A dynamic clustering construction for wireless sensor networks

International audienceResearch in sensor networks has focused on development of energy efficient and secure infrastructures. In this article, we introduce a new approach to organize sensor networks in clusters in order to reduce energy dissipation. Our contribution is an heuristic to define the number of clusters and also an efficient manner to choose cluster heads by minimizing the distance between the cluster heads and its cluster nodes. Inspired from LEACH, a well-known TDMA cluster-based sensor network architecture, we introduce a new method for building and maintaining clusters using the paradigm of a soccer team. In this work, a new algorithm called OH-Kmeans, based on the Kmeans algorithm, is used to find dynamically the number of clusters and form them guaranteeing direct transmission between the cluster heads and cluster nodes

Clinical spectrum and severity of hemolytic anemia in glucose 6-phosphate dehydrogenase-deficient children receiving dapsone

Drug-induced acute hemolytic anemia led to the discovery of G6PD deficiency. However, most clinical data are from isolated case reports. In 2 clinical trials of antimalarial preparations containing dapsone (4,4′-diaminodiphenylsulfone; 2.5 mg/kg once daily for 3 days), 95 G6PD-deficient hemizygous boys, 24 G6PD-deficient homozygous girls, and 200 girls heterozygous for G6PD deficiency received this agent. In the first 2 groups, there was a maximum decrease in hemoglobin averaging -2.64 g/dL (range -6.70 to +0.30 g/dL), which was significantly greater than for the comparator group receiving artemether-lumefantrine (adjusted difference -1.46 g/dL; 95% confidence interval -1.76, -1.15). Hemoglobin concentrations were decreased by ≥ 40% versus pretreatment in 24/119 (20.2%) of the G6PD-deficient children; 13/119 (10.9%) required blood transfusion. In the heterozygous girls, the mean maximum decrease in hemoglobin was -1.83 g/dL (range +0.90 to -5.20 g/dL); 1 in 200 (0.5%) required blood transfusion. All children eventually recovered. All the G6PD-deficient children had the G6PD A- variant, ie, mutations V68MandN126D. Drug-induced acutehemolytic anemia in G6PD A- subjects can be life-threatening, depending on the nature and dosage of the drug trigger. Therefore, contrary to current perception, in clinical terms the A- type of G6PD deficiency cannot be regarded as mild. This study is registered at http://www.clinicaltrials.gov as NCT00344006 and NCT00371735. © 2012 by The American Society of Hematology

Spotlight on the role of the news media

The push by the PNG government for a 'responsible and accountable' media has put the country's industry in the public spotlight. Several seminars and debates have highlighted the role as a public watchdog.&nbsp

Miners 'Train' Journalists

This In Brief reports on the fourth annual Media Workshop (8–9 May 2014) sponsored by the Papua New Guinea (PNG) Chamber of Mines and Petroleum for journalists working in PNG’s mainstream media. The chamber is the peak representative body of the mining and petroleum industry, considered by many to be the backbone of the PNG economy.AusAI

Clinical spectrum and severity of hemolytic anemia in glucose 6-phosphate dehydrogenase-deficient children receiving dapsone

Drug-induced acute hemolytic anemia led to the discovery of G6PD deficiency. However, most clinical data are from isolated case reports. In 2 clinical trials of antimalarial preparations containing dapsone (4,4′-diaminodiphenylsulfone; 2.5 mg/kg once daily for 3 days), 95 G6PD-deficient hemizygous boys, 24 G6PD-deficient homozygous girls, and 200 girls heterozygous for G6PD deficiency received this agent. In the first 2 groups, there was a maximum decrease in hemoglobin averaging -2.64 g/dL (range -6.70 to +0.30 g/dL), which was significantly greater than for the comparator group receiving artemether-lumefantrine (adjusted difference -1.46 g/dL; 95% confidence interval -1.76, -1.15). Hemoglobin concentrations were decreased by ≥ 40% versus pretreatment in 24/119 (20.2%) of the G6PD-deficient children; 13/119 (10.9%) required blood transfusion. In the heterozygous girls, the mean maximum decrease in hemoglobin was -1.83 g/dL (range +0.90 to -5.20 g/dL); 1 in 200 (0.5%) required blood transfusion. All children eventually recovered. All the G6PD-deficient children had the G6PD A- variant, ie, mutations V68MandN126D. Drug-induced acutehemolytic anemia in G6PD A- subjects can be life-threatening, depending on the nature and dosage of the drug trigger. Therefore, contrary to current perception, in clinical terms the A- type of G6PD deficiency cannot be regarded as mild. This study is registered at http://www.clinicaltrials.gov as NCT00344006 and NCT00371735. © 2012 by The American Society of Hematology

The Impact of Retail Sector Delivery of Artemether-Lumefantrine on Effective Malaria Treatment of Children Under Five in Kenya

Background: With a low proportion of children receiving the first line treatment for suspected malaria, it has been proposed that artemisinin based combination therapy be subsidised in the private sector in order to improve affordability and access. This thesis presents an evaluation of a pilot subsidy mechanism in Western Kenya.Methods: The primary objective was to evaluate the impact of providing subsidized artemether-lumefantrine (AL) through trained retailers, on the coverage of prompt effective anti-malarial treatment for febrile children aged three to 59 months. I used a cluster-randomised, controlled design with nine control and nine intervention sublocations, equally distributed across three districts. Provider, mystery shopper and household cross-sectional surveys were conducted at baseline and one year later. Data were analysed based on cluster-level summaries, comparing control and intervention arms, while adjusting for covariates. On average details of 2,706 children and 564 retail outlets were captured per year.Results: Provider survey and mystery shopper data showed that at follow-up a significantly greater percentage of retailers stocked and dispensed AL, and knew that AL was the first line treatment for uncomplicated malaria in the intervention arm compared to the control. Significantly fewer retailers stocked antimalarial monotherapies. Household survey data showed that an average of 29% of children had experienced fever within the previous two weeks. Within this sample, the percentage receiving AL on the same day or following day of fever developing at follow-up was 25.0% points higher in the intervention arm than in the control arm, a statistically significant difference. However, adherence to dosing for AL purchased in the retail sector and advice given to caretakers by retailers remained unchanged post-intervention. Conclusion: Overall, subsidizing ACTs in the retail sector can significantly increase ACT coverage in rural areas. Further research is needed on ways to improve counselling and adherence as well as on the impact and cost-effectiveness of such an intervention at a national scale

Capacité du pourghère (JATROPHA CURCAS L.) à croître sur un sol dégradé et restaurer certaines de ses caractéristiques chimiques

La superficie des sols dégradés ne cesse de croître dans le monde. Au Gabon, cette dégradation des sols à grande échelle est majoritairement liée à l’action anthropique. Il est donc judicieux d’explorer des pistes de restauration des sols appauvris afin de pouvoir les utiliser en agriculture. Nous avons expérimenté pendant quatre ans l’une des méthodes modernes de restauration des sols, qui consiste à utiliser des plantes dites améliorantes tel que le pourghère (Jatropha curcas L.) qui a des effets positifs sur certaines propriétés physiques, chimiques et biologiques des sols et qui présente plusieurs vertus. Le pourghère présente l’avantage de reconstituer la matière organique du sol par la chute importante de ses feuilles et améliore ainsi les propriétés agronomiques des sols dégradés. Il possède des capacités pour la stabilisation physique des sols et peut régénérer leur fertilité en y fixant de l’azote atmosphérique dans la rhizosphère. C’est une plante résistante à la sécheresse, peu exigeante en eau et qui peut pousser presque partout, même sur les sols marginaux les plus pauvres. Toutes ces raisons justifient le choix du pourghère pour la restauration des sols dégradés. L’objectif général de cette thèse est d’abord de démontrer que le pourghère peut se multiplier sur un sol pauvre en éléments nutritifs, puis d’y suivre sa croissance, et de montrer qu’il est capable d’améliorer certaines caractéristiques chimiques de ce sol. Premièrement, il a été question de déterminer le meilleur mode de multiplication entre les graines et les boutures en déterminant les taux de germination et de survie, les temps de latence et la croissance juvénile des plantules. Ensuite, nous avons déterminé la capacité du pourghère à croître sur un sol dégradé, et enfin nous avons évalué le potentiel du pourghère à améliorer certaines caractéristiques chimiques des sols tropicaux dégradés. Les résultats de notre étude montrent que le taux de germination est de 97% pour les graines et 94% pour les boutures en semis en pot, contre respectivement 5% et 1,4% en semis direct. La hauteur et le diamètre au collet des plantules varient suivant l’effet combiné du temps et du type de matériel végétal et la production foliaire des plantules du J. curcas L, varie suivant le temps et suivant le type de matériel végétal. Après la transplantation, les résultats révèlent que la croissance en hauteur des plantes de J. curcas est influencée de manière très significative par l’interaction du type de matériel végétal et de l’écartement de semis et que le diamètre au collet s’accroit avec le temps. L’émission des feuilles est active de novembre à décembre et est suivi d’une perte considérable et continue des feuilles le reste du temps d’observation. Les résultats d’analyse des sols montrent que le J. curcas améliore les concentrations en carbone et en azote du sol et qu’il régule le pH. La concentration en carbone (C) sur les deux profondeurs et en azote (N) à la surface, ainsi que le pH du sol sur les deux profondeurs sont influencés de manière significative suivant l’âge de la plantation. Les plantes issues des boutures ont une meilleure amélioration du pH que celles issues des graines. Les résultats de cette étude mettent en exergue les questions de restauration des sols tropicaux dégradés en utilisant les plantes améliorantes. Nos résultats montrent que le J. curcas améliore les propriétés chimiques des sols tropicaux dégradés par la surexploitation intensive et successive de cacaoyers et d’hévéas. Cependant, des recherches futures permettrons de vérifier si les propriétés biologiques et physiques des sols sont également concernées par cette amélioration

Balancing children's right to education and criminal responsibility in arson cases in Kenya

Submitted in partial fulfilment of the requirements of the Bachelor of Laws Degree, Strathmore University Law SchoolThe arson incident at Moi Girls Nairobi was a wake-up call to the Ministry of Education. Kenyans watched as firemen struggled to put out the raging fire. 9 students died. Property was lost to the fire. Many fires had been reported, many more came thereafter. This prompted various schools to take measures to insure themselves against future fires. Many reasons have been given for what is now a phenomenon, including a lack of awareness and support for student with mental health issues and the fact that the students are using the fire as political action. The Kenyan courts in determining these matters have increasingly ordered that the students suspected of the incidents of arson be accepted back in the schools.1 This study seeks to find out the role of the Kenyan courts and other stakeholders in the mitigation of arson; from the backing of the right to property and the right to education to the creation of a balance. It also seeks to investigate the role of the right of property in encouraging arson and in its mitigation or eventual curbin

Frequency of glucose-6-phosphate dehydrogenase deficiency in malaria patients from six African countries enrolled in two randomized anti-malarial clinical trials

<p>Abstract</p> <p>Background</p> <p>Glucose-6-phosphate dehydrogenase (G6PD) deficiency is common in populations living in malaria endemic areas. G6PD genotype and phenotype were determined for malaria patients enrolled in the chlorproguanil-dapsone-artesunate (CDA) phase III clinical trial programme.</p> <p>Methods</p> <p>Study participants, aged > 1 year, with microscopically confirmed uncomplicated <it>Plasmodium falciparum </it>malaria, and haemoglobin ≥ 70 g/L or haematocrit ≥ 25%, were recruited into two clinical trials conducted in six African countries (Burkina Faso, Ghana, Kenya, Nigeria, Tanzania, Mali). G6PD genotype of the three most common African forms, G6PD*B, G6PD*A (A376G), and G6PD*A- (G202A, A542T, G680T and T968C), were determined and used for frequency estimation. G6PD phenotype was assessed qualitatively using the NADPH fluorescence test. Exploratory analyses investigated the effect of G6PD status on baseline haemoglobin concentration, temperature, asexual parasitaemia and anti-malarial efficacy after treatment with CDA 2/2.5/4 mg/kg or chlorproguanil-dapsone 2/2.5 mg/kg (both given once daily for three days) or six-dose artemether-lumefantrine.</p> <p>Results</p> <p>Of 2264 malaria patients enrolled, 2045 had G6PD genotype available and comprised the primary analysis population (1018 males, 1027 females). G6PD deficiency prevalence was 9.0% (184/2045; 7.2% [N = 147] male hemizygous plus 1.8% [N = 37] female homozygous), 13.3% (273/2045) of patients were heterozygous females, 77.7% (1588/2045) were G6PD normal. All deficient G6PD*A- genotypes were A376G/G202A. G6PD phenotype was available for 64.5% (1319/2045) of patients: 10.2% (134/1319) were G6PD deficient, 9.6% (127/1319) intermediate, and 80.2% (1058/1319) normal. Phenotype test specificity in detecting hemizygous males was 70.7% (70/99) and 48.0% (12/25) for homozygous females. Logistic regression found no significant effect of G6PD genotype on adjusted mean baseline haemoglobin (p = 0.154), adjusted mean baseline temperature (p = 0.9617), or adjusted log mean baseline parasitaemia (p = 0.365). There was no effect of G6PD genotype (p = 0.490) or phenotype (p = 0.391) on the rate of malaria recrudescence, or reinfection (p = 0.134 and p = 0.354, respectively).</p> <p>Conclusions</p> <p>G6PD deficiency is common in African patients with malaria and until a reliable and simple G6PD test is available, the use of 8-aminoquinolines will remain problematic. G6PD status did not impact baseline haemoglobin, parasitaemia or temperature or the outcomes of anti-malarial therapy.</p> <p>Trial registration</p> <p>Clinicaltrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00344006">NCT00344006</a> and <a href="http://www.clinicaltrials.gov/ct2/show/NCT00371735">NCT00371735</a>.</p

Roundtable discussion: what is the future role of the private sector in health?

Background: The role for the private sector in health remains subject to much debate, especially within the context of achieving universal health coverage. This roundtable discussion offers diverse perspectives from a range of stakeholders – a health funder, a representative from an implementing organization, a national-level policy-maker, and an expert working in a large multi-national company – on what the future may hold for the private sector in health. Discussion: The first perspective comes from a health funder, who argues that the discussion about the future role of the private sector has been bogged down in language. He argues for a ‘both/and’ approach rather than an ‘either/or’ when it comes to talking about health service provision in low- and middle-income countries. The second perspective is offered by an implementer of health insurance in sub-Saharan Africa. The piece examines the comparative roles of public sector actors, private sector actors and funding agencies, suggesting that they must work together to mobilize domestic resources to fund and deliver health services in the longer term. Thirdly, a special advisor working in the federal government of Nigeria considers the situation in that country. He notes that the private sector plays a significant role in funding and delivering health services there, and that the government must engage the private sector or forever be left behind. Finally, a representative from a multi-national pharmaceutical corporation gives an overview of global shifts that are creating opportunities for the private sector in health markets. Summary: Overall, the roundtable discussants agree that the private sector will play an important role in future health systems. But we must agree a common language, work together, and identify key issues and gaps that might be more effectively filled by the private sector.DFI