Los Olmos empiezan a recuperar sus territorios

El artículo describe la problemática de la grafiosis y el papel del proyecto LIFE+"Olmos Vivos" (LIFE13 BIO/ES/000556)en la recuperación de los olmos

A Berger-type theorem for metric connections with skew-symmetric torsion

We prove a Berger-type theorem which asserts that if the orthogonal subgroup generated by the torsion tensor (pulled back to a point by parallel transport) of a metric connection with skew-symmetric torsion is not transitive on the sphere, then the space must be locally isometric to a Lie group with a bi-invariant metric or its symmetric dual (we assume the space to be locally irreducible). We also prove that a (simple) Lie group with a bi-invariant metric admits only two flat metric connections with skew-symmetric torsion: the two flat canonical connections. In particular, we get a refinement of a well-known theorem by Cartan and Schouten. Finally, we show that the holonomy group of a metric connection with skew-symmetric torsion on these spaces generically coincides with the Riemannian holonomy.Comment: 13 pages; we add some new examples and fix minor misprints; final version to appear in Journal of Geometry and Physic

An Analysis of Litter Management Strategies in Olmos Basin Park: Evaluating Problems and Solutions

Olmos Basin Park is historically significant, biologically diverse and centrally located, yet it is decimated by trash. The park is predisposed to trash accumulation because of its geography and municipal setting. There are currently a few different litter management strategies active in the park. They include a contracted clean-up, the potential installation of a Bandalong Litter TrapTM Device, various Volunteer-Led clean-up projects, education focused strategies, and legal strategies. None of these strategies have been effective in significantly reducing the trash problem in Olmos Basin Park. A plastic bag ban, especially on that works within the frame work of existing bans, is the most effective strategy San Antonio could implement to reduce litter in Olmos Basin Park. The ban should be formulated with special consideration to San Antonio’s needs. Taking action on the litter problem in Olmos Basin Park will provide San Antonio’s with a safe, functional and central outdoor urban space

Archaeological Testing in the Devine Road Area North of Olmos Dam, San Antonio, Texas

During late January and early February 1978, archaeological testing was carried out in an area north of Olmos Dam, San Antonio, Texas (see Fig. 1) by personnel from the Center for Archaeological Research (CAR), The University of Texas at San Antonio. This work was performed under contract between CAR and the San Antonio River Authority. The area tested consisted of 16 acres bounded by Olmos Dam to the south, Devine Road to the west and Olmos Creek to the north and east. The objective of the testing was to determine whether any historic or prehistoric resources were present and, if so, to evaluate their significance prior to the use of the location as a borrow pit during the planned renovation of Olmos Dam. During the construction of Olmos Dam in the 1920s, a prehistoric site, 41 BX 1, was uncovered and mostly destroyed. Current testing in this area was designed to determine if any part of the site was left intact and to make recommendations for mitigation or protection. The archaeological testing was performed under the supervision of Dr. Tomas R. Hester, Director and Mr. Jack D. Eaton, Assistant Director, of CAR. The field work was directed by Cristi Assad with the assistance of Augustine Frkuska, Rebekah Halpern and Robert F. Scott. All notes, maps and materials collected are on file at the Center for Archaeological Research

Hydrosocial territories in the Atacama Desert: An ethnographic analysis of changing water practices in Toconao, Chile

Water shapes the territory and people’s lives through its flows, generating conflicts and harmony on its path. The flows of water frame the spatial configuration and are a fundamental element of the interaction between people, social institutions and their environment. Water is also an essential component of solidarity in the local culture and traditions of rural communities in the Atacama Desert in northern Chile. This study analysed an indigenous community, where a Corporate Social Responsibility (CSR) programme of a mining company resulted in spatial and social changes of water practices. The research is based on the perspective of political ecology and followed an ethnographic approach to provide an in-depth understanding of the relations between the company’s interventions and the hydrosocial territory. To achieve this, the research investigated changes in water management in the case of a CSR programme called Atacama Tierra Fértil (ATF), which was implemented in the Indigenous Community of Toconao in northern Chile. The analysis of the daily use of water resources revealed how multiple interests within the community in response to the CSR programme transformed the landscape and at the same time shaped the social development of the area. Personal interests, a commodification of natural resources and the control over the territory have reconfigured spaces of decision-making and social relations. The nuanced analysis of changes in the hydrosocial territory suggests that CSR programmes from the mining sector contribute to tensions, which are manifest in decreasing solidarity, cooperation, respect, and local autonomy within the community and its institutions

A Refined Scaling Law for Spatially Coupled LDPC Codes Over the Binary Erasure Channel

We propose a refined scaling law to predict the finite-length performance in the waterfall region of spatially coupled low-density parity-check codes over the binary erasure channel. In particular, we introduce some improvements to the scaling law proposed by Olmos and Urbanke that result in a better agreement between the predicted and simulated frame error rate. We also show how the scaling law can be extended to predict the bit error rate performance.Comment: Paper accepted to IEEE Information Theory Workshop (ITW) 201

The isotropy lattice of a lifted action

We obtain an algorithmic construction of the isotropy lattice for a lifted action of a Lie group $G$ on $TM$ and $T^*M$ based only on the knowledge of $G$ and its action on $M$. Some applications to symplectic geometry are also shown.Comment: minor modification