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Asian Journal of Andrology 2017年第6期19卷 715-716页

作者： Candela Rocio Gonzailez Cristian Alvarez Sedo Florencia Nodar Sergio Papier alfredo daniel vitullo Research Center of Biomedical Biotechnology Environmental and Diagnostic Studies Maim6nides University Hidalgo 775 1405 Buenos Aires Argentina National Scientific and Technical Research Council (CONICET) Argentina Laboratory of Reproductive Biology and Genetics (CEGyR) Viamonte 1432 1055 Buenos Aires Argentina.

Dear Editor, Infertility is a major health problem affecting 10%-15% of couples seeking to have children, and a male factor can be identified in about half of these cases.1 Nonobstructive azoospermia is one of the causes of male infertility （10%）, resulting from testicular failure？ The most common histological patterns in these patients are hypospermatogenesis （HS）, maturation arrest （MA）, and Sertoli cell-only syndrome （SCO）.3

关键词： Simultaneous azoospermia-family testicular

Altered Expression of Aromatase, Estrogen Receptors and Progesterone Receptors in Human Leydig Cell Hyperplasia

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Advances in Bioscience and Biotechnology 2015年第1期6卷 1-10页

作者： Candela Rocío González Pablo Ignacio Felipe Inserra Claudio Terradas Roberto Ponzio Elisa Puigdomenech Oscar Levalle alfredo daniel vitullo Ricardo Saúl Calandra Silvia Ines Gonzalez-Calvar Research Center of Biomedical Biotechnology Environmental and Diagnostic Studies Maimónides University Buenos Aires Argentina División Endocrinología Hospital Durand Buenos Aires Argentina Facultad de Medicina Universidad de Buenos Aires Buenos Aires Argentina Instituto Medico PREFER Calle 995 No 2348 San Martin Argentina Laboratorio de Endocrinología Molecular de la Reproducción Instituto de Biología y Medicina Experimental (CONICET) Buenos Aires Argentina Laboratorio de Endocrinología Molecular de la Reproducción Instituto de Biología y Medicina Experimental (CONICET) Facultad de Medicina Universidad de Buenos Aires Buenos Aires Argentina

Testicular function is regulated by pituitary hormones and also by paracrine and autocrine factors. A number of reports have pointed out the importance of estrogens and progesterone in male reproductive tract. Recently, we have reported in testicular biopsies from men with Sertoli Cell Only Syndrome (SCO) or Hypospermatogenesis (H) with Leydig cell hyperplasia (LCH) an increase in the expression of the TGFB1 and its receptors ALK1 and endoglin, which are involved in the proliferation of Leydig cells. The aim of the present work was to analyze the expression of aromatase, estrogen and progesterone receptors (ERs, PR) in pathological testicular biopsies with SCO or H with and without LCH. The ERs and CYP19 proteins were detected in the Leydig cells from all pathological biopsies analyzed. Biopsies with SCO or H with LCH showed an increment in the immunostaining of CYP19 and ERs in the Leydig cells respect to biopsies without LCH. The gene expression of CYP19 was increased in SCO or H biopsies with LCH respect to SCO and H biopsies without LCH. PR was localized in Leydig cells and showed a significant increment in biopsies with LCH respect from biopsies without LCH. The gene expression of both PRA and PRB was increased in biopsies with LCH respect to biopsies without LCH. In concussion, alterations in the gene expression of aromatase, ERs, and PR and the likely interactions of these systems with locally produced factors such as growth factors and cytokines, might lead to Leydig cell proliferation in testicular pathology.

关键词： Aromatase Progesterone Estrogen Leydig

Elastic modulus and thermal stress in coating during heat cycling with different substrate shapes

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Frontiers of Mechanical Engineering 2015年第3期10卷 294-300页

作者： daniel GAONA alfredo VALAREZO Mechanical Engineering Universidad San Francisco de Quito QuitoEcuador Material Science and Engineering Universidad San Francisco de QuitoQuito Ecuador

The elastic modulus of a deposit （Ed） can be obtained by monitoring the temperature （AT） and curvature （Ak） of a one-side coated long plate, namely, a onedimensional （1D） deformation model. The aim of this research is to design an experimental setup that proves whether a 1D deformation model can be scaled for complex geometries. The setup includes a laser displace- ment sensor mounted on a robotic arm capable of scanning a specimen surface and measuring its deformation. The reproducibility of the results is verified by comparing the present results with Stony Brook University Laboratory＇s results. The Ak-AT slope error is less than 8%, and the Eo estimation error is close to 2%. These values reveal the repeatability of the experiments. Several samples fabri- cated with aluminum as the substrate and 100MXC nanowire （Fe and Cr alloy） as the deposit are analyzed and compared with those in finite element （FE） simula- tions. The linear elastic behavior of 1D （flat long plate） and 2D （squared plate） specimens during heating/cooling cycles is demonstrated by the high linearity of all Ak-AT curves （over 97%）. The Ed values are approximately equal for 1D and 2D analyses, with a median of 96 GPa and standard deviation of 2 GPa. The correspondence between the experimental and simulated results for the 1D and 2D specimens reveals that deformation and thermal stress in coated specimens can be predicted regardless of specimen geometry through FE modeling and by using the experimental value of Ed. An example of a turbine-blade- shaped substrate is presented to validate the approach.

关键词： in-plane Young’s modulus curvature temperature thermal stress coating

BTZ Quasinormal Frequencies as Poles of Green’s Function

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Journal of Applied Mathematics and Physics 2018年第6期6卷 1170-1178页

作者： alfredo López-Ortega daniel Mata-Pacheco Departamento de Fisica Escuela Superior de Fisica y Matemáticas Instituto Politécnico Nacional Mexico City México

Based on the well known fact that the quasinormal frequencies are the poles of the frequency domain Green’s function we describe a method that allows us to calculate exactly the quasinormal frequencies of the Klein-Gordon field moving in the three-dimensional rotating Bañados-Teitelboim-Zanelli black hole. These quasinormal frequencies are already published and widely explored in several applications, but we use this example to expound the proposed method of computation. We think that the described procedure can be useful to calculate exactly the quasinormal frequencies of classical fields propagating in other backgrounds. Furthermore, we compare with previous results and discuss some related facts.

关键词： Quasinormal Modes Klein-Gordon Field BTZ Black Hole

Lumbar Synovial Cyst, Literature Review: Challenges of the Surgical Management, the Role of Minimal Invasive Techniques and Endoscopy

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Surgical Science 2023年第11期14卷 681-693页

作者： Marcel Sincari alfredo Carvalho André Nunes Mark daniel Sincari Neurosurgery Department Centro Hospitalar Tondela-Viseu Viseu Portugal Orthopedy Department Centro Universitário Cova de Beira Covilh&#227 Portugal Neurosurgery Department Hospital Prenda Luanda Angola Faculty of Medicine University of Coimbra Coimbra Portugal

The management of symptomatic lumbar synovial cysts is still a challenge and a matter of debate with no existing strong consensus. There are different treatment techniques and strategies, the most debated matter is to fuse or not to fuse, efficiency of less invasive techniques. One of our purposes was to provide an updated review of a literature about treatment of juxta facet synovial cysts and as standard surgical strategies are inconsistent, we present a small series of patients treated using different approaches, most of them were treated with MISS techniques, endoscopy, providing good results.

关键词： Lumbar Synovial Cyst Lumbar Decompression Facet Joint

Lovastatin as a supplement to mitigate rumen methanogenesis:an overview

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Journal of Animal Science and Biotechnology 2022年第2期13卷 353-364页

作者： Amaury Ábrego-Gacía Héctor M.Poggi-Varaldo Vania Robles-González Teresa Ponce-Noyola Graciano Calva-Calva Elvira Ríos-Leal daniel Estrada-Bárcenas alfredo Mendoza-Vargas Department of Biotechnology and Bioengineering CINVESTAV-IPNP.O.Box 17-74007000 Mexico CityMexico Environmental Biotechnology and Renewable Energies Group CINVESTAV-IPNP.O.Box 17-74007000 Mexico CityMexico Instituto de Hidrología Universidad Tecnológica de la MixtecaOaxaca 69000 Huajuapan de LeónMexico National Collection of Microbial and Cellular Cultures CINVESTAV-IPNP.O.Box17-74007000 Mexico CityMexico Unidad de Secuenciación e Identificación de Polimorfismos Instituto Nacional de Medicina Genómica14610 Mexico CityMexico

Methane from enteric fermentation is the gas with the greatest environmental impact emitted by ***(Lv)addition to feedstocks could be a strategy to mitigate rumen methane emissions via decreasing the population of methanogenic archaea(MA).Thus,this paper provides the first overview of the effects of Lv supplementation,focusing on the inhibition of methane production,rumen microbiota,and ruminal *** indicated that Lv treatment had a strong anti-methanogenic effect on pure strains of ***,there are uncertainties from in vitro rumen fermentation trials with complex substrates and rumen ***-state fermentation(SSF)has emerged as a cost-effective option to produce *** this way,SSF of agricultural residues as an Lv-carrier supplement in sheep and goats demonstrated a consistent decrease in ruminal methane *** experimental evidence for in vitro conditions showed that Lv did not affect the volatile fatty acids(VFA).However,in vivo experiments demonstrated that the production of VFA was *** did not negatively affect the digestibility of dry matter during in vitro and in vivo methods,and there is even evidence that it can induce an increase in *** the rumen microbiota,populations of MA were reduced,and no differences were detected in alpha and beta diversity associated with Lv ***,some changes in the relative abundance of the microbiota were *** studies are recommended on:(i)Lv biodegradation products and stability,as well as its adsorption onto the solid matter in the rumen,to gain more insight on the“available”or effective Lv concentration;and(ii)to determine whether the effect of Lv on ruminal fermentation also depends on the feed composition and different ruminants.

关键词： Fermentation Lovastatin Methanogenesis Microbiota Rumen

Revisiting Stainless Steel as PWR Fuel Rod Cladding after Fukushima Daiichi Accident

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Journal of Energy and Power Engineering 2014年第6期8卷 973-980页

作者： alfredo Abe Claudia Giovedi daniel de Souza Gomes Antonio Teixeira e Silva Nuclear Engineering Center Nuclear and Energy Research Institute Brazilian Nuclear Energy Commission Sao Paulo05508-000 Brazil Laboratory for Developing of Nuclear Fuel and Instrumentation Navy Technological Center Sao Paulo 05508-000 Brazil

In the past, stainless steel was utilized as cladding in many PWRs （pressurized water reactors）, and its performance under irradiation was excellent. However, stainless steel was replaced by zirconium-based alloy as cladding material mainly due to its lower neutron absorption cross section. Now, stainless steel cladding appears as a possible solution for safety problems related to hydrogen production and explosion as occurred in Fukushima Daiichi accident. The aim of this paper is to discuss the steady-state irradiation performance using stainless steel as cladding. The results show that stainless steel rods display higher fuel temperatures and wider pellet-cladding gaps than Zircaloy rods and no gap closure. The thermal performance of the two rods is very similar and the neutron absorption penalty due to stainless steel use could be compensating by combining small increase in U-235 enrichment and pitch size changes.

关键词： Austenitic stainless steel cladding Zircaloy cladding PWR fuel rod steady-state fuel performance codes.

Green Hydrogen: Perspectives and Challenges in Using the Natural Gas Network in Ceará/Brazil

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Journal of Geoscience and Environment Protection 2024年第3期12卷 70-94页

作者： Francisco alfredo de Castro Mona Lisa Moura de Oliveira Lutero Carmo de Lima daniel Silveira Serra Science and Technology Center State University of Ceará Ceará Brazil Av. Dr. Silas Munguba 1700 Fortaleza-Ceará Brazil

Climate change, mainly caused by the use of non-renewable fuels, has raised global concerns and led to the search for less polluting energy sources, making hydrogen a promising energy alternative with the potential to contribute to changes in the energy mix of various countries through the use of technologies that enable its production and use with low or zero carbon emissions. In this context, Brazil has aroused great interest from other countries in exploring its renewable resources for the production of hydrogen (green hydrogen). In this sense, the use of natural gas pipelines and the use of hydrogen in mixtures with natural gas have become the subject of studies due to their economically viable alternative for the immediate use of this energy vector. However, there are still technical and regulatory challenges regarding the integration of hydrogen into the existing natural gas pipeline network. In this context, the present study aims to address the effects of hydrogen interaction with the structure of natural gas pipeline steel and the regulatory barriers to the use of this network for the transportation of green hydrogen, particularly in the state of Ceará/Brazil. After extensive analysis of literature and regulatory documents, it was concluded that: 1) Ceará/Brazil has strong potential to meet the demand for green hydrogen through the use of solar and wind energy sources;2) there is feasibility for the adaptation or conversion of natural gas infrastructure for the transportation of green hydrogen;3) discussions regarding the regulatory competence of green hydrogen transportation and distribution through the natural gas network in Brazil are still incipient;4) the current regulation of the natural gas industry can serve as a subsidy for the regulation of green hydrogen and natural gas transportation.

关键词： Decarbonization Natural Gas Green Hydrogen Pipelines

Synthesis, Characterization, Spectral Properties and Electrochemical of Compounds trans-[Ru(NH)₃L(bpa)]²⁺

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Open Journal of Inorganic Chemistry 2016年第2期6卷 135-145页

作者： Wagner Batista dos Santos Marcio Adriano Sousa Chagas K.M.D. de Sousa daniel Tizo Costa Luiz alfredo Pavanin Institute of Exact and Earth Sciences Federal University of Mato Grosso Cuiabá Brazil FESURV University of Rio Verde Rio Verde Brazil Chemical Institute Federal University of Uberlandia Uberlandia Brazil

n this work, we present synthesis of the compounds trans-[Ru(NH3)4L(bpa)]2+ where L is pyridine ligands: pyridine (py), isonicotinamide (isn), 4-acetylpyridine (4-acpy) and 4-picoline (4-pic) and 1,2-bis (4-pyridyl) ethane (bpa), their characterization by UV-visible spectroscopy and electrochemical properties. This series shows intense bands in the region between 400 and 515 nm, allocated bands charge transfer (MLCT), the influence of substituents on the pyridine ring (4-acpy and isn), and the interaction between the ligand and the metal, causing a second MLCT band, which is lighter and has more energy. The compound is characterized by spectroscopy by Fourier transform infrared spectroscopy (FTIR). The displacement observed in the symmetrical stretching of νs(CCN) group in the complex compared with the νs(CCN) group in the free ligand is indicative of coordination of the pyridine group to the Ruthenium (II) metallic center. The electrochemical data (cyclic voltammetry) show that reversibility criteria are well defined and formal Ef potential, indicating the influence of the pyridine ring substituent.

关键词： Ruthenium Pyridine Ligands MLCT Bands

Bilateral stones as a cause of acute renal failure in the emergency department

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World Journal of Emergency Medicine 2014年第1期5卷 67-71页

作者： Joaquín V.Alonso Pedro L.cachinero Fran R.Ubeda daniel J.L.Ruiz alfredo Blanco Department of Emergency and Critical care Medicine Hospital Valle de los Pedroches Department of Radiology Hospital Valle de los Pedroches Department of Urology Hospital Valle de los Pedroches

BACKGROUND: Acute renal failure(ARF) due to obstructive uropathy is a urological emergency. The standard radiological investigations in the emergency setting include X-ray, ultrasonography and computed tomography. But occasionally the cause of obstruction may be ***: We present a case of obstructive uropathy due to bilateral stones presenting as acute renal failure. The patient underwent successful shock wave lithotripsy(SWL) for dissolution of ***: The patient was successfully treated, and reported asymptomatic in a ***: Close collaboration between nephrological, urological, and radiological services is required.

关键词： Bilateral stones Acute renal failure Obstructive uropathy