649 research outputs found

    HEER: Hybrid Energy Efficient Reactive Protocol for Wireless Sensor Networks

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    Wireless Sensor Networks (WSNs) consist of numerous sensors which send sensed data to base station. Energy conservation is an important issue for sensor nodes as they have limited power.Many routing protocols have been proposed earlier for energy efficiency of both homogeneous and heterogeneous environments. We can prolong our stability and network lifetime by reducing our energy consumption. In this research paper, we propose a protocol designed for the characteristics of a reactive homogeneous WSNs, HEER (Hybrid Energy Efficient Reactive) protocol. In HEER, Cluster Head(CH) selection is based on the ratio of residual energy of node and average energy of network. Moreover, to conserve more energy, we introduce Hard Threshold (HT) and Soft Threshold (ST). Finally, simulations show that our protocol has not only prolonged the network lifetime but also significantly increased stability period.Comment: 2nd IEEE Saudi International Electronics, Communications and Photonics Conference (SIECPC 13), 2013, Riyadh, Saudi Arabi

    Evidence for a Founder Effect among HIV-infected injection drug users (IDUs) in Pakistan.

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    Background: We have previously reported a HIV-1 subtype A infection in a community of injection drug users (IDUs) in Karachi, Pakistan. We now show that this infection among the IDUs may have originated from a single source. Methods: Phylogenetic analysis was performed of partial gag sequences, generated using PCR, from 26 HIV-positive IDU samples. Results: Our results showed formation of a tight monophyletic group with an intra-sequence identity of \u3c 98% indicating a founder effect . Our data indicate that the HIV-1 epidemic in this community of IDUs may have been transmitted by an HIV positive overseas contract worker who admitted to having contact with commercial sex workers during stay abroad. Conclusion: Specific measures need to implemented to control transmission of HIV infection in Pakistan through infected migrant workers

    True prevalence of twin HDV-HBV infection in Pakistan: a molecular approach

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    Hepatitis Delta Virus (HDV) infects only patients that are already infected by hepatitis B virus (HBV) because this is sub satellite virus which depends on and propagate only in the presence of HBV. HDV causes co-infection or super infection with sever complication as compared to only HBV infection. No study on molecular level on HDV is available from this region; therefore, the aim of this study was to found out the molecular epidemiology of HDV (as a co-infection with HBV) in different geographical regions of Pakistan

    Drinking Water Salinity and Raised Blood Pressure: Evidence from a Cohort Study in Coastal Bangladesh.

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    BACKGROUND: Millions of coastal inhabitants in Southeast Asia have been experiencing increasing sodium concentrations in their drinking-water sources, likely partially due to climate change. High (dietary) sodium intake has convincingly been proven to increase risk of hypertension; it remains unknown, however, whether consumption of sodium in drinking water could have similar effects on health. OBJECTIVES: We present the results of a cohort study in which we assessed the effects of drinking-water sodium (DWS) on blood pressure (BP) in coastal populations in Bangladesh. METHODS: DWS, BP, and information on personal, lifestyle, and environmental factors were collected from 581 participants. We used generalized linear latent and mixed methods to model the effects of DWS on BP and assessed the associations between changes in DWS and BP when participants experienced changing sodium levels in water, switched from "conventional" ponds or tube wells to alternatives [managed aquifer recharge (MAR) and rainwater harvesting] that aimed to reduce sodium levels, or experienced a combination of these changes. RESULTS: DWS concentrations were highly associated with BP after adjustments for confounding factors. Furthermore, for each 100 mg/L reduction in sodium in drinking water, systolic/diastolic BP was lower on average by 0.95/0.57 mmHg, and odds of hypertension were lower by 14%. However, MAR did not consistently lower sodium levels. CONCLUSIONS: DWS is an important source of daily sodium intake in salinity-affected areas and is a risk factor for hypertension. Considering the likely increasing trend in coastal salinity, prompt action is required. Because MAR showed variable effects, alternative technologies for providing reliable, safe, low-sodium fresh water should be developed alongside improvements in MAR and evaluated in "real-life" salinity-affected settings. https://doi.org/10.1289/EHP659

    Prevalence of HCV and HIV infections in 2005-Earthquake-affected areas of Pakistan

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    <p>Abstract</p> <p>Background</p> <p>On October 8, 2005, an earthquake of magnitude 7.6 hit the Northern parts of Pakistan. In the post-earthquake scenario, overcrowding, improper sewage disposal, contamination of food and drinking water, hasty surgical procedures, and unscreened blood transfusions to earthquake victims most likely promotes the spread of infections already prevalent in the area.</p> <p>Objective</p> <p>The objective of the study reported here was to determine the prevalence of Human Immunodeficiency and Hepatitis C viruses (respectively, HIV and HCV) in the earthquake-affected communities of Pakistan. The samples were analyzed 2 months and then again 11 months after the earthquake to estimate the burden of HIV and HCV in these areas, and to determine any rise in the prevalence of these viral infections as a result of the earthquake.</p> <p>Methods</p> <p>Blood samples were initially collected during December, 2005 to March 2006, from 245 inhabitants of the earthquake-affected areas. These samples were screened for HCV and HIV, using immunochromatography and Enzyme-Linked Immuno-Sorbent Assay (ELISA).</p> <p>Results</p> <p>Out of 245 samples tested, 8 (3.26%) were found positive for HCV, and 0 (0.0%) for HIV, indicating the existence of HCV infection in the earthquake-stricken areas. The same methods were used to analyze the samples collected in the second round of screening in the same area, in September, 2006 – 11 months after the earthquake. This time 290 blood samples were collected, out of which 16 (5.51%) samples were positive for HCV, and 0 for HIV.</p> <p>Conclusion</p> <p>A slightly higher prevalence of HCV was recorded 11 months after the earthquake; this increase, however, was not statistically significant. None of the study participants was found HIV-infected.</p

    Prevalence of anopheline species and their Plasmodium infection status in epidemic-prone border areas of Bangladesh

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    <p>Abstract</p> <p>Background</p> <p>Information related to malaria vectors is very limited in Bangladesh. In the changing environment and various <it>Anopheles </it>species may be incriminated and play role in the transmission cycle. This study was designed with an intention to identify anopheline species and possible malaria vectors in the border belt areas, where the malaria is endemic in Bangladesh.</p> <p>Methods</p> <p><it>Anopheles </it>mosquitoes were collected from three border belt areas (Lengura, Deorgachh and Matiranga) during the peak malaria transmission season (May to August). Three different methods were used: human landing catches, resting collecting by mouth aspirator and CDC light traps. Enzyme-linked immunosorbent assay (ELISA) was done to detect <it>Plasmodium falciparum</it>, <it>Plasmodium vivax</it>-210 and <it>Plasmodium vivax</it>-247 circumsporozoite proteins (CSP) from the collected female species.</p> <p>Results</p> <p>A total of 634 female <it>Anopheles </it>mosquitoes belonging to 17 species were collected. <it>Anopheles vagus </it>(was the dominant species (18.6%) followed by <it>Anopheles nigerrimus </it>(14.5%) and <it>Anopheles philippinensis </it>(11.0%). Infection rate was found 2.6% within 622 mosquitoes tested with CSP-ELISA. Eight (1.3%) mosquitoes belonging to five species were positive for <it>P. falciparum</it>, seven (1.1%) mosquitoes belonging to five species were positive for <it>P. vivax </it>-210 and a single mosquito (0.2%) identified as <it>Anopheles maculatus </it>was positive for <it>P. vivax</it>-247. No mixed infection was found. Highest infection rate was found in <it>Anopheles karwari </it>(22.2%) followed by <it>An. maculatus </it>(14.3%) and <it>Anopheles barbirostris </it>(9.5%). Other positive species were <it>An. nigerrimus </it>(4.4%), <it>An. vagus </it>(4.3%), <it>Anopheles subpictus </it>(1.5%) and <it>An. philippinensis </it>(1.4%). <it>Anopheles vagus </it>and <it>An. philippinensis </it>were previously incriminated as malaria vector in Bangladesh. In contrast, <it>An. karwari</it>, <it>An. maculatus</it>, <it>An. barbirostris</it>, <it>An. nigerrimus </it>and <it>An. subpictus </it>had never previously been incriminated in Bangladesh.</p> <p>Conclusion</p> <p>Findings of this study suggested that in absence of major malaria vectors there is a possibility that other <it>Anopheles </it>species may have been playing role in malaria transmission in Bangladesh. Therefore, further studies are required with the positive mosquito species found in this study to investigate their possible role in malaria transmission in Bangladesh.</p

    Real-time PCR assay and rapid diagnostic tests for the diagnosis of clinically suspected malaria patients in Bangladesh

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    <p>Abstract</p> <p>Background</p> <p>More than 95% of total malaria cases in Bangladesh are reported from the 13 high endemic districts. <it>Plasmodium falciparum </it>and <it>Plasmodium vivax </it>are the two most abundant malaria parasites in the country. To improve the detection and management of malaria patients, the National Malaria Control Programme (NMCP) has been using rapid diagnostic test (RDT) in the endemic areas. A study was conducted to establish a SYBR Green-based modified real-time PCR assay as a gold standard to evaluate the performance of four commercially-available malaria RDTs, along with the classical gold standard- microscopy.</p> <p>Methods</p> <p>Blood samples were collected from 338 febrile patients referred for the diagnosis of malaria by the attending physician at Matiranga</p> <p>Upazila Health Complex (UHC) from May 2009 to August 2010. Paracheck RDT and microscopy were performed at the UHC. The blood samples were preserved in EDTA tubes. A SYBR Green-based real-time PCR assay was performed and evaluated. The performances of the remaining three RDTs (Falcivax, Onsite Pf and Onsite Pf/Pv) were also evaluated against microscopy and real-time PCR using the stored blood samples.</p> <p>Result</p> <p>In total, 338 febrile patients were enrolled in the study. Malaria parasites were detected in 189 (55.9%) and 188 (55.6%) patients by microscopy and real-time PCR respectively. Among the RDTs, the highest sensitivity for the detection of <it>P. falciparum </it>(including mixed infection) was obtained by Paracheck [98.8%, 95% confidence interval (CI) 95.8-99.9] and Falcivax (97.6%, 95% CI 94.1-99.4) compared to microscopy and real-time PCR respectively. Paracheck and Onsite Pf/Pv gave the highest specificity (98.8%, 95% CI 95.7-99.9) compared to microscopy and Onsite Pf/Pv (98.8, 95% CI 95.8-99.9) compared to real-time PCR respectively for the detection of <it>P. falciparum</it>. On the other hand Falcivax and Onsite Pf/Pv had equal sensitivity (90.5%, 95% CI 69.6-98.8) and almost 100% specificity compared to microscopy for the detection of <it>P. vivax</it>. However, compared to real-time PCR assay RDTs and microscopy gave low sensitivity (76.9%, 95% CI 56.4-91) in detecting of <it>P. vivax </it>although a very high specificity was obtained (99- 100%).</p> <p>Conclusion</p> <p>The results of this study suggest that the SYBR Green-based real-time PCR assay could be used as an alternative gold standard method in a reference setting. Commercially-available RDTs used in the study are quite sensitive and specific in detecting <it>P. falciparum</it>, although their sensitivity in detecting <it>P. vivax </it>was not satisfactory compared to the real-time PCR assay.</p

    Mapping subnational HIV mortality in six Latin American countries with incomplete vital registration systems

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    Background: Human immunodeficiency virus (HIV) remains a public health priority in Latin America. While the burden of HIV is historically concentrated in urban areas and high-risk groups, subnational estimates that cover multiple countries and years are missing. This paucity is partially due to incomplete vital registration (VR) systems and statistical challenges related to estimating mortality rates in areas with low numbers of HIV deaths. In this analysis, we address this gap and provide novel estimates of the HIV mortality rate and the number of HIV deaths by age group, sex, and municipality in Brazil, Colombia, Costa Rica, Ecuador, Guatemala, and Mexico. Methods: We performed an ecological study using VR data ranging from 2000 to 2017, dependent on individual country data availability. We modeled HIV mortality using a Bayesian spatially explicit mixed-effects regression model that incorporates prior information on VR completeness. We calibrated our results to the Global Burden of Disease Study 2017. Results: All countries displayed over a 40-fold difference in HIV mortality between municipalities with the highest and lowest age-standardized HIV mortality rate in the last year of study for men, and over a 20-fold difference for women. Despite decreases in national HIV mortality in all countries—apart from Ecuador—across the period of study, we found broad variation in relative changes in HIV mortality at the municipality level and increasing relative inequality over time in all countries. In all six countries included in this analysis, 50% or more HIV deaths were concentrated in fewer than 10% of municipalities in the latest year of study. In addition, national age patterns reflected shifts in mortality to older age groups—the median age group among decedents ranged from 30 to 45 years of age at the municipality level in Brazil, Colombia, and Mexico in 2017. Conclusions: Our subnational estimates of HIV mortality revealed significant spatial variation and diverging local trends in HIV mortality over time and by age. This analysis provides a framework for incorporating data and uncertainty from incomplete VR systems and can help guide more geographically precise public health intervention to support HIV-related care and reduce HIV-related deaths

    Health in times of uncertainty in the eastern Mediterranean region, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013

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    Background: The eastern Mediterranean region is comprised of 22 countries: Afghanistan, Bahrain, Djibouti, Egypt, Iran, Iraq, Jordan, Kuwait, Lebanon, Libya, Morocco, Oman, Pakistan, Palestine, Qatar, Saudi Arabia, Somalia, Sudan, Syria, Tunisia, the United Arab Emirates, and Yemen. Since our Global Burden of Disease Study 2010 (GBD 2010), the region has faced unrest as a result of revolutions, wars, and the so-called Arab uprisings. The objective of this study was to present the burden of diseases, injuries, and risk factors in the eastern Mediterranean region as of 2013. Methods: GBD 2013 includes an annual assessment covering 188 countries from 1990 to 2013. The study covers 306 diseases and injuries, 1233 sequelae, and 79 risk factors. Our GBD 2013 analyses included the addition of new data through updated systematic reviews and through the contribution of unpublished data sources from collaborators, an updated version of modelling software, and several improvements in our methods. In this systematic analysis, we use data from GBD 2013 to analyse the burden of disease and injuries in the eastern Mediterranean region specifically. Findings: The leading cause of death in the region in 2013 was ischaemic heart disease (90·3 deaths per 100 000 people), which increased by 17·2% since 1990. However, diarrhoeal diseases were the leading cause of death in Somalia (186·7 deaths per 100 000 people) in 2013, which decreased by 26·9% since 1990. The leading cause of disability-adjusted life-years (DALYs) was ischaemic heart disease for males and lower respiratory infection for females. High blood pressure was the leading risk factor for DALYs in 2013, with an increase of 83·3% since 1990. Risk factors for DALYs varied by country. In low-income countries, childhood wasting was the leading cause of DALYs in Afghanistan, Somalia, and Yemen, whereas unsafe sex was the leading cause in Djibouti. Non-communicable risk factors were the leading cause of DALYs in high-income and middle-income countries in the region. DALY risk factors varied by age, with child and maternal malnutrition affecting the younger age groups (aged 28 days to 4 years), whereas high bodyweight and systolic blood pressure affected older people (aged 60–80 years). The proportion of DALYs attributed to high body-mass index increased from 3·7% to 7·5% between 1990 and 2013. Burden of mental health problems and drug use increased. Most increases in DALYs, especially from non-communicable diseases, were due to population growth. The crises in Egypt, Yemen, Libya, and Syria have resulted in a reduction in life expectancy; life expectancy in Syria would have been 5 years higher than that recorded for females and 6 years higher for males had the crisis not occurred. Interpretation: Our study shows that the eastern Mediterranean region is going through a crucial health phase. The Arab uprisings and the wars that followed, coupled with ageing and population growth, will have a major impact on the region's health and resources. The region has historically seen improvements in life expectancy and other health indicators, even under stress. However, the current situation will cause deteriorating health conditions for many countries and for many years and will have an impact on the region and the rest of the world. Based on our findings, we call for increased investment in health in the region in addition to reducing the conflicts
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