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Influenza of the Cu Ion on the Structural and Optical Properties in Cu + Ce Co-Doped ZnO Compounds

World Journal of Condensed Matter Physics 2017年第2期7卷 47-55页

作者： S. López-Romero M. J. Quiroz Jiménez M. García-Hipólito J. ch.vez-Ramírez Departamento de Materia Condensada y Criogenia Universidad Nacional Autónoma de México Instituto de Investigaciones en Materiales Ciudad de México Mexico

This article showed and explained the effects of the Cu2+ ions on the structural and photoluminescent properties of Ce3+ doped ZnO compounds (ZnO: Ce3+) in Cu2+ + Ce3+ co-doped ZnO (ZnO: Cu2+ + Ce3+) solid solutions powders. The samples were synthesized by a solution combustion method maintaining the Ce3+ ion concentration constant in 3%wt and varying the Cu2+ ion concentration in 0%wt, 1%wt, 2%wt, 3%wt, 10%wt and 20%wt. However, pristine ZnO and Ce3+ doped ZnO were synthesized by the same method for comparison. After the synthesis process all the samples were annealed at 900°C by 24 h. The pure ZnO, ZnO: Ce3+ and ZnO/Cu2+ + Ce3 powders were structurally characterized using X-ray diffraction (XRD) technique, the XRD patterns showed that for either undoped and doped with the Cu2+ ion both exhibited the hexagonal wurtzite ZnO crystalline structure, also the diffraction peaks of both samples types showed a little change toward lesser angles. The morphology and particle size of the samples were observed by means of a scanner electron microscopy (SEM);from SEM imagen is observed that the crystallites of the samples are agglomerated forming cage-like hollow structures caused by the combustion process. The cage-like structures have approximate size of 800 nm. In addition, the photoluminescence of pure ZnO, ZnO: Ce3+and ZnO: Cu2+ + Ce3+ compounds was measurement as a function of Cu2+ ion concentration under a excitation wavelength of 378 nm in the UV region. As an important result, it is observed that by Auger phenomena of non-radiative recombination, the UV emission of the ZnO is quenching.

关键词： Zinc Oxide Copper-Cerium Co-Doped Solution-Combustion

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Body Image Anxiety on University Students (Differences between Men and Women)

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Open Journal of Medical Psychology 2014年第5期3卷 348-354页

作者： Humberto Blanco Vega Juan Francisco Aguirre ch.vez Judith Margarita Rodríguez-Villalobos José René Blanco Ornelas Héctor Luis Medina López Faculty of Physical Culture Sciences Autonomous University of Chihuahua Chihuahua México

The aim of this research lies on comparing anxiety body image profiles between male and female university students. A total sample of 2089 freshmen—902 women and 1187 men is from the different degrees offered by the Autonomous University of chihuahua, with an average age of 18.23 ± 0.74 years. The approach used in the research is part of a quantitative design with a survey description. The differences found between men and women regarding their own perception of anxiety suggest that when designing any kind of intervention that aims at the decreasingly perceived anxiety, the gender variable will have to be taken into account. Future investigations should respond to these discoveries in larger samples.

关键词： Students’ Beliefs Gender Differences Higher Education Academic Performance Students’ characteristics

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Potential Species Distribution and Richness of Ixodidae Ticks Associated with Wild Vertebrates from Michoacán, Mexico

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Journal of Geographic Information System 2014年第5期6卷 467-477页

作者： Margarita Vargas-Sandoval Angel G. Priego-Santander Alejandra Larrazábal Carolina G. Sosa-Gutiérrez Blanca Lara-ch.vez Teresita Avila-Val Facultad de Agrobiología “Presidente Juárez” Universidad Michoacana de San Nicolás de Hidalgo Uruapan México Centro de Investigaciones en Geografía Ambiental UNAM Antigua Carretera a Pátzcuaro No. 8701 ExHacienda de San José de la Huerta Morelia México Unidad de Investigación Médica de Enfermedades Infecciosas y Parasitarias Hospital de Pediatría Centro Médico Nacional Siglo XXI México DF México

Ticks are regarded as the most relevant vectors of disease-causing pathogens in domestic and wild animals. The diversity of Ixodidae is known for a very small number of ***?are represented by 26 species, and?in?2007 the first reported ticks vectors in Mexico for the causal agent of Lyme disease. Recent rise in tick-borne disease in many parts of the world is a phenomenon in need of an explanation. The main objective of the present work was to map at a regional scale (1:2,000,000)?of?the distribution of ticks of the family Ixodidae that are potentially present on the wild fauna of state of Michoacan, Mexico. We compiled all available literature on ticks at a national level together with complete cartographic and bibliographic georeferenced information of the distribution of hosts in order to build a spatial database in ArcView 3.3. The results indicated that the wild fauna in the state’s territory could potentially include 31 species of ticks of Ixodidae. The map of potential species richness of ixodid ticks on the wild fauna of the state can be categorized into five classes of species richness. The highest potential concentration of ixodid species on wild fauna occurs in the volcanic area of Pico de Tancítaro.

关键词： Ticks Ixodidae Michoacán Geographic Distribution Potential Species Richness

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Recurrent and Invasive Primary Squamous Cell Carcinoma of the chest Wall: A Case Report

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Surgical Science 2020年第8期11卷 209-215页

作者： Corona Figueroa Alejandro Angel García Rodríguez Francisco Mario Lorenzo Silva José Manuel Corona Padilla Alejandro Arnulfo Mancera Steiner Carlos González ch.vez Alberto Manuel General Surgery Service Hospital Espa&ntilde ol de México México City México Oncology Surgery Service Hospital Espa&ntilde ol de México México City México Thoracic Surgery Service Hospital Espa&ntilde ol de México México City México Plastic Surgery Service Hospital Espa&ntilde ol de México México City México

Squamous cell carcinoma is a type of skin cancer with abnormal proliferation of keratinocytes. Its incidence reaches approximately 20% of cases of non-melanoma skin cancer, which has increased in recent decades due to growth in life expectancy, increased sun exposure, the use of tanning beds and improved detection of this type of tumors. We present a patient who was diagnosed with a squamous cell skin carcinoma in the chest wall, treated initially with surgical resection. A few years recurred in the same place, so the patient received radiotherapy with poor response. Ultimately a new surgical approach was performed with a wide margin resection by a multidisciplinary surgical team. Multidisciplinary management in this type of procedure is important so that the long-term result is optimal for the patient.

关键词： Squamous Cell Carcinoma Skin Cancer chest Wall Tumor Oncological Sternectomy

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Effect of cholesterol Enriched or Fatty-Acid Diets on cholesterol and Lipid Levels in Young Wistar Rats

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Advances in Bioscience and Biotechnology 2014年第10期5卷 846-852页

作者： Maribel Cortés-Ortiz Perla Leal-Galicia Benjamín E. ch.vez-álvarez María del Carmen Cárdenas-Aguayo Marco Antonio Meraz-Ríos Departamento de Biomedicina Molecular Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional Instituto Politécnico Nacional Mexico City Mexico

Nutritional intake is a fundamental determinant of health. It is well known that cholesterol rich diets can induce several pathological conditions but detailed mechanism underlying these remains unknown. Wistar rats, an animal strain widely used in the research have been employed to study the effects of dietary interventions due to their metabolic characteristics, which are closer to the human compared to mice. The effect of some components of the western diet, combined with cholesterol in the lipid profile have been studied, but the impact of only cholesterol or fatty-acid diets in such a profile has not been yet characterized. Here we measured the effect of 6 or 16 weeks of dietary intervention with cholesterol enriched diet (CED) or fatty-acid diet (FAD) on cholesterol, triglyceride levels, high density lipoproteins (HDL) and low density lipoproteins (LDL). We observed significant differences in body weight only in animals treated with CED or FAD from Week 9 onwards as compared to animals fed the control diet. There were no differences between animals fed with CED or FAD in cholesterol levels at any time point nevertheless, triglyceride levels were significantly increased as compared to control diet in animals under both diets at early time points. Finally, both CED and FAD induced a decrease in HDL as compared to control levels in treatments of more than 6 weeks, whereas LDL transiently increased in animals treated with FAD from 10 to 12 weeks, but after this period LDL levels returned to baseline, suggesting that young rats have a compensatory effect at least for the period of time analyzed here. Here we provide a temporal course on lipid profile of cholesterol, triglycerides, HDL and LDH in Wistar rats treated with CED and FAD diet that can be useful as reference for future studies.

关键词： cholesterol-Enriched Diet Fatty-Acid Diet cholesterol Triglycerides Young Wistar Rat

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设计工程:软性基础设施——以墨西哥城的Texcoco公园为例

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南方建筑 2015年第4期 78-85页

作者： I?aki Echeverria Adriana ch.vez 陈雨虹刘雅琦哈佛大学设计研究生院景观系哈佛大学设计研究生院北京大学深圳研究生院城市规划与设计学院同济大学建筑与城市规划学院风景园林系

在当代的新形势下,城市地区必须探索新的实践和工程模式。Texcoco生态公园是一个关于城市如何重新构想和协调土地和生态复杂性的案例。该项目位于墨西哥城的生态区内,它揭示和探究了传统的建筑学方法如何无法应对大都市区所面临的复杂... 详细信息

在当代的新形势下,城市地区必须探索新的实践和工程模式。Texcoco生态公园是一个关于城市如何重新构想和协调土地和生态复杂性的案例。该项目位于墨西哥城的生态区内,它揭示和探究了传统的建筑学方法如何无法应对大都市区所面临的复杂问题。Texcoco生态公园意在成为世界上最大的城市公园,同时设法解决当下墨西哥峡谷所面临的水危机。认识到水作为主要的组织元素,该项目提出两大主要策略来解决最具挑战性的问题。这两大策略是:"平衡"和"多任务"。这个公园同时作为一个软性基础设施,一种更加复杂的结构,而不是单一功能的支持系统。最后,该项目提出为区域未来发展所需的四个系统:栖息地系统、社会发展项目系统、交通系统和能源系统。

关键词：特斯科科湖水文地理软性基础设施雨水涵养平衡多目标

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Comparison of the Incidence of Complications among the Different Techniques of Laparoscopic Approach: Experience in a General Surgery Service in a Private Hospital

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Surgical Science 2018年第7期9卷 227-232页

作者： Mauricio Valdez-Durón Jorge Fernández-álvarez Alberto Manuel González-ch.vez Francisco ángel Vega-Romero Ketzalcoatl Tecomahua-Román Antonio García-Ruiz Hospital Españ ol de México Mexico City Mexico Hospital General Xoco Mexico City Mexico Hospital Central Militar Mexico City Mexico

Introduction: At least four techniques or approaches to minimize the risk of injury have been introduced. The correlation between techniques and the complication rate is controversial. The objective of the study is to report the incidence of laparoscopic entry associated injury, in relation to the used technique. Material and Methods: A retrospective study was conducted at the Hospital Espa? ol, in a 12-month period (2013). The medical records of all patients who underwent laparoscopic surgery were reviewed. Demographic and surgical variables were analyzed, comparing the results statistically through an analysis of variance (ANOVA). Results: A total of 792 cases were analyzed. The surgeries performed were: cholecystectomies (42%), appendectomies (26%), diagnostic laparoscopies (20%), ventral or inguinal hernioplasty (9%) and fundoplications (3%). The preferred approach was Hasson’s (79%) and Veres’s needle technique (14%), followed by classic closed (14%) and Palmer technique (2%). We documented six cases of laparoscopic entry associated injury (0.76%), four associated with the Hasson technique, one with Veress’s needle technique and one with direct approach technique were reported. The statistical analysis was performed considering the different techniques and their relation with the injuries. Analysis of variance did not reach statistical significance (p = 0.31). Conclusions: Among our data, the number of laparoscopic entry associated injuries, was less than 1%, and has a similar frequency to the reported literature. We did not find significant differences between the four laparoscopic entry techniques. There remains no clear evidence as to the optimal form of laparoscopic entry in the low-risk patient.

关键词： Laparoscopic Surgery Pneumoperitoneum Complications

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The effect of alpha asarone, olive oil, and dexamethasone on collagen-induced arthritis (CIA) in the mouse

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Modern Research in Inflammation 2013年第1期2卷 9-20页

作者： Mayda Yanik Aquino-Vega Lorena Rodríguez-Páez Patricia Arce-Paredes Víctor G. Hernández-ch.vez Enrique Becerril-Villanueva osca. Rojas-Espinosa Departamento de Bioquímica Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional México D.F. México Departamento de Inmunología Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional México D.F. México Departamento de Inmunología Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional México D.F. México Departamento de Morfología Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional México D.F. México

Aim of the Study: The primary aim of the study was to test the effect of 2,4,5-trimethoxy-1-propenylbenzene (alpha asarone), a hypocholes terolaemic drug, on the progression of collagen induced arthritis (CIA) in mice. Olive oil,the vehicle of alpha-asarone, and dexamethasonewere used as control treatments. Set-Up: Four groups of DBA/1 mice were immunised with chicken type II collagen (CII) via the intradermal route and either left untreated or were treated with alpha asarone, olive oil, or dexamethasone. A non-immunised group was an additional control. Follow-Up: The thicknesses of the rear and front footpads were continuously monitored, and the levels of anti-collagen antibodies were measured at the end of the experiment. The animals were then sacrificed, and their rear and front limbs were removed and processed forhistological examination. Results: Alpha asarone had no anti-inflammatory effect on CIA, and in one third of the animals, it showed a proinflammatory effect that was characterised by a marked accumulation of neutrophils. Olive oil did not show any obvious antiinflammatory effect on CIA, but it lowered the level of CII antibodies by 50%, suggesting a potential long-term antiinflammatory effect. As expected, dexamethasone had a clear anti-inflammatory effect on CIA. Con- clusion: Alpha asarone did not show any antiinflammatory effect on CIA in the mice under the above conditions;however, the accumulation of neutrophils in the CIA lesions of mice treated with alpha asarone and the effect of olive oil in downregulating the levels of anti-CII antibodies in CIA are two findings that warrant further investigation.

关键词： Collagen Arthritis Mouse Asarone Olive Oil Dexamethasone

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Dinamic of Bacteria Desnitrificants and Nitrificants in the Rizospheric of Wheat with Slow Release of Fertilizer,Irrigated with Waste or Well Water

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Advances in Microbiology 2013年第4期3卷 343-349页

作者： Sandra Grisell Mora-Ravelo Francisco Gavi Reyes Jesús Pérez Moreno Juan JoséPena Cabriales Leonardo Tijerina ch.vez Made Lourdes de la Isla de Bauer Posgrado en Biología Instituto Tecnológico de Ciudad VictoriaCiudad VictoriaMéxico Programa de Hidrociencias Colegio de PosgraduadosMontecilloMéxico Programa de Edafología Colegio de PosgraduadosMontecilloMéxico Departamento de Biotecnología CINVESTAVIrapuatoMéxico

The study of the paper about the rhizosphere in the transformation of nitrogen compounds can generate knowledge of the microbial and biochemical atmosphere of the rhizosphere of wheat, for the understanding of the dynamics of the N in agricultural zones, with the purpose of optimizing the fertilizer use and increasing the productivity of the cultures. Therefore, the objective of the present work was to know the effect the rhizosphere in the dynamics of the bacterial populations that take part in the cycle of the N in wheat nourished with slow release fertilizer and one commercial, irrigated with waste water or well. Analyses in the soil took place vertisol used in the experiment with the rhizospheric and non rhizospheric fraction. The slow release fertilizer used has a matrix enriched with N and P and is in the process of being patented (it explains in materials and methods). Each fertilizer was evaluated and the combination of the slow release fertilizer with organic fertilizer. The technique of the number most probable was used (MNP) to carry out the quantification of the nitrificants and denitrificants bacteria to the 55, 67 and 97 days after sowing (Dds). The results obtained for the MNP of denitrificants bacteria and Nitrosomonas indicate that the effect average of the types of water, soil and fertilizers, as well as their interaction to each other was not significant (p > 0.05). The effect of the fertilizing type and soil (rhizospheric and non rhizospheric) in the MNP of Nitrobacter was significant (p < 0.05). The tendencies show that the non rhizospheric soil is more favorable for the development of denitrificants bacteria and Nitrobacter, whereas the MNP of Nitrosomonas was greater in rhizospheric soil.

关键词： Nitrificants Vermicompost Nitrites Nitrates Ammonium

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Phytochemical Composition, Anti-Inflammatory and Cytotoxic Activities of chloroform Extract of <i>Senna crotalarioides</i>Kunth

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American Journal of Plant Sciences 2021年第6期12卷 887-900页

作者： Roberto Serrano-Vega Salud Pérez-Gutiérrez Francisco Alarcón-Aguilar Julio Almanza-Pérez Cuauhtémoc Pérez-González Marco Martín González-ch.vez Departamento de Sistemas Biológicos Universidad Autónoma Metropolitana-Xochimilco Mexico City México Departamento de Ciencias de la Salud Universidad Autónoma Metropolitana-Iztapalapa Mexico City México Facultad de Ciencias Químicas Centro de Investigación y Estudios de Posgrado Universidad Autónoma de San Luis Potosí Zona Universitaria San Luis Potosí México

Senna crotalarioides is used in traditional medicine to treat inflammation. The aim of this work was to investigate the anti-inflammatory and cytotoxic activities and the possible mechanism of action of the chloroform extract washed with hexane of S. crotalarioides (CESC). The anti-inflammatory effect was tested on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in mice. The levels of TNF-α, IL-1β, IL-6 and IL-10 were determined in macrophages J774A.1 stimulated by lipopolysaccharide (LPS). The cytotoxic activity was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay against six human cancer cell lines: HeLa (cervical cancer), SKLU-1 and A549 (lung cancer), LNCaP (prostate cancer), SW620 (colon cancer) and MCF7 (breast cancer). The composition of the CESC was determined by GC-MS analysis, and standardized by HPLC-ELSD with ursolic acid as the phytochemical marker. CESC inhibited ear edema 61.45%. In chronic ear edema, CESC diminished the inflammation by 53.77%. CESC decreased TNF-α, IL-1β and IL-6 concentrations, and increased the concentration of IL-10. The extract showed IC50 values on HeLa, SKLU-1, A549, LNCaP, SW620 and MCF7 b

关键词： Senna crotalarioides Anti-Inflammatory Ursolic Acid Composition Cytotoxic

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