4,819 research outputs found

    State space exploration in Markov Models

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    Performance and dependability analysis is usually based on Markov models. One of the main problems faced by the analyst is the large state space cardinality of the Markov chain associated with the model, which precludes not only the model solution, but also the generation of the transition rate matrix. However, in many real system models, most of the probability mass is concentred in a small number of states in comparison with the whole state space. Therefore, performability measures may be accurately evaluated from these "high probable" states. In this paper, we present as algorithm to generate the most probable state the is more efficient than previous algorithms in the literature. We also address the problem of calculating measures of interest and show how bounds on some measures can b efficiently calculated.Análise de desempenho e dependabilidade baseia-se usualmente em modelos Markovianos. Um dos principais problemas que o analista encontra é a grande cardinalidade do espaço de estados da cadeias de Markov associada ao modelo, o que impede não somente a solução do modelo, mas também a geração da matriz de transição de estados. Entretanto, em muitos modelos de sistemas reais, a maioria da massa de probabilidade está concentrada em um pequeno número de estados em comparação com a totalidade do espaço dos estados. Por conseguinte, medidas de desempenhabilidade ('performability') podem ser avaliadas com precisão a partir desses estados mais prováveis. Neste artigo, apresentamos um algoritmo de geração dos estados mais prováveis que é mais eficiente que algoritmos anteriormente propostos na literatura. Abordaremos também o problema de cálculo das medidas de interesse e mostraremos como limites para algumas medidas podem ser eficientemente calculados

    Caffeine, but not other phytochemicals, in mate tea (Ilex paraguariensis St. Hilaire) attenuates high-fat-high-sucrose-diet-driven lipogenesis and body fat accumulation

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    Authors followed the guidelines of the National Institutes of Health guide for the care and use of Laboratory animals (NIH Publications No.8023, revised 1978)The objective was to examine the effectiveness of mate tea (MT, Ilex paraguariensis St. Hilaire) and caffeine from mate tea (MC) on in vitro lipid accumulation and in vivo diet-driven-obesity. MC and decaffeinated mate (DM) were obtained using supercritical CO2 extraction and mainly composed of caffeine and caffeoylquinic acids, respectively. MC reduced lipid accumulation (41%) via downregulation of fatty acid synthase (Fasn) (39%) in 3T3-L1 adipocytes. Rats fed a high-fat-high-sucrose-diet and 0.1% of caffeine from MC, MT, or DM. MC attenuated weight gain (16%) and body fat accumulation (22%). MC reduced Fasn expression in both adipose tissue (66%) and liver (37%). MC diminished pyruvate kinase (PK, 59%) and microsomal triglyceride transfer protein (MTP, 50%) hepatic expression. In silico, neochlorogenic acid interacted with PK and MTP allosteric sites. FAS β‐ketoacyl reductase domain showed the highest affinity to 3,5-dicaffeoylquinic acid. Caffeine suppressed lipid accumulation and body weight gain, through the modulation of lipogenic gene expressio

    Scalable quantum dot based optical interconnects

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    Scalable quantum dot based optical switches offer energy-efficient low-latency data routing. Low power penalty routing over multiple stages are feasible with with the prospect of larger scale photonic integration

    Scalable Purification and Characterization of the Anticancer Lunasin Peptide from Soybean

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    Lunasin is a peptide derived from the soybean 2S albumin seed protein that has both anticancer and anti-inflammatory activities. Large-scale animal studies and human clinical trials to determine the efficacy of lunasin in vivo have been hampered by the cost of synthetic lunasin and the lack of a method for obtaining gram quantities of highly purified lunasin from plant sources. The goal of this study was to develop a large-scale method to generate highly purified lunasin from defatted soy flour. A scalable method was developed that utilizes the sequential application of anion-exchange chromatography, ultrafiltration, and reversed-phase chromatography. This method generates lunasin preparations of >99% purity with a yield of 442 mg/kg defatted soy flour. Mass spectrometry of the purified lunasin revealed that the peptide is 44 amino acids in length and represents the original published sequence of lunasin with an additional C-terminal asparagine residue. Histone-binding assays demonstrated that the biological activity of the purified lunasin was similar to that of synthetic lunasin. This study provides a robust method for purifying commercial-scale quantities of biologically-active lunasin and clearly identifies the predominant form of lunasin in soy flour. This method will greatly facilitate the development of lunasin as a potential nutraceutical or therapeutic anticancer agent

    Cellular proliferation rate and insulin-like growth factor binding protein (IGFBP)-2 and IGFBP-3 and estradiol receptor alpha expression in the mammary gland of dairy heifers naturally infected with gastrointestinal nematodes during development

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    Mammary ductal morphogenesis during prepuberty occurs mainly in response to insulin-like growth factor-1 (IGF-1) and estradiol stimulation. Dairy heifers infected with gastrointestinal nematodes have reduced IGF-1 levels, accompanied by reduced growth rate, delayed puberty onset, and lower parenchyma-stroma relationship in their mammary glands. Immunohistochemical studies were undertaken to determine variations in cell division rate, IGF-1 system components, and estradiol receptors (ESR) during peripubertal development in the mammary glands of antiparasitic-treated and untreated Holstein heifers naturally infected with gastrointestinal nematodes. Mammary biopsies were taken at 20, 30, 40, and 70 wk of age. Proliferating cell nuclear antigen immunolabeling, evident in nuclei, tended to be higher in the parenchyma of the glands from treated heifers than in those from untreated. Insulin-like growth factor binding proteins (IGFBP) type 2 and type 3 immunolabeling was cytoplasmic and was evident in stroma and parenchyma. The IGFBP2-labeled area was lower in treated than in untreated heifers. In the treated group, a maximal expression of this protein was seen at 40 wk of age, whereas in the untreated group the labeling remained constant. No differences were observed for IGFBP3 between treatment groups or during development. Immunolabeling for α ESR (ESR1) was evident in parenchymal nuclei and was higher in treated than in untreated heifers. In the treated group, ESR1 peaked at 30 wk of age and then decreased. These results demonstrate that the parasite burden in young heifers negatively influence mammary gland development, affecting cell division rate and parameters related to estradiol and IGF-1 signaling in the gland.Escuela de Agricultura y Ganadería "María Cruz y Manuel L. Inchausti

    Cellular proliferation rate and insulin-like growth factor binding protein (IGFBP)-2 and IGFBP-3 and estradiol receptor alpha expression in the mammary gland of dairy heifers naturally infected with gastrointestinal nematodes during development

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    Mammary ductal morphogenesis during prepuberty occurs mainly in response to insulin-like growth factor-1 (IGF-1) and estradiol stimulation. Dairy heifers infected with gastrointestinal nematodes have reduced IGF-1 levels, accompanied by reduced growth rate, delayed puberty onset, and lower parenchyma-stroma relationship in their mammary glands. Immunohistochemical studies were undertaken to determine variations in cell division rate, IGF-1 system components, and estradiol receptors (ESR) during peripubertal development in the mammary glands of antiparasitic-treated and untreated Holstein heifers naturally infected with gastrointestinal nematodes. Mammary biopsies were taken at 20, 30, 40, and 70 wk of age. Proliferating cell nuclear antigen immunolabeling, evident in nuclei, tended to be higher in the parenchyma of the glands from treated heifers than in those from untreated. Insulin-like growth factor binding proteins (IGFBP) type 2 and type 3 immunolabeling was cytoplasmic and was evident in stroma and parenchyma. The IGFBP2-labeled area was lower in treated than in untreated heifers. In the treated group, a maximal expression of this protein was seen at 40 wk of age, whereas in the untreated group the labeling remained constant. No differences were observed for IGFBP3 between treatment groups or during development. Immunolabeling for α ESR (ESR1) was evident in parenchymal nuclei and was higher in treated than in untreated heifers. In the treated group, ESR1 peaked at 30 wk of age and then decreased. These results demonstrate that the parasite burden in young heifers negatively influence mammary gland development, affecting cell division rate and parameters related to estradiol and IGF-1 signaling in the gland.Escuela de Agricultura y Ganadería "María Cruz y Manuel L. Inchausti

    Perception, prevalence and factors associated to school bullying in young people from a population affiliated in a colombian health subsidized insurance company in 2018.

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    Describe the perception from young people about bullying, the prevalence of this event and explore the factors associated with being a victim. A retrospective cohort (2014-2018) was followed by a health insurer company of the subsidized regime in Colombia. The study sample consisted of 35,214 young people aged 10-24 years living in 21 municipalities of the Colombian Caribbean region. Means and standard deviation were expressed for continuous variables and frequencies for categorical variables. For the associated factors, a logistic model was estimated using as explanatory variables, sex, housing area, age range, family functionality, disability of the young person, disability of a family member and variables of psychological perception. 63.6% of young people answered that they have knowledge about what school bullying is, noting that as the schooling of the young person increases, the higher the proportion of positive response. The physical or verbal school bullying rate was 94 young people per 1,000. It was found that factors such as the youth feeling useless and guilty (OR = 3.14, p = 0.000), attending psychological counseling (OR = 1.78, p = 0.000), repeating years (OR = 1.49, p = 0.000), that the young person has a disability (OR = 1.33, p = 0.004), or a family member has a disability (OR = 1.27, p = 0.000), is associated with being a victim of bullying. Likewise, it was found that belonging to a highly functional family environment (OR = 0.57, p = 0.000) is a protective factor. School bullying is an event that needs attention and requires supervision of all those around young people, in order to avoid changes in behavior or suicide. Therefore, health systems must offer comprehensive care to prevent mental health risks related to bullying given their relationship with the presence of disability of the young person or a relativ

    Sexual behavior, use of contraceptive methods and pregnancy in young people from a population affiliated in a health insurer company in Colombia 2018

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    Describe the average age of sexual life onset from young people and adolescents, the prevalence of contraceptive methods and explore determinants of pregnancy. A retrospective cohort (2014-2018) was followed by a health insurer of the subsidized regime in Colombia. The study sample consisted of 35,214 young people aged 10-24 years living in 21 municipalities of the Colombian Caribbean region. For the social determinants of pregnancy, a multivariate probit model was estimated using as explanatory variables, housing area, education, family functionality and sexual behavior. 10.3% of women and 14.1% of men had their first sexual encounter before age 14 and 43.5% of women and 37.4% of men began their sex life after age 17. From the young people who claimed to have started their sexual life, 70.9% of the men made use of the condom as a contraceptive method, while the women divided on average 27.2% for the pills and / or injections followed by 16 , 1% in the use of the subdermal implant. As determinants of pregnancy in young people under 20, it was found that variables such as suspending school years [Yes (β = 0.6, p = 0.006)], being planned with hormonal method [Yes (β = 0.5, p = 0.000)] or start sexual life [Between 10 to 14 years (β = 0.14, p = 0.000)], increase the likelihood of young women becoming pregnant at some time in their life. These results also showed that the schooling of the young [University (β = -0.4, p = 0.038)] and always use condoms in sexual intercourse [Yes (β = -0.5, p = 0.042)] help prevent the pregnancy event from occurring. The age of sexual onset establishes a basis on which decision makers should intervene for promote a safe sex life, from use of anticonceptives in young people and thus avoiding unplanned pregnancy

    Rural congestive heart failure mortality among US elderly, 1999–2013: Identifying counties with promising outcomes and opportunities for implementation research

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    Objective Describe modern trends in congestive heart failure (CHF) among elderly (\u3e65 years of age) in the United States, to identify potentially successful rural areas. Compare CHF mortality using multiple- (MCOD) versus underlying-(UCOD) cause of death data. Methods U.S. Centers for Disease Control and Prevention mortality files (WONDER internet site). Results Using MCOD data, overall mortality rates/100,000 population (and 95% confidence intervals) for CHF among persons \u3e65 years of age (1999–2013) were 482.0 (481.2–482.8) for large central and large fringe metropolitan (LCLF) counties, 549.6 (548.6–550.7) in small and medium metropolitan (SM) counties, and 652.6 (650.9–654.0) in micropolitan and non-core, non-metropolitan (MNCNM) counties. Twenty positive deviance NCNM counties (collectively including 198,581 residents \u3e65 years of age) had an overall CHF rate of 300.9 (275.0–326.9) in 2013. This was significantly lower than the LCLF rate for 2013 (482.0 [481.2–482.8]), and represented a reduction of 47% since 1999. Overall CHF occurrence as estimated with MCOD was 3.4-fold higher than that obtained with UCOD. Conclusion These data illustrate underestimation of CHF by UCOD data and the importance of correct death certification. Rural CHF mortality rates are higher than urban rates, but some positive deviance counties demonstrate that this is not inevitable. Further research is needed to understand the relative contribution of research innovation, medical care, and public health to rural-urban disparities and the relative success of positive deviance counties
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