524 research outputs found
Crystallographic texture evolution in Ti–35Nb alloy deformed by cold rolling
This work presents the results of a microstructural characterization of the Ti–35Nb alloy deformed by cold rolling. Initially, samples of the Ti–35Nb (wt%) alloy were obtained by electric arc melting. After melting, these samples were solution heat-treated at 1000 °C for 8 h and water quenched. The resulting microstructure was composed of β-phase (bcc) combined with orthorhombic martensite (α″). Samples were cold-rolled in multiple passes to reduce their thickness by up to 85% without intermediary annealing. They were then characterized by light optical microscopy, X-ray diffraction and Vickers hardness measurements. Young’s modulus was determined by ultrasonic methods and nanoindentation measurements. The texture evolution and orientation relationship between phases were studied by X-ray diffraction and electron backscatter diffraction (EBSD). The results reveal the presence of shear bands in the deformed samples, an orientation of the orthorhombic martensite phase in relation to the rolling direction, and variations of Young’s modulus in response to deformation. The textural results of the β-phase show a typical bcc rolling texture with strong (1 1 0) fiber and weak (1 1 1) fiber. The intensity of the (1 1 0) fiber increases with deformation60653660CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPNão temNão temNão temThe authors gratefully acknowledge the Brazilian research funding agencies FAPESP (State of São Paulo Research Foundation), CNPq (National Council for Scientific and Technological Development) and CAPES (Federal Agency for the support and Evaluation of Graduate Education) for their financial support of this wor
ÉRICO GOBBI: RESGATANDO A MEMÓRIA DE UM ESCULTOR RIOGRANDINO ATRAVÉS DA ANÁLISE E DIAGNÓSTICO DE SUAS OBRAS COMO PATRIMÔNIO CULTURAL
O presente trabalho de pesquisa versará sobre o escultor riograndino Érico Gobbi e tem por objetivo diagnosticar e inventariar o acervo de obras deixado pelo artista. A coleção de Gobbi encontra-se boa parte em sua galeria de arte; são bustos de políticos, filósofos, pessoas conhecidas nacionalmente, medalhões, fotos, troféus, esculturas em vários tamanhos e condecorações que recebeu durante sua vida. Seu acervo externo está exposto em praças públicas da cidade e a mais conhecida de suas esculturas é a estátua Mãe Iemanjá, que localiza-se na praia do Cassino; sua coleção conta com mais de 100 obras. A preservação da galeria e das obras deixadas pelo o artista fica sob a responsabilidade do filho Edisom Gobbi ; as obras em lugares públicos estão sob a responsabilidade da prefeitura de Rio Grande. O escultor deixou uma herança cultural ao povo riograndino, a qual deverá ser divulgada e trabalhada sob os aspectos culturais, como patrimônio e memória da cidade do Rio Grande
Benchmarking a highly selective USP30 inhibitor for enhancement of mitophagy and pexophagy
The deubiquitylase USP30 is an actionable target considered for treatment of conditions associated with defects in the PINK1-PRKN pathway leading to mitophagy. We provide a detailed cell biological characterization of a benzosulphonamide molecule, compound 39, that has previously been reported to inhibit USP30 in an in vitro enzymatic assay. The current compound offers increased selectivity over previously described inhibitors. It enhances mitophagy and generates a signature response for USP30 inhibition after mitochondrial depolarization. This includes enhancement of TOMM20 and SYNJ2BP ubiquitylation and phosphoubiquitin accumulation, alongside increased mitophagy. In dopaminergic neurons, generated from Parkinson disease patients carrying loss of function PRKN mutations, compound 39 could significantly restore mitophagy to a level approaching control values. USP30 is located on both mitochondria and peroxisomes and has also been linked to the PINK1-independent pexophagy pathway. Using a fluorescence reporter of pexophagy expressed in U2OS cells, we observe increased pexophagy upon application of compound 39 that recapitulates the previously described effect for USP30 depletion. This provides the first pharmacological intervention with a synthetic molecule to enhance peroxisome turnover
D terms from D-branes, gauge invariance and moduli stabilization in flux compactifications
We elucidate the structure of D terms in N=1 orientifold compactifications
with fluxes. As a case study, we consider a simple orbifold of the type-IIA
theory with D6-branes at angles, O6-planes and general NSNS, RR and
Scherk-Schwarz geometrical fluxes. We examine in detail the emergence of D
terms, in their standard supergravity form, from an appropriate limit of the
D-brane action. We derive the consistency conditions on gauged symmetries and
general fluxes coming from brane-localized Bianchi identities, and their
relation with the Freed-Witten anomaly. We extend our results to other N=1
compactifications and to non-geometrical fluxes. Finally, we discuss the
possible role of U(1) D terms in the stabilization of the untwisted moduli from
the closed string sector.Comment: 1+31 pages, 1 figur
Root dentinal microcracks: a post-extraction experimental phenomenon?
Aim
To investigate the prevalence, location and pattern of pre‐existing microcracks in non‐endodontically treated teeth from fresh cadavers. Micro‐computed tomography (micro‐CT) technology was used as the analytical tool enabling full screening of the root dentine with the teeth retained in their original alveolar socket.
Methodology
As a pilot study and to validate the present method, a series of 4 high‐resolution scans were performed on one bone‐block specimen with teeth collected post‐mortem: (i) entire bone‐block including the teeth, (ii) second molar tooth extracted atraumatically from the bone‐block, (iii) extracted tooth dehydrated to induce dentinal defects and (iv) entire bone‐block following reinsertion of the extracted tooth into its matching alveolar socket. In the main study, forty‐two dentoalveolar maxillary and mandibular bone‐blocks each containing 3–5 adjacent teeth (a total of 178 teeth) were collected post‐mortem and scanned in a micro‐CT device. All cross‐section images of the 178 teeth (n = 65 530) were screened from the cementoenamel junction to the apex to identify the presence of dentinal defects.
Results
In the pilot study, the microcracks observable when the dehydrated tooth was outside the bone‐block remained detectable when the entire bone‐block plus reinserted tooth was scanned. This means that the screening process revealed the presence of the same microcracks in both experimental situations (the tooth outside and inside the maxillary bone‐block). From a total of 178 teeth in the bone‐blocks removed from cadavers, 65 530 cross‐sectional images were analysed and no dentinal microcracks were detected.
Conclusions
This in situ cadaveric model revealed the lack of pre‐existing dentinal microcracks in non‐endodontically treated teeth. Thus, the finding of dentinal microcracks observed in previous cross‐sectional images of stored extracted teeth is unsound and not valid. It should be assumed that microcracks observed in stored extracted teeth subjected to root canal procedures are a result of the extraction process and/or the post‐extraction storage conditions. Therefore, as a consequence, the presence of such dentinal microcracks in stored extracted teeth – observable in cross‐sectional images of the roots – should be referred to as experimental dentinal microcracks
Epidemiology of lobomycosis-like disease in bottlenose dolphins <i>Tursiops</i> spp. from South America and southern Africa
We report on the epidemiology of lobomycosis-like disease (LLD), a cutaneous disorder evoking lobomycosis, in 658 common bottlenose dolphins Tursiops truncatus from South America and 94 Indo-Pacific bottlenose dolphins T. aduncus from southern Africa. Photographs and stranding records of 387 inshore residents, 60 inshore non-residents and 305 specimens of undetermined origin (inshore and offshore) were examined for the presence of LLD lesions from 2004 to 2015. Seventeen residents, 3 non-residents and 1 inshore dolphin of unknown residence status were positive. LLD lesions appeared as single or multiple, light grey to whitish nodules and plaques that may ulcerate and increase in size over time. Among resident dolphins, prevalence varied significantly among 4 communities, being low in Posorja (2.35%, n = 85), Ecuador, and high in Salinas, Ecuador (16.7%, n = 18), and Laguna, Brazil (14.3%, n = 42). LLD prevalence increased in 36 T. truncatus from Laguna from 5.6% in 2007-2009 to 13.9% in 2013-2014, albeit not significantly. The disease has persisted for years in dolphins from Mayotte, Laguna, Salinas, the Sanquianga National Park and Bahía Málaga (Colombia) but vanished from the Tramandaí Estuary and the Mampituba River (Brazil). The geographical range of LLD has expanded in Brazil, South Africa and Ecuador, in areas that have been regularly surveyed for 10 to 35 yr. Two of the 21 LLD-affected dolphins were found dead with extensive lesions in southern Brazil, and 2 others disappeared, and presumably died, in Ecuador. These observations stress the need for targeted epidemiological, histological and molecular studies of LLD in dolphins, especially in the Southern Hemisphere
MOF-Based Materials with Sensing Potential: Pyrrolidine-Fused Chlorin at UiO-66(Hf) for Enhanced NO2 Detection
The correct use of the vernacular names for South American dolphins genus Sotalia Gray (Mammalia, Cetacea, Delphinidae)
Molecular characterization of two rocio flavivirus strains isolated during the encephalitis epidemic in são paulo state, brazil and the development of a one-step rt-pcr assay for diagnosis
Preparation of Luminescent Metal-Organic Framework Films by Soft-Imprinting for 2,4-Dinitrotoluene Sensing
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