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OBJECTIVE: To evaluate what nursing home medical directors actually do, what they and other nursing home personnel believe would be desirable to do, and what problems and deficiencies are perceived. DESIGN: Mail survey with follow-up telephone interview when necessary. SETTING: Forty-five nursing facilities in upstate New York. PARTICIPANTS: The medical directors, administrators, and directors of nursing of the 45 facilities. MEASUREMENTS: Inventory of what medical directors reported as to their actual activities and time spent, and of what they, the administrators, and the directors of nursing felt should be their responsibilities and activities under ideal circumstances. RESULTS: For part-time medical directors, self-reported time spent on medical directorship activities averaged 12 hours per month; of all directors, 45% spent 8 hours or less per month. Proportion of time spent on various specific activities varied widely. There was general agreement that substantially more time should be spent, in particular, on evaluating and addressing problems of adequacy and quality of care, communicating with attending physicians about problems, and assisting with inservice training programs. CONCLUSIONS: To fill the role adequately, more time should be spent by many part-time medical directors, which will require greater financial commitment by facilities and reimbursement systems. Efforts need to made to better coordinate the expectations of medical directors and facility staff.  相似文献   
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Self-assembly of artificial peptides has been widely studied for constructing nanostructured materials, with numerous potential applications in the nanobiotechnology field. Herein, we report the synthesis and hierarchical self-assembly of collagen-mimetic peptides (CMPs) bearing various aromatic groups at the N-termini, including 2-naphthyl, 1-naphtyl, anthracenyl, and pyrenyl groups, into nanofibers. The CMPs (R-(GPO)n: n > 4) formed a triple helix structure in water at 4 °C, as confirmed via CD analyses, and their conformations were more stable with increasing hydrophobicity of the terminal aromatic group and peptide chain length. The resulting pre-organized triple helical CMPs showed diverse self-assembly into highly ordered nanofibers, reflecting their slight differences in hydrophobic/hydrophilic balance and configuration of aromatic templates. TEM analysis demonstrated that 2Np-CMPn (n = 6 and 7) and Py-CMP6 provided well-developed natural collagen-like nanofibers and An-CMPn (n = 5–7) self-assembled into rod-like micelle fibers. On the other hand, 2Np-CMP5 and 1Np-CMP6 were unable to form nanofibers under the same conditions. Furthermore, the Py-CMP6 nanofiber was found to encapsulate a guest hydrophobic molecule, Nile red, and exhibited unique emission behavior based on the specific nanostructure. In addition to the ability of CMPs to bind small molecules, their controlled self-assembly enables their versatile utilization in drug delivery and wavelength-conversion nanomaterials.  相似文献   
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Summary An oligomer of the methyl acrylate unsaturated trimer bearing 2-carbomethoxy-2-propenyl ω-end group (M n = 1300, M w/M n = 1.7, and functionality > 0.7) was copolymerized as a macromonomer (0.02 mol/L) with styrene (1.0 mol/L) in benzene at 60 °C. The amounts of monomer and macromonomer in the feed simultaneously decreased with increasing time to indicate copolymer formation, and the macromonomer was found to be as reactive as styrene toward poly(styrene) radicals. The M ns of the copolymers were 13900–22000 depending on conversion. No resonance due to the unsaturated <ω-end group bound to the poly(styrene) chain was detected by 1H-NMR spectroscopy, indicating that no fragmentation of adduct radical of the end group to expel the poly(methyl acrylate trimer) radical. Polymerization of ethyl methacrylate (1.0 mol/L) in the presence of the macromonomer (0.02 mol/L) resulted in a mixture of the unreacted macromonomer and homopolymer of ethyl methacrylate. No end group bound to the poly(ethyl methacrylate) was detected by 1H-NMR spectroscopy, excluding the possibility of addition fragmentation chain transfer to the macromonomer to expel an oligomer radical of the methyl acrylate trimer. Addition of the poly(methacrylate) radical to the macromonomer is extremely slow under the present conditions of copolymerization. Received: 27 March 2003/Revised version: 30 April 2003/ Accepted: 30 April 2003 Correspondence to Bunichiro Yamada  相似文献   
4.
The microphase separation structure in the molten state and the structure formation in crystallization from such ordered melt were investigated for the blends of polystyrene–polyethylene block copolymers (SE) with polystyrene homopolymer (PS) and polyethylene homopolymer (PE) and for the blends consisting of two kinds of SE with different copolymer compositions from each other, using synchrotron small-angle X-ray scattering techniques (SAXS). The copolymer compositions of SE block copolymers employed were 0.34, 0.58 and 0.73 wt. fraction of PE, and their melt morphologies were cylindrical, lamellar and lamellar, respectively. Macrophase separation or the morphology change in the melt occurred depending on the molecular weight and the blend composition, as reported so far. In crystallization from such macrophase-separated and microphase-separated melts, the melt morphology was completely kept for all the blends. Crystallization behavior was also investigated for the blends. The crystallization within the spherical and cylindrical domains surrounded by glassy PS was not observed for SE/PS blends. In the crystallization from the macrophase-separated melt, two exothermal peaks were observed in the DSC measurements, while a single peak was observed for other blends. For the blends with PS, the degree of crystallinity was depressed and the apparent activation energy of crystallization was high, compared to those for the corresponding neat SE. For SE/PE and SE/SE blends, those were changed depending on the blend composition.  相似文献   
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We propose a stable and efficient particle‐based method for simulating highly viscous fluids that can generate coiling and buckling phenomena and handle variable viscosity. In contrast to previous methods that use explicit integration, our method uses an implicit formulation to improve the robustness of viscosity integration, therefore enabling use of larger time steps and higher viscosities. We use Smoothed Particle Hydrodynamics to solve the full form of viscosity, constructing a sparse linear system with a symmetric positive definite matrix, while exploiting the variational principle that automatically enforces the boundary condition on free surfaces. We also propose a new method for extracting coefficients of the matrix contributed by second‐ring neighbor particles to efficiently solve the linear system using a conjugate gradient solver. Several examples demonstrate the robustness and efficiency of our implicit formulation over previous methods and illustrate the versatility of our method.  相似文献   
7.
Abstract— The display used in current cell phones has an air gap between the cover glass and the liquid‐crystal‐display (LCD) module to prevent the LCD glass from being damaged. Reflections at the boundaries of the air gap cause a reduction in the LCD luminance and contrast. To address this problem, a newly proposed LCD structure has been investigated. The “Super View Resin (SVR),” a transparent elastic resin which improves the shock resistance and visibility of the LCD, has been developed. Filling the air gap between the cover glass and LCD module with a refractive‐index‐matching resin solves the light‐reflection problem inherent in the use of a reinforced cover‐glass lens. Moreover, the elastic filler works as a damper, reducing any external shock, which prevents not only the cover glass and LCD module from being damaged, but also the glass from being shattered when it is broken.  相似文献   
8.
We have investigated the relation between the crystal structure and superconductivity in La1.9Bi0.1CuO4+ , in which the phase separation observed in La2CuO4+ is suppressed. A phase diagram in theT– plane is given for La1.9Bi0.1CuO4+ with excess oxygen. For very small values, the crystal structure is orthorhombic, and an orthorhombic-tetragonal phase transition occurs markedly at 0.03 in the measured temperature range between 13 and 293 K. Superconductivity is observed in the range of 0.04<<0.11. This is clear evidence thathigh-T c superconductivity also appears in the tetragonal phase.  相似文献   
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