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31.
Vansteenkiste Maarten; Timmermans Tinneke; Lens Willy; Soenens Bart; Van den Broeck Anja 《Canadian Metallurgical Quarterly》2008,100(2):387
Previous work within self-determination theory has shown that experimentally framing a learning activity in terms of extrinsic rather than intrinsic goals results in poorer conceptual learning and performance, presumably because extrinsic goal framing detracts attention from the learning activity and is less directly satisfying of basic psychological needs. According to the match perspective, experimental extrinsic, compared to intrinsic, goal framing should enhance learning and performance for learners who personally hold a stronger extrinsic than intrinsic goal orientation, as these learners' personally held goals match with the situationally induced goals. An experimental field study among 5th-6th grade children shows that extrinsic goal framing resulted in poorer autonomous motivation, conceptual (but not rote) learning, and persistence compared to intrinsic goal framing, irrespective of participants' personal intrinsic versus extrinsic goal orientations and their spontaneous perception of the learning activity as serving an intrinsic or an extrinsic goal. The authors conclude that teachers can best promote intrinsic goals, even when facing students who personally hold a stronger extrinsic than intrinsic goal orientation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Dirkzwager Anja J. E.; Bramsen Inge; Adèr Herman; van der Ploeg Henk M. 《Canadian Metallurgical Quarterly》2005,19(2):217
This study examines secondary traumatization among 708 partners and 332 parents of Dutch peacekeepers (i.e., personnel who participated in military actions implemented by international organizations such as the United Nations). Partners or parents of peacekeepers with 4 levels of posttraumatic stress symptoms were compared on posttraumatic stress, health problems, the quality of the marital relationship, and social support. In comparison with partners of peacekeepers without posttraumatic stress disorder (PTSD) symptoms, partners of peacekeepers with PTSD symptoms reported more sleeping and somatic problems, reported more negative social support, and judged the marital relationship as less favorable. No significant differences were found for parents. Thus, peacekeepers' stress reactions were related to various problems of their partners. A systemic approach to the treatment of persons with PTSD appears appropriate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Morgenthaler M Schweizer E Hoffmann-Röder A Benini F Martin RE Jaeschke G Wagner B Fischer H Bendels S Zimmerli D Schneider J Diederich F Kansy M Müller K 《ChemMedChem》2007,2(8):1100-1115
This review describes simple and useful concepts for predicting and tuning the pK(a) values of basic amine centers, a crucial step in the optimization of physical and ADME properties of many lead structures in drug-discovery research. The article starts with a case study of tricyclic thrombin inhibitors featuring a tertiary amine center with pK(a) values that can be tuned over a wide range, from the usual value of around 10 to below 2 by (remote) neighboring functionalities commonly encountered in medicinal chemistry. Next, the changes in pK(a) of acyclic and cyclic amines upon substitution by fluorine, oxygen, nitrogen, and sulfur functionalities, as well as carbonyl and carboxyl derivatives are systematically analyzed, leading to the derivation of simple rules for pK(a) prediction. Electronic and stereoelectronic effects in cyclic amines are discussed, and the emerging computational methods for pK(a) predictions are briefly surveyed. The rules for tuning amine basicities should not only be of interest in drug-discovery research, but also to the development of new crop-protection agents, new amine ligands for organometallic complexes, and in particular, to the growing field of amine-based organocatalysis. 相似文献
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35.
Sandra Biedermann-Brem Maurus Biedermann Anja Fankhauser-Noti Koni Grob Rüdiger Helling 《European Food Research and Technology》2007,224(3):309-314
A simplified method is presented for determining epoxidized soy bean oil (ESBO) in food or food simulants, such as olive oil. ESBO is transesterified with methoxide/methanol directly in the homogenated food, i.e. without prior extraction, and analyzed on a cyanopropyl or phenyl polysiloxane stationary phase without formation of dioxolanes. For most foods, flame ionization detection (FID) was appropriate, but for samples with interfering components, GC–MS was needed. Chemical ionization (CI) with ammonia is more sensitive and more selective than electron impact ionization (EI). In CI, positive and negative ion monitoring (PCI and NCI) are similar in sensitivity, but different in selectivity, i.e. the combination of the two is well suited for confirmation. Results are shown to be in agreement with on-line LC–GC–FID. 相似文献
36.
Influence of light on food relevant fungi with emphasis on ochratoxin producing species 总被引:1,自引:0,他引:1
Schmidt-Heydt M Rüfer C Raupp F Bruchmann A Perrone G Geisen R 《International journal of food microbiology》2011,145(1):229-237
The influence of light of varying wavelength on growth and ochratoxin A biosynthesis of Aspergillus carbonarius, A. niger, A. steynii and on Penicillium nordicum and P. verrucosum was analysed. For comparison the influence of light on various other food relevant fungi, including citrinin producers, was also tested. Generally the Aspergilli seem to be more resistant to light treatment than the Penicillia. Interestingly wavelengths from both sides of the spectrum, e. g. red (long wavelength, 627 nm) and blue (short wavelength 470-455 nm) had the strongest inhibitory effects on growth and ochratoxin A biosynthesis. Blue light generally had a stronger effect. Light of moderate wavelength, 590 to 530 nm, (yellow to green) had more a positive than a negative influence on growth or ochratoxin A biosynthesis compared to the control (dark incubation). The light effect on growth and ochratoxin A biosynthesis was dependent on the growth medium. In contrast to malt extract medium (MEA), YES medium, as an especially nutrient rich medium, had an attenuating effect on the reactivity against light. However the tendency of the response in both media was the same. Moreover, the light intensity strongly influences how the fungus reacts. Depending on the intensity and the resistance of the species a complete cessation of growth and/or inhibition of ochratoxin A biosynthesis could be achieved. Light irradiation has the opposite effect on ochratoxin A than citrinin, two mycotoxins which can be produced simultaneously in P. verrucosum. Citrinin was produced essentially under light conditions which inhibited ochratoxin A biosynthesis. The same was true for a derivative of ochratoxin, in particular a derivative of ochratoxin β in A. carbonarius. A. carbonarius produced high amounts of the ochratoxin β derivative under blue light when the production of ochratoxin A was ceased at the most inhibiting conditions used (MEA, royal blue light, 455 nm, 1700 lx). Light has a growth stalling but not inactivating effect on aerial mycelia. If a non-growing colony under light is shifted to the dark it immediately grows normally. However on spores blue light has a deactivating effect. After incubation of spores of P. verrucosum for 24 h under blue light up to 97% of the spores were no longer able to germinate. Again the spores of the Aspergilli were much more resistant. 相似文献
37.
Paul Geoerg Florian Berchtold Steven Gwynne Karen Boyce Stefan Holl Anja Hofmann 《火与材料》2019,43(7):759-781
To quantify the evacuation process, evacuation practitioners use engineering egress data describing the occupant movement characteristics. These data are typically based to young and fit populations. However, the movement abilities of occupants who might be involved in evacuations are becoming more variable—with the building populations of today typically including increasing numbers of individuals: with impairments or who are otherwise elderly or generally less mobile. Thus, there will be an increasing proportion of building occupants with reduced ability to egress. For safe evacuation, there is therefore a need to provide valid engineering egress data considering pedestrians with disabilities. Gwynne and Boyce recently compiled a series of data sets related to the evacuation process to support practitioner activities in the chapter Engineering Data in the SFPE Handbook of Fire Protection Engineering. This paper supplements these data sets by providing information on and presenting data obtained from additional research related to the premovement and horizontal movement of participants with physical‐, cognitive‐, or age‐related disabilities. The aim is to provide an overview of currently available data sets related to, and key factors affecting the egress performance of, mixed ability populations which could be used to guide fire safety engineering decisions in the context of building design. 相似文献
38.
Identification of Correlative Shifts in Indices of Brain Cholesterol Metabolism in the C57BL6/Mecp2tm1.1Bird Mouse,a Model for Rett Syndrome 下载免费PDF全文
Dieter Lütjohann Adam M. Lopez Jen‐Chieh Chuang Anja Kerksiek Stephen D. Turley 《Lipids》2018,53(4):363-373
Rett syndrome (RS) is a pervasive neurodevelopmental disorder resulting from loss‐of‐function mutations in the X‐linked gene methyl‐Cpg‐binding protein 2 (MECP2). Using a well‐defined model for RS, the C57BL6/Mecp2tm1.1Bird mouse, we have previously found a moderate but persistently lower rate of cholesterol synthesis, measured in vivo, in the brains of Mecp2?/y mice, starting from about the third week after birth. There was no genotypic difference in the total cholesterol concentration throughout the brain at any age. This raised the question of whether the lower rate of cholesterol synthesis in the mutants was balanced by a fall in the rate at which cholesterol was converted via cholesterol 24‐hydroxylase (Cyp46A1) to 24S‐hydroxycholesterol (24S‐OHC), the principal route through which cholesterol is ordinarily removed from the brain. Here, we show that while there were no genotypic differences in the concentrations in plasma and liver of three cholesterol precursors (lanosterol, lathosterol, and desmosterol), two plant sterols (sitosterol and campesterol), and two oxysterols (27‐hydroxycholesterol [27‐OHC] and 24S‐OHC), the brains of the Mecp2 ?/y mice had significantly lower concentrations of all three cholesterol precursors, campesterol, and both oxysterols, with the level of 24S‐OHC being ~20% less than in their Mecp2 +/y controls. Together, these data suggest that coordinated regulation of cholesterol synthesis and catabolism in the central nervous system is maintained in this model for RS. Furthermore, we speculate that the adaptive changes in these two pathways conceivably resulted from a shift in the permeability of the blood–brain barrier as implied by the significantly lower campesterol and 27‐OHC concentrations in the brains of the Mecp2?/y mice. 相似文献
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40.
Anja S. GoldmannLeonie Barner Michael KauppAndrew P. Vogt Christopher Barner-Kowollik 《Progress in Polymer Science》2012,37(7):975-984
Modular ligation strategies for the functionalization of polymeric microspheres provide new perspectives for their applications in material science. In the current trend article we highlight variable synthetic procedures for generating functional microspheres via orthogonal modular conjugation chemistries. An overview of the different surface chemistries available is provided, followed by surface-sensitive characterization techniques relevant for the microparticles. Finally, we explore future trends in modular orthogonal modification approaches on microparticles and provide an outlook on the perspectives that the field of surface-modification of polymeric microparticles holds. 相似文献