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91.
Landscape issues are of interest in many disciplines, but they are seldom seen as an opportunity for inter- or transdisciplinary cooperation. This limits the ability to account for real world complexity. Bridging human and natural sciences intends to foster and coordinate communication about landscape-related issues—within academia and between science and society. The collection of papers in this special issue and the recommendations for future research are selected from the conference “Multifunctional Landscapes—Interdisciplinary Approaches to Landscape Research and Management” in Roskilde, Denmark, 2000. The contributions all bear evidence of an integrating approach to landscape research, bridging human and natural sciences.  相似文献   
92.
Over the past two decades, a significant number of studies in the United States, Canada and Europe have attempted to identify links between neighbourhood characteristics and antisocial behaviour of children and adolescents. Despite the abundance of work, the question of the choice of spatial scale has received little attention. Indeed, few studies have used different scales simultaneously in order to identify the most relevant scale. The aim of our study is precisely to identify the spatial scale in the most convincing explanation of antisocial behaviour violent and nonviolent in mid-adolescence and to better understand whether these are the characteristics of the immediate social environment at home or those of a much larger space that best explain the frequency of these behaviours. Using data from the a Montreal longitudinal study (ELEM) for 1037 boys from neighborhood socioeconomically disadvantaged, we tested the influence of different spatial scales defined from buffer zones (5, 10, 15, 20 and 30 minutes walk) from the residence of the child. The results show a significant relationship between low socioeconomic area and violent behaviour regardless of the spatial scale used. However, this relationship is significantly stronger for the smaller spatial units. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
93.
Plasmon resonance of gold nanoparticles is responsible of the electromagnetic (EM) Surface Enhanced Raman Scattering (SERS) effect. Interaction of an amorphous matrix with a SERS substrate was studied. Thin films with different thickness of amorphous TiO2 coated on a Klarite® substrate show a 100 times enhancement of the Raman signal. Distance dependence of the SERS interaction was shown to be less than 60 nm.  相似文献   
94.
Mixed and pure gels of gelatin and whey protein concentrate (WPC) were formed by using temperature and high pressure simultaneously. Combining these gel formation methods enables the two polymer networks to set at the same time. The microstructure of the gels was studied by means of light microscopy and transmission electron microscopy, and the rheological properties by means of dynamic oscillatory measurements and tensile tests. The pH values investigated were 5.4, 6.8 and 7.5. The isoelectric point of the WPC is around pH 5.2 and that of gelatin between pH 7.5 and 9. At pH 5.4, the mixed gel formed a phase-separated system, with a gelatin continuous network and spherical inclusions of the WPC. The storage modulus (G) of the mixed gel was similar to that of a pure gelatin gel. At pH6.8, the mixed gel formed a phase-separated system, composed of an aggregated network and a phase with fine strands. The aggregated network proved to be made up of both gelatin and WPC, and the fine strands were formed of gelatin. The mixed gel at pH 6.8 showed a high G compared with the pure gels, which decreased significantly when the gelatin phase melted. At pH 7.5 the mixed gel was composed of one single aggregated network, in which gelatin and WPC were homogeneously distributed. It was impossible to distinguish the gelatin from the WPC in the mixed network. The mixed gel at pH 7.5 showed a significantly higher G than the pure gels. As the gelatin phase was melted out for the mixed gel, a large decrease in G was observed. The pure gelatin gels, formed by a temperature decrease under high pressure, proved to be pH-dependent, showing an increase in aggregation as the pH increased from 5.4 to 7.5. A fine-stranded, transparent gelatin gel was formed at pH 5.4, while an aggregated, opaque gel was formed at pH 7.5. The stress at fracture for the gelatin gels decreased as the aggregation, and consequently the pore size, increased.  相似文献   
95.
Mixed gels of gelatin and whey protein concentrate were investigated, as well as their pure systems, by tensile tests and by dynamic oscillatory measurements. The systems were studied for homogeneous particulate whey protein gels at pH 5.4 and for inhomogeneous particulate whey protein gels at pH 4.6. The influence on the systems of the Bloom number of the gelatin component has also been investigated. Results of the fracture properties, such as stress and strain at fracture, indicate a transition in rheological properties. Results of the elastic modulus, obtained by tensile measurements, as well as the storage modulus, obtained by dynamic oscillatory measurements, both agree with predictions for phase inversions from the Takayanagi models as modified by Clark, which are in agreement with the fracture properties. The transition points are different for the different mixed gel series but take place between 1 and 3 wt% gelatin and 8 wt% whey protein concentrate, depending on factors such as the microstructure of the whey protein concentrate. Dynamic oscillatory measurements showed that gel formation of whey protein concentrate is unaffected by the presence of gelatin, which is in agreement with light microscopy results. Light microscopy revealed that the mixed gel systems were bicontinuous and that the whey protein network structure was unaffected by the presence of gelatin. It is postulated that the predicted phase inversions of the mixed gels are due to a shift in rheological properties without any phase inversions in the microstructure.  相似文献   
96.
Life cycle assessment (LCA) is a methodology that quantifies potential environmental impacts for comparative purposes in a decision-making context. While potential environmental impacts from pollutant emissions into water are characterized in LCA, impacts from water unavailability are not yet fully quantified. Water use can make the resource unavailable to other users by displacement or quality degradation. A reduction in water availability to human users can potentially affect human health. If financial resources are available, there can be adaptations that may, in turn, shift the environmental burdens to other life cycle stages and impact categories. This paper proposes a model to evaluate these potential impacts in an LCA context. It considers the water that is withdrawn and released, its quality and scarcity in order to evaluate the loss of functionality associated with water uses. Regionalized results are presented for impacts on human health for two modeling approaches regarding affected users, including or not domestic uses, and expressed in disability-adjusted life years (DALY). A consumption and quality based scarcity indicator is also proposed as a midpoint. An illustrative example is presented for the production of corrugated board with different effluents, demonstrating the importance of considering quality, process effluents and the difference between the modeling approaches.  相似文献   
97.
Juice-pressing residues, among them blackcurrant pomace, are valuable materials for being upgraded in food products. Their excellent nutritional profiles in line with their functional properties allow a wide range of applications. The current study was performed to evaluate the overall liking of a pomace-enriched thin crispy-baked bread product in five European countries, and to obtain suggestions for improvements. Moreover, data on the frequency of snack consumption, openness to new foods and an opinion on residues in food applications were acquired. Four hundred and sixty-six consumers from United Kingdom, Spain, Sweden, Italy and Germany were involved. On a 9-point hedonic scale, the pomace cracker was rated towards the direction of liking with 5.94 ± 1.90 on average. Contingency tables showed that the overall-liking correlated highly significant (p < 0.01) with the country of origin and sex of the respondents and their openness to new products. Significantly higher liking scores were provided by British and Spanish consumers and, among these respondents, savoury snacks were stated to be consumed most frequently. Therefore, the snack consumption frequency also appeared to be a driver for cross-national differences in hedonic responses. The consent for using pomace in food products was remarkably high (>90%) in all countries and stresses consumer awareness in terms of healthy longevity and sustainability.  相似文献   
98.
Synthetic calcium phosphates, despite their bioactivity, are brittle. Calcium phosphate- mullite composites have been suggested as potential dental and bone replacement materials which exhibit increased toughness. Aluminium, present in mullite, has however been linked to bone demineralisation and neurotoxicity: it is therefore important to characterise the materials fully in order to understand their in vivo behaviour. The present work reports the compositional mapping of the interfacial region of a calcium phosphate--20 wt% mullite biocomposite/soft tissue interface, obtained from the samples implanted into the long bones of healthy rabbits according to standard protocols (ISO-10993) for up to 12 weeks. X-ray micro-fluorescence was used to map simultaneously the distribution of Al, P, Si and Ca across the ceramic-soft tissue interface. A well defined and sharp interface region was present between the ceramic and the surrounding soft tissue for each time period examined. The concentration of Al in the surrounding tissue was found to fall by two orders of magnitude, to the background level, within ~35 μm of the implanted ceramic.  相似文献   
99.
Plants attacked by herbivorous insects emit volatile organic compounds that are used by natural enemies to locate their host or prey. The composition of the blend is often complex and specific. It may vary qualitatively and quantitatively according to plant and herbivore species, thus providing specific information for carnivorous arthropods. Most studies have focused on simple interactions that involve one species per trophic level, and typically have investigated the aboveground parts of plants. These investigations need to be extended to more complex networks that involve multiple herbivory above- and belowground. A previous study examined whether the presence of the leaf herbivore Pieris brassicae on turnip plants (Brassica rapa subsp. rapa) influences the response of Trybliographa rapae, a specialist parasitoid of the root feeder Delia radicum. It showed that the parasitoid was not attracted by volatiles emitted by plants under simultaneous attack. Here, we analyzed differences in the herbivore induced plant volatile (HIPV) mixtures that emanate from such infested plants by using Orthogonal Partial Least Squares-Discriminant Analysis (OPLS-DA). This multivariate model focuses on the differences between odor blends, and highlights the relative importance of each compound in an HIPV blend. Dual infestation resulted in several HIPVs that were present in both isolated infestation types. However, HIPVs collected from simultaneously infested plants were not the simple combination of volatiles from isolated forms of above- and belowground herbivory. Only a few specific compounds characterized the odor blend of each type of damaged plant. Indeed, some compounds were specifically induced by root herbivory (4-methyltridecane and salicylaldehyde) or shoot herbivory (methylsalicylate), whereas hexylacetate, a green leaf volatile, was specifically induced after dual herbivory. It remains to be determined whether or not these minor quantitative variations, within the background of more commonly induced odors, are involved in the reduced attraction of the root feeder’s parasitoid. The mechanisms involved in the specific modification of the odor blends emitted by dual infested turnip plants are discussed in the light of interferences between biosynthetic pathways linked to plant responses to shoot or root herbivory.  相似文献   
100.
The purpose of this study was to examine self-talk, year of university study, and gender as predictors of emotional intelligence in a diverse sample of 126 undergraduate participants (42 male, 84 female). Self-talk has been discussed in the literature as a means of enhancing self-awareness and self-regulation, both of which are considered important in the construct of emotional intelligence. Participants completed self-report questionnaires on self-talk and emotional intelligence. The results indicated that year of study and self-talk were significant predictors of emotional intelligence and were associated with emotional intelligence in a positive direction. Contrary to expectation, gender was not a significant predictor. The implications of the findings are discussed in terms of potential future research directions for the study of self-talk and emotional intelligence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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