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The level scheme and electromagnetic properties of 148Pm have been studied using 149Sm(d, 3He) and 148Nd(p, nγ) reactions. Combining these measurements with estimates for E2/M1 decay branching ratios leads to the tentative conclusion that 148Pmg,m are in thermal equilibrium during the s-process. The branch at 148Pm then leads to an inferred s-process neutron density of 3 × 108 cm−3.
Given the capacity of ruminants to modify diet selection based on metabolic needs, we hypothesised that, when given a choice, lambs experiencing a vitamin E deficiency would consume more of a vitamin E-enriched feed than lambs not deficient in vitamin E. Fifty-six Dohne Merino lambs were divided into two groups and fed either a vitamin E-deficient diet over 40 days to induce low plasma vitamin E or a vitamin E-enriched diet to induce high plasma vitamin E. The lambs were then offered a choice of vitamin E-enriched and vitamin E-deficient pellets. For half of the animals, the enriched diet was paired with strawberry flavour and the deficient diet was paired with orange flavour, while the reverse pairings were offered to the others. Lamb preference for the diets was measured daily for the following 15 days. There was a three-way interaction between the high and low vitamin E treatment groups×vitamin E content and type of flavour in the feed×time (days). The lambs preferred pellets flavoured with strawberry but this preference changed to orange flavour in vitamin E-deficient lambs if the orange flavour was paired with high vitamin E. Lambs without a deficiency continued to prefer strawberry-flavoured pellets, regardless of the vitamin E concentrations in the pellets. It is possible that self-learning contributed to the low vitamin E group of lambs changing preference to orange flavour in order to consume more vitamin E, presumably to remediate the deficiency.
Typical approaches to manipulation of flow separation employ passive means or active techniques such as blowing and suction or plasma acceleration. Here it is demonstrated that the flow can be significantly altered by making small changes to the shape of the surface. A proof of concept experiment is performed using a very simple time-dependent perturbation to the surface of a sphere: a roughness element of 1% of the sphere diameter is moved azimuthally around a sphere surface upstream of the uncontrolled laminar separation point, with a rotational frequency as large as the vortex shedding frequency. A key finding is that the non-dimensional time to observe a large effect on the lateral force due to the perturbation produced in the sphere boundary layers as the roughness moves along the surface is = tU∞/D ≈ 4. This slow development allows the moving element to produce a tripped boundary layer over an extended region. It is shown that a lateral force can be produced that is as large as the drag. In addition, simultaneous particle image velocimetry and force measurements reveal that a pair of counter-rotating helical vortices are produced in the wake, which have a significant effect on the forces and greatly increase the Reynolds stresses in the wake. The relatively large perturbation to the flow-field produced by the small surface disturbance permits the construction of a phase-averaged, three-dimensional (two-velocity component) wake structure from measurements in the streamwise/radial plane. The vortical structure arising due to the roughness element has implications for flow over a sphere with a nominally smooth surface or distributed roughness. In addition, it is shown that oscillating the roughness element, or shaping its trajectory, can produce a mean lateral force.
For Cu - 30 at.% Ni droplets processed by containerless solidification under lévitation, the crystallographic texture correlates strongly with the microstructure seen in optical metallography and with the undercooling at which solidification started. The variation in texture is useful in understanding the development of the microstructure, in particular at the extremes of the undercooling range where grain-refined microstructures are observed.
The nature and origin of lateral composition modulations in (AlAs)m(InAs)n short-period strained-layer superlattices grown by molecular beam epitaxy on InP substrates have been investigated by x-ray diffraction, atomic force microscopy, and transmission electron microscopy. Strong modulations were observed for growth temperatures between ≈ 540 and 560° C. The maximum strength of modulations was found for SPS samples with InAs mole fraction x (= n/(n+m)) close to ≈ 0.50 and when n ≈ m ≈ 2. The modulations were suppressed at both high and low values of x. For x > 0.52 (global compression), the modulations were along the <100> directions in the (001) growth plane. For x < 0.52 (global tension), the modulations were along the two <310> directions rotated ≈ ±27° from  in the growth plane. The remarkably constant wavelength of the modulations, between ≈ 20–30 nm, and the different modulation directions observed, suggest that the origin of the modulations is due to surface roughening associated with the high misfit between the individual SPS layers and the InP substrate. Highly uniform unidirectional modulations have been grown by control of the InAs mole fraction and growth on suitably offcut substrates, which show great promise for application in device structures.
The microstructure of lateral composition modulation in InAs/AlAs superlattices grown by MBE on InP is examined. The use of x-ray diffraction, TEM, AFM, and STEM to characterize the modulations is discussed. Combining the information from these techniques gives increased insight into the phenomenon and how to manipulate it. Diffraction measures the intensity of modulation and its wavelength, and is used to identify growth conditions giving strong modulation. The TEM and STEM analyses indicate that local compositions are modulated by as much as 0.38 InAs mole fraction. Plan-view images show that modulated structures consists of short (≳0.2 μm) In-rich wires with a 2D organization in a (001) growth plane. However, growth on miscut substrates can produce a single modulation along the miscut direction with much longer wires (≲0.4 μm), as desired for potential applications. Photoluminescence studies demonstrate that the modulation has large effects on the bandgap energy of the superlattice.
In August 1988 an increase was noted in the number of cases of cryptosporidiosis identified by the microbiology laboratory at Doncaster Royal Infirmary. By 31 October, 67 cases had been reported. Preliminary investigations implicated the use of one of two swimming pools at a local sports centre and oocysts were identified in the pool water. Inspection of the pool revealed significant plumbing defects which had allowed ingress of sewage from the main sewer into the circulating pool water. Epidemiological investigation confirmed an association between head immersion and illness. The pools were closed when oocysts were identified in the water and extensive cleaning and repair work was undertaken. The pool water was retested for cryptosporidial oocysts and found to be negative before the pool re-opened.
Identifying risk factors for the development of post-traumatic stress disorder (PTSD) is important for understanding and ultimately preventing the disorder. This study assessed pain shortly after traumatic injury (i.e. peritraumatic pain) as a risk factor for PTSD.
Participants (n=115) were patients admitted to a Level 1 Surgical Trauma Center. Admission to this service reflected a severe physical injury requiring specialized, emergent trauma care. Participants completed a pain questionnaire within 48 h of traumatic injury and a PTSD diagnostic module 4 and 8 months later.
Peritraumatic pain was associated with an increased risk of PTSD, even after controlling for a number of other significant risk factors other than acute stress disorder symptoms. An increase of 0.5 s.d. from the mean in a 0–10 pain rating scale 24–48 h after injury was associated with an increased odds of PTSD at 4 months by more than fivefold, and at 8 months by almost sevenfold. A single item regarding amount of pain at the time of hospital admission correctly classified 65% of participants.
If these findings are replicated in other samples, high levels of peritraumatic pain could be used to identify individuals at elevated risk for PTSD following traumatic injury.
Health care reform has been stalled since the Clinton health care initiative, but the political difficulties internal to that initiative and the ethical problems that provoked it -- of cost, coverage, and overall fairness, for example -- have only gotten worse. This collection examines the moral principles that must underlie any new reform initiative and the processes of democratic decision-making essential to successful reform. This volume provides careful analyses that will allow the reader to short-circuit the mythmaking, polemics, and distortions that have too often characterized public discussion of health care reform. Its aim is to provide the moral foundations and institutional arrangements needed to drive any new health care initiative and so to stimulate a reasoned discussion before the next inevitable round of reform efforts.
Foreword by Thomas H. Murray. Contributors: Howard Brody, Norman Daniels, Theodore Marmor, Tobie H. Olsan, Uwe E. Reinhardt, Gerd Richter, Rory B. Weiner, Lawrence W. White
Wade L. Robison is the Ezra A. Hale Professor in Applied Ethics at the Rochester Institute of Technology and recipient of the Nelson A. Rockefeller Prize for Social Science and Public Policy for his book Decisions in Doubt: The Environment and Public Policy. Timothy H. Engström is Professor of Philosophy at the Rochester Institute of Technology and recipient of the Eisenhart Award for Outstanding Teaching.