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Developing an Advanced Prototype of the Acousto-Optical Radio-Wave spectrometer for studying star Formation in the Milky Way

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International Journal of Astronomy and Astrophysics 2014年第1期4卷 128-144页

作者： alexandre s. shcherbakov Abraham Luna National Institute for Astrophysics Optics & Electronics (INAOE) Puebla Mexico

The designed practically prototype of an advanced acousto-optical radio-wave spectrometer is presented in a view of its application to investigating the Milky Way star formation problems. The potential areas for observations of the cold interstellar medium, wherein such a spectrometer can be exploited successfully at different approximations, are: 1) comparison of the Milky Way case with extragalactic ones at scale of the complete galactic disk;2) global studies of the galactic spiral arms;and 3) characterization of specific regions like molecular clouds or star clusters. These aspects allow us to suggest that similar instrument will be really useful. The developed prototype of spectrometer is able to realize multi-channel wideband parallel spectrum analysis of very-high-frequency radio-wave signals with an improved resolution power exceeding 103. It includes the 1D-acousto-optic wide-aperture cell as the input device for real-time scale data processing. Here, the current state of developing this acousto-optical spectrometer in frames of the astrophysical instrumentation is briefly discussed, and the data obtained experimentally with a tellurium dioxide crystalline acousto-optical cell are presented. Then, we describe a new technique for more precise spectrum analysis within an algorithm of the collinear wave heterodyning. It implies a two-stage integrated processing, namely, the wave heterodyning of a signal in an acoustically square-law nonlinear medium and then the optical processing in the same solid-state cell. Technical advantage of this approach lies in providing a direct multi-channel parallel processing of ultra-high-frequency radio-wave signals with the resolution power exceeding 104. This algorithm can be realized on a basis of exploiting a large-aperture effective acousto-optical cell, which operates in the Bragg regime and performs the ultra-high-frequency co-directional collinear acoustic wave heterodyning. The general concept and basic conclusions her

关键词： star Formation Astronomical Instrumentation Cold Interstellar Medium Acousto-Optical spectrum Analysis Frequency Bandwidth and Resolution Wide-Aperture Acousto-Optical Cell Collinear Wave Heterodyning

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Resistance of Two Maize Landraces in Breeding stage to the Attack of <i>sitophilus zeamais</i>

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American Journal of Plant sciences 2014年第20期5卷 2929-2934页

作者： Rejane Teixeira do Nascimento Bruno Ettore Pavan Luciana Barboza silva gabriel dos santos Carvalho alexandre Faria da silva Kellen Maggioni graduate Program in Agronomy-Crop science Federal University of Piauí Bom Jesus Brazil College of Engineering of Ilha solteira—DFTAsE—UNEsP S&atildeo Paulo Brasil

This study aimed to assess the resistance of grain from two varieties of maize landraces in initial breeding in Bom Jesus-PI, with respect to s. zeamais attack. seeds of two maize landraces were used: purple straw maize from two different origins (são Paulo (sP) and Espírito santo (Es)) and Peruvian purple maize. The experimental design was completely randomized with four replications. The data for each response variable were subjected to analysis of variance, applying the F-test (p ≤ 0.05), and when significant differences were found, there was a comparison of means by Tukey test (p ≤ 0.05). The statistical analyses were performed using the software sAs®. In a free-choice test and bioassay for evaluating the nutritional index (no choice test), maize varieties differed significantly by Tukey test and the cultivar sP was considered resistant, while the cultivars purple and Es were considered susceptible.

关键词： selection genetic Variability susceptibility

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NiWO4 powders prepared via polymeric precursor method for application as ceramic luminescent pigments

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Journal of Advanced Ceramics 2020年第1期9卷 55-63页

作者： Naiara A.LIMA Lorena D.s.ALENCAR Máximo sIU-LI Carlos A.C.FEITOsA alexandre MEsQUITA Jean-Claude M’PEKO Maria I.B.BERNARDI Instituto de Física de sao Carlos Universidade de Sao Paulo13560-970 Sao CarlosSPBrazil Instituto Federal de Mato grosso do sul IFMS79200-000 AquidauanaMSBrazil Departamento de Física Centro de Ciências Exatas e TecnologiaUniversidade Federal do MaranhaoUFMA65080-805Sao LuisMABrazil Instituto de geociências e Ciências Exatas Departamento de FísicaUniversidade Estadual Paulista13506-900Rio ClaroSPBrazil

Ni WO4 was prepared using the polymeric precursor method and studied in terms of physical and chemical properties to verify its stability for industrial applications as *** characterization was accomplished using thermal analyses,X-ray diffraction(XRD),scanning electron microscopy(sEM),photoluminescence(PL)and UV–Vis spectroscopies,colorimetric coordinates,and Raman *** the temperature,successive exothermic reactions were observed and they are related with thermal decomposition of the organic *** stability was reached at^700℃.The material is verified to become completely free of second phase at^800℃.The end Ni WO4 powders showed an intense charge transfer(CT)-related tail centered in the ultraviolet region,resulting in a yellow *** addition,the powders exhibited broad excitation band and broad deep blue–green emission band,which were enhanced with increasing powders’crystallinity.

关键词： nickel tungstate yellow pigment colorimetric coordinate optical property structural characterization

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Natural Regeneration in Tropical secondary Forest in southern Amazonia, Brazil

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Open Journal of Forestry 2014年第2期4卷 151-160页

作者： alexandre Ebert Leandro Ribeiro Teixeira Adriana Zanirato Contini da silva Reginaldo Brito da Costa Faculty of Forestry Engineering Federal University of Mato Grosso Cuiabá Brazil

The study aimed to establish floral composition, diversity levels, category size, phytosociological structure, commercial use and ecological group of species present in the regeneration of open ombrophile forest in southern Amazon, Brazil. Data were collected at s?o Nicolau farm, in the municipality of Cotrigua?u, northwest of Mato grosso state, coordinates 51°9'19.5"s and 58°14'53"W. One hundred plots of 10 × 10 m were allocated. All individuals between 29.9 and 59.9 cm had circumference at breast height (CAP) measure, with sub-plots of 5 × 5 m which were measured in all subjects between 1:50 m in height 29.9 cm CAP and sub-plots of 2 × 2 m for individuals between 0.30 to 1.5 m tall. The information obtained in the field were processed in excel spreadsheet. The results showed the occurrence of 610 individuals belonging to 82 species, 34 plant families, with a diversity index of shannon & Weaver’s 2.77. The index of value of importance showed species Protium robustum, Maquira calophilla and Inga fagifolium with greater ecological importance in fitocenose. The higher values for Natural Regeneration were the species Protium robustum, Maquira calophilla and Inga fagifolium with 16.42, 8.03 and 7.76 respectively.

关键词： Vertical structure Ecological Analysis Forest Management

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Transcatheter aortic valve replacement in elderly patients

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Journal of geriatric Cardiology 2012年第2期9卷 78-82页

作者： Dimytri siqueira alexandre Abizaid Magaly Arrais J. Eduardo sousa institute Dante Pazzanese of Cardiology Av. Dr Dante Pazzanese 500 Ibirapuera S~o Paulo CEP 04012080 Brazil Heart Hospital Rua Desembargador Eliseu Guilherme 147 Paralso Sao Paulo CEP 040004030 Brazil

Aortic stenosis is the most common native valve disease, affecting up to 5% of the elderly population. surgical aortic valve replacement reduces symptoms and improves survival, and is the definitive therapy in patients with symptomatic severe aortic stenosis. However, despite the good results of classic surgery, risk is markedly increased in elderly patients with co-morbidities. Transcatheter aortic valve replacement （TAVR） allows implantation of a prosthetic heart valve within the diseased native aortic valve without the need for open heart surgery and cardiopulmonary bypass, offering a new therapeutic option to elderly patients considered at high surgical risk or with contraindications to surgery. To date, several multicenter registries and a randomized trial have confirmed the safety and efficacy of TAVR in those patients. In this chapter, we review the background and clinical applications of TAVR in elderly patients.

关键词： Aortic stenosis Elderly patients Transcatheter aortic valve replacement Percutaneous valve therapies

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Current aspects of therapeutic reduction mammaplasty for immediate early breast cancer management: An update

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World Journal of Clinical Oncology 2014年第1期5卷 1-18页

作者： alexandre Mendona Munhoz Eduardo Montag Rolf gemperli Division of Plastic surgery Hospital Sírio Libanês Sao Paulo 01239-040 Brazil Breast Reconstruction group University of Sao Paulo School of Medicine Sao Paulo 01239-040 Brazil Department of Plastic surgery University of Sao Paulo School of Medicine Sao Paulo 01239-040 Brazil

Breast-conservation surgery(BCs) is established as a safe surgical treatment for most patients with early breast cancer. Recently, advances in oncoplastic techniques are capable of preserving the breast form and quality of life. Although most BCs defects can be managed with primary closure, the aesthetic outcome may be unpredictable. Among technical options, therapeutic reduction mammaplasty(TRM) remains a useful procedure since the BCs defect can be repaired and the preoperative appearance can be improved, resulting in more proportional breasts. As a consequence of rich breast tissue vascularization, the greater part of reduction techniques have based their planning on preserving the pedicle of the nipple-areola complex after tumor removal. Reliable circulation and improvement of a conical shape to the breast are commonly described in TRM reconstructions. With an immediate approach, the surgical process is smooth since both procedures can be carried out in one operative setting. Additionally,it permits wider excision of the tumor, with a superior mean volume of the specimen and potentially reduces the incidence of margin involvement. Regardless of the fact that there is no consensus concerning the best TRM technique, the criteria is determined by the surgeon's experience, the extent/location of glandular tissue resection and the size of the defect in relation to the size of the remaining breast. The main advantages of the technique utilized should include reproducibility, low interference with the oncological treatment and long-term results. The success of the procedure depends on patient selection, coordinated planning and careful intra-operative management.

关键词： Breast reconstruction Conservative breast surgery Partial mastectomy Oncoplastic Reduction mammaplasty Outcome Complications

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Epidemiology of inflammatory bowel diseases in the state of Rio grande do sul,Brazil

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World Journal of gastroenterology 2022年第30期28卷 4174-4181页

作者： Ornella sari Cassol gilmara Pandolfo Zabot Rogerio saad-Hossne alexandre Padoin Department of Coloproctology IMED Medical SchoolPasso Fundo 99010260RSBrazil graduate Program in Medicine and Health sciences Pontifícia Universidade Católica do Rio Grande do Sul(PUCRS)Porto Alegre 90610001RSBrazil Department of Coloproctology Coloprocto Canoas ClinicCanoas 92310205RSBrazil Department of Coloproctology Hospital Moinhos de Vento(HMV)Porto Alegre 90035000RSBrazil Department of surgery and Orthopaedics Universidade Estadual Paulista(UNESP)Botucatu 18618687SPBrazil

BACKgROUND This is the first study on the epidemiology of inflammatory bowel diseases(IBDs)in Rio grande do sul(Rs),the southernmost state of Brazil with the country’s fifth largest ***’s disease(CD)and ulcerative colitis(UC)are collectively termed *** have high incidence and prevalence rates in highincome countries,although in recent years there has been a change in the classic geographical distribution of IBDs,with growing rates in traditionally lowincidence *** To estimate the incidence and prevalence of IBDs in the Rs state,Brazil,between 2014 and *** This is a cross-sectional descriptive observational *** with IBD who had initiated treatment and met the inclusion criteria of the Rs state free drug distribution program were *** were obtained from registration or renewal records of the Rs state specialty *** male,female,and total populations were estimated according to mid-year data from the Brazilian Institute of geography and statistics,which served as a reference for calculating the incidence and prevalence rates of IBDs during the study *** were described using mean,standard deviation,and *** We included 1082 patients with IBD,of whom 57.5%were female and 42.5% were *** with CD accounted for 72.45% of the sample,and those with UC accounted for 27.54%.IBD prevalence during the study period was 9.51 per 100000 population,of which 6.89 corresponded to people with CD and 2.62,to people with *** rates per 100000 population/year were 2.54 in 2014,2.61 in 2015,1.91 in 2016,0.80 in 2017,0.83 in 2018,and 0.96 in *** mean IBD incidence rate per 100000 population was 1.61,of which 1.17 corresponded to CD and 0.44,to *** mean age was 41 years,and patients were mostly aged 30-40 *** by region was higher in the state capital metropolitan area:12.69 per 100000 *** Our results demonstrated an IBD prevalence of 9.51% and incidence of

关键词： Inflammatory bowel diseases Crohn’s disease Ulcerative colitis Epidemiology Incidence Prevalence

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structure and collaboration relationship analysis in a scientific collaboration network

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Chinese science Bulletin 2011年第34期56卷 3702-3706页

作者： HUI Zi CAI Xu gRENECHE Jean-Marc WANg Qiuping alexandre LUNAM Universite ISMANS 44 Ave. Bartholdi 72000 Le Mans France Complexity science Center Institute of Particle Physics Central China Normal University Wuhan 430079 China LUNAM Universite Universite du Maine LPEC UMR CNRS 6087 72085 Le Mans France

We construct a weighted network of scientific collaboration in computational geometry and study the statistical properties of the network. In addition, we introduce a parameter called the collaboration relationship parameter to measure the collaboration between scientists. The collaboration relationship parameter of two scientists depends not only on the connection weights between the nodes, but also on the network's structure. The stability of the network's structure in terms of different edge removal strategies is also studied. According to the parameter, we find that a community structure exists in this type of network.

关键词：合作网络社会结构科学家协作关系合作关系计算几何统计特性参数调用

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The uncertainty measure for q-exponential distribution function

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Chinese science Bulletin 2013年第13期58卷 1524-1528页

作者： OU CongJie EL KAABOUCHI Aziz WANg QiuPing alexandre CHEN JinCan College of Information science and Engineering Huaqiao University Institut supérieur des Matériaux et Mécaniques Avancés du Mans 44Avenue F.A. Bartholdi72000 Le MansFrance Department of Physics Xiamen University

Based on the q-exponential distribution which has been observed in more and more physical systems, the uncertainty measure of such an abnormal distribution can be derived by employing a variational relationship which can be traced from the first and second thermodynamic laws. The uncertainty measure obtained here can be considered as the entropic form for the abnormal physical systems having observable q-exponential distribution. This entropy will tend to the Boltzmann-gibbs entropy when the nonextensive parameter tends to unity. It is very important to find that this entropic form is always concave and the systemic entropy is maximizable.

关键词：不确定性度量分布函数不确定性测度指数分布物理系统异常分布热力学定律吉布斯

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Experimental Evaluation of Thermal Conductivity and Other Thermophysical Properties of Nanofluids Based on Functionalized (-OH) Mwcnt Nanoparticles Dispersed in Distilled Water

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Advances in Nanoparticles 2023年第1期12卷 32-52页

作者： alexandre Melo Oliveira Amir Zacarias Mesquita João gabriel de Oliveira Marques Enio Pedone Bandarra filho Daniel Artur Pinheiro Palma Federal Institute of sã o Paulo (IFSP) S&atildeo Carlos Brazil Nuclear Technology Development Center (CDTN) Belo Horizonte Brazil Federal University of Uberlandia (UFU) Uberlandia Brazil Brazilian Nuclear Energy Comission Rio de Janeiro Brazil

A possible way to increase thermal conductivity of working fluids, while keeping pressure drop at acceptable levels, is through nanofluids. Nanofluids are nano-sized particles dispersed in conventional working fluids. A great number of materials have potential to be used in nanoparticles production and then in nanofluids;one of them is Multi-Walled Carbon Nano Tubes (MWCNT). They have thermal conductivity around 3000 W/mK while other materials used as nanoparticles like CuO have thermal conductivity of 76.5 W/mK. Due to this fact, MWCNT nanoparticles have potential to be used in nanofluids production, aiming to increase heat transfer rate in energy systems. In this context, the main goal of this paper is to evaluate from the synthesis to the experimental measurement of thermal conductivity of nanofluid samples based on functionalized (-OH) MWCNT nanoparticles. They will be analyzed nanoparticles with different functionalization degrees (4% wt, 6% wt, and 9% wt). In addition, it will be quantified other thermophysical properties (dynamic viscosity, specific heat and specific mass) of the synthetized nanofluids. so, the present work can contribute with experimental data that will help researches in the study and development of MWCNT nanofluids. According to the results, the maximum increment obtained in thermal conductivity was 10.65% in relation to the base fluid (water).

关键词： Nanofluids Multi-Walled Carbon Nano Tubes (MWCNT) Functionalization Degree Thermal Conductivity Thermophysical Properties

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