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181.

Objective

To determine the extent to which the narrowing of child mortality across wealth gradients has been related to foreign aid to the health sector in low- and middle-income countries.

Methods

Mortality and wealth data on 989,901 under-5 children from 957,674 households in 49 aid recipient countries in Africa, Asia, South America, and the Caribbean between 1993 and 2012 were used in the analysis. Declines in under-5 mortality in the four poorest wealth quantiles were compared to the decline among the wealthiest at varying levels of health aid per capita using fixed effects multivariable regression models and controlling for maternal education, urbanization, and domestic spending on health among recipient countries.

Results

Each additional dollar in total health aid per capita was associated with 5.7 fewer deaths per 10,000 child-years among children in the poorest relative to the wealthiest households (p<0.001). This was also true when measured in percent declines (1.90% faster decline in under-5 mortality among the poorest compared with the wealthiest with each dollar in total health aid, p = 0.008). The association was stronger when using health aid specifically for malaria than total health aid, 12.60% faster decline among the poorest compared with the wealthiest with each dollar in malaria aid, p = 0.001.

Conclusions

Foreign aid to the health sector is preferentially related to reductions in under-5 mortality among the poorest compared with the wealthiest. Health aid addressing malaria, which imposes a disproportionate burden among the poor, may explain the observed effect.  相似文献   
182.
Genome-wide association studies (GWAS) are widely used to search for genetic loci that underlie human disease. Another goal is to predict disease risk for different individuals given their genetic sequence. Such predictions could either be used as a “black box” in order to promote changes in life-style and screening for early diagnosis, or as a model that can be studied to better understand the mechanism of the disease. Current methods for risk prediction typically rank single nucleotide polymorphisms (SNPs) by the p-value of their association with the disease, and use the top-associated SNPs as input to a classification algorithm. However, the predictive power of such methods is relatively poor. To improve the predictive power, we devised BootRank, which uses bootstrapping in order to obtain a robust prioritization of SNPs for use in predictive models. We show that BootRank improves the ability to predict disease risk of unseen individuals in the Wellcome Trust Case Control Consortium (WTCCC) data and results in a more robust set of SNPs and a larger number of enriched pathways being associated with the different diseases. Finally, we show that combining BootRank with seven different classification algorithms improves performance compared to previous studies that used the WTCCC data. Notably, diseases for which BootRank results in the largest improvements were recently shown to have more heritability than previously thought, likely due to contributions from variants with low minimum allele frequency (MAF), suggesting that BootRank can be beneficial in cases where SNPs affecting the disease are poorly tagged or have low MAF. Overall, our results show that improving disease risk prediction from genotypic information may be a tangible goal, with potential implications for personalized disease screening and treatment.  相似文献   
183.
A new study exploits the time-dependence of formaldehyde cross-linking in the commonly used chromatin immunoprecipitation (ChIP) assay to infer the on and off rates for site-specific chromatin interactions.  相似文献   
184.
Wild strawberry (Fragaria vesca) fruit contains several important phenylpropene aroma compounds such as eugenol, but cultivated varieties are mostly devoid of them. We have redirected the carbon flux in cultivated strawberry (Fragaria×ananassa) fruit from anthocyanin pigment biosynthesis to the production of acetates of hydroxycinnamyl alcohols, which serve as the precursors of the phenylpropenes, by downregulating the strawberry chalcone synthase (CHS) via RNAi-mediated gene silencing and, alternatively, by an antisense CHS construct. Simultaneous heterologous overexpression of a eugenol (EGS) and isoeugenol synthase (IGS) gene in the same cultivated strawberry fruits boosted the formation of eugenol, isoeugenol, and the related phenylpropenes chavicol and anol to concentrations orders of magnitude greater than their odor thresholds. The results show that Fragaria×ananassa still bears a phenylpropene biosynthetic pathway but the carbon flux is primarily directed to the formation of pigments. Thus, partial restoration of wild strawberry flavor in cultivated varieties is feasible by diverting the flavonoid pathway to phenylpropene synthesis through metabolic engineering.  相似文献   
185.
Yanovich, R, Merkel, D, Israeli, E, Evans, RK, Erlich, T, and Moran, DS. Anemia, iron deficiency, and stress fractures in female combatants during 16 months. J Strength Cond Res 25(12): 3412-3421, 2011-The purpose of this study is to evaluate the hematological profile of military recruits in different settings and training programs and to investigate the link between anemia and iron deficiency with stress fracture (SF) occurrence. We surveyed 3 groups of recruits for 16 months: 221 women (F) and 78 men (M) from 3 different platoons of a gender-integrated combat battalion and a control group (CF) of 121 female soldiers from a noncombat unit. Data were fully collected upon induction and at 4 and 16 months from 48F, 21M, and 31CF. Blood tests, anthropometry, physical aerobic fitness, and SF occurrence were evaluated. On induction day, 18.0 and 19.0% of F and CF were found to be anemic, and 61.4 and 50.9%, respectively, were found to have iron deficiency, whereas 7.7% of M were found to be anemic and 10.2% iron deficient. During the 4 months of army basic training (ABT), anemia and iron deficiency prevalence did not change significantly in any group. After 16-months, anemia prevalence decreased by 8% among F and CF and abated in M. Iron deficiency was prevalent in 50.0, 59.4, and 18.8% of F, CF, and M, respectively. Stress fractures were diagnosed in 14 F during ABT, and they had a significantly higher prevalence (p < 0.05) of anemia and iron deficiency anemia compared to F without SFs. The observed link between anemia and iron deficiency on recruitment day and SFs suggests the importance of screening female combat recruits for these deficiencies. To minimize the health impact of army service on female soldiers, preventative measures related to anemia and iron deficiency should be administered. Further research is needed for evaluating the influence of low iron in kosher meat as a possible explanation for the high prevalence of iron deficiency among young Israeli recruits.  相似文献   
186.
Proteopedia is a collaborative, 3D web-encyclopedia of protein, nucleic acid and other biomolecule structures. Created as a means for communicating biomolecule structures to a diverse scientific audience, Proteopedia (http://www.proteopedia.org) presents structural annotation in an intuitive, interactive format and allows members of the scientific community to easily contribute their own annotations. Here, we provide a status report on Proteopedia by describing advances in the web resource since its inception three and a half years ago, focusing on features of potential direct use to the scientific community. We discuss its progress as a collaborative 3D-encyclopedia of structures as well as its use as a complement to scientific publications and PowerPoint presentations. We also describe Proteopedia's use for 3D visualization in structure-related pedagogy.  相似文献   
187.
Scorpions exhibit some of the lowest recorded water loss rates compared with those of other terrestrial arthropods of similar body size. Evaporative water loss (EWL) includes cuticular transpiration and respiratory water loss (RWL) from gas exchange surfaces, that is, book lung lamellae. Estimated fractions of cuticular and respiratory losses currently available from the literature show considerable variation, at least partly as a result of differences in methodology. This study reports RWL rates and their relative importance in scorpions from two families (Buthidae and Scorpionidae), including both xeric and mesic species (or subspecies). Two of the included Buthidae were surface-dwelling species, and another inhabits empty burrows of other terrestrial arthropods. This experimental design enabled correlating RWL importance with scorpion phylogeny, habitat type, and/or homing behavior. Buthidae species exhibited significantly lower EWL rates compared with those of Scorpionidae, whereas effects of habitat type and homing behavior were not significant. Resting RWL rates were not significantly affected by scorpion phylogeny, but rates for the xeric species (totaling ~10% of EWL rates at 30°C) were significantly lower compared with those of mesic species. These lower RWL values were correlated with significantly lower H(2)O/CO(2) emission rates in xeric species. The experimental setup and ~24-h duration of each individual recording allowed estimating the effect of interspecific variation in activity on RWL proportions. The high respiratory losses in active hydrated Scorpio maurus fuscus, totaling 30% of EWL, suggest that behavioral discretion in this species is a more likely mechanism for body water conservation under stressful conditions when compared with the responses of other studied species.  相似文献   
188.
An attack with Bacillus anthracis ("anthrax") is a known threat to the United States. When weaponized, it can cause inhalation anthrax, the deadliest form of the disease. Due to the rapid course of inhalation anthrax, delays in initiation of antibiotics may decrease survival chances. Because a rapid response would require cooperation from the public, there is a need to understand the public's response to possible mass dispensing programs. To examine the public's response to a mass prophylaxis program, this study used a nationally representative poll of 1,092 adults, supplemented by a targeted focus on 3 metropolitan areas where anthrax attacks occurred in 2001: New York City (n=517), Washington, DC (n=509), and Trenton/Mercer County, NJ (n=507). The poll was built around a "worst-case scenario" in which cases of inhalation anthrax are discovered without an identified source and the entire population of a city or town is asked to receive antibiotic prophylaxis within a 48-hour period. Findings from this poll provide important signs of public willingness to comply with public health recommendations for obtaining antibiotics from a dispensing site, although they also indicate that public health officials may face several challenges to compliance, including misinformation about the contagiousness of inhalation anthrax; fears about personal safety in crowds; distrust of government agencies to provide sufficient, safe, and effective medicine; and hesitation about ingesting antibiotic pills after receiving them. In general, people living in areas where anthrax attacks occurred in 2001 had responses similar to those of the nation as a whole.  相似文献   
189.
190.
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