609 research outputs found

    Relationship Between Student Academic Achievement and Gender of Campus Administrator

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    Studies of the effectiveness of women’s leadership have been recommended by researchers for over three decades (e.g. Eckman, 2004; Edson, 1988; Schmuck, 1981; Shakeshaft, 1989). Burke & Nelson (2002) and Smulyan (2000) have suggested that a woman’s leadership experience is fundamentally influenced by gender. As greater numbers of women fill educational administration positions previously held by men (Addi-Raccah, 2006; Rusch & Marshall, 2006), opportunities to study leadership differences and effectiveness of men and women in meeting unique demands of their campuses can be measured. Although issues related to women leaders in superintendent positions have been explored (Tallerico, 1999; Brunner, 1999; Blount, 1998; Grogan, 1996), few studies have investigated women’s leadership at the campus level (Goldberg, 1991; Ortiz 1982; Shakeshaft, 1989; Schneider, 1986). Furthermore, identification of the complex leadership attributes of women might clarify the dynamics of their advancement into campus administration (Burke &Nelson, 2002)

    Rural Principal Leadership Skill Proficiency And Student Achievement

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    Warren and Peel (2005) found that rural schools can effectively develop focused leadership support and training. However, as indicated by Arnold, et al. (2004), the knowledge and skills most critical to effective rural administration have yet to be identified. Targeting specific leadership skills related to student achievement might focus university principal preparation programs and public school district staff development programs on producing more effective rural leadership. Ultimately, this emphasis may improve student achievement and school performance in rural schools. Because of the importance of developing highly skilled rural school leaders, this study will endeavor to identify the leadership skills of practicing rural administrators and determine whether these skills were related to campus student achievement

    TESS delivers its first Earth-sized planet and a warm sub-Neptune

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    The future of exoplanet science is bright, as TESS once again demonstrates with the discovery of its longest-period confirmed planet to date. We hereby present HD 21749b (TOI 186.01), a sub-Neptune in a 36-day orbit around a bright (V = 8.1) nearby (16 pc) K4.5 dwarf. TESS measures HD21749b to be 2.61−0.16+0.17^{+0.17}_{-0.16} R⊕R_{\oplus}, and combined archival and follow-up precision radial velocity data put the mass of the planet at 22.7−1.9+2.222.7^{+2.2}_{-1.9} M⊕M_{\oplus}. HD 21749b contributes to the TESS Level 1 Science Requirement of providing 50 transiting planets smaller than 4 R⊕R_{\oplus} with measured masses. Furthermore, we report the discovery of HD 21749c (TOI 186.02), the first Earth-sized (Rp=0.892−0.058+0.064R⊕R_p = 0.892^{+0.064}_{-0.058} R_{\oplus}) planet from TESS. The HD21749 system is a prime target for comparative studies of planetary composition and architecture in multi-planet systems.Comment: Published in ApJ Letters; 5 figures, 1 tabl

    A sub-Neptune transiting the young field star HD 18599  at 40 pc

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    Transiting exoplanets orbiting young nearby stars are ideal laboratories for testing theories of planet formation and evolution. However, to date only a handful of stars with age <1 Gyr have been found to host transiting exoplanets. Here we present the discovery and validation of a sub-Neptune around HD 18599 , a young (300 Myr), nearby (d = 40 pc) K star. We validate the transiting planet candidate as a bona fide planet using data from the TESS , Spitzer , and Gaia  missions, ground-based photometry from IRSF , LCO , PEST , and NGTS , speckle imaging from Gemini, and spectroscopy from CHIRON , NRES , FEROS , and Minerva-Australis . The planet has an orbital period of 4.13 d , and a radius of 2.7 R⊕ . The RV data yields a 3-σ mass upper limit of 30.5 M⊕  which is explained by either a massive companion or the large observed jitter typical for a young star. The brightness of the host star (V∌9 mag) makes it conducive to detailed characterization via Doppler mass measurement which will provide a rare view into the interior structure of young planets

    Design, Performance, and Calibration of CMS Hadron-Barrel Calorimeter Wedges

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    Extensive measurements have been made with pions, electrons and muons on four production wedges of the Compact Muon Solenoid (CMS) hadron barrel (HB) calorimeter in the H2 beam line at CERN with particle momenta varying from 20 to 300 GeV/c. Data were taken both with and without a prototype electromagnetic lead tungstate crystal calorimeter (EB) in front of the hadron calorimeter. The time structure of the events was measured with the full chain of preproduction front-end electronics running at 34 MHz. Moving-wire radioactive source data were also collected for all scintillator layers in the HB. These measurements set the absolute calibration of the HB prior to first pp collisions to approximately 4%

    Synchronization and Timing in CMS HCAL

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    The synchronization and timing of the hadron calorimeter (HCAL) for the Compact Muon Solenoid has been extensively studied with test beams at CERN during the period 2003-4, including runs with 40 MHz structured beam. The relative phases of the signals from different calorimeter segments are timed to 1 ns accuracy using a laser and equalized using programmable delay settings in the front-end electronics. The beam was used to verify the timing and to map out the entire range of pulse shapes over the 25 ns interval between beam crossings. These data were used to make detailed measurements of energy-dependent time slewing effects and to tune the electronics for optimal performance

    Energy Response and Longitudinal Shower Profiles Measured in CMS HCAL and Comparison With Geant4

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    The response of the CMS combined electromagnetic and hadron calorimeter to beams of pions with momenta in the range 5-300 GeV/c has been measured in the H2 test beam at CERN. The raw response with the electromagnetic compartment calibrated to electrons and the hadron compartment calibrated to 300 GeV pions may be represented by sigma = (1.2) sqrt{E} oplus (0.095) E. The fraction of energy visible in the calorimeter ranges from 0.72 at 5 GeV to 0.95 at 300 GeV, indicating a substantial nonlinearity. The intrinsic electron to hadron ratios are fit as a function of energy and found to be in the range 1.3-2.7 for the electromagnetic compartment and 1.4-1.8 for the hadronic compartment. The fits are used to correct the non-linearity of the e pi response to 5% over the entire measured range resulting in a substantially improved resolution at low energy. Longitudinal shower profile have been measured in detail and compared to Geant4 models, LHEP-3.7 and QGSP-2.8. At energies below 30 GeV, the data, LHEP and QGSP are in agreement. Above 30 GeV, LHEP gives a more accurate simulation of the longitudinal shower profile

    Design, Performance, and Calibration of CMS Hadron Endcap Calorimeters

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    Detailed measurements have been made with the CMS hadron calorimeter endcaps (HE) in response to beams of muons, electrons, and pions. Readout of HE with custom electronics and hybrid photodiodes (HPDs) shows no change of performance compared to readout with commercial electronics and photomultipliers. When combined with lead-tungstenate crystals, an energy resolution of 8\% is achieved with 300 GeV/c pions. A laser calibration system is used to set the timing and monitor operation of the complete electronics chain. Data taken with radioactive sources in comparison with test beam pions provides an absolute initial calibration of HE to approximately 4\% to 5\%

    Design, Performance, and Calibration of the CMS Hadron-Outer Calorimeter

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    The CMS hadron calorimeter is a sampling calorimeter with brass absorber and plastic scintillator tiles with wavelength shifting fibres for carrying the light to the readout device. The barrel hadron calorimeter is complemented with an outer calorimeter to ensure high energy shower containment in the calorimeter. Fabrication, testing and calibration of the outer hadron calorimeter are carried out keeping in mind its importance in the energy measurement of jets in view of linearity and resolution. It will provide a net improvement in missing \et measurements at LHC energies. The outer hadron calorimeter will also be used for the muon trigger in coincidence with other muon chambers in CMS

    Multiple sclerosis genomic map implicates peripheral immune cells and microglia in susceptibility

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