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In this paper, a novel Artificial Bee Colony algorithm is proposed to solve a variant of the Job Shop Scheduling Problem where only an interval of possible processing times is known for each operation. The solving method incorporates a diversification strategy based on the seasonal behaviour of bees. That is, the bees tend to explore more at the beginning of the search (spring) and be more conservative towards the end (summer to winter). This new strategy helps the algorithm avoid premature convergence, which appeared to be an issue in previous papers tackling the same problem. A thorough parametric analysis is conducted and a comparison of different seasonal models is performed on a set of benchmark instances from the literature. The results illustrate the benefit of using the new strategy, improving the performance of previous ABC-based methods for the same problem. An additional study is conducted to assess the robustness of the solutions obtained under different ranking operators, together with a sensitivity analysis to compare the effect that different levels of uncertainty have on the solutions' robustness. [ABSTRACT FROM AUTHOR]

An essay is presented on industrial agglomeration archetypes in the literature. Topics include fundamental concepts in literature with archetypical role on industrial agglomeration such as territory, function and technoeconomic paradigm; naming of industrial districts manifested during England's industrialization by the economist Alfred Marshall; history and evolution of economic development and socio-economic advancement and several archetypes like Becattinian districts and Isardian complexes.

Since its inception in the early 1990s, e-commerce has grown swiftly in Mexico, making inroads into some of the most dynamic sectors of the Mexican economy. The actual extent of e-commerce use, however, is still very limited, as diffusion is hindered by both the low income levels of most Mexican households and the fact that the overwhelming majority of business establishments are very small, lacking the resources to invest in computers and the business culture to go online. This article examines the emergence of e-commerce in Mexico arguing that the main drivers of the process have been the initiatives of large private firms and the work of specialized organizations. It concludes that this is not just a passing boom but a concrete step toward the rise of an Internet-based economy in Mexico along the lines of the New Economy that took shape in the United States in the 1990s and is assumed to spread into developing nations. [ABSTRACT FROM AUTHOR]

We report on the chemical design of chiral molecular junctions with stress‐dependent conductance, whose helicity is maintained during the stretching of a single molecule junction due to the stapling of both ends of the inner helix. In the reported compounds, different conductive pathways are observed, with clearly different conductance values and plateau‐length distributions, attributed to different conformations of the helical structures. The large chiro‐optical responses and the potential use of these molecules as unimolecular spin filters have been theoretically proved using state‐of‐the‐art Density Functional Theory (DFT) calculations, including a fully ab‐initio estimation of the CISS‐originating spin polarization which is done, for the first time, for a realistic molecular system. [ABSTRACT FROM AUTHOR]

We report on the chemical design of chiral molecular junctions with stress‐dependent conductance, whose helicity is maintained during the stretching of a single molecule junction due to the stapling of both ends of the inner helix. In the reported compounds, different conductive pathways are observed, with clearly different conductance values and plateau‐length distributions, attributed to different conformations of the helical structures. The large chiro‐optical responses and the potential use of these molecules as unimolecular spin filters have been theoretically proved using state‐of‐the‐art Density Functional Theory (DFT) calculations, including a fully ab‐initio estimation of the CISS‐originating spin polarization which is done, for the first time, for a realistic molecular system. [ABSTRACT FROM AUTHOR]

Examines the impact of economic liberalization on the computer industry. Stimulation of trade and investment; Diffusion of computer use; Increase in computer production.

Examines the impact of liberalization and economic integration on Mexico's computer sector. Process of liberalization at the macroeconomic level; Government policies for the computer industry; Trade in computer hardware from 1989 to 1996; Computer hardware production from 1989 to 1997.

Herein, we present, for the first time, a 2D-MOF based on copper and 4-hydroxypyrimidine-5-carbonitrile as the linker. Each MOF layer is perfectly flat and neutral, as is the case for graphene. High pressure X-ray diffraction measurements reveal that this layered structure can be modulated between 3.01 to 2.78 Å interlayer separation, with an evident piezochromism and varying conductive properties. An analysis of the band structure indicates that this material is conductive along different directions depending on the application of pressure or H doping. These results pave the way for the development of novel layered materials with tunable and efficient properties for pressure-based sensors. [ABSTRACT FROM AUTHOR]

Herein we evaluate the influence of an electric field on the coupling of two delocalized electrons in the mixed-valence polyoxometalate (POM) [GeV14O40]8− (in short V14) by using both a t-J model Hamiltonian and DFT calculations. In absence of an electric field the compound is paramagnetic, because the two electrons are localized on different parts of the POM. When an electric field is applied, an abrupt change of the magnetic coupling between the two delocalized electrons can be induced. Indeed, the field forces the two electrons to localize on nearest-neighbors metal centers, leading to a very strong antiferromagnetic coupling. Both theoretical approaches have led to similar results, emphasizing that the sharp spin transition induced by the electric field in the V14 system is a robust phenomenon, intramolecular in nature, and barely influenced by small changes on the external structure. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis, structure, and biological evaluation of a series of novel rifamycin derivatives, Rifastures (RFA) with potent anti-tuberculosis activity are presented. Some of these derivatives showed higher in vitro activity than rifabutin and rifampicin against not only Mycobacterium tuberculosis strains but also against MAC and Mycobacterium kansasii. [Copyright &y& Elsevier]

The article focuses on a study of the human-to-animal transmission of Mycobacterium tuberculosis infection in cattle in Spain from 2007 to 2009. Direct variable repeat spacer oligonucleotide typing was used to identify and genotype M. tuberculosis complex in tissue samples. An animal in farm 1 was co-infected with other mycobacteria, particularly M. avium hominissuis. It cites the importance of the use of liquid systems for the prompt confirmation of M. tuberculosis complex infection.