Risco de salinização das terras do baixo Acaraú (CE)

Em determinadas condições de relevo, do clima e de uso, com certa frequência pode acontecer acúmulo de sais nos solos, dando lugar à formação dos solos salinos e sódicos - também denominados de solos afetados por sais. A fim de orientar as práticas de manejo e uso das terras da região do Baixo Acaraú, CE, objetivou-se com o presente trabalho gerar um mapa de risco de salinização. Para obtenção das classes de vulnerabilidade, foram avaliados os temas pedologia, geologia, geomorfologia e uso e cobertura das terras e informações de declividade e altimetria, tratados em ambiente SIG com o método multicritério aditivo. Foram definidas quatro classes de risco de salinização: baixo, moderado, alto e altíssimo ou solos naturalmente salinos/sódicos. Foi constatado que 35,47 % da área corresponde à classe de baixo risco de salinização; 26,22 %, à de risco moderado; 8,23 %, à de risco alto; e 19,65 %, à de risco altíssimo.

Risk of a Down syndrome live birth in women 45 years of age and older.

OBJECTIVES: To determine the risk of a Down syndrome (DS) live birth for women 45 years of age and over. METHODS: A meta-analysis of data from five published articles, 13 EUROCAT congenital anomaly population registers and two unpublished sources. RESULTS: Information was available on the number of DS live births occurring amongst 13,745 live births to women 45 years of age and over. Information was also available on DS pregnancies diagnosed prenatally that were subsequently terminated. These pregnancies were adjusted for expected fetal loss to estimate the number of live births that would have occurred in the absence of prenatal diagnoses, when a total of 471 DS live births were estimated to have occurred. The risk of a DS birth did not increase for women 45 years of age and over. The average risk was 34 per 1000 births (95% CI: 31-37). CONCLUSION: The risk of a DS live birth for women 45 years of age and over is considerably lower than has often been previously assumed. The most likely explanation is that women of this age are more likely to miscarry DS pregnancies than younger mothers.

Hundreds of variants clustered in genomic loci and biological pathways affect human height.

Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P < 0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways.

Association of genetic variation with systolic and diastolic blood pressure among African Americans: the Candidate Gene Association Resource study.

The prevalence of hypertension in African Americans (AAs) is higher than in other US groups; yet, few have performed genome-wide association studies (GWASs) in AA. Among people of European descent, GWASs have identified genetic variants at 13 loci that are associated with blood pressure. It is unknown if these variants confer susceptibility in people of African ancestry. Here, we examined genome-wide and candidate gene associations with systolic blood pressure (SBP) and diastolic blood pressure (DBP) using the Candidate Gene Association Resource (CARe) consortium consisting of 8591 AAs. Genotypes included genome-wide single-nucleotide polymorphism (SNP) data utilizing the Affymetrix 6.0 array with imputation to 2.5 million HapMap SNPs and candidate gene SNP data utilizing a 50K cardiovascular gene-centric array (ITMAT-Broad-CARe [IBC] array). For Affymetrix data, the strongest signal for DBP was rs10474346 (P= 3.6 × 10(-8)) located near GPR98 and ARRDC3. For SBP, the strongest signal was rs2258119 in C21orf91 (P= 4.7 × 10(-8)). The top IBC association for SBP was rs2012318 (P= 6.4 × 10(-6)) near SLC25A42 and for DBP was rs2523586 (P= 1.3 × 10(-6)) near HLA-B. None of the top variants replicated in additional AA (n = 11 882) or European-American (n = 69 899) cohorts. We replicated previously reported European-American blood pressure SNPs in our AA samples (SH2B3, P= 0.009; TBX3-TBX5, P= 0.03; and CSK-ULK3, P= 0.0004). These genetic loci represent the best evidence of genetic influences on SBP and DBP in AAs to date. More broadly, this work supports that notion that blood pressure among AAs is a trait with genetic underpinnings but also with significant complexity.

Adolescents i fotoblogs: la construcció de la identitat per mitjà del joc

Internet ha significat un nou paradigma en les relacions interpersonals, especialment entre els més joves. En aquest article analitzem la interacció de dos agents en el fenomen de la comunicació, els adolescents i els fotoblogs, amb una perspectiva teoricoespeculativa. El fotoblog és una eina virtual que els joves de tretze a setze anys, aproximadament, han adaptat a les seves necessitats per expressar les seves idees, sentiments o fantasies. Creiem que, en aquest entorn, els subjectes es poden comunicar en un espai on exploren el seu jo interior a partir de les representacions, signes i símbols que es mostren a la interfície. Actualment, l¿adolescent viu en un context eminentment visual i, així, doncs, no és gens estrany que les seves accions i formes comunicatives se centrin en «el que és visual», on el que és lineal i previsible deixa pas a la rapidesa, la retroalimentació i la continuïtat. Les formalitzacions que es mostren en la interfície són codis propis que els joves han creat per mostrar caracte- rístiques identitàries per mitjà de la imatge. Per tant, mantenim que per a l¿adolescent el fotoblog no solament és un mitjà, sinó també un ambient en el qual pot crear signes d¿identitat mitjançant les converses virtuals que estableix amb els seus iguals en un entorn lúdic i desinhibit, on juga amb la imatge en un procés de socialització.

Adolescentes y fotoblogs: la construcción de la identidad mediante el juego

Internet ha supuesto un nuevo paradigma en las relaciones interpersonales, especialmente entre los más jóvenes. En este artículo analizamos la interacción de dos agentes en el fenómeno de la comunicación, los adolescentes y los fotoblogs, con una perspectiva teórico-especulativa. El fotoblog es una herramienta virtual que los jóvenes de trece a dieciséis años, aproximadamente, han adaptado a sus necesidades para expresar sus ideas, sentimientos o fantasías. Creemos que, en este entorno, los sujetos pueden comunicarse en un espacio donde exploran su yo interior a partir de las representaciones, signos y símbolos que se muestran en la interfaz. En la actualidad, el adolescente vive en un contexto eminentemente visual y, así pues, no es de extrañar que sus acciones y formas comunicativas se centren en «lo visual», donde lo lineal y previsible deja paso a la rapidez, la retroalimentación y la continuidad. Las formalizaciones que se muestran en la interfaz son códigos propios que los jóvenes han creado para mostrar características identitarias mediante la imagen. Por tanto, mantenemos que para el adolescente el fotoblog no sólo es un medio, sino también un ambiente en el que puede crear signos de identidad por medio de las conversaciones virtuales que establece con sus pares en un entorno lúdico y desinhibido, donde juega con la imagen en un proceso de socialización.

Comunicació, imatge i aprenentatge

El objetivo de este trabajo es caracterizar algunos de los contextos comunicativos visuales a través de los cuales se producen, en la sociedad actual, aprendizajes no reglados. Aprender se da siempre en el sí de algún contexto comunicativo. Por lo tanto, las características fundamentales de la comunicación también lo son de los procesos de aprendizaje, incluso aquellos donde la imagen tiene un papel central. En este artículo se ofrece una caracterización general de la comunicación, atendiendo a sus vertientes más relevantes: socialización y transmisión de la información a través de signos (en especial, los visuales).

Decreased behavioral impairments in an Alzheimer mice model by interfering with TNF-alpha metabolism.

The performance of mice expressing PDAPP (+/+ or +/-) was studied in the Morris place navigation task. Different lines of questions were investigated using PDAPP+/- mice in which the activity of the cytokine Tumor Necrosing Factor alpha (TNFalpha) was attenuated by chronic treatment with anti-TNF or deleting TNFalpha (TNF-/-). Two different categories of behavior were analyzed in adult (6 months) and middle aged (15 months) subjects. Classically, the cognitive performance was assessed from the escape efficacy and quantitative bias toward the training position in a Morris water maze. Second, stereotyped circling was quantified, along with more qualitative behavioral impairments such as self-mutilation or increased reactivity. Our results can be summarized as follows. (1) All of the PDAPP mice expressed reduced cognitive performance in the Morris task, but only those with a clear-cut amyloid burden in the hippocampus showed behavioral abnormalities such as stereotyped circling. (2) Chronic treatment with anti-TNF prevented the development of pathological circling in the 6-month-old mice but not in the 15-month-old mice and had no significant effect on amyloid burden. (3) The absence of TNFalpha prevented the development of stereotyped circling in 6- and 15-month-old mice but increased amyloid burden after 15 months. These data indicate that PDAPP mice express cognitive impairments disregarding absence of TNF. The pathological behavioral anomalies related to the PDAPP mutation seem reduced by treatments interfering with TNFalpha.

O IBBD e a informação científica: uma perspectiva histórica para a ciência da informação no Brasil

Tradicionalmente se considera que a ciência da informação surgiu no Brasil em 1970, rompendo com um passado de práticas que não respondiam mais, de modo satisfatório, às demandas bibliográficas de uma comunidade científica em expansão. Após examinar a documentação reunida no arquivo pessoal de Lydia de Queiroz Sambaquy, bibliotecária que idealizou o Instituto Brasileiro de Bibliografia e Documentação (IBBD) e o presidiu entre 1954 e 1965, os resultados desta pesquisa histórica sugerem, ao contrário, que as atividades desenvolvidas no IBBD durante aqueles 11 anos caracterizavam já uma abordagem eminentemente "informacional" do trabalho bibliográfico, de acordo com as concepções de Farradane, um dos fundadores da área. Influenciados ao mesmo tempo pela biblioteconomia, pela documentação e pelo então moderníssimo conceito de "informação científica", os serviços prestados pelos bibliotecários do IBBD sob a liderança de Lydia Sambaquy abriram um novo campo de ação profissional, definindo as condições de possibilidade para a futura emergência da ciência da informação.

Large-scale association analyses identify new loci influencing glycemic traits and provide insight into the underlying biological pathways.

Through genome-wide association meta-analyses of up to 133,010 individuals of European ancestry without diabetes, including individuals newly genotyped using the Metabochip, we have increased the number of confirmed loci influencing glycemic traits to 53, of which 33 also increase type 2 diabetes risk (q < 0.05). Loci influencing fasting insulin concentration showed association with lipid levels and fat distribution, suggesting impact on insulin resistance. Gene-based analyses identified further biologically plausible loci, suggesting that additional loci beyond those reaching genome-wide significance are likely to represent real associations. This conclusion is supported by an excess of directionally consistent and nominally significant signals between discovery and follow-up studies. Functional analysis of these newly discovered loci will further improve our understanding of glycemic control.

BRF1 mutations alter RNA polymerase III-dependent transcription and cause neurodevelopmental anomalies.

RNA polymerase III (Pol III) synthesizes tRNAs and other small noncoding RNAs to regulate protein synthesis. Dysregulation of Pol III transcription has been linked to cancer, and germline mutations in genes encoding Pol III subunits or tRNA processing factors cause neurogenetic disorders in humans, such as hypomyelinating leukodystrophies and pontocerebellar hypoplasia. Here we describe an autosomal recessive disorder characterized by cerebellar hypoplasia and intellectual disability, as well as facial dysmorphic features, short stature, microcephaly, and dental anomalies. Whole-exome sequencing revealed biallelic missense alterations of BRF1 in three families. In support of the pathogenic potential of the discovered alleles, suppression or CRISPR-mediated deletion of brf1 in zebrafish embryos recapitulated key neurodevelopmental phenotypes; in vivo complementation showed all four candidate mutations to be pathogenic in an apparent isoform-specific context. BRF1 associates with BDP1 and TBP to form the transcription factor IIIB (TFIIIB), which recruits Pol III to target genes. We show that disease-causing mutations reduce Brf1 occupancy at tRNA target genes in Saccharomyces cerevisiae and impair cell growth. Moreover, BRF1 mutations reduce Pol III-related transcription activity in vitro. Taken together, our data show that BRF1 mutations that reduce protein activity cause neurodevelopmental anomalies, suggesting that BRF1-mediated Pol III transcription is required for normal cerebellar and cognitive development.

Genome-wide association scan meta-analysis identifies three Loci influencing adiposity and fat distribution.

To identify genetic loci influencing central obesity and fat distribution, we performed a meta-analysis of 16 genome-wide association studies (GWAS, N = 38,580) informative for adult waist circumference (WC) and waist-hip ratio (WHR). We selected 26 SNPs for follow-up, for which the evidence of association with measures of central adiposity (WC and/or WHR) was strong and disproportionate to that for overall adiposity or height. Follow-up studies in a maximum of 70,689 individuals identified two loci strongly associated with measures of central adiposity; these map near TFAP2B (WC, P = 1.9x10(-11)) and MSRA (WC, P = 8.9x10(-9)). A third locus, near LYPLAL1, was associated with WHR in women only (P = 2.6x10(-8)). The variants near TFAP2B appear to influence central adiposity through an effect on overall obesity/fat-mass, whereas LYPLAL1 displays a strong female-only association with fat distribution. By focusing on anthropometric measures of central obesity and fat distribution, we have identified three loci implicated in the regulation of human adiposity.