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1.
Networks and Spatial Economics - This paper analyzes the socio-economic dimension of vulnerability and resilience from the viewpoint of connectivity. While no consensus has yet emerged on...  相似文献   
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Software and Systems Modeling - Mobile robots operate in various environments (e.g. aquatic, aerial, or terrestrial), they come in many diverse shapes and they are increasingly becoming parts of...  相似文献   
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We examine the performance of genetic algorithms (GAs) in uncovering solar water light splitters over a space of almost 19,000 perovskite materials. The entire search space was previously calculated using density functional theory to determine solutions that fulfill constraints on stability, band gap, and band edge position. Here, we test over 2500 unique GA implementations in finding these solutions to determine whether GA can avoid the need for brute force search, and thereby enable larger chemical spaces to be screened within a given computational budget. We find that the best GAs tested offer almost a 6 times efficiency gain over random search, and are comparable to the performance of a search based on informed chemical rules. In addition, the GA is almost 10 times as efficient as random search in finding half the solutions within the search space. By employing chemical rules, the performance of the GA can be further improved to approximately 12–17 better than random search. We discuss the effect of population size, selection function, crossover function, mutation rate, fitness function, and elitism on the final result, finding that selection function and elitism are especially important to GA performance. In addition, we determine that parameters that perform well in finding solar water splitters can also be applied to discovering transparent photocorrosion shields. Our results indicate that coupling GAs to high-throughput density functional calculations presents a promising method to rapidly search large chemical spaces for technological materials.  相似文献   
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In order to overcome the limitations of defining industrial specializations in digital industries through SIC codes, this paper suggests measuring the specializations and competences of these industries on the basis of the degree of digital technologies present in the products and services supplied. Metadata from CrunchBase are employed, as proxies of firms' specializations and competences which are defined as the fields of activity in which firms are involved. Applying a network analysis, these specializations and competences are linked to the recognition of emerging digital technologies and the strongest combinations of products and services. We tested the proposed methodology on London, a leading centre for the digital economy.  相似文献   
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In 1997 the Italian monitoring programme for pesticide residues in food comprised 7951 samples of 152 different foods for which a total of 275 pesticides were analysed. For 90 pesticides, the National Estimated Daily Intakes (NEDIs) were calculated by using the 90th percentile value and the food consumption data for the general Italian population. The calculated NEDIs were found to represent only a small portion of the respective Acceptable Daily Intake (ADI).  相似文献   
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Hen’s egg lysozyme (LYZ) is added to red wine for preventing malolactic activity. Sulphur dioxide and polyphenolic compounds can depress LYZ solubility and effectiveness, likely by sulphonation of enzyme disulphide bonds or protein binding, respectively. These phenomena were evaluated in either young red wine or model wine systems. A reliable and validated HPLC method was first developed in order to quantify soluble LYZ in wine (r95% = 10.7 mg l−1). The amount of insolubilized LYZ in red wine was related to the content of non-anthocyan flavonoids of low molecular weight and enzyme precipitation occurred in few minutes when flavonoid concentration exceeded 50 mg l−1. Interaction between sulphur dioxide and LYZ occurred in polyphenol-free model wine systems and for the first time the formation of mono-thiosulphonated LYZ was demonstrated. This reaction was favoured by increasing pH value and sulphur dioxide concentration. Nevertheless, sulphonation alone did not fully explain LYZ instability in model wine systems.  相似文献   
9.
The objective of this study was to investigate the influence of sodium caseinate films containing glycerol [glycerol:protein ratio 0.32 (w/w)] on lipid oxidation in cooked turkey breast meat slices. Slices were wrapped in films of different thickness (22, 42, and 58 μm) and were stored at 4 °C for 1, 2, 3 and 4 days. Lipid oxidation was measured using TBARS and hexanal assays on each day of storage while an olfactory sensory analysis was carried out on all the samples after 4 days of storage. TBARS values and hexanal levels of unwrapped samples (~6.0 mg MDA/kg and ~8.0 mg hexanal/kg) were significantly (P ≤ 0.05) higher than those of the casein film wrapped samples (~3.0 mg MDA/kg and ~3.0 mg hexanal/kg). Sensory analysis also showed significant (P ≤ 0.05) differences between wrapped samples and unwrapped samples, the former being perceived as less rancid. Thus wrapping in caseinate films may help reduce lipid oxidation in cooked turkey meat.  相似文献   
10.
The increasing emergence of fungicide-resistant pathogens requires urgent solutions for crop disease management. Here, we describe a structural investigation of new fungicides obtained by combining strobilurin and succinate dehydrogenase inhibitor pharmacophores. We identified compounds endowed with very good activity against wild-type Pyricularia oryzae, combined in some cases with promising activity against strobilurin-resistant strains. The first three-dimensional model of P. oryzae cytochrome bc1 complex containing azoxystrobin as a ligand was developed. The model was validated with a set of commercially available strobilurins, and it well explains both the resistance mechanism to strobilurins mediated by the mutation G143A and the activity of metyltetraprole against strobilurin-resistant strains. The obtained results shed light on the key recognition determinants of strobilurin-like derivatives in the cytochrome bc1 active site and will guide the further rational design of new fungicides able to overcome resistance caused by G143A mutation in the rice blast pathogen.  相似文献   
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