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The peptide fraction of Bothrops jararaca snake venom induces toxicological effects on the male reproductive system after local envenomation in mice

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BIOCELL 2023年第2期47卷 289-295页

作者： carlos alberto-silva ANA CAROLINA DE ARAUJO RODRIGO SIMÃO BONFIM JOYCE MEIRE GILIO Natural and Humanities Sciences Center Experimental Morphophysiology LaboratoryFederal University of ABC(UFABC)São Bernardo do Campo09606-070Brazil Departamento de Biofísica Universidade Federal de São PauloSão Paulo04023-062Brazil

Bothrops envenomation is complex and provokes prominent local tissue damage and systemic disturbances,but little is known about their effects on the male reproductive *** intratesticular injection,the bioactive peptide fraction(Bj-PF)obtained from Bothrops jararaca snake venom changes the structure of different stages of the seminiferous epithelium cycle in adult *** the first time,we investigated whether local envenomation of Bj-PF induces toxicological effects on the male reproductive system,particularly on the seminiferous epithelium and Sertoli *** adult mice were treated with 0.24 ***^(-1) by intramuscular(i.m.)injection for 24 *** testes samples were collected for morphological and morphometric *** toxicological effects of Bj-PF were also analyzed on mitochondrial metabolism and nitrite(NO2)production in 15P-1 Sertoli cell ***-PF changed the structure and function of the seminiferous epithelium,particularly the disruption of the epithelium and the presence of degenerated germ cells in the adluminal compartment,but there were no alterations in the basal ***-PF increased the thickness of the seminiferous epithelium and decreased the lumen diameter of the *** histological assessment of the degree of tubule degeneration revealed that Bj-PF also increased the number of hypospermatogenic tubules compared to ***-PF reduced NO2 levels in 15P-1 Sertoli cells without changing the mitochondrial ***,the fact that Bj-PF alters the structure and function of the seminiferous epithelium suggests that bioactive peptides found in *** snake venom can have toxicological effects on the reproductive systems of affected male mice,providing new insight into the biological characteristics of snake venom and therapeutic strategies for envenomation inflammation.

关键词： Snake venom Bothrops jararaca Reproductive toxicology Seminiferous epithelium

Preparation of High Purity Neodymium Oxide from Brazilian Monazite by Ion Exchange

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Journal of Energy and Power Engineering 2015年第7期9卷 616-621页

作者： carlos alberto da silva Queiroz Jose Antonio Seneda Walter dos Reis Pedreira Filho IPEN/CNEN-SP (Instituto de Pesquisas Energeticas e Nucleares/Comissao Nacional de Eneergia Nuclear-Sao Paulo) Cidade Universitaria Sao Paulo 05508-000. Brazil Fundacao Jorge Duprat Figueiredo de Seguranca e Medicina do Trabalho-FUNDACENTRO Sao Paulo 05409-002 Brazil

A simple and economical chemical process for obtaining high purity neodymium oxide is discussed. The raw material in the form of RE （rare earth） carbonates is produced industrially in Brazil from monazite. Using this concentrate as the feed material, ion exchange with a strong cationic resin, commonly used for water treatment, and without the use of retention ions was used for the fractionating of the REE （rare earth elements）. The eluent was ammonium salt of EDTA （ethylenediaminetetraacetic acid） at pH 4.0. The complex of EDTA-neodymium was transformed into neodymium oxides via oxalate precipitation. We produced 99.9% pure Nd203 in yields greater than or equal to 80%. Molecular absorption spectrophotometry was used to monitor the neodymium content during the process and sector field inductively coupled plasma mass spectrometry was used to certify the purity of the neodymium oxides. The typical neodymium oxides obtained contained the followings contaminants in micrograms per gram： Sc （4.09）; Y （0.39）; La （0.78）; Ce （5.62）; Pr （4.56）; Sm （11.10）; Eu （1.10）; Gd （14.30）; Tb （29.3）; Dy （4.15）; Ho （8.39）; Er （13.80）; Tm （0.23）; Yb （2.29）; Lu （0.39）. High purity neodymium oxides obtained from this procedure replaced the imported product used in research and development work on rare earth at IPEN/CNEN-SP （Instituto de Pesquisas Energeticas e Nucleares/Comissfio Nacional de Eneergia Nuclear-Sao Paulo）.

关键词： Neodymium oxide elemental rare earths separation rare earths.

Fatigue Strength Evaluation of Resin-Injected Bolted Connections Using Statistical Analysis

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Engineering 2017年第6期3卷 795-805页

作者： Jose Antonio Fonseca de Oliveira Correia Bruno Alexandre silva Pedrosa Patricia Cordeiro Raposo Abilio Manuel Pinho De Jesus Helena Maria dos Santos Gervisio Grzegorz Stanislaw Lesiukc carlos alberto da silva Rebelo Rui Artur Bartolo Calcada Luis alberto Proenca Simoes da silva Faculty of Engineering University of Porto Porto 4200-465 Portugal Institute for Sustainability and Innovation in Structural Engineering (ISISE) Department of Civil Engineering University of Coimbra Coimbra 3030-788 Portugal Department of Mechanics Materials Science and Engineering Faculty of Mechanical Engineering Wroclaw University of Technology Wroctaw 50-370 Poland

Different strategies can be used to perform reparations and reinforcements of ancient bolted and riveted metallic bridges. As the riveting process is not currently a common practice, it requires proper equipment and skilled workers. Another solution is the use of welding. However, the weldability of old steels is poor. Bolts are very attractive alternative solutions, and are most commonly used to repair old metallic bridges. Fitted bolts are expensive solutions; the alternative is the use of resin-injected bolts. The behavior of bolted joints with preloaded resin-injected bolts has been studied using quasi-static and creep tests; however, few studies on the slip and fatigue behavior of these joints can be found in the literature. This paper presents an overview of a few experimental programs that were carried out by several authors aiming at evaluating the fatigue behavior of single and double shear resin-injected bolted connections. A comparison between the experimental data of joints with preloaded standard bolts and preloaded resin- injected bolts shows a fatigue strength reduction in the latter. Since Eurocode 3 （EC3） suggests the same fatigue strength curve for joints made of resin-injected bolts and standard bolts, this may raise some con- cerns. Furthermore, research on the feasibility of using both bonded and bolted connections is shown. This last study was performed with high-strength low-alloy structural steel plates and an acrylic struc- tural adhesive for metal bonding. For both case studies, a statistical analysis is performed on fatigue experimental data using linearized boundaries and the Castillo and Fernandez-Canteli model. Fatigue design curves are proposed and compared with the design suggestions of several European and North American standards,

关键词： Fatigue Connections Structural reinforcements Structural adhesives S-N curves Resin-injected bolts

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Design Optimization and Weight Reduction of 500 mL CSD PET Bottle through FEM Simulations

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材料科学与工程（中英文B版） 2011年第7期1卷 947-959页

作者： carlos alberto silva De Miranda Jairo Jose Drummond Camara Olavo Pena Monken Claudio Gouvea Dos Santos State University of Minas Gerais （UEMG） Design School 31270-010 Brazil Federal University of Ouro Preto （UFOP） ICEB-DEQUI 35400-000 Brazil

Simulation description of a poly(ethylene terephthalate) bottle, blowing through the injection stretch blow molding process, using computer aided engineering softwares and analysis by finite elements method in order to better fit the bottle project using this material and weight reduction. The work was conducted from existing preforms and focused on the design process of the bottles, approach in which the available literature is scarce or nonexistent. The design of a bottle was executed, applied and validated through parametric computer aided design software and finite elements method analysis, allowing the simulation of the blowing process from data input to the process variables listed in the available literature. Using this approach, we simulate the blowing process and the mechanical demands related to the application with the aim of assessing the efficiency of packaging design and enable an efficient and correct sizing of the bottles. The data obtained in simulations were verified by the fabrication of prototypes using the same material, preform and process data considered in the virtual environment. The results indicate the feasibility of producing 500 mL bottles for carbonated soft drinks from 18 g preforms, with a reduction of up to 21% on weight of the packaging, keeping the standard bottle finish PCO-1810-28 mm.

关键词：有限元模拟优化设计重量 PET瓶计算机辅助设计软件聚对苯二甲酸乙二酯吹塑成型工艺包装设计

Supercritical fluid technology as a sustainable alternative method for textile dyeing:An approach on waste,energy,and CO_(2)emission reduction

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Journal of Environmental Sciences 2024年第6期140卷 123-145页

作者： carlos Rafael silva de Oliveira Patrícia Viera de Oliveira Leandro Pellenz Catia Rosana Lange de Aguiar Afonso Henrique da silva Júnior Federal University of Santa Catarina Textile Engineering Department2514 João Pessoa St.BlumenauSC89036-004Brazil Federal University of Santa Catarina Chemical Engineering DepartmentS/n Biotério Central St.FlorianópolisSC88040-900Brazil

The clothing industry is considered one of the most polluting industries on the planet due to the high consumption of water,energy,chemicals/dyes,and high generation of solid waste and *** with environmental concerns,the textile ennoblement sector is the most critical of the textile production chain,especially the traditional dyeing *** an alternative to current problems,dyeing with supercritical CO_(2)(scCO_(2))has been presented as a clean and efficient process for a sustainable textile *** fluid dyeing(SFD)has shown a growing interest due to its significant impact on environmental preservation and social,economic,and financial *** main SFD benefits include economy and reuse of non-adsorbed dyes;reduction of process time and energy expenditure;capture of atmospheric CO_(2)(greenhouse gas);use and recycling of CO_(2)in SFD;generation of carbon credits;water-free process;effluent-free process;reduction of CO_(2)emission and auxiliary *** being still a non-scalable and evolving technology,SFD is the future of *** review presented a comprehensive overview of the environmental impacts caused by traditional processes and confronted the advantages of *** SFD technique was introduced,along with its latest advances and future *** and environmental gains were also discussed.

关键词： Textile industry Supercritical dyeing Sustainable processes Water free dyeing Energy saving Cleaner production

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Concentration of dimension in extremal points of left-half lines in the Lagrange spectrum

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Acta Mathematica Sinica,English Series 2024年

作者： carlos Gustavo MOREIRA Christian Camilo silva VILLAMIL SUSTech International Center for Mathematics Shenzhen Guangdong People's Republic of China and IMPA SUSTech International Center for Mathematics Shenzhen Guangdong People's Republic of China and IMPA

We prove that for any η that belongs to the closure of the interior of the Markov and Lagrange spectra,the sets k-1(（-∞,η]） and k-1（η）,which are the sets of irrational numbers with best constant of Diophantine approximation bounded by η and exactly η respectively,have the same Hausdorff *** also show that,as η varies in the interior of the spectra,this Hausdorff dimension is a strictly increasing function.

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Rotating effects on the photoionization cross-section of a 2D quantum ring

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Communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： carlos Magno O Pereira Frankbelson dos S Azevedo Luís Fernando C Pereira Edilberto O silva Departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. Solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. Specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect

Determination of critical state line(CSL)for silty-sandy iron ore tailings subjected to low-high confining pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1684-1695页

作者： Nilo Cesar Consoli João Vítor de Azambuja Carvalho Alexia Cindy Wagner Hugo carlos Scheuermann Filho Inácio Carvalho Pedro Pazzoto Cacciari João Paulo de Sousa silva Civil Engineering Universidade Federal do Rio Grande do SulPorto AlegreRS90035-190Brazil Exploration and Mineral Projects-Mineral Development Centre VALE S.A.Santa LuziaMG33040-900Brazil Department of Civil Geological and Mining EngineeringPolytechnique MontrealQuebecH3C 3A7Canada

The disposal of filtered tailings in high dry stacks can induce particle breakage,changing the material's behaviour during the structure's *** grading changes influence material properties at the critical state,and this is not mature for intermediate artificial soils(tailings)in a broad range of confining *** this paper,it aims to describe the behaviour of iron ore tailings in a spectrum of confining pressures broader than the reported in previous studies.A series of consolidated drained(CD)triaxial tests was carried out with confining pressures ranging from 0.075 MPa to 120 *** results show that the amount of breakage plays an essential role in the response of iron ore *** existence of curved critical state line(CSL)in both specific volume(ν)-logarithm of mean effective stress(p′)and deviatoric stress(q)-mean effective stress(p′)planes,and different responses in the deviatoric stress-axial strain-volumetric strain curves were *** inverse S-shaped equation was proposed to represent the silty-sandy tailings'behaviour up to high pressures onν-lnp′*** proposed equation provides a basis for enhancing constitutive models and considers the evolution of the grading up to severe loading *** adjustment considered three regions with different responses associated with particle breakage at different pressure levels.

关键词： Tailings Iron ore tailings dry stacking Silty-sandy material Critical state soil mechanics High confining pressures Particle breakage

Unveiling DNA methylation in Alzheimer’s disease:a review of array-based human brain studies

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Neural Regeneration Research 2024年第11期19卷 2365-2376页

作者： Victoria Cunha Alves Eva Carro Joana Figueiro-silva Neurodegenerative Diseases Group Hospital Universitario 12 de Octubre Research Institute(imas12)MadridSpain Network Center for Biomedical Research Neurodegenerative Diseases(CIBERNED)MadridSpain PhD Program in Neuroscience Autonoma de Madrid UniversityMadridSpain Neurotraumatology and Subarachnoid Hemorrhage Group Hospital Universitario 12 de Octubre Research Institute(imas12)MadridSpain Neurobiology of Alzheimer’s Disease Unit Functional Unit for Research Into Chronic DiseasesInstituto de Salud Carlos IIIMadridSpain Institute of Medical Genetics University of ZurichZurichSwitzerland Department of Molecular Life Science University of ZurichZurichSwitzerland

The intricacies of Alzheimer’s disease pathogenesis are being increasingly illuminated by the exploration of epigenetic mechanisms,particularly DNA *** review comprehensively surveys recent human-centered studies that investigate whole genome DNA methylation in Alzheimer’s disease *** examination of various brain regions reveals distinctive DNA methylation patterns that associate with the Braak stage and Alzheimer’s disease *** entorhinal cortex emerges as a focal point due to its early histological alterations and subsequent impact on downstream regions like the ***,ANK1 hypermethylation,a protein implicated in neurofibrillary tangle formation,was recurrently identified in the entorhinal ***,the middle temporal gyrus and prefrontal cortex were shown to exhibit significant hypermethylation of genes like HOXA3,RHBDF2,and MCF2L,potentially influencing neuroinflammatory *** complex role of BIN1 in late-onset Alzheimer’s disease is underscored by its association with altered methylation *** the disparities across studies,these findings highlight the intricate interplay between epigenetic modifications and Alzheimer’s disease *** research efforts should address methodological variations,incorporate diverse cohorts,and consider environmental factors to unravel the nuanced epigenetic landscape underlying Alzheimer’s disease progression.

关键词： Alzheimer’s disease ANK1 BIN1 DNA methylation epigenome-wide association studies HOXA3 MCF2L RHBDF2

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