864 resultados para fate and effect modelling


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BACKGROUND: Potential drug-drug interactions (PDDIs) might expand with new combination antiretroviral therapies (ART) and polypharmacy related to increasing age and comorbidities. We investigated the prevalence of comedications and PDDIs within a large HIV cohort, and their effect on ART efficacy and tolerability. METHODS: All medications were prospectively recorded in 1,497 ART-treated patients and screened for PDDIs using a customized version of the Liverpool drug interactions database. RESULTS: Overall, 68% (1,013/1,497) of patients had a comedication and 40% (599/1,497) had > or = 1 PDDI. Among patients with comedication, 2% (21/1,013) had red-flag interactions (contraindicated) and 59% (597/1,013) had orange-flag interactions (potential dose adjustment and/or close monitoring required). The latter involved mainly central nervous system drugs (49%), cardiovascular drugs (34%) and methadone (19%). In the multivariate analysis, factors associated with having a comedication were advanced age, female gender, obesity and HCV infection. Independent risk factors for PDDIs were regimens combining protease inhibitors and non-nucleoside reverse transcriptase inhibitors (odds ratio [OR] 3.06, 95% confidence interval [CI] 1.44-6.48), > or = 2 comedications (OR 1.89, 95% CI 1.32-2.70), current illicit drug use (OR 2.00, 95% CI 1.29-3.10) and patients with HCV infection (OR 1.74, 95% CI 1.19-2.56). Viral response was similar in patients with and without PDDIs (84.5% versus 86.4%; P=0.386). During follow-up, ART was modified in 134 patients with comedication regardless of the presence of PDDIs (P=0.524). CONCLUSIONS: PDDIs increase with complex ART and comorbidities. No adverse effect was noted on ART efficacy or tolerability; however, most PDDIs affected comedication but were manageable through dose adjustment or monitoring.

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This paper focuses on the transformation of French public policy on doping and its effects on the life of cycling professionals. We first focus on the emergence and the evolution of French public policies against doping in cycling. Then the article attempts to qualitatively observe the effects of policies on cyclists. The objective is to understand how the cycling culture is evolving. This article is based on 39 interviews with new and seasoned professionals, as well as ethnographic observations over a dozen years .

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Several factors influence the selection of oviposition substrates by insects. The aim of the present work was to find answers to the following questions related to the oviposition behavior of Anastrepha obliqua. Can carbohydrates (glucose or sucrose) present in the adult diet have influence on the female preference for an oviposition substrate with similar composition? Can the previous experience with a host containing one of mentioned carbohydrates interfere in further selection of oviposition substrates? The results showed that the kind of carbohydrate present in the adult diet did not affect the female preference for an artificial oviposition substrate, neither when it was presented by itself nor in combination with brewer's yeast. The effect of experience in the oviposition behavior was observed when there was a previous contact with artificial oviposition substrates containing yeast and sucrose. The data are discussed in terms of the behavioral plasticity presented by this species in relation to feeding and oviposition behaviors.

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Aim: Fabry disease is an X-linked genetic disorder due to deficiency of the lysosomal enzyme a-galactosidase A, which leads to the accumulation of neutral glycosphingolipids within the lysosomes of almost all tissues. Clinical manifestations usually include acroparaesthesia, renal insufficiency and cardiomyopathy. Recently, pulmonary manifestations consisting of progressive obstructive airway disease have been reported. The aim of this study was to analyse the cross-sectional prevalence of airflow obstruction in a Swiss cohort of patients, and in selected cases, to evaluate the impact of enzyme replacement therapy (ERT) with agalsidase alfa (ReplagalTM; TKT - 5S). Methods: Forty-four patients (27 men, 17 women) were included in the study and received pulmonary function testing. Fifteen patients underwent spirometry after ERT. Results: Twelve patients (nine men) had chronic obstructive pulmonary disease according to the Global Obstructive Lung Disease (GOLD) initiative criteria: forced expiratory volume (FEV1)/forced vital capacity (FVC) 50.7), but only one was an active smoker and one a previous smoker. FEV1/ FVC as percentage predicted was weakly correlated with age (r=0.42, p=0.005, calculated by Pearson product-moment correlation), demonstrating that airway obstruction occurs in the late stages of the disease. Median FEV1 in patients with obstruction was 67% of predicted (range, 45-90%). Reversibility of FEV1 after b2-agonist inhalation never exceeded 8% of predicted. Diffusing capacity of the lung for carbon monoxide (DLCO) was measured in 13 individuals with a median of 88% of predicted (range, 39-125%). After 15+9 months of ERT, spirometry measurements were recorded in 15 patients. Decline in FEV1 was -2+5% of predicted. (p40.05, measured by the Wilcoxon signed-rank test). Median change in DLCO was -10% of predicted (-40 to +25%, p40.05). High resolution computed tomography scans demonstrated a moderate thickening of the bronchial wall in affected individuals, without evidence of emphysema. Conclusion: We conclude that Fabry disease can be complicated by significant airway obstruction, particularly in patients in the advanced stages of the disease, and that in the period studied, ERT had no demonstrable impact on pulmonary function.

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Modern agriculture techniques have a great impact on crops and soil quality, especially by the increased machinery traffic and weight. Several devices have been developed for determining soil properties in the field, aimed at managing compacted areas. Penetrometry is a widely used technique; however, there are several types of penetrometers, which have different action modes that can affect the soil resistance measurement. The objective of this study was to compare the functionality of two penetrometry methods (manual and automated mode) in the field identification of compacted, highly mechanized sugarcane areas, considering the influence of soil water volumetric content (θ) on soil penetration resistance (PR). Three sugarcane fields on a Rhodic Eutrudrox were chosen, under a sequence of harvest systems: one manual harvest (1ManH), one mechanized harvest (1MH) and three mechanized harvests (3MH). The different degrees of mechanization were associated to cumulative compaction processes. An electronic penetrometer was used on PR measurements, so that the rod was introduced into the soil by hand (Manual) and by an electromechanical motor (Auto). The θ was measured in the field with a soil moisture sensor. Results showed an effect of θ on PR measurements and that regression models must be used to correct data before comparing harvesting systems. The rod introduction modes resulted in different mean PR values, where the "Manual" overestimated PR compared to the "Auto" mode at low θ.

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Magnetic properties of Fe nanodots are simulated using a scaling technique and Monte Carlo method, in good agreement with experimental results. For the 20-nm-thick dots with diameters larger than 60¿nm, the magnetization reversal via vortex state is observed. The role of magnetic interaction between dots in arrays in the reversal process is studied as a function of nanometric center-to-center distance. When this distance is more than twice the dot diameter, the interaction can be neglected and the magnetic properties of the entire array are determined by the magnetic configuration of the individual dots. The effect of crystalline anisotropy on the vortex state is investigated. For arrays of noninteracting dots, the anisotropy strongly affects the vortex nucleation field and coercivity, and only slightly affects the vortex annihilation field

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Understanding and anticipating biological invasions can focus either on traits that favour species invasiveness or on features of the receiving communities, habitats or landscapes that promote their invasibility. Here, we address invasibility at the regional scale, testing whether some habitats and landscapes are more invasible than others by fitting models that relate alien plant species richness to various environmental predictors. We use a multi-model information-theoretic approach to assess invasibility by modelling spatial and ecological patterns of alien invasion in landscape mosaics and testing competing hypotheses of environmental factors that may control invasibility. Because invasibility may be mediated by particular characteristics of invasiveness, we classified alien species according to their C-S-R plant strategies. We illustrate this approach with a set of 86 alien species in Northern Portugal. We first focus on predictors influencing species richness and expressing invasibility and then evaluate whether distinct plant strategies respond to the same or different groups of environmental predictors. We confirmed climate as a primary determinant of alien invasions and as a primary environmental gradient determining landscape invasibility. The effects of secondary gradients were detected only when the area was sub-sampled according to predictions based on the primary gradient. Then, multiple predictor types influenced patterns of alien species richness, with some types (landscape composition, topography and fire regime) prevailing over others. Alien species richness responded most strongly to extreme land management regimes, suggesting that intermediate disturbance induces biotic resistance by favouring native species richness. Land-use intensification facilitated alien invasion, whereas conservation areas hosted few invaders, highlighting the importance of ecosystem stability in preventing invasions. Plants with different strategies exhibited different responses to environmental gradients, particularly when the variations of the primary gradient were narrowed by sub-sampling. Such differential responses of plant strategies suggest using distinct control and eradication approaches for different areas and alien plant groups.

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En la investigació de la complexació de metalls mitjançant eines electroanalítiques són emprades dues aproximacions generals. La primera, anomenada de modelatge dur (hardmodelling), es basa en la formulació d'un model fisicoquímic conjunt per als processos electròdic i de complexació i en la resolució analítica o numèrica del model. Posteriorment, l'ajust dels paràmetres del model a les dades experimentals donarà la informació desitjada sobre el procés de complexació. La segona aproximació, anomenada de modelatge tou (soft-modelling), es basa en la identificació d'un model de complexació a partir de l'anàlisi numèrica i estadística de les dades, sense cap assumpció prèvia d'un model. Aquesta aproximació, que ha estat extensivament emprada amb dades espectroscòpiques, ho ha estat poquíssim amb dades electroquímiques. En aquest article tractem de la formulació d'un model (hard-modelling) per a la complexació de metalls en sistemes amb mescles de lligands, incloent-hi lligands macromoleculars, i de l'aplicació d

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Leishmania spp. are intracellular protozoan parasites that are delivered within the dermis of their vertebrate hosts. Within this peripheral tissue and the draining lymph node, they find and/or rapidly create dynamic microenvironments that determine their ultimate fate, namely their more or less successful expansion, and favour their transmission to another vertebrate host though a blood-feeding vector. Depending on their genetic characteristics as well as the genetic make-up of their hosts, once within the dermis Leishmania spp. very rapidly drive and maintain sustained T cell-dependent immune responses that arbitrate their ultimate fate within their hosts. The analysis of the parasitism exerted by Leishmania major in mice of different genetic backgrounds has allowed us to recognize some of the early and late mechanisms driven by this parasite that lead to either uncontrolled or restricted parasitism. Uncontrolled parasitism by Leishmania major characterizing mice from a few inbred strains (e.g. BALB/c) is associated with the expansion of parasite reactive Th2 CD4 lymphocytes and results from their rapid and sustained activity. In contrast, restricted parasitism characteristic of mice from the majority of inbred strains results from the development of a polarized parasite-specific Th1 CD4 response. This murine model of infection has already been and will continue to be particularly instrumental in dissecting the rules controlling the pathway of differentiation of T cells in vivo. In the long run, the understanding of these rules should contribute to the rational development of novel immunotherapeutic interventions against severe infectious diseases.

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Työn tavoitteena oli perehtyä innovaatiojohtamisen ja järjestelmän soveltamiseen prosessiteollisuuden toimintaympäristöön. Kirjallisuuslähteitä apuna käyttäen perehdyttiin liiketoimintaympäristön innovaatiojohtamiselle asettamiin vaatimuksiin ja erilaisiin innovaatiojärjestelmiin. Olennaisena osana innovaatiojohtamiseen liittyy sidosryhmien tarpeiden ja niiden tarjoamien resurssien huomioiminen toiminnassa. Myöskin tuotekehityksen menetelmät ja työkalut ovat omalta osaltaan merkittävässä asemassa toiminnan tehokkuutta arvioitaessa. Innovaatiojärjestelmä tulee sopeuttaa yrityksen toimintoihin ja sen erityispiirteet huomioonottaen siten, että toiminnan johtaminen prosessina tuo yritykselle ja sen sidosryhmille lisäarvoa. Innovaatiojärjestelmän luominen yritykselle on ainayksilöllinen prosessi ja siihen ei ole olemassa yleispätevää menetelmää, joka voitaisiin ottaa käyttöön sellaisenaan. Yritys, jonka liiketoiminta keskittyy kuitupohjaisten pakkausmateriaalien valmistamiseen, joutuu täyttämään toiminnassaan materiaalintoimittajien, omien tuotantoprosessiensa ja asiakkaiden sekä jopa loppukäyttäjien uusille tuotteille luomat odotukset. Innovaatiojohtamista sävyttää toiminnan tulosten suuri epävarmuus ja sen vaativien aineellisten ja henkisten resurssien mittavuus. Innovaatiotoiminnan johtaminen prosessina, käyttäen hyväksi järjestelmämallia, tavoittelee systemaattista ja asetettujen kriteerien täyttämää lähestymistapaa tuotekehityksen ja uusien liiketoimintainnovaatioiden alueella. Kehitetyn mallin tulee palvella monimutkaista liiketoimintaympäristöä, jokatoisaalta perustuu tehokkaaseen massatuotantoon ja toisaalta pyrkii erilaistumaan palvelemalla sekä huomioimalla asiakkaidensa tuotteille asettamat vaatimukset.

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This study was carried out to evaluate the yield, total N content in leaves and must composition of grapes from the Cabernet Sauvignon variety subjected to the application of urea and organic compost. Cabernet Sauvignon grapevines in Rosário do Sul, RS, Brazil, in 2008, 2009 and 2010 were subjected to annual application of 40 kg N ha-1 in the form of organic compost and urea, and compared to unfertilized grapevines. In the 2008/09, 2009/10 and 2010/11 crop seasons, leaves were collected for analysis of total N content. At maturation of the grapes, the yield and quality attributes of the must were evaluated. The application of N sources, especially organic compost, increased the N content in the whole leaf at full flowering. Application of organic compost and urea has little effect on grape yield and does not affect the total nutrient content in the must, nor the enological attributes.

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Dopamine release in the prefrontal cortex plays a critical role in cognitive function such as working memory, attention and planning. Dopamine exerts complex modulation on excitability of pyramidal neurons and interneurons, and regulates excitatory and inhibitory synaptic transmission. Because of the complexity of this modulation, it is difficult to fully comprehend the effect of dopamine on neuronal network activity. In this study, we investigated the effect of dopamine on local high-frequency oscillatory neuronal activity (in β band) in slices of the mouse anterior cingulate cortex (ACC). We found that dopamine enhanced the power of these oscillations induced by kainate and carbachol, but did not affect their peak frequency. Activation of D2R and in a lesser degree D1R increased the oscillation power, while activation of D4R had no effect. These high-frequency oscillations in the ACC relied on both phasic inhibitory and excitatory transmission and functional gap junctions. Thus, dopamine released in the ACC promotes high-frequency synchronized local cortical activity which is known to favor information transfer, fast selection and binding of distributed neuronal responses. Finally, the power of these oscillations was significantly enhanced after degradation of the perineuronal nets (PNNs) enwrapping most parvalbumin interneurons. This study provides new insights for a better understanding of the abnormal prefrontal gamma activity in schizophrenia (SZ) patients who display prefrontal anomalies of both the dopaminergic system and the PNNs.

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This article presents the results of a study of the efficiency of silanation process of calcium phosphate glasses particles and its effect on the bioactivity behavior of glasspoly( methyl methacrylate) (PMMA) composites. Two different calcium phosphate glasses: 44.5CaO-44.5P2O5-11Na2O (BV11) and 44.5CaO-44.5P2O5-6Na2O-5TiO2 (G5) were synthesized and treated with silane coupling agent. The glasses obtained were characterized by Microprobe and BET while the efficiency of silanation process was determined using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS) and Thermal Analysis (DTA and TG)techniques. The content of coupling agent chemically tightly bond to the silanated glasses ascended to 1.69 6 0.02 wt % for BV11sil glass and 0.93 6 0.01 wt % for G5sil glass. The in vitro bioactivity test carried out in Simulated Body Fluid (SBF) revealed certain bioactive performance with the use of both silanated glasses in a 30% (by weight) as filler of the PMMA composites because of a superficial deposition of an apatite-like layer with low content of CO3 22 and HPO4 22 in its structure after soaking for 30 days occurred. VC 2013 Wiley Periodicals,Inc. J Biomed Mater Res Part B: Appl Biomater 00B: 000-000, 2013.

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Rosin is a natural product from pine forests and it is used as a raw material in resinate syntheses. Resinates are polyvalent metal salts of rosin acids and especially Ca- and Ca/Mg- resinates find wide application in the printing ink industry. In this thesis, analytical methods were applied to increase general knowledge of resinate chemistry and the reaction kinetics was studied in order to model the non linear solution viscosity increase during resinate syntheses by the fusion method. Solution viscosity in toluene is an important quality factor for resinates to be used in printing inks. The concept of critical resinate concentration, c crit, was introduced to define an abrupt change in viscosity dependence on resinate concentration in the solution. The concept was then used to explain the non-inear solution viscosity increase during resinate syntheses. A semi empirical model with two estimated parameters was derived for the viscosity increase on the basis of apparent reaction kinetics. The model was used to control the viscosity and to predict the total reaction time of the resinate process. The kinetic data from the complex reaction media was obtained by acid value titration and by FTIR spectroscopic analyses using a conventional calibration method to measure the resinate concentration and the concentration of free rosin acids. A multivariate calibration method was successfully applied to make partial least square (PLS) models for monitoring acid value and solution viscosity in both mid-infrared (MIR) and near infrared (NIR) regions during the syntheses. The calibration models can be used for on line resinate process monitoring. In kinetic studies, two main reaction steps were observed during the syntheses. First a fast irreversible resination reaction occurs at 235 °C and then a slow thermal decarboxylation of rosin acids starts to take place at 265 °C. Rosin oil is formed during the decarboxylation reaction step causing significant mass loss as the rosin oil evaporates from the system while the viscosity increases to the target level. The mass balance of the syntheses was determined based on the resinate concentration increase during the decarboxylation reaction step. A mechanistic study of the decarboxylation reaction was based on the observation that resinate molecules are partly solvated by rosin acids during the syntheses. Different decarboxylation mechanisms were proposed for the free and solvating rosin acids. The deduced kinetic model supported the analytical data of the syntheses in a wide resinate concentration region, over a wide range of viscosity values and at different reaction temperatures. In addition, the application of the kinetic model to the modified resinate syntheses gave a good fit. A novel synthesis method with the addition of decarboxylated rosin (i.e. rosin oil) to the reaction mixture was introduced. The conversion of rosin acid to resinate was increased to the level necessary to obtain the target viscosity for the product at 235 °C. Due to a lower reaction temperature than in traditional fusion synthesis at 265 °C, thermal decarboxylation is avoided. As a consequence, the mass yield of the resinate syntheses can be increased from ca. 70% to almost 100% by recycling the added rosin oil.