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Effects of N-acetylcysteine on growth,viability and reactive oxygen species levels in small antral follicles cultured in vitro

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Asian pacific Journal of Reproduction 2023年第1期12卷 42-48页

作者： Efigênia B.Cordeiro Bianca R.Silva Laís R.f.M.Paulino Pedro A.A.Barroso Laryssa G.Barrozo Miguel f.de lima Neto JoséR.V.Silva Laboratory of Biotechnology and Physiology of Reproduction Federal University of CearaAv.Comandante Maurocélio Rocha Ponte 10062041-040SobralCEBrazil

Objective:To investigate the effects of different concentrations of N-acetylcysteine on follicular growth and morphology,as well as on viability,levels of reactive oxygen species(ROS)and meiotic progression of oocytes from in vitro cultured bovine early antral ***:Isolated early antral follicles(about 500μm)were cultured in TCM-199+alone or supplemented with 1.0,5.0 or 25.0 mM N-acetylcysteine at 38.5℃with 5%CO_(2) for 8 *** diameters were evaluated at day 0,4 and 8 of *** the end of culture,the levels of ROS,chromatin configuration and viability(calcein-AM and ethidium homodimer-1 staining)were investigated in the cumulus-oocyte *** of follicle diameters between treatments were *** on percentages of morphologically normal follicles,growth rates and chromatin configuration in different treatments were ***:An increase in follicular diameters after culture in all treatments was observed,except for follicles cultured with 25.0 mM *** microscopy showed that oocytes cultured in all treatments were stained positively with calcein AM,and that 5.0 mM N-acetylcysteine reduced fluorescence for ethidium *** levels of ROS in oocytes from follicles cultured with 1.0 mM N-acetylcysteine showed a significant reduction compared to other *** presence of N-acetylcysteine in culture medium did not influence the rates of oocyte at the germinal vesicle ***:N-acetylcysteine at concentrations of 1.0 and 5.0 mM reduces ROS levels and staining for ethidium homodimer-1 in in vitro cultured follicles,respectively,while 25.0 mM N-acetylcysteine decreases follicular growth and the percentages of continuously growing follicles.

关键词： Antioxidant N-acetylcysteine Antral follicles Bovine Reactive oxygen species

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A KNN Undersampling Approach for Data Balancing

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Journal of Intelligent Learning Systems and Applications 2015年第4期7卷 104-116页

作者： Marcelo Beckmann Nelson f. f. Ebecken Beatriz S. L. Pires de lima Civil Engineering Program/COPPE Federal University of Rio de Janeiro Rio de Janeiro Brazil

In supervised learning, the imbalanced number of instances among the classes in a dataset can make the algorithms to classify one instance from the minority class as one from the majority class. With the aim to solve this problem, the KNN algorithm provides a basis to other balancing methods. These balancing methods are revisited in this work, and a new and simple approach of KNN undersampling is proposed. The experiments demonstrated that the KNN undersampling method outperformed other sampling methods. The proposed method also outperformed the results of other studies, and indicates that the simplicity of KNN can be used as a base for efficient algorithms in machine learning and knowledge discovery.

关键词： Machine Learning Class Overlaping Imbalanced Datases

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Electron-Domain Wall Interaction with a ferromagnetic Spherical Domain Wall

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Journal of Modern Physics 2016年第13期7卷 1635-1643页

作者： Leonardo dos Santos lima Departamento de física e Matemática Centro Federal de Educa&ccedil&atildeo Tecnológica de Minas Gerais Belo Horizonte Brazil

The interaction between an electron with a three-dimensional domain wall was investigated using the Born’s expansion of the S scattering matrix. We obtain an influence of the scattering of the electron with the ferromagnetic domain wall in the spin wave function of the electron with the aim to generate the knowledge about the state of the electron spin after the scattering. It relates to the recent problem of generation of the spin polarized electric current. We also obtain the contribution of the electron-wall domain interaction on the electric conductivity , through the wall domain, where we have obtained a peak of resonance in the conductivity for one value of .

关键词： Electron Scattering Domain-Wall ferromagnet

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On the Impact of Brazil's Largest Recent Oil Spill on Regional Oceans

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Sustainable Marine Structures 2021年第2期3卷 1-14页

作者： Liana de figueiredo Mendes Patricia Pinheiro Beck Eichler Tatiana Leite Ana Beatriz Alves Bennemann Clara de Souza Melo andressa lima f.rreira Khalil Bow Ltaif Garcia Luzia Liniane do Nascimento Silva Christofer Paul Barker Helenice Vital Moab Praxedes Gomes Priscila f.M.Lopes Department of Ecology Federal University of Rio Grande do Norte(UFRN)University CampusLagoa Nova59072-970 NatalRNBrazil Graduate Program in Geodynamics and Geophysics(PPGG) Laboratory of Marine Geology and Geophysics and Environmental MonitoringFederal University of Rio Grande do Norte 0JFRN)University CamposLagoa Nova59072-970 NatalRNBrazil ***(California USA) Department of Ecology and Zoology Federal University of Santa CatarinaTrindade88040-900FlorianopolisSCBrazil

In 2019,an oil spill in Brazil,of unknown origin,severely impacted coastal environs with the worst environmental disaster ever recorded in any tropical coastal region globally severely damaging South Pirangi Reef area in the state of Rio Grande do Norte(RN).Here we discuss acute and chronic impacts including chemical contamination and economic consequences all over the world and show some evidence of the oil spill in this biodiverse ***,the lapse between the moment of the disastei;and the action to manage it,was hampered by a political agenda coinciding with local and global tragedies that redirected public *** almost 2 years have passed still without the offending party identification or culpability;and poor communities may continue to absorb its deleterious impacts for decades without consideration or *** disaster occurred during the Brazilian government's current issues involving extensive environmental mismanagement,resulting in a slow response from an inept *** is with urgent necessity to spotlight this tragedy in this unique and sensitive reef habitat experiencing the ongoing damaging effects that include socio-economic losses not yet addressed.

关键词： Environmental impacts Socioeconomic losses Government Brazilian coast Oil spill Disaster

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Green CoNi_(2)S_(4)/porphyrin decorated carbon-based nanocomposites for genetic materials detection

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Journal of Bioresources and Bioproducts 2021年第3期6卷 215-222页

作者： Mohammad Reza Saeb Navid Rabiee farzad Seidi Bahareh farasati far Mojtaba Bagherzadeh Eder C.lima Mohammad Rabiee Universitéde Lorraine CentraleSupélecLMOPSF57000 MetzFrance Department of Chemistry Sharif University of TechnologyTehranIran Provincial Key Lab of Pulp&Paper Sci and Tech and Joint International Research Lab of Lignocellulosic Functional MaterialsNanjing Forestry UniversityNanjing 210037China Department of Chemistry Iran University of Science and TechnologyTehranIran Institute of Chemistry Federal University of Rio Grande do Sul(UFRGS)Av.Bento Goncalves 9500Postal Box15003ZIP91501-970 Brazil Biomaterial Group Department of Biomedical EngineeringAmirkabir University of TechnologyTehranIran

A one-pot synthesis method was conceptualized and implemented to develop green carbon-based nanocomposites working as *** was synthesized to adorn the surface of nanocomposites making them highly sensitive for giving rise to π-π interactions between the genetic materials,proteins and porphyrin *** hydrogen bond formed between the proteins(analytes)and the nitrogen in the porphyrin structure as well as the surface hydroxyl groups was equally *** this context,different forms of porphyrins were incorporated to explore the interrelationship between the surface morphology and the ability of detection of genetic material and/or proteins by the aid of the synthesized *** phenomenon was conceptualized to optimize the interactions between the biomolecules and the substrate by reaching significant biosensor application in the presence of Anti-cas9 protein and sgRNA(concentration changed between 10 and 500 n mol/L).Almost full quenching of fluorescence emission was observed after addition of 300 n mol/L of Anti-cas9 protein and 250 n mol/L of ***,CoNi_(2)S_(4)provided 12%-29%cytotoxicity in both HEK-293 and PC12 cell lines.

关键词： Biosensor Biomedicine Anti-cas9 Green nanocomposite sgRNA

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Entanglement in the Quantum Phase Transition of the Half-Integer Spin One-Dimensional Heisenberg Model

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Journal of Modern Physics 2015年第15期6卷 2231-2238页

作者： Leonardo S. lima Departamento de física e Matemática Centro Federal de Educa&#231 o Tecnológica de Minas Gerais Belo Horizonte MG Brazil

We use the Bethe’s ansatz method to study the entanglement of spinons in the quantum phase transition of half integer spin one-dimensional magnetic chains known as quantum wires. We calculate the entanglement in the limit of the number of particles . We obtain an abrupt change in the entanglement next the quantum phase transition point of the anisotropy parameter ?from the gapped phase ?to gapless phase .

关键词： Entanglement Quantum-Phase-Transition One-Dimensional Heisenberg Model Spin One-Half

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Effect of alcoholic extract of Lepidium meyenii (Maca) on testicular function in male rats

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Asian Journal of Andrology 2003年第4期5卷 349-352页

作者： Gustavo f. Gonzales Julio Rubio Arturo Chung Manuel Gasco León Villegas Department of Biological and physiological Sciences faculty of Sciences and Philosophy and Instituto de Investigaciones de la Altura Department of Biochemistry Molecular Biology and Pharmacology Universidad Peruana Cayetano HerediaLima Peru

Aim: To evaluate the effect of the alcoholic extract of Lepidium meyenii (Maca) on the spermatogenesis in male rats. Methods: In Holtzman rats, Maca alcoholic extract (5%) was given by oral route at doses of 48 mg/day or 96 mg/day for 7 days, 14 days and 21 days. Testicular function was assessed by measurements of lengths of different stages of seminiferous epithelia and by epididymal sperm count. Results: Ethanolic extract of Maca increased the length of stages IX-XI of seminiferous epithelium at treatment day 7, day 14 and day 21. Progression of spermatogenesis was evident only after day 21 when lengths of stages XII-XIV of seminiferous epithelium were increased; at day 7 and day 14, no important change in spermatogenesis was observed. Epididymal sperm count was increased with 48 mg/day at all times. With 96 mg/day an increase in sperm count was observed at day 7, but it was reduced at day 14 and day 21 of treatment. Serum testosterone levels were not affected. Conclusion: The alcoholic extract of Maca activates onset ant progression of spermatogenesis at 48 mg/day or 96 mg/day in rats.

关键词： Lepidium meyenii transillumination spermatogenesis sperm count

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High chromosomal evolutionary dynamics in sleeper gobies(Eleotridae)and notes on disruptive biological factors in Gobiiformes karyotypes(Osteichthyes,Teleostei)

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Marine Life Science & Technology 2021年第3期3卷 293-302页

作者： Simião Alefe Soares da Silva Paulo Augusto de lima-filho Clóvis Coutinho da Motta-Neto Gideão Wagner Werneck félix da Costa Marcelo de Bello Cioffi Luiz Antônio Carlos Bertollo Wagner franco Molina Departamento de Biologia Celular e Genética Centro de BiociênciasUniversidade Federal do Rio Grande do NorteNatalRN59.078-970Brazil Instituto federal de Ciência e Tecnologia do Rio Grande do Norte Santa CruzRN59200-000Brazil Departamento de Genética e Evolução Universidade Federal de São CarlosRodovia Washington LuísKm 235São CarlosSP13.565-905Brazil

The order Gobiiformes is made up of more than 2200 species,representing one of the most diverse groups among teleost *** biological causes for the tachytelic karyotype evolution of the gobies have not yet been fully *** we expanded cytogenetic data for the Eleotridae family,analyzing the neotropical species Dormitator maculatus,Eleotris pisonis,Erotelis smaragdus,and Guavina *** addition,a meta-analytical approach was followed for elucidating the karyotype diversification versus biological aspects(habitat and egg type)of the *** species *** and *** present 2n=46 acrocentric chromosomes(Nf=46),*** 2n=46(36sm+4st+6a;Nf=86),and ***,the most divergent karyotype,with 2n=52 acrocentric chromosomes(Nf=52).Besides numeric and structural diversification in the karyotypes,the mapping of rDNAs and microsatellites also showed noticeable numerical and positional variation,supporting the high chromosomal evolutionary dynamism of these *** Gobiiformes,karyotype patterns which are more divergent from the basal karyotype(2n=46a)are associated with characteristics less effective to dispersion,such as the benthic *** adaptive characteristics,connected with the organization of the repetitive DNA content in the chromosomes,likely play a synergistic role in the remarkable karyotype diversification of this group.

关键词： Chromosome evolution Dispersive potential Goby Karyotype diversification Microsatellites rDNA

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Habitat specialization and phylogenetic structure of tree species in a coastal Brazilian white-sand forest

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Journal of Plant Ecology 2014年第2期7卷 134-144页

作者： Alexandre A.de Oliveira Alberto Vicentini Jerome Chave Camila de T.Castanho Stuart J.Davies Adriana M.Z.Martini Renato A.f.lima Ricardo R.Ribeiro Amaia Iribar Vinicius C.Souza Instituto de Biociências Universidade de São PauloRua do Matão321Travessa 14São PauloSP 0550890Brazil Instituto Nacional de Pesquisas da Amazônia Av.AndréAraújo2936CP 478.ManausAM 69060001Brazil Evolution et DiversitéBiologique Bâtiment 4R1 UniversitéPaul Sabatier118 route de Narbonne31062 ToulouseFrance Smithsonian Tropical Research Institute PO Box 37012WashingtonDC 20013-7012USA ESALQ Universidade de São Paulo.Avenida Pádua Dias11PiracicabaSP 13418900Brazil

Aims The coastal Brazilian rainforest on white-sand(restinga)ranks among the most fragmented forest types in the tropics,owing to both the patchy distribution of sandy soils and widespread coastal development *** we study the environmental and evolutionary determinants of a forest tree assemblage at a single restinga forest in Southeastern *** also explore the ability of competing hypotheses to explain the maintenance of species diversity in this forest type,which includes contrasting extremes of edaphic conditions associated with flooding *** The study was conducted in a white-sand forest permanent plot of 10.24 ha on the coastal plain of Southeastern *** plot was divided into 256 quadrats of 20×20 m,which were classified into two main edaphic habitats(flooded and drained).Trees with a diameter≥1 cm at breast height were *** assembled DNA sequence data for each of the 116 morphospecies recognized using two chloroplast markers(rbcL and matK).A phylogenetic tree was obtained using the maximum likelihood method,and a phylogenetic distance matrix was produced from an ultrametric *** analyzed similarity in floristic composition and structure between habitats and related them to cross-plot distances using permutation *** model torus shift simulations were performed to obtain a statistical significance level for habitat association for each *** phylogenetic structure for the two habitats and for each 20×20 m quadrat was calculated using the mean phylogenetic distance weighted by species abundance and checked for significance using the standardized effect size generated by 5000 randomizations of phylogenetic tip *** findings Our results indicate that partitioning among edaphic habitats is important for explaining species distributions and coexistence in restinga *** distributions within the plot were found to be non-random:there was greater floristic similarity within than betwe

关键词： habitat association torus-translation test phylogenetic community structure niche partitioning edaphic condition

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Cycloheximide prevents production of arresting,a fraction of 30-50 kDa obtained from seminiferous tubule conditioned medium

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Asian Journal of Andrology 2004年第4期6卷 359-364页

作者： Gustavo f.Gonzales Stella Hartinger Yetssy flores Kelly Zárate Pedro Yi Instituto de Investigations de la Altura Department of Biological and Physiological SciencesDepartment of Biological and Physiological SciencesDepartment of Biological and Physiological SciencesFaculty of Veterinary Medicine and Animal Sciences Department of Biological and Physiological Sciences and and and and Universidad Peruana Cayetano Heredia. Postal Office 1843. Lima Peru

Aim: To evaluate the effect of a protein synthesis inhibitor cycloheximide on arresting activity in spermato-genesis and sperm count in male rats. Methods: The study used seminiferous tubule (ST) segments from adult rats cultured in vitro with or without cycloheximide to condition culture media, which have been concentrated, size fractioned (30-50 kDa) and administered 7 days to adult rats by intraperitoneal injections. The effects on testicular and epididymal weights, spermatogenesis and epididymal sperm count were determined. Results: The fraction (30-50 kDa), named arresting, obtained from the culture without cycloheximide decreased testicular and epididymal weights (Pficantly. Study of the spermatogenic cycle by transillumination showed spermatogenic arrest at stage VII in rats treated with arresting compared to that observed in controls. The length of stage VII in the group receiving the seminiferous tubules culture media with cycloheximide (30-50 KDa CHX-STCM fraction) was similar to control. Conclusion: The difference in the effect may be the result of the presence or absence of arresting, a protein secreted by the tubules.

关键词： cycloheximide arresting conditioned medium seminiferous tubule sperm production transillumination

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