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Community stroke rehabilitation (CSR) is an effective program for survivors to recover at home supported by a multidisciplinary team. A home-based, specialized CSR program was delivered in Windsor, Ontario, to stroke patients who faced barriers to accessing outpatient services following inpatient rehabilitation. Preliminary results show program patients made significant functional improvements from baseline to program discharge. A subgroup analysis revealed that, after adjusting for age and resource intensity, moderate to severe stroke patients made greater functional gains compared to mild stroke patients. The individualized focus of CSR delivered in the home provides an effective model of rehabilitation for continued stroke care in the community.
Spherical Sn0.3Ag0.7Cu (wt.%) solder droplets with diameter ranging from 70.6 to 334.0 µm were prepared using pulsated orifice ejection method. Compared with conventional atomization, these droplets are almost completely spherical with a much narrower size distribution. The surface of these droplets is smooth without detectable satellite particles. Furthermore, both the composition and microstructure are homogenous throughout any single droplet regardless of their size. Detailed microstructural analysis shows that nano-sized Ag3Sn particles are distributed homogenously in the β-Sn matrix. The results suggest that the droplets have advantage as electronic packaging material and be a promising candidate material for three-dimensional printing.
Gruenberg and Linnell showed that the standard relation module of a free product of n groups of the form Cr ×
could be generated by just n + 1 generators, raising the possibility of a relation gap. We explicitly give such a set of generators.
To develop a regime of care for patients with head and neck cancers undergoing intensity-modulated radiotherapy (IMRT), with the support of a health advisor (HA) and temporary access to the mouth care product Caphosol™.
Materials and methods
A HA was temporarily employed to assess, monitor and refer patients as appropriate and ensure patients received and utilised supplies of Caphosol™. A retrospective audit was undertaken to provide a gap analysis of current service. The data were used to develop a pro forma for documenting assessments and monitoring lifestyle factors for IMRT patients. Assessments referrals and compliance, plus hospital admissions owing to treatment-related issues, were documented during the baseline audit and the temporary HA service and provision of Caphosol™.
The presence of a HA facilitated 100% compliance with appropriate assessments, referrals and adherence to treatment. The data suggests that the additional provision of Caphosol™ may have reduced levels of mucositis and associated pain.
It is recommended that a HA role be established within radiotherapy departments to facilitate lifestyle assessments, referrals and compliance with positive behaviour changes (e.g., stopping smoking). The use of Caphosol™ as a routine part of mouth care regime for IMRT patients also warrants further investigation.
Large-area Cu2ZnSnS4 (CZTS) thin films were deposited by low-cost spray pyrolysis technique on Mo-coated soda-lime glass (SLG) substrates at varied substrate temperatures of 563-703°K. Deposition conditions were optimized to obtain best quality films and effect of post deposition thermal processing of the as-deposited films under H2S ambient were investigated. Structural, morphological, and compositional characterization of as-deposited and H2S treated CZTS absorber layers were carried out by x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDX). Optical and electrical properties were measured by UV-Vis spectroscopy, van der Pauw, and Hall-effect measurements. Films grown at ∼360°C substrate temperature showed superior optoelectronic properties, improved stoichiometry and smoother morphology compared to films grown at much higher or lower temperatures. Film properties were significantly improved after the H2S processing. Our results show that large area high quality CZTS films can be fabricated by low-cost spray pyrolysis technique for high throughput commercial production of CZTS based heterojunction solar cells.
A theoretical investigation of both deterministic and statistical approaches to modulational instability arising in the cylindrical nonlinear von Neumann equation (CNLvNE) is carried out. This is done on the basis of a recently discovered exact mapping that relates the CNLvNE to the standard one. We show that the dispersion relations of the cylindrical case (for the examples considered here) do not depend explicitly on time and their functional forms do not change with respect to the corresponding standard cases. These results differ from the previous investigations.
Recently, a theoretical investigation of the collective and nonlocal quantum effects has been carried out within the framework of a quantum approach to the relativistic charged particle beam travelling in a cold, collisionless, strongly magnetized plasma. This has been done taking into account both the plasma wake field excitation and the quantum paraxial approximation. On the basis of this theory, here we carry out a preliminary study of the transverse effects experienced by a cold relativistic beam through a thin plasma slab (plasma lens). In the strongly nonlocal regime, in which the beam experiences a very strong focusing effect, the scheme of plasma lens is reviewed in terms of the wave description provided by the above quantum theory.
A theoretical investigation of the basic characteristics of cylindrical and spherical dust-ion-acoustic (DIA) solitary waves (SWs) is made in a dusty non-thermal plasma, whose constituents are non-thermal electrons, inertial ions, and arbitrarily charged stationary dust. The reductive perturbation method is used to derive the modified Gardner equation. The latter is numerically analyzed for both positively and negatively charged dust. The basic features of cylindrical and spherical DIA SWs, which are found to exist in such a dusty non-thermal plasma, are identified. The implications of our results to both space and laboratory plasma situations are also discussed briefly.
Due to environmental concerns traditional eutectic tin-lead solder is gradually being replaced in electronic assemblies by “lead-free” solders. During this transition, nanoparticle technology is also being investigated to see whether improvements in joint reliability for high temperature applications can be made. Nanoparticles can be used to harden the solder via Zener pinning of the grain boundaries and reduce fatigue failure. This paper explores the effects of adding Silica nanoparticles to SnAgCu solder, and how the mechanical properties induced in the solder vary with temperature. It is found that above 100 °C the mechanical response and microstructure of the normal and nanoparticle enhanced solders converge.
Recently the Sunda clouded leopard Neofelis diardi was recognized as a separate species distinct from the clouded leopard Neofelis nebulosa of mainland Asia. Both species are categorized as Vulnerable on the IUCN Red List. Little is known about the newly identified species and, in particular, information from forests outside protected areas is scarce. Here we present one of the first density estimates calculated with spatial capture–recapture models using camera-trap data. In two commercial forest reserves in Sabah (both certified for their sustainable management practices) the density of the Sunda clouded leopard was estimated to be c. 1 per 100 km2 (0.84±SE 0.42 and 1.04±SE 0.58). The presence of the Sunda clouded leopard in such forests is encouraging for its conservation but additional studies from other areas, including protected forests, are needed to compare and evaluate these densities.
Owing to their superior strength in comparison to other single phase intermetallics, NiAl-Ni2AlTi alloys have potential for the matrix material in high temperature composites. An investigation of two compositions, Ni-40Al-10Ti and Ni-45Al-5Ti with and without 20 vol. pct. TiB2 in the form of −1μm diameter particles, was initiated with materials produced by the Martin Marietta XDTM process and compacted by hot pressing. The as fabricated materials were fully dense and polycrystalline where the grain sizes measured −8μm for Ti-poor and about 15μm for the Ti-rich unreinforced materials but could not be determined for ei her TiB2-containing composite. Elevated temperature compression testing was conducted to approximately 8 percent deformation between 1200 and 1400 K with strain rates varying from −10−4 to −10−7 s−1. While the majority of the tests exhibited diffuse yielding over approximately one percent strain followed by negative strain hardening, a few experiments resulted in steady state behavior where deformation continued under a constant stress. The flow strengths on yielding of both forms of Ni-40Al-1OTi were higher than those for the Ni-45Al-5Ti versions. Although for each matrix composition the addition of 20 vol. pct. TiB2 decreased the strength at the higher strain rates in comparison to the TiB2-free forms, the particles do provide reinforcement during slow deformation conditions. Optical microscopy of tested specimens revealed that these materials are generally quite brittle as numerous longitudinal and transverse cracks were found irrespective of the type of stress-strain behavior.
The mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.
To enhance the high temperature strength of aluminides, NiAl–iB2 composites with particulate contents up to 30 vol. pct. were made by XDTM synthesis and hot pressed to full density. Microstructures of these composites were characterized by optical, scanning and transmission electron microscopy (TEM). The average size of the TiB2 particles was about 1 μm, and the average grain size of the NiAl matrix was on the order of 10 μm. Elevated temperature compression testing was conducted on these composites in air at 1200 and 1300 K with strain rates varying from −10−4 to −10−7 s−1. Flow strengths were found to increase with increasing TiB2 content; for example, the 20 vol. pct. TiB2 composite was three times stronger than unreinforced NiAl. Post test TEM analysis showed that the primary feature of the dislocation substructure of deformed NiAl was well defined subgrain boundaries, whereas the structure of the higher volume fraction composites consisted of a very high density of tangled dislocations, loops and subgrain boundaries connecting particles. These observations suggest that TiB2 particles can stabilize a completely different dislocation structure than that normally found in NiAl.
The realization theorem asserts that for a finitely presented group G, the D(2) property and the realization property are equivalent as long as G satisfies a certain finiteness condition. We show that the two properties are in fact equivalent for all finitely presented groups.
Type 2 diabetes is commoner in Asians than Caucasians. Many nitrosamines are diabetogenic, causing both type 2 and type 1 diabetes. Of CD1 mice fed with betel-nut or associated nitrosamines 8·5 % develop glucose intolerance with marked obesity. Glycaemia and anthropometric risk markers for type 2 diabetes were therefore examined in relation to betel usage in 993 ‘healthy’ Bangladeshis by one bilingual research-worker (N.M.). Of these, 12 % had known diabetes. A further 145 of 187 subjects ‘at-risk’ of diabetes (spot glucose >6·5 mmol/l <2 h after food, or >4·5 mmol/l >2 h after food) had a second blood glucose sample taken; sixty-one were confirmed as ‘at-risk’, and had an oral glucose tolerance test; nine new diabetics were identified. Multiple regression analysis showed that spot blood glucose values decreased with time after eating (P = 0·0005) and increased independently with waist size (P = 0·0005) and age (P = 0·0005) without relationships to other aspects of the diet, season or smoking. Waist size was strongly related to betel usage independent of other factors such as age. Betel use interacted with sex, relating to increasing glycaemia only in females. Since waist and age were the major markers of increasing glycaemia we suggest that betel chewing, a habit common to about 10 % of the world population (more than 200 million people) may contribute to the risk of developing type 2 diabetes mellitus.
Since 1976 NiAl–Ni2AlTi alloys have been known to possess elevated temperature mechanical properties approaching those of Ni-base superalloys; however, due to their apparent brittleness, little additional work has been undertaken to exploit this strength. In an attempt to instill ductility in these materials, small grain size single (Ni–45Al–5Ti) and two (Ni–40Al–10Ti) phase intermetallics were fabricated by XDTM technology and tested (XDTM is a trademark of Martin Marietta Corporation). As these compositions have the potential for being the matrix material in high temperature composites, Ni–40Al–10Ti and Ni–45Al–5Ti with 20 vol.% TiB2 in the form of ∼1 μm diameter particles were also investigated. The as-fabricated materials were fully dense and polycrystalline. The grain sizes measured ∼8 μm for Ti-poor and about 15 μm for the Ti-rich unreinforced materials but could not be determined for either TiB2 containing composite. Elevated temperature compression testing was conducted to about 8% deformation between 1200 and 1400 K with strain rates varying from ∼10−4 to ∼10−7 s−1. The majority of the tests exhibited diffuse yielding over approximately 1% strain followed by negative strain hardening. However, a few experiments resulted in steady state behavior where deformation continued under a constant stress. The flow strengths on yielding of both forms of Ni–40Al–10Ti were higher than those for the Ni–45Al–5Ti versions. For each matrix composition the addition of 20 vol.% TiB2 decreased the strength at the higher strain rates in comparison to the TiB2-free forms. During slow deformation conditions, however, the particles do provide reinforcement. Light optical microscopy of tested specimens revealed that these materials are generally quite brittle as numerous longitudinal and transverse cracks were found irrespective of the type of stress-strain behavior.
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