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排序方式: 共有200条查询结果,搜索用时 15 毫秒
1.
Virtanen Pekka; Rantalaiho Liisa; Koivisto Anna-Maija 《Canadian Metallurgical Quarterly》2003,8(2):123
Medical students entering the labor market were studied to find out whether the improvement of psychosocial well-being depends on characteristics of their careers. Psychosocial well-being was described on the basis of psychosomatic stress symptoms, psychological distress (General Health Questionnaire), and strain resistance resources (Sense of Coherence). The 3-year follow-up showed that among women the improvement of strain resistance resources was delayed in the group with several entries into work. Among men the findings suggested associations between stress symptoms and career characteristics. Most of the results, however, did not support the hypothesis about the division of the participants into those with a stable career and improving well-being and those with a fragmented career and low well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
P J?k?l? M Riekkinen M Bj?rklund E Koivisto B Schmidt P Riekkinen 《Canadian Metallurgical Quarterly》1996,318(2-3):239-250
The present study investigated if short-term treatment with an L-type Ca2+-channel inhibitor, nimodipine, can stimulate cognitive functioning and cortical electroencephalograph (EEG) arousal, and potentiate the effect of a cholinesterase inhibitor, metrifonate. Pretraining administration of nimodipine (3, 10 and 30 mg/kg, p.o.) had no effect on water maze and passive avoidance behavior of young neurologically intact controls, or water maze and passive avoidance performance failure induced by scopolamine pretreatment (i.p.; 0.4 mg/kg during the water maze and 2.0 mg/kg during the passive avoidance study), medial septal lesioning, or aging. Furthermore, nimodipine (3, 10 and 30 mg/kg, p.o.) had no effect on the improvement by metrifonate (10 mg/kg, p.o.) of the water maze and passive avoidance failure induced by scopolamine pretreatment or medial septal lesioning, nor did it affect the potential of metrifonate (30 mg/kg. p.o.) to improve the water maze or passive avoidance behavior of aged rats. Finally, nimodipine (3, 10 and 30 mg/kg, p.o.) had no effect on spontaneously occurring thalamically generated neocortical high-voltage spindles or spectral EEG activity of young controls, nor did it alleviate the spectral EEG abnormality induced by scopolamine (0.2 mg/kg, i.p.) administration. Also, the combination of nimodipine 3 or 10 mg/kg and a subthreshold dose of metrifonate 10 mg/kg could not suppress high-voltage spindles or scopolamine treatment-induced spectral EEG activity abnormalities. According to the present results, short-term treatment with nimodipine does not stimulate cognitive functions or increase cortical EEG arousal, and does not block or potentiate the propensity of metrifonate to improve cognitive performance of rats. 相似文献
3.
A grid (or a mesh) is a two-dimensional permutation: an m× n-grid of size mn is an m× n-matrix where the entries run through the elements {1,2, …, mn}. We prove that if δ1 and δ2 are any two linear orders on {1,2, …, N}, then they can be simultaneously embedded (in a well defined sense) into a unique grid having the smallest size. 相似文献
4.
Optical Properties of Self‐Assembled Cellulose Nanocrystals Films Suspended at Planar–Symmetrical Interfaces
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Blaise L. Tardy Mariko Ago Jiaqi Guo Maryam Borghei Tero Kämäräinen Orlando J. Rojas 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(47)
Hierarchically structured materials comprising rod‐like, chiral, nanoparticles are commonly encountered in nature as they can form assemblies with exceptional optical and mechanical characteristics. These include cellulose nanocrystals (CNCs), which have a large potential for the fabrication of bioinspired materials mimicking those advanced properties. Fine‐tuning the optomechanical properties of assemblies obtained from CNCs hinges on the transformations from suspensions of liquid crystals to long‐range order in the dry state. So far, associated transitions have been studied using trivial interfaces such as planar substrates. Such transitions are explored as they evolve onto meshed supports. The meshed substrate offers a complex topology, as is encountered in nature, for the formation of CNCs films. The CNCs self‐assembly occurs under confinement and support of the framework bounding the mesh openings. This leads to coexisting suspended and supported nanoparticle layers exhibiting nematic and/or chiral nematic order. Optical microscopy combined with crossed polarizers indicate that the formation of the suspended films occurs via intermediate gelation or kinetic arrest of CNCs across the mesh's open areas. The formation of self‐standing, ultrathin films of CNCs with tunable optical properties, such as selective reflections in the visible range (structural color), is demonstrated by using the presented simple and scalable approach. 相似文献
5.
Vesa Halava Tero Harju Tomi Kärki Patrice Séébold 《Theoretical computer science》2009,410(8-10):943-948
We prove that there exist infinitely many infinite overlap-free binary partial words containing at least one hole. Moreover, we show that these words cannot contain more than one hole and the only hole must occur either in the first or in the second position. We define that a partial word is -overlap-free if it does not contain a factor of the form where the length of is at least . We prove that there exist infinitely many 2-overlap-free binary partial words containing an infinite number of holes. 相似文献
6.
Tero Tulenheimo 《Journal of Logic, Language and Information》2009,18(4):559-591
The hybrid logic H(@,ˉ){\mathcal{H}(@,\downarrow)} and the independence friendly modal logic IFML are compared for their expressive powers. We introduce a logic IFML
c
having a non-standard syntax and a compositional semantics; in terms of this logic a syntactic fragment of IFML is singled out, denoted IFML
c
. (In the Appendix it is shown that the game-theoretic semantics of IFML
c
coincides with the compositional semantics of IFML
c
.) The hybrid logic H(@,ˉ){\mathcal{H}(@,\downarrow)} is proven to be strictly more expressive than IFML
c
. By contrast, H(@,ˉ){\mathcal{H}(@,\downarrow)} and the full IFML are shown to be incomparable for their expressive powers. Building on earlier research (Tulenheimo and Sevenster 2006), a
PSPACE-decidable fragment of the undecidable logic H(@,ˉ){\mathcal{H}(@,\downarrow)} is disclosed. This fragment is not translatable into the hybrid logic H(@){\mathcal{H}(@)} and has not been studied previously in connection with hybrid logics. In the Appendix IFML
c
is shown to lack the property of ‘quasi-positionality’ but proven to enjoy the weaker property of ‘bounded quasi-positionality’. The latter fact provides from the IFML internal perspective an account of what makes the compositional semantics of IFML
c
possible. 相似文献
7.
It is widely agreed that employee non-adherence to information security policies poses a major problem for organizations. Previous research has pointed to the potential of theories of moral reasoning to better understand this problem. However, we find no empirical studies that examine the influence of moral reasoning on compliance with information security policies. We address this research gap by proposing a theoretical model that explains non-compliance in terms of moral reasoning and values. The model integrates two well-known psychological theories: the Theory of Cognitive Moral Development by Kohlberg and the Theory of Motivational Types of Values by Schwartz. Our empirical findings largely support the proposed model and suggest implications for practice and research on how to improve information security policy compliance. 相似文献
8.
9.
Ari Seppälä Mamdouh El Haj Assad Tero Kapanen 《Structural and Multidisciplinary Optimization》2008,36(4):355-363
A suitable combination of materials for sheltering a system from a sudden change of environmental temperature has been theoretically
studied. The protective composite wall consists of two materials. An insulating material is placed on the outer surface, while,
for the inner surface, materials that have good heat storage properties but negligible heat transfer resistance are chosen.
The results show that by replacing some of the insulation material with a heat storage material, the temperature of the protected
system can be maintained at a considerably lower level. Although the optimal thickness ratio X depends on the Biot number, Fourier number, and on the heat capacity ratio K
C, for a large number of thermal protection cases, the approximation X = 0.45 yields practically the minimum progress of the transient. If the Biot number is sufficiently small, it is better to
replace all of the insulation material with a good heat storage material. 相似文献
10.
Vesa Halava Tero Harju Juhani Karhumki Michel Latteux 《Theoretical computer science》2007,380(3):355-362
In the Post Correspondence Problem (PCP) an instance (h,g) consists of two morphisms h and g, and the problem is to determine whether or not there exists a nonempty word w such that h(w)=g(w). Here we prove that the PCP is decidable for instances with unique blocks using the decidability of the marked PCP. Also, we show that it is decidable whether an instance satisfying the uniqueness condition for continuations has an infinite solution. These results establish a new and larger class of decidable instances of the PCP, including the class of marked instances. 相似文献