1,514 research outputs found

    Does Choice in School Selection Contribute to Ninth Grade Academic Achievement?

    Get PDF
    Ninth grade achievement is pivotal for the success of a student to graduate and avoid dropping out of school. Students are transitioned as ninth graders into schools not of their choosing or assigned to neighborhood schools. While there is extensive research on ninth grade achievement, dropout risk factors and student motivation, there is a gap in the literature in how school selection plays a role in ninth grade academic achievement. The purpose of this study was to explore how choice, in the selection of schools, contributed to ninth grade academic achievement. This study investigated the relationship of choice and ninth grade success for students who chose their high school in an urban district in the Northeast region of the United States. Students’ grade point average, attendance and credits earned were compiled in an experimental study. The ANOVA analysis compared data of those students who received their first choice school assignment against those students who received their third choice school assignment and fifth through eight choice assignment. A major finding was that ninth graders who were placed in their first choice school had better attendance than other students in the other choice groups. After a student’s choice has been made there is a need to know how student outcomes are positively impacted by this choice. A school of choice process should be viewed as a comprehensive framework process which begins at the time of choice and concludes at the end of a student’s first year in the new placement

    Seafloor Control on Sea Ice

    Get PDF
    The seafloor has a profound role in Arctic sea ice formation and seasonal evolution. Ocean bathymetry controls the distribution and mixing of warm and cold waters, which may originate from different sources, thereby dictating the pattern of sea ice on the ocean surface. Sea ice dynamics, forced by surface winds, are also guided by seafloor features in preferential directions. Here, satellite mapping of sea ice together with buoy measurements are used to reveal the bathymetric control on sea ice growth and dynamics. Bathymetric effects on sea ice formation are clearly observed in the conformation between sea ice patterns and bathymetric characteristics in the peripheral seas. Beyond local features, bathymetric control appears over extensive ice-prone regions across the Arctic Ocean. The large-scale conformation between bathymetry and patterns of different synoptic sea ice classes, including seasonal and perennial sea ice, is identified. An implication of the bathymetric influence is that the maximum extent of the total sea ice cover is relatively stable, as observed by scatterometer data in the decade of the 2000s, while the minimum ice extent has decreased drastically. Because of the geologic control, the sea ice cover can expand only as far as it reaches the seashore, the continental shelf break, or other pronounced bathymetric features in the peripheral seas. Since the seafloor does not change significantly for decades or centuries, sea ice patterns can be recurrent around certain bathymetric features, which, once identified, may help improve short-term forecast and seasonal outlook of the sea ice cover. Moreover, the seafloor can indirectly influence cloud cover by its control on sea ice distribution, which differentially modulates the latent heat flux through ice covered and open water areas

    The Recent High State of the BL Lacertae Object AO 0235 and Cross-Correlations Between Optical and Radio Bands

    Get PDF
    We present new optical (B, V , R, I) and radio (at 14.5, 8.5, and 4.8 GHz) observations of the Îł-ray- loud blazar AO 0235+164 obtained during the high state of 1997 December-1998 January. The data were combined with historical light curves from the literature to study correlated optical and radio variations over a time span of more than 20 years. Flux variability with large and energy-dependent amplitude is observed at both wave bands, with the source varying over all timescales sampled (years-months- days), in agreement with previous reports. We have performed a cross-correlation analysis of optical and radio light curves applying various detailed statistical methods. The principal results of our analysis can be summarized as follows : (1) we find that the optical and radio variations exhibit correlated flux changes at their average level , stressing the conclusion that the same emission mechanism is responsible for the radiation in the two bands (i.e., synchrotron emission from shocked plasma in the jet). However, as previously reported, a few strong flares at optical do not have obvious counterparts at longer wavelengths, possibly indicating that an additional component is present in the optical (e.g., microlensing), or, alternatively, rapid cooling of the synchrotron particles in a radiative shock. (2) Periodic variations are observed at radio frequencies (14.5 and 8.0 GHz) with a pattern repeating every ~5.8 years, as indicated by the Lomb-Scargle periodogram. This is the first report for periodicity at radio wavelengths for this source; future continuous monitoring is needed to confirm this result. (3) Through the analysis of B-V and R-I slopes, we observe large spectral variations, with a bimodal behavior. In the first state, the emission is consistent with a variable power law all across the sampled optical region (from R to V bands); in the second state, the R-I slope is constant while the B-V slope varies, i.e., the continuum has various degrees of curvature at the shorter wavelengths. In general, the power-law slope is not correlated with the f;ux of the source. However, there is an indication that when the source is in the first state, the spectrum becomes softer as the source brightens

    Mechanism of age-dependent susceptibility and novel treatment strategy in glutaric acidemia type I

    Get PDF
    Glutaric acidemia type I (GA-I) is an inherited disorder of lysine and tryptophan metabolism presenting with striatal lesions anatomically and symptomatically similar to Huntington disease. Affected children commonly suffer acute brain injury in the context of a catabolic state associated with nonspecific illness. The mechanisms underlying injury and age-dependent susceptibility have been unknown, and lack of a diagnostic marker heralding brain injury has impeded intervention efforts. Using a mouse model of GA-I, we show that pathologic events began in the neuronal compartment while enhanced lysine accumulation in the immature brain allowed increased glutaric acid production resulting in age-dependent injury. Glutamate and GABA depletion correlated with brain glutaric acid accumulation and could be monitored in vivo by proton nuclear magnetic resonance (1H NMR) spectroscopy as a diagnostic marker. Blocking brain lysine uptake reduced glutaric acid levels and brain injury. These findings provide what we believe are new monitoring and treatment strategies that may translate for use in human GA-I

    Higgs-Boson Mass Limits and Precise Measurements beyond the Standard Model

    Full text link
    The triviality and vacuum stability bounds on the Higgs-boson mass (\mh) were revisited in presence of weakly-coupled new interactions parameterized in a model-independent way by effective operators of dimension 6. The constraints from precision tests of the Standard Model were taken into account. It was shown that for the scale of new physics in the region \Lambda \simeq 2 \div 50 \tev the Standard Model triviality upper bound remains unmodified whereas it is natural to expect that the lower bound derived from the requirement of vacuum stability is substantially modified depending on the scale \La and strength of coefficients of effective operators. A natural generalization of the standard triviality condition leads also to a substantial reduction of the allowed region in the (\Lambda,\mh) space.Comment: 18 pages 3 eps figures. The discussion in the appendix was modified slightly and some typographical errors were correcte

    Interprofessional communication with hospitalist and consultant physicians in general internal medicine : a qualitative study

    Get PDF
    This study helps to improve our understanding of the collaborative environment in GIM, comparing the communication styles and strategies of hospitalist and consultant physicians, as well as the experiences of providers working with them. The implications of this research are globally important for understanding how to create opportunities for physicians and their colleagues to meaningfully and consistently participate in interprofessional communication which has been shown to improve patient, provider, and organizational outcomes

    GJ 1252 b: A 1.2 R\u3csub\u3e⊕\u3c/sub\u3e Planet Transiting An M3 Dwarf At 20.4 pc

    Get PDF
    We report the discovery of GJ 1252 b, a planet with a radius of 1.193 ± 0.074 R⊕ and an orbital period of 0.52 days around an M3-type star (0.381 ± 0.019 M⊕, 0.391 ± 0.020 R⊕) located 20.385 ± 0.019 pc away. We use Transiting Exoplanet Survey Satellite (TESS) data, ground-based photometry and spectroscopy, Gaia astrometry, and high angular resolution imaging to show that the transit signal seen in the TESS data must originate from a transiting planet. We do so by ruling out all false-positive scenarios that attempt to explain the transit signal as originating from an eclipsing stellar binary. Precise Doppler monitoring also leads to a tentative mass measurement of 2.09 ± 0.56 M⊕. The host star proximity, brightness (V = 12.19 mag, K = 7.92 mag), low stellar activity, and the system\u27s short orbital period make this planet an attractive target for detailed characterization, including precise mass measurement, looking for other objects in the system, and planet atmosphere characterization

    Selection and integration of earth observation-based data for an operational disease forecasting system

    Get PDF
    The current increase in the volume and quality of Earth Observation (EO) data being collected by satellites offers the potential to contribute to applications across a wide range of scientific domains. It is well established that there are correlations between characteristics that can be derived from EO satellite data, such as land surface temperature or land cover, and the incidence of some diseases. Thanks to the reliable frequent acquisition and rapid distribution of EO data it is now possible for this field to progress from using EO in retrospective analyses of historical disease case counts to using it in operational forecasting systems. However, bringing together EO-based and non-EO-based datasets, as is required for disease forecasting and many other fields, requires carefully designed data selection, formatting and integration processes. Similarly, it requires careful communication between collaborators to ensure that the priorities of that design process match the requirements of the application. Here we will present work from the D-MOSS (Dengue forecasting MOdel Satellite-based System) project. D-MOSS is a dengue fever early warning system for South and South East Asia that will allow public health authorities to identify areas at high risk of disease epidemics before an outbreak occurs in order to target resources to reduce spreading of epidemics and improve disease control. The D-MOSS system uses EO, meteorological and seasonal weather forecast data, combined with disease statistics and static layers such as land cover, as the inputs into a dengue fever model and a water availability model. Water availability directly impacts dengue epidemics due to the provision of mosquito breeding sites. The datasets are regularly updated with the latest data and run through the models to produce a new monthly forecast. For this we have designed a system to reliably feed standardised data to the models. The project has involved a close collaboration between remote sensing scientists, geospatial scientists, hydrologists and disease modelling experts. We will discuss our approach to the selection of data sources, data source quality assessment, and design of a processing and ingestion system to produce analysis-ready data for input to the disease and water availability models
    • 

    corecore