The mid-infrared extinction law in the darkest cores of the Pipe Nebula

Context. The properties of dust grains, in particular their size distribution, are expected to differ from the interstellar medium to the high-density regions within molecular clouds. Aims. We measure the mid-infrared extinction law produced by dense material in molecular cloud cores. Since the extinction at these wavelengths is caused by dust, the extinction law in cores should depart from that found in low-density environments if the dust grains have different properties. Methods. We use the unbiased LINES method to measure the slope of the reddening vectors in color-color diagrams. We derive the mid-infrared extinction law toward the dense cores B59 and FeSt 1-457 in the Pipe Nebula over a range of visual extinction between 10 and 50 magnitudes, using a combination of Spitzer/IRAC, and ESO NTT/VLT data. Results. The mid-infrared extinction law in both cores departs significantly from a power-law between 3.6 and 8 micron, suggesting that these cores contain dust with a considerable fraction of large dust grains. We find no evidence for a dependence of the extinction law with column density up to 50 magnitudes of visual extinction in these cores, and no evidence for a variation between our result and those for other clouds at lower column densities reported elsewhere in the literature. This suggests that either large grains are present even in low column density regions, or that the existing dust models need to be revised at mid-infrared wavelengths. We find a small but significant difference in the extinction law of the two cores, that we tentatively associate with the onset of star formation in B59.Comment: 8 pages, 6 figures. Accepted to A&

Faceting and structural anisotropy of nanopatterned CdO(110) layers

CdO(110) layers with a self-organized surface structure have been grown on (10math0) sapphire (m plane) substrates by metal-organic vapor phase epitaxy. The epitaxial relationships between layer and substrate have been determined and a crystallographic model that accounts for the CdO in-plane orientation, which results in a reduced lattice mismatch when the CdO[001] direction is perpendicular to the sapphire c axis, has been proposed. Although the measured lattice parameters indicate that the layers are almost fully relaxed, an anisotropic mosaicity is detected with symmetrical rocking curves attaining minimum values when measured along the CdO[math10] direction. The layer morphology consists of a regular ridge-and-valley structure which defines, again, a preferential in-plane direction. The grooves run parallel to the CdO[001] axis and exhibit lateral surfaces sloped at 28° with respect to the (110) surface. The influence of growth temperature and VI∕II molar ratio on the anisotropic mosaicity and morphology has been [email protected] [email protected] [email protected]

Bandgap and effective mass of epitaxial cadmium oxide

The bandgap and band-edge effective mass of single crystal cadmium oxide, epitaxially grown by metal-organic vapor-phase epitaxy, are determined from infrared reflectivity, ultraviolet/visible absorption, and Hall effect measurements. Analysis and simulation of the optical data, including effects of band nonparabolicity, Moss-Burstein band filling and bandgap renormalization, reveal room temperature bandgap and band-edge effective mass values of 2.16±0.02 eV and 0.21±0.01m0 respectively

Improving patient activation with a tailored nursing discharge teaching intervention for multimorbid inpatients: A quasi-experimental study.

Preliminary effectiveness test of a novel structured personalized discharge teaching intervention for multimorbid inpatients. Using a 2-group sequential pre/post-intervention design, the sample comprised 68 pre-intervention control group and 70 post- intervention group participants. The discharge teaching intervention by trained clinical nurses used structured tools to engage patients and individualize discharge teaching. Outcomes measures included Patient Activation Measure, Readiness for Hospital Discharge Scale, Discharge Care Experiences Survey, and readmission with 10 days post-discharge. The intervention had a statistically significant positive effect on improving patient activation (M=4.8; p = 0.05) from admission to post-discharge. The participation subscale of the Discharge Care Experiences Survey was higher in the intervention (M=4.1, SD=0.7) than the control group (M=3.8, SD=0.7; t (127)= -2.79, p = .01, effect size= .34). There were no significant between-group differences in Readiness for Hospital Discharge Scale and readmission. Our results suggest that a structured personalized discharge teaching intervention can improve patient activation and participation in discharge care. Further refinement of the intervention is needed to evaluate and improve specific components of the intervention. Structured personalized discharge teaching should include patient engagement strategies in the teaching-learning process

A homopolar disc dynamo experiment with liquid metal contacts

We present experimental results of a homopolar disc dynamo constructed at CICATA-Quer\'etaro in Mexico. The device consists of a flat, multi-arm spiral coil which is placed above a fast-spinning metal disc and connected to the latter by sliding liquid-metal electrical contacts. Theoretically, self-excitation of the magnetic field is expected at the critical magnetic Reynolds number Rm~45, which corresponds to a critical rotation rate of about 10 Hz. We measured the magnetic field above the disc and the voltage drop on the coil for the rotation rate up to 14 Hz, at which the liquid metal started to leak from the outer sliding contact. Instead of the steady magnetic field predicted by the theory we detected a strongly fluctuating magnetic field with a strength comparable to that of Earth's magnetic field which was accompanied by similar voltage fluctuations in the coil. These fluctuations seem to be caused by the intermittent electrical contact through the liquid metal. The experimental results suggest that the dynamo with the actual electrical resistance of liquid metal contacts could be excited at the rotation rate of around 21 Hz provided that the leakage of liquid metal is prevented.Comment: 6 pages, 5 figures (to appear in Magnetohydrodynamics