167 research outputs found
Measurement of residual nucleus cross sections and recoil energies in p + Fe collisions at 300, 500, 750, 1000 and 1500 MeV
The production of residual nuclei in p + Fe collisions has been measured at GSI on the FRS facility by means of the reverse kinematic techniques at 300, 500, 750, 1000 and 1500 MeV/A. The cross-sections larger than 0.01 mb of all isotopes with Z larger than 8 have been obtained. Velocity distributions were also measured. Comparisons to models describing spallation reactions and some empirical formulae often used in astrophysics are presented. These data are directly used to calculate impurety production and DPAs in a thin window as foreseen in spallation sources or accelerator-driven systems
Scavenger receptor BI mediates the selective uptake of oxidized cholesterol esters by rat liver
Biofarmaci
Yeasts and wine off-flavours: a technological perspective
Review article. Part of the special issue "Wine microbiology and safety: from the vineyard to the bottle (Microsafety Wine)", 19-20 Nov. 2009, ItalyIn wine production, yeasts have both beneficial
and detrimental activities. Saccharomyces cerevisiae is the
yeast mainly responsible for turning grape juice into wine
but this species and several others may also show
undesirable effects in wines. Among such effects, technologists
are particularly concerned with the production of offflavours
that may occur during all stages of winemaking.
Typical spoiling activities include the production of ethyl
acetate by apiculate yeasts before fermentation, hydrogen
sulphide by S. cerevisiae during fermentation phases,
acetaldehyde by film-forming yeasts during bulk storage,
and volatile phenols by Dekkera bruxellensis during storage
or after bottling. The occurrence of these hazards depends
on the technological operations designed to obtain a given
type of wine and most can be avoided by current preventive
or curative measures. On the contrary, good manufacturing
practices must be strengthened to deal with the problem of
volatile phenol production in red wines. Appropriate
monitoring of D. bruxellensis populations and quantification
of 4-ethylphenol is advised during storage, particularly
when oak barrels are used, and absence of viable cells must
be guaranteed in bottled wines. This work, which is based
on our experience at winery level, aims to provide
information on appropriate technological strategies to deal
with the problem of off-flavours produced by yeasts
Predicting Transitions in Low and High Levels of Risk Behavior from Early to Middle Adolescence: The TRAILS Study
The present study examined the joint development of substance use and externalizing problems in early and middle adolescence. First, it was tested whether the relevant groups found in previous studies i.e., those with an early onset, a late onset, and no onset or low levels of risk behavior could be identified, while using a developmental model of a single, underlying construct of risk behavior. Second, departing from Moffitt’s taxonomy of antisocial behavior, it was tested if early, but not late, onset risk behavior is predicted by a problematic risk profile in childhood. Data were used from TRAILS, a population based cohort study, starting at age 11 with two follow-ups at mean ages of 13.6 and 16.3 years. Latent transition analyses demonstrated that, both in early and middle adolescence, a single underlying construct of risk behavior, consisting of two classes (labeled as low and high risk behavior), adequately represented the data. Respondents could be clearly classified into four possible transition patterns from early to middle adolescence, with a transition from high to low being almost non-existent (2.5 %), low to low (39.4 %) and low to high (41.8 %) being the most prevalent, and high to high (16.2 %) substantial. As hypothesized, only the high-high group was characterized by a clear adverse predictor profile in late childhood, while the low-high group was not. This study demonstrates that the development of substance use is correlated with externalizing problems and underscores the theory that etiologies of early and later onset risk behavior are different
Occurrence of Cryptosporidial Oocysts and Giardia Cysts in Bottled Mineral Water Commercialized in the City of Campinas, State of São Paulo, Brazil
Does administration of non-steroidal anti-inflammatory drug determine morphological changes in adrenal cortex: ultrastructural studies
Rofecoxib (Vioxx© made by Merck Sharp & Dohme, the USA) is a non-steroidal anti-inflammatory drug which belongs to the group of selective inhibitors of cyclooxygenasis-2, i.e., coxibs. Rofecoxib was first registered in the USA, in May 1999. Since then the drug was received by millions of patients. Drugs of this group were expected to exhibit increased therapeutic action. Additionally, there were expectations concerning possibilities of their application, at least as auxiliary drugs, in neoplastic therpy due to intensifying of apoptosis. In connection with the withdrawal of Vioxx© (rofecoxib) from pharmaceutical market, attempts were made to conduct electron-microscopic evaluation of cortical part of the adrenal gland in preparations obtained from animals under influence of the drug. Every morning animals from the experimental group (15 rats) received rofecoxib (suspension in physiological saline)—non-steroidal anti-inflammatory drug (Vioxx©, Merck Sharp and Dohme, the USA), through an intragastric tube in the dose of 1.25 mg during 8 weeks. In the evaluated material, there was found a greater number of secretory vacuoles and large, containing cholesterol and other lipids as well as generated glucocorticoids, lipid drops in cytoplasm containing prominent endoplasmic reticulum. There were also found cells with cytoplasm of smaller density—especially in apical and basal parts of cells. Mitochondria occasionally demonstrated features of delicate swelling. The observed changes, which occurred on cellular level with application of large doses of the drug, result from mobilization of adaptation mechanisms of the organism
Refúgios artificiais coloridos e o desempenho e sobrevivência de alevinos de Leporinus macrocephalus (Garavello & Britsky, 1988)
Níveis lipêmicos e alguns fatores de risco de doenças cardiovasculares em população do Município de São Paulo, SP (Brasil)
Estrutura e relações ambientais de grupos florísticos em fragmento de floresta estacional subtropical
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