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61.
Gorgievski-Duijvesteijn Marjan J.; Bakker Arnold B.; Schaufeli Wilmar B.; van der Heijden Peter G. M. 《Canadian Metallurgical Quarterly》2005,10(3):210
This study of 513 Dutch farmers tested a dynamic equilibrium model of resources (an extension of the conservation of resources theory; S. E. Hobfoll, 1989, 1998, 2001). With structural equation modeling, the advantages of a 3-wave longitudinal design were comprehensively used, such as addressing bidirectional causal effects and within-individual vs. between-individual change. This allowed for a careful analysis of the management function of resources in the stress process. Results showed that well-being had stronger within-person stability than finances. Increased levels of financial problems temporarily increased psychological distress but not self-reported illness. Conversely, farmers with higher stable baselines of psychological distress also had higher baselines of self-reported illness and experienced more negative changes in their financial situation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
W J Stut J P de Valk H W Didden A R Bakker B M ter Haar Romeny 《Computer methods and programs in biomedicine》1989,28(1):63-70
Since the construction of picture archiving and communication systems (PACS) appears to be extremely difficult, computer modelling and simulation are used as decision support tools. The package MIRACLES (Medical Image Representation, Archiving and Communication Learned from Extensive Simulation) has been developed at BAZIS in order to support the construction of simulation models of image information systems. This article discusses the application of MIRACLES to a prototypical PACS as being installed in a clinical environment. Attention is focussed to the required system analysis and difficulties which arose during the construction of the simulation model. The emphasis is on the presentation of the results of the simulation study, which show that simulation can be fruitfully used to predict, to analyse and to assist in solving performance problems. The simulation study confirmed assumptions and suppositions concerning both the system performance itself and strategies to improve the performance. The study also resulted in a number of concrete recommendations which might be useful for the set-up of the prototypical PACS. 相似文献
63.
Iris C. Zampini Roxana Ordoñez Norberto P. Giannini Pedro G. Blendinger María Inés Isla 《Food research international (Ottawa, Ont.)》2011,44(7):2345-2351
Fruits are known as good sources of phytochemicals, essential to prevent degenerative diseases like cancer and cardiovascular diseases. They contain a variety of antioxidants, which are useful to scavenge radical oxygen species (ROS). Considering the importance of natural products as a functional food, comparative studies between the antioxidant activity (AOA) and antimutagenic properties as well as phytochemical profile of Cactaceae fruits (Lepismium lorentzianum, Lepismium lumbricoides, Rhipsalis floccosa, and Pfeiffera ianthothele) from Argentinean Yungas, were performed. Different assays were applied: ABTS radical scavenging capacity, inhibition of lipid peroxidation using ??-carotene-linoleate model system and mutagenicity/antimutagenicity by Ames test. A pigment like betalain was detected in fruits of both Lepismium species; L. lorentzianum aqueous extracts showed a higher pigment content (60.6 mg BE/100 g FM) than L. lumbricoides (9.2 mg BE/100 g FM). Fruit preparations of L. lorentzianum (aqueous and ethanolic extractions) showed significantly higher total phenolic compound and pigments content than the other berries. In all preparations, high antioxidant activity was demonstrated. Lepismium species were more active than Rhipsalis and Pfeiffera (SC50ABTS values between 1.3 and 4.5 ??g/ml and IC50 ??-carotene-linoleate values between 9 and 45.8 ??g/ml). A significant correlation between pigment and phenolic compounds content and AOA was observed. The preparations showed no sign of mutagenicity at tested concentrations (until 50 ??g/plate). A significant antimutagenic effect was observed for L. lumbricoides, and a weak effect was shown for P. ianthothele and R. floccosa. Because of the diversity and abundance of bioactive phytochemicals found in these species, food, cosmetic, and pharmaceutical applications could be proposed. 相似文献
64.
R. Iris Bahar Dan Hammerstrom Justin Harlow William H. Joyner Jr. Clifford Lau Diana Marculescu Alex Orailoglu Massoud Pedram 《Computer》2007,40(1):25-33
Although nanoelectronics won't replace CMOS for some time, research is needed now to develop the architectures, methods, and tools to maximally leverage nanoscale devices and terascale capacity. Addressing the complementary architectural and system issues involved requires greater collaboration at all levels. The effective use of nanotechnology calls for total system solutions 相似文献
65.
66.
Thuy Van Lam van Dr. Teodora Ivanova Dr. Kornelia Hardes Miriam Ruth Heindl Dr. Rory E. Morty Prof. Eva Böttcher-Friebertshäuser Prof. Iris Lindberg Dr. Manuel E. Than Dr. Sven O. Dahms Prof. Torsten Steinmetzer 《ChemMedChem》2019,14(6):673-685
The activation of viral glycoproteins by the host protease furin is an essential step in the replication of numerous pathogenic viruses. Thus, effective inhibitors of furin could serve as broad-spectrum antiviral drugs. A crystal structure of an inhibitory hexapeptide derivative in complex with furin served as template for the rational design of various types of new cyclic inhibitors. Most of the prepared derivatives are relatively potent furin inhibitors with inhibition constants in the low nanomolar or even sub-nanomolar range. For seven derivatives the crystal structures in complex with furin could be determined. In three complexes, electron density was found for the entire inhibitor. In the other cases the structures could be determined only for the P6/P5-P1 segments, which directly interact with furin. The cyclic derivatives together with two non-cyclic reference compounds were tested as inhibitors of the proteolytic activation and replication of respiratory syncytial virus in cells. Significant antiviral activity was found for both linear reference inhibitors, whereas a negligible efficacy was determined for the cyclic derivatives. 相似文献
67.
This paper explores Canada's approach to water governance. It argues that fragmented governance has had negative impacts on Canada's ability to manage water resources adequately (particularly in the context of urbanization, agriculture and resource extraction), and to deal with new issues (such as climate change). Further, it argues that Canada's highly decentralized approach to water governance creates challenges of integration, coordination and data availability. The paper explores possible future strategies for innovations in water governance that may have the potential to improve water management outcomes. 相似文献
68.
This paper explores the scale and scope of transformations in the environmental planning field, and the factors that may advance or impede their widespread adoption. A conceptual model is offered which examines scope (defined as type, breadth and structure of the transformation), and the scale of its impact (categorized as stakeholder, organizational, institutional or societal) and applies it to the analysis of several cases in Israel where environmental transformations, affecting the way in which planning is conducted, have been adopted. Conclusions include identification of conditions for facilitating and advancing transformations, including knowledge of innovative alternatives, initiative, willingness to adopt new practices, and identification of policy windows that emerge during conflict, reform, or crisis. The fostering of relations between environmental non-government organizations and planning systems and leadership roles are also significant in catalyzing environmental transformation. 相似文献
69.
The combination of building information modeling (BIM) and integrated project delivery (IPD) has been widely supported in the literature as a solution to the problems of limited collaboration in the construction industry. BIM and IPD have been described as cooperative means of achieving sustainable benefit to stakeholders. However, most studies focused on the technological challenges involved, with reference mainly to the sustainable economic and environmental benefits of the combination, while the sustainable sociocultural benefits have not been extensively explored. In this study, these issues are addressed by highlighting the importance of implementing BIM as a social system, using BIM corporate social responsibility (CSR) application model, in a BIM-based IPD project. This CSR model of BIM application (CSR-BIM model) serves as a benchmark for examining the achievement of a sociocultural benefits from the project. Social network analysis (SNA) was employed as an analytical method for examining the inter-organizational communication network during the design stage in relation to the CSR-BIM model. The SNA studies were conducted to compare the optimal model findings and the actual findings, focusing on clusters, ego-network clusters and the centrality of the players. The comparison—which related only to the BIM communication platform, in the context of the professionals—found a distinction between the BIM manager and the project team and its management, presenting separate and partial clusters. The evaluation also identified the low centrality of the BIM manager relative to the optimal option. In response, recommendations are made to implement the CSR-BIM model as a management measure to better support a sustainable sociocultural project. 相似文献
70.
Jacomijn Pluimers Carolien Kroeze Evert Jan Bakker Hugo Challa Leen Hordijk 《Nutrient Cycling in Agroecosystems》2001,60(1-3):209-218
In this paper, present-day emissions of greenhouse gases and acidifying compounds from agriculture are analysed at the farm level. Quantitative estimates are given for these emissions from three nested systems in the Netherlands: the agricultural sector, greenhouse horticulture, and tomato cultivation under glass. Total emissions are subdivided into emissions from biogenic sources and abiogenic sources. We conclude that, although most of the emissions from the agricultural sector have biogenic sources, those from abiogenic sources should not be neglected. Abiogenic emissions are mainly from greenhouse horticulture. The cost-effectiveness of options to reduce carbon dioxide (CO2) and nitrogen oxides (NOx) emissions from on-farm combustion of natural gas in tomato cultivation under glass is analysed. An inventory is given of technical reduction options that are presently available in practice. Based on information about the costs and the reduction potential of each option, cost-efficiency curves are derived for both types of emissions. Relative to a situation where none of the described options were applied (early nineties), CO2 and NOx emissions from tomato cultivation can be reduced at most by about 70% and 75%, respectively, by combinations of technical options. This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献