Social Work handbook

2002 handbook for the Board of Studies in Social Wor

Observation of strongly entangled photon pairs from a nanowire quantum dot

A bright photon source that combines high-fidelity entanglement, on-demand generation, high extraction efficiency, directional and coherent emission, as well as position control at the nanoscale is required for implementing ambitious schemes in quantum information processing, such as that of a quantum repeater. Still, all of these properties have not yet been achieved in a single device. Semiconductor quantum dots embedded in nanowire waveguides potentially satisfy all of these requirements; however, although theoretically predicted, entanglement has not yet been demonstrated for a nanowire quantum dot. Here, we demonstrate a bright and coherent source of strongly entangled photon pairs from a position controlled nanowire quantum dot with a fidelity as high as 0.859 +/- 0.006 and concurrence of 0.80 +/- 0.02. The two-photon quantum state is modified via the nanowire shape. Our new nanoscale entangled photon source can be integrated at desired positions in a quantum photonic circuit, single electron devices and light emitting diodes.Comment: Article and Supplementary Information with open access published at: http://www.nature.com/ncomms/2014/141031/ncomms6298/full/ncomms6298.htm

Societal Utilities for Cognitive Impairment in Schizophrenia:Developing a Preference-Based Scoring Algorithm Based on the Schizophrenia Cognition Rating Scale

Introduction: Loss of cognitive function is a common feature in schizophrenia. However, generic measures of health-related quality of life favored by decision-makers, such as the EQ-5D, are not designed to detect changes in cognitive function. We report the valuation of the Schizophrenia Cognition Rating Scale (SCoRS), a schizophrenia-specific measure of cognitive impairment.Methods: Expert opinion and psychometric analysis of the SCoRS from clinical trial data was undertaken to select 5 key items from the measure. These items were combined orthogonally to develop health-state vignettes. Vignettes were valued using composite time trade-off (cTTO) in one-on-one video calls. Several econometric models were fitted to the data to estimate disutilities. Performance of EQ-5D- and SCoRS-based utilities were compared in the trial data. Results: The SCoRS items selected for the valuation study represented attention, learning, processing speed, social cognition and memory. Four hundred respondents participated in the valuation study. The best observed health state was valued at 0.855 [standard deviation (SD) = 0.179] and the worst at 0.152 (SD = 0.575). At the most severe levels, ‘social cognition’ received the largest disutility followed by ‘learning’ and ‘memory’. The final model to estimate utilities had 15 parameters. SCoRS-based utilities were sensitive to change in cognition, but the EQ-5D was not. Conclusion: It is feasible to value different dimensions of cognition separately using a validated instrument for proxy assessment. The resulting utilities indicate loss of quality of life due to reduced cognitive functioning.</p

Dinoflagellate cysts production, excystment and transport in the upwelling off Cape Blanc (NW Africa)

To extend the understanding of dinoflagellate cysts production, excystment and vertical/lateral transport in the water column, we compared upper water cyst export production with cysts associations and concentrations in the subsurface nepheloid layer, bottom nepheloid layer and deeper water column during active upwelling off Cape Blanc (NW Africa) in August 2020. Export production was collected by two drifting trap surveys; DTS1 in an active upwelling cell for 4 days and DTS2 in an offshore drifting upwelling filament for 2 days. Subsurface, bottom nepheloid layers and deeper waters were sampled by in-situ pumps along two transects perpendicular to the shelf break. During DTS1, light limitation hampered phytoplankton production which might have influenced cyst production negatively due to up- and downward movement of water masses. Cyst export production increased at the rim of the upwelling cell. For DTS2, upwelling filament cyst export production was up to 3 times lower than that of DTS1. Echinidinium delicatum had highest relative and absolute abundances in the active upwelling, Echinidinium zonneveldiae and Bitectatodinium spongium in the upwelling filament, and Impagidinium spp. and cysts of Gymnodinium microreticulatum/nolleri at the most distal stations. Comparison of concentrations of cysts with and without cell contents showed that the majority of cysts hatched before reaching deeper waters and displayed a dormancy period of less than 6 days. About 5% of the living cysts reached deeper waters and/or the ocean floor. Living cysts were transported offshore in the upwelling filament. In case ships exchange ballast waters in the studied region, they will take up laterally transported living cysts. Upon release of the ballast waters in the port of arrival, these cysts have the potential to become “invader species” that can threaten economy and/or health. Lateral transport of cysts was observed in the bottom nepheloid layer and in deeper waters (800 - 1200m depth) with a maximal extension of about 130km off the shelf break. Therefore, sediments in the region will contain a mixture of regionally and locally produced dinoflagellate cysts. This insight contributes to the improvement of environmental reconstructions of the Cape blanc upwelling system based on downcore cyst associations

Motor Development of Premature Infants Born between 32 and 34 Weeks

Little is known about motor development in late preterm born infants. Our objective was to determine long-term outcome of motor skills of infants born between 32 and 34 weeks. All infants were assessed at corrected ages of 3 and 9 months, using the Alberta Infant Motor Scale. At corrected ages of 4 years, the Movement Assessment Battery for Children was done. Seventy infants were seen at 4 years of age (median of 3 assessments per infant). Abnormal assessment at 3 or 9 months of age resulted in normal outcome in almost 80% at 4 years. On the other hand, a normal outcome in the first year of life resulted in an abnormal outcome at 4 years in 10% of the infants. Our results suggest that long-term followup of these late preterm born infants is necessary, as the assessments in the first year do not predict the long-term outcome

Cardiologist and cardiac surgeon view on decision-making in prosthetic aortic valve selection: does profession matter?

Cardiolog

Forces between clustered stereocilia minimize friction in the ear on a subnanometre scale

The detection of sound begins when energy derived from acoustic stimuli deflects the hair bundles atop hair cells. As hair bundles move, the viscous friction between stereocilia and the surrounding liquid poses a fundamental challenge to the ear's high sensitivity and sharp frequency selectivity. Part of the solution to this problem lies in the active process that uses energy for frequency-selective sound amplification. Here we demonstrate that a complementary part involves the fluid-structure interaction between the liquid within the hair bundle and the stereocilia. Using force measurement on a dynamically scaled model, finite-element analysis, analytical estimation of hydrodynamic forces, stochastic simulation and high-resolution interferometric measurement of hair bundles, we characterize the origin and magnitude of the forces between individual stereocilia during small hair-bundle deflections. We find that the close apposition of stereocilia effectively immobilizes the liquid between them, which reduces the drag and suppresses the relative squeezing but not the sliding mode of stereociliary motion. The obliquely oriented tip links couple the mechanotransduction channels to this least dissipative coherent mode, whereas the elastic horizontal top connectors stabilize the structure, further reducing the drag. As measured from the distortion products associated with channel gating at physiological stimulation amplitudes of tens of nanometres, the balance of forces in a hair bundle permits a relative mode of motion between adjacent stereocilia that encompasses only a fraction of a nanometre. A combination of high-resolution experiments and detailed numerical modelling of fluid-structure interactions reveals the physical principles behind the basic structural features of hair bundles and shows quantitatively how these organelles are adapted to the needs of sensitive mechanotransduction.Comment: 21 pages, including 3 figures. For supplementary information, please see the online version of the article at http://www.nature.com/natur