3,214 research outputs found

    Statistical Laws Governing Fluctuations in Word Use from Word Birth to Word Death

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    We analyze the dynamic properties of 10^7 words recorded in English, Spanish and Hebrew over the period 1800--2008 in order to gain insight into the coevolution of language and culture. We report language independent patterns useful as benchmarks for theoretical models of language evolution. A significantly decreasing (increasing) trend in the birth (death) rate of words indicates a recent shift in the selection laws governing word use. For new words, we observe a peak in the growth-rate fluctuations around 40 years after introduction, consistent with the typical entry time into standard dictionaries and the human generational timescale. Pronounced changes in the dynamics of language during periods of war shows that word correlations, occurring across time and between words, are largely influenced by coevolutionary social, technological, and political factors. We quantify cultural memory by analyzing the long-term correlations in the use of individual words using detrended fluctuation analysis.Comment: Version 1: 31 pages, 17 figures, 3 tables. Version 2 is streamlined, eliminates substantial material and incorporates referee comments: 19 pages, 14 figures, 3 table

    Exploring the Free Energy Landscape: From Dynamics to Networks and Back

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    The knowledge of the Free Energy Landscape topology is the essential key to understand many biochemical processes. The determination of the conformers of a protein and their basins of attraction takes a central role for studying molecular isomerization reactions. In this work, we present a novel framework to unveil the features of a Free Energy Landscape answering questions such as how many meta-stable conformers are, how the hierarchical relationship among them is, or what the structure and kinetics of the transition paths are. Exploring the landscape by molecular dynamics simulations, the microscopic data of the trajectory are encoded into a Conformational Markov Network. The structure of this graph reveals the regions of the conformational space corresponding to the basins of attraction. In addition, handling the Conformational Markov Network, relevant kinetic magnitudes as dwell times or rate constants, and the hierarchical relationship among basins, complete the global picture of the landscape. We show the power of the analysis studying a toy model of a funnel-like potential and computing efficiently the conformers of a short peptide, the dialanine, paving the way to a systematic study of the Free Energy Landscape in large peptides.Comment: PLoS Computational Biology (in press

    Insulin resistance in adolescents with Down syndrome: a cross-sectional study

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    BACKGROUND: The prevalence of diabetes mellitus is higher in individuals with Down syndrome (DS) than in the general population; it may be due to the high prevalence of obesity presented by many of them. The aim of this study was to evaluate the insulin resistance (IR) using the HOMA (Homeostasis Model Assessment) method, in DS adolescents, describing it according to the sex, body mass index (BMI) and pubertal development. METHODS: 15 adolescents with DS (8 males and 7 females) were studied, aged 10 to 18 years, without history of disease or use of medication that could change the suggested laboratory evaluation. On physical examination, the pubertal signs, acanthosis nigricans (AN), weight and height were evaluated. Fasting plasma glucose and insulin were analysed by the colorimetric method and RIA-kit LINCO, respectively. IR was calculated using the HOMA method. The patients were grouped into obese, overweight and normal, according to their BMI percentiles. The EPIINFO 2004 software was used to calculate the BMI, its percentile and Z score. RESULTS: Five patients were adults (Tanner V or presence of menarche), 9 pubertal (Tanner II – IV) and 1 prepubertal (Tanner I). No one had AN. Two were obese, 4 overweight and 9 normal. Considering the total number of patients, HOMA was 1.7 ± 1.0, insulin 9.3 ± 4.8 μU/ml and glucose 74.4 ± 14.8 mg/dl. The HOMA values were 2.0 ± 1.0 in females and 1.5 ± 1.0 in males. Considering the nutritional classification, the values of HOMA and insulin were: HOMA: 3.3 ± 0.6, 2.0 ± 1.1 and 1.3 ± 0.6, and insulin: 18.15 ± 1.6 μU/ml, 10.3 ± 3.5 μU/ml and 6.8 ± 2.8 μU/ml, in the obese, overweight and normal groups respectively. Considering puberty, the values of HOMA and insulin were: HOMA: 2.5 ± 1.3, 1.4 ± 0.6 and 0.8 ± 0.0, and insulin: 13.0 ± 5.8 μU/ml, 7.8 ± 2.9 μU/ml and 4.0 ± 0.0 μU/ml, in the adult, pubertal and prepubertal groups respectively. CONCLUSION: The obese and overweight, female and adult patients showed the highest values of HOMA and insulin

    Briquetagem da biomassa do capim-elefante variedade Madeira com diferentes granulometrias de partículas.

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    bitstream/item/220905/1/COT-238-20-FinalAnderson-v1-1.pd

    Tecnologias na promoção da saúde de idosos com doenças crônicas na Atenção Primária à Saúde

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    Aim: to know the technology adopted by nurses in health promotion for elderly people with chronic diseases in Primary Health Care. Method: this is an exploratory research, with qualitative and descriptive approach, held at Cariri, south of Ceará, Brazil. Nurses who adopt technologies for the older adults with chronic were included. Semi-structured interview was used for data collection during July and August 2014, using thematic content analysis. Results: from the analysis, two categories emerged: Technologies used in health promotion of elderly people with chronic diseases and Strategies for the use of technologies in the elderly group in Primary Health Care. Light technologies stood out (humanized host and bond) and hard (glucose meter, tensiometer among others). They were chosen for health promotion activities by professionals. Conclusion: there is no clarity on the concept of health technologies, especially in the use of soft-hard technologiesObjetivo: conocer la tecnología empleada por las enfermeras en la promoción de la salud para ancianos con enfermedades crónicas en la Atención Primaria de Salud. Método: investigación exploratoria, cualitativa y descriptiva, realizada en Cariri, ciudad del sur de Ceará, Brasil. Se incluyó enfermeras de atención primaria que emplean tecnologías para ancianos con enfermedades crónicas. Fue utilizada para la recolección de datos una entrevista semi-estructurada realizada entre julio y agosto 2014. Resultados: a partir del análisis de las categorías surgieron: tecnologías empleadas en la salud para ancianos con enfermedades crónicas y estrategias para el empleo de tecnologías para ancianos en la Atención Primaria de Salud. Se destacaron las tecnologías leves (anfitrión humanizado y bonos) y severas (medidor de glucosa, tensiómetro y otros) que fueron elegidas para actividades de promoción de la salud por los profesionales. Conclusión: no hay claridad sobre el concepto de tecnologías de la salud, especialmente en el uso de blandas-duras.http://dx.doi.org/10.5902/2179769217160Objetivo: conhecer as tecnologias empregadas pelos enfermeiros na promoção da saúde de idosos com doenças crônicas na Atenção Primária à Saúde. Método: pesquisa exploratória, com abordagem qualitativa e de caráter descritivo, realizada em uma cidade da região do Cariri, sul do Ceará, Brasil. Foram incluídos os enfermeiros da atenção primária que empregavam tecnologias para idosos com doença crônica. Utilizou-se entrevista semiestruturada para coleta de dados nos meses de julho e agosto de 2014, com análise de conteúdo temático. Resultados: emergiram duas categorias: Tecnologias empregadas na promoção da saúde de idosos com doenças crônicas e Estratégias para emprego de tecnologias no grupo de idosos na Atenção Primária à Saúde. Destacaram-se as tecnologias leves (acolhimento humanizado e vínculo) e duras (glicosímetro, tensiômetro e outras), que foram escolhidas pelos profissionais para as atividades de promoção da saúde. Conclusão: não existe clareza no conceito de tecnologias de saúde, especialmente no emprego das tecnologias leve-duras

    Impact of gestational weight gain on obstetric and neonatal outcomes in obese diabetic women

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    Both obesity and gestational diabetes mellitus are increasing in prevalence, being a major health problem in pregnancy with independent and additive impact on obstetrics outcomes. It is recognized that inadequate gestational weight gain is an independent risk factor for pregnancy-related morbidity. The aim of this study was to evaluate the effect of gestational weight gain on obstetric and neonatal outcomes in obese women with gestational diabetes

    Segmental and total uniparental isodisomy (UPiD) as a disease mechanism in autosomal recessive lysosomal disorders : evidence from SNP arrays

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    Analyses in our diagnostic DNA laboratory include genes involved in autosomal recessive (AR) lysosomal storage disorders such as glycogenosis type II (Pompe disease) and mucopolysaccharidosis type I (MPSI, Hurler disease). We encountered 4 cases with apparent homozygosity for a disease-causing sequence variant that could be traced to one parent only. In addition, in a young child with cardiomyopathy, in the absence of other symptoms, a diagnosis of Pompe disease was considered. Remarkably, he presented with different enzymatic and genotypic features between leukocytes and skin fibroblasts. All cases were examined with microsatellite markers and SNP genotyping arrays. We identified one case of total uniparental disomy (UPD) of chromosome 17 leading to Pompe disease and three cases of segmental uniparental isodisomy (UPiD) causing Hurler-(4p) or Pompe disease (17q). One Pompe patient with unusual combinations of features was shown to have a mosaic segmental UPiD of chromosome 17q. The chromosome 17 UPD cases amount to 11% of our diagnostic cohort of homozygous Pompe patients (plus one case of pseudoheterozygosity) where segregation analysis was possible. We conclude that inclusion of parental DNA is mandatory for reliable DNA diagnostics. Mild or unusual phenotypes of AR diseases should alert physicians to the possibility of mosaic segmental UPiD. SNP genotyping arrays are used in diagnostic workup of patients with developmental delay. Our results show that even small Regions of Homozygosity that include telomeric areas are worth reporting, regardless of the imprinting status of the chromosome, as they might indicate segmental UPiD.Peer reviewe

    Protein-coding and non-coding gene expression analysis in differentiating human keratinocytes using a three-dimensional epidermal equivalent

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    The epidermal compartment is complex and organized into several strata composed of keratinocytes (KCs), including basal, spinous, granular, and corniWed layers. The continuous process of self-renewal and barrier formation is dependent on a homeostatic balance achieved amongst KCs involving proliferation, diVerentiation, and cell death. To determine genes responsible for initiating and maintaining a corniWed epidermis, organotypic cultures comprised entirely of stratiWed KCs creating epidermal equivalents (EE) were raised from a submerged state to an air/liquid (A/L) interface. Compared to the array proWle of submerged cultures containing KCs predominantly in a proliferative (relatively undiVerentiated) state, EEs raised to an A/L interface displayed a remarkably consistent and distinct proWle of mRNAs. Cultures lifted to an A/L interface triggered the induction of gene groups that regulate proliferation, diVerentiation, and cell death. Next, diVerentially expressed microRNAs (miRNAs) and long noncoding (lncRNA) RNAs were identiWed in EEs. Several diVerentially expressed miRNAs were validated by qRT-PCR and Northern blots. miRNAs 203, 205 and Let-7b were up-regulated at early time points (6, 18 and 24 h) but downregulated by 120 h. To study the lncRNA regulation in EEs, we proWled lncRNA expression by microarray and validated the results by qRT-PCR. Although the diVerential expression of several lncRNAs is suggestive of a role in epidermal diVerentiation, their biological functions remain to be elucidated. The current studies lay the foundation for relevant model systems to address such fundamentally important biological aspects of epidermal structure and function in normal and diseased human skin
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