915 research outputs found

    Tetanus and diphtheria immunity in adolescents from São Paulo, Brazil

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    Tetanus and diphtheria vaccines are of special concern in adolescents because boosters are necessary for adequate maintenance of protection and are often omitted. We assessed serum levels of tetanus and diphtheria antibodies in adolescents and their association with vaccination status. From May to October 2001, we evaluated the vaccination records of 208 adolescents aged 10 to 20 years in São Paulo, Brazil. Antibodies to tetanus and diphtheria were detected using double-antigen ELISA and vaccination records were analyzed according to the guidelines of the Brazilian National Immunization Program. All adolescents had received complete primary vaccinations against tetanus and diphtheria, but 23.1% of them had not received a booster dose in the last 10 years. All adolescents were immune to tetanus and 88.9% were fully protected (antibodies ³0.1 IU/mL). One individual (0.5%) was non-immune to diphtheria and 86% were fully protected against the disease. Adolescents with up-to-date vaccination records had higher antibody levels than those with not up-to-date records for tetanus (0.763 vs 0.239 IU/mL, t-test: P < 0.0001) and diphtheria (0.366 vs 0.233 IU/mL, t-test: P = 0.014). Full immunity against tetanus (antibodies ³0.1 IU/mL) was higher among individuals with up-to-date vaccination (93.1%) when compared to those with not up-to-date records (75%, Fisher's exact test: P = 0.001). All adolescents had received basic immunization in childhood and were protected against tetanus and diphtheria. However, these data indicate that more emphasis should be placed on the tetanus-diphtheria booster in order to avoid a decay in antibody levels

    Using \u3cem\u3eClicker\u3c/em\u3e 5 to Enhance Emergent Literacy in Young Learners

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    Best practices in emergent literacy instruction for young children acknowledge and facilitate the smooth progression between children’s early engagement with print materials and subsequent fuller literacy mastery. In so doing, model programs target five key emergent literacy skills. The rapid rise in the breadth and depth of educational technology, including computer software, is offering early childhood education professionals new and powerful tools in teaching early literacy. This paper offers a brief review of best practices in emergent literacy, notes the growth of technology in this instruction, and examines the potential contributions of one specific software program, Clicker 5, in helping diverse emergent literacy learners acquire and practice initial reading and writing skills

    Extreme ozone depletion in the 2010–2011 Arctic winter stratosphere as observed by MIPAS/ENVISAT using a 2-D tomographic approach

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    Abstract. We present observations of the 2010–2011 Arctic winter stratosphere from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) onboard ENVISAT. Limb sounding infrared measurements were taken by MIPAS during the Northern polar winter and into the subsequent spring, giving a continuous vertically resolved view of the Arctic dynamics, chemistry and polar stratospheric clouds (PSCs). We adopted a 2-D tomographic retrieval approach to account for the strong horizontal inhomogeneity of the atmosphere present under vortex conditions, self-consistently comparing 2011 to the 2-D analysis of 2003–2010. Unlike most Arctic winters, 2011 was characterized by a strong stratospheric vortex lasting until early April. Lower stratospheric temperatures persistently remained below the threshold for PSC formation, extending the PSC season up to mid-March, resulting in significant chlorine activation leading to ozone destruction. On 3 January 2011, PSCs were detected up to 30.5 ± 0.9 km altitude, representing the highest PSCs ever reported in the Arctic. Through inspection of MIPAS spectra, 83% of PSCs were identified as supercooled ternary solution (STS) or STS mixed with nitric acid trihydrate (NAT), 17% formed mostly by NAT particles, and only two cases by ice. In the lower stratosphere at potential temperature 450 K, vortex average ozone showed a daily depletion rate reaching 100 ppbv day−1. In early April at 18 km altitude, 10% of vortex measurements displayed total depletion of ozone, and vortex average values dropped to 0.6 ppmv. This corresponds to a chemical loss from early winter greater than 80%. Ozone loss was accompanied by activation of ClO, associated depletion of its reservoir ClONO2, and significant denitrification, which further delayed the recovery of ozone in spring. Once the PSC season halted, ClO was reconverted primarily into ClONO2. Compared to MIPAS observed 2003–2010 Arctic average values, the 2010–2011 vortex in late winter had 15 K lower temperatures, 40% lower HNO3 and 50% lower ozone, reaching the largest ozone depletion ever observed in the Arctic. The overall picture of this Arctic winter was remarkably closer to conditions typically found in the Antarctic vortex than ever observed before
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