Observation of Ground-State Two-Neutron Decay

Neutron decay spectroscopy has become a successful tool to explore nuclear properties of nuclei with the largest neutron-to-proton ratios. Resonances in nuclei located beyond the neutron dripline are accessible by kinematic reconstruction of the decay products. The development of two-neutron detection capabilities of the Modular Neutron Array (MoNA) at NSCL has opened up the possibility to search for unbound nuclei which decay by the emission of two neutrons. Specifically this exotic decay mode was observed in 16Be and 26O.Comment: To be published in Acta Physica Polonica

Exploring the neutron dripline two neutrons at a time: The first observations of the 26O and 16Be ground state resonances

The two-neutron unbound ground state resonances of $^{26}$O and $^{16}$Be were populated using one-proton knockout reactions from $^{27}$F and $^{17}$B beams. A coincidence measurement of 3-body system (fragment + n + n) allowed for the decay energy of the unbound nuclei to be reconstructed. A low energy resonance, $<$ 200 keV, was observed for the first time in the $^{24}$O + n + n system and assigned to the ground state of $^{26}$O. The $^{16}$Be ground state resonance was observed at 1.35 MeV. The 3-body correlations of the $^{14}$Be + n + n system were compared to simulations of a phase-space, sequential, and dineutron decay. The strong correlations in the n-n system from the experimental data could only be reproduced by the dineutron decay simulation providing the first evidence for a dineutron-like decay.Comment: Invited Talk given at the 11th International Conference on Nucleus-Nucleus Collisions (NN2012), San Antonio, Texas, USA, May 27-June 1, 2012. To appear in the NN2012 Proceedings in Journal of Physics: Conference Series (JPCS

Seasonal and geographic differences in treatment-seeking and household cost of febrile illness among children in Malawi

BACKGROUND: Households in malaria endemic countries experience considerable costs in accessing formal health facilities because of childhood malaria. The Ministry of Health in Malawi has defined certain villages as hard-to-reach on the basis of either their distance from health facilities or inaccessibility. Some of these villages have been assigned a community health worker, responsible for referring febrile children to a health facility. Health facility utilization and household costs of attending a health facility were compared between individuals living near the district hospital and those in hard-to-reach villages. METHODS: Two cross-sectional household surveys were conducted in the Chikhwawa district of Malawi; one during each of the wet and dry seasons. Half the participating villages were located near the hospital, the others were in areas defined as hard-to-reach. Data were collected on attendance to formal health facilities and economic costs incurred due to recent childhood febrile illness. RESULTS: Those living in hard-to-reach villages were less likely to attend a formal health facility compared to those living near the hospital (Dry season: OR 0.35, 95%CI0.18-0.67; Wet season: OR 0.46, 95%CI0.27-0.80). Analyses including community health workers (CHW) as a source of formal health-care decreased the strength of this relationship, and suggested that consulting a CHW may reduce attendance at health facilities, even if indicated. Although those in hard-to-reach villages were still less likely to attend in both the dry (OR 0.53, 95%CI 0.25-1.11) and wet (OR 0.60, 95%CI 0.37-0.98) seasons. Household costs for those who attended a health facility were greater for those in HTR villages (Dry: USD5.24; Wet: USD5.60) than for those living near the district hospital (Dry: USD3.45; Wet: USD4.46). CONCLUSION: Those living in hard-to-reach areas were less likely to attend a health facility for a childhood febrile event and experienced greater associated household costs. Consulting CHWs was infrequent, but appeared to reduce attendance at a health facility, even when indicated. Health service planners must consider geographic and financial barriers to accessing public health facilities in designing appropriate interventions

The Economic Benefits Resulting from the First 8 Years of the Global Programme to Eliminate Lymphatic Filariasis (2000–2007)

Lymphatic filariasis (LF), commonly known as ‘elephantiasis’, is one of the world's most debilitating infectious diseases. In 83 countries worldwide, more than 1.3 billion people are at risk of infection with an estimated 120 million individuals already infected. A recent publication reviewing the health impact of the first 8 years of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) demonstrated the enormous health benefits achieved in populations receiving annual mass drug administration (MDA), as a result of infection prevented, disease progression halted, and ancillary treatment of co-infections. To date, however, no studies have estimated the economic value of these health benefits, either to the individuals or the societies afflicted with LF. Our study estimates that US$21.8 billion will be gained among individuals benefitting from just the first 8 years of the Global Programme, and an additional US$2.2 billion will be saved by the health systems of endemic countries. Treating endemic populations is possible at very low cost – particularly because of the generous drug donations from two pharmaceutical companies – but results in enormous economic benefits. Findings from this study yield a much clearer understanding the GPELF's full economic impact and strengthen the conviction that it is a ‘best buy’ in global health

Comparison of antioxidant activity, Phenolic and Flavonoid contents of selected medicinal plants in Sri Lanka

Oxidative stress related diseases are as a result of accumulation of free radicals in the cellular organs. Plant based antioxidants play a defensive role by preventing the generation of free radicals and therefore the main focus of this study was to screen twenty five Sri Lankan medicinal plants for comparison of antioxidant capacity. Aqueous extracts of twenty five plants were screened for antioxidant activity by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Six plants that gave high antioxidant activity Terminalia chebula Retz., Punica granatum L., Flueggea leucopyrus Willd., Cassia fistula L., Piper betle L. and Phyllanthus amarus were selected for further analysis. Methanol extracts of the selected plants were subjected to assess IC50 by DPPH assay. Total phenolic and flavonoid contents were analyzed by Folin Ceocalteu method and Aluminium Colorimetric method respectively. Statistical analysis was done by Minitab 17 package using regression analysis techniques to identify the effect of IC50 by phenolics and flavonoids. Seeds of T. chebula Retz. showed high antioxidant activity with 102 mg/ml of IC50 value. Antioxidant activity of rest of the plants in the descending order was F. leucopyrus Willd. (twigs) &gt; C. fistula L. (bark) &gt; P.granatum L. (leaves) &gt; P. betle L. (leaves) &gt;P. amarus (twigs). The relationship between IC50 by phenolic and flavonoid content was statistically significant. Further IC50 has a strong negative relationship between phenolics and flavonoids. Data from present study revealed that Terminalia chebula Retz., Punica granatum L., Flueggea leucopyrus Willd., Cassia fistula L., Piper betle L. and Phyllanthus amarus possess high antioxidant capacity compared to other medicinal plants

Evaluation of immunomodulatory effect of Ranahamsa Rasayanaya – A Sri Lankan classical rasayana drug, on experimental animals

Immunity plays a key role in maintaining the health of an individual. Therefore, the rational modulation of the immunity through psycho-neuro-endocrine-immune (PNI) axis is useful for the prevention as well as for the curing of the diseases. As immunomodulation is a parameter for evaluation of the rasayana effect of a drug, the same has been studied to assess the rasayana effect of Ranahamsa Rasayanaya (RR). Experimental models such as antibody formation against sheep red blood cells (SRBC) and cell mediated immunity (CMI) have been carried out befitting on Wistar strain albino rats to determine the immunomodulatory effect plus rasayana effect of RR. Statistically significant increase in body weight, nonsignificant increase in antibody formation against SRBC, highly significant decrease in CMI were observed in the treatment groups, when compared to the standard control group. These results show the probable immunomodulatory and anabolic activities of the test drug. Outcome of these studies validate the strong rasayana effect of the test drug claimed by the traditional practitioners of Sri Lanka

Surface modification of natural vein graphite for the anode application in Li-ion rechargeable batteries

Natural vein graphite with high purity and crystallinity is seldom used as anode material in lithium-ion rechargeable batteries (LIB) due to impurities and inherent surface structure. This study focuses on improving the surface properties of purified natural vein graphite surface by employing mild chemical oxidation. Needle-platy graphite sample with initial average carbon percentage of 99.83% was improved to 99.98% after treatment with 5 vol.% HCl. Surface modification of purified graphite was done by chemical oxidation with (NH4)(2)S2O8 and HNO3. Fourier-transform infrared spectra of graphite after chemical indicating surface oxidation of graphite surface. X-ray diffraction and scanning electron microscopic studies show the improvement of graphite structure without modification of crystalline structure. Electrochemical performance of lithium-ion cell assembled with developed anode material shows noticeable improvement of the reversible capacity and coulombic efficiency in the first cycle and cycling behavior after surface modification