56 research outputs found
Determining and Measuring Self-Efficacy During the Student Teaching Semester
Self-efficacy is the belief that an individual is able to control the outcomes of potentially stressful situations. How teacher candidates feel about their ability to control new challenges can affect their performance in the classroom. Those with a poorer sense of self-efficacy may believe situations are out of their control. A more positive sense of perceived self-efficacy can lead to more positive outcomes. This article reports the results of a teacher self-efficacy scale administered to elementary and secondary teacher candidates at the beginning and end of their student teaching semester. Findings suggest that perceived self-efficacy among student teachers increases throughout the course of the student teaching experience
Bad Practice in Erosion Management: The Southern Sicily Case Study
This case study from Sicily illustrates a common sequence of events
where one unwise action was countered with another, which in turn created
additional problems. The situation arose through strong political interference and
ignorance (or lack of concern) regarding the environmental impacts of human
interventions on the shoreline and by the public perception that government has a
duty to protect private property. The poor design and location of ports and harbours
produced infilling problems and huge updrift accretion with concomitant downdrift
erosion. The human-induced coastal retreat was counteracted by the progressive
emplacement of breakwaters creating a “domino” effect. On many occasions
these were constructed to protect unplanned and illegal (in the sense that they do
not conform to planning regulations) beachfront summer houses. Without the
presence of these structures, there would have been no need for publicly funded
intervention.
Furthermore, only a narrow coastal belt close to the shoreline is used by
bathers on the wide beaches formed updrift of ports and harbours and in the lee
of breakwaters, most of the accreted beach being unused or partially occupied by
tourist developments. Thus beach users and municipalities acquired some benefits
from beach accretion at specific sites, the opposite being true in eroding areas
The Thermal Design, Characterization, and Performance of the SPIDER Long-Duration Balloon Cryostat
We describe the SPIDER flight cryostat, which is designed to cool six
millimeter-wavelength telescopes during an Antarctic long-duration balloon
flight. The cryostat, one of the largest to have flown on a stratospheric
payload, uses liquid helium-4 to deliver cooling power to stages at 4.2 and 1.6
K. Stainless steel capillaries facilitate a high flow impedance connection
between the main liquid helium tank and a smaller superfluid tank, allowing the
latter to operate at 1.6 K as long as there is liquid in the 4.2 K main tank.
Each telescope houses a closed cycle helium-3 adsorption refrigerator that
further cools the focal planes down to 300 mK. Liquid helium vapor from the
main tank is routed through heat exchangers that cool radiation shields,
providing negative thermal feedback. The system performed successfully during a
17 day flight in the 2014-2015 Antarctic summer. The cryostat had a total hold
time of 16.8 days, with 15.9 days occurring during flight.Comment: 15 pgs, 17 fig
Double Dissociation of Amygdala and Hippocampal Contributions to Trace and Delay Fear Conditioning
A key finding in studies of the neurobiology of learning memory is that the amygdala is critically involved in Pavlovian fear conditioning. This is well established in delay-cued and contextual fear conditioning; however, surprisingly little is known of the role of the amygdala in trace conditioning. Trace fear conditioning, in which the CS and US are separated in time by a trace interval, requires the hippocampus and prefrontal cortex. It is possible that recruitment of cortical structures by trace conditioning alters the role of the amygdala compared to delay fear conditioning, where the CS and US overlap. To investigate this, we inactivated the amygdala of male C57BL/6 mice with GABA A agonist muscimol prior to 2-pairing trace or delay fear conditioning. Amygdala inactivation produced deficits in contextual and delay conditioning, but had no effect on trace conditioning. As controls, we demonstrate that dorsal hippocampal inactivation produced deficits in trace and contextual, but not delay fear conditioning. Further, pre- and post-training amygdala inactivation disrupted the contextual but the not cued component of trace conditioning, as did muscimol infusion prior to 1- or 4-pairing trace conditioning. These findings demonstrate that insertion of a temporal gap between the CS and US can generate amygdala-independent fear conditioning. We discuss the implications of this surprising finding for current models of the neural circuitry involved in fear conditioning
Is early detection of abused children possible?: a systematic review of the diagnostic accuracy of the identification of abused children
Particle response of antenna-coupled TES arrays: results from SPIDER and the laboratory
Future mm-wave and sub-mm space missions will employ large arrays of multiplexed transition-edge-sensor (TES) bolometers. Such instruments must contend with the high flux of cosmic rays beyond our atmosphere that induce ‘glitches’ in bolometer data, which posed a challenge to data analysis from the Planck bolometers. Future instruments will face the additional challenges of shared substrate wafers and multiplexed readout wiring. In this work, we explore the susceptibility of modern TES arrays to the cosmic ray environment of space using two data sets: the 2015 long-duration balloon flight of the SPIDER cosmic microwave background polarimeter, and a laboratory exposure of SPIDER flight hardware to radioactive sources. We find manageable glitch rates and short glitch durations, leading to minimal effect on SPIDER analysis. We constrain energy propagation within the substrate through a study of multi-detector coincidences and give a preliminary look at pulse shapes in laboratory data
A New Limit on CMB Circular Polarization from SPIDER
We present a new upper limit on cosmic microwave background (CMB) circular polarization from the 2015 flight of Spider, a balloon-borne telescope designed to search for B-mode linear polarization from cosmic inflation. Although the level of circular polarization in the CMB is predicted to be very small, experimental limits provide a valuable test of the underlying models. By exploiting the nonzero circular-to-linear polarization coupling of the half-wave plate polarization modulators, data from Spider's 2015 Antarctic flight provide a constraint on Stokes V at 95 and 150 GHz in the range . No other limits exist over this full range of angular scales, and Spider improves on the previous limit by several orders of magnitude, providing 95% C.L. constraints on ranging from 141 to 255 μK2 at 150 GHz for a thermal CMB spectrum. As linear CMB polarization experiments become increasingly sensitive, the techniques described in this paper can be applied to obtain even stronger constraints on circular polarization
The Arcminute Cosmology Bolometer Array Receiver (ACBAR).
We describe the Arcminute Cosmology Bolometer Array Receiver (ACBAR) which is a 16 pixel, 240mK multifrequency bolometer array for measuring primary and secondary anisotropies in the CMB at millimeter wavelengths. ACBAR observes from the 2m Viper telescope at the South Pole and has just concluded its second year of CMB mapping observations. In this talk we will discuss the instrument design and performance as well as preliminary results from a blind survey for massive clusters of galaxies using the SZ effect. ACBAR is funded by the Center for Astrophysical Research in Antarctica (CARA), an NSF Science and Technology Center
Anterior cruciate ligament reconstruction: Magnetic resonance imaging and factors influencing outcome
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