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Antidepressant use has risen x3-5 in Western countries since the early 1990s, outstripping changes in depression incidence or prevalence. This represents a major public health challenge.
Nationally-collected antidepressant data were used to assess the impact of "Doing Well", (DW) a novel depression care programme operating in Renfrewshire, Scotland. "Doing Well" implemented a model of “stepped collaborative care”, practitioner education and significant service redesign. Prescribing was compared for three groups: "DW" (76,000 population; clinical and educational intervention), "DW neighbours” (101,000 population; educational interventions only), and Scotland (no specific intervention).
A national rise in antidepressant prescriptions was stabilised for the "DW" group (graph). Antidepressant cost/item fell by 42% and 40% in both “DW” and “DW neighbours” groups but rose by 8% nationally.
Access to clinical interventions are required to reduce antidepressant prescriptions, but cost savings may be made with educational interventions alone.
Virtual Engineering (VE), also known as Model-Based Systems Engineering (MBSE), is necessary in both current operational engineering qualifications and to help reduce the costs of future vertical lift design and analysis. As computational power continues to provide increasing capability to the rotorcraft engineering community to perform simulations in both real time and off line, it is imperative that the community develop verification and validation protocols and processes to certify these methods so that they can be reliably used to help reduce engineering cost and schedule. Computational Fluid Dynamics (CFD) has become a major Computational Science and Engineering (CSE) tool in the fixed wing and vertical lift communities, but it has not been developed to the point where it is accepted as a replacement for testing in certification of new or existing systems or vehicles. Since the rise of modern CFD in the 1980s, the promise of CFD’s capabilities has been met or exceeded, but its role in certification arguably remains less prominent than projected. The ability to implement transformative technologies further drives the need for CFD in design. To meet CFD’s role in certification, several goals must be met to provide a true “numerical experiment” from which accuracies (error estimates), sensitivities, and consistent application results can be extracted. This paper discusses the progress and direction towards developing CFD strategies for certification.
Introduction: Emergency department (ED) overcrowding is a common and complicated challenge for EDs worldwide. Nurse-initiated protocols, diagnostics and/or treatments implemented by nurses prior to patients being seen by a physician or nurse practitioner, have been suggested as a potential strategy to improve patient flow. Methods: This randomized, pragmatic, controlled evaluation of 5 nurse-initiated protocols occured in a crowded inner-city ED. Six physicians and 44 registered nurses, 3 clinical nurse educators and 3 unit managers were involved in revising 5 patient-complaint focused protocols prior to evaluation. Thirty (30/180) emergency nurses were provided 1 hour of training on inclusion and exclusion criteria, procedure and evaluation methods. Data was abstracted in a manner concealing patient allocation. Primary outcomes evaluated included time to diagnostic test, treatment, consultation or ED length of stay. This evaluation was completed following both the CONSORT and SQUIRE guidelines. Results: Time to acetaminophen for the intervention group (n=11) was 1h:04 min on average (95%CI 30min to 1h:37min) whereas the control group (n=9) was 3h:35min (95%CI 2h:21min to 4h:48min). The average length of stay of a suspected fractured-hip in the intervention group (n=5) was 3h:34min (95%CI 1h:49min to 5h:19min) and 7h:34min for the control group (n=4) was (95%CI 5h:26min to 9h:42min). Time to troponin in the intervention group (n=29) was one quarter (average 48min, 95% CI 32min to 64min) of the time it was in the control group (n=14) (average 3h:16min, 95%CI 1h:53min to 4h:39min; p < 0.001). The vaginal bleeding in pregnancy protocol reduced length of stay by roughly fifty-percent; the intervention group (n=11) had a length of stay of 4h:57min (95%CI 3h:46min to 6h:08min) compared to 8h:33min (95% CI 6h:23min to 10h:44min) for the control (n=7) (p < 0.001). There was no statistical difference in the length of stay for patients who received protocolized diagnostics for abdominal pain. Conclusion: Targeting specific patient groups with carefully written protocols can improve the timeliness of care. A cooperative and collaborative interdisciplinary group are essential to success. Having a system in place to ensure ongoing quality in protocol application and interdisciplinary support has proven more difficult than improving the primary outcomes in this evaluation.
The radio emission associated with SN 1987A appears to be synchrotron emission resulting from the acceleration of electrons at the interface between the outward moving shock wave and clumps of circumstellar material. The Australia Telescope Compact Array is now able to resolve this region, which has dimensions of ~ arcsec, revealing a slight (10%) asphericity in the distribution of the low density gas within the [OIII] circumstellar ring. Assuming that the radio emission arises from a region just behind the shock front, we deduce a mean radial expansion velocity, from 1987 to 1992, of 29 200 kms. First observed contact of the shock with the [OIII] circumstellar ring could occur as early as mid-1993, depending on the deceleration in the intervening gas. This will probably be closely followed by shock-excited optical lines, a strong X-ray outburst and a further increase in the radio emission.
We have examined the properties of helium bubbles in Fe using two different Fe-He potentials. The atomic configurations and formation energies of different He-vacancy complexes are determined and their stability in the region of nearby collision cascades is investigated. The results show that the optimal He to Fe vacancy ratio increases from about 1:1 for approximately 5 vacancies up to about 4:1 for 36 vacancies. Collision cascades initiated near the complex show that Fe vacancies produced by the cascades readily become part of the He-vacancy complexes. The energy barrier for an isolated He interstitial to diffuse was found to be 0.06 eV. Thus a possible mechanism for He bubble growth would be the addition of vacancies during a radiation event followed by the subsequent accumulation of mobile He interstitials produced by the corresponding nuclear reaction.
The preparation of site-specific atom-probe tomography (APT) samples containing localized features has become possible with the use of focused ion beams (FIBs). This technique was used to achieve the analysis of surface oxides and oxidized grain boundaries in this paper. Transmission electron microscopy (TEM), providing microstructural and chemical characterization of the same features, has also been used, revealing crucial additional information.
The study of grain boundary oxidation in stainless steels and nickel-based alloys is required in order to understand the mechanisms controlling stress corrosion cracking in nuclear reactors. Samples oxidized under simulated pressurized water reactor primary water conditions were used, and FIB lift-out TEM and APT specimens containing the same oxidized grain boundary were prepared and fully characterized. The results from both techniques were found fully consistent and complementary.
Chromium-rich spinel oxides grew at the surface and into the bulk material, along grain boundaries. Nickel was rejected from the oxides and accumulated ahead of the oxidation front. Lithium, which was present in small quantities in the aqueous environment during oxidation, was incorporated in the oxide. All phases were accurately quantified and the effect of different experimental parameters were analysed.
We use spectroscopic imaging to investigate the enhancement of infra-red to visible upconversion in rare-earth doped nano-particles (NaYF4:Yb:Er) supported on nano-fabricated plasmonic substrates consisting of square lattices of Au nano-pillars fabricated by electron beam lithography and designed to support a surface plasmon polariton at frequencies which are nearresonant with the rare-earth ion (Yb3+) absorption. We observe a systematic enhancement in the efficiency of upconversion associated with the interaction of the co-doped nano-particles with the plasmonic substrate. Spectrally-resolved imaging provides a massively parallel means of assessing the range of achievable enhancement and its relation to the specific configuration of the substrate / upconverting nano-particle system. Spectrally-resolved reflectivity of the plasmonic substrates confirms the role of the surface plasmon polariton in the upconversion enhancement. Experimental results are compared to Finite Difference Time Domain simulations of the frequency-dependent reflectivity of these metallic nanostructures.
SN1987A has an intrinsic radio luminosity some four orders of magnitude less than SN1993J at maximum, largely a reflection of the tenuous wind . from the progenitor of SN1987A before explosion. Both remnants have an edge-brightened, ring-like morphology though, in the case of SN1987A, the expansion rate is currently only around 3500 km s−1. The flux density of the remnant of SN1987A continues to rise at all measured radio frequencies. Its spectral index is gradually flattening, indicating its transition into the supernova remnant phase. A campaign to increase the resolution of radio imaging by observing at higher frequencies is underway with the Australia Telescope Compact Array (ATCA).
Tissues from barred tiger salamanders (Ambystoma tigrinum mavortium), Great Plains toads (Bufo cognatus) and New Mexico spadefoots (Spea multiplicata) collected from 16 playa wetlands in Texas during 1999 and 2000 were examined by light microscopy. Digenean cysts were primarily distributed subcutaneously throughout the specimens and occasionally coelomic invasion was noted. The parasites within the cysts were 1.5–2 mm in diameter, with a thin (c. 10 μm wide) eosinophilic-staining tegument, two suckers (oral and ventral), posteriorly located primordial genitalia and paired digestive caeca. These digeneans were identified as the metacercariae of Clinostomum attenuatum. This is the first record of Clinostomum attenuatum in these amphibian species.
Single crystals of Ba8CoRh6O21 were grown out of a potassium carbonate flux. The structure was solved by a general method using the superspace group approach. The superspace group employed was R3m(00γ)0s with a = 10.0431(1) Å, c1 = 2.5946(1) Å and c2 = 4.5405(1) Å, V = 226.60(1) Å3. Ba8CoRh6O21 represents the first example of an m = 5, n = 3 member of the A3n+3mA'nB3m+nO9m+6n family of 2H hexagonal perovskite related oxides and contains chains consisting of six consecutive RhO6 octahedra followed by one distorted CoO6 trigonal prism. These chains in turn are separated from each other by [Ba]∞ chains.
The effects of surface roughness and microsolubility on fouling levels are examined using glass and acrylic samples. It is found that both of these, often overlooked, physical characteristics have a noticeable effect on the rate of fouling. The microsolubility of acrylic results in lower fouling than found on glass despite the higher hydrophobicity of acrylic and the resultant increase in initial attraction for fouling organisms. Fouling levels were found to increase with increasing surface roughness and therefore studies on the fouling susceptibility of different materials should report the roughness values of the samples examined.
Suspensions of colloids obtained from a Spanish bentonite were studied by potentiometric acid-base titrations and electrophoresis in order to analyse their surface chemical properties, which are responsible of their stability behaviour and that are very important to consider in radionuclides sorption modelling.
“Fast” titrations and “batch - back” titrations techniques were used to determine the contribution of the pH - dependent charge and the difference in the results obtained are discussed. Experimental data obtained by acid/base titrations were interpreted according the EDL theory. The model prediction agreed satisfactorily with the experimental data in the alkaline pH range. Protonation / deprotonation reactions of surface functional groups (SOH) appeared to be the main surface charge - determining mechanism in the alkaline pH range whereas ion - exchange type reactions, had to be taken into account over the acidic pH range. Surface potentials were calculated for different salt concentrations, from experimental data and taking into account both layer and edge sites charge contributions.
We are using the 2dF spectrograph to make a survey of all objects (“stars” and “galaxies”) in a 12 deg2 region towards the Fornax cluster. We have discovered a population of compact emission-line galaxies unresolved on photographic sky survey plates and therefore missing in most galaxy surveys based on such material. These galaxies are as luminous as normal field galaxies. Using Hα to estimate star formation they contribute at least an additional 5% to the local star formation rate.
Direct fabrication of metal near-net shapes from a computer model typically involves melting and solidification, which can cause high residual stresses, undesirable phases, poor microstructures, rough surface finishes, warpage, and other problems. This paper describes a new technology, still under development, that might be used to directly fabricate solid, near-fulldensity, free-form shapes of many metals, and even some composite materials, at or near room temperature without melting and solidification. In this process, tentatively called Cold Spray Direct Fabrication (CSDF), powder particles in a supersonic jet of compressed gas impact a solid surface with sufficient energy to cause plastic deformation and consolidation with the underlying material by a process thought to be analogous to explosive welding. Material deposition by cold spray methods has already been successfully demonstrated by several investigators. This paper presents results of an experimental study to investigate the effects of selected process variables on cold spray particle velocities. In addition, a key technical barrier to the CSDF concept is focusing the spray stream down to dimensions that would permit a useful level of part detail, while still providing practical build rates. This paper presents results of initial research to develop an aerodynamic lens that may provide the required particle stream focusing.