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Electron Raman scattering in semiconductor quantum well wire of cylindrical ring geometry

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chinese Physics B 2015年第11期24卷 442-447页

作者： Re.betancourt-Riera Ri.betancourt-Riera J.M.Nieto Jalil R.Riera Instituto Tecnol ógico de Hermosillo.Avenida Tecnol ógico S/N Col.Sahuaro Departamento de Investigaci ón en Física Universidad de Sonora Tecnol ógico de Monterrey-campus Sonora Norte.Bulevar Enrique Mazón López No.965

We study the electron states and the differential cross section for an electron Raman scattering process in a semi- conductor quantum well wire of cylindrical ring geometry. The electron Raman scattering developed here can be used to provide direct information about the electron band structures of these confinement systems. We assume that the system grows in a GaAs/Al0.35Ga0.65As matrix. The system is modeled by considering T = 0 K and also a single parabolic con- duction band, which is split into a sub-band system due to the confinement. The emission spectra are discussed for different scattering configurations, and the selection rules for the processes are also studied. Singularities in the spectra are found and interpreted.

关键词： electron states Raman scattering selection rules quantum well wires

Impact of ZnSO_(4)^(-)and ZnO Nanoparticles on Seed Germination and Seedling Growth of Lettuce

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Phyton-International Journal of Experimental Botany 2023年第6期92卷 1831-1840页

作者： Adalberto Benavides-Mendoza Rebeca betancourt-Galindo Nazario Francisco-Francisco Departamento de Horticultura Universidad Autónoma Agraria Antonio NarroSaltillo25315México Departamento de Materiales Avanzados Centro de Investigación en Química AplicadaSaltillo25294México Departamento de Agricultura Sustentable y Protegida Universidad Tecnológica de TehuacánTehuacán75859México

Micronutrient nanoparticles(NPs)are currently an option for chemical fertilization and biostimulation in crops.However,there is little information on the phytotoxic or biostimulatory effects of NPs at low concentrations of some elements,such as Zn.In this study,the effect of low concentrations of Zn oxide(ZnO)NPs on germination,growth variables,and nutritional attributes of lettuce(Lactuca sativa L.)was evaluated in comparison to Zn sulfate.Romaine lettuce seeds were treated with ZnSO_(4)^(-)×7H_(2)O and ZnO NPs at Zn molar concentrations of 1×10^(−3),5×10^(−3),1×10^(−4),5×10^(−4),1×10^(−5),5×10^(−5),1×10^(−6),and 5×10^(−6).The seeds treated with ZnSO4−at 5×10^(−6)registered the highest radicle length,73%more than the control treatment.The seeds treated with ZnSO4−at 5×10^(−3)registered the lowest values,with 50%less than the control treatment.ZnO NPs at 5×10^(−6)significantly increased content of chlorophyll A and B and total phenolics.These results indicate the possible existence of a mechanism related to the intrinsic nanoparticle properties,especially at low concentrations.

关键词： Micronutrients biostimulation nanotechnology nanofertilizers germination chlorophyll total phenols

Synthesis and characterization of bulk composite Fe-Si-B alloys with small concentration of Nb and Mo

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Acta Metallurgica Sinica(English Letters) 2010年第6期23卷 401-408页

作者： S.Bez I.betancourt I.A.Figueroa Institute for Materials Research National Autonomous University of Mexico (UNAM)

The preparation and some mechanical, thermal and magnetic properties of the as cast bulk composite Fe72B19.2Sin.sM4 （M=Nb, Mo） alloys obtained by suction casting are presented and discussed. The microstructrural results showed the existence of a crystalline a-Fe（Si） phase embedded in a glassy matrix. The values of microhardness （/Iv） and yield strength （ay） for the Nb-containing alloy are exceptionally high, i.e. （12.65~0.3） GPa and （4.22~0.10） GPa, respectively. The saturation polarization values are found to be as high as 1.24 T for both composite ~11oys. It is thought that the interplay between the secondary crystalline phases and amorphous matrix could be responsible for the mechanical and magnetic behaviour of these alloys.

关键词： Bulk composite alloys Magnetic properties Mechanical proper- ties Thermal stability and suction casting

通过抑制富勒烯材料的自聚集制备高效稳定的反式钙钛矿太阳电池

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Science Bulletin 2021年第4期66卷 339-346,M0004页

作者：田成波 German betancourt-Solis 南子昂刘凯凯林克斌卢建勋谢立强 Luis Echegoyen 魏展画 Institute of Luminescent Materials and Information Displays College of Materials Science and EngineeringHuaqiao UniversityXiamen 361021China Department of chemistry University of Texas at El PasoEl PasoTX 79968USA ichEM(collaborative Innovation center of chemistry for Energy Materials) Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

富勒烯作为电子传输层材料对钙钛矿太阳电池器件的缺陷钝化及性能提高都有重要的影响.然而,富勒烯分子的笼状结构易于自聚集,形成团聚物,这种现象在持续光热条件下变得更加严重,会影响相应太阳电池的稳定性.鉴于此,本文通过在富勒烯碳... 详细信息

富勒烯作为电子传输层材料对钙钛矿太阳电池器件的缺陷钝化及性能提高都有重要的影响.然而,富勒烯分子的笼状结构易于自聚集,形成团聚物,这种现象在持续光热条件下变得更加严重,会影响相应太阳电池的稳定性.鉴于此,本文通过在富勒烯碳笼上目的性地引入芳香性的修饰基团,得到富勒烯衍生物PcBB分子.单晶结构表明,芳香性基团的引入有效地增加了PcBB分子间的相互作用.分子间相互作用的增强有效促进了电子在富勒烯碳笼间的跃迁,进而增加了PcBB薄膜的电子迁移速率,提升了相应钙钛矿太阳电池的效率.尤为重要的是,PcBB分子间的强相互作用有效地抑制了富勒烯分子的自聚集,从而提升了其薄膜的稳定性,相应的钙钛矿太阳能电池器件在持续光照条件下显示出了良好的工况稳定性.

关键词：钙钛矿太阳电池钙钛矿太阳能电池分子间相互作用富勒烯衍生物芳香性光热条件自聚集笼状结构

Polyorchidism： the case in a young male and review of the literature

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Asian Journal of Andrology 2015年第3期17卷 511-512页

作者： Ana Avargues Ramon Rogel Enrique Broseta Saturnino Lujan Jesus A betancourt Gonzalo Morales Francisco Boronat Department of Urology University and Polytechnic Hospital La Fe Valencia 46026 Spain

Dear Editor, Polyorchidism refers to the presence of more than two testicles. Blasius described it for the first time in 1670 as an incidental finding in an autopsy, while Lane was the one who performed the first histological description of a supernumerary testis in 1895.1,2 Before imaging diagnosis techniques, this condition could only be verified under surgical exploration. Nowadays, current imaging techniques have increased the number of diagnosis of this anatomical variation. On the other hand, there is still a certain group of physicians who use histological analysis as the unioue way to diagnosis.

关键词： MANAGEMENT

Pronuclear formation by IcSI using chemically activated ovine oocytes and zona pellucida bound sperm

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Journal of Animal Science and Biotechnology 2017年第2期8卷 370-377页

作者： J.E.Hernández-Pichardo Y.Ducolomb S.Romo M.E.Kjelland R.Fierro F.casillas M.betancourt División de ciencias Biológicas y de la Salud Departamento de Producción Agrícola y AnimalUniversidad Autónoma Metropolitana-XochimilcoCiudad de MexicoMexico Division de ciencias Biologicas y de la Salud Departamento de Ciencias de la SaludUniversidad Autónoma Metropolitana-IztapalapaSan Rafael Atlixco 186CP 09340 Ciudad de MexicoMexico Departamento de ciencias Pecuarias Facultad de EstudiosSuperiores CuautitlanUNAMCiudad de MexicoEstado de MexicoMexico conservation Genetics&BiotechLLCValley CityNDUSA Division de ciencias Biologicas y de la Salud Departamento de Biologia de la ReproduccionUniversidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico Doctorado en Biologia Experimental Universidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico

Background： In order to improve IcSI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using IcSI with chemically activated ovine oocytes and sperm selected by swim up（SU） or swim up ＋ zona pellucida（SU ＋ ZP） binding.Results： Experiment 1, 4–20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation（precense of one PN）. Treatments showed similar results（54, 47, 42 %, respectively） but statistically differents（P 0.05）.conclusions： chemical activation induces higher ovine oocyte activation than mechanical activation. Ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. Sperm selection with SU ＋ ZP increased AR/A and AR/D rates in comparison with SU in fresh and frozen-thawed sperm. According to this, in terms of fertilization rates, chemical activation after IcSI increased oocyte PN formation compared to mechanical activation. Also, fresh sperm treated with SU and SU ＋ ZP were significantly different than frozen-thawed sperm,but between sperm treatments no significant differences were obtained.

关键词： Ethanol IcSI Oocyte activation Ovine Pronucleus Zona pellucida

Microbiota and Mycotoxins in Trilinear Hybrid Maize Produced in Natural Environments at central Region in Mexico

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Advances in Microbiology 2016年第9期6卷 671-676页

作者： Peña betancourt Silvia Denise Toxicology Laboratory Department of Agricultural and Animal Production Autonomous Metropolitan University Unit-Xochimilco Mexico City Mexico

Mycotoxigenic fungi and mycotoxins in 3 inbred lines (hybrids resistant to corn ear rot) were identified in twenty samples. The maize (Zea mays) accessions were collected in five plots of two municipalities in High Valley, state of Hidalgo. The fungal population was determined with a microbiological dilution method used two culture media (PDA and ELA), for the detection of mycotoxins with thin layer chromatography with visual inspection in UV light and a direct competitive enzyme-linked immunosorbent (ELISA). The results showed high moisture content in all hybrids evaluated on an average of 38.3% and a 1.8 × 103 UFc/g fungus, values within the permitted limits by the Mexican legislation;however the most prevalent fungi were Fusarium sp. (76%), Alternaria sp. (14%), Penicillium sp. (4%) and Aspergillus sp. (5%), and the species Aspergillus nidulas, Aspergillus flavus, Fusarium verticillioides, Fusarium poae, and Penicillium ochraceum. The aflatoxin concentration was observed in a range from 2 to 13 ng/g and 370 to 660 ng/g to fumonisins. It is concluded that trilinear corn hybrids have a variety of pathogenic potential fungi. The two genetic hybrids showed levels of aflatoxins and fumonisin safe for human consumption, contrary to one hybrid, with a content not suitable for human consumption. A better understanding of genetic hybrids corn will improve predictive mycotoxin contamination.

关键词： Zea mays L. Mycotoxins Fungi corn Hybrid

Propolis in Dogs: clinical Experiences and Perspectives (A Brief Review)

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Open Journal of Veterinary Medicine 2015年第1期5卷 11-17页

作者： Nelly Tovar betancourt Lucila García-contreras Tonatiuh Alejandro cruz Sánchez Facultad de Estudios Superiores cuautitlán Universidad Nacional Autónoma de México Cuautitlán Izcalli México Department of Pharmaceutical Sciences The University of Oklahoma Health Sciences Center Oklahoma City USA

In light of the scarcity of novel therapeutic agents that are effective, the pharmaceutical industry has found a newer source of therapeutic compounds in natural products and herbal medicine to address the current health problems in humans and animals. What is particularly promising about these agents is that they produce fewer side effects and are more cost effective than synthetic compounds. This means greater availability of these treatments particularly for less developed countries who can’t afford expensive treatments. The reduced side effects also mean greater patient tolerance and increased compliance thereby yielding maximal therapeutic effect without negatively impacting on quality of life. Among the natural products more frequently employed nowadays is propolis, a resin that is routinely collected by bees (Apis mellifera). Propolis contains flavonoids, caffeic acid esters and diterpenic acids, which provide the bactericidal, antiviral and antifungal properties to this product. The use of propolis to address a variety of conditions in small animal species is beginning to play an important role in the currently available treatments. Its use appears to be an effective treatment with no side effects at low cost. This paper reviews the different applications of this compound to treat diseases in dogs.

关键词： Dog Propolis Uses Treatments Perspectives

The animal cachexia score(AcAScO)

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Animal Models and Experimental Medicine 2019年第3期2卷 201-209页

作者： Angelica betancourt Sílvia Busquets Marta Ponce Míriam Toledo Joan Guàrdia‐Olmos Maribel Peró‐cebollero Francisco J.López‐Soriano Josep M.Argilés cancer Research Group Departament de Bioquímica i Biomedicina MolecularFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain Institut de Biomedicina de la Universitat de Barcelona BarcelonaSpain Advanced Statistical Data Analysis Applied to Psychology Departament de Metodologia de les Ciències del ComportamentFacultat de PsicologiaUniversitat de BarcelonaBarcelonaSpain Institut de recerca en cervell Cogniciói Conducta(IR3C)BarcelonaSpain

Background:None of the published studies involving cancer cachexia experimental models have included a measure of the severity of the syndrome like the scoring system previously developed for human subjects.The aim of the present investigation was to define and validate a cachexia score usable in both rat and mouse tumor models.Methods:In order to achieve this goal,we included in the study one rat model(Yoshida AH‐130ascites hepatoma)and two mouse models(Lewis lung carcinoma and colon26 carcinoma).The Animal cachexia score(AcAScO)includes five components:(a)body and muscle weight loss,(b)inflammation and metabolic disturbances,(c)physical performance,(d)anorexia,and(e)quality of life measured using discomfort symptoms and behavioral tests.Results:Using the AcAScO values,three cut‐off values were estimated by applying hierarchical cluster analysis.Four groups were originally described,one exactly below the observed mean,a second exactly over the mean,and two other groups adjusted to every cue(inferior and superior).The three cut‐off values were estimated through maximization of the classification function.This was accomplished by using a similarity matrix based on the metric properties of the variables and assuming multinormal distribution.The results show that the four groups were:no cachexia,mild cachexia,moderate cachexia and advanced cachexia.conclusions:The results obtained allow us to conclude that the score could be very useful as an endpoint in pre‐clinical studies involving therapeutic strategies for cancer cachexia.The potential usefulness of AcAScO relates to the primary endpoint in pre‐clinical cancer cachexia drug evaluations.

关键词： anorexia cachexia classification physical performance quality of life score wasting weight loss