2,406 research outputs found

    The Connection Between Professional Development and Teacher Growth

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    Teachers spend hours each year attending professional development designed to further their professional growth and ultimately provide richer learning opportunities for their students. But how effective is that professional development? This dissertation explored teachers’ motivation for continuing their professional growth while determining what type of professional development teachers found inspiring. It also probed how often professional development learning was carried over into the classroom. The research was completed at a small high school in northern Colorado. Of the 53 non-probationary teachers surveyed to begin the research, three teachers were chosen for interviews. Two focus groups were conducted that consisted of three teachers, also chosen from the survey, in each group. Teachers representing various years of experience provided a broad scope of information by which to identify generalities applicable to secondary teachers. The study indicated the majority of teachers at this high school were intrinsically motivated to continue their professional growth; while monetary gain was important, it was not the main motivating factor for teachers. Professional development comprised of content or personal learning connections and chosen by the teacher was determined to be effective. Teachers preferred to have choice in professional development rather than only attending traditional professional development of the one-size-fits-all chosen by the school district or building. It was further determined teachers occasionally utilized professional development learnings in the classroom that were counterproductive to the reason for professional development. The personnel in school districts or at the building level designing professional development opportunities for their staff would benefit from providing teachers choice in their professional learning and providing support for teachers’ new learning, thereby enhancing classroom instruction for students

    Geostatistical analysis of an experimental stratigraphy

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    [1] A high-resolution stratigraphic image of a flume-generated deposit was scaled up to sedimentary basin dimensions where a natural log hydraulic conductivity (ln( K)) was assigned to each pixel on the basis of gray scale and conductivity end-members. The synthetic ln( K) map has mean, variance, and frequency distributions that are comparable to a natural alluvial fan deposit. A geostatistical analysis was conducted on selected regions of this map containing fluvial, fluvial/ floodplain, shoreline, turbidite, and deepwater sedimentary facies. Experimental ln(K) variograms were computed along the major and minor statistical axes and horizontal and vertical coordinate axes. Exponential and power law variogram models were fit to obtain an integral scale and Hausdorff measure, respectively. We conclude that the shape of the experimental variogram depends on the problem size in relation to the size of the local-scale heterogeneity. At a given problem scale, multilevel correlation structure is a result of constructing variogram with data pairs of mixed facies types. In multiscale sedimentary systems, stationary correlation structure may occur at separate scales, each corresponding to a particular hierarchy; the integral scale fitted thus becomes dependent on the problem size. The Hausdorff measure obtained has a range comparable to natural geological deposits. It increases from nonstratified to stratified deposits with an approximate cutoff of 0.15. It also increases as the number of facies incorporated in a problem increases. This implies that fractal characteristic of sedimentary rocks is both depositional process - dependent and problem-scale-dependent

    Flight investigation of a vertical-velocity command system for VTOL aircraft

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    A flight investigation was undertaken to assess the potential benefits afforded by a vertical-velocity command system (VVCS) for VTOL (vertical take-off and landing) aircraft. This augmentation system was conceived primarily as a means of lowering pilot workload during decelerating approaches to a hover and/or landing under category III instrument meteorological conditions. The scope of the investigation included a determination of acceptable system parameters, a visual flight evaluation, and an instrument flight evaluation which employed a 10 deg, decelerating, simulated instrument approach task. The results indicated that the VVCS, which decouples the pitch and vertical degrees of freedom, provides more accurate glide-path tracking and a lower pilot workload than does the unaugmented system

    Effects of butyltin exposures on MAP kinase-dependent transcription regulators in human natural killer cells

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    Natural killer (NK) cells are a major immune defense mechanism against cancer development and viral infection. The butyltins (BTs), tributyltin (TBT) and dibutyltin (DBT), have been widely used in industrial and other applications and significantly contaminate the environment. Both TBT and DBT have been detected in human blood. These compounds inhibit the lytic and binding function of human NK cells and thus could increase the incidence of cancer and viral infections. Butyltin (BT)-induced loss of NK function is accompanied by activation of mitogen activated protein kinases (MAPKs) and decreases in expression of cell-surface and cytolytic proteins. MAPKs activate components of the transcription regulator AP-1 and activate the transcription regulator Elk-1. Based on the fact that BTs activate MAPKs and alter protein expression, the current study examined the effect of BT exposures on the levels and phosphorylation states of the components of AP-1 and the phosphorylation state of Elk-1. Exposure to 300 nM TBT for 10 min increased the phosphorylation of c-Jun in NK cells. One hour exposures to 300 nM and 200 nM TBT increased the phosphorylation and overall level of c-Jun. During a 300 nM treatment with TBT for 1 h the binding activity of AP-1 was significantly decreased. There were no significant alterations of AP-1 components or of Elk-1 with DBT exposures. Thus, it appears that TBT-induced alterations on phosphorylation, total levels, and binding activity of c-Jun might contribute to, but are not fully responsible for, TBT-induced alterations of NK protein expression

    Bonding machine for forming a solar array strip

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    A machine is described for attaching solar cells to a flexable substrate on which printed circuitry has been deposited. The strip is fed through: (1) a station in which solar cells are elevated into engagement with solder pads for the printed circuitry and thereafter heated by an infrared lamp; (2) a station at which flux and solder residue is removed; (3) a station at which electrical performance of the soldered cells is determined; (4) a station at which an encapsulating resin is deposited on the cells; (5) a station at which the encapsulated solar cells are examined for electrical performance; and (6) a final station at which the resulting array is wound on a takeup drum

    Sistema de prevenção e combate a incêndios florestais no município de Campinas-SP.

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    A atividade agropecuária foi a grande responsável pela erradicação da cobertura florestal do Estado de São Paulo. Atualmente, uma das maiores ameaças aos remanescentes florestais é o risco de incêndios. Em Campinas-SP, a evolução do uso das terras acompanhou esta dinâmica. Hoje, esses remanescentes recobrem 2233 ha do Município, representando 2,8% da sua área total, distribuídos em 114 florestas que variam de 1 a 230 ha. Nos últimos 20 anos, a cobertura florestal se manteve estabilizada. São raríssimos os casos atuais de desmatamento, devido ao interesse dos proprietários em preservar essas áreas. Todavia, essas manchas isoladas de matas mesófilas não estão isentas à ocorrência de incêndios. eles destroem a vegetação, determinam uma nova fitodinâmica e levam, em geral, a uma regressão do potencial biológico dessas unidades, incluindo os povoamentos faunísticos. Entre as causas mais frequentes de incêndios estão as queimadas agrícolas em áreas vizinhas, a ação de piromaníacos, o comportamento irresponsável de transeuntes e a realização de cultos religiosos. Este trabalho inventariou todos os remanescentes florestais de Campinas-SP e elaborou um sistema de prevenção e combate a incêndios. Os resultados também estão disponíveis na Internet

    Buoyancy waves in Pluto's high atmosphere: Implications for stellar occultations

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    We apply scintillation theory to stellar signal fluctuations in the high-resolution, high signal/noise, dual-wavelength data from the MMT observation of the 2007 March 18 occultation of P445.3 by Pluto. A well-defined high wavenumber cutoff in the fluctuations is consistent with viscous-thermal dissipation of buoyancy waves (internal gravity waves) in Pluto's high atmosphere, and provides strong evidence that the underlying density fluctuations are governed by the gravity-wave dispersion relation.Comment: Accepted 18 June 2009 for publication in Icaru

    Charon's radius and density from the combined data sets of the 2005 July 11 occultation

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    The 2005 July 11 C313.2 stellar occultation by Charon was observed by three separate research groups, including our own, at observatories throughout South America. Here, the published timings from the three data sets have been combined to more accurately determine the mean radius of Charon: 606.0 +/- 1.5 km. Our analysis indicates that a slight oblateness in the body (0.006 +/- 0.003) best matches the data, with a confidence level of 86%. The oblateness has a pole position angle of 71.4 deg +/- 10.4 deg and is consistent with Charon's pole position angle of 67 deg. Charon's mean radius corresponds to a bulk density of 1.63 +/- 0.07 g/cm3, which is significantly less than Pluto's (1.92 +/- 0.12 g/cm3). This density differential favors an impact formation scenario for the system in which at least one of the impactors was differentiated. Finally, unexplained differences between chord timings measured at Cerro Pachon and the rest of the data set could be indicative of a depression as deep as 7 km on Charon's limb.Comment: 25 pages including 4 tables and 2 figures. Submitted to the Astronomical Journal on 2006 Feb 0
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