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81.
The time spent in dependence and the type of care an elderly receives are the two main cost drivers of long-term care (LTC). We aim to provide a better understanding of the duration of care by using a comprehensive social insurance dataset covering the LTC needs in Switzerland over a 20-years-period and including 230 000 observations on dependent elderly. First, using the framework of survival analysis, we calculate Kaplan–Meier estimates for the care duration and derive the main explaining factors through econometric models when care is received at home and in an institution. Retaining only significant covariates, the final accelerated failure time models allow us to predict the duration for different profiles of elderly along their age, gender, region of residence, type of household composition, acuity level and pre-retirement income. Second, we study the interaction of care durations when care is provided at home and in an institution. While our data supports that for short at-home care durations the time spent in institutional care is reduced, we find that both types of care are non-substitutes when the time spent at home has been longer. Under the latter regime, the time spent in institutional care remains at a constant level. Finally, given the longevity improvements over the period of observation, we analyze the impact of living longer on the time spent in dependence. Our results show that while the mean age at entry in dependence grows, the overall care duration does not significantly change. Given the expected increasing number of elderly in most developed countries, our study is relevant for government planning, budgeting social insurance schemes, estimating personal savings needs and calculating private insurance premiums. 相似文献
82.
《Biomedical chromatography : BMC》2017,31(12)
A sensitive LC–MS method was developed for the quantification of morusin in rat plasma using praeruptorin C as internal standard. After extraction with diethyl ether, post‐treatment samples were chromatographed on a Hypersil C18 column. An isocratic mobile phase consisting of methanol–water (70:30, v /v) was applied at a flow rate of 0.4 mL/min. Detection was performed via electrospray ionization source with positive ion mode using selected ion monitoring mode at m/z 443.1 for morusin and m/z 451.0 for IS. Acceptable linearity (r 2 ≥ 0.99) was observed over the concentration range of 1.5–800 ng/mL. This method was successfully applied in the pharmacokinetics study of morusin in rats. 相似文献
83.
《Biomedical chromatography : BMC》2017,31(12)
A sensitive and specific LC–MS/MS assay for determination of β ‐eudesmol in rat plasma was developed and validated. After liquid–liquid extraction with ethyl ether , the analyte and IS were separated on a Capcell Pak C18 column (50 × 2.0 mm, 5 μm) by isocratic elution with acetonitrile—water–formic acid (77.5:22.5:0.1, v /v/v) as the mobile phase at a flow rate of 0.4 mL/min. An ESI source was applied and operated in positive ion mode; a selected reaction monitoring scan was used for quantification by monitoring the precursor–product ion transitions of m/z 245.1 → 163.1 for β ‐eudesmol and m/z 273.4 → 81.2 for IS. Good linearity was observed in the concentration range of 3–900 ng/mL for β ‐eudesmol in rat plasma. Intra‐ and inter‐day precision and accuracy were both within ±14.3%. This method was applied for pharmacokinetic studies after intravenous bolus of 2.0 mg/kg or intragastric administration of 50 mg/kg β ‐eudesmol in rats. 相似文献
84.
The Toroid type high-pressure device and its predecessor, the Chechevitsa (lentil) type high-pressure device, are known to be used efficiently for the synthesis of new materials in recent decades. It was through the Chechevitsa device the first ultradense modification of silica, ‘stishovite’, was obtained. Both devices were essential for the industrial production of superhard materials in the USSR and other socialist countries. In 1980s, almost half of the world synthetic diamond and c-BN products were manufactured by these devices. However, the application of the Toroid device for examining the structure and physical properties of highly compressed substances has been considerably less appreciated. Meanwhile, the device has some unique features that have made possible 35-years of an extensive investigation of physical properties of substances at pressures up to 150 kbar, including electron transport and thermodynamic properties, elastic characteristics, viscosity, thermo-conductivity and other physical properties. Also, the device has been widely employed for structural X-ray and neutron diffraction studies of many materials. But it is not until recently that the convenience of the Toroid device for physical studies has been fully recognized. Through this recognition, the Toroid type device is today becoming increasingly popular among the researchers in the field of high pressures around the world. 相似文献
85.
S. Chandrasekaran K. Gopal P. X. Franklin Balasubramanian Jaganatha Sivakumar Gajendra Singh Shridhar Narayanan B. Gopalan Ansar A. Khan 《Biomedical chromatography : BMC》2013,27(8):1018-1026
The present investigation describes the development and validation of a sensitive liquid chromatography–mass spectrometry/mass spectrometry (LC‐MS/MS) method for the estimation of dorsomorphin in rat plasma. A sensitive LC‐MS/MS method was developed using multiple reaction monitoring mode, with the transition of m/z (Q1/Q3) 400.2/289.3 for dorsomorphin and m/z (Q1/Q3) 306.2/236.3 for zaleplon. Chromatographic separation was achieved on a reverse phase Agilent XDB C18 column (100 × 4.6 mm, 5 µm). The mobile phase consisted of acetonitrile and 5 mm ammonium acetate buffer (pH 6.0) 90:10 v/v, at a flow rate of 0.8 mL/min. The effluence was ionized in positive ion mode by electrospray ionization (ESI) and quantitated by mass spectrometry. The retention times of dorsomorphin and internal standard were found to be 2.13 and 1.13 min, respectively. Mean extraction recovery of dorsomorphin and internal standard in rat plasma was above 80%. Dorsomorphin calibration curve in rat plasma was linear (r2 ≥ 0.99) ranging from 0.005 to 10 µg/mL. Inter‐day and intra‐day precision and accuracy were found to be within 85–115% (coefficient of variation). This method was successfully applied for evaluation of the oral pharmacokinetic profile of dorsomorphin in male Wistar rats. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
86.
Shefali Saxena M. Palit Purnanand S. K. Raza 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):247-253
Abstract A series of structurally related unsymmetrically substituted methylphosphonate diesters have been synthesised and subjected to electron impact (El) mass spectral studies. These studies though aimed at total identification of the compounds, resulted in certain interesting observations and hence are being reported. In order to confirm the observations under electron impact and to support the mechanism of fragmentation we have also performed MSNS experiments in both daughter ion and parent ion modes. 相似文献
87.
Andrii Lozynskyi Borys Zimenkovsky Iryna Ivasechko Julia Senkiv Andrzej Gzella Olexandr Karpenko 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1149-1157
AbstractThe synthesis and anticancer activity evaluation of new thiazolo[4,5-b]pyridine-5-carboxylic acid amides is described. The structures of the synthesized compounds were confirmed by spectroscopic data and a single crystal X-ray diffraction analysis for 2.4. The synthesized compounds were screened for their in vitro anticancer activity according to US NCI protocols. The most active 7-(4-fluorophenyl)-2-oxo-2,3-dihydrothiazolo[4,5-b]pyridine-5-carboxylic acid (4-chlorophenyl)amide 2.2 and 7-(4-chlorophenyl)-2-oxo-2,3-dihydrothiazolo[4,5-b]pyridine-5-carboxylic acid (4-chlorophenyl)amide 2.5 were screened for their cytotoxicity effects on C6 Rat glioma cells and U373 Human glioblastoma astrocytoma cells which revealed promising results comparable to temozolamide as reference control according MTT assay data. 相似文献
88.
Both emission and excitation spectra of phosphorescence and delayed fluorescence of pyrene single crystals have been investigated between 2 K and 300 K using cw dye laser excitation. The experiments prove that the lowest triplet state is excitonic in nature in the high and low temperature crystalline phases. No evidence for triplet excimer emission could be found. The so-called regular broad band triplet excimer emission was spectrally resolved at low temperature and identified as trap emission. On the basis of polarized high resolution excitation spectra of undoped normal and perdeuterated pyrene (supplemented by Zeeman spectra at helium temperature) and the concentration dependent phosphorescence excitation spectra of isotopically mixed crystals the triplet state symmetry and the excitonic Davydov splitting of the low temperature crystalline phase was determined. The resonance pair interaction between the dimer molecules was found to be an order of magnitude smaller than predicted from calculations reported so far. 相似文献
89.
Superbase‐catalyzed domino 3H‐pyrroles synthesis from ketoximes and acetylene: DFT study vs experiment 下载免费PDF全文
Elimination of vinyl alcohol from 5‐vinyloxypyrrolines in the presence of superbases (final step of domino 3H‐pyrroles synthesis from ketoximes and acetylene) is studied computationally at different levels of theory in DMSO solution (PCM). The sequences of transformations starting from nucleophilic addition of hydroxide ion to carbon‐carbon or carbon‐nitrogen double bonds are proposed as possible mechanisms. Unusual reactivity of 2,5‐dimethylphenyl substituted 5‐vinyloxypyrroline is explained within these mechanisms. 相似文献
90.
Fred U. Nnamdi Dr. Colin Diner Prof. Pier Alexandre Champagne Prof. Michael G. Organ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(11):3855-3860
Two similar tridentate directing groups derived from glycine and 8-aminoquinoline were shown to enable the palladium-catalyzed anti-Markovnikov hydrofunctionalization of 4-pentenylamine with drastically different efficiencies. A computational investigation into the origin of the reactivity difference between these isomeric, carbonyl-transposed auxiliaries suggests that protonation state, thus charge of the substrate-metal complex prior to nucleopalladation is key. These investigations have culminated in a directing group design that can undergo Pd-catalyzed hydrofunctionalization under relatively mild conditions, as low as room temperature. 相似文献