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121.

Background

Given the proven effectiveness of voluntary medical male circumcision (VMMC) in preventing the spread of HIV, Tanzania is scaling up VMMC as an HIV prevention strategy. This study will inform policymakers about the potential costs and benefits of scaling up VMMC services in Tanzania.

Methodology

The analysis first assessed the unit costs of delivering VMMC at the facility level in three regions—Iringa, Kagera, and Mbeya—via three currently used VMMC service delivery models (routine, campaign, and mobile/island outreach). Subsequently, using these unit cost data estimates, the study used the Decision Makers'' Program Planning Tool (DMPPT) to estimate the costs and impact of a scaled-up VMMC program.

Results

Increasing VMMC could substantially reduce HIV infection. Scaling up adult VMMC to reach 87.9% coverage by 2015 would avert nearly 23,000 new adult HIV infections through 2015 and an additional 167,500 from 2016 through 2025—at an additional cost of US$253.7 million through 2015 and US$302.3 million from 2016 through 2025. Average cost per HIV infection averted would be US$11,300 during 2010–2015 and US$3,200 during 2010–2025. Scaling up VMMC in Tanzania will yield significant net benefits (benefits of treatment costs averted minus the cost of performing circumcisions) in the long run—around US$4,200 in net benefits for each infection averted.

Conclusion

VMMC could have an immediate impact on HIV transmission, but the full impact on prevalence and deaths will only be apparent in the longer term because VMMC averts infections some years into the future among people who have been circumcised. Given the health and economic benefits of investing in VMMC, the scale-up of services should continue to be a central component of the national HIV prevention strategy in Tanzania.  相似文献   
122.
ABSTRACT

The present work investigates the relationships between nitrogen fixation, carbon metabolism and oxygen consumption by bacteroids of Mesorhizobium ciceri in root nodules of chick-pea plants. Its aim was to establish whether some of the compounds which accumulate under salt stress may be used as respiratory substrates by bacteroids to fuel their own metabolism and nitrogenase activity. Plants were grown in a growth chamber, and salt stress was induced by adding 50 mM NaCl to the nutrient solution at sowing. The data presented here show a rise in fermentative metabolism in nodules of chick-pea plants exposed to high salinity, and suggest that proline, lactate or ethanol, may play an important role as energy-yielding substrates for bacteroids in this plant species. The bacteroids could utilize glucose as a respiratory substrate both under control and saline conditions, while malate did not appear to be the preferred substrate in the presence of salt.  相似文献   
123.

Conservation programmes are always limited by available resources. Careful planning is therefore required to increase the efficiency of conservation and gap analysis can be used for this purpose. This method was used to assess the representativeness of current ex situ and in situ conservation actions of 234 priority crop wild relatives (CWR) in Indonesia. This analysis also included species distribution modelling, the creation of an ecogeographical land characterization map, and a complementarity analysis to identify priorities area for in situ conservation and for further collecting of ex situ conservation programmes. The results show that both current ex situ and in situ conservation actions are insufficient. Sixty-six percent of priority CWRs have no recorded ex situ collections. Eighty CWRs with ex situ collections are still under-represented in the national genebanks and 65 CWRs have no presence records within the existing protected area network although 60 are predicted to exist in several protected areas according to their potential distribution models. The complementarity analysis shows that a minimum of 61 complementary grid areas (complementary based on grid cells) are required to conserve all priority taxa and 40 complementary protected areas (complementary based on existing protected areas) are required to conserve those with known populations within the existing in situ protected area network. The top ten of complementary protected areas are proposed as the initial areas for the development of CWR genetic reserves network in Indonesia. It is recommended to enhanced coordination between ex situ and in situ conservation stakeholders for sustaining the long term conservation of CWR in Indonesia. Implementation of the research recommendations will provide for the first time an effective conservation planning of Indonesia’s CWR diversity and will significantly enhance the country’s food and nutritional security.

  相似文献   
124.
Salt stress decreases plant growth prior to significant ion accumulation in the shoot. However, the processes underlying this rapid reduction in growth are still unknown. To understand the changes in salt stress responses through time and at multiple physiological levels, examining different plant processes within a single set-up is required. Recent advances in phenotyping has allowed the image-based estimation of plant growth, morphology, colour and photosynthetic activity. In this study, we examined the salt stress-induced responses of 191 Arabidopsis accessions from 1 h to 7 days after treatment using high-throughput phenotyping. Multivariate analyses and machine learning algorithms identified that quantum yield measured in the light-adapted state (Fv′/Fm′) greatly affected growth maintenance in the early phase of salt stress, whereas the maximum quantum yield (QYmax) was crucial at a later stage. In addition, our genome-wide association study (GWAS) identified 770 loci that were specific to salt stress, in which two loci associated with QYmax and Fv′/Fm′ were selected for validation using T-DNA insertion lines. We characterized an unknown protein kinase found in the QYmax locus that reduced photosynthetic efficiency and growth maintenance under salt stress. Understanding the molecular context of the candidate genes identified will provide valuable insights into the early plant responses to salt stress. Furthermore, our work incorporates high-throughput phenotyping, multivariate analyses and GWAS, uncovering details of temporal stress responses and identifying associations across different traits and time points, which are likely to constitute the genetic components of salinity tolerance.  相似文献   
125.
Multiple studies demonstrate the influence of the limbic system on the processing of sensory events and attentional guidance. But the mechanisms involved therein are yet not entirely clear. The close connection of handling incoming sensory information and memory retrieval, like in the case of habituation towards insignificant stimuli, suggests a crucial impact of the hippocampus on the direction of attention. In this paper we thus present a neurofunctional forward model of a hippocampal comparator function based on the theory of theta-regulated attention. Subsequently we integrated this comparator model into a multiscale framework for the simulation of evoked responses. The results of our simulations were compared to experimental data on electroencephalographic (EEG) correlates of habituation towards familiar stimuli using time-scale analysis. In consequence we are able to present additional evidence for limbic influences on the direction of attention driven by stimulus novelty and a systems neuroscience framework for the statements given in the theta-regulated attention hypothesis.  相似文献   
126.

Background

To describe the characteristics, clinical presentations, management and complications of snakebites in the border region between Al-Ain, United Arab Emirates (UAE) and Buraimi, Sultanate of Oman.

Methodology/Principal Findings

We carried out a retrospective review of medical records to study snakebite cases over four-year duration at three tertiary hospitals. Overall, 64 snakebite cases were studied with median hospitalization of 2 (interquartile range [IQR] 1–4) days. The majority of cases were male (87.5%), and most (61%) of the incidents occurred during summer months. The bite sites were predominantly (95%) to the feet and hands. Main clinical features included pain, local swelling, and coagulopathy, blistering and skin peeling. Overall, there were no deaths, but few major complications occurred; extensive skin peeling (n = 5, 8%), multi-organ failure (n = 1, 1.5%), and compartment syndrome (n = 1, 1.5%). Polyvalent anti snake venom (ASV), analgesia, tetanus toxoid, intravenous fluids, and antibiotics such as ampicillin, cloxacillin, and cephalosporins were commonly instituted as part of treatment protocols in the three hospitals.

Conclusion

The overwhelming majority of bites occurred during summer months, and envenomations were more common in, relatively, young male farmers, but with no serious clinical complications. Prevention and treatment strategies should include increasing public awareness, developing management guidelines, and manufacturing specific ASV for a wide spectrum of the local venomous snakes.  相似文献   
127.

Objectives

To determine the main predictors of all-cause and cardiovascular (CV) mortality in a rural West Indian population in Plymouth, Tobago over 30 years.

Methods

Questionnaire survey for CV risk factors and alcohol consumption patterns administered at baseline in 1976 with 92.5% response rate. 831/832 patients were followed up until 2005 or death.

Results

Hypertension (>140/90 mm Hg) was prevalent in 48% of men and 44% of women, and 21% of men and 17% of women had diabetes. Evidence showed most predictors for all cause and cardiovascular mortality having the main effects at ages <60 years, (p-value for interaction<0.01) but no risk factors having sex-specific effects on mortality. The main predictors of all-cause mortality at age <60 years in the fully adjusted model were high sessional alcohol intake (hazard ratio (HR) 2.04, 95% CI 1.10-3.80), severe hypertension >160/95 mm Hg (HR 1.68, 95% CI 1.09-2.60), diabetes (HR 3.28, 95% CI 1.89-5.69), and BMI (HR 1.04, 95% CI 1.00-1.07). The main predictors of cardiovascular mortality were similar in the fully adjusted model: high sessional alcohol intake (HR 2.47 95% CI 1.10-5.57), severe hypertension (HR 2.78 95% CI 1.56-4.95), diabetes (HR 3.68 95% CI 1.77-7.67) and additionally LVH, (HR 5.54 95% CI 1.38-22.26), however BMI did not show independent effects. For men, high sessional alcohol intake explains 27% of all cause mortality, and 40% of cardiovascular mortality at age <60 yrs. In adults aged <60 years, the attributable risk fraction for IGT/Diabetes and all cause mortality and cardiovascular mortality is 28% in women vs. 11% in men, and 22% in women vs. 6% in men respectively.

Conclusions

In this Afro-Caribbean population we found that a major proportion of deaths are attributable to high sessional alcohol intake (in males), diabetes, and hypertension and these risk factors primarily operate in those below 60 years.  相似文献   
128.
Rudabánya is rare among Eurasian Miocene fossil primate localities in preserving both a hominid and pliopithecoid, and as such provides the unique opportunity to reconstruct the nature of sympatry and niche partitioning in these taxa. Rudapithecus and Anapithecus have similar locomotor and positional behavior and overlapping body mass ranges. While prior analyses of molar occlusal anatomy and microwear identify Rudapithecus as a soft-object frugivore, reconstructing the dietary behavior of Anapithecus has been more problematic. This taxon has been interpreted to be more folivorous by some, and more frugivorous by others. Here, we use high-resolution polynomial curve fitting (HR-PCF) to quantify and evaluate the mesiodistal and cervico-incisal curvatures of the incisor crowns of Rudapithecus and Anapithecus to identify diet-specific morphological variation in these taxa. Results are consistent with the interpretation that Anapithecus and Rudapithecus were primarily frugivorous and had diets that included similar resource types. However, Anapithecus may have consumed greater amounts of foliage, similar to extant mixed folivore–frugivores (i.e., Gorilla gorilla gorilla, Symphalangus syndactylus), while Rudapithecus generated elevated compressive loads in the incisor region consistent with a specialized role for the anterior dentition in food processing (i.e., removal of tough protective fruit pericarps). We interpret these findings in light of the paleoecology at Rudabánya and conclude that, if these taxa were indeed sympatric, Anapithecus may have used additional leaf consumption as a seasonal fallback resource to avoid direct competition with Rudapithecus. Conversely, Rudapithecus may have relied on less preferred and harder fruiting resources as a seasonal fallback resource during periods of fruit scarcity.  相似文献   
129.
Functional Magnetic Resonance Imaging (fMRI) in the midbrain at 7 Tesla suffers from unexpectedly low temporal signal to noise ratio (TSNR) compared to other brain regions. Various methodologies were used in this study to quantitatively identify causes of the noise and signal differences in midbrain fMRI data. The influence of physiological noise sources was examined using RETROICOR, phase regression analysis, and power spectral analyses of contributions in the respiratory and cardiac frequency ranges. The impact of between-shot phase shifts in 3-D multi-shot sequences was tested using a one-dimensional (1-D) phase navigator approach. Additionally, the effects of shared noise influences between regions that were temporally, but not functionally, correlated with the midbrain (adjacent white matter and anterior cerebellum) were investigated via analyses with regressors of ‘no interest’. These attempts to reduce noise did not improve the overall TSNR in the midbrain. In addition, the steady state signal and noise were measured in the midbrain and the visual cortex for resting state data. We observed comparable steady state signals from both the midbrain and the cortex. However, the noise was 2–3 times higher in the midbrain relative to the cortex, confirming that the low TSNR in the midbrain was not due to low signal but rather a result of large signal variance. These temporal variations did not behave as known physiological or other noise sources, and were not mitigated by conventional strategies. Upon further investigation, resting state functional connectivity analysis in the midbrain showed strong intrinsic fluctuations between homologous midbrain regions. These data suggest that the low TSNR in the midbrain may originate from larger signal fluctuations arising from functional connectivity compared to cortex, rather than simply reflecting physiological noise.  相似文献   
130.
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