1,065 research outputs found

    Synthesis and evaluation of influenza A viral neuraminidase candidate inhibitors based on a bicyclo[3.1.0]hexane scaffold

    Get PDF
    We describe the synthesis of constrained oseltamivir analogues designed to mimic the proposed boat conformation of the enzymatic transition state

    Evaluation of different cell disruption processes on encysted cells of Haematococcus pluvialis: effects on astaxanthin recovery and implications for bio-availability

    Get PDF
    Although Haematococcus pluvialis is one of the most importantnatural sources of the carotenoid astaxanthin as a pigmentor for theaquaculture industry, the thick sporopollenin cell wall in the cysts hindersastaxanthin extraction and its subsequent bio-availability to fish. A rangeof physical and chemical processes were tested to promote the disruptionof the encysted cells. The efficacy of these processes was evaluated interms of astaxanthin recovery, which was assessed by determining theextent of leaching of astaxanthin into an organic solvent. The processestested were: autoclave 30 min, 121 °C, 1 atm; HCl 0.1 M, 15min and 30 min; NaOH 0.1 M, 15 min and 30 min; enzymatictreatment with a mixture of 0.1% protease K and 0.5% driselase in aphosphate buffer, pH 5.8, 30 °C, for one hour; spray drying, inlet180 °C, outlet 115 °C; and mechanical disruption, with acell homogeniser developed for this purpose. The mechanical(homogenisation) and autoclave treatments were the most effective in termsof extraction and availability

    Continuous improvement in maintenance: a case study in the automotive industry involving Lean tools

    Get PDF
    Maintenance function assumes a key role in today’s industry. The automotive industry is not an exception and there are strict rules to comply with. Indeed, the IATF 16949:2016 imposes the implementation of key performance indicator as a mean to control the overall manufacturing performance. This work presents a case study carried out in a multinational company related with the production of parts for the automotive industry where it was necessary to implement key performance indicators to comply with the IATF 16949: 2016 standard and a model was also created for the management of spare parts linked to the maintenance of existing equipment. The introduction of these changes forced the application of some Lean tools, with a view to improving procedures and information flows. The work was completed successfully, and key performance indicators were implemented, whose support data, which is now collected and calculated automatically on a routine basis, and the spare-parts management was validated with a view to optimization of warehouse space and at a conveniently low inventory level in this type of parts, without endangering critical equipment in production. The SMED methodology was applied, which allowed the setup time to be reduced by 11%, and the Lean 5S tool was used to organize the mould exchange activities. An OEE of more than 90% has been achieved.info:eu-repo/semantics/publishedVersio

    Physical growth of schoolchildren from the Jequitinhonha Valley, Minas Gerais, Brazil: Comparison with the CDC-2000 reference using the LMS method

    Get PDF
    Objective: To analyse the physical growth of a representative school population sample from the Jequitinhonha Valley, Minas Gerais, Brazil, in comparison with the reference proposed by the Centre for Disease Control and Prevention (CDC-2000). Methods: The sample was composed of 5100 individuals (2730 girls and 2370 boys), aged 6-18 years. Body weight-for-age and height-for-age percentiles were obtained using the LMS method. Statistical and graphical comparisons were made with the corresponding percentiles of the CDC-2000 reference, estimated using the same method. Results: Overall, the calculated values of the L (asymmetry) and the S (variability) parameters were quite similar to the CDC-2000 reference values. However, M(median) was substantially different from the reference used in the study, mainly in schoolchildren over 12-13 years of age of both genders. The magnitude of the deficits of height-for-age and body weight-for-age observed in the schoolchildren from the Jequitinhonha Valley, Minas Gerais, Brazil, varied from 4 to 6 cm and from 3 to 6 kg, respectively. Conclusion: The body weight-for-age and height-for-age percentiles of schoolchildren population in the Jequitinhonha Valley, Minas Gerais, Brazil differed substantially from those referenced

    Evolution in swimming "science" research

    Get PDF
    Swimming seems to be one of the sports more studied . More than one decade ago, Clarys (1996) made an content analysis of the research about swimming. However, in these last 13 years several developments happened in the aquatic activities

    Evolution on Swimming Science Research: content analysis of the “Biomechanics and Medicine in Swimming” Proceedings Books from 1971 to 2006

    Get PDF
    Swimming seems to be one of the sports more studied . More than one decade ago, Clarys (1996) made an content analysis of the research about swimming. However, in these last 13 years several developments happened in the aquatic activities

    Distribution of black flies (Diptera: Simuliidae) in the State of Espírito Santo, Brazil

    Get PDF
    Entre os anos de 2004 e 2008 foram realizadas coletas de Simuliidae em várias localidades no Estado do Espírito Santo, Brasil. No total, 66 córregos e rios das doze principais bacias hidrográficas do estado foram amostrados. Dezessete espécies foram coletadas, sendo que nove delas representam ocorrências novas para o estado (Simulium pertinax, S. jujuyense, S. rubrithorax, S. subnigrum, S. travassosi, S. spinibranchium, S. hirtipupa, S. lutzianum e S. anamariae), duplicando o número de espécies conhecidas no estado.We conducted a freshwater survey from 2004 to 2008 in several localities of Espírito Santo, Brazil. In total, 66 streams and rivers were sampled in the 12 hydrographic basins of the state. We collected and identified 17 species of which nine represent new records (Simulium pertinax, S. jujuyense, S. rubrithorax, S. subnigrum, S. travassosi, S. spinibranchium, S. hirtipupa, S. lutzianum e S. anamariae). These findings doubled the number of records of black fly species to the State of Espírito Santo, Brazil

    Noncommutative quantum mechanics and Bohm's ontological interpretation

    Full text link
    We carry out an investigation into the possibility of developing a Bohmian interpretation based on the continuous motion of point particles for noncommutative quantum mechanics. The conditions for such an interpretation to be consistent are determined, and the implications of its adoption for noncommutativity are discussed. A Bohmian analysis of the noncommutative harmonic oscillator is carried out in detail. By studying the particle motion in the oscillator orbits, we show that small-scale physics can have influence at large scales, something similar to the IR-UV mixing

    Self-Similar Factor Approximants

    Full text link
    The problem of reconstructing functions from their asymptotic expansions in powers of a small variable is addressed by deriving a novel type of approximants. The derivation is based on the self-similar approximation theory, which presents the passage from one approximant to another as the motion realized by a dynamical system with the property of group self-similarity. The derived approximants, because of their form, are named the self-similar factor approximants. These complement the obtained earlier self-similar exponential approximants and self-similar root approximants. The specific feature of the self-similar factor approximants is that their control functions, providing convergence of the computational algorithm, are completely defined from the accuracy-through-order conditions. These approximants contain the Pade approximants as a particular case, and in some limit they can be reduced to the self-similar exponential approximants previously introduced by two of us. It is proved that the self-similar factor approximants are able to reproduce exactly a wide class of functions which include a variety of transcendental functions. For other functions, not pertaining to this exactly reproducible class, the factor approximants provide very accurate approximations, whose accuracy surpasses significantly that of the most accurate Pade approximants. This is illustrated by a number of examples showing the generality and accuracy of the factor approximants even when conventional techniques meet serious difficulties.Comment: 22 pages + 11 ps figure

    Micromachined III-V cantilevers for AFM-tracking scanning Hall probe microscopy

    Get PDF
    In this paper we report the development of a new III-V cantilever-based atomic force sensor with piezoresistive detection and an integrated Hall probe for scanning Hall probe microscopy. We give detailed descriptions of the fabrication process and characterization of the new integrated sensor, which will allow the investigation of magnetic samples with no sample preparation at both room and cryogenic temperatures. We also introduce a novel piezoresistive material based on the ternary alloy n+-Al0.4Ga0.6As which allows us to achieve a cantilever deflection sensitivity ΔR/(RΔz) = 2 × 10-6 Å-1 at room temperature
    corecore