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We report simultaneous crystal growth and deposition of upconverting Yb3+/Er3+ doped NaYF4 film (UCF) on conducting and non-conducting substrates by one-step hydrothermal method. The characteristics such as film topography, morphology, crystallographic phase and upconverting luminescence intensity were found to depend both on the chelating agent and nature of the substrate. The characteristics of the prepared films varied interestingly when either the chelating agent or the substrate was changed. The upconversion emission intensities were found to increase with decreasing film roughness. Further, current investigation demonstrated that the NaYF4 films deposited using EDTA or DTPA chelating agents on ITO substrate and EGTA chelating agent on PG substrate were more uniform and resulted in greater upconverted emission intensities. We envision plausible use of current technology in the development of affordable optical platforms for several optoelectronic applications.

Background: This was a community-based, observational, cross-sectional study to determine the immunization status of children living in slums in the 26 blocks of Sangam Vihar and 4 blocks of Tigri extension area of South Delhi, India. Study Population: A total of 210 children between 12 and 23 months old. Sampling Technique: 30 cluster technique approved by the World Health Organization. Primary Outcome Measures: Immunization coverage by sex, religion, type of family, occupational status of the head of the family, stated average monthly family income, and education status of the mothers. Data collection procedure: Interview technique; principal investigator Dr. Imteyaz Ahmad collected the data using a standardized structured interview schedule with the mother/caregivers of children 12 to 23 months old after permission to conduct the study was taken from the civic authority of the local government. Record analysis of antenatal care for tetanus immunization by antenatal cards and BCG scar survey by observation of scar arm in the deltoid region for scar was also done by him. Results: One hundred and six (50.4%) children in our sample were found to be fully immunized, 88(41.9%) partially immunized and 16 (7.6%) were not immunized. Amongst these associations the difference of coverage by occupation groups and mothers education were found to be statistically significant. Conclusion: There was a discernable bias in favour of male children, Hindu children, children of nuclear family, children of non manual labour occupation parents, children from higher income family and children with mothers having high school or higher level education.