Haptoglobin and Sickle Cell Polymorphisms and Risk of Active Trachoma in Gambian Children

BACKGROUND: Susceptibility and resistance to trachoma, the leading infectious cause of blindness, have been associated with a range of host genetic factors. In vitro studies of the causative organism, Chlamydia trachomatis, demonstrate that iron availability regulates its growth, suggesting that host genes involved in regulating iron status and/or availability may modulate the risk of trachoma. The objective was to investigate whether haptoglobin (Hp) haplotypes constructed from the functional polymorphism (Hp1/Hp2) plus the functional promoter SNPs -61A-C (rs5471) and -101C-G (rs5470), or sickle cell trait (HbAS, rs334) were associated with risk of active trachoma when stratified by age and sex, in rural Gambian children. METHODOLOGY AND PRINCIPAL FINDINGS: In two cross sectional surveys of children aged 6-78 months (n = 836), the prevalence of the clinical signs of active trachoma was 21.4%. Within boys, haplotype E (-101G, -61A, Hp1), containing the variant allele of the -101C-G promoter SNP, was associated with a two-fold increased risk of active trachoma (OR = 2.0 [1.17-3.44]). Within girls, an opposite association was non-significant (OR = 0.58 [0.32-1.04]; P = 0.07) and the interaction by sex was statistically significant (P = 0.001). There was no association between trachoma and HbAS. CONCLUSIONS: These data indicate that genetic variation in Hp may affect susceptibility to active trachoma differentially by sex in The Gambia

Design rainfall in Qatar: sensitivity to climate change scenarios

Design rainfall is needed in the design of numerous engineering infrastructures such as urban drainage systems, bridges, railways, metro systems, highways and flood levees. Design rainfall is derived using regional frequency analysis approach based on observed rainfall data from a large number of stations within a homogeneous region. This paper provides an assessment of the possible impacts of climate change on design rainfalls in Qatar. The future climate conditions are established based on AR4 and A2 categories of emission scenarios (SRES) specified by the Intergovernmental Panel on Climate Change. Predicted 24-h annual maximum rainfall series for both the wet (NCAR-CCSM) and dry scenarios (CSIRO-MK3.5) for the Qatari grid points are extracted for three different periods, which are current (2000–2029), medium-term (2040–2069) and end-of-century climates (2080–2099). Using an L-moments-based index frequency approach, homogeneous regions are established and the best-fit distribution is then used to derive rainfall quantiles for average recurrence intervals (ARIs) of 2, 5, 10, 25, 50 and 100 years. The results show that there is no significant change in the design rainfalls in Qatar in the short term covering 2040–2069; however, a significant change is predicted at the end of century covering 2080–2099. Updated design rainfalls are estimated considering climate change scenarios for the period of 2080–2099 by averaging results from the wet and dry climate scenarios. The increase in 24-h annual maximum rainfall for the period 2080–2099 (compared with the current period 2000–2029) is found to be in the range of 68 and 76 % for 100-year ARI. For the typical design ARIs of 10–20 years, the increase in design rainfall is found to be in the range of 43 and 54 %. The method presented in this study can be applied to other arid regions, in particular to the Middle Eastern countries

Urban Climate Change Vulnerability, Responses, and Policies in Qatar: An Assessment

Urban climate change policies are critical for reducing carbon emissions and increasing societal resilience to future risks. This is especially true for the countries of the Gulf Cooperation Council (GCC) which are arid environments with largely urban and coastal settlements. Their vulnerability to climate change impacts is high and has increased in the past due to economic growth, increased populations, wasteful lifestyles, urban expansion, and ongoing construction. Recently, in some of these countries, urban sustainable transformation is underway driven by new national agendas and ambitious megaprojects. This chapter assesses the ongoing urban climate change initiatives and policies in Qatar. It first introduces the overall urban climate change vulnerability in the context of urbanization, megaprojects, and economic growth. Later, it outlines current policies and initiatives. Using qualitative research and key informants’ interviews, urban climate policies are assessed with regard to gaps and strong points. They are also discussed in light of the country’s priorities and the regional context. Qatar’s urban climate policies are sketchy and rather embedded in national development frameworks and strategies. At the same time, there is a commitment toward incorporating climate change and emission reductions into the ongoing sustainable urbanization endeavors