Photo-catalytic Removal of Methyl Orange Dye by Polyaniline Modified ZnO using Visible Radiation

Polyaniline modified zinc oxide (PANI/ZnO) nanocomposite was synthesized by in-situ polymerization process. The as-synthesized nano-ZnO, PANI and PANI/ZnO nanocomposite were characterized by X-ray diffraction (XRD), FT-IR, and UV-Vis spectroscopy. The UV–visible spectroscopy studies showed that the absorption peak for PANI/ZnO nanocomposite has a red shift toward visible wavelengths compared with the ZnO nanoparticles and PANI. Photocatalytic efficiency of PANI/ZnO nanocomposite was investigated for the degradation of methyl orange (MeO) dye as a model organic compound under Visible light irradiation. The photocatalytic activities of ZnO, PANI and PANI/ZnO nanocomposite were studied. The results showed that ZnO/PANI nanocomposite had greater photocatalytic activity than ZnO nanoparticles and PANI under visible light irradiation. According to these results, application of PANI as a shell on the surface of ZnO nanoparticles causes the enhanced photocatalytic activity of the PANI/ZnO nanocomposite. Influence of some operational parameters such as: amount of photocatalyst, pH of solution, and MeO dye initial concentration on the photodegradation reaction rate was investigated. The optimum values of pH and catalyst dose found to be 6 and 1.50 gmL-1 respectively. It was demonstrated that the photocatalytic degradation of MeO follows pseudo first-order kinetics. The PANI/ZnO nanocomposite photocatalysts have good photocatalytic stability and can be reused three times with only gradual loss of activity. Thus, the PANI/ZnO nanocomposites are efficient photocatalytic materials for degrading contaminated colored wastewater for reuse in textile industries under mild conditions.Keywords: PANI/ZnO Nanocomposite; Methyl orange; Visible light; photo-catalysis; Degradation rate constan

In vivo anti-malarial activity of hydroalcoholic extracts from Asparagus africanus Lam. in mice infected with Plasmodium berghei

Background: Malaria is a major public health problem in the world in general and developing countries in particular, causing an estimated 1-2 million deaths per year, an annual incidence of 300-500 million clinical cases and more than 2 billion people are at risk of infection from it. But it is also becoming more difficult to treat malaria due to the increasing drug resistance. Therefore, the need for alternative drugs is acute. Objective: The This study aims at investigating the in vivo antiplasmodial activity of extracts of the roots and area parts from traditionally used medicinal plant, named Asparagus africanus (Liliaceae). Methods: A rodent malaria parasite, Plasmodium berghei, which was maintained at the Ethiopian Health and Nutrition Research Institute (EHNRI) laboratory, was inoculated into Swiss albino mice. The mice were infected with 1x107 parasites intraperitoneally. The extracts were administered by an intra gastric tube daily for four days starting from the day of parasite inoculation. The control groups received the same amount of solvent (vehicle) used to suspend each dose of the herbal drug. Chloroquine was used as a standard drug, and was administered through the same route. Results: Extracts from the roots and aerial parts of A.africanus were observed to inhibit Plasmodium berghei parasitaemia in the Swiss albino mice by 46.1% and 40.7% respectively. Conclusion: The study could partly confirm the claim in Ethiopian traditional medicine that the plant has therapeutic values in human malaria. There is, thus, the need to initiate further in-depth investigation by using different experimental models. The Ethiopian Journal of Health Development Vol. 20 (2) 2006: 112-11

Mercury in the Black Sea:New Insights From Measurements and Numerical Modeling

Redox conditions and organic matter control marine methylmercury (MeHg) production. The Black Sea is the world's largest and deepest anoxic basin and is thus ideal to study Hg species along the extended redox gradient. Here we present new dissolved Hg and MeHg data from the 2013 GEOTRACES MEDBlack cruise (GN04_leg2) that we integrated into a numerical 1-D model, to track the fate and dynamics of Hg and MeHg. Contrary to a previous study, our new data show highest MeHg concentrations in the permanently anoxic waters. Observed MeHg/Hg percentage (range 9-57%) in the anoxic waters is comparable to other subsurface maxima in oxic open-ocean waters. With the modeling we tested for various Hg methylation and demethylation scenarios along the redox gradient. The results show that Hg methylation must occur in the anoxic waters. The model was then used to simulate the time evolution (1850-2050) of Hg species in the Black Sea. Our findings quantify (1) inputs and outputs of Hg-T (similar to 31 and similar to 28 kmol yr(-1)) and MeHgT (similar to 5 and similar to 4 kmol yr(-1)) to the basin, (2) the extent of net demethylation occurring in oxic (similar to 1 kmol yr(-1)) and suboxic water (similar to 6 kmol yr(-1)), (3) and the net Hg methylation in the anoxic waters of the Black Sea (similar to 11 kmol yr(-1)). The model was also used to estimate the amount of anthropogenic Hg (85-93%) in the Black Sea

HIV/AIDS-related mortality in Africa and Asia: evidence from INDEPTH health and demographic surveillance system sites

This paper is part of the Special Issue : INDEPTH Network Cause-Specific MortalityAs the HIV/AIDS pandemic has evolved over recent decades, Africa has been the most affected region, even though a large proportion of HIV/AIDS deaths have not been documented at the individual level. Systematic application of verbal autopsy (VA) methods in defined populations provides an opportunity to assess the mortality burden of the pandemic from individual data.To present standardised comparisons of HIV/AIDS-related mortality at sites across Africa and Asia, including closely related causes of death such as pulmonary tuberculosis (PTB) and pneumonia.Deaths related to HIV/AIDS were extracted from individual demographic and VA data from 22 INDEPTH sites across Africa and Asia. VA data were standardised to WHO 2012 standard causes of death assigned using the InterVA-4 model. Between-site comparisons of mortality rates were standardised using the INDEPTH 2013 standard population.The dataset covered a total of 10,773 deaths attributed to HIV/AIDS, observed over 12,204,043 person-years. HIV/AIDS-related mortality fractions and mortality rates varied widely across Africa and Asia, with highest burdens in eastern and southern Africa, and lowest burdens in Asia. There was evidence of rapidly declining rates at the sites with the heaviest burdens. HIV/AIDS mortality was also strongly related to PTB mortality. On a country basis, there were strong similarities between HIV/AIDS mortality rates at INDEPTH sites and those derived from modelled estimates.Measuring HIV/AIDS-related mortality continues to be a challenging issue, all the more so as anti-retroviral treatment programmes alleviate mortality risks. The congruence between these results and other estimates adds plausibility to both approaches. These data, covering some of the highest mortality observed during the pandemic, will be an important baseline for understanding the future decline of HIV/AIDS.P. Kim Streatfield ... Yohannes A. Melaku ... et.al

Adult non-communicable disease mortality in Africa and Asia: evidence from INDEPTH Health and Demographic Surveillance System sites

Background: Mortality from non-communicable diseases (NCDs) is a major global issue, as other categories of mortality have diminished and life expectancy has increased. The World Health Organization's Member States have called for a 25% reduction in premature NCD mortality by 2025, which can only be achieved by substantial reductions in risk factors and improvements in the management of chronic conditions. A high burden of NCD mortality among much older people, who have survived other hazards, is inevitable. The INDEPTH Network collects detailed individual data within defined Health and Demographic Surveillance sites. By registering deaths and carrying out verbal autopsies to determine cause of death across many such sites, using standardised methods, the Network seeks to generate population-based mortality statistics that are not otherwise available. Objective: To describe patterns of adult NCD mortality from INDEPTH Network sites across Africa and Asia, according to the WHO 2012 verbal autopsy (VA) cause categories, with separate consideration of premature (15–64 years) and older (65+ years) NCD mortality. Design: All adult deaths at INDEPTH sites are routinely registered and followed up with VA interviews. For this study, VA archives were transformed into the WHO 2012 VA standard format and processed using the InterVA-4 model to assign cause of death. Routine surveillance data also provide person-time denominators for mortality rates. Results: A total of 80,726 adult (over 15 years) deaths were documented over 7,423,497 person-years of observation. NCDs were attributed as the cause for 35.6% of these deaths. Slightly less than half of adult NCD deaths occurred in the 15–64 age group. Detailed results are presented by age and sex for leading causes of NCD mortality. Per-site rates of NCD mortality were significantly correlated with rates of HIV/AIDS-related mortality. Conclusions: These findings present important evidence on the distribution of NCD mortality across a wide range of African and Asian settings. This comes against a background of global concern about the burden of NCD mortality, especially among adults aged under 70, and provides an important baseline for future work.P. Kim Streatfield ... Yohannes A. Melaku ... et al

Mortality from external causes in Africa and Asia: evidence from INDEPTH health and demographic surveillance system sites

This paper is part of the Special Issue: INDEPTH Network Cause-Specific MortalityMortality from external causes, of all kinds, is an important component of overall mortality on a global basis. However, these deaths, like others in Africa and Asia, are often not counted or documented on an individual basis. Overviews of the state of external cause mortality in Africa and Asia are therefore based on uncertain information. The INDEPTH Network maintains longitudinal surveillance, including cause of death, at population sites across Africa and Asia, which offers important opportunities to document external cause mortality at the population level across a range of settings.To describe patterns of mortality from external causes at INDEPTH Network sites across Africa and Asia, according to the WHO 2012 verbal autopsy (VA) cause categories.All deaths at INDEPTH sites are routinely registered and followed up with VA interviews. For this study, VA archives were transformed into the WHO 2012 VA standard format and processed using the InterVA-4 model to assign cause of death. Routine surveillance data also provide person-time denominators for mortality rates.A total of 5,884 deaths due to external causes were documented over 11,828,253 person-years. Approximately one-quarter of those deaths were to children younger than 15 years. Causes of death were dominated by childhood drowning in Bangladesh, and by transport-related deaths and intentional injuries elsewhere. Detailed mortality rates are presented by cause of death, age group, and sex.The patterns of external cause mortality found here generally corresponded with expectations and other sources of information, but they fill some important gaps in population-based mortality data. They provide an important source of information to inform potentially preventive intervention designs.P. Kim Streatfield ... Yohannes A. Melaku ... et. al

Malaria mortality in Africa and Asia: evidence from INDEPTH health and demographic surveillance system sites

This paper is part of the Special Issue: INDEPTH Network Cause-Specific Mortality. A Corrigendum has been published for this paper. Please see http://www.globalhealthaction.net/index.php/ gha/article/view/27833Malaria continues to be a major cause of infectious disease mortality in tropical regions. However, deaths from malaria are most often not individually documented, and as a result overall understanding of malaria epidemiology is inadequate. INDEPTH Network members maintain population surveillance in Health and Demographic Surveillance System sites across Africa and Asia, in which individual deaths are followed up with verbal autopsies.To present patterns of malaria mortality determined by verbal autopsy from INDEPTH sites across Africa and Asia, comparing these findings with other relevant information on malaria in the same regions.From a database covering 111,910 deaths over 12,204,043 person-years in 22 sites, in which verbal autopsy data were handled according to the WHO 2012 standard and processed using the InterVA-4 model, over 6,000 deaths were attributed to malaria. The overall period covered was 1992-2012, but two-thirds of the observations related to 2006-2012. These deaths were analysed by site, time period, age group and sex to investigate epidemiological differences in malaria mortality.Rates of malaria mortality varied by 1:10,000 across the sites, with generally low rates in Asia (one site recording no malaria deaths over 0.5 million person-years) and some of the highest rates in West Africa (Nouna, Burkina Faso: 2.47 per 1,000 person-years). Childhood malaria mortality rates were strongly correlated with Malaria Atlas Project estimates of Plasmodium falciparum parasite rates for the same locations. Adult malaria mortality rates, while lower than corresponding childhood rates, were strongly correlated with childhood rates at the site level.The wide variations observed in malaria mortality, which were nevertheless consistent with various other estimates, suggest that population-based registration of deaths using verbal autopsy is a useful approach to understanding the details of malaria epidemiology.P. Kim Streatfield ... Yohannes A. Melaku ... et. al

Prediction of Low Community Sanitation Coverage Using Environmental and Sociodemographic Factors in Amhara Region, Ethiopia.

This study developed and validated a model for predicting the probability that communities in Amhara Region, Ethiopia, have low sanitation coverage, based on environmental and sociodemographic conditions. Community sanitation coverage was measured between 2011 and 2014 through trachoma control program evaluation surveys. Information on environmental and sociodemographic conditions was obtained from available data sources and linked with community data using a geographic information system. Logistic regression was used to identify predictors of low community sanitation coverage (< 20% versus ≥ 20%). The selected model was geographically and temporally validated. Model-predicted probabilities of low community sanitation coverage were mapped. Among 1,502 communities, 344 (22.90%) had coverage below 20%. The selected model included measures for high topsoil gravel content, an indicator for low-lying land, population density, altitude, and rainfall and had reasonable predictive discrimination (area under the curve = 0.75, 95% confidence interval = 0.72, 0.78). Measures of soil stability were strongly associated with low community sanitation coverage, controlling for community wealth, and other factors. A model using available environmental and sociodemographic data predicted low community sanitation coverage for areas across Amhara Region with fair discrimination. This approach could assist sanitation programs and trachoma control programs, scaling up or in hyperendemic areas, to target vulnerable areas with additional activities or alternate technologies

Global wild rice germplasm resources conservation alliance: World Wild-Rice Wiring

Comment Wild relatives of crop are key genetic resources serving as diversity reservoirs for crop improvement under changing environments. Rice (Oryza sativa) is one of the most important crops in the world, providing staple food for half of the world’s population. Wild rice is thus a critical germplasm resource for sustained global food security, ensuring high production yields, improved quality, and stress resistance in the face of climate change. Wild rice is closely related to domesticated rice and has a rich genetic diversity and exceptional adaptability to extreme environments. It has played a pivotal role in the history of rice hybridization and has become a key resource for rice breeding programs. The identification of wild-type cytoplasmic male sterility resources paved the way for the achievement of the ‘‘three lines’’ goal in hybrid rice, leading to a significant increase in rice yields. In addition, the use of resistance alleles found in wild rice is making rice production more resilient to losses caused by environmental stresses. However, wild rice germplasm resources are threatened due to habitat destruction and other anthropogenic factors. At the same time, the lack of centralized distribution of wild rice has hampered the sharing of basic information on wild rice resources and the utilization and conservation of wild rice in each country, as well as collaboration among scientists