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This study of early-career teachers identified a significant relationship between upper-elementary teachers' mathematical content knowledge and their students' mathematics achievement, after controlling for student- and teacher-level characteristics. Findings provide evidence of the relevance of teacher knowledge and perceptions for teacher preparation and professional development programs.

In this paper, we present the design, modeling, and measurements of feed born coupled large bolometer arrays being developed for the Herschel Space Observatory's Spectral and Photometric Imaging REceiver (SPIRE) instrument. SPIRE has five arrays of feed horn coupled silicon-nitride micromesh 'spider-web' bolometers in two instruments, a three-band photometer, and a two-band Fourier transform spectrometer, each covering the 430-GHz-1.5-THz band. The optical coupling efficiency, bandwidth, and crosstalk between adjacent pixels of the arrays were investigated with numerical electromagnetic-field simulators, and prototype arrays were measured extensively in a test facility. The measured results were found to be in good agreement with simulation predictions, and the simulation results were used as a benchmark for the design goals of the instrument. Index Terms--Feed horn coupled arrays, Fourier transform spectrometer (FTS), HFSS simulations, integrating cavities, photometer, spider-web bolometers.

Bolometers designed to detect submillimeter radiation also respond to cosmic, gamma, and x rays. Because detectors cannot be fully shielded from such energy sources, it is necessary to understand the effect of a photon or cosmic-ray particle being absorbed. The resulting signal (known as a glitch) can then be removed from raw data. We present measurements using an Americium-241 gamma radiation source to irradiate a prototype bolometer for the High Frequency Instrument in the Planck Surveyor satellite. Our measurements showed no variation in response depending on where the radiation was absorbed, demonstrating that the bolometer absorber and thermistor thermalize quickly. The bolometer has previously been fully characterized both electrically and optically. We find that using optically measured time constants underestimates the time taken for the detector to recover from a radiation absorption event. However, a full thermal model for the bolometer, with parameters taken from electrical and optical measurements, provides accurate time constants. Slight deviations from the model were seen at high energies; these can be accounted for by use of an extended model. OCIS codes: 040.0040, 040.3060, 040.7480.

Neptune was observed by the Infrared Space Observatory (ISO) Long-Wavelength Spectrometer (LWS) between 46 and 185 [micro]m. At wavelengths between 50 and 110 pm the accuracy of these measurements is [less than or equal to] 0.3 K. Observations of this planet made by the ISO Short-Wavelength Spectrometer between 28 and 44 gm were combined with the LWS data to determine a disk-averaged temperature profile and derive several physical quantities. The combined spectra are matched best by a He/([H.sub.2] + He) mass ratio of [26.4.sup.+2.6.sub.-3.5]%, reflecting a He molar fraction of [14.9.sup.+1.7.sub.-2.2]%, assuming the molar fraction of C[H.sub.4] to be 2% in the troposphere. This He abundance is consistent with one derived from analysis of joint Voyager-2 IRIS and radio occultation experiment data, a technique whose accuracy has recently been called into question. For a disk average, the para-[H.sub.2] fraction is found to be no more than ~ 1.5% different from its equilibrium value, and the [N.sub.2] mixing ratio is probably less than 0.7%. The composite spectrum is best fit by invoking a C[H.sub.4] ice condensate cloud. Using a Mie approximation to particle scattering and absorption, best-fit particle sizes lie between 15 and 40 pm. The composite spectra are relatively insensitive to the vertical distribution of the cloud, but the particle scale height must be greater than 5% of the gas scale height. The best models are consistent with an effective temperature for Neptune that is 59.5 [+ or -] 0.6 K, a value slightly lower than derived by the Voyager IRIS experiment--possibly Neptune's mid- and far-infrared emission has changed during the seven years that lie between its encounter with Voyager 2 and the first spectra taken of this planet with ISO. The model spectra are also ostensibly lower than ground-based observations in the spectral range of 17-24 [micro]m, but this discrepancy can be relieved by perturbing the temperature of the lower stratosphere where the LWS spectrum is not particularly sensitive, combined with the uncertainty in the absolute calibration of the ground-based measurements. Keywords: Infrared observations; Neptune; Abundances; Atmospheres; Spectrophotometry

Modern far-infrared and submillimeter instruments require large-format arrays. We consider the relative performance of filled-array (bare pixel) and feedhorn-coupled architectures for bolometer focal planes. Based on typical array parameters, we quantify the relative observing speeds and comment on the merits of the different architectures. Filled arrays can provide higher mapping speed (by a factor of as much as 3.5) and simpler observing modes at the expense of reduced sensitivity for pointed observations, increased detector numbers, and greater vulnerability to stray light and electromagnetic interference. Taking advantage of the filled-array architecture requires strongly background-limited detectors. At millimeter wavelengths, filled arrays must be surrounded by a sufficiently cold enclosure to minimize the background power from the instrument itself. OCIS codes: 040.0040, 040.3060, 350.0350.

Background: Acute complete Achilles tendon ruptures are commonly missed injuries. We propose the Realtime Achilles Ultrasound Thompson (RAUT) test, a Thompson test under ultrasound visualization, to aid in the diagnosis of these injuries. We hypothesized that RAUT testing would provide improved diagnostic characteristics compared with static ultrasound. Methods: Twenty-two consecutive patients with operatively confirmed acute Achilles tendon ruptures were prospectively evaluated with RAUT testing and static ultrasonography. RAUT video recordings and static ultrasound images from both ruptured and uninjured sides were randomized and graded by a group of novice reviewers and a group of expert attendings. From these observations, sensitivity, specificity, positive predictive value, and negative predictive value for RAUT and static ultrasound were calculated. In addition, κ interobserver coefficients were computed. Forty-seven novice reviewers and 11 foot and ankle attendings made a total of 4136 and 528 observations, respectively. Results: For static ultrasound, sensitivity and specificity were 76.8% and 74.8% for the novice reviewers and 79.6% and 86.4% for the attendings, respectively. For RAUT testing, sensitivity and specificity were 87.2% and 81.1% for the novice group and 86.4% and 91.7% for the attending group, respectively. The κ coefficient was 0.62 and 0.27 for novice and attending RAUT reviewers, indicating substantial and fair agreement, respectively, but only 0.46 and 0.12 for static ultrasonography, representing moderate and slight agreement, respectively. Conclusion: RAUT testing was a sensitive and specific test, providing a cost-effective adjunct to the clinical examination when diagnosing acute Achilles tendon ruptures. This test can be used by surgeons with minimal training in ultrasonography. Level of Evidence: Level II, diagnostic study. [ABSTRACT FROM AUTHOR]

We developed a novel conductometric device with nanostructured gold (Au) sensitive layer which showed high-performance for elemental mercury (Hg0) vapor detection under simulated conditions that resemble harsh industrial environments. That is, the Hg0 vapor sensing performance of the developed sensor was investigated under different operating temperatures (30-130 °C) and working conditions (i.e., humid) as well as in the presence of various interfering gas species, including ammonia (NH3), hydrogen sulfide (H2S), nitric oxide (NO), carbon mono-oxide (CO), carbon dioxide (CO2), sulfur dioxide (SO2), hydrogen (H2), methane (CH4), and volatile organic compounds (VOCs) such as ethylmercaptan (EM), acetaldehyde (MeCHO) and methyl ethyl ketone (MEK) among others. The results indicate that the introduction of Au nanostructures (referred to as nanospikes) on the sensor's surface enhanced the sensitivity toward Hg0 vapor by up-to 450%. The newly developed sensor exhibited a limit of detection (LoD) (~35 μg/m³), repeatability (~94%), desorption efficiency (100%) and selectivity (~93%) when exposed to different concentrations of Hg0 vapor (0.5 to 9.1 mg/m³) and interfering gas species at a chosen operating temperature of 105 °C. Furthermore, the sensor was also found to show 91% average selectivity when exposed toward harsher industrial gases such as NO, CO, CO2, and SO2 along with same concentrations of Hg0 vapor in similar operating conditions. In fact, this is the first time a conductometric sensor is shown to have high selectivity toward Hg0 vapor even in the presence of H2S. Overall results indicate that the developed sensor has immense potential to be used as accurate online Hg0 vapor monitoring technology within industrial processes. [ABSTRACT FROM AUTHOR]

The Lycopersicion genus is comprised of the cultivated tomato, L. esculentum and several closely related wild species that differ in fruit color and their ability to be easily crossed with [...]