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Journal of Rare Earths 2022年第2期40卷 260-267,I0003页

作者： alexandre candido teixeira Ivan Guide Nunes Silva Alysson Ferreira Morais Danilo Mustafa Physics Institute.University of Sao Paulo 05508-090Sao PauloSPBrazil

While the versatile composition of layered double hydroxides(LDHs)allows the introduction of almost any polyvalent cation in their structure,the exchangeable negatively charged ions intercalated between the plates increase their vast range of functionalities.Here we report on the preparation and optical properties of pillared Eu^(3+)-substituted ZnAl LDHs intercalated by aliphatic dicarboxylates:-OOC-(CH_(2))_(n-2)-COO-.The basal distance in these materials is dependent on the size and packing of the intercalated anions.By varying the number(n)of carbon atoms in the aliphatic chain from 2 to 12,the interlayer gallery of these ZnAlEu LDHs is considerably expanded from 0.9 to 2.1 nm.In the interlayer gallery,the aliphatic dicarboxylates form a monolayer,with the aliphatic chain inclined by an angleα≈63°with the hydroxide layers.The carbon atom in the COO-group is 0.43 nm far from the metal plane,showing that these carboxylates are not grafted in the brucite-like layers.These LDHs are thermally stable up to around 150℃,after which dehydroxylation of the hydroxide layers is observed.The Judd-Ofelt intensity parameters were obtained and compared to the Eu^(3+)-containing complexes with the same ligand series indicating a more symmetrical and less polarizable chemical environment around the rare earth ion.

关键词： Europium Layered double hydroxides Carboxylate ligands Luminescence Rare earths

Natural Mg silicates with different structures and morphologies: Reaction with K to produce K2MgSiO4 catalyst for biodiesel production

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 46-54页

作者： Fabiane Carvalho Ballotin Mayra Nascimento Sara Silveira Vieira alexandre Carvalho Bertoli Ottávio Carmignano Ana Paula de Carvalho teixeira Rochel Montero Lago Departamento de Química Universidade Federal de Minas GeraisBelo HorizonteBrasil Doutorado Inovação/Mineradora Pedras Congonhas Universidade Federal de Minas Gerais31270-901 Belo Horizonte-MGBrazil

In this work, different magnesium silicate mineral samples based on antigorite, lizardite, chrysotile(which have the same general formula Mg3Si2O5(OH)4), and talc(Mg3Si4O10(OH)2) were reacted with KOH to prepare catalysts for biodiesel production. Simple impregnation with 20 wt% K and treatment at 700–900°C led to a solid-state reaction to mainly form the K2MgSiO4 phase in all samples. These results indicate that the K ion can diffuse into the different Mg silicate structures and textures, likely through intercalation in the interlayer space of the different mineral samples followed by dehydroxylation and K2MgSiO4 formation. All the materials showed catalytic activity for the transesterification of soybean oil(1:6 of oil : methanol molar ratio, 5 wt% of catalyst, 60°C). However, the best results were obtained for the antigorite and chrysotile precursors, which are discussed in terms of mineral structure and the more efficient formation of the active phase K2MgSiO4.

关键词： silicate serpentinite lizardite antigorite talc chrysotile biodiesel

In Vitro Evaluation of Two Tissue Substitutes for Gingival Augmentation

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Journal of Biomaterials and Nanobiotechnology 2023年第2期14卷 23-34页

作者： Tulio Cardoso dos Santos Carlos Nelson Elias alexandre Barboza Lemos Andresa Borges Soares André Antonio Pelegrine Lucas Novaes teixeira Elizabeth Ferreira Martinez Division of Oral Implantology Faculdade S&#227o Leopoldo Mandic Campinas SP Brazil Department of Materials Science Military Institute of Engineering (IME) Rio de Janeiro RJ Brazil Division of Oral Pathology Faculdade S&#227o Leopoldo Mandic Campinas SP Brazil Division of Cell Biology Faculdade S&#227o Leopoldo Mandic Campinas SP Brazil

Three-dimensional collagen matrices of porcine origin are being used as substitutes for soft tissue grafts in periodontal plastic surgery in search of aesthetic and natural results. This in vitro study aimed to compare Fibro-Gide® (GeistlichBiomaterials) and Mucoderm® (BotissBiomaterials) matrices during the initial phase of soft tissue formation. For this purpose, samples of 5 × 5 mm were obtained, and then human fibroblasts were plated on them. After 24, 48 and 72 h, cell viability was assessed using an MTT assay, and the secretion of type I collagen, MMP-2, TIMP-1 and TIMP-2 was analyzed by ELISA immunoassay. The control group (C) consisted of cells plated on polystyrene without the matrices. The morphology of the surfaces was also examined using scanning electron microscopy (SEM), as was the average roughness (Ra) of the samples by a profilometer. Topographic analysis revealed that roughness was significantly higher on Mucoderm® than on Fibro-Gide® (p 0.05). The synthesis of type I collagen, MMP-2 and TIMP-1 were significantly higher from cells plated on Fibro-Gide® than on Mucoderm®, in all time points (p ® than on Mucoderm® (p ® induced an increase in type I collagen, MMP-2 and TIMP-1 and TIMP-2.

关键词： Collagen Matrices Gingival Recession Periodontal Regeneration Matrix Metalloproteinases

Pain inhibition through transplantation of fetal neuronal progenitors into the injured spinal cord in rats

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Neural Regeneration Research 2019年第11期14卷 2011-2019页

作者： Chary M. Batista Eric D. Mariano Camila S. Dale alexandre F. Cristante Luiz R. Britto Jose P. Otoch Manoel J. teixeira Matthias Morgalla Guilherme Lepski Department of Neurology School of MedicineUniversity of Sao PauloSao PauloBrazil Department of Anatomy Institute of Biomedical ScienceUniversity of Sao PauloSao PauloBrazil Department of Orthopedic and Traumatology School of MedicineUniversity of Sao PauloSao PauloBrazil Department of Physiology and Biophysics Institute of Biomedical ScienceUniversity of Sao PauloSao PauloBrazil Department of Surgery School of MedicineUniversity of Sao PauloSao PauloBrazil Department of Neurosurgery Eberhard-Karls UniversityTuebingenGermany Department of Psychiatry School of MedicineUniversity of Sao PauloSao PauloBrazil

Neuropathic pain after spinal cord injury(SCI) is a complex condition that responds poorly to usual treatments. Cell transplantation represents a promising therapy;nevertheless, the ideal cell type in terms of neurogenic potential and effectiveness against pain remains largely controversial. Here, we evaluated the ability of fetal neural stem cells(fNSC) to relieve chronic pain and, secondarily, their effects on motor recovery. Adult Wistar rats with traumatic SCI were treated, 10 days after injury, with intra-spinal injections of culture medium(sham) or fNSCs extracted from telencephalic vesicles(TV group) or the ventral medulla(VM group) of E/14 embryos. Sensory(von Frey filaments and hot plate) and motor(the Basso, Beattie,Bresnahan locomotor rating scale and inclined plane test) assessments were performed during 8 weeks. Thereafter, spinal cords were processed for immunofluorescence and transplanted cells were quantified by stereology. The results showed improvement of thermal hyperalgesia in the TV and VM groups at 4 and 5 weeks after transplantation, respectively. Moreover, mechanical allodynia improved in both the TV and VM groups at 8 weeks. No significant motor recovery was observed in the TV or VM groups compared with sham. Stereological analyses showed that ~70% of TV and VM cells differentiated into NeuN+ neurons,with a high proportion of enkephalinergic and GABAergic cells in the TV group and enkephalinergic and serotoninergic cells in the VM group. Our study suggests that neuronal precursors from TV and VM, once implanted into the injured spinal cord, maturate into different neuronal subtypes, mainly GABAergic, serotoninergic, and enkephalinergic, and all subtypes alleviate pain, despite no significant motor recovery. The study was approved by the Animal Ethics Committee of the Medical School of the University of S?o Paulo(protocol number 033/14) on March 4, 2016.

关键词： spinal cord injuries chronic pain neural stem cells cell transplantation neuronal differentiation GABAergic neuron serotoninergic neuron enkephalinergic neuron

Acute cholestatic hepatitis caused by amoxicillin/ clavulanate

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World Journal of Gastroenterology 2013年第46期19卷 8789-8792页

作者： Daniel Oliveira Beraldo Joanderson Fernandes Melo alexandre Vidal Bonfim Andrei Alkmim teixeira Ricardo Alkmim teixeira André Loyola Duarte Department of Internal Medicine Hospital Renascentista Escola Paulista de Medicina-UNIFESP Nephrology Department Escola Paulista de Medicina-UNIFESP Cardiology Department Cardiology Department Instituto do Cora o-FMUSP Pathology Department Hospital A.C.CamargoSo Paulo

Amoxicillin/clavulanate is a synthetic penicillin that is currently commonly used,especially for the treatment of respiratory and cutaneous infections.In general,it is a well-tolerated oral antibiotic.However,amoxicillin/clavulanate can cause adverse effects,mainly cutaneous,gastrointestinal,hepatic and hematologic,in some cases.Presented here is a case report of a 63-yearold male patient who developed cholestatic hepatitis after recent use of amoxicillin/clavulanate.After 6 wk of prolonged use of the drug,he began to show signs of cholestatic icterus and developed severe hyperbilirubinemia(total bilirubin>300 mg/L).Diagnostic investigation was conducted by ultrasonography of the upper abdomen,serum tests for infection history,laboratory screening of autoimmune diseases,nuclear magnetic resonance(NMR)of the abdomen with bile duct-NMR and transcutaneous liver biopsy guided by ultrasound.The duration of disease was approximately 4 mo,with complete resolution of symptoms and laboratory changes at the end of that time period.Specific treatment was not instituted,only a combination of anti-emetic(metoclopramide)and cholestyramine for pruritus.

关键词： Hepatology Hepatitis Amoxicillin/Clavula-nate Drug reactions Hyperbilirubinemia

Synthesis and structure of a praseodymium (Ⅲ) complex with carboxylate ligand：A thermal and spectroscopic study

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Journal of Rare Earths 2018年第10期36卷 1090-1097页

作者： Kátia Veronica Tenório José Augusto teixeira Leandro Moreira de Campos Pinto Flávio Júnior Caires Oswaldo Treu-Filho Fáhio Alencar dos Santos Tiago André Denck Colman alexandre Cuin Cláudio Teodoro de Carvalho Federal University of Grande Dourados CP 364 79804-970 Dourados MS Brazil Institute of Chemistry State University of Sao Paulo 14.801-970 Araraquara SP Brazil Chemistry Institute Federal University of Mato Grosso do Sul 79074-460 Campo Grande MS Brazil Chemistry Department State University of Sao Paulo 17033-360 Bauru SR Brazil Federal University of Juiz de Fore 36036-330 Juiz de Fora MG Brazil

One Pr（Ⅲ） lanthanide ion complex was initially synthesized and characterized by TGA-DSC in air atmosphere, as well as characterized by CHN elemental analysis, defining the stoichiometric ratio as Pr（DMBz）3. The gaseous products evolved during the thermal decomposition were also monitored in N2 atmosphere employing TGA/FT-IR system. A crystal structure is obtained by state-of-the-art powder X-rays diffraction methods measured in conventional laboratory equipment and refined by the Rietveld method, which defined it as a monoclinic system of the space group P21/C with a polymeric crystal structure, [Pr（DMBZ）3]n. FT-IR theoretical spectrum and time-dependent density functional theory（TD-DFT） were calculated from TGA-DSC and crystalline system data. The experimental and theoretical FT-IR spectra present a high correlation degree when the main stretching bands are compared, while the energy transfer（HOMO - LUMO） in their neighborhoods suggests the main contributions of the light-emitting states.

关键词： Complex Thermal analysis Powder diffraction state-of-art Polymeric structure Theoretical calculation Rare earths

Feasibility Study for Power Generation during Peak Hours with a Hybrid System in a Recycled Paper Mill

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Computational Water, Energy, and Environmental Engineering 2013年第2期2卷 43-53页

作者： Adriano Beluco Clodomiro P.Colvara Luis E.teixeira alexandre Beluco Universidade Ritter dos Reis Porto AlegreBrazil Genesys Participacoes Ltd. Porto AlegreBrazil Institution Pesquisas Hidráulicas Universidade Federal do Rio Grande do SulPorto AlegreBrazil

The differential pricing for peak hours encourages industrial consumers to look for independent power supplies for the period from 19 to 22 hours. This paper presents a study to identify the optimal solution for a recycled paper mill that also intends to work in that period. The factory is located in Rio Grande do Sul, in southern Brazil, and considers the use of a diesel gen set, a micro hydro power plant and possibly PV modules. Two micro hydro power plants were considered in the study, an old plant to be renewed and another to be fully implemented. The software Homer was used as a tool to determine the most feasible combination of components considered in the study. The sale of surplus power to the energy system appears as a key to viability of alternatives that are not based solely on diesel generators. The optimal solution consists of a combination of diesel generators and micro hydro power plant, in one case, and only on hydroelectric power plant in another, with a significant penetration of PV modules if its cost is reduced to 12% of the current price, selling an amount of energy equal to that which is bought. The annual water availability in one of the sites requires diesel supplement, while the other, more abundant, this supplement is not necessary.

关键词： Hybrid Energy Systems Micro Hydro Power PV Modules Energetic Complementarity Feasibility Study Computational Simulation Software Homer

Age and Calcium Sources in Laying Hen Feed Affect Calcium Digestibility

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Open Journal of Animal Sciences 2021年第3期11卷 501-513页

作者： Thiago Ferreira Diana Arele Arlindo Calderano Fernando de Castro Tavernari Horácio Santiago Rostagno alexandre de Oliveira teixeira Luiz Fernando teixeira Albino Department of Animal Sciences Universidade Federal de Vi&#231osa Vi&#231osa MG Brazil Embrapa Suínos e aves Concórdia SC Brazil Department of Animal Sciences Universidade Federal de S&#227o Jo&#227o del-Rei S&#227o Jo&#227o del-Rei MG Brazil

The apparent calcium (Ca) digestibility coefficient (ADC) and true digestibility coefficient (TDC) of different inorganic calcium sources were determined in laying hens of different ages. Three Ca digestibility tests were carried out, each assessing 240 Lohmann Brown lineage laying hens distributed in a completely randomized design. Nine dietary treatments were arranged in a 3 × 3 factorial design consisting of three ages (40, 50 and 70 weeks) × three Ca (dicalcium phosphate (DCP) sources, fine (FL) and coarse (CL)) limestone, comprising eight replicates per treatment of six birds per experimental unit. Regarding the DCP, the ADC was higher (P as 0.889, 0.613 and 0.712, respectively. No effect (P > 0.05) of age on the ADC was noted for either FL or CL. Comparing Ca sources, DCP exhibited a higher (P 0.05). Endogenous loss values of 790, 860 and 930 mg·kg

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

Monte Carlo Simulations for a Preliminary Design of TRIGA IPR-R1 PGAA Facility

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Journal of Chemistry and Chemical Engineering 2016年第6期10卷 256-270页

作者： Bruno teixeira Guerra alexandre Soares Leal Claubia Pereira Maria Angela de Barros Correia Menezes DEN (Departamento de Engenharia Nuclear) UFMG (Universidade Federal de Minas Gerais) Av. Antonio Carlos 6627 Campus Pampulha CEP 31270 901 Belo Horizonte Minas Gerais Brazil CDTN (Nuclear Technology Development Center) CNEN (Brazilian Commission for Nuclear Energy) Av. Antonio Carlos 6627 Campus UFMG CEP 31270 901 Belo Horizonte Minas Gerais Brazil