851 resultados para Full-time Schools
Resumo:
This paper examines the relationship between house price levels, school performance, and the racial and ethnic composition of Connecticut school districts between 1995 and 2000. A panel of Connecticut school districts over both time and labor market areas is used to estimate a simultaneous equations model describing the determinants of these variables. Specifically, school district changes in price level, school performance, and racial and ethnic compositions depend upon each other, labor market wide changes in these variables, and the deviation of each school district from the overall metropolitan area. The specification is based on the differencing of dependent variables, as opposed to the use of level or fixed effects models and lagging level variables beyond the period over which change is considered; as a result the model is robust to persistence in the sample. Identification of the simultaneous system arises from the presence of multiple labor market areas in the sample, and the assumption that labor market changes in a variable due not directly influence the allocation of households across towns within a labor market area. We find that towns in labor markets that experience an inflow of minority households have greater increases in percent minority if those towns already ahve a substantial minoritypopulation. We find evidence that this sorting proces is reflected in housing price changes in the low priced segment of the housing market, not in the middle and upper segments.
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Purpose. No Child Left Behind aimed to "improve the academic achievement of the disadvantaged." The primary research question considered how academic achievement of those from economic disadvantage compared to those not from disadvantage? ^ Economically disadvantaged students can potentially have added academic disadvantage. Research shows low academic achievement can potentially result in drug abuse, youth violence, and teen pregnancy. ^ Methods. To compare the student populations, measures included TAKS results and academic indicator data collected by the Texas Education Agency. ^ Results. T-test analyses showed a significant difference between the economically and non-economically disadvantaged student populations in meeting the TAKS passing standard, graduation, and preparation for higher education.^ Conclusions. The achievement gap between students remained as indicated by the Texas testing program. More research and time are needed to observe if the desired impact on those from economic disadvantage will be reflected by academic achievement data.^
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Public Health and medicine are complimentary disciplines dedicated to the health and well-being of humankind. Worldwide, medical school accreditation bodies require the inclusion of population health in medical education. In 2003, the Institutes of Medicine (IOM) recommended that all medical students receive basic public health training in population-based prevention. The purpose of this study was to (1) examine the public health clinical performance of third-year medical students at two independent medical schools, (2) compare the public health clinical practice performance of the schools, and (3) identify underlying predictors of high and low public health clinical performance at one of the medical schools. ^ This study is unique in its analysis and report of observed medical student public health clinical practices. The cohort consisted of 751 third-year medical students who completed a required clinical performance exam using trained standardized patients. Medical student performance scores on 24 consensus public health items derived from nine patient cases were analyzed.^ The analysis showed nearly identical results for both medical schools at the 60%, 65%, and 70% pass rate. Students performed poorly on items associated with prevention, behavioral science, and surveillance. Factors associated with high student performance included being from an underrepresented minority, matching to a primary care residency, and high class ranking. A review of medical school curriculum at both schools revealed a lack of training in four public health domains. Nationally, 32% of medical students reported inadequate training in public health in the year 2006.^ These findings suggest more dedicated teaching time for public health domains is needed at the medical schools represented in this study. Finally, more research is needed to assess attainment of public health knowledge and skills for medical students nationwide if we are to meet the recommendations of the IOM. ^
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Background. Infant colic is a common condition that is thought to put infants at risk for Shaken Baby Syndrome, a particularly devastating form of child abuse. However, little research has been done on techniques parents can use to deal with infant colic. This pilot study was conducted to assess the equipment that will be used in a randomized control trial that will compare the results for two different techniques that parents can use to reduce crying in infants with colic. ^ Methods. A total of 11 healthy infants, between one and five months of age, were recruited into this pilot study. All infants had a dosimeter, actiwatch and maternal log placed into the home and a subset of infants (N=3) were also recorded by a video camera. The equipment recorded between 6pm and 6am for at least two and up to five nights. The maternal log and video log were compared with one another to determine if the maternal log provides an accurate representation of the infant's night-time activities (i.e. sleep, awake, crying, feeding). The maternal log was then compared to the dosimeter and actiwatch data to determine if the dosimeter/actiwatch accurately reproduce the maternal log. ^ Results. Data from 10 infants were included in the analyses. The maternal log and video log were in full or partial agreement 90% of the time. When comparing events noted by the mother, the maternal log and dosimeter data were in agreement 84% of the time, and the maternal log and actiwatch data were in agreement 87% of the time. In combination, the dosimeter and/or actiwatch data agreed with the maternal log 90% of the time. ^ Conclusions. Our preliminary analyses of these data suggest the dosimeter and actiwatch will be useful tool for defining infant sleep patterns relative to the maternal log. However further analysis will be required to develop threshold values that can be used to objectively define events in the proposed RCT. Such analyses will need to integrate data from multiple dosimeters and deal with the shifting baselines observed for both the dosimeter and actiwatch.^
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Prevalent sampling is an efficient and focused approach to the study of the natural history of disease. Right-censored time-to-event data observed from prospective prevalent cohort studies are often subject to left-truncated sampling. Left-truncated samples are not randomly selected from the population of interest and have a selection bias. Extensive studies have focused on estimating the unbiased distribution given left-truncated samples. However, in many applications, the exact date of disease onset was not observed. For example, in an HIV infection study, the exact HIV infection time is not observable. However, it is known that the HIV infection date occurred between two observable dates. Meeting these challenges motivated our study. We propose parametric models to estimate the unbiased distribution of left-truncated, right-censored time-to-event data with uncertain onset times. We first consider data from a length-biased sampling, a specific case in left-truncated samplings. Then we extend the proposed method to general left-truncated sampling. With a parametric model, we construct the full likelihood, given a biased sample with unobservable onset of disease. The parameters are estimated through the maximization of the constructed likelihood by adjusting the selection bias and unobservable exact onset. Simulations are conducted to evaluate the finite sample performance of the proposed methods. We apply the proposed method to an HIV infection study, estimating the unbiased survival function and covariance coefficients. ^
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A monitoring programme for microzooplankton was started at the long-term sampling station ''Kabeltonne'' at Helgoland Roads (54°11.30' N; 7°54.00' E) in January 2007 in order to provide more detailed knowledge on microzooplankton occurrence, composition and seasonality patterns at this site and to complement the existing plankton data series. Ciliate and dinoflagellate cell concentration and carbon biomass were recorded on a weekly basis. Heterotrophic dinoflagellates were considerably more important in terms of biomass than ciliates, especially during the summer months. However, in early spring, ciliates were the major group of microzooplankton grazers as they responded more quickly to phytoplankton food availability. Mixotrophic dinoflagellates played a secondary role in terms of biomass when compared to heterotrophic species; nevertheless, they made up an intense late summer bloom in 2007. The photosynthetic ciliate Myrionecta rubra bloomed at the end of the sampling period. Due to its high biomass when compared to crustacean plankton especially during the spring bloom, microzooplankton should be regarded as the more important phytoplankton grazer group at Helgoland Roads. Based on these results, analyses of biotic and abiotic factors driving microzooplankton composition and abundance are necessary for a full understanding of this important component of the plankton.
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Arctic permafrost landscapes are among the most vulnerable and dynamic landscapes globally, but due to their extent and remoteness most of the landscape changes remain unnoticed. In order to detect disturbances in these areas we developed an automated processing chain for the calculation and analysis of robust trends of key land surface indicators based on the full record of available Landsat TM, ETM +, and OLI data. The methodology was applied to the ~ 29,000 km**2 Lena Delta in Northeast Siberia, where robust trend parameters (slope, confidence intervals of the slope, and intercept) were calculated for Tasseled Cap Greenness, Wetness and Brightness, NDVI, and NDWI, and NDMI based on 204 Landsat scenes for the observation period between 1999 and 2014. The resulting datasets revealed regional greening trends within the Lena Delta with several localized hot-spots of change, particularly in the vicinity of the main river channels. With a 30-m spatial resolution various permafrost-thaw related processes and disturbances, such as thermokarst lake expansion and drainage, fluvial erosion, and coastal changes were detected within the Lena Delta region, many of which have not been noticed or described before. Such hotspots of permafrost change exhibit significantly different trend parameters compared to non-disturbed areas. The processed dataset, which is made freely available through the data archive PANGAEA, will be a useful resource for further process specific analysis by researchers and land managers. With the high level of automation and the use of the freely available Landsat archive data, the workflow is scalable and transferrable to other regions, which should enable the comparison of land surface changes in different permafrost affected regions and help to understand and quantify permafrost landscape dynamics.
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DATED-1 comprises a compilation of dates related to the build-up and retreat of the Eurasian (British-Irish, Scandinavian, Svalbard-Barents-Kara Seas) Ice Sheets, and time-slice maps of the Eurasian Ice sheet margins. Dates are sourced from the published literature. Ice margins are based on published geological and chronological data and include uncertainty bounds (maximum, minimum) as well as what we consider to be the most-credible (mc) based on the available evidence. DATED-1 has a census date of 1 January 2013. Full description and caveats for use are given in: Hughes, A.L.C., Gyllencreutz, R., Lohne, Ø.S., Mangerud, J., Svendsen, J.I. (2015) The last Eurasian Ice Sheets - a chronological database and time-slice reconstruction, DATED-1.