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Lithium ion batteries play a crucial role in terms of good rechargeability, long cycles and higher shelf life. For the fabrication of such a Li ion battery, properties of cathode material can be engineered keeping anode and electrolyte fixed. In the present work, lithium iron phosphate (LiFePO) has been utilized as cathode material and the properties of LiFePO have been tuned by doping manganese (Mn). LiFePO and different concentrations of Mn doped LiFePO were prepared by solid state route. X-Ray diffraction and Raman studies were performed to confirm the formation of LiFePO and Mn doped LiFePO in olivine structure. Cyclic voltammetry studies revealed maximum peak oxidation current (2.96 mA) and largest surface coverage (0.066 nanoMoles/cm) for the LiFePO doped with 15% Mn (LiMnFePO). AC-conductivity study was carried out for different frequencies at room temperature. The conductivity parameters estimated using Almond and West formalism support the cyclic voltammetry results. Ion-hopping rate ( ω ) and charge carrier concentration ( K) maximize for 15% Mn doping ( ω : 582974.48719 Hz; K: 2.62447 × 10) and drop on either increasing ( ω : 167134.73521 Hz; K: 1.25647 × 10) or decreasing ( ω : 130726.49084 Hz; K: 2.52435 × 10) the Mn doping. The increase till 15% Mn doping has been attributed to the increase in unit cell volume with Mn doping while the sudden decrease at 20% Mn doping is due to dominance of back-hopping mechanism. The results clearly indicate that 15% Mn doped LiFePO is the most appropriate for the realization of a cathode for Li-ion battery. [ABSTRACT FROM AUTHOR]

Context: Providing oral health education in schools helps the children to develop personal skills, provide knowledge about oral health and promotes positive attitudes and health behaviours. Aim: The aim and objective of the study was to assess the change in knowledge attitude and practices(KAP) in oral health, following the oral heath education amongst the school children of Sundernagar city in Himachal Pradesh, India. Design: Cross sectional study Material and Method: The study was carried out on a total 649 children in the age range of 7-14 years selected randomly from different schools. KAP regarding oral health was recorded at baseline and after six months following the oral health education lectures and practical demonstrations. The pre and post data on oral health KAP were collected by means of a selfadministered Questionnaire. Statistical significance was determined by Chi-square test. Results. At baseline 39.1% were brushing twice which was increased to 76.9% after six months. Knowledge regarding various dental diseases improved from 9.2% to 80.6%. Increase from 9.5% to 92% and 26% to 98.3% was observed regarding the role of fluoride in dental diseases and for the importance of deciduous teeth respectively. Conclusion. Oral health education lectures are effective in changing the KAP about oral health of the children as well as in preventing and controlling the common dental diseases. [ABSTRACT FROM AUTHOR]

Rationale: Pulmonary nontuberculous mycobacterial (PNTM) disease is increasing, but predisposing features have been elusive.Objectives: To prospectively determine the morphotype, immunophenotype, and cystic fibrosis transmembrane conductance regulator genotype in a large cohort with PNTM.Methods: We prospectively enrolled 63 patients with PNTM infection, each of whom had computerized tomography, echocardiogram, pulmonary function, and flow cytometry of peripheral blood. In vitro cytokine production in response to mitogen, LPS, and cytokines was performed. Anthropometric measurements were compared with National Health and Nutrition Examination Survey (NHANES) age- and ethnicity-matched female control subjects extracted from the NHANES 2001-2002 dataset.Measurements and Main Results: Patients were 59.9 (+/-9.8 yr [SD]) old, and 5.4 (+/-7.9 yr) from diagnosis to enrollment. Patients were 95% female, 91% white, and 68% lifetime nonsmokers. A total of 46 were infected with Mycobacterium avium complex, M. xenopi, or M. kansasii; 17 were infected with rapidly growing mycobacteria. Female patients were significantly taller (164.7 vs. 161.0 cm; P < 0.001) and thinner (body mass index, 21.1 vs. 28.2; P < 0.001) than matched NHANES control subjects, and thinner (body mass index, 21.1 vs. 26.8; P = 0.002) than patients with disseminated nontuberculous mycobacterial infection. A total of 51% of patients had scoliosis, 11% pectus excavatum, and 9% mitral valve prolapse, all significantly more than reference populations. Stimulated cytokine production was similar to that of healthy control subjects, including the IFN-gamma/IL-12 pathway. CD4(+), CD8(+), B, and natural killer cell numbers were normal. A total of 36% of patients had mutations in the cystic fibrosis transmembrane conductance regulator gene.Conclusions: Patients with PNTM infection are taller and leaner than control subjects, with high rates of scoliosis, pectus excavatum, mitral valve prolapse, and cystic fibrosis transmembrane conductance regulator mutations, but without recognized immune defects. [ABSTRACT FROM AUTHOR]

Background: Exercise-induced hypoxemia is frequent in patients with lymphangioleiomyomatosis (LAM) and could be associated with pulmonary hypertension. The aims of this study were to determine the prevalence of pulmonary hypertension in patients with LAM, to identify physiologic parameters associated with its occurrence, and to evaluate the effect of oxygen on response to exercise.Methods: Studies were performed in 120 patients. Complete data, including exercise echocardiography, pulmonary function testing, and standard cardiopulmonary exercise testing, were obtained in 95 patients.Results: Resting pulmonary artery pressure (PAP) was 26+/-0.7 mm Hg (mean+/-SEM). Eight patients had pulmonary hypertension (43+/-3 mm Hg), and two patients had right ventricular dilatation. Ninety-five patients exercised (room air, n=64; oxygen, n=31) to a power of 58+/-2 W (49% of predicted) and an estimated peak oxygen uptake of 938+/-30 mL/min (56% of predicted). Sixty-one patients had a decline in arterial oxygen saturation (SaO2)>3%, and 56 patients had an elevation in PAP>40 mm Hg. Peak exercise PAP was negatively correlated with exercise Sao2 (p=0.0005). Multivariate analysis showed that exercise SaO2 was the best predictor of exercise PAP (p=0.012).Conclusions: Although resting pulmonary hypertension is rare in patients with LAM, a rise in PAP at low exercise levels occurs frequently, in part related to exercise-induced hypoxemia. Optimization of oxygen administration during activities of daily living should be undertaken in patients with LAM to prevent hypoxemia and exercise-induced pulmonary hypertension. [ABSTRACT FROM AUTHOR]

The paper reports the development of compression moulded pre-localized graphite/polyvinyl chloride (graphite/PVC) segregated composites with different concentrations of graphite and their application to the shield effectiveness of electromagnetic radiation in the X-band frequency range 8-12 GHz. The incorporation of graphite is related to the formation of conducting channels. It is found that conducting channels are formed above 3 wt. % of graphite. The electrical conductivity is also found to be strongly dependent on the graphite content, and the data are analysed using a percolation model. Variations in SE with graphite loading, due to changes in the conductivity of the composite, have been investigated [ABSTRACT FROM AUTHOR]

The impaction of a maxillary permanent first molar is rare. This present case was interesting because the tooth was not erupted into the oral cavity for more than six years. It was vertical and covered with a thick band of mucosa and bone. We did surgical exposure of the tooth as soon as possible and maintained the patency of the wound for its eruption. If not treated early it may lead to development of dentigerous cyst or other pathological lesions. The successful eruption of the tooth into oral cavity will help the child for better function and occlusion. [ABSTRACT FROM AUTHOR]