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Numerical study of unsteady cavitation on 2D NACA0015 hydrofoil using free/open source software

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Chinese Science Bulletin 2014年第26期59卷 3276-3282页

作者： victor hidalgo Xianwu Luo Bin Ji Alvaro Aguinaga State Key Laboratory of Hydroscience and Engineering Tsinghua University Mechanical Engineering Departments Escuela Politecnica Nacional University

The free/open source software as OpenFOAM,Salome meshing and python language under Debian Linux system are evaluated to model unsteady cavitating turbulent flow around a NACA0015 hydrofoil. Based on the cavitation model proposed by Kunz and large eddy simulation(LES) method, we denote the benefits of free software and open source tools as an alternative to proprietary software of computational fluid mechanics, and provided a modified cavitation model to improve numerical *** simulation results of typical break-off cycle for cavitation shedding are compared to available experimental data, and validated using image processing to find percentage of similarities. The sheet cavity frequency of 7.752 Hz was obtained based on cavitation evolution and pressure fluctuations. The study gives relevant information for CFD software development in the future.

关键词：空化模型开源软件自由软件非定常数值研究水翼 Python语言 Linux系统

Restoration-Focused Germination and Development of Five Central Mexican Oak Species

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Open Journal of Forestry 2014年第3期4卷 171-180页

作者： Alfonso-Corrado Cecilia Campos Jorge Eduardo Mendoza Ana Aguirre-hidalgo victor Valencia-Davalos Susana González-Adame Gabriel Wooden Garvey Fanny Clark-Tapia Ricardo Herbario de la Facultad de Ciencias (FCME) Departamento de Biología Comparada UNAM Ciudad Universitaria México D.F. México Instituto de Ecología UNAM Ciudad Universitaria México D.F. México Instituto de Estudios Ambientales Universidad de la Sierra Juárez Oaxaca México Laboratorio de Bioquímica Molecular-Unidad de Biotecnología y Prototipos (UBIPRO) Fes–IZTACALA Tlalnepantla México Nova Universitas Carretera a Puerto ángel Km. 34.5 Ocotlán de Morelos México

In the genus Quercus, regeneration by seed is reduced or absent in many species. The naturally protected area of the Sierra Fria, in Aguascalientes, Mexico contains forests that are fragmented and have been degraded due to human activities. The oak populations in this region demonstrate a very restricted sexual regeneration, with five of the most abundant species of this genus: Quercuseduardii, Q. grisea, Q. potosina, Q. resinosa and Q. sideroxyla presenting low seedling recruitment. In this study we evaluated seed viability and the effect of seed size on the germination, growth and survival of the trees, with the aim of recommending restoration and conservation program management actions for these oak species. In 2005 and 2006, 5000 acorns of each species were collected and viability, germination and growth experiments were performed in the laboratory and greenhouse. We found high seed viability and significant size effect

关键词： Acorns Oak Regeneration Seed Size Seed Viability

Confirmatory factor analysis of VISA-P scale and measurement invariance across sexes in athletes with patellar tendinopathy

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Journal of Sport and Health Science 2017年第3期6卷 365-371页

作者： Sergio Hernandez-Sanchez Ferran Abat María D.hidalgo Antonio I.Cuesta-Vargas victor Segarra Jose M.Sanchez-Ibanez Antonia Gomez-Conesa Department of Pathology and Surgery Physiotherapy AreaMiguel Hernandez UniversityValencia 03550Spain Sports Orthopaedic Surgeon ReSport ClinicBarcelona 08017Spain Department of Basic Psychology and Methodology University of MurciaMurcia 30100Spain Department of Physiotherapy Faculty of Health SciencesUniversity of MalagaMalaga 29009Spain

Background:The victorian Institute of Sport Assessment–Patella(VISA-P) scale is the most condition-specific patient-reported outcome measure used to assess symptom severity in athletes with patellar *** exploratory factor analyses have been conducted to evaluate the scale's dimensionality,with inconsistent results,and the factor structure of the scale remains *** aims of the present study were to determine the factorial structure of the VISA-P scale using confirmatory factor analysis(CFA) and test measurement invariance across ***:The study included a convenience sample of 249 Spanish athletes with patellar *** was performed to assess factorial *** 1-and 2-factor models were *** invariance across sexes was evaluated via multi-group CFA with several fit indices using EQS 6.1 ***:The internal consistency coefficient was *** CFA models were examined and the 1-factor model in which errors for Items 7 and8 were correlated showed acceptable fit in terms of comparative fit index(CFI) and goodness-of-fit index(GFI) statistics(CFI = 0.93;GFI = 0.94;standardized root mean square residual = 0.06;root mean square error of approximation = 0.10;90% confidence interval:0.08–0.13).This model was invariant across ***:The 1-factor model of the Spanish version of the VISA-P scale(VISA-P-Sp) in which errors for Items 7 and 8 were correlated demonstrated relative fit in *** obtained via VISA-P-Sp can be compared between men and women without sexes *** studies should examine the VISA-P scale and other single-score patient-reported outcome measures concurrently.

关键词： Jumper's knee Measurement invariance Patient-reported outcome measure Structural validity

Validity,reliability,and psychometric properties of a computerized,cognitive assessment test(Cognivue^®)Validity,reliability,and psychometric properties of a computerized,cognitive assessment test(Cognivue^®)

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World Journal of Psychiatry 2020年第1期10卷 1-11页

作者： Diego Cahn-hidalgo Paul W Estes Reina Benabou Internal Medicine of Brighton RochesterNY 14623United States Cognivue Inc. VictorNY 14564United States

BACKGROUND Cognitive issues such as Alzheimer’s disease and other dementias confer a substantial negative *** relating to sensitivity,subjectivity,and inherent bias can limit the usefulness of many traditional methods of assessing cognitive *** To determine cut-off scores for classification of cognitive impairment,and assess Cognivue®safety and efficacy in a large validation *** Adults(age 55-95 years)at risk for age-related cognitive decline or dementia were invited via posters and email to participate in two cohort studies conducted at various outpatient clinics and assisted-and independent-living *** the cut-off score determination study(n=92),optimization analyses by positive percent agreement(PPA)and negative percent agreement(NPA),and by accuracy and error bias were *** the clinical validation study(n=401),regression,rank linear regression,and factor analyses were *** in the clinical validation study also completed other neuropsychological *** For the cut-off score determination study,92 participants completed *** University Mental Status(SLUMS,reference standard)and Cognivue^®*** showed that SLUMS cut-off scores of26(no impairment)corresponded to Cognivue^®scores of 54.5(NPA=0.92;PPA=0.64)and 78.5(NPA=0.5;PPA=0.79),***,conservatively,Cognivue^®scores of 55-64 corresponded to impairment,and 74-79 to no *** the clinical validation study,401 participants completed≥1 testing session,and 358 completed 2 sessions 1-2 wk ***^®classification scores were validated,demonstrating good agreement with SLUMS scores(weightedκ0.57;95%CI:0.50-0.63).Reliability analyses showed similar scores across repeated testing for Cognivue^®(R2=0.81;r=0.90)and SLUMS(R2=0.67;r=0.82).Psychometric validity of Cognivue^®was demonstrated *** neuropsychological *** were most closely correlated with measures of verbal pro

关键词： Cognitive screening test Dementia Memory Motor control Perceptualprocessing Visual salience

Landscape genetics reveals inbreeding and genetic bottlenecks in the extremely rare short-globose cacti Mammillaria pectinifera (Cactaceae) as a result of habitat fragmentation

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Plant Diversity 2017年第1期39卷 13-19页

作者： Reyna Maya-Garcia Santiago Arizaga Pablo Cuevas-Reyes Juan Manuel Penaloza-Ramirez victor Rocha Ramirez Ken Oyama Facultad de Biologia Universidad Michoacana de San Nicolas de Hidalgo Mexico Escuela Nacional-de Estudios Superiores Unidad Morelia UNAM Antigua Carretera a Pdtzcuaro 8701 Colonia Ex-Hacienda de SanJose de la Huerta58190 Morelia Michoacan Mexico

Mammillaria pectinifera is an endemic, short-globose cactus species, included in the IUCN list as a threatened species with only 18 remaining populations in the Tehuacfin-Cuicatlan Valley in central Mexico. We evaluated the population genetic diversity and structure, connectivity, recent bottlenecks and population size, using nuclear microsatellites. M. pectinifera showed high genetic diversity but some evidence of heterozygote deficiency （F15）, recent bottlenecks in some populations and reductions in population size. Also, we found low population genetic differentiation and high values of connectivity for M. pectinifera, as the result of historical events of gene flow through pollen and seed dispersal. M. pectinifera occurs in sites with some degree of disturbance leading to the isolation of its populations and decreasing the levels of gene flow among them. Excessive deforestation also changes the original vegetation damaging the natural habitats. This species will become extinct if it is not properly preserved. Furthermore, this species has some ecological features that make them more vulnerable to disturbance such as a very low growth rates and long life cycles. We suggest in situ conservation to prevent the decrease of population sizes and loss of genetic diversity in the natural protected areas such as the Tehuacan-Cuicatlan Biosphere Reserve. In addition, a long-term ex situ conservation program is need to construct seed banks, and optimize seed germination and plant establishment protocols that restore disturbed habitats. Furthermore, creating a supply of living plants for trade is critical to avoid further extraction of plants from nature.

关键词： MammiUaria pectiniferaNuclear SSRGenetic diversityRecent bottlenecksEffective population size

Effect of Temperature, pH and Water Activity on <i>Penicillium digitatum</i>Growth

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Journal of Applied Mathematics and Physics 2014年第10期2卷 930-937页

作者： María Luisa Carrillo-Inungaray Madeleine hidalgo-Morales Guadalupe del Carmen Rodríguez-Jimenes Miguel ángel García-Alvarado Mario Ramírez-Lepe Abigail Reyes Munguía victor Robles-Olvera Universidad Autónoma de San Luis Potosí Ciudad Valles México Unidad de Investigación y Desarrollo en Alimentos Instituto Tecnológico de Veracruz Veracruz México

Growth curves fitted Penicillium digitatum were used to analyze the effect of temperature, pH and aw on their growth. To asses observance of independent variable effects on all growth parameters (λ, latency time, μ, growth rate and ymax maximal growth) a slow growth strain of P. digitatum was employed. Growth curves were obtained at different conditions of temperature (10?C - 40?C), pH (3.0 - 7.0) and water activity (0.800 - 0.990) and growth parameters were calculated by fitting of logistic model. Polynomial models were made by linear regression and all terms (linear, quadratic and interactive effects) were statistically significant (p < 0.001). All growth parameters, including maximal growth were affected by environmental conditions;pH effect was more important on maximal growth than that on lag time or growth rate. In some aspects results and modeling behavior of P. digitatum, are very similar to modeling of bacterial growth.

关键词： Fungi Growth Model P. Digitatum Slow Growth Food Safety Food Spoilage

Root Secretion of Phytochemicals in Arabidopsis Is Predominantly Not Influenced by Diurnal Rhythms

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Molecular Plant 2010年第3期3卷 491-498页

作者： Dayakar V. Badri victor M. Loyola-Vargas Corey D. Broeckling Jorge M. Vivanco Center for Rhizosphere Biology Colorado State University Fort Collins CO 80523 USA 30 Col. Chuburna de Hidalgo Merida Yucatan Mexico

Root-secreted phytochemicals mediate multiple interactions in the rhizosphere. The root exudation process can be altered by various biotic factors, including pathogenic and non-pathogenic microbes, and abiotic factors like temperature and soil moisture. It has been suggested that root secretion of specific flavonoids is influenced by diurnal rhythms （by light or dark） but a comprehensive analysis of the overall secretion of phytochemicals in response to diurnal rhythms has not been studied. In this study, we analyzed the effect of light/dark cycles on root exudation profiles using Arabidopsis as a model plant. Our results reveal that the root secretion of phytochemicals is partly regulated by the diurnal light cycle and follows two main patterns of secretion：（1） the large majority of phytochemicals in the exudates showed no diurnal pattern in their secretion, and （2） a few compounds showed a diurnal pattern in their secretion： three compounds increased in secretion only under light; two compounds increased in secretion only while it was dark; and two compounds increased in secretion during the transition from dark to light. Root-specific ABC transporters have been implicated in root exudation; an analysis of the gene expression patterns of ABC transporters in the roots of Arabidopsis at specific time points revealed that none of the ABC transporters followed a diurnal expression pattern, suggesting that they are expressed constantly during the day and night. Similarly, we analyzed the expression in roots of genes involved in secondary metabolite biosynthesis and found that some of the genes involved in phenylpropanoid and glucosinolate biosynthesis （i.e. 4-coumarate-CoA ligases （4CL1 and 4CL2）, flavonol synthases （FSl and FS2）, and CYP79B3） followed distinct diurnal expression patterns. Overall, we have discovered that while root exudation of the majority of phytochemicals is constitutive, the secretion of a few compounds follows a diurnal rhythm, which is in accor

关键词： Arabidopsis diurnal rhythm root exudates ABC transporters secondary metabolite biosynthesis.

Molecular isolation and identification of Mycobacterium avium *** in Didelphis virginiana from hidalgo,Mexico

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Asian Pacific Journal of Tropical Medicine 2020年第3期13卷 131-136页

作者： Nallely Rivero-Perez Juan Ocampo-López Benjamín Valladares-Carranza Fabián R.Gómez de Anda Francisco J.Pena Jiménez victor M.Martínez Juárez Armando Peláez Acero Jose I.Olave Leyva Deyanira Ojeda-Ramírez Adrian Zaragoza-Bastida Area Académica de Medicina Veterinaria y Zootecnia Instituto de Ciencias AgropecuariaUniversidad Autónoma del Estado de HidalgoAv.Universidad Km 1Ex-Hda.de AquetzalpaC.P.43600 TulancingoHidalgoMéxico Centro de Investigación y Estudios Avanzados en Salud Animal Facultad de Medicina Veterinaria y ZootecniaUniversidad Autónoma del Estado de MéxicoKm 15.5 Carretera Panamericana Toluca-AtlacomulcoC.P.50200 TolucaEstado de MéxicoMéxico Centro Universitario del Sur/División de Ciencias de la Salud/Departamento de Ciencias Clínicas/Hospital Veterinario CUSUR Universidad de Guadalajara Av.Enrique Arreola Silva No.883colonia centro C.P.49000Ciudad GuzmánJaliscoMéxico

Objective:To isolate and identify the exact species of the genus Mycobacterium from Didelphis(D.)virginiana,and the direct implications of this bacterium to public health and veterinary ***:Thirty-one *** were captured and necropsied in hidalgo,*** samples were collected to culture mycobacteria present and examine individual specimens’*** identification was obtained through the application of amplification and sequencing of 16S rDNA ***:Three strains were isolated and identified as Mycobacterium(M.)avium *** by utilizing *** complexspecific *** lesions were observed in the subpleural zone(granuloma gradeⅡ)and bronchial(granuloma gradeⅠ)of the lungs of *** with positive ***:Three strains of *** ***,from lung tissue samples of *** were *** subspecies of *** has important implications in public health and veterinary medicine.

关键词： Didelphis virginiana Mycobacterium avium complex Mycobacterium avium subsp.hominissuis Public health

Studying Some Brain and Ovarian Morphological Traits in Diaglena spatulata Female Frogs Thriving in Conserved and Perturbed Habitats:A Preliminary Report and Its Implications for Amphibian Survival and Continuity

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Advances in Bioscience and Biotechnology 2014年第9期5卷 740-747页

作者： Esperanza Melendez-Herrera Bryan victor Phillips-Farfan Fany Edith Bucio-Pina Noemi Ramirez-Arres Gabriel Gutierrez-Ospina Ireri Suazo-Ortuno Javier Alvarado-Diaz Alma Lilia Fuentes-Farias Laboratorio de Ecofisiologia Animal Departamento de ZoologiaInstituto de Investigaciones sobre los Recursos NaturalesUniversidad Michoacana de San Nicolas de HidalgoMoreliaMéxico Laboratorio de Nutricion Experimental Instituto Nacional de PediatriaSecretaria de SaludMexico Distrito FederalMexico Laboratorio de Biologia de Sistemas Departamento de Biologia Celular y FisiologiaInstituto de Investigaciones BiomedicasCoordinacion de Psicobiologia y NeurocienciasFacultad de PsicologiaUniversidad Nacional Autonoma de MexicoMexico Distrito FederalMexico Laboratorio de Ecologia Departamento de ZoologiaInstituto de Investigaciones sobre los Recursos NaturalesUniversidad Michoacana de San Nicolas de HidalgoMoreliaMexico Laboratorio de Herpetologia Departamento de ZoologiaInstituto de Investigaciones sobre los Recursos NaturalesUniversidad Michoacana de San Nicolas de HidalgoMoreliaMexico

Amphibians are thought to be highly susceptible to perturbed environments. However, recent studies show that many of them are successful inhabitants of disturbed, fragmented habitats. The source of this resilience is yet unclear, but it may be the byproduct of having a robust phenotype and/or the result of phenotypic plasticity. We then assessed the contribution of each by evaluating cytological features of two brain nuclei that modulate reproductive behavior and of the ovary, using female specimens of the frog Diaglena spatulata prospering in conserved and disturbed areas of a tropical dry forest. Our results in the brain show that the medial amygdala, but not the preoptic area, had a reduced size in frogs collected in disturbed forests compared to specimens collected in conserved forests. Both brain nuclei displayed, however, neurons with a reduced size in frogs captured in disturbed forest patches. In contrast, ovarian cytological features were similar between groups. Our preliminary results lead us to propose that Diaglena spatulata female specimens might combine robust ovary and plastic brain’s phenotypic traits to confront disturbed environments. This, however, is still a working hypothetical framework that needs to be experimentally confirmed.

关键词： Amphibians Reproductive Traits Amygdala Medial Preoptic Area Ovary