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21.
Giuseppe Espa Danila Filipponi Diego Giuliani Davide Piacentino 《Papers in Regional Science》2014,93(Z1):S113-S135
In this paper, spatial shift‐share decomposition is analysed when applied to Italian data on regional business change at plant level, over the period 2004–2009. A new type of spatial decomposition, which looks more effectively at neighbourhood influence, is introduced here. Notable results emerge from the empirical investigation. First, it can be seen that the spatial level of aggregation greatly affects results. Second, evidence of neighbourhood advantage in the Southern NUTS 3 regions is found, together with opposite results for the Central‐Northern NUTS 3 regions. Finally, evidence of positive industrial mix effects is only found in Central‐Northern Italy. 相似文献
22.
Zhidong Liu Hainan Zhao Lexin Shu Yanqing Zhang ChukwunweikeIkechukwu Okeke Li Zhang 《Drug development and industrial pharmacy》2015,41(3):353-361
Purpose: A novel brain targeting drug delivery system based on OX26 antibody conjugation on PEGylated cationic solid lipid nanoparticles (OX26-PEG-CSLN) was prepared.Methods: The Baicalin-loaded PEGylated cationic solid lipid nanoparticles modified by OX26 antibody (OX26-PEG-CSLN) were prepared by emulsion evaporation–solidification at low temperature method. The immune-gold labeled OX26-PEG-CSLN was visualized by transmission electron microscopy. The mean diameter and zeta potential of OX26-PEG-CSLN, PEG-CSLN and CSLN were determined using a Zetasizer. The entrapment efficiency of OX26-PEG-CSLN, PEG-CSLN and CSLN was determined by ultrafiltration centrifugation method. And the solid-state characterization of OX26-PEG-CSLN and CSLN were analyzed by X-ray. Pharmacokinetics studies were conducted by in vivo microdialysis in rat cerebrospinal fluid.Results: The results showed that the OX26-PEG-CSLN, PEG-CSLN and CSLN had average diameters of 47.68?±?1.65, 27.20?±?1.70 and 33.89?±?5.74?nm, Zeta potentials of ?0.533?±?0.115?mV, 11.200?±?0.500?mV and 11.080?±?1.170?mV and entrapment efficiencies of 83.03?±?0.01%, 92.90?±?3.50% and 97.83?±?0.19%, respectively. In the pharmacokinetics studies, the AUC value of OX26-PEG-CSLN was11.08-fold higher than that of the Baicalin solution (SOL) (p?0.01), and 1.12-fold higher than that of the CSLN (p?>?0.05); the Cmax value of OX26-PEG-CSLN was 7.88-fold higher than that of SOL (p?0.01) and 1.12-fold (p?0.01) higher than that of the CSLN, respectively.Conclusion: These results demonstrated OX26-PEG-CSLN could be a promising carrier to deliver drugs across the BBB for the treatment of brain diseases. 相似文献
23.
This paper analyses the characteristics of SMEs in less‐developed areas in comparison with more advanced economies. The conceptual framework includes different factors making up the so‐called ‘entrepreneurial quality’ of the SME sector: the personal characteristics of the entrepreneurs (motivations and previous experience), different dimensions of the SMEs’ entrepreneurial orientation, and the patterns of the SMEs’ insertion in national and global value chains. The empirical analysis uses data of SMEs in four different Spanish provinces representing examples of low income economies and comparatively high income ones, respectively. Results show the SMEs in the low income economies to be characterized by a lower entrepreneurial quality. 相似文献
24.
土壤中高产植酸酶芽孢杆菌菌株的筛选及鉴定 总被引:2,自引:0,他引:2
目的:从土壤中筛选高产植酸酶的芽孢杆菌菌株并作鉴定。方法:利用植酸酶能够水解植酸钙产生水解圈的特点,将样品处理后涂布于含有植酸钙的琼脂平板上,37℃培养3~4 d;挑取产生较大水解圈的菌落,再次划线分离,得单菌落,测定各菌株产植酸酶的活力;选取植酸酶活力最高的菌株,结合菌落形态、生理生化特征和分子生物学方法对其进行鉴定。结果:筛选到1株高产植酸酶的菌株,命名为ZJ0902,其酶活可达8 251U/mL。通过鉴定,该菌株为芽孢杆菌属中的Bacillus nealsonii。结论:该菌株的获得为植酸酶的产业化应用奠定了良好的基础。 相似文献
25.
26.
The cost of research & development (R&D) and quality management are always regarded as two major parts of total cost. The variable performance of R&D and quality design is an important index that will reflect the effectiveness of the cost reduction. This research has attempted to simultaneously vary all of the variables to achieve the global optimum for the optimal variable selections of R&D and quality design. Genetic algorithm (GA) can treat all of the variables for the global search. In this study, fuzzy refinement with orthogonal arrays was effective in improving the performance of the GA, and also showed the benefits of a good chromosome structure on the behavior of GA. It is also proposed the postponement design with temporal concept, to select the effective variables for the cost reduction of R&D and quality management design. The experimental results showed that tempo-postponement design will increase the flexibility and quick response for supply chain management. Hence, this approach can act as a useful guideline for researchers working on the optimization of the key variable selections for R&D and quality model design. 相似文献
27.
This section of News & Notes provides information on current news from Division 26. Included in this section are Minutes of the 2005 Business Meeting of the Society for the History of Psychology (APA Division 26), New Business, History of Psychology Around the World: The British Psychological Society’s History of Psychology Centre, Psychology on Film: The Prelinger Archives of Ephemeral Films and The Archives of the History of American Psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
This section of News & Notes provides the latest information about the Society for the History of Psychology. It contains Division news for the Division 26 of the American Psychological Association Society for the History of Psychology, meeting reports for the Society for the History of Psychology Program at the Convention of the Association for Psychological Science, call for papers, general member news, and reports from the field. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
Zaher Al 《Data & Knowledge Engineering》2005,52(3):333-352
Previous algorithms of data partitioning methods (DPMs) to find the exact K-nearest neighbors (KNN) at high dimensions are outperformed by a linear scan method [J.M. Kleinberg, Two algorithms for nearest neighbor search in high dimensions, 29th ACM Symposium on Theory of computing, 1997; R. Weber, H.-J. Schek, S. Blott. A quantitative analysis and performance study for similarity-search methods in high-dimensional spaces. in: Proc. of the 24th VLDB, USA, 1998]. In this paper, we present a “plug&search” method to greatly speed up the exact KNN search of existing DPMs. The idea is to linearize the data partitions produced by a DPM, rather than the points themselves, into a one-dimensional array-index, that is simple, compact and fast. Unlike most DPMs that support KNN search, which require storage space linear, or exponential [J.M. Kleinberg, Two algorithms for nearest neighbor search in high dimensions, 29th ACM Symposium on Theory of computing, 1997; M. Hagedoom, Nearest neighbors can be found efficiently if the dimension is small relative to the input size, ICDT 2003], in dimensions, the array-index requires a storage space that is linear in the number of mapped partitions. 相似文献
30.