The dominant Anopheles vectors of human malaria in the Asia-Pacific region: occurrence data, distribution maps and bionomic précis

<p>Abstract</p> <p>Background</p> <p>The final article in a series of three publications examining the global distribution of 41 dominant vector species (DVS) of malaria is presented here. The first publication examined the DVS from the Americas, with the second covering those species present in Africa, Europe and the Middle East. Here we discuss the 19 DVS of the Asian-Pacific region. This region experiences a high diversity of vector species, many occurring sympatrically, which, combined with the occurrence of a high number of species complexes and suspected species complexes, and behavioural plasticity of many of these major vectors, adds a level of entomological complexity not comparable elsewhere globally. To try and untangle the intricacy of the vectors of this region and to increase the effectiveness of vector control interventions, an understanding of the contemporary distribution of each species, combined with a synthesis of the current knowledge of their behaviour and ecology is needed.</p> <p>Results</p> <p>Expert opinion (EO) range maps, created with the most up-to-date expert knowledge of each DVS distribution, were combined with a contemporary database of occurrence data and a suite of open access, environmental and climatic variables. Using the Boosted Regression Tree (BRT) modelling method, distribution maps of each DVS were produced. The occurrence data were abstracted from the formal, published literature, plus other relevant sources, resulting in the collation of DVS occurrence at 10116 locations across 31 countries, of which 8853 were successfully geo-referenced and 7430 were resolved to spatial areas that could be included in the BRT model. A detailed summary of the information on the bionomics of each species and species complex is also presented.</p> <p>Conclusions</p> <p>This article concludes a project aimed to establish the contemporary global distribution of the DVS of malaria. The three articles produced are intended as a detailed reference for scientists continuing research into the aspects of taxonomy, biology and ecology relevant to species-specific vector control. This research is particularly relevant to help unravel the complicated taxonomic status, ecology and epidemiology of the vectors of the Asia-Pacific region. All the occurrence data, predictive maps and EO-shape files generated during the production of these publications will be made available in the public domain. We hope that this will encourage data sharing to improve future iterations of the distribution maps.</p

Taking stock of 10 years of published research on the ASHA programme: Examining India’s national community health worker programme from a health systems perspective

Background: As India’s accredited social health activist (ASHA) community health worker (CHW) programme enters its second decade, we take stock of the research undertaken and whether it examines the health systems interfaces required to sustain the programme at scale. Methods: We systematically searched three databases for articles on ASHAs published between 2005 and 2016. Articles that met the inclusion criteria underwent analysis using an inductive CHW–health systems interface framework. Results: A total of 122 academic articles were identified (56 quantitative, 29 mixed methods, 28 qualitative, and 9 commentary or synthesis); 44 articles reported on special interventions and 78 on the routine ASHA program. Findings on special interventions were overwhelmingly positive, with few negative or mixed results. In contrast, 55% of articles on the routine ASHA programme showed mixed findings and 23% negative, with few indicating overall positive findings, reflecting broader system constraints. Over half the articles had a health system perspective, including almost all those on general ASHA work, but only a third of those with a health condition focus. The most extensively researched health systems topics were ASHA performance, training and capacity-building, with very little research done on programme financing and reporting, ASHA grievance redressal or peer communication. Research tended to be descriptive, with fewer influence, explanatory or exploratory articles, and no predictive or emancipatory studies. Indian institutions and authors led and partnered on most of the research, wrote all the critical commentaries, and published more studies with negative results. Conclusion: Published work on ASHAs highlights a range of small-scale innovations, but also showcases the challenges faced by a programme at massive scale, situated in the broader health system. As the programme continues to evolve, critical comparative research that constructively feeds back into programme reforms is needed, particularly related to governance, intersectoral linkages, ASHA solidarity, and community capacity to provide support and oversight

Structural and magnetic properties of ZnXCo1-XFe2O4 nanoparticles: Nonsaturation of magnetization

ZnXCo1-XFe2O4 nanoparticles were synthesized by sol-gel method and were annealed at two different temperatures; 500 degrees C and 900 degrees C in air for 2 h. Structural studies were carried out by X-ray diffraction and Fourier transformed infrared spectroscopy. The crystallite size didn't show any variation with the increase in Zn2+ concentration and was increased after annealing. The magnetization value at 300 K for the as-prepared samples increased from 53 emu/g to 60 emu/g when Zn2+ concentration increased from x= 0 to 0.2 and then it decreased to 11 emu/g for x=1. Similar magnetic behavior was also observed for the annealed samples with a peak at x=0.2. A very high magnetization value of 116 emu/g at 60 K was observed for the 900 degrees C annealed sample with x=0.4. The coercivity decreased monotonically with the increase in the Zn2+ concentration for both the as-prepared and the annealed samples. The magnetization and coercivity values were observed to be enhanced with the decrease in measurement temperature. The nonsaturation behavior of the magnetic hysteresis loops of these nanoparticle samples observed for all compositions and temperatures was studied by the method of approach to saturation by fitting M(H)=M(infinity) [ 1-(H*/H) (1/2)] to the high field data of the initial curve from 20 kOe to 30 kOe. It was observed that H* value which is the measure of the nonsaturation increased with the increase in the Zn2+ concentration. The observed magnetic properties in these nanoparticle samples can be ascribed to the changed cation distribution in the spinel structure and to the decrease of Co2+ concentration

Exchange spring like magnetic behavior in cobalt ferrite nanoparticles

Cobalt ferrite nanoparticles were prepared by sol-gel technique and were annealed at 900 degrees C in air for 2 h. Structural properties were studied by X-ray diffraction, Raman spectroscopy and Fourier transformed infrared spectroscopy. Scanning electron microscopy and transmission electron microscopy studies show presence of mostly two different sizes of grains in these samples. Magnetization value of 58.36 emu/g was observed at 300 K for the as prepared sample and an enhanced magnetization close to the bulk value of 80.59 emu/g was observed for the annealed sample. At 10 K a two stepped hysteresis loop showing exchange spring magnetic behavior was observed accompanied by very high values of coercivity and remanence. Two clear peaks were observed in the derivative of demagnetization curve in the as prepared sample where as two partially overlapped peaks were observed in the annealed sample. The observed magnetic properties can be understood on the basis of the grain size and their distribution leading to the different types of intergranular interactions in these nanoparticles. (C) 2015 Elsevier B.V. All rights reserved

Tailoring magnetic properties of cobalt ferrite nanoparticles by different divalent cation substitution

Different divalent cation substituted Co-ferrite (MXCo1-XFe2O4, where M = Mg2+, Ni2+, Cu2+, Zn2+, with x = 0.20 and 0.75) nanoparticles were synthesized by sol-gel method and were annealed at 900 A degrees C in air. After annealing, grain growth was observed for all the samples. With the substitution of Mg2+, Ni2+ and Cu2+ with x = 0.20, the magnetization of the as-prepared and the annealed samples was decreased from that of the Co-ferrite whereas Zn2+ substitution enhanced the magnetization. The highest magnetization values of 79.9 and 92.9 emu/g at 300 and 60 K respectively were observed for the Zn2+ substituted annealed sample with x = 0.20. For higher concentration of x = 0.75, the magnetization value was further decreased in all the samples and the lowest magnetization value of 5.1 emu/g was observed in the Zn2+ substituted annealed sample with x = 0.75 at 300 K. The coercivity was reduced in the samples except for the Cu2+ substituted sample. In the Cu2+ substituted sample with x = 0.75, the highest coercivity of 1.43 kOe at 300 K was observed after annealing. The changed cation distribution in the spinel structure, ionic magnetic moment and anisotropy compared to the Co2+ in these nanomaterials can explain the observed magnetic properties

Stability-indicating HPLC method for simultaneous determination of aspirin and prasugrel

A simple, sensitive, specific, accurate, and stability-indicating reversed phase high performance liquid chromatographic method was developed for the simultaneous determination of aspirin and prasugrel, using a Kromasil 100 C 18 (150×4.6 mm, 5 μ) column and a mobile phase composed of acetonitrile:methanol:water (30:10:60, v/v), pH 3.0 adjusted with o-phosphoric acid. The retention times of aspirin and prasugrel were found to be 3.28 min and 6.61 min, respectively. Linearity was established for aspirin and prasugrel in the range of 15-150 and 2-20 μg/ml, respectively. The percentage recoveries of aspirin and prasugrel were found to be in the range of 99.34-100.32% and 98.92-102.09%, respectively. Both the drugs were subjected to acid, alkali and neutral hydrolysis, oxidation, dry heat, and UV degradation. The degradation studies indicated aspirin to be more susceptible to alkaline hydrolysis, while prasugrel to be more susceptible to neutral hydrolysis. The degradation products were well resolved from the pure drug with significant differences in their retention time values. This method can be successfully employed for simultaneous quantitative analysis of aspirin and prasugrel in bulk drugs and formulations