283 research outputs found

    Effect of bentonite characteristics on the elemental composition of wine

    Get PDF
    Physical, chemical, and mineralogical characteristics of six bentonites were assessed and related to their elemental release to wine. Extraction essays of bentonites in wine at three pH levels were carried out. The multielemental analysis of bentonites and wines was performed by atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Bentonite addition resulted in significantly higher concentrations of Li, Be, Na, Mg, Al, Ca, Sc, V, Mn, Fe, Co, Ni, Ga, Ge, As, Sr, Y, Zr, Nb, Mo, Cd, Sn, Sb, Ba, W, Tl, Bi, and W. In contrast, the concentrations of B, K, Cu, Zn, and Rb significantly decreased. A strong correlation between Na concentrations of treated wines and its content in bentonite exchange complex was observed. Al and Fe contents reflected bentonite extractable aluminous and ferruginous constituents, while Be, Mg, Ca, V, Mn, Ni, Ge, Zr, Nb, Mo, Sn, Sb, Tl, Pb, and U concentrations reflected the elemental composition of bentonites. Several nonconformances with OIV specifications demonstrated the need for an effective control

    Micromegas operation in high pressure xenon: charge and scintillation readout

    Full text link
    The operational characteristics of a Micromegas operating in pure xenon at the pressure range of 1 to 10 bar are investigated. The maximum charge gain achieved in each pressure is approximately constant, around 4x10^2, for xenon pressures up to 5 bar and decreasing slowly above this pressure down to values somewhat above 10^2 at 10 bar. The MM presents the highest gains for xenon pressures above 4 bar, when compared to other micropattern gaseous multipliers. The lowest energy resolution obtained for X-rays of 22.1 keV exhibits a steady increase with pressure, from 12% at 1bar to about 32% at 10 bar. The effective scintillation yield, defined as the number of photons exiting through the MM mesh holes per primary electron produced in the conversion region was calculated. This yield is about 2x10^2 photons per primary electron at 1 bar, increasing to about 6x10^2 at 5 bar and, then, decreasing again to 2x10^2 at 10 bar. The readout of this scintillation by a suitable photosensor will result in higher gains but with increased statistical fluctuations.Comment: 22 pages, 11 figure

    I Ciclo de Conferências : Conselho Técnico Científico : temas atuais em investigação

    Get PDF
    A obra é constituída pelos resumos das comunicações apresentadas pelos docentes da Escola Superior Agrária do Instituto Politécnico de Castelo Branco e são referentes aos projetos de investigação nos quais estão envolvidos.O Conselho Técnico-Científico (CTC) da Escola Superior Agrária tomou posse no dia 9 de Fevereiro de 2010. As suas primeiras acções orientaram-se no sentido de dar cumprimento ao estabelecido nos Estatutos da Escola Superior Agrária do Instituto Politécnico de Castelo Branco, que entraram em vigor a partir de 14 de Janeiro de 2010. Estas acções centraram-se na re-organização interna da estrutura técnica e científica, na definição das estratégias de formação e de investigação, desenvolvimento e inovação (ID&I) da Escola Superior Agrária. Enquadrada nesta estratégia, o CTC considerou oportuno promover um ciclo de conferências, com o principal objectivo de criar um meio de apresentação e debate público do trabalho de ID&I desenvolvido por docentes e técnicos que possibilitasse, nas áreas de intervenção da ESA, o desenvolvimento de novas ideias e a criação de sinergias para estabelecimento de trabalhos pluridisciplinares e parcerias, não só a nível interno como também com stakeholders. A publicação das conferências realizadas neste primeiro mandato (2010-2012), disponibiliza a informação para um público mais alargado, visando contribuir de uma forma concreta para o desenvolvimento da região, aspecto de interesse prioritário na missão do IPCB/ESA

    Estudo de caso da gestão de filas em uma unidade de saúde

    Get PDF
    Na área da saúde, é de extrema importância que o atendimento e tratamento do utente seja efetivo, sobretudo executado com rapidez. Com o crescimento da população, as pessoas buscam mais os serviços de saúde, o que afeta a oferta de serviços, profissionais e impacta no tempo de espera. Este estudo foi motivado pelo interesse em otimizar a gestão de filas numa unidade de saúde do distrito de Bragança, visando reduzir os tempos de espera para a realização de serviços médicos, garantindo que o utente seja atendido com qualidade, de forma ética e humana, e com alto nível técnico dos profissionais. O objetivo é reduzir o elevado tempo de espera que os utentes encontram ao solicitarem atendimento na unidade de saúde.info:eu-repo/semantics/publishedVersio

    Study of Heparin in Intestinal Ischemia and Reperfusion in Rats: Morphologic and Functional Evaluation

    Get PDF
    AbstractTo study whether treatment with heparin (HEP) attenuates intestinal dysfunction caused by ischemia (I) and reperfusion (R), rats were treated with HEP (100 U/kg intravenously) or saline solution (SS) before I (60 min), which was produced by occlusion of the superior mesenteric artery, and R (120 min). After I or I/R, we mounted 2-cm jejunal segment in an organ bath to study neurogenic contractions stimulated by electrical pulses or KCl, using a digital recording system. Thin jejunal slices were stained with hematoxylin and eosin for optical microscopy. Compared with the sham group, jejunal contractions were similar in the I + HEP and the I/R + HEP groups, but reduced in the I + SS and the I/R + SS groups. The jejunal enteric nerves were damaged in the I + SS and the I/R + SS, but not in the I + HEP and the I/R + HEP cohorts. These results suggested that HEP attenuated intestinal dysfunction caused by I and I/R

    General-purpose tool for the simulation and analysis of maintenance data

    Get PDF
    This paper covers general mathematical and simulation models for the reliability and availability analysis of repairable systems along with estimation methods and model selection criterion. A combined mathematical and simulation model is proposed, based on the trend-renewal process. This model is then integrated into a generalpurpose tool, for automated modelling of repairable systems. Estimators for different performance measures of the systems are presented. Furthermore, a preliminary quantitative study is conducted on real data from the food industry together with a presentation of the implemented tool functionalities.info:eu-repo/semantics/publishedVersio

    Novel downstream process and analytical tools developed for Influenza VLP vaccine

    Get PDF
    Vaccination remains the most effective way to prevent the infection with Influenza viruses. However, their constant antigenic drift implies that current human Influenza vaccines need to be annually updated with high inherent costs. Virus-like particles (VLPs) have become widely used as vaccine candidates because of their versatility, immunogenicity, and safety profile. In this iBET project we are attempting to produce a candidate for a universal vaccine for which 35 different VLPs (mono, trivalent and pentavalent) were purified. Here we describe three recent advances on Influenza VLPs bioprocessing: two new analytical tools and the development of an integrated all filtration purification process, inserted in the “anything but chromatography” concept. The first method is a label-free tool that uses Biolayer interferometry technology applied on an Octet platform to quantify Influenza VLPs at all stages of DSP. Human and avian sialic acid receptors were used, in order to quantify hemagglutinin (HA) content in several mono- and multivalent Influenza VLP strains. The applied method was able to detect and quantify HA from crude sample up to final VLP product with high throughput, real-time results and improved detection limits, when compared to traditional approaches, crucial for in-line monitoring of DSP. Using a click-chemistry approach that involves Azidohomoalanine incorporation and functionalization, Influenza VLPs were selectively and fluorescently tagged. Taking into account that this chemical tag does not affect particle size, charge and biological activity we report here a valuable tool to online/at-line product monitoring during DSP optimization of virus related biopharmaceuticals. Moreover, using this tool coupled with FACS we were able to discriminate between VLPs and baculovirus, the major impurity of the system. The proposed all-filtration process will be described, with special focus on the clarification stage, followed by multiple ultrafiltration and diafiltration steps to achieve the needed concentration and purity specifications. Using this all-filtration platform, we are able to speed up the time process, to improve the scale-up and to reduce costs due to the removal of chromatographic steps

    D* Production in Deep Inelastic Scattering at HERA

    Get PDF
    This paper presents measurements of D^{*\pm} production in deep inelastic scattering from collisions between 27.5 GeV positrons and 820 GeV protons. The data have been taken with the ZEUS detector at HERA. The decay channel D+(D0Kπ+)π+D^{*+}\to (D^0 \to K^- \pi^+) \pi^+ (+ c.c.) has been used in the study. The e+pe^+p cross section for inclusive D^{*\pm} production with 5<Q2<100GeV25<Q^2<100 GeV^2 and y<0.7y<0.7 is 5.3 \pms 1.0 \pms 0.8 nb in the kinematic region {1.3<pT(D±)<9.01.3<p_T(D^{*\pm})<9.0 GeV and η(D±)<1.5| \eta(D^{*\pm}) |<1.5}. Differential cross sections as functions of p_T(D^{*\pm}), η(D±),W\eta(D^{*\pm}), W and Q2Q^2 are compared with next-to-leading order QCD calculations based on the photon-gluon fusion production mechanism. After an extrapolation of the cross section to the full kinematic region in p_T(D^{*\pm}) and η\eta(D^{*\pm}), the charm contribution F2ccˉ(x,Q2)F_2^{c\bar{c}}(x,Q^2) to the proton structure function is determined for Bjorken xx between 2 \cdot 104^{-4} and 5 \cdot 103^{-3}.Comment: 17 pages including 4 figure
    corecore