Efficient GTS Allocation Schemes for IEEE 802.15.4

IEEE 802.15.4 is a standard defined for wireless sensor network applications with limited power and relaxed throughput needs. The devices transmit data during two periods: Contention Access Period (CAP) by accessing the channel using CSMA/CA and Contention Free Period (CFP), which consists of Guaranteed Time Slots (GTS) allocated to individual devices by the network coordinator. The GTS is used by devices for cyclic data transmission and the coordinator can allocate GTS to a maximum of only seven devices. In this work, we have proposed two algorithms for an efficient GTS allocation. The first algorithm is focused on improving the bandwidth utilization of devices, while the second algorithm uses traffic arrival information of devices to allow sharing of GTS slots between more than seven devices. The proposed schemes were tested through simulations and the results show that the new GTS allocation schemes perform better than the original IEEE 802.15.4 standard

Progress and challenges to control malaria in a remote area of Chittagong hill tracts, Bangladesh

<p>Abstract</p> <p>Background</p> <p>Malaria is endemic in 13 eastern districts where the overall infection prevalence is 3.97%. In 2006, Bangladesh received US$ 36.9 million from the Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM) to support the national malaria control programme of Bangladesh.</p> <p>Objectives</p> <p>The objective of this study was to i) clarify factors associated with treatment seeking behaviours of malaria ii) distribution of LLIN, and iii) re-treatment of ITN in remote area of a CHT district of Bangladesh two years after implementation of national control programme.</p> <p>Methods</p> <p>All households of Rajasthali sub-district of Rangamati district (households about 5,322, population about 24,097), all BRAC health workers (n = 15), health facilities and drug vendors' locations were mapped. Distances from households to health facilities, BRAC health workers and drug vendors were calculated. Logistic regression analysis was performed to assess the associations between the choice of the treatment and the distance to various treatment sources, education, occupation and ethnicity. SaTScan was used to detect clustering of treatment-seeking approaches.</p> <p>Findings</p> <p>LLIN distribution and the re-treatment of ITN exceeded target goals. The most common treatment facility for malaria-associated fever was malaria control programme led by BRAC and government (66.6%) followed by the drug vendor (48.8%).</p> <p>Conclusion</p> <p>Closeness to health facilities run by the malaria control programme and drug vendors were significantly associated with the choice of treatment. A high proportion of people preferred drug vendors without having a proper diagnosis. Drug vendors are highly patronized and thus there is a need to improve their services for public health good. Otherwise it may cause incomplete treatment, misuse of anti-malarial drugs that will contribute to the risk of drug resistance and jeopardize the present malaria control efforts in Bangladesh.</p

Wealth inequality and utilization of reproductive health services in the Republic of Vanuatu: insights from the multiple indicator cluster survey, 2007

<p>Abstract</p> <p>Background</p> <p>Although the Republic of Vanuatu has improved maternal indicators, more needs to be done to improve equity among the poorest in the use of reproductive health services to expedite the progress towards the Millennium Development Goal 5(MDG 5) target. While large developing country studies provide evidence of a rich-poor gap in reproductive health services utilization, not much is written in terms of Pacific Islands. Thus, this study aims to examine the degree of inequality in utilization of reproductive health services in a nationally representative sample of Vanuatu households.</p> <p>Methods</p> <p>This paper used data from the 2007 Vanuatu Multiple Indicator Cluster Survey (MICS). The analyses were based on responses from 615 ever married women, living with at least one child below two years of age. Outcomes included antenatal care (ANC) and use of birth attendants at delivery, place of delivery, and counseling and testing for HIV/AIDS. Descriptive statistics and multivariate logistic regression methods were employed in the analysis.</p> <p>Results</p> <p>Findings revealed that the economic well-being status of the household to which women belong, played a crucial role in explaining the variation in service utilization. Inequality in utilization was found to be more pronounced between the poorest and richest groups within the wealth quintiles. In adjusted models, mothers in the richest bands of wealth were 5.50 (95% confidence interval [CI]: 1.34-22.47), 2.12 (95% CI: 1.02-3.42), 4.0 (95% CI 1.58-10.10), and 2.0 (95% CI 1.02-5.88) times more likely to have assisted delivery from medically trained personnel, have institutional deliveries, and have counseling and testing for HIV/AIDS.</p> <p>Conclusions</p> <p>Association between household wealth inequality and utilization of ANC and delivery assistance from medically trained personnel, institutional delivery, and counseling and testing for HIV/AIDS suggest that higher utilization of reproductive health care services in Vanuatu poor-rich inequalities need to be addressed. Reducing poverty and making services more available and accessible to the poor may be essential for improving overall reproductive health care utilization rate in Vanuatu.</p

Risk factors associated with clinical malaria episodes in Bangladesh: A longitudinal study

Malaria is endemic to Bangladesh. In this longitudinal study, we used hydrologic, topographic, and socioeconomic risk factors to explain single and multiple malaria infections at individual and household levels. Malaria incidence was determined for 1,634 households in 54 villages in 2009 and 2010. During the entire study period 21.8% of households accounted for all (n = 497) malaria cases detected; 15.4% of households had 1 case and 6.4% had ≥2 cases. The greatest risk factors for malaria infection were low bed net ratio per household, house construction materials (wall), and high density of houses. Hydrologic and topographic factors were not significantly associated with malaria risk. This study identifies stable malaria hotspots and risk factors that should be considered for cost-effective targeting of malaria interventions that may contribute to potential elimination of malaria in Bangladesh. Copyright © 2013 by The American Society of Tropical Medicine and Hygiene

Spatial prediction of malaria prevalence in an endemic area of Bangladesh

<p>Abstract</p> <p>Background</p> <p>Malaria is a major public health burden in Southeastern Bangladesh, particularly in the Chittagong Hill Tracts region. Malaria is endemic in 13 districts of Bangladesh and the highest prevalence occurs in Khagrachari (15.47%).</p> <p>Methods</p> <p>A risk map was developed and geographic risk factors identified using a Bayesian approach. The Bayesian geostatistical model was developed from previously identified individual and environmental covariates (p < 0.2; age, different forest types, elevation and economic status) for malaria prevalence using WinBUGS 1.4. Spatial correlation was estimated within a Bayesian framework based on a geostatistical model. The infection status (positives and negatives) was modeled using a Bernoulli distribution. Maps of the posterior distributions of predicted prevalence were developed in geographic information system (GIS).</p> <p>Results</p> <p>Predicted high prevalence areas were located along the north-eastern areas, and central part of the study area. Low to moderate prevalence areas were predicted in the southwestern, southeastern and central regions. Individual age and nearness to fragmented forest were associated with malaria prevalence after adjusting the spatial auto-correlation.</p> <p>Conclusion</p> <p>A Bayesian analytical approach using multiple enabling technologies (geographic information systems, global positioning systems, and remote sensing) provide a strategy to characterize spatial heterogeneity in malaria risk at a fine scale. Even in the most hyper endemic region of Bangladesh there is substantial spatial heterogeneity in risk. Areas that are predicted to be at high risk, based on the environment but that have not been reached by surveys are identified.</p

Content Analysis of Primary and Secondary School Textbooks Regarding Malaria Control: A Multi-Country Study

BACKGROUND: In tropical settings, malaria education at school is potentially useful, but textbook content related to malaria education has so far received little attention. This study aimed to examine whether school textbooks contain sufficient knowledge and skills to help children in primary and lower secondary schools and their family members to cope with malaria. METHODOLOGY/PRINCIPAL FINDINGS: This was a descriptive, cross-country study. We collected textbooks that were used by children in grades one to nine from nine countries endemic for malaria: Laos, Cambodia, Nepal, Bangladesh, Sri Lanka, Zambia, Niger, Benin, and Ghana. Two reviewers per country identified descriptions about malaria by seeking the term "malaria" or a local word that corresponds to malaria in languages other than English. The authors categorized the identified descriptions according to the content of the descriptions. Additionally, the authors examined whether the identified contents addressed life skill messages. Of a total of 474 textbooks collected, 35 contained descriptions about malaria. The most commonly included content was transmission mode/vector (77.1%), followed by preventive measures (60.0%), epidemiology (57.1%), cause/agent (54.3%), signs/symptoms (37.1%) and treatment (22.9%). Treatment-related content was not included in any textbooks from four countries and textbooks failed to recommend the use of insecticide-treated bed nets in five countries. Very few textbooks included content that facilitated prompt treatment, protection of risk groups, and use of recommended therapy. CONCLUSION/SIGNIFICANCE: Textbooks rarely included knowledge and skills that are crucial to protect schoolchildren and their families from malaria. This study identified the need for improvement to textbook contents regarding malaria

Digital Gangrene:An Unusual Manifestation of Non-Hodgkin Lymphoma

BACKGROUND: Non-Hodgkin lymphomas (NHLs) comprise a group of haematologic malignancies with different histologic subtypes. The clinical picture varies from indolent to aggressive presentation and nodal (lymphadenopathy) to extranodal (central nervous system, gastrointestinal, cutaneous plaque, or ulcer) involvement. Digital gangrene is seldom reported. Here, we describe a patient with pain and blackening of all fingers and toes as presenting symptoms of NHL. Case Presentation. A 32-year-old male weaver had been smoking three to five cannabis-containing cigarettes daily for about ten years and methamphetamine four to five tablets daily for five years. He had no history of Raynaud's phenomenon, fever, cough, weight loss, skin rash, joint pain, and atherogenic or thrombogenic risk factors. We found normal blood pressure and absent peripheral pulses in arms and legs, dry gangrene of all fingers and toes, generalized lymphadenopathy, and hepatomegaly with ascites. The chest X-ray was normal, as were blood sugar, lipid profile, and hepatic and renal function. Rheumatoid factor, antinuclear and antiphospholipid antibodies, C-ANCA and P-ANCA, hepatitis B and C, and HIV were negative. CT abdomen revealed hepatosplenomegaly with multiple intra-abdominal lymphadenopathies. The peripheral angiogram showed 90-99% stenosis of radial and dorsalis pedis arteries with normal proximal vessels. Diagnosis of non-Hodgkin lymphoma was confirmed by histopathology of cervical lymph node (diffuse type), immunohistochemically subtyped as peripheral T cell lymphoma (not otherwise specified). The digital ischemia worsened despite cessation of cannabis and methamphetamine and starting CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) treatment, making amputation necessary. CONCLUSION: We present, to our knowledge, the first report of peripheral T cell lymphoma, NOS presenting with gangrene in all digits complicated by methamphetamine and cannabis abuse. This uncommon vascular manifestation of non-Hodgkin lymphoma may cause a diagnostic dilemma and delayed initiation of treatment

Isotherm, kinetic and modeling studies

Funding Information: Funding: The Deanship of Scientific Research at King Khalid University General Research Project under the grant number (R.G.P.2/138/42) and Taif University researchers supporting project number (TURSP–2020/157), Taif University, Taif, Saudi Arabia. Funding Information: Acknowledgments: The co‐author Ali E. Anqi would like to extend his appreciation to the Deanship of Scientific Research at King Khalid University for the support he received through General Re‐ search Project under the grant number (R.G.P.2/138/42). This work was supported by Taif Univer‐ sity researchers supporting project number (TURSP–2020/157), Taif University, Taif, Saudi Arabia. The first author was thankful to the Directorate of Minorities, Govt. of Karnataka for providing PhD fellowship to conduct the research. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.The first-ever use of halloysite nanotube (HNT), a relatively low-cost nanomaterial abun-dantly available with minor toxicity for removing brilliant green dye from aqueous media, is re-ported. The factors affecting adsorption were studied by assessing the adsorption capacity, kinetics, and equilibrium thermodynamic properties. All the experiments were designed at a pH level of around 7. The Redlich-Peterson isotherm model fits best amongst the nine isotherm models studied. The kinetic studies data confirmed a pseudo model of the second order. Robotic investigations pro-pose a rate-controlling advance being overwhelmed by intraparticle dispersion. The adsorbent fea-tures were interpreted using infrared spectroscopy and electron microscopy. Process optimization was carried out using Response Surface Methodology (RSM) through a dual section Fractional Fac-torial Experimental Design to contemplate the impact of boundaries on the course of adsorption. The examination of fluctuation (ANOVA) was utilized to consider the joined impact of the boundaries. The possibilities of the use of dye adsorbing HNT (“sludge”) for the fabrication of the composites using plastic waste are suggested.publishersversionpublishe

A recent study on remediation of direct blue 15 dye using halloysite nanotubes

R.G.P.2/138/42 TURSP–2020/157A set of lab‐scale experiments were designed and conducted to remedy Direct Blue 15 (DB15) dye using nontoxic halloysite nanotubes (HNT) with the view to be utilized in a textile industrial effluent (TIE). The DB15 adsorbed‐HNT “sludge” was used as a reinforcing agent and plas-tic waste to fabricate the composite. To advance the knowledge and further understand the chemical phenomena associated with DB15 adsorption on HNT, different factors like pH value, adsorbate initial concentration, adsorbent dosage, and temperature on the composite were affected experi-mentally tested. To estimate the adsorption capacity of HNT, nine isotherm models were applied, and it was identified that the Brouers–Sotolongo adsorption isotherm model represented the best accuracy for predicting the adsorption behavior of the HNT. Likewise, the pseudo‐second‐order reaction was the predominant mechanism for the overall rate of the multi‐step dye adsorption pro-cess. Additionally, it was demonstrated that the mass transfer during the process is diffusion‐con-trolled, and thermodynamic assessments showed that the process is physisorption.publishersversionpublishe