Given evidence that early executive functioning sets the stage for a broad range of subsequent outcomes, researchers have sought to identify ways to foster these cognitive capacities. The current ...series of studies sought to design, develop, and provide evidence for the efficacy of embedding cognitive activities in a commonplace activity—shared reading of a children's book. The book, Quincey Quokkcfs Quest, required children to control their thinking and behavior to help the story's main character through a series of obstacles. The first study investigated effects of reading with embedded cognitive activities in individual and group contexts on young children's executive functions (EFs). The second study compared reading with embedded cognitive activities against a more active control condition (dialogic reading) that similarly engaged children in the reading process yet lacked clear engagement of EFs. The third study sought to investigate whether the effect of reading the story with embedded EF activities changed across differing doses of the intervention and whether effects persisted 2 months post-intervention. All studies provided evidence of intervention effects on shifting, with working memory benefits shown in two of the three studies, in as little as 3 weeks (compared to more traditional reading). Study 3 further indicated maintenance of these gains 2 months later. This suggests the efficacy of embedding cognitive activities in the context of everyday activities, thereby extending the range of users and contexts in which this approach can be used.
We present an improved analysis of the final data set from the QUaD experiment. Using an improved technique to remove ground contamination, we double the effective sky area and hence increase the ...precision of our cosmic microwave background (CMB) power spectrum measurements by ~30% versus that previously reported. In addition, we have improved our modeling of the instrument beams and have reduced our absolute calibration uncertainty from 5% to 3.5% in temperature. The robustness of our results is confirmed through extensive jackknife tests, and by way of the agreement that we find between our two fully independent analysis pipelines. For the standard six-parameter Delta *LCDM model, the addition of QUaD data marginally improves the constraints on a number of cosmological parameters over those obtained from the WMAP experiment alone. The impact of QUaD data is significantly greater for a model extended to include either a running in the scalar spectral index, or a possible tensor component, or both. Adding both the QUaD data and the results from the Arcminute Cosmology Bolometer Array Receiver experiment, the uncertainty in the spectral index running is reduced by ~25% compared to WMAP alone, while the upper limit on the tensor-to-scalar ratio is reduced from r < 0.48 to r < 0.33 (95% c.l.). This is the strongest limit on tensors to date from the CMB alone. We also use our polarization measurements to place constraints on parity-violating interactions to the surface of last scattering, constraining the energy scale of Lorentz violating interactions to <1.5 X 10-43 GeV (68% c.l.). Finally, we place a robust upper limit on the strength of the lensing B-mode signal. Assuming a single flat band power between = 200 and = 2000, we constrain the amplitude of B-modes to be <0.57 Delta *mK2 (95% c.l.).
We report results from the second and third seasons of observation with the QUaD experiment. Angular power spectra of the cosmic microwave background are derived for both temperature and polarization ...at both 100 GHz and 150 GHz, and as cross-frequency spectra. All spectra are subjected to an extensive set of jackknife tests to probe for possible systematic contamination. For the implemented data cuts and processing technique such contamination is undetectable. We analyze the difference map formed between the 100 and 150 GHz bands and find no evidence of foreground contamination in polarization. The spectra are then combined to form a single set of results which are shown to be consistent with the prevailing LCDM model. The sensitivity of the polarization results is considerably better than that of any previous experiment-for the first time multiple acoustic peaks are detected in the E-mode power spectrum at high significance.
The forthcoming generation of cosmic microwave background polarization observatories is developing large format detector arrays which will operate at 100 mK. Given the volume of detector wafers that ...will be required, fast-cooldown 100 mK test cryostats are increasingly needed. A miniature dilution refrigerator (MDR) has been developed for this purpose and is reported. The MDR is precooled by a double-stage
3
He
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4
He
Chase Research Cryogenics sorption refrigerator. The test cryostat based on this MDR will enable fast cooldown to 100 mK to support rapid feedback testing of detector wafers fabricated for the Simons Observatory. The MDR has been designed to provide a 100 mK stage to be retrocompatible with existing CRC10 sorption coolers, reducing the base temperature from 250 mK for the new generation of detectors. Other 250 mK cryostats can be retrofitted in the same way. This configuration will meet the cryogenic requirements for single-wafer testing, providing 5–10
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of cooling power at 100 mk for over 8 h. The system operates in a closed cycle, thereby avoiding external gas connections and cold o-rings. No moving parts are required, with the system operated entirely by heaters.
Modern parametric amplifiers are based on lithographically produced superconducting thin-film planar transmission line structures. These paramps rely on resonant structures with embedded nonlinear ...elements to stimulate intermodulation with a stronger pump tone that gives rise to signal gain when certain conditions are satisfied. Such paramps have not yet been realised in superconducting 3D waveguide resonators. Possible applications of these devices include detector systems that are based on 3D waveguide such as dark matter detectors and quantum computers. Reported here are the results of an investigation of a 30.64 GHz series circular waveguide resonance machined from bulk niobium showing parametric gain of up to 2 dB in the presence of a stronger pump tone 10 kHz above in frequency. The gain is largest on abrupt jumps of the transmission spectra of the resonance, which may be a result of weak-link formation on the superconducting surfaces.
We constrain parity-violating interactions to the surface of last scattering using spectra from the QUaD experiment's second and third seasons of observations by searching for a possible systematic ...rotation of the polarization directions of cosmic microwave background photons. We measure the rotation angle due to such a possible "cosmological birefringence" to be 0.55 degrees +/-0.82 degrees (random) +/-0.5 degrees (systematic) using QUaD's 100 and 150 GHz temperature-curl and gradient-curl spectra over the spectra over the multipole range 200<l<2000, consistent with null, and constrain Lorentz-violating interactions to <2 x 10;{-43} GeV (68% confidence limit). This is the best constraint to date on electrodynamic parity violation on cosmological scales.
As the forthcoming generation of Cosmic Microwave Background observatories move towards the use of large format detector arrays operating at ~100 mK, the need for test cryostats capable of operating ...in this temperature regime is becoming more pronounced. This has strongly driven the development of several related systems, including the continuous miniature dilution refrigerator (MDR) reported here. The MDR is comprised of a thermally separated mixing chamber, step heat exchangers, twin stills and twin condensation pumps. The pumps are alternately cooled to ~300 mK by a pair of single-shot 1He sorption coolers (cycled in anti-phase) to circulate 3He in the system. The system is therefore closed-cycle, with the circulation of 3He, both in the MDR and sorption coolers, contained to the cold stage. As a result, the reliability of the system is improved through a mechanically simple design and the absence of external connections, gas handling systems, and cold o-rings.
Centaurus (Cen) A represents one of the best candidates for an isolated, compact, highly polarized source that is bright at typical cosmic microwave background (CMB) experiment frequencies. We ...present measurements of the 4° × 2° region centered on Cen A with QUaD, a CMB polarimeter whose absolute polarization angle is known to an accuracy of 0fdg5. Simulations are performed to assess the effect of misestimation of the instrumental parameters on the final measurement and systematic errors due to the field's background structure and temporal variability from Cen A's nuclear region are determined. The total (Q, U) of the inner lobe region is (1.00 ± 0.07(stat.) ± 0.04(sys.), - 1.72 ± 0.06 ± 0.05) Jy at 100 GHz and (0.80 ± 0.06 ± 0.06, - 1.40 ± 0.07 ± 0.08) Jy at 150 GHz, leading to polarization angles and total errors of -30fdg0 ± 1fdg1 and -29fdg1 ± 1fdg7. These measurements will allow the use of Cen A as a polarized calibration source for future millimeter experiments.
QUaD is a bolometric CMB polarimeter sited at the South Pole, operating at frequencies of 100 and 150 GHz. In this paper we report preliminary results from the first season of operation (austral ...winter 2005). All six CMB power spectra are presented derived as cross spectra between the 100 and 150 GHz maps using 67 days of observation in a low foreground region of approximately 60 deg super(2). These data are a small fraction of the data acquired to date. The measured spectra are consistent with the ACDM cosmological model. We perform jackknife tests that indicate that the observed signal has negligible contamination from instrumental systematics. In addition, by using a frequency jackknife we find no evidence for foreground contamination.
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