799 research outputs found
The Predictability of REIT Returns and Market Segmentatio
A two-factor regression model was used to examine the relationship between returns on healthcare equity REITs (EREITs) and healthcare stocks from 1985 to 1992. General stock indices were incorporated in the model to account for the influence of the market. Multiple positive contemporaneous relationships were found between six of the seven REITs studied and portfolios of other healthcare stocks. Furthermore, in four of the six REITs with positive results, significant correlations were evident between individual REIT portfolios and the SIC indices with which they showed a significant relationship. These results are consistent with a common factor or factors affecting the returns of both healthcare EREITs and stocks. The relationships found between returns on healthcare EREITs and healthcare stocks, especially the correlation between the classification of the EREIT portfolios and SIC indices, indicate the importance of real estate management for healthcare firms and asset subclassification choice for the real estate manager. Although this study specifically investigated healthcare EREITs and healthcare stocks, the results may be more widely applicable to other single-property-type EREITs.
Congestive heart failure in rats is associated with increased expression and targeting of aquaporin-2 water channel in collecting duct
We tested whether severe congestive heart
failure (CHF), a condition associated with excess free-water retention, is accompanied by altered regulation of the vasopressin-regulated water channel, aquaporin-2 (AQP2), in the renal collecting duct. CHF was induced by left coronary artery ligation. Compared with sham-operated animals, rats with CHF had severe heart failure with elevated left ventricular end-diastolic pressures (LVEDP): 26.9 ± 3.4 vs. 4.1 ± 0.3 mmHg, and reduced plasma sodium concentrations (142.2 ± 1.6 vs. 149.1 ± 1.1 mEq/liter). Quantitative immunoblotting of total kidney membrane fractions revealed a significant increase in AQP2 expression in animals with CHF (267 ± 53%, n=12) relative to sham-operated controls (100 ± 13%, n=14). In contrast, immunoblotting demonstrated a lack of an increase in expression of AQP1 and AQP3 water channel
expression, indicating that the effect on AQP2 was selective.Furthermore, postinfarction animals without LVEDP elevation or plasma Na reduction showed no increase in AQP2 expression (121 ± 28% of sham levels, n=6). Immunocytochemistry and immunoelectron microscopy demonstrated very abundant labeling of the apical plasma membrane and relatively little labeling of intracellular vesicles in collecting duct cells from rats with severe CHF, consistent with enhanced trafficking of AQP2 to the apical plasma membrane. The selective increase in AQP2 expression and enhanced plasma membrane targeting provide an explanation for the development of water retention and hyponatremia in severe
CHF
Effects of rf Current on Spin Transfer Torque Induced Dynamics
The impact of radiofrequency (rf) currents on the direct current (dc) driven
switching dynamics in current-perpendicular-to-plane nanoscale spin valves is
demonstrated. The rf currents dramatically alter the dc driven free layer
magnetization reversal dynamics as well as the dc switching level. This occurs
when the frequency of the rf current is tuned to a frequency range around the
dc driven magnetization precession frequencies. For these frequencies,
interactions between the dc driven precession and the injected rf induce
frequency locking and frequency pulling effects that lead to a measurable
dependence of the critical switching current on the frequency of the injected
rf. Based on macrospin simulations, including dc as well as rf spin torque
currents, we explain the origin of the observed effects.Comment: 5 pages, 4 figure
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NPD, design and management for SME's
It is generally acknowledged that small and medium sized enterprises (SME's) contribute significantly to a country’s economic performance. It is also generally acknowledged that it can be problematic to provide effective, public sector research, development and innovation support for SME's given their size and diversity. It is also considered that vertical cooperation with customers and suppliers is more effective in new product development (NPD) for SME's than horizontal co-operation with research institutions and government agencies. This paper discusses how higher education institutions (HEI's) engaged in design research, can effectively support SME's in NPD by actively participating in the design process whilst simultaneously working with SME's to facilitate the development of knowledge networks local to specific SME's, by acting as an intermediary. A number of design support schemes and specific SME, NPD projects undertaken by the author are used to advocate a participatory intermediation role for HEI's in supporting NPD for SME's
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The need for a holistic approach to sustainability in new product development from the designers perspective
There are a growing number of tools available to the Product Designer to assist them in making informed decisions on the implications of the choices they make in specifying materials and manufacturing processes for their designs in terms of carbon impact. Unfortunately some can be misleading, indicating for example that a particular material has a low potential environmental impact, but failing to inform on the reality of the economic viability in its use or how readily available it might be for that use. These tools also have their limits, for example few can cater for the huge variety of company type and address the varied environmental interests of their owners (or lack of it).
There is a need for designers to be fully aware of the broader issues relating to the environmental impact of their work beyond those that can be evaluated by a tool; highlighting the need for the complex range of issues associated with reducing environmental impact to be addressed along with and as creatively as all other design parameters.
This paper takes as a case study, the design of a digital cordless phone undertaken by the author for a major UK telecoms service provider, where a holistic approach to sustainability from the designer’s perspective was a fundamental project requirement and uses this as an example of how designers can set their own holistic approach to sustainability in New Product Development (NPD), placing ecotools in perspective and hopefully providing an inspirational example for student designers
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Interest in the commercial? Using commercial design projects in pedagogy
This paper considers the issues surrounding the use of live commercial design research projects as teaching material for Product Design students. The premise for the paper is based around the Design Unit, a design and research group at De Montfort University in Leicester, staffed by academics who are also involved in lecturing product design students. It highlights an observation that students may not become highly engaged when presented with assignments based on 'real life' design projects that have previously been completed by Design Unit staff. It could be argued that such projects are simply too big, the detail can seem esoteric and feel irrelevant to the fledgling designer. In addition, the commercial constraints of the real world project could, at times, impose inappropriate restrictions on student designers. As a lecturer used to dealing with industry experts and then being expected to present to design students on a project within a new industry sector, it could be quite easy to become complacent with regards to the student's prior knowledge. The aims of this paper are to explore what key areas can be extracted from commercial projects to make the best use of them as educational material. It will aim to suggest tools that could be used to present the material in an effective way and how this could better engage the student to help them understand the validity of the proposed design project or teaching aid
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