Yarrowia lipolytica : an industrial workhorse

Yarrowia lipolytica is one of the most extensively studied ‘‘non-conventional’’ yeasts, being a strictly aerobic microorganism capable of producing important metabolites and having an intense secretory activity, which justifies efforts to use it in industry (as a biocatalyst), in molecular biology and in genetics studies. Moreover, Y. lipolytica has been considered an adequate model for dimorphism studies in yeasts. Yarrowia lipolytica presents the ability to grow on Olive Mill Wastewater (OMW) as well as to degradate organic compounds, including aliphatic and aromatic hydrocarbons, often accompanied by biosurfactants production. One of the most important products secreted by this microorganism is lipase which can be exploited for several applications in the detergent, food, pharmaceutical, and environmental industries. In addition, Y. lipolytica is able to produce citric acid and aroma from a variety of carbon sources, including sugars, alkanes, plant oils, starch hydrolysates, ethanol, and glycerol. Thus, this chapter presents an overview of Yarrowia lipolytica features and its major biotechnological applications

Attractive Casimir effect in an infrared modified gluon bag model

In this work, we are motivated by previous attempts to derive the vacuum contribution to the bag energy in terms of familiar Casimir energy calculations for spherical geometries. A simple infrared modified model is introduced which allows studying the effects of the analytic structure as well as the geometry in a clear manner. In this context, we show that if a class of infrared vanishing effective gluon propagators is considered, then the renormalized vacuum energy for a spherical bag is attractive, as required by the bag model to adjust hadron spectroscopy.Comment: 7 pages. 1 figure. Accepted for publication in Physical Review D. Revised version with improved analysis and presentation, references adde

Extended-release niacin increases anti-apolipoprotein A-I antibodies that block the antioxidant effect of high-density lipoprotein-cholesterol: the EXPLORE clinical trial.

Extended-release niacin (ERN) is the most effective agent for increasing high-density lipoprotein-cholesterol (HDL-C). Having previously identified anti-HDL antibodies, we investigated whether ERN affected the antioxidant capacity of HDL and whether ERN was associated with the production of antibodies against HDL (aHDL) and apolipoprotein A-I (aApoA-I). METHODS: Twenty-one patients older than 18 years, with HDL-C ≤40 mg dl-1 (men) or ≤50 mg dl-1 (women) were randomly assigned to receive daily ERN (n = 10) or placebo (n = 11) for two sequential 12-week periods, with 4 weeks of wash-out before cross-over. Primary outcome was change of paraoxonase-1 (PON1) activity and secondary outcomes were changes in aHDL and aApoA-I antibodies. Clinical Trial Unique Identifier: EudraCT 2006-006889-42. RESULTS: The effect of ERN on PON1 activity was nonsignificant (coefficient estimate 20.83 U l-1 , 95% confidence interval [CI] -9.88 to 51.53; P = 0.184). ERN was associated with an increase in HDL-C levels (coefficient estimate 5.21 mg dl-1 , 95% CI 1.16 to 9.25; P = 0.012) and its subclasses HDL2 (coefficient estimate 2.46 mg dl-1 , 95% CI 0.57 to 4.34; P = 0.011) and HDL3 (coefficient estimate 2.73 mg dl-1 , 95% CI 0.47 to 4.98; P = 0.018). ERN was significantly associated with the production of aApoA-I antibodies (coefficient estimate 0.25 μg ml-1 , 95% CI 0.09-0.40; P = 0.001). aApoA-I titres at baseline were correlated with decreased PON activity. CONCLUSIONS: The rise in HDL-C achieved with ERN was not matched by improved antioxidant capacity, eventually hampered by the emergence of aApoA-I antibodies. These results may explain why Niacin and other lipid lowering agents fail to reduce cardiovascular risk.info:eu-repo/semantics/publishedVersio

Stories of young dropouts: a social survey of success and failure

info:eu-repo/semantics/publishedVersio

Touros melhoradores ou inseminação artificial: um exercício de avaliação econômica.

A pecuária de corte é uma atividade complexa, que envolve um grande número de variáveis. Dentre as decissões a tomar, destacam-se aquelas ligadas à área de reprodução, começando com a escolha entre monta natural e inseminação artificial. Por seu turno, diversas opções estão disponíveis em cada um desses processos. Quanto à monta natural, é preciso definir a qualidade e, consequentemente, o preço a pagar pelos touros. Na opção por inseminação, há alternativas quanto ao valor genético e preço do sêmen, além da possibilidade de realizar a sincronização de cio das fêmeas. Este trabalho discute os aspectos econômicos da decisão relacionada com o uso de monta natural ou inseminação artificial, bem como analisa o impacto no sistema de produção de variáveis, como preço de touro e de sêmen a taxa de prenhez. Qualquer que seja a escolha, ressalta-se a necessidade de ser feita em absoluta sintonia com os objetivos do sistema de produção.bitstream/item/131362/1/touros-melhoradores-ou-inseminacao-artificial.pd