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Variational Principle for a Schrodinger Equation with Non-Hermitian Hamiltonian and Position-dependent Mass

Communications in Theoretical Physics 2015年第3期63卷 275-278页

作者： A.R.Plastino C.Vignat A.Plastino cebio y secretaria de investigacion Universidad Nacional del Noroeste de la Prov.de Buenos AiresUNNOBA-ConicetSaenz Pena 456Junin Argentina department of Mathematics Tulane University L.S.S. SupelecUniversity of Orsay IFLP-CCT-CONICET Universidad Nacional de La PlataC.C.727La Plata 1900Argentina

A classical field theory for a Schrodinger equation with a non-Hermitian Hamiltonian describing a particle with position-dependent mass has been recently advanced by Nobre and Rego-Monteiro(NR)[***.A 88(2013)032105].This field theory is based on a variational principle involving the wavefunction Ψ(x,t) and an auxiliary fieldΦ{x,t).It is here shown that the relation between the dynamics of the auxiliary field Φ(x,t) and that of the original wavefunction Ψ(x,t) is deeper than suggested by the NR ***,we formulate a variational principle for the aforementioned Schrodinger equation which is based solely on the wavefunction Ψ(x,t).A continuity equation for an appropriately defined probability density,and the concomitant preservation of the norm,follows from this variational principle via Noether's ***,the norm-conservation law obtained by NR is reinterpreted as tie preservation of the inner product between pairs of solutions of the variable mass Schrodinger equation.

关键词： Schrodinger equation non-hermitian Hamiltonian position-dependent mass classical field theory

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The largest dengue outbreak in Argentina and spatial analyses of dengue cases in relation to a control program in a district with sylvan and urban environments

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Asian Pacific Journal of Tropical Medicine 2018年第3期11卷 227-234页

作者： Aníbal E Carbajo Alejandra Rubio María J Viani María R Colombo Laboratorio de Eoclogía de Enfermedades Transmitidas por Vectores Instituto de Investigación e Ingeniería AmbientalUniversidad Nacional de General San Martín Consejo Nacional de investigaciones Científicas y Técnicas secretaria de Política Sanitaria y desarrollo Humano Municipio de Tigre

Objective: To analyze the largest outbreak of dengue in Argentina in the municipality of Tigre during 2016, through detailed spatial analyses of the occurrence of cases in relation to demographic factors and vector control actions. Methods: detailed and georreferenced data on dengue cases with laboratory results(NS1 or IgM) were analyzed. The occurrences of imported and autochthonous cases by census tract were modeled using demographic variables(population by age class, proportion of foreigners, proportion with university grade, proportion of males), dwelling variables(number of homes, proportion of dwellings with latrine, number of dwellings, proportion of houses, proportion of flats, proportion of slums) and census tract area as explanatory variables. The probability of occurrence of autochthonous and imported cases was modeled separately. The spatio-temporal occurrence of cases was studied in relation to focal and perifocal control actions(involving education campaigns, removal of Aedes aegypti breeding sites and exhaustive insecticide spraying) to assess the efficiency in stopping autochthonous cases spreading. Results: All autochthonous cases occurred in the urban environment with no sylvan cases. The majority of the imported cases registered came from Paraguay and Northeastern Argentina. The age structure of imported and autochthonous cases did not differ from the age structure of the municipality, while that of the negative cases *** studied spatially, the occurrence of imported cases by census tract was mildly associated with a higher proportion of foreign population and more people at active age, while occurrence of autochthonous cases was not significantly associated with any of the studied *** census tracts with laboratory confirmed results, the models showed higher probability of autochthonous cases related to higher population density and population age structure. The clustering of autochthonous cases was generally mild, with prevailing i

关键词： Aedes aegypti Vector-borne diseases Vector control dengue epidemic

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A Saccharomyces cerevisiae RC016-based feed additive reduces liver toxicity,residual aflatoxin B1 levels and positively influences intestinal morphology in broiler chickens fed chronic aflatoxin B1-contaminated diets

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Animal Nutrition 2020年第1期6卷 31-38页

作者： Valeria Poloni Alejandra Magnoli Analía Fochesato Andrea Cristofolini Matias Caverzan Cecilia Merkis Maríana Montenegro Lilia Cavaglieri departamento de Microbiología e Inmunología Universidad Nacional de Río CuartoRío CuartoArgentina Consejo Nacional de investigaciones Científicas y Tecnólogicas(CONICET) Buenos AiresArgentina departamento de Microscopía Electrónica Universidad Nacional de Río CuartoRío CuartoArgentina Centro de investigaciones y Transferencia Villa María Universidad Nacional de Villa MaríaVilla MaríaArgentina

The present study was conducted to investigate the ability of Saccharomyces cerevisiae RC016(Sc)-based feed additive to reduce liver toxicity,residual aflatoxin B1(AFB1)levels and influence intestinal structure in broiler chickens fed chronic aflatoxin B1-contaminated diets.A total of 100 one-day-old male commercial line(Ross)broiler chickens were divided into 4 treatments,with 5 pens per treatment and 5 broiler chickens per *** were randomly assigned to 4 treatments,which were namely treatment 1(T1),control diet(CD);T2,CD+Sc at 1 g/kg;T3,CD+AFB1 at 100μg/kg;T4,CD+Sc at 1 g/kg+AFB1 at100μg/*** liver histopathology of broiler chickens fed diets with AFB1 showed diffused microvacuolar fatty *** addition of Sc showed normal hepatocytes similar to the *** small intestine villi from AFB1 group showed atrophy,hyperplasia of goblet cells,prominent inflammatory infiltrate and *** contrast,the small intestine villi from birds that received the yeast plus AFB1 showed an absence of inflammatory infiltrate,and atrophy;moreover,a lower number of goblet cells compared to the groups with AFB1 was *** morphometric intestine studies showed that a significant decrease(Pypt depth values when Sc was applied to AFB1-contaminated *** the intestinal villus height and apparent adsorption area did not show significant differences(P>0.05),there was a tendency to improve these *** residual levels of AFB1 in livers were significantly reduced(Pdemonstrated that the addition of Sc alone or in combination with AFB1 in the broiler chicken diets had a beneficial effect in counteracting the toxic effects of AFB1 in livers besides improving the histomorphometric parameters and modulating the toxic effect of AFB1 in the intestine.

关键词： Aflatoxin B1 Broiler chickens Histomorphometry Histopathology toxic effects

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New approach to assess sperm DNA fragmentation dynamics： Fine-tuning mathematical models

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Journal of Animal Science and Biotechnology 2017年第3期8卷 592-600页

作者： Isabel Ortiz Jesus Dorado Jane Morrell Jaime Gosalvez Francisco Crespo Juan M.Jimenez Manuel Hidalgo Veterinary Reproduction Group Department of Animal Medicine and Surgery Faculty of Veterinary Medicine University of Cordoba 14071 Cordoba Spain department of Clinical Sciences Division of Reproduction Swedish University of Agricultural Sciences Box 7054 SE-75007 Uppsala Sweden department of Biology Universidad Aut6noma de Madrid 28049 Madrid Spain department of Reproduction Centro Militar de Cria Caballar (FESCCR-Ministry of Defense) 05005 Avila Spain department of Chemistry and Physics of Materials University of Salzburg Hellbrunner StraBe 34/111 A-5020 Salzburg Austria

Background： Sperm DNA fragmentation（sDF） has been proved to be an important parameter in order to predict in vitro the potential fertility of a semen sample. Colloid centrifugation could be a suitable technique to select those donkey sperm more resistant to DNA fragmentation after thawing. Previous studies have shown that to elucidate the latent damage of the DNA molecule, sDF should be assessed dynamically, where the rate of fragmentation between treatments indicates how resistant the DNA is to iatrogenic damage. The rate of fragmentation is calculated using the slope of a linear regression equation. However, it has not been studied if s DF dynamics fit this model. The objectives of this study were to evaluate the effect of different after-thawing centrifugation protocols on sperm DNA fragmentation and elucidate the most accurate mathematical model（linear regression, exponential or polynomial） for DNA fragmentation over time in frozen-thawed donkey ***： After submitting post-thaw semen samples to no centrifugation（UDC）, sperm washing（SW） or single layer centrifugation（SLC） protocols, sD F values after 6 h of incubation were significantly lower in SLC samples than in SW or *** of determination（R-2） values were significantly higher for a second order polynomial model than for linear or exponential. The highest values for acceleration of fragmentation（aSDF） were obtained for SW, fol owed by SLC and ***： SLC after thawing seems to preserve longer DNA longevity in comparison to UDC and SW. Moreover,the fine-tuning of models has shown that sDF dynamics in frozen-thawed donkey semen fit a second order polynomial model, which implies that fragmentation rate is not constant and fragmentation acceleration must be taken into account to elucidate hidden damage in the DNA molecule.

关键词： Colloid centrifugation Dynamics Fine-tuning Mathematical models Sperm DNA fragmentation

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Large edge magnetism in oxidized few-layer black phosphorus nanomeshes

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Nano Research 2017年第2期10卷 718-728页

作者： yudai Nakanishi Ayumi Ishi Chika Ohata David Soriano Ryo Iwaki Kyoko Nomura~ Miki Hasegawa Taketomo Nakamura Shingo Katsumoto Stephan Roche Junji Haruyama Faculty of Science and Engineering Aoyama Gakuin University 5- I0-1 Fuchinobe Sagamihara Kanagawa 252-5258 Japan Chemistry and Biological Science Aoyama Gakuin University 5-10-1 Fuchinobe Sagamihara Kanagawa 252-5258 Japan Catalan Institute of Nanoscience and Nanotechnology (ICN2) CSIC and The Barcelona Institute of Science and Technology Campus UAB Bellaterra 08193 Barcelona Spain Institucio Catalana de Recercai Estudis Avancats (ICREA) 08010 Barcelona Spain Institute for solid state physics The University of Tokyo 5- I-5 Kashiwanoha Kashiwa Chiba 277-8581 Japan

The formation and control of a room-temperature magnetic order in two- dimensional （2D） materials is a challenging quest for the advent of innovative magnetic- and spintronic-based technologies. To date, edge magnetism in 2D materials has been experimentally observed in hydrogen （H）-terminated graphene nanoribbons （GNRs） and graphene nanomeshes （GNMs）, but the measured magnetization remains far too small to allow envisioning practical applications. Herein, we report experimental evidences of large room-temperature edge ferromagnetism （FM） obtained from oxygen （O）-terminated zigzag pore edges of few-layer black phosphorus （P） nanomeshes （BPNMs）. The magnetization values per unit area are -100 times larger than those reported for H-terminated GNMs, while the magnetism is absent for H-terminated BPNMs. The magnetization measurements and the first-principles simulations suggest that the origin of such a magnetic order could stem from ferromagnetic spin coupling between edge P with O atoms, resulting in a strong spin localization at the edge valence band, and from uniform oxidation of full pore edges over a large area and interlayer spin interaction. Our findings pave the way for realizing high-efficiency 2D flexible magnetic and spintronic devices without the use of rare magnetic elements.

关键词： black phosphorus nanomesh edge magnetism spintronics zigzag edge oxygen termination rare-metal free

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