Role of polyvinyl pyrrolidone as a capping agent in the synthesis of magnetite (Fe3O4) nanoparticles

Uncapped magnetite (Fe3O4) and magnetite capped with polyvinyl pyrrolidone (PVP) (Fe3O4-PVP) have been synthesized by a rapid, cost effective aqueous precipitation method. The nanoparticles are characterized by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and UV spectroscopy. The role of PVP as a capping agent in the synthesis of magnetite nanoparticles has been investigated. Thermal stability and surface charge of the nanoparticles have been characterized by thermogravimetric analysis, differential scanning calorimetry (DSC) and zeta potential measurements. Results suggest that PVP as a capping agent reduces the grain size, regularizes the shape, and increases the crystallinity of Fe3O4 nanoparticles. Thermal stability and surface charge of Fe3O4-PVP nanoparticles are also significantly higher as compared to the uncapped Fe3O4 nanoparticles. Magnetic characterization by vibrating sample magnetometry of both Fe3O4 and Fe3O4-PVP nanoparticles indicates the superparamagnetic behavior of the nanoparticles.

Efficacy of two artemisinin-based combinations for the treatment of malaria in pregnancy in India: a randomized controlled trial.

BACKGROUND: In India, the recommended first-line treatment for malaria in the second and third trimester of pregnancy is artesunate + sulfadoxine-pyrimethamine (AS+SP). However, data on safety and efficacy of artemisinin-based combination therapy (ACT) in pregnancy is limited. This study assessed the safety and efficacy of AS+SP and artesunate + mefloquine (AS+MQ) for treatment of Plasmodium falciparum in pregnancy in India. METHODS: This open-label, randomized clinical trial was conducted from October 2010 to December 2013 at three sites in India (Ranchi and Jamshedpur in Jharkhand state, and Rourkela in Odisha state). Pregnant women in the second or third trimester who had P. falciparum mono-infection of any parasite density with or without fever were randomized to receive AS+SP or AS+MQ. Blood slides and filter paper samples for Polymerase Chain Reaction (PCR) were collected on days 0, 1, 2, 3, 14, 21, 28, 42 and 63 post treatment. Women were followed up at delivery and at day 42 postpartum. FINDINGS: Two hundred and forty-eight women of 7064 pregnant women (3.5%) who were screened at monthly antenatal clinics had a P. falciparum mono-infection and were randomized to receive AS+SP (125) or AS+MQ (123) and all of these women were included in the intention to treat (ITT) analysis. The primary endpoint of an adequate clinical and parasite response (ACPR) on day 63 was not available for 9 women who were counted as treatment failure in the ITT analysis. In the ITT population, the ACPR was 121/125 (96.8%; 95% Confidence interval (CI) 92.0-99.1%) in the AS+SP group and 117/123 (95.1%; 95% CI 89.7-98.2) in the AS+MQ group. Among the 239 women (121 from the AS+SP arm and 118 from the AS+MQ arm) who completed the day 63 follow up (per protocol analysis) the ACPR was 100% in the AS+SP group and 99.2% (117/118) in the AS+MQ group. There were five serious adverse events (SAE) among pregnant women (4 in the AS+SP group and 1 in the AS+MQ group) and 13 fetal/neonatal SAEs (7 in the AS+SP group and 6 in the AS+MQ) but none of them were related to the study drugs. A higher proportion of women in the AS+MQ arm reported vomiting within 7 days post-treatment than did women in the AS+SP arm (6.9 vs. 1.6%; p = 0.001). CONCLUSION: Both AS+SP and AS+MQ are safe and effective for treatment of uncomplicated falciparum malaria in pregnancy in India. Trial registration CTRI This study is registered with Clinical Trial Registry India (CTRI), number CTRI/2009/091/001055. Date of Registration 11 January 2010, http://ctri.nic.in/Clinicaltrials/pmaindet2.php?trialid=1185&EncHid=&userName=anvikar

Diarrhea, Pneumonia, and Infectious Disease Mortality in Children Aged 5 to 14 Years in India

Background: Little is known about the causes of death in children in India after age five years. The objective of this study is to provide the first ever direct national and sub-national estimates of infectious disease mortality in Indian children aged 5 to 14 years. Methods: A verbal autopsy based assessment of 3 855 deaths is children aged 5 to 14 years from a nationally representative survey of deaths occurring in 2001–03 in 1?1 million homes in India. Results: Infectious diseases accounted for 58 % of all deaths among children aged 5 to 14 years. About 18 % of deaths were due to diarrheal diseases, 10 % due to pneumonia, 8 % due to central nervous system infections, 4 % due to measles, and 12 % due to other infectious diseases. Nationally, in 2005 about 59 000 and 34 000 children aged 5 to 14 years died from diarrheal diseases and pneumonia, corresponding to mortality of 24?1 and 13?9 per 100 000 respectively. Mortality was nearly 50 % higher in girls than in boys for both diarrheal diseases and pneumonia. Conclusions: Approximately 60 % of all deaths in this age group are due to infectious diseases and nearly half of these deaths are due to diarrheal diseases and pneumonia. Mortality in this age group from infectious diseases, and diarrhea i

Formation of amorphous carbon bearing hard phase in nitrogen ion implanted steel-route of tribological improvement

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Tribological properties of nitrogen ion implanted steel

Nitrogen ions (N⁺) with three different doses were implanted on the AISI 304 LN steel samples under high vacuum at room temperature. Dose dependent morphological and structural changes were observed in the specimen. Structural changes were triggered by formation of nitrides; irradiation induced surface segregation of carbon and deposition of amorphous carbon (a-C) by the cracking of hydrocarbons during implantation from oil diffusion pump. Morphological and structural changes were found to influence nano-mechanical and tribological properties of ion implanted surfaces. The nano-indentation hardness was found to increase to 10.26 GPa with highest N⁺ ion dose due to formation of surface nitrides and amorphous carbon. Frictional force was found to decrease with increase in N+ ion dose and a minimum value of 0.078 N was obtained at higher dose presumably due to the formation of amorphous graphite like phase. In addition, amorphous diamond like carbon on the implanted surface can be contributing facts for high hardness. At higher dose, both deformation induced damage and wear rate (2.4 × 10⁻⁷ mm³/Nm) were found to be minimum