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The proportion of the population over age 65 years is steadily increasing in Canada and the elderly who are unable to live independently are frequently institutionalized in chronic care facilities. We report our observations on movement disorders (MD) in an institutionalized elderly population of Saskatchewan. A representative sample of 67 subjects aged > or = 65 years had a detailed neurological evaluation on three separate occasions. MD were detected in 13 (19%) cases. The majority, 11 (16%), were females. Seven (10%) had essential tremor, 4 (6%) Parkinson's disease and 2 (3%) had drug-induced parkinsonism.  相似文献   
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A laboratory scale spray dryer was used to encapsulate vildagliptin (VLG), an antihyperglycemic drug, into different polymers such as poly(dl-lactide) (PDLA), poly(dl-lactide-glycolide)-50:50 (PLGA 50:50), and poly(dl-lactide-glycolide)-75:25 (PLGA 75:25). Response surface methodology (RSM) was employed to evaluate the effects of process and formulation factors on the encapsulation efficiency (EE). The physicochemical properties of the drug-loaded micro-/nanoparticles, mainly the drug loading (DL), particle size distribution, surface morphology, drug–polymer compatibility, and release rate were investigated. % EE of drug-loaded micro-/nanoparticles were in the range of 57.10% to 76.44%. PLGA50:50 micro-/nanoparticles showed highest EE as compared to PDLA and PLGA75:25 micro-/nanoparticles. The mean particle size of the micro-/nanoparticles containing PLGA 50:50, PLGA 75:25, and PDLA polymers were 428?nm, 640?nm, and 1.22 µm, respectively. Surface morphology study revealed smooth, spherical and nonporous surface structures of the micro-/nanoparticles. Fourier transform infrared spectroscopy studies confirmed the drug–polymer compatibility. Powder X-ray diffraction analysis of micro-/nanoparticles revealed that VLG was present in the amorphous form within the micro-/nanoparticles formulations. In vitro release study demonstrated that VLG is slowly released from micro-/nanoparticles for 12?h and the drug release rate was influenced by type and viscosity of polymers used. This work suggests that PDLA, PLGA 50:50, and PLGA75:25 polymers are able to sustain the VLG release rates from micro-/nanoparticles.  相似文献   
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Multimedia Tools and Applications - Current trend toward cloud computing coupled with emerging technologies such as high definition images/videos and 360-degree videos, has led the requirement of...  相似文献   
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Buoyancy forces result from the cooling or heating of a continuous stretching sheet, which causes a change in the resulting flow and thermal fields, and hence the heat transfer behavior in the manufacturing process. The study of the thermal buoyancy induced in boundary layer flow is important due to its recent advances in the areas of nuclear energy, electronics, and space technology. In this perspective, the aim of the present study is to investigate the effect of the buoyancy parameter on the magnetohydrodynamics boundary layer flow over an exponentially stretched sheet in the presence of nonlinear thermal radiation and porous media. Using similarity transformation, the flow model of partial differential equations is transformed into a set of coupled nonlinear ordinary differential equations. The efficient fourth‐order Runge‐Kutta scheme with the shooting method is used to solve the reduced equations. The impact of various associated parameters on velocity and temperature profiles were analyzed and computed through graphs. The major outcome of the present study shows the enhancement in the velocity distribution with the increase in the buoyancy parameter. Also, the increase in thermal buoyancy and thermal radiation leads to an increase in fluid temperature. Moreover, it is worth to note that the fluid velocity declines with the augmentation of the magnetic parameter.  相似文献   
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Novel two pack polyurethane wood finished coatings are prepared from renewable sources, such as vegetable oil based fatty acid and dimer fatty acid. In actual experimental part oleic acid was reacted with diethanolamine to obtain amide which was on condensation polymerization with dimer fatty acid converted into the polyesteramide polyol. These are all being used to prepare polyurethanes. The functional and structural elucidation of dimer fatty acid based polyesteramide and diethanolamide were carried out by end group analysis, spectral studies such as FTIR and 1H NMR. Average molar masses of the polyesteramide were estimated by gel permeation chromatography (GPC). The polyesteramide was used in the preparation of wood finished polyurethane coatings by reacting it with aromatic diisocyanates. Thermogravimetric analysis (TGA) was used to study the thermal behavior of coatings. Physico-chemical and coating properties of the coatings were investigated by using standard methods. The results indicated that the bio-based wood finished PU coatings provided good mechanical, weather resistance as well possessed adequate coating properties for wood surface protections.  相似文献   
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BACKGROUND: Generally the fabrication of polymeric membranes is a complicated and expensive process since it involves several steps. The preliminary preparation steps involve polymer drying and dissolution and is very time consuming and expensive. Currently, conventional electrothermal heating (CEH) is used to dissolve polyethersulfone in an aprotic solvent for membrane fabrication. Usually CEH requires 6 to 8 h at temperatures of 80 to 95 °C. This paper reports the fabrication and characterization of polyethersulfone (PES) asymmetric ultrafiltration membrane made from microwave (MW) synthesis casting solution consisting of various compositions of double solvents and lithium bromide (LiBr) additive. RESULTS: Homogeneous dual solvent dope solutions prepared via microware irradiation took only 1 h instead of the 7 h when prepared using CEH. The results also revealed that the membrane permeation and rejection rates, pore size and porosity were dependent on the ratio of LiBr to acetone. Membranes with LiBr kept at 2 and 3 wt% exhibited both high rejection and permeation rates with minimum pore sizes of 1.067 and 1.214 nm respectively. The presence of LiBr and the occurrence of chain scission were elucidated using Fourier transform infrared (FTIR) spectroscopy while its hydrophilic property was confirmed by water absorption and contact angle measurements. CONCLUSIONS: It was concluded that the microwave technique is capable of producing 1 L membrane solutions in less than 1 h. The membranes prepared from the microwave solutions show good rejection and permeation rates. Copyright © 2011 Society of Chemical Industry  相似文献   
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Effect of residual stress generated during tube fabrication, roll expansion and machining of stainless steel on the stress corrosion cracking (SCC) susceptibility was studied by testing fabricated tubes, tube–tube sheet joint and heavily machined plate of austenitic stainless steel (SS) in boiling MgCl2. U bend samples of machined plate were exposed to acidified SO4 + Cl? environment at room temperature to study its ambient temperature SCC behavior. The results correlate the SCC behavior of the SS tubes and roll expanded joints to the nature and magnitude of residual stresses present. The study also highlights the distinct difference in ambient temperature SCC behavior of machined vs. nonmachined surfaces.  相似文献   
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