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A Test of a Strong Ground Motion Prediction Methodology for the 7 September 1999, Mw=6.0 Athens Earthquake
We test a methodology to predict the range of ground-motion hazard for a fixed magnitude earthquake along a specific fault or within a specific source volume, and we demonstrate how to incorporate this into probabilistic seismic hazard analyses (PSHA). We modeled ground motion with empirical Green's functions. We tested our methodology with the 7 September 1999, Mw=6.0 Athens earthquake, we: (1) developed constraints on rupture parameters based on prior knowledge of earthquake rupture processes and sources in the region; (2) generated impulsive point shear source empirical Green's functions by deconvolving out the source contribution of M < 4.0 aftershocks; (3) used aftershocks that occurred throughout the area and not necessarily along the fault to be modeled; (4) ran a sufficient number of scenario earthquakes to span the full variability of ground motion possible; (5) found that our distribution of synthesized ground motions span what actually occurred and their distribution is realistically narrow; (6) determined that one of our source models generates records that match observed time histories well; (7) found that certain combinations of rupture parameters produced ''extreme'' ground motions at some stations; (8) identified that the ''best fitting'' rupture models occurred in the vicinity of 38.05{sup o} N 23.60{sup o} W with center of rupture near 12 km, and near unilateral rupture towards the areas of high damage, and this is consistent with independent investigations; and (9) synthesized strong motion records in high damage areas for which records from the earthquake were not recorded. We then developed a demonstration PSHA for a source region near Athens utilizing synthesized ground motion rather that traditional attenuation. We synthesized 500 earthquakes distributed throughout the source zone likely to have Mw=6.0 earthquakes near Athens. We assumed an average return period of 1000 years for this magnitude earthquake in the particular source zone, thereby having simulated a catalog of ground motion for a period of 500,000 years. The distribution of traditional ground motion parameters of peak acceleration or spectral ordinates then becomes the synthesized record from which we develop hazard curves in the form of the annual probability of exceedance. This approach replaces the aleatory uncertainty that current PSHA studies estimate by regression of empirical parameters from the worldwide database with epistemic uncertainty on what specific sources actually do at specific sites. This is a fundamental change for PSHA and eliminates the need to extrapolate current empirical data that was gathered over about 50 years to represent values for 10{sup -3} annual probability of exceedance or less. This difference becomes especially significant for very sensitive structures that require estimates for 10{sup -5} or less exceedance
Correlação entre caracteres e análise de trilha em progênies de mamona (Ricinus communis L.) em condições de safrinha no estado de São Paulo.
Foi instalado um ensaio de avaliação de 73 progênies do Programa de Melhoramento de mamona do Instituto Agronômico que foi utilizado para estimar valores da correlação entre 12 caracteres agronômicos, em Campinas (SP), Brasil, em fevereiro, e avaliado na safrinha de 2007, em blocos casualizados com três repetições, incluindo sete testemunhas comerciais. A análise de trilha foi empregada para particionar os valores de correlação em efeitos diretos e indiretos sobre a produção de grãos. Valores de correlação positivos e significativos foram obtidos entre produção de grãos e todas as caracterÃsticas de arquitetura da planta, dos racemos primários e secundários e os componentes da produção avaliados. A altura da planta, altura, comprimento e número de frutos do racemo secundário, além da produção dos racemos primários e secundários tiveram efeitos diretos positivos sobre a produção de grãos, podendo ser utilizados na seleção indireta, nas condições de safrinha
An integrated modelling framework from cells to organism based on a cohort of digital embryos
We conducted a quantitative comparison of developing sea urchin embryos based on the analysis of five digital specimens obtained by automatic processing of in toto 3D+ time image data. These measurements served the reconstruction of a prototypical cell lineage tree able to predict the spatiotemporal cellular organisation of a normal sea urchin blastula. The reconstruction was achieved by designing and tuning a multi-level probabilistic model that reproduced embryo-level dynamics from a small number of statistical parameters characterising cell proliferation, cell surface area and cell volume evolution along the cell lineage. Our resulting artificial prototype was embedded in 3D space by biomechanical agent-based modelling and simulation, which allowed a systematic exploration and optimisation of free parameters to fit the experimental data and test biological hypotheses. The spherical monolayered blastula and the spatial arrangement of its different cell types appeared tightly constrained by cell stiffness, cell-adhesion parameters and blastocoel turgor pressure
Avaliação da arquitetura dos racemos e produção de progênies de mamona (Ricinus communis L.) em condições de safrinha no Estado de São Paulo.
Foi instalado um ensaio de avaliação com 73 progênies do Programa de Melhoramento de Mamona do Instituto Agronômico - IAC e sete materiais comerciais como testemunhas intercalares. O delineamento experimental foi em blocos casualisados com três repetições e as parcelas foram plantadas em fevereiro de 2007, em Campinas, SP. Foram avaliadas as caracterÃsticas dos racemos primários e secundários: quanto ao comprimento (CRP e CRS, em centÃmetros), número de frutos (NFRP e NFRS), produção de grãos (PRP e PRS, em gramas) e rendimento no descascamento (RRP e RRS, em %) de cinco plantas de 73 progênies de mamona desenvolvidas pelo Programa de Melhoramento. Foram conduzidas análises de variâncias sendo as progênies separadas pelo grupo de seleção sendo 42 da seleção PBII, 15 da seleção PB e 16 da seleção TS. Embora as condições ambientais não favoráveis da safrinha tenham contribuÃdo para o elevado coeficiente de variação observado para alguns caracteres, quadrados médios altamente significativos, para caracteres do racemo primário, foram encontrados para diferença entre médias de Genótipos, Genótipos dentro de PBII e entre Seleções, exceto para número de frutos que foi não significativo. Nos caracteres do racemo secundário, foram encontrados testes F altamente significativos (P<0,01) para diferenças entre Genótipos e entre Genótipos dentro do grupo PBII. Diferenças não significativas foram detectadas entre Seleções e entre Genótipos dentro do Grupo PB, exceto para rendimento no descascamento que apresentou P<0,05. São apresentadas as distribuições de médias para os caracteres
Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis
Background
Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy.
Methods
We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance.
Results
We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography.
Conclusion
Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data
A Digital Framework to Build, Visualize and Analyze a Gene Expression Atlas with Cellular Resolution in Zebrafish Early Embryogenesis
A gene expression atlas is an essential resource to quantify and understand the multiscale processes of embryogenesis in
time and space. The automated reconstruction of a prototypic 4D atlas for vertebrate early embryos, using multicolor
fluorescence in situ hybridization with nuclear counterstain, requires dedicated computational strategies. To this goal, we
designed an original methodological framework implemented in a software tool called Match-IT. With only minimal human
supervision, our system is able to gather gene expression patterns observed in different analyzed embryos with phenotypic
variability and map them onto a series of common 3D templates over time, creating a 4D atlas. This framework was used to
construct an atlas composed of 6 gene expression templates from a cohort of zebrafish early embryos spanning 6
developmental stages from 4 to 6.3 hpf (hours post fertilization). They included 53 specimens, 181,415 detected cell nuclei
and the segmentation of 98 gene expression patterns observed in 3D for 9 different genes. In addition, an interactive
visualization software, Atlas-IT, was developed to inspect, supervise and analyze the atlas. Match-IT and Atlas-IT, including
user manuals, representative datasets and video tutorials, are publicly and freely available online. We also propose
computational methods and tools for the quantitative assessment of the gene expression templates at the cellular scale,
with the identification, visualization and analysis of coexpression patterns, synexpression groups and their dynamics
through developmental stages
Effect of Multivitamin Supplementation on Measles Vaccine Response among HIV-exposed Uninfected Tanzanian Infants.
Immunization and nutritional interventions are mainstays of child health programs in sub-Saharan Africa, yet few published data exist on their interactions. HIV-exposed (but uninfected) infants enrolled in a randomized placebo-controlled trial of multivitamin supplements (vitamins B complex, C, and E) conducted in Tanzania were sampled for an assessment of measles IgG quantity and avidity at 15 to 18 months. Infants were vaccinated between 8.5 and 12 months of age, and all mothers received high-dose multivitamins as the standard of care. Of 201 HIV-exposed infants who were enrolled, 138 (68.7%) were seropositive for measles. There were no effects of infant multivitamin supplementation on measles seroconversion proportions, IgG concentrations, or IgG avidity (P > 0.05). The measles seroconversion proportion was greater for HIV-exposed infants vaccinated at 10 to 11 months of age than for those vaccinated at 8.5 to 10 months (P = 0.032) and greater for infants whose mothers had a CD4 T-cell count of <200 cells/μl than for infants whose mothers had a CD4 T-cell count of >350 cells/μl (P = 0.039). Stunted infants had a significantly decreased IgG quantity compared to nonstunted infants (P = 0.012). As for measles avidity, HIV-exposed infants vaccinated at 10 to 11 months had increased antibody avidity compared to those vaccinated at 8.5 to 10 months (P = 0.031). Maternal CD4 T-cell counts of <200 cells/μl were associated with decreased avidity compared to counts of >350 cells/μl (P = 0.047), as were lower infant height-for-age z-scores (P = 0.016). Supplementation with multivitamins containing B complex, C, and E does not appear to improve measles vaccine responses for HIV-exposed infants. Studies are needed to better characterize the impact of maternal HIV disease severity on the immune system development of HIV-exposed infants and the effect of malnutrition interventions on vaccine responses. (This study has been registered at ClinicalTrials.gov under registration no. NCT00197730.)
Does crop diversity contribute to dietary diversity? Evidence from integration of vegetables into maize-based farming systems
Background:
Maize is the most important staple crop for food security and livelihood of smallholder farmers in many parts of sub-Saharan Africa, but it alone cannot ensure food security. Cropping patterns must be diversified to ensure an adequate supply and economic access to greater variety of foods for smallholder farm households. This study measured the effect of crop diversification on household dietary diversity in a selected study locale using a survey of 300 randomly stratified farm households in 10 villages located in the Babati, Kongwa and Kiteto districts of Tanzania.
Results:
Based on multiple regression analysis, the study found that simply increasing Simpson’s Index does not influence dietary diversity of farm households due to the presence of interaction effect between Simpson’s Index and crop income. It is much more critical and significant to increase the revenue generated from diversified crops along with other socioeconomic endowment and behavioral characteristics of farm households. This is particularly applicable to poorer smallholder farmers who receive crop income less than US$85 per sales transaction and per season. Particularly, marginal and smallholders might be exposed to the effects of crop diversification and crop income toward increasing in their household dietary diversity score.
Conclusion:
Under average crop income scenarios, households that diversify their crop production tend to increase their dietary diversity from their existing dietary diversity score at a decreasing rate. However, under below average crop income threshold scenarios, farmers tend to increase their dietary diversity score from their existing score at an increasing rate when they diversify into high-value crops that attract relatively high farm gate values and accrue higher net revenues from the market. Monthly food expenditure also tends to positively influence household dietary diversity, indicating that farm households that spend more on market-purchased food have consistent increases in their dietary diversity scores at the household level. This study concludes that improving economic access to variety of foods at the smallholder household level by diversifying diets through increased crop diversification should be encouraged within maize-based farming systems of the study locale, through integration of micronutrient-rich foods such as vegetables
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