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41.
Two studies examined the associations between life regrets and indicators of quality of life across the adult life span. Given that opportunities to undo regrets decline with age, regret intensity was expected to be inversely associated with subjective well-being and health among older adults. In addition, the research explored protective factors that have the potential to reduce older adults' regret intensity. It was suggested that being disengaged from undoing the consequences of regrets and having many future goals available may reduce older adults' intensity of regret and thereby contribute to a better quality of life. Across both studies, the findings demonstrate that older adults perceived reduced opportunities to undo the consequences of their regrets and that regret intensity predicted a reduced quality of life only among older adults. Furthermore, the findings support the adaptive value of disengagement and available future goals for managing life regrets in older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
Antonio Brogi Jean-Marie Jacquet Isabelle Linden 《Electronic Notes in Theoretical Computer Science》2003,68(3):284
The paper proposes a theoretical study of a coordination language embodying Linda's asynchronous communication primitive with a refined matching mechanism based on pairs composed of attribute names associated with their values. Computations in this language are described by means of an operational semantics, reporting the whole traces of executions. The non-compositionality of this intuitive operational semantics motivates the design of a compositional and fully abstract denotational semantics, which is then exploited for studying program equivalence in this setting. 相似文献
43.
Issa M. El-Nahhal Shehata M. Zourab Fawzi S. Kodeh Abdelraouf A. Elmanama Mohamed Selmane Isabelle Genois Florence Babonneau 《Journal of Materials Science: Materials in Electronics》2013,24(10):3970-3975
Zinc oxide nanoparticles were prepared and subsequently deposited onto the surface of the cotton fiber by ultrasonic irradiation. The optical, structure and morphology of the coated and un-coated cotton were examined by UV, fourier transform infrared spectroscopy, X-ray diffraction analysis (XRD) and scanning electron microscope (SEM)/Energy Dispersive X-ray analysis. XRD analysis revealed the presence of the crystalline metal oxide of hexagonal phase with an average crystallite size of 12 nm. These nanoparticles are probably physically adsorbed onto the cotton fiber surface. SEM analysis showed a distribution of ZnO nanorod assemblies of various diameters and lengths physically adsorbed onto the cotton fiber surface may take place. The ZnO-cotton fiber nano-composite were tested against Escherichia coli (gram negative) and Staphylococcus aureus (gram positive) cultures, and showed a significant antimicrobial activity. 相似文献
44.
The drive shaft in the propulsion system of a boat broke, while the vessel was sailing along the Western Canadian coast. This
part was made from a low-alloy steel grade 4340 quenched and tempered. Fractographic investigation at macro scale revealed
that the shaft failed under low rotating-bending variable stress. Fatigue propagation occurred on about 95% of the total cross
section of the shaft, under both low-cycle and high-cycle fatigue mechanisms. It was found that the fillet radius present
at the fracture’s origin was smaller than the one provisioned by design. This situation has raised the stress level at this
location higher than the one taken into consideration at the moment of the design calculations and caused the initiation of
the cracking. Moreover, although the shaft has been quenched and tempered, its actual hardness did not have the optimal value
for long-life fatigue strength. 相似文献
45.
Isabelle Marie-Joseph Laurent Linguet Marie-Line Gobinddass 《International journal of remote sensing》2013,34(8):3012-3027
Measurements of daily means of surface solar irradiance made at four ground stations in French Guiana are compared to estimates from the HelioClim-3 database produced by the Heliosat-2 method applied to Meteosat satellite images. The bias ranges from 12 W m?2 (6% of the mean of measurements) to 23 W m?2 (12%), depending on the stations. The root mean square difference ranges between 23 W m?2 (11%) and 35 W m?2 (18%). The correlation coefficient (r) is close to 0.9. Better results are observed during the rainy season than during the dry season. Uncertainties are mainly due to the presence of clouds, large viewing angles of the Meteosat satellite, and limitations of the atmospheric transmittance model under the tropical atmospheric conditions. It is concluded that the Heliosat-2 method provides new knowledge about solar radiation in French Guiana. 相似文献
46.
Chitosan (CS) has received much attention as a functional biopolymer for designing various hydrogels for biomedical applications. This review provides an overview of the different types of CS‐based hydrogels, the approaches that can be used to fabricate hydrogel matrices with specific features and their applications in controlled drug delivery and tissue engineering. Emphasis is laid on the recent design concepts of hybrid hydrogels based on mixtures of CS and natural or synthetic polymers, interpenetrating polymer networks as well as composite hydrogels prepared by embedding nanoparticles into CS matrices. © 2017 Society of Chemical Industry 相似文献
47.
Huriye Akdas-Kilig Jean-Pierre MalvalFabrice Morlet-Savary Anu SinghLoic Toupet Isabelle Ledoux-RakJoseph Zyss Hubert Le Bozec 《Dyes and Pigments》2012,92(1):681-688
Two new 4,4′-bis(donor)-6,6′-diphenyl- 2,2′-bipyridine ligands and their corresponding D2d (CuI, AgI, ZnII) octupolar metal complexes were synthesized, and their linear and nonlinear optical properties were investigated. A single crystal X-ray structure was also determined for the bis[4,4′-bis(diethylaminostyryl)-6,6′-diphenyl-bipyridine]copper(I) complex, which revealed a distorded pseudo-tetrahedral geometry. Molecular second-order nonlinear optical properties were determined for the complexes using the Harmonic Light Scatterring technique at 1.91 μm. These metallo-chromophores display large first hyperpolarizabilities β1.91 in the range of 211-340 × 10−30 esu, which increase with the Lewis acidity of the metal ion. The two-photon absorption properties of the bipyridyl ligands and related complexes were determined using either the two-photon emission method for fluorescent compounds or the open aperture Z-scan technique for non emissive ones. The complexes display red-shifted two-photon absorption bands compared to their metal-ion free chromophores, as well as a large increase of the maximum two-photon absorption cross-sections. 相似文献
48.
Isabelle Moretti Alain Prinzhofer João Françolin Cleuton Pacheco Maria Rosanne Fabian Rupin Jan Mertens 《International Journal of Hydrogen Energy》2021,46(5):3615-3628
In many basins, hydrogen-emitting structures are now observed, but the estimation of the H2 flow leading to their formation remains poorly constrained since all data show that the H2 emissions are variable in space and time. We present here the data of a long-term monitoring campaign with a high density of permanent hydrogen detectors installed in 2 structures in the Minas Gerais State (Brazil). Results show that two kinds of signals are recorded, large sporadic pulses that affect the H2 content of the soil for one or two days and smaller ones, with a daily periodicity, that last 6 h and during which the near surface soil concentration usually does not exceed 200 ppm. This last signal is very regular in frequency, less in amount, and the daily maximum happens around noon or in the early afternoon. We interpret the large pulses as evidences of a deep hydrogen flux, leaking either from a reservoir located in the subsurface, from an aquifer which is degassing or, although it seems unlikely, directly from the H2 generation area.The time correlation between the pulse and the increase of the daily signal suggests that this last one corresponds to the slow release of the gas that has been captured by the soil during its transport towards the surface. This daily signal is most likely influenced by external factors such as atmospheric pressure and sub-surface bacterial activity. In map view, the lack of correlation between the highest hydrogen concentrations over time suggests that the soil is very heterogeneous and that preferential pathways exist. The results confirm that long-term monitoring, over a few months, is mandatory to catch a certain number of high pulses and so to have a better estimation of the real flow. Data also suggests that sensors with a large concentration range should be used (from 10 to several 104 ppm). Even if quantification of leakage doesn't help to quantify the subsurface reserves, these new data allow a more precise evaluation of the quantity of H2 released in surface by these structures, few hundred of kilo per day, and confirm the high H2 prospectivity of this basin. 相似文献
49.
Markus Fröbel Ajay Perumal Tobias Schwab Malte C. Gather Björn Lüssem Karl Leo 《Organic Electronics》2013,14(3):809-813
We report efficient and bright organic light-emitting devices operated by capacitive energy coupling. In this approach, the organic layers are enclosed between sputter-deposited hafnium dioxide layers to prevent charge carrier injection. When a sinusoidal voltage signal is applied to the electrodes, the devices emit bright green light whereas no detectable emission is generated upon application of a constant voltage. The efficiency of the process depends heavily on the frequency of the applied voltage signal. By optimizing the driving scheme, a record luminous efficacy for AC driven OLEDs of 2.7 lm/W at 500 cd/m2 is achieved. 相似文献
50.
Isabelle Roche-Cerasi Torbjørn Rundmo Johannes Foss Sigurdson Dagfinn Moe 《Accident; analysis and prevention》2013
The main aim of the present study was to compare risk perception among Norwegians (n = 512) living in the region of Oslo. This study was part of an ERANET 13 project entitled PETRIS, Perception of transport risk in France and Norway. The data collection was carried out in January 2011. The response rate was 51 percent. The results showed that respondents, divided in two groups according to their transport mode preferences, assessed differently risk perception in public and private transportation. Respondents who preferred collective transportation assessed the probability of experiencing criminality in collective transport modes as higher than those who preferred private modes. They were also more worried of experiencing accidents, criminality, and terror attacks in collective transportation. The relationship between transport mode preferences and use, risk perception and worry are discussed. 相似文献