C. San Luis Potosí México Facultad de Ciencias Físico Matemáticas Universidad Autónoma de Coahuila Edif. A Unidad Camporredondo Saltillo México Comonfort Col. Del bosque. C.P. 77019 Chetumal Quintana Roo México.6 CONACYT-Universidad Autónoma del Estado de Quintana Roo Boulevard Bahía s/n esq. Ignacio Chetumal México

Rare earths have been extensively developed in recent years, however, new hosts allow high excitation and emission efficiency, in this sense, gadolinium vanadate has been extensively studied and in previous works it has been widely used in down conversion systems. because of the strong absorption of the VO4b> groups and efficient energy transfer from GdVO4b> to lanthanide ions, in this work its up-conversion properties were studied when is co-doped with Yb3+, X3+ where X = Tm, Er and Ho. The powders synthesized presented a high crystallinity and a rounded morphology and exhibit a high luminescence when are excited with IR radiation.

关键词： Gadolinium Rare Earths Up Convertion

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Synthesis of Tenoltrifluoroacetone Composite Doped with Terbium, Dysprosium and Europium Encapsulated in Silica Oxide Matrix

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Journal of Surface Engineered Materials and Advanced Technology 2020年第4期10卷 63-74页

作者： Yazmin Francisco Dulce Medina Miguel barron Joan Reyes Pedro Adrian Martinez Angel de Jesus morales Elizabeth Garfias Universidad Autónoma Metropolitana Departamento de Materiales Ciencias Básicas e Ingeniería Reynosa Tamaulipas México Instituto Politécnico Nacional ESIQIE UPALM S/N Mexico City México

The synthesis of the thenoyltrifluoroacetone compound doped with terbium, dysprosium and europium encapsulated in a silica matrix (TTA:Tb:Dy:Eu@SiO2) were performed by the sol-gel method. The precursors to obtain the ... 详细信息

The synthesis of the thenoyltrifluoroacetone compound doped with terbium, dysprosium and europium encapsulated in a silica matrix (TTA:Tb:Dy:Eu@SiOb>2b>) were performed by the sol-gel method. The precursors to obtain the vitreous phase (SiOb>2b>) were: Tetraethylorthosilicate (TEOS, Cb>8b>Hb>2b>Ob>4b>Si, 98%, Aldrich), and ethyl alcohol (CHb>3b>CHb>2b>OH, 99.5%, Meyer), distilled water and 0.05 ml of hydrochloric acid (HCl, Meyer). The sample with molar ratio 20:80 TTA:Tb:Dy:Eu@SiOb>2b> has the best emission intensity. Thermogravimetric analysis (TGA) shown that silica encapsulated samples decompose at lower temperatures than pure TTA:Tb:Dy:Eu luminescent material. Fourier Transform Infrared (IR-TF) shown the characteristic Si-O-Si bands that are presented at a wavelength of 1049, 853 and 440 cmǃ confirming that the luminescent material is encapsulated in a silica matrix, finally X-ray diffraction (XRD) shown that TTA:Tb:Dy:Eu@SiO2 composite is amorphous.

关键词： Synthesis Luminescence Composite Sol-Gel Terbium Dysprosium and Europium

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Red, White and blue Light Emission from Europium Doped Al2O3 Confined into a Silica Matrix

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Open Journal of Applied Sciences 2018年第8期8卷 338-345页

作者： Joan Reyes Dulce Y. Medina Miriam Aguilar Miguel A. barron Elizabeth Garfias Angel de Jesus morales Ciencias básicas e Ingeniería Universidad Autónoma Metropolitana-Azcapotzalco Reynosa México Instituto Politécnico Nacional ESIQIE Mexico City México

The main drawbacks of fluorescent activated lanthanide luminescent materials in practical optoelectronic applications are the high cost of raw material and the limitation of a specific color depending on the lanthanide ion. In this work, the synthesis of red, white and blue light emitting composite powders of Al2O3:Eu3+@SiO2 were successfully synthesized by the hydrolysis and condensation reactions of TEOS as the raw precursor of silica matrix on the Al2O3:Eu3+ surface. With the aim to change the CIE coordinates different weight ratios of Al2O3:Eu3+/SiO2 powders from 13Al/87Si to 5Al/95Si were prepared. besides, various excitation wavelength from 280 to 340 nm was used in order to change the ratio intensity;Ired/Iblue, between the red emission coming from the 5D0→7F2 transition of Eu3+ ions and the blue band of silica matrix. Chemical evolution of the hydrolysis and condensation reaction of TEOS were conducted by FTIR spectroscopy. The results indicate that from 500°C a complete TEOS to SiO2 transformation is carried out.

关键词： Luminescent Lanthanide Luminescence White Emission Aluminium Oxide

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