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Journal of Mountain Science 2023年第1期20卷 129-140页

作者： CASTRO-TORREBLANCA Marisol espinosa david BUENO-HERNANDEZ Alfredo LUNA-VEGA Isolda Biological Sciences Graduate Program Coordination of Graduate StudiesNational Autonomous University of MexicoUniversity CityCoyoacán04510Mexico CityMexico Comparative Biology and Biodiversity Research Unit Facultad de Estudios Superiores ZaragozaNational Autonomous University of MexicoAv.Batalla del 5 de mayo s/nCol.Ejército de Oriente09230Mexico CityMexico Laboratory of Biogeography and Systematics Department of Evolutionary BiologyFaculty of SciencesNational Autonomous University of MexicoUniversity CityCoyoacán04510Mexico CityMexico

The historical relationships of nine areas of endemism of the tropical montane cloud forests(TMCFs)were analysed based on a temporal cladistic biogeographical *** cladistic biogeographical analyses were conducted based on 29cladograms of terrestrial taxa by partitioning them into three time-slices,namely,Miocene,Pliocene,and *** results showed different area relationships over *** the Miocene and Pliocene time slices,the Isthmus of Tehuantepec acted as a geographic barrier that fragmented the TMCFs into two portions:west of the Isthmus and east of the *** the case of the Pleistocene,the TMCFs were broken into two portions,one related to the Neotropical region and the other to the Nearctic ***,the analyses allowed us to detect the influences of different geological and paleoclimatological events on the distribution of the TMCFs over ***,the TMCFs current distribution might have been driven by geological events during the Miocene-Pliocene,whereas climatic fluctuations have the highest impact during the Pleistocene.

关键词： Dispersal Evolutionary biogeography Paralogy free subtree analysis Vicariance

Diversity, Endemism and Conservation of Ferns(Polypodiales) in the Mexican Mountain Component

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Journal of Mountain Science 2015年第4期12卷 891-904页

作者： SANGINéS-FRANCO Celia LUNA-VEGA Isolda CONTRERAS-MEDINA Raúl espinosa david TEJERO-DíEZ José Daniel RIVAS Gerardo Laboratorio de Biogeografía y Sistemática Departamento de Biología Evolutiva Facultad de Ciencias Universidad Nacional Autónoma de México (UNAM) Escuela de Ciencias Universidad Autónoma "Benito Juárez" de Oaxaca (UABJO) Av.Universidad s/n Ex Hacienda de Cinco Se?ores Oaxaca de Juárez CP 68120 Oaxaca México Facultad de Estudios Superiores Zaragoza Unidad Multidisciplinaria de Investigación Experimental ZaragozaUniversidad Nacional Autónoma de México (UNAM) Carrera de Biología Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de México MéxicoAvenida de los Barrios Número 1 Colonia Los Reyes Iztacala Tlalnepantla CP 54090 Estado de México México Laboratorio de Biogeografía Acuática Departamento de Biología Comparada Facultad de Ciencias Universidad Nacional Autónoma de México (UNAM)

We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices and richness and beta diversity *** data were obtained from several herbaria and specialized *** grid-cells appear to be important for fern species richness, as they contain 35 to 49 *** gridcells are located in the Sierra Madre Oriental(SMO),Trans-Mexican Volcanic Belt(TMVB) and the Sierra Madre del Sur(SMS).Mean richness by latitudinal belts of one degree showed that the belts with highest values are related to the TMVB and SMS.A total of 13grid-cells were recognized as important from theperspective of endemism; most of them are located also in the SMO, TMVB and *** richest gridcells coincided with one of the main centres of endemism for ferns obtained in this study, located in the convergence of the southern part of the SMO, the eastern portion of the TMVB and the northern part of the SMS, reflecting the high humidity existing on the mountain slopes facing the Gulf of *** important grid-cells recognized from richness and endemism analyses coincide with Mexican Natural Protected *** beta diversity analysis showed a low degree of similarity among grid-cells, implying a high species replacement, as the result of environmental heterogeneity occurring in the Mexican mountain *** the other hand, the spatial analysis suggested a pattern of phytogeographical regionalization comprising twomain areas: the Mexican Transition Zone and the Mexican Central *** play an important role in the Mexican biodiversity and contributing to the beta diversity of Mexico.

关键词： Biogeography Distributional patterns Leptosporangiate ferns Mexico

Suppression Effects on Pineapple Soil-Borne Pathogens by Crotalaria juncea,Dolomitic Lime and Plastic Mulch Cover on MD-2 Hybrid Cultivar

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Phyton-International Journal of Experimental Botany 2021年第4期90卷 1205-1216页

作者： Luis Alfonso Aguilar Pérez Daniel NietoÁngel Moisés Roberto Vallejo Pérez Daniel Leobardo Ochoa Martínez david espinosa Victoria Andrés Rebolledo Martinez Abel Rebouças São José Fitopatología Colegio de PostgraduadosMontecillo-Texcoco56230México CONACyT-Universidad Autónoma de San Luis Potosí CIACYTSan Luis Potosí78000México Edafología Colegio de PostgraduadosMontecillo-Texcoco56230México Instituto Nacional de Investigaciones Forestales Agrícolas y PecuariasVeracruz94270México Rebouças São José A.UESB/DFZVitória da Conquista95Brasil

The development and implementation of sustainable and environmentally friendly agricultural practices are indispensable as alternatives to pesticide use and to keep populations of soil-borne plant pathogens at levels that do not affect crop *** present research evaluates the incidence of soil-borne phytopathogens on the pineapple variety MD-2,which was subjected to different treatments:Incorporation of Crotalaria juncea into the soil(organic amendment),application of dolomitic lime to soil(inorganic amendment),and the use of plastic mulch covering the *** the crop cycle(15 months),the following variables were evaluated:plant height(cm),fruit weight(kg·plant^(−1)),crop yield(ton·ha^(−1)),the bud root disease incidence caused by Phytophthora nicotianae,number of soil phytoparasitic nematodes and colony-forming-units(CFUs)of soil fungi and *** results indicate that Crotalaria juncea treatment reduced the pathogen population(nematode and oomycetes)at levels that did not affect crop development,so that yield increased(18–20%).The incorporation of *** into the soil as an organic amendment favors the populations of fungi disease suppressors(Trichoderma-Aspergillus).The phytoparasitic nematodes(Meloidogyne sp.,Pratylenchus sp.,and Mesocriconema sp.)and oomycetes(Phytophthora spp.,and Pythium spp.)showed a reduction of their population levels by effects of organic amendment(***).The plastic mulch was also effective,probably due to the maintenance of optimal condition to crop growth and weed ***,the dolomitic lime application had the poorest effect under the conditions of the study area on the variables *** described observations are characteristics of a system-based approach for the potential management of soil-borne pathogens of pineapple MD-2 in Veracruz,México.

关键词： Suppressive soil integrated pest management Phytophthora nicotiannae Phytoparasitic nematodes

Forecast of the Luminescent Phenomena of Silicon Rich Oxide Films off Stoichiometry by Means of the Global Reaction Model

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Journal of Modern Physics 2015年第11期6卷 1679-1694页

作者： Néstor david espinosa-Torres José álvaro david Hernández de la Luz José Francisco Javier Flores-Gracia José Alberto Luna-López Javier Martínez-Juárez Gregorio Flores-Carrasco IC-CIDS Benemérita Universidad Autónoma de Puebla Puebla México Ex Graduate Research Trainee at Plasma Processing Laboratory Chemical Engineering Department McGill University Montreal Canada Department of Materials Science and Engineering and Chemical Engineering University Carlos III of Madrid and IAAB Madrid Spain

The Global Reaction Model describes a set of chemical reactions that can potentially occur during the process of obtaining silicon rich oxide (SRO) films, regardless of the technique used to grow such films which are an outside stoichiometry material. Particularly, chemical reactions that occur during the process of growing of SRO films by LPCVD technique are highlighted in this model. We suggest and evaluate either some types of molecules or resulting nanostructures and we predict theoretically, by applying the density functional theory, the contribution that they may have to the phenomenon of luminescence which is measured in SRO films. Also, we have calculated the opto-electronic properties of SRO films. The suggested model provides enough information required to identify the molecular structures resulting from the presence of defects in SRO films and also those corresponding to charged structures. It is also possible to detect the molecular structures which are modified due to the effect of heat treatment, and identify the presence of different oxidation states inclusive the formation of siloxanes.

关键词： Global Reactions Model Silicon Rich-Oxide Defects LPCVD Luminescence

<i>Ab Initio</i>Molecular 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

In Situ Tests of Multiwalled Carbon Nanotubes with Strength Close to Theoretical Predictions

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Chinese Physics Letters 2009年第1期26卷 194-197页

作者：彭倍 Horacio D. espinosa Center for Micro and Nano Electromechanical Systems University of Electronic Science and Technology of China Chengdu 610054 Micro and Nano Mechanics Laboratory Northwestern University Illinois 60208 USA

Using MEMS technology and transmission electron microscopy we show experimentally multiwalled carbon nanotubes with a mean fracture strength of larger than 100 GPa, which exceeds the earlier observations by a factor of approximately 3. These results are in excellent agreement with quantum-mechanical estimations. This performance is made possible by omitting chemical treatments from the sample preparation process, thus avoiding the formation of defects. High-resolution imaging is used to directly determine the number of fractured shells and the ehirality of the outer shell. Electron irradiation at 200keV for 10, 100 and 1800s lead to improvements of the maximum sustainable loads by factors of 2.4, 7.9 and 11.6 compared with non-irradiated samples of similar diameter. This effect is attributed to crosslinking between the shells. This procedure is a cost effective way of customizing the properties of multiwall nanotubes for many applications of interest ranging from nanocomposites to nanodevices.

关键词： field emission molybdenum dioxide enhancement factor

Soluble interleukin 23 receptor gene therapy with adeno-associated vectors for the treatment of multiple sclerosis

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Neural Regeneration Research 2017年第10期12卷 1605-1606页

作者： ángel Edo Juan Francisco espinosa-Parrilla Gene Therapy for Central Nervous System Group Vall d'Hebron Institut de Recerca Hospital Universitari Vall d'HebronBarcelonaSpain

Gene therapy as strategy against autoimmune diseases： In the last century, human societies have witnessed remarkable improvements in wellness and life expectancy, thanks to the consolidation of mod- ern science and medicine. But, while some infectious and other dis- eases, have been almost fully controlled, pathologies associated with intrinsic factors and longevity have increased in incidence.

关键词：基因治疗多发性硬化白细胞介素腺相关病毒自身免疫性疾病可溶性受体人类社会

Evidences of hydroxytyrosol as an anti-inflammatory agent in Parkinson’s disease:insights into the mechanisms of action

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Neural Regeneration Research 2021年第5期16卷 992-993页

作者： Ruth Hornedo-Ortega Ana María espinosa-Oliva Axe Molécules d’Intérêt Biologique(MIB) Unitéde Recherche OenologieEA4577USC 1366 INRAISVVUniversitéde BordeauxBordeauxFrance Departamento de Bioquímica y Biología Molecular Facultad de FarmaciaUniversidad de Sevillaand Instituto de Biomedicina de Sevilla(IBiS)Hospital Universitario Virgen del Rocío/CSICSevilleSpain

Neuroinflammation in neurodegenerative diseases:Inflammatory processes play a critical role in neurodegenerative diseases,such as Parkinson’s disease(PD).Thus,neuroinflammation is involved in the progression and development of these diseases,becoming an important pathological *** cells,the“macrophages”from central nervous system,are the initiating cells of the innate immune response against different stimuli in the brain.

关键词： inflammation diseases insight

Increased locomotor activity in estrogen-treated ovariectomized rats is associated with nucleus accumbens dopamine and is not reduced by dietary sodium deprivation

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Integrative Zoology 2018年第6期13卷 783-794页

作者： Enith espinosa Kathleen S.CURTIS Oklahoma State University-Center for Health Sciences TulsaOklahomaUSA

Estrogens are well known to increase locomotor activity in laboratory rodents;however,the underlying mechanism remains *** used voluntary wheel running by female rats as an index of locomotor behavior to investigate this *** first determined whether the estrogen-induced increase in locomotion was susceptible to inhibition by a physiological challenge,and next whether it was associated with dopaminergic activation in the central reward area,nucleus *** rats were given estradiol or the oil vehicle and housed in cages with or without running *** rats were given regular rodent chow for 1 week,a sodium-deficient diet for the next week,and then were returned to a regular diet for another *** the end of the last week,all rats were killed,brains were extracted and dopamine levels in the nucleus accumbens were *** expected,estradiol treatment increased distance ***,dietary sodium deprivation further increased running,but this appeared to be related to experience with wheel running,rather than to sodium deprivation,per *** was greater in the nucleus accumbens of estradiol-treated rats that ran compared to all other ***,the estrogen-induced increase in locomotion is a robust phenomenon that is not inhibited by a body sodium challenge and is associated with elevated levels of dopamine in reward *** findings raise the possibility that the estrogen-induced increase in locomotor activity,which occurs during a hormonal milieu conducive to reproduction,may reflect mate-seeking behavior and,thereby,maximize reproductive success.

关键词： locomotor activity reproductive hormones reward pathways

Digestibility and metabolism of copper in diets for pigs and influence of dietary copper on growth performance,intestinal health,and overall immune status:a review

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Journal of Animal Science and Biotechnology 2021年第2期12卷 426-437页

作者： Charmaine D.espinosa Hans H.Stein Department of Animal Sciences University of IllinoisUrbana 61801USA Division of Nutritional Sciences University of IllinoisUrbana 61801USA

The current contribution reviews absorption and metabolism of copper(Cu),Cu deficiency,Cu toxicity,Cu bioavailability,and effects of pharmacological levels of Cu on growth performance and intestinal health of *** is a micro mineral involved in metabolic reactions including cellular respiration,tissue pigmentation,hemoglobin formation,and connective tissue *** is mostly absorbed in the upper gastrointestinal tract,particularly in the duodenum,but some Cu is absorbed in the *** way to evaluate the efficacy of sources of Cu is to measure relative bioavailability where responses include tissue concentrations of Cu,concentrations of metalloproteins,and enzymatic activity of animals fed test diets containing graded levels of *** requirement for Cu by pigs is 5 to 10 mg/kg diet,however,Cu can be included at growth-promoting levels(i.e.,75 to 250 mg/kg diet)in diets for weanling and growing pigs to reduce post-weaning diarrhea and improve growth *** consistently observed improvement in growth performance upon Cu supplementation is likely a result of increases in lipase activity,growth hormone secretion,and expression of genes involved in postabsorptive metabolism of *** growth-promoting effects of dietary Cu have also been attributed to its bacteriostatic and bactericidal properties because Cu may change bacterial populations in the intestine,and thereby reduce inflammation caused by ***,further research is needed to determine potential interactions between Cu and non-nutritive feed additives(e.g.,enzymes,probiotics,phytobiotics),and the optimum quantity of Cu as well as the optimum duration of feeding supplemental Cu in diets for pigs should be further *** gaps needs to be addressed to maximize inclusion of Cu in diets to improve growth performance while minimizing diseases and mortality.

关键词： Copper Copper nutrition Intestinal health Metabolism Pharmacological concentrations Pigs