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Ocurrence of Entomopathogenic Fungus from Flea Ctenocephalides canis(Siphonaptera:Pulicidae)

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Open Journal of Veterinary Medicine 2014年第12期4卷 281-285页

作者： Jonathan E.ortega-Palomares hector G.Nunez-Palenius Ana M.Cruz-Avalos Aaron A.Hernandez-Rangel Roberto Lezama-Gutierrez Cesar A.Angel-Sahagun Programa Educativo de Medicina Veterinaria y Zootecnia Division Ciencias de la VidaUniversidad de GuanajuatoCampus Irapuato-SalamancaIrapuatoMexico Departamento de Agronomía Division Ciencias de la VidaUniversidad de GuanajuatoCampus Irapuato-SalamancaIrapuatoMexico Instituto Tecnologico Superior de Irapuato AbasoloMexico Posgrado en Biosciencias Division Ciencias de la VidaUniversidad de GuanajuatoCampus Irapuato-SalamancaIrapuatoMexico Facultad de Ciencias Biologicas y Agropecuarias Universidad de ColimaColimaMexico

The objective of this study was to isolate entomopathogenic fungus from fleas (Ctenocephalides canis Curtis) collected from Cannis familiaris specimens. From 60 collected fleas, two dead insects presented white mycelia growth on the body surface, changing to a creamy color as time passed;the insects presented a mummified aspect, typical characteristic caused by entomopathogenic fungus. This fungus was identified as Beauveria bassiana (Balsamo-Crivelli) Vuillemin by their mycelia characteristics, macro- and micro-morphology. Up to our knowledge, this is the first report of entomopathogenic fungus isolated from adult C. canis fleas.

关键词： Ectoparasite Biological Control Dog Beauveria bassiana

Crop Evapotranspiration Estimation through the,Use of Satellite Images

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Journal of Earth Science and Engineering 2013年第10期3卷 663-671页

作者： Enrique Palacios-Velez hector Flores-Magdaleno Water Sciences Department Postgraduate College Texcoco 56230 Mdxico

An efficient water use requires accurate estimations of crop ET （evapotranspiration）. However, an accurate ET estimation is really difficult to achieve when big regions such as irrigation districts or complete watersheds are involved. Satellite images are an alternative that can be used to estimate accurate crop ET for big regions. In the present study, two known methods were used to estimate crop ET, the METRIC model which was developed by the University of Idaho and a Kc-NDVI relationship. In the METRIC model, ET is estimated as a residual of the energy balance equation. The second method uses reference ET, and estimates a crop coefficient （K,.） as a linear function of the NDVI vegetation index. ET was estimated in a section of the Rio Mayo Irrigation District located in Sonora, Mexico using Landsat 7 satellite images. Crop ET of the main crops was estimated. Results show some differences between both methods. An average ET depth of 460 mm for the wheat average growing season was found when using METRIC, while an average ET depth of 421 mm was found when using the Kc-NDVI relationship. A water use total efficiency of 62% and 63% was found for METRIC and the Kc-NDVI relationship, respectively.

关键词： Crop evapotranspiration crop coefficient METRIC NDVI.

Chiral Seismic Attenuation with Acoustic Metamaterials

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Journal of Electromagnetic Analysis and Applications 2013年第1期5卷 10-15页

作者： hector Torres-Silva Diego Torres Cabezas 不详

We study the analogy between the linear elasticity theory equations and classical Maxwell equation with chiral effects and we propose a new method of an earthquake-resistant design to support conventional aseismic designs using acoustic metamaterials. We suggest a simple and practical method to reduce the amplitude of a seismic wave exponentially. Our device is like an attenuator of a chiral seismic wave. Constructing a cylindrical shell-type waveguide that creates a stop-band for the chiral seismic wave, we can convert the wave into an evanescent wave for some frequency range without touching the building we want to protect.

关键词： Chiral Metamaterial Seismic Wave Acoustic Properties

Challenges in the ambient Raman spectroscopy characterization of methylammonium lead triiodide perovskite thin films

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Frontiers of Optoelectronics 2016年第1期9卷 81-86页

作者： Yuanyuan ZHOU hector F. GARCES Nitin P. PADTURE School of Engineering Brown University Providence RI 02912 USA

The importance triiodide （CH3NH3PbI3 or of methylammonium lead MAPbI3） organic-inorganic hybrid perovskites has shot up dramatically since their use in highly efficient thin-film perovskite solar cells （PSCs）. However, the basic structural characterization of these fascinating materials remains sparse. In particular, Raman spectroscopy, which is a powerful vibrational spectroscopy characterization tool and complements other characterization methods, of MAPbI3 under ambient conditions is plagued with difficulties. Here, a systematic ambient Raman spectroscopy characterization study of MAPbI3 thin films is conducted under different conditions （excitation laser wavelength, integration time, filter characteristic）. The results from this study help elucidate the possible sources of artifacts in the Raman spectra, and raise the awareness of the challenges in the ambient Raman spectroscopy of MAPbI3 perovskites. Approaches to overcome these challenges are suggested.

关键词： perovskite solar cells Raman spectroscopy,laser-degradation

Agolin Ruminant^®, an Essential Oil Blend, Increases Energy-Corrected Milk and Feed Efficiency in a High Component Dairy Herd

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Open Journal of Animal Sciences 2023年第3期13卷 272-282页

作者： Jorge Noricumbo-Saenz Peter Williams hector Garcia Feedworks USA Ltd. Cincinnati OH USA Moxee Dairy Moxee WA USA

Agolin® Ruminant (Agolin) is a blend of essential oils developed to improve feed efficiency while at the same time reducing rumen enteric methane production. Studies have shown that the product improves lactational performance, but the range of results has been varied. This experiment evaluated the effects of the feed additive Agolinon milk production in a high-component (fat and protein) dairy herd when provided for an extended time. The experiment was conducted at a large commercial dairy in the Pacific Northwest, USA. Eight pens of cows (350 to 500 cows/pen) were blocked by production, and pens within blocks were randomly assigned to treatment. All pens received a common total mixed ration. Treatment consisted of providing 1 g/cow/day of Agolin to the test group. A 4-week adaptation period was followed by an 11-week study period. Milk production and milk composition were determined by cow by averaging daily performance for the one-week period before the start of the trial (covariate period) and the last week of each of the two test periods. Feed intakes were determined by pen at the same time. Milk yield was 1.11 kg/cow/day greater (P < 0.001) at the midpoint and 1.48 kg/cow/day greater (P < 0.001) at the end of the test period for cows receiving the feed additive. Similarly, protein yields were 0.03 (P < 0.001) and 0.07 kg/cow/day greater (P < 0.001) at the midpoint and end of the feeding period. Milk fat yield was not different (P = 0.854) between treatment groups at the midpoint of the trial but increased with treatment (P = 0.002) by the end of the trial. Energy-corrected milk/feed ratio, based on pen parameters, was significantly altered by treatment at the final test period (1.48 vs. 1.64 kg/kg for control and test treatments, respectively).

关键词： Greenhouse Gas Mitigation Methane Feed Efficiency Lactating Dairy Cows Agolin

Impact of the adherence to medical treatment on the main urinary metabolic disorders in patients with kidney stones

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Asian Journal of Urology 2021年第3期8卷 275-279页

作者： Braulio Omar Manzo Jose David Cabrera Esteban Emiliani hector Manuel Sanchez Brian Howard Eisner Jose Ernesto Torres Urology Department Hospital Regional de Alta Especialidad del BajioBlvd.Milenio#130Col.San Carlos la RonchaLeonGuanajuatoMexico Urology Department Fundacion PuigvertUniversidad Autonoma de BarcelonaBarcelonaSpain Urology Department Massachusetts General HospitalHarvard Medical SchoolBostonUSA

Objective:To assess the effect of the adherence to medical treatment on urinary parameters in the 24-h metabolic study of patients with kidney ***:A retrospective,longitudinal,descriptive,and observational study was carried out by reviewing the hospital electronic medical record from 2014 to *** adherence to drug treatment was measured 6 months after its initiation,and the numerical values of the metabolic studies were *** tests were performed to compare the difference before and after ***:Ninety patients were evaluated,with 73.3% of *** 180-day overall adherence rate was 61.2% in patients treated with a single drug and 85.4% in patients treated with multiple *** is a statistically significant increase in citrate levels in patients with good adherence in comparison with non-adherent patients(p=0.031 vs.p=0.528).Conclusions:Medical treatment and dietary measures in patients with kidney stones have an initial impact at 6 months on the values of the main urinary metabolic alterations that predispose to calculi formation;the most significant is seen in those patients with adherence to medical treatment for hypocitraturia.

关键词： Kidney stones Renal stones Metabolic disorders Medical treatment Citrate Oxalate Lithiasis

Chiral Current in a Graphene Battery

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Journal of Electromagnetic Analysis and Applications 2012年第10期4卷 426-431页

作者： hector Torres-Silva Diego Torres Cabezas Escuela de Ingeniería Eléctrica Electrónica Universidad de Tarapacá Arica Chile Modernización y Gobierno Electrónico Ministerio Secretaría General de la Presidencia Santiago Chile.

We review the formulation of graphene’s massless Dirac equation, under the chiral electromagnetism approach, hopefully demystifying the material’s unusual chiral, relativistic, effective theory. In Dirac’s theory, many authors replace the speed of light by the Fermi velocity, in this paper we deduce that in graphene the Fermi velocity is obtained from the connection between the electromagnetic chirality and the fine structure constant when the electric wave E is quasi parallel to the magnetic wave H. With this approach we can consider the properties of electric circuits involving graphene or Weyl semimetals. The existence of the induced chiral magnetic current in a graphene subjected to magnetic field causes an interesting and unusual behavior of such circuits. We discuss an explicit example of a circuit involving the current generation in a “chiral battery”. The special properties of this circuit may be utilized for creating “chiral electronic” devices.

关键词： Chiral Dirac Battery Grapheme Weyl Semimetal

Relations between stellar mass and electron temperature-based metallicity for star-forming galaxies in a wide mass range

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Research in Astronomy and Astrophysics 2014年第7期14卷 875-890页

作者： Wei-Bin Shi Yan-Chun Liang Xu Shao Xiao-Wei Liu Gang Zhao Francois Hammer Yong Zhang hector Flores Gui-Ping Ruan Li Zhou Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsShandong University Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences University of Chinese Academy of Sciences Kavli Institute for Astronomy and Astrophysics Peking University GEPI Observatoire de Paris-Meudon Department of Physics University of Hong Kong

We select 947 star-forming galaxies from SDSS-DR7 with [O III]λ4363emission lines detected at a signal-to-noise ratio larger than 5σ. Their electron temperatures and direct oxygen abundances are then determined. We compare the results from different methods. t2, the electron temperature in the low ionization region, estimated from t3, that in the high ionization region, is compared using three analysis relations between t2- t3. These show obvious differences, which result in some different ionic oxygen abundances. The results of t3, t2, O＋＋/H＋and O＋/H＋derived by using methods from IRAF and literature are also compared. The ionic abundances O＋＋/H＋are higher than O＋/H＋for most cases. The different oxygen abundances derived from Teand the strong-line ratios show a clear discrepancy, which is more obvious following increasing stellar mass and strong-line ratio R23. The sample of galaxies from SDSS with detected [O III]λ4363 have lower metallicites and higher star formation rates, so they may not be typical representatives of the whole population of galaxies. Adopting data objects from Andrews ＆ Martini, Liang et al. and Lee et al. data, we derive new relations of stellar mass and metallicity for star-forming galaxies in a much wider stellar mass range： from 106 M to 1011 M.

关键词： galaxies: abundances -- galaxies: evolution -- galaxies: ISM -- galax-ies: spiral -- galaxies: starburst -- galaxies: stellar content

Detection of presumed genes encoding beta-lactamases by sequence based screening of metagenomes derived from Antarctic microbial mats

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Frontiers of Environmental Science & Engineering 2019年第3期13卷 173-184页

作者： Gaston Azziz Matias Gimenez hector Romero Patricia M. Valdespino-Castillo Luisa I. Falcon Lucas A. M. Ruberto Walter P. Mac Cormack Silvia Batista Molecular Microbiology Unit Clemente Estable Biological Research Insitute Montevideo 11600 Uruguay Microbiology Laboratory Faculty of Agronomy UdelaR Montevideo 12900 Uruguay Genome Organization and Evolution Laboratory Ecology and Evolution Department Faculty of Sciences UdelaR Montevideo 11400 Uruguay Molecular Biophysics and Integrated Bioimaging BSISB Imaging Program Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Bacteial Ecology Laboratory Ecology Institute National Autonomous University of Mexico CDMX 04510 Mexico UN AM Yucatan Technology and Science Park Merida 97302 Mexico Argentine Antarctic Institute Buenos Aires 1650 Argentina Biotechnology Unit Faculty of Pharmacy and Biochemistry Nanobiotec Institute UBA-CONICET Buenos Aires 1113 Argentina

Analysis of environmental samples for bacterial antibiotic resistance genes may have different objectives and analysis strategies. In some cases, the purpose was to study diversity and evolution of genes that could be grouped within a mechanism of antibiotic resistance. Different protocols have been designed for detection and confirmation that a functional gene was found. In this study, we present a sequence-based screening of candidate genes encoding beta-lactamases in 14 metagenomes of Antarctic microbial mats. The samples were obtained from different sites, representing diverse biogeographic regions of maritime and continental Antarctica. A protocol was designed based on generation of Hidden Markov Models from the four beta-lactamase classes by Ambler classification, using sequences from the Comprehensive Antibiotic Resistance Database (CARD). The models were used as queries for metagenome analysis and recovered contigs were subsequently annotated using RAST. According to our analysis, 14 metagenomes analyzed contain A, B and C beta-lactamase genes. Class D genes, however, were identified in 11 metagenomes. The most abundant was class C (46.8%), followed by classes B (35.5%), A (14.2%) and D (3.5%). A considerable number of sequences formed clusters which included, in some cases, contigs from different metagenomes. These assemblies are clearly separated from reference clusters, previously identified using CARD beta-lactamase sequences. While bacterial antibiotic resistance is a major challenge of public health worldwide, our results suggest that environmental diversity of beta-lactamase genes is higher than that currently reported, although this should be complemented with gene function analysis.

关键词： Beta-lactamases Antibiotic resistance coding genes Metagenomes Antarctic microbial mats