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Parachondria neglectus is a terrestrial mollusk endemic of Cuba. This species constitutes the only report of the Annulariidae family in the municipality of Manzanillo, Granma province. In the present study, the temporal dynamics of the structural subniche of a population of P. neglectus was characterized. Thirty expeditions were carried out between December 2013 and February 2015. 83.9 % of the mollusks were found on the ground (around the base of trees and shrubs) and 16.1 % used the trunk of eight plant species as diurnal resting substrate. The test of independence performed using a 2×2 contingency table with Yates correction showed that in the population the frequency of using one substrate or another depends on the occurrence or not of rainfall (X2 = 214.88; P = 0.0001). This species was found at an average trunk distance of 13 ± 6.42 cm. The C-index values indicated marked preference of this mollusk for Swietenia mahagoni during all climatic periods sampled. During the rainy season this species also showed statistically significant preferences for Cordia gerascanthus, Ehretia tinifolia and Bursera simaruba. For the population, the height above the ground presented a mean value of 153.5 ± 71.3 cm. The heights above the ground reached by this species on rainy and non-rainy days showed statistically significant differences (U = 21519.5; P < 0.001). [ABSTRACT FROM AUTHOR]

The COOPMERCASAN peasant market began its operation in 2011, providing fresh and safe agricultural products to the population of Florence. In these eight years of operation, they have had successes and failures, they have also received the support of different institutions, however, to date, their current realities are unknown, as well as the challenges, which have been changing over time. It is because of the above that this research sought to build the dynamics of this experience through self-reflection, base information for decision-making, and the orientation of their improvement actions. The work was carried out in the municipality of Florence, the tools for gathering the information were surveys, interviews, and participant observation. Among the main findings, it was discovered that, although the market has managed to position itself with an interesting customer base, its offer is not meeting expectations in terms of the volumes and diversity demanded by customers and that, although the vast majority of the support provided by the institutions has been directed towards organizational strengthening processes, it continues to be the weakest aspect. [ABSTRACT FROM AUTHOR]

The interconnection of the Central Interconnected System (SIC for its initials in Spanish) with the Northern Interconnected System (SING) have been one of the trending topics in the year 2013 in the Chilean electric industry. Two are the projects that are on target for the interconnection; a high voltage alternating current (HVAC) 500 kV connection, proposed by the French utility GDF SUEZ, and a high voltage direct current (HVDC) ±500 kV planned by the CNE, the Chilean electric regulator entity. Both projects have important differences in technology and there's not too much technical evidence of the problems that could arise in the operation, caused by the SIC-SING interconnection. Low frequency oscillations are studied in this work, using modal analysis for both interconnection projects. A SIC-SING model is developed using DigSilent software, considering 2019 as the year of a possible union of the networks. Two generation scenarios are studied; one where the central system (SIC) sends 1.000 MW to the northern system (SING), and another one where the SING sends 800 MW to the SIC. The modal analysis results show that interconnecting both systems with the HVAC gives arise to a 0.5 Hz unstable oscillation mode. This unstable mode has it origin on the interconnection and it's related to a group of steam machines on the SING system. Whether the SIC-SING system is connected with the HVAC or the HVDC, 0.9 Hz weakly damped modes are observed in both systems. These modes are related to the evolution of the systems at 2019. [ABSTRACT FROM AUTHOR]

Se presenta una reseña del artículo "Close-packed structure dynamics with finite-range interaction: Computational mechanics with individual layer interaction" de E. Rodríguez-Horta, E. Estevez-Rams, R. Lora-Serrano y R. Neder, y publicado en la revista "Acta Crystallographica."