Assessment of siltation and nutrient enrichment of Gilgel Gibe dam, Southwest Ethiopia

Gilgel Gibe hydroelectric power dam was located in the submerging part of the Addis Ababa, Jimma highway in Ethiopia which is about 55 km far from Jimma was constructed in 2004. A cross-sectional study was conducted during 2005 to assess the siltation and nutrient enrichment level of the dam. It was found from the study that siltation and nutrient enrichment were the major problems in this reservoir. The sheet erosion of catchment area was found to be 4.47x10(7) ton/year and hence 2210 ton/km(2). The contribution of the sediment load deposition of the Gilgel Gibe River to the dam was 277,437 ton/year and the total sediment load was 4.50x10(7)ton/year and this amount could cover 3.75x10(7) m(3)/year of the dam. From the analysis of water samples of Gilgel Gibe dam, the concentrations of ammonia, chlorophyll a, total dissolved solids (TDS), dissolved oxygen (DO), biological oxygen demand (BOD), pH and temperature were found within the permissible limits as prescribed by WHO standards, but other parameters like phosphate, nitrate, sulphate, total solids (TS), total suspended solids (TSS) and visibility were much higher than the permissible limits. Due to the high concentration of suspended and sediment load, the secchi disc visibility of Gilgel Gibe dam was 0.72 m which indicated that it was well within the range of eutrophic lakes.     

Genome-wide linkage analysis of systolic blood pressure slope using the Genetic Analysis Workshop 13 data sets

Systolic blood pressure (SBP) is an age-dependent complex trait for which both environmental and genetic factors may play a role in explaining variability among individuals. We performed a genome-wide scan of the rate of change in SBP over time on the Framingham Heart Study data and one randomly selected replicate of the simulated data from the Genetic Analysis Workshop 13. We used a variance-component model to carry out linkage analysis and a Markov chain Monte Carlo-based multiple imputation approach to recover missing information. Furthermore, we adopted two selection strategies along with the multiple imputation to deal with subjects taking antihypertensive treatment. The simulated data were used to compare these two strategies, to explore the effectiveness of the multiple imputation in recovering varying degrees of missing information, and its impact on linkage analysis results. For the Framingham data, the marker with the highest LOD score for SBP slope was found on chromosome 7. Interestingly, we found that SBP slopes were not heritable in males but were for females; the marker with the highest LOD score was found on chromosome 18. Using the simulated data, we found that handling treated subjects using the multiple imputation improved the linkage results. We conclude that multiple imputation is a promising approach in recovering missing information in longitudinal genetic studies and hence in improving subsequent linkage analyses.     

Local antagonism and resource partitioning between two invasive pine plantation pests

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Filtering Genes for Cluster and Network Analysis

Background  

Prior to cluster analysis or genetic network analysis it is customary to filter, or remove genes considered to be irrelevant from the set of genes to be analyzed. Often genes whose variation across samples is less than an arbitrary threshold value are deleted. This can improve interpretability and reduce bias.     

The Inner Membrane Protein PilG Interacts with DNA and the Secretin PilQ in Transformation

Expression of type IV pili (Tfp), filamentous appendages emanating from the bacterial surface, is indispensable for efficient neisserial transformation. Tfp pass through the secretin pore consisting of the membrane protein PilQ. PilG is a polytopic membrane protein, conserved in Gram-positive and Gram-negative bacteria, that is required for the biogenesis of neisserial Tfp. PilG null mutants are devoid of pili and non-competent for transformation. Here, recombinant full-length, truncated and mutated variants of meningococcal PilG were overexpressed, purified and characterized. We report that meningococcal PilG directly binds DNA in vitro, detected by both an electromobility shift analysis and a solid phase overlay assay. PilG DNA binding activity was independent of the presence of the consensus DNA uptake sequence. PilG-mediated DNA binding affinity was mapped to the N-terminus and was inactivated by mutation of residues 43 to 45. Notably, reduced meningococcal transformation of DNA in vivo was observed when PilG residues 43 to 45 were substituted by alanine in situ, defining a biologically significant DNA binding domain. N-terminal PilG also interacted with the N-terminal region of PilQ, which previously was shown to bind DNA. Collectively, these data suggest that PilG and PilQ in concert bind DNA during Tfp-mediated transformation.     

Quality control genotyping for assessment of genetic identity and purity in diverse tropical maize inbred lines

Quality control (QC) genotyping is an important component in breeding, but to our knowledge there are not well established protocols for its implementation in practical breeding programs. The objectives of our study were to (a) ascertain genetic identity among 2–4 seed sources of the same inbred line, (b) evaluate the extent of genetic homogeneity within inbred lines, and (c) identify a subset of highly informative single-nucleotide polymorphism (SNP) markers for routine and low-cost QC genotyping and suggest guidelines for data interpretation. We used a total of 28 maize inbred lines to study genetic identity among different seed sources by genotyping them with 532 and 1,065 SNPs using the KASPar and GoldenGate platforms, respectively. An additional set of 544 inbred lines was used for studying genetic homogeneity. The proportion of alleles that differed between seed sources of the same inbred line varied from 0.1 to 42.3?%. Seed sources exhibiting high levels of genetic distance are mis-labeled, while those with lower levels of difference are contaminated or still segregating. Genetic homogeneity varied from 68.7 to 100?% with 71.3?% of the inbred lines considered to be homogenous. Based on the data sets obtained for a wide range of sample sizes and diverse genetic backgrounds, we recommended a subset of 50–100 SNPs for routine and low-cost QC genotyping, verified them in a different set of double haploid and inbred lines, and outlined a protocol that could be used to minimize errors in genetic analyses and breeding.     

Magnitude and correlates of intimate partner violence against women and its outcome in Southwest Ethiopia

Background

Intimate Partner Violence (IPV) is a major public health problem with serious consequences. This study was conducted to assess the magnitude of IPV in Southwest Ethiopia in predominantly rural community.

Methods

This community based cross-sectional study was conducted in May, 2009 in Southwest Ethiopia using the World Health Organization core questionnaire to measure violence against women. Trained data collectors interviewed 851 ever-married women. Stata version 10.1 software and SPSS version 12.0.1 for windows were used for data analysis.

Result

In this study the life time prevalence of sexual or physical partner violence, or both was 64.7% (95%CI: 61.4%–67.9%). The lifetime sexual violence [50.1% (95% CI: 46.7%–53.4%)] was considerably more prevalent than physical violence [41.1% (95%:37.8–44.5)]. A sizable proportion [41.5%(95%CI: 38.2%–44.8%)] of women reported physical or sexual violence, or both, in the past year. Men who were controlling were more likely to be violent against their partner.

Conclusion

Physical and sexual violence is common among ever-married women in Southwest Ethiopia. Interventions targeting controlling men might help in reducing IPV. Further prospective longitudinal studies among ever-married women are important to identify predictors and to study the dynamics of violence over time.