443 research outputs found

    A robot-based burr measurement system for the automotive industry

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    Burrs are often difficult to detect and measure because of their intrinsic variability in shape and dimension. No automotive standard had been established about their acceptable dimensions and measurement techniques for sheet steel products. For the automotive industry, even burrs of the size of 100 μm are perceived as damaging because of their dramatic impact upon panel corrosion resistance and assembly performance. It is critical to measure burrs during panel manufacture in order to control the process. The characterization of the typical burr produced has been carried out employing 3D measurements with a surface profilometer and a SEM. This analysis has shown a typical triangular burr shape and some characteristic dimensions. A contact method and two laser-triangulation systems have been developed. The instrument accuracy was analyzed, based upon a full factorial experimentation over a set of typical panels edges

    Subcutaneous adipose tissue classification

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    The developments in the technologies based on the use of autologous adipose tissue attracted attention to minor depots as possible sampling areas. Some of those depots have never been studied in detail. The present study was performed on subcutaneous adipose depots sampled in different areas with the aim of explaining their morphology, particularly as far as regards stem niches. The results demonstrated that three different types of white adipose tissue (WAT) can be differentiated on the basis of structural and ultrastructural features: deposit WAT (dWAT), structural WAT (sWAT) and fibrous WAT (fWAT). dWAT can be found essentially in large fatty depots in the abdominal area (periumbilical). In the dWAT, cells are tightly packed and linked by a weak net of isolated collagen fibers. Collagenic components are very poor, cells are large and few blood vessels are present. The deep portion appears more fibrous then the superficial one. The microcirculation is formed by thin walled capillaries with rare stem niches. Reinforcement pericyte elements are rarely evident. The sWAT is more stromal; it is located in some areas in the limbs and in the hips. The stroma is fairly well represented, with a good vascularity and adequate staminality. Cells are wrapped by a basket of collagen fibers. The fatty depots of the knees and of the trochanteric areas have quite loose meshes. The fWAT has a noteworthy fibrous component and can be found in areas where a severe mechanic stress occurs. Adipocytes have an individual thick fibrous shell. In conclusion, the present study demonstrates evident differences among subcutaneous WAT deposits, thus suggesting that in regenerative procedures based on autologous adipose tissues the sampling area should not be randomly chosen, but it should be oriented by evidence based evaluations. The structural peculiarities of the sWAT, and particularly of its microcirculation, suggest that it could represent a privileged source for regenerative procedures based on autologous adipose tissues

    The trochanteric fat pad

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    Technological developments based on the use of autologous white adipose tissue (WAT) attracted attention to minor fat depots as possible sources of adipose tissue. In plastic surgery, the trochanteric fatty pad is one of the most used WAT depots for its location and organoleptic characteristics that make it particularly suitable for reconstructive procedures. Despite its wide use in clinic, the structure of this depot has never been studied in detail and it is not known if structural differences exist among trochanteric fat and other subcutaneous WAT depots. The present study was performed on trochanteric fat pad with the aim to clarify the morphology of its adipocytes, stroma and microcirculation, with particular reference to the stem niches. Histological and ultrastructural studies showed that the main peculiar feature of the trochanteric fat concerns its stromal component, which appears less dense than in the other subcutaneous WATs studied. The intra-parenchymal collagen stroma is poor and the extracellular compartment shows large spaces, filled with electron-light material, in which isolated collagen bundles are present. The adipocytes are wrapped in weak and easily detachable collagen baskets. These connective sheaths are very thin compared to the sheaths in other subcutaneous WAT depots. The capillaries are covered by large, long and thin elements surrounded by an external lamina; these perivascular cells are poor in organelles and mainly contain poly-ribosomes. In conclusion, when compared to other WAT deposits, the trochanteric fatty pad shows structural peculiarities in its stroma and microcirculation suggesting a high regenerative potential. Resistance, dissociability, microvascular weft and high regenerative potential make the trochanteric fatty pad a privileged source for harvesting in autologous WAT-based regenerative procedures

    Perfil hormonal em mudas Bordô/VR043-43 pós-forçagem a partir de estacas com diferentes épocas de coleta e tempos de armazenagem.

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    Híbridos Vitis rotundifolia (ex.: VR043-43) têm sido empregados como porta-enxertos em vinhedos com problemas de estresses bióticos, principalmente no estado de Santa Catarina. Entretanto, a produção de mudas é dificultada com estacas lignificadas, pela restrição em calogênese de enxertia e enraizamento desses genótipos.CLAUDIO DE ANDRADE BARROS, CNPUV, 29742

    Qualidade de mudas de videira em pós-forçagem submetidas a aplicação de etefom, diferentes épocas de coleta e tempo de câmara fria.

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    A procura por mudas de videira com qualidade superior tem se intensificado ultimamente, exigindo aprimoramento no processo de produção pelos viveiristas. A cultivar Bordô (B) enxertada nos porta-enxertos P1103 (P) e VR043-43 (VR) são as combinações tradicionais utilizadas no Rio Grande do Sul e em Santa Catarina, respectivamente.Daniel Antunes Souza, 333734, CNPU

    Dark chocolate modulates platelet function with a mechanism mediated by flavan-3-ol metabolites

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    Cocoa is a rich source bioactive compounds, i.e., flavan-3-ols, and its consumption has been associated with several beneficial effects, such as the positive modulation of the hemostasis targeted by the platelet function. However, these phenolic compounds have a very low bioavailability and extensively undergo phase I and II metabolism, with the appearing into the bloodstream of (epi) catechin conjugates and phenyl-g-valerolactones and their conjugates, at different times. The aims of this study were to explore the effect of dark chocolate on platelet function and to investigate the relationship between this interplay and flavan-3-ol derived metabolites. Eighteen healthy male volunteers ingested 50 g of 90% cocoa chocolate within 5 minutes. Blood samples were collected immediately before chocolate ingestion (T0) and 4 hours afterwards (T1). Platelet function analyzer (PFA)-100 closure time was assessed using collagen/adenosine-50-diphosphate (COL/ADP) and collagen/epinephrine (COL/EPI) cartridges. Plasma flavan-3-ol metabolites were identified and quantified by means of liquid chromatography coupled to a triple quadrupole mass spectrometer (UHPLC-ESI-MS/MS). Results evidenced a significant increase of COL/ADP-induced PFA-100 closure time, but not COL/EPI, 4 hours after ingestion of dark chocolate. Total plasma structurally-related (epi)catechin metabolite (SREM) concentration significantly increased at T1, together with 4 out of the 6 detected metabolites. Total phenyl-g-valerolactone concentrations remained unchanged. Spearman correlations evidenced a strong correlation between COL/ADP closure time and SREMs, mainly led by (epi)catechin-sulfate isomers. These data confirm that the potential beneficial effect of dark chocolate on primary hemostasis may be mediated by flavan-3-ol circulating metabolites

    Zoneamento das condições atuais e futuras de frio para o controle natural da endodormência em clones de Moscato Branco e cvs Vitis labrusca no sul do Brasil.

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    Como uma planta de clima temperado, a videira necessita de um acúmulo de horas frio (HF, T<7,2°C) para superar o estado de endodormência e ter uma brotação regular, o que é variável entre genótipos. Confrontando essa demanda com as previsões de mudanças climáticas e diminuição de frio, o presente trabalho objetivou contabilizar e delimitar o zoneamento atual e futuro para o cultivo de diferentes clones de Moscato Branco (Vitis vinifera) e cultivares Vitis labrusca

    Magnetic resonance imaging of ultrasmall superparamagnetic iron oxide-labeled exosomes from stem cells: a new method to obtain labeled exosomes

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    Purpose: Recent findings indicate that the beneficial effects of adipose stem cells (ASCs), reported in several neurodegenerative experimental models, could be due to their paracrine activity mediated by the release of exosomes. The aim of this study was the development and validation of an innovative exosome-labeling protocol that allows to visualize them with magnetic resonance imaging (MRI).Materials and methods: At first, ASCs were labeled using ultrasmall superparamagnetic iron oxide nanoparticles (USPIO, 4\u20136 nm), and optimal parameters to label ASCs in terms of cell viability, labeling efficiency, iron content, and magnetic resonance (MR) image contrast were investigated. Exosomes were then isolated from labeled ASCs using a standard isolation protocol. The efficiency of exosome labeling was assessed by acquiring MR images in vitro and in vivo as well as by determining their iron content. Transmission electron microscopy images and histological analysis were performed to validate the results obtained.Results: By using optimized experimental parameters for ASC labeling (200 \ub5g Fe/mL of USPIO and 72 hours of incubation), it was possible to label 100% of the cells, while their viability remained comparable to unlabeled cells; the detection limit of MR images was of 102 and 2.5 7103 ASCs in vitro and in vivo, respectively. Exosomes isolated from previously labeled ASCs retain nanoparticles, as demonstrated by transmission electron microscopy images. The detection limit by MRI was 3 \ub5g and 5 \ub5g of exosomes in vitro and in vivo, respectively.Conclusion: We report a new approach for labeling of exosomes by USPIO that allows detection by MRI while preserving their morphology and physiological characteristics

    Polarizing a stored proton beam by spin flip?

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    We discuss polarizing a proton beam in a storage ring, either by selective removal or by spin flip of the stored ions. Prompted by recent, conflicting calculations, we have carried out a measurement of the spin flip cross section in low-energy electron-proton scattering. The experiment uses the cooling electron beam at COSY as an electron target. The measured cross sections are too small for making spin flip a viable tool in polarizing a stored beam. This invalidates a recent proposal to use co-moving polarized positrons to polarize a stored antiproton beam.Comment: 18 pages, 6 figure

    Deficiência de nutrientes com efeitos no desenvolvimento de morangueiros.

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    A adubação do morangueiro é uma das principais práticas responsáveis pelo aumento da produção. Entretanto, ainda são insuficientes as informações sobre o efeito da omissão dos nutrientes minerais sobre o desenvolvimento do morangueiro. Neste contexto, o objetivo deste trabalho foi avaliar o crescimento dos morangueiros, visualizar os sintomas de deficiência nutricionais e os teores de nutrientes nas folhas decorrentes da omissão de macro e micro nutrientes. O delineamento experimental utilizado foi o inteiramente casualizado, com dez tratamentos e três repetições. Os tratamentos constituíram-se de solução completa e omissão individual de cada um dos seguintes nutrientes: nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca), magnésio (Mg), cobre (Cu), manganês (Mn), zinco (Zn) e ferro (Fe). Avaliou-se: a massa fresca e seca da raiz, da parte aérea e da coroa, número de folhas e coroas, teores de macro e micronutrientes nas folhas e sintomas visuais de deficiência nutricional. A massa fresca e seca da parte aérea, o número de coroa e o número de folhas são mais prejudicados pela ausência de macronutrientes. O desenvolvimento do sistema radicular do morangueiro é menor na omissão dos macronutrientes. Menores teores de N, P, K, Ca, Mg e Fe nas folhas de morangueiro ocorrem quando são realizadas omissão desses elemento
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