Sao Paulo State University

About: Sao Paulo State University is a education organization based out in São Paulo, Brazil. It is known for research contribution in the topics: Population & Context (language use). The organization has 55715 authors who have published 100436 publications receiving 1375332 citations.

Seed lipases: sources, applications and properties - a review

Abstract: - This paper provides an overview regarding the main aspects of seed lipases, such as the reactions catalyzed, physiological functions, specificities, sources and applications. Lipases are ubiquitous in nature and are produced by several plants, animals and microorganisms. These enzymes exhibit several very interesting features, such as low cost and easy purification, which make their commercial exploitation as industrial enzymes a potentially attractive alternative. The applications of lipases in food, detergents, oils and fats, medicines and fine chemistry, effluent treatment, biodiesel production and in the cellulose pulp industry, as well as the main sources of oilseed and cereal seed lipases, are reviewed. Keywords : Vegetable Lipases; Reactions; Sources; Application. INTRODUCTION Lipase enzymes have become more and more prominent on the enzyme biotechnology scenario due to their versatility for hydrolysis and synthesis, their catalytic reactions often being chemo-selective, region-selective or enantio-selective. Lipases are used in many sectors such as the food, pharmaceutical, fine chemical, oil chemical, biodiesel and industrial detergent industries (Freire and Castilho 2008, Alonso et al. 2005). The participation of lipases in the worldwide enzyme industry market has grown significantly and it is believed that, in the future, they will acquire importance comparable to that of the peptidases, which currently represent 25 to 40% of industrial enzyme sales (Hasan et al. 2006). Lipases act, by definition, at the organic-aqueous interface, catalyzing the hydrolysis of ester-carboxylate bonds and releasing fatty acids and organic alcohols (Pereira et al., 2003; Leal et al. 2002; Kamimura et al., 1999; Mercon et al. 1997). However, as Pottevin showed for the first time in 1906, in water-restricted environments, the reverse reaction (esterification) or even various transesterification reactions can occur (Freire and Castilho 2008, Castro et al. 2000). The term transesterification refers to the exchange of groups between an ester and an acid (acidolysis), between an ester and an alcohol (alcoholysis) or between two esters (interesterification). Their ability to catalyze these reactions with great efficiency, stability and versatility makes these enzymes highly attractive from a commercial point of view (Figure 1).

Direct limits on the B-s(0) oscillation frequency

Abstract: We report the first direct two-sided bound on the $B^0_s$ oscillation frequency using a large sample of $B^0_s$ semileptonic decays corresponding to approximately 1 fb$^{-1}$ of integrated luminosity collected by the \dzer\ experiment in 2002--2006 during Run II of the Fermilab Tevatron Collider. The flavor (i.e., $B^0_s$ or $\bar{B}^0_s$) of the \bs meson at the time of production was found using an opposite-side tagging technique, and the flavor at the time of decay was determined from the charge of the muon in the partially reconstructed decay $\bs\to \mu^{+}D_{s}^{-}X$, $D_{s}^{-}\to \phi \pi^{-}$, $\phi\to K^{+}K^{-}$. A likelihood scan over the oscillation frequency, $\Delta m_s$, gives a most probable value of 19 ps$^{-1}$ and a range of $17 < \Delta m_s < 21$ ps$^{-1}$ at the 90% C.L. At $\Delta m_s=19$ ps$^{-1}$, the amplitude method yields a result that deviates from the hypothesis of an oscillation amplitude of zero by 2.5 standard deviations, corresponding to a two-sided C.L. of 1%.

Combined search for electroweak production of charginos and neutralinos in proton-proton collisions at √s=13 TeV

Abstract: A statistical combination of several searches for the electroweak production of charginos and neutralinos is presented. All searches use proton-proton collision data at $ \sqrt{s}=13 $ TeV, recorded with the CMS detector at the LHC in 2016 and corresponding to an integrated luminosity of 35.9 fb$^{−1}$. In addition to the combination of previous searches, a targeted analysis requiring three or more charged leptons (electrons or muons) is presented, focusing on the challenging scenario in which the difference in mass between the two least massive neutralinos is approximately equal to the mass of the Z boson. The results are interpreted in simplified models of chargino-neutralino or neutralino pair production. For chargino-neutralino production, in the case when the lightest neutralino is massless, the combination yields an observed (expected) limit at the 95% confidence level on the chargino mass of up to 650 (570) GeV, improving upon the individual analysis limits by up to 40 GeV. If the mass difference between the two least massive neutralinos is approximately equal to the mass of the Z boson in the chargino-neutralino model, the targeted search requiring three or more leptons obtains observed and expected exclusion limits of around 225 GeV on the second neutralino mass and 125 GeV on the lightest neutralino mass, improving the observed limit by about 60 GeV in both masses compared to the previous CMS result. In the neutralino pair production model, the combined observed (expected) exclusion limit on the neutralino mass extends up to 650–750 (550–750) GeV, depending on the branching fraction assumed. This extends the observed exclusion achieved in the individual analyses by up to 200 GeV. The combined result additionally excludes some intermediate gaps in the mass coverage of the individual analyses.

Development of Ti-Mo alloys for biomedical applications: Microstructure and electrochemical characterization

Abstract: Ti–Mo alloys from 4 to 20 Mo wt.% were arc-melted. Their compositions and surfaces were analyzed by EDX, XRF and SEM. The Mo mapping shows a homogeneous distribution for all alloys. The XRD analysis showed that the crystal structure of the alloys is sensitive to the Mo concentration; a mixture of the hexagonal α′ and orthorhombic α″ phases was observed for the Ti–4Mo alloy, and the α″ phase is observed almost exclusively when the concentration of Mo added to the Ti reaches 6%. A significant retention of the β phase is observed for the alloy containing 10% Mo, while at higher Mo concentrations (15% and 20%), retention of phase β is only verified. Preliminary electrochemical studies have indicated a valve-metal behavior and good corrosion resistance in aerated Ringer solution for all alloys.