998 resultados para basic cation saturation ratio


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This paper employs the Lyapunov direct method for the stability analysis of fractional order linear systems subject to input saturation. A new stability condition based on saturation function is adopted for estimating the domain of attraction via ellipsoid approach. To further improve this estimation, the auxiliary feedback is also supported by the concept of stability region. The advantages of the proposed method are twofold: (1) it is straightforward to handle the problem both in analysis and design because of using Lyapunov method, (2) the estimation leads to less conservative results. A numerical example illustrates the feasibility of the proposed method.

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Listeria monocytogenes, etiological agent of severe human foodborne infection, uses sophisticated mechanisms of entry into host cytoplasm and manipulation of the cellular cytoskeleton, resulting in cell death. The host cells and bacteria interaction may result in cytokine production as Tumor Necrosis Factor (TNF) alpha. Hepatocytes have potential to produce pro-inflammatory cytokines as TNF-alpha when invaded by bacteria. In the present work we showed the behavior of hepatocytes invaded by L. monocytogenes by microscopic analysis, determination of TNF-alpha production by bioassay and analysis of the apoptosis through TUNEL technique. The presence of bacterium, in ratios that ranged from 5 to 50,000 bacteria per cell, induced the rupture of cellular monolayers. We observed the presence of internalized bacteria in the first hour of incubation by electronic microscopy. The levels of TNF-alpha increased from first hour of incubation to sixth hour, ranging from 0 to 3749 pg/mL. After seven and eight hours of incubation non-significant TNF-alpha levels decrease occurred, indicating possible saturation of cellular receptors. Thus, the quantity of TNF-alpha produced by hepatocytes was dependent of the incubation time, as well as of the proportion between bacteria and cells. The apoptosis rate increased in direct form with the incubation time (1 h to 8 + 24 h), ranging from 0 to 43%, as well as with the bacteria : cells ratio. These results show the ability of hepatocyte invasion by non-hemolytic L. monocytogenes, and the main consequences of this phenomenon were the release of TNF-alpha by hepatocytes and the induction of apoptosis. We speculate that hepatocytes use apoptosis induced by TNF-alpha for release bacteria to extracellular medium. This phenomenon may facilitate the bacteria destruction by the immune system.

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Introduction: The 2D:4D digit ratio is sexually-dimorphic, probably due to testosterone action through the perinatal period. We characterize the 2D:4D ratio in newborn (NB) infants, in between the pre- and postnatal surges of testosterone, and relate it to the mother's 2D:4D and to testosterone levels in the amniotic fluid (AF). Subjects and methods: Testosterone was assayed in samples of maternal plasma and AF collected at amniocentesis. Shortly after birth, 106 NBs and their mothers were measured for 2D:4D ratio. Results: NB males had lower mean 2D:4D ratios than females but this dimorphism was significant only for the left hand (males: 0.927; females: 0.950; p=0.004). Mothers who had sons had lower 2D:4D ratios than those who had daughters and the mother's 2D:4D were higher than those of NBs regardless of sex. Both hands of NB females were negatively correlated with AF testosterone and positively correlated with the mother's 2D:4D, but males showed no significant associations. Maternal plasma testosterone also showed a negative weak correlation with NB's digit ratio in both sexes. Conclusions: Sexual dimorphism at birth was only significant for the left hand, in contrast with reports of greater right hand dimorphism, suggesting that postnatal testosterone is determinant for 2D:4D stabilization. The lower 2D:4D ratios in mothers who had sons support claims that hormone levels in parents are influential for determining their children's sex. NB female's digit ratio, but not males', was associated to the level of AF testosterone. The mother's 2D:4D ratios were positively correlated with their daughters' 2D:4D, but the same was not observed for male NBs, suggesting that prenatal testosterone levels in male fetus lead their 2D:4D ratios to stray from their mothers' with high individual variability.

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Cation transporters/channels are key players in a wide range of physiological functions in plants, including cell signaling, osmoregulation, plant nutrition and metal tolerance. The recent identification of genes encoding some of these transport systems has allowed new studies toward further understanding of their integrated roles in plant. This review summarizes recent discoveries regarding the function and regulation of the multiple systems involved in cation transport in plant cells. The role of membrane transport in the uptake, distribution and accumulation of cations in plant tissues, cell types and subcellular compartments is described. We also discuss how the knowledge of inter- and intra-species variation in cation uptake, transport and accumulation as well as the molecular mechanisms responsible for these processes can be used to increase nutrient phytoavailability and nutrients accumulation in the edible tissues of plants. The main trends for future research in the field of biofortification are proposed.

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Introduction: Antibiotics are one of the most common prescribed drugs in the NICU; despite this, studies on its use are scarce. Aim: To assess antibiotics utilization ratio in a medical surgical NICU. Methods: Prospective, observational study. Daily registry of antibiotics given to newborn infants; two periods of two months, 2010; data collected every day after the second medical round. Variables: treated patients, days on antibiotics, treatment/patient days, number of courses, number of antibiotics. Antibiotics utilization ratioratio days on antibiotics/days at the NICU. Results: Patients enrolled - 113; admission days – 1722; length of stay - 15.2 days; 85 newborn infants were given antibiotics; days on antibiotics - 771; antibiotics utilization ratio – 44.8; 292 antibiotics were prescribed; 61.8% of patients were given more than two antibiotics and 15.3% had more than one course. The most frequents were gentamicin, cefotaxime, ampicillin, vancomycin and metronidazole. Conclusion: Antibiotics utilization ratio should be subject of audits and a quality criteria on NICUs evaluation.

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Speech interfaces for Assistive Technologies are not common and are usually replaced by others. The market they are targeting is not considered attractive and speech technologies are still not well spread. Industry still thinks they present some performance risks, especially Speech Recognition systems. As speech is the most elemental and natural way for communication, it has strong potential for enhancing inclusion and quality of life for broader groups of users with special needs, such as people with cerebral palsy and elderly staying at their homes. This work is a position paper in which the authors argue for the need to make speech become the basic interface in assistive technologies. Among the main arguments, we can state: speech is the easiest way to interact with machines; there is a growing market for embedded speech in assistive technologies, since the number of disabled and elderly people is expanding; speech technology is already mature to be used but needs adaptation to people with special needs; there is still a lot of R&D to be done in this area, especially when thinking about the Portuguese market. The main challenges are presented and future directions are proposed.

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The aim of the present work was to determine the prevalence of IgG and IgM anti-Toxoplasma gondii antibodies and the factors associated to the infection in pregnant women attended in Basic Health Units in Rolândia, Paraná, Brazil. The sample was divided in two groups: group I (320 pregnant women who were analyzed from July 2007 to February 2008) and group II (287 pregnant women who were analyzed from March to October 2008). In group I, it was found 53.1% of pregnant women with IgG reactive and IgM non-reactive, 1.9% with IgG and IgM reactive, 0.3% with IgG non-reactive and IgM reactive and 44.7% with IgG and IgM non-reactive. In group II, it was found 55.1% with IgG reactive and IgM non-reactive and 44.9% with IgG and IgM non-reactive. The variables associated to the presence of IgG antibodies were: residence in rural areas, pregnant women between 35-40 years old, low educational level, low family income, more than one pregnancy, drinking water which does not originate from the public water supply system and the habit of handling soil or sand. Guidance on primary prevention measures and the quarterly serological monitoring of the pregnant women in the risk group are important measures to prevent congenital toxoplasmosis.

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OBJECTIVE: Arthropathy that mimics osteoarthritis (OA) and osteoporosis (OP) is considered a complication of hereditary hemochromatosis (HH). We have limited data comparing OA and OP prevalence among HH patients with different hemochromatosis type 1 (HFE) genotypes. We investigated the prevalence of OA and OP in patients with HH by C282Y homozygosity and compound heterozygosity (C282Y/H63D) genotype. METHODS: A total of 306 patients with HH completed a questionnaire. Clinical and demographic characteristics and presence of OA, OP and related complications were compared by genotype, adjusting for age, sex, body mass index (BMI), current smoking and menopausal status. RESULTS: In total, 266 of the 306 patients (87%) were homozygous for C282Y, and 40 (13%) were compound heterozygous. The 2 groups did not differ by median age [60 (interquartile range [IQR] 53 to 68) vs. 61 (55 to 67) years, P=0.8], sex (female: 48.8% vs. 37.5%, P=0.18) or current smoking habits (12.4% vs. 10%, P=0.3). As compared with compound heterozygous patients, C282Y homozygous patients had higher median serum ferritin concentration at diagnosis [1090 (IQR 610 to 2210) vs. 603 (362 to 950) µg/L, P<0.001], higher median transferrin saturation [80% (IQR 66 to 91%) vs. 63% (55 to 72%), P<0.001]) and lower median BMI [24.8 (22.1 to 26.9) vs. 26.2 (23.5 to 30.3) kg/m2, P<0.003]. The overall prevalence of self-reported OA was significantly higher with C282Y homozygosity than compound heterozygosity (53.4% vs. 32.5%; adjusted odds ratio [aOR] 2.4 [95% confidence interval 1.2-5.0]), as was self-reported OP (25.6% vs. 7.5%; aOR 3.5 [1.1-12.1]). CONCLUSION: Patients with C282Y homozygosity may be at increased risk of musculoskeletal complications of HH.

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Four years after the first visit seventeen public health units were visited again and evaluated as to standards of storage recommended by the Brazilian Immunization Programme. In 100% of the units, refrigerators and proper inside location of vaccines in the refrigerator were adequatety or regularfy maintained and checked, respectively. However, when control of temperature was checked, onfy 64.7% presented adequate storage conditions. In 94.1 % of the units, health workers complained of lack of immediate technical support in emergency situations. In 55.2 % the titers vaccine samples of were under the minimal recommended potency. It is necessary that the factors concerning the cold chain be continualfy evaluated so that the quality of the vaccines that will be used is not affected.

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Cement & Concrete Composites 45 (2014) 264–271

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Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ensino da Filosofia no Ensino Secundário

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The present essay focuses on the effectiveness of Portuguese public schools’ provision of 7th, 8th and 9th grades, using data from the Portuguese Ministry of Education and Science for 2009/10, 2010/11 and 2011/12. At least two school types offer these grades: Basic and Secondary. Based on previous findings, a production function is estimated for 9th grade students in the regular academic track, including a variable that indicates the specific school type attended by each student. After concluding that Basic Schools add more value, some explanations are presented as well as recommendations and possible further research.

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The main objective of this work is the valorization of residues from agro-industry giving them an added value. The valorization was performed by using a "green" and sustainable solvent - supercritical fluid, in this case carbon dioxide. Two residues and one biomass were used to produce two different final products, thereby emphasizing the versatility of the waste recovery - spent coffee grounds and microalgae Chlorella protothecoides to produce biodiesel, and tomato pomace to extract carotenoids. In the first part of this work it was demonstrated the possibility to obtain a conversion of coffee spent grounds oil into biodiesel, through an enzymatic transesterification reaction, of 98.01% with the following operating conditions: molar ratio oil:methanol 1:24, residence time 0.8 min, pressure 25 MPa, temperature 313,15K. In this first phase, it was also used the microalgae Chlorella protothecoides, a biomass, to produce biodiesel and favorable results were obtained with this green process compared with a traditional process - basic catalysis / acid. In the second part of this work, by an extraction with supercritical CO2 it was obtained 3.38% oil from tomato pomace under the following conditions: pressure 35.1 MPa, temperature 313,15K. It was found that this oil contains various carotenoids: β-carotene, lutein and lycopene. The latter is present in larger amount.

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This work analyses how the leverage ratio behaves through the cycle, vis-à-vis other capital ratios. For a sample of the largest Portuguese banks, the Basel III leverage ratio is indeed countercyclical. This result is relevant from a regulatory perspective, since the introduction of a limit on the leverage ratio will function as a restriction in the banks’ balance sheet size, reducing the economic costs associated with the excessive growth of leverage in periods of economic expansion followed by aggressive deleveraging in the downturn. However, one cannot exclude that restrictions on banks’ leverage incentivize its transference to less regulated intermediaries.