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
It is not always about gains: utilities and disutilities associated with treatment features in patients with moderate-to-severe psoriasis
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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
Influence of ion irradiation on switching field and switching field distribution in arrays of Co/Pd-based bit pattern media
International audienceWe have used ion irradiation to tune switching field and switching field distribution ͑SFD͒ in polycrystalline Co/Pd multilayer-based bit pattern media. Light He + ion irradiation strongly decreases perpendicular magnetic anisotropy amplitude due to Co/Pd interface intermixing, while the granular structure, i.e., the crystalline anisotropy, remains unchanged. In dot arrays, the anisotropy reduction leads to a decrease in coercivity ͑H C ͒ but also to a strong broadening of the normalized SFD/ H C ͑in percentage͒, since the relative impact of misaligned grains is enhanced. Our experiment thus confirms the major role of misorientated grains in SFD of nanodevice arrays. Today a major research effort in magnetism is targeted toward achieving ultrahigh density data storage with nano-scale magnets. Spin-transfer magnetic random access memory ͑spin-RAM͒ and bit patterned media ͑BPM͒ technologies are currently part of the most promising media. The implementation of both of these technologies relies on achieving in-detail physical understanding and control of the magnetization reversal mechanism in each nanoscopic individual bit to ensure reproducibility of the bit properties in order to avoid write errors. Perpendicular magnetic anisotropy ͑PMA͒ materials, such as polycrystalline Co/Pd, Co/Pt, and Co/Ni multilayers, are believed to be promising materials for both spin-RAM and BPM applications. 1–4 Indeed, they have a well defined high amplitude uniaxial anisotropy that provides good thermal stability while offering low critical current in spin-transfer devices 2 and tunable switching fields in BPM.
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