Transformación de los espacios públicos de la ciudad patrimonial: el zócalo de la ciudad de Oaxaca

El Centro Histórico de la Ciudad Patrimonial, nos habla de cómo ha sido la historia del sitio y la de sus habitantes. Es un espacio complejo y heredado, en donde toda la población es dueña de alguna parte o forma del espacio. En el Centro Histórico se realizan actividades y funciones contradictorias, pero en la actualidad los espacios públicos que lo conforman se han transformado de acuerdo a las necesidades de la comunidad, a los planes y manejos de políticas públicas, por mencionar algunos factores. Los espacios públicos de los Centros Históricos se han transformado con el paso del tiempo debido a las necesidades y a la problemática a la que se ha enfrentado. Particularmente los Centros Históricos que son considerados Patrimonio Cultural de la Humanidad desafían a intereses y problemas específicos, ya que la transformación a la que están sujetos está vinculada a la oferta turística y comercial, olvidando la importancia que significa para la ciudad y los habitantes. La denominación de Patrimonio Cultural de la Humanidad a los Centros Históricos, ha generado en los espacios públicos problemas como: la fragmentación espacial, falsificación espacial, nuevas relaciones socio-espaciales, exclusión a ciertos grupos sociales. Este documento expone algunos conceptos, estudios y análisis de diferentes investigaciones realizadas a espacios públicos de Centros Históricos Patrimoniales, teniendo como objetivo reflexionar sobre el tema para sacar conclusiones que pueden generarnos líneas de investigación o de seguimiento. Ejemplificando y aterrizando lo mencionado anteriormente y llevando el tema a un entorno más cercano, se puede mencionar el zócalo del Centro Histórico de la ciudad de Oaxaca. El zócalo del Centro Histórico de la ciudad de Oaxaca, fue parte clave en la concepción de la ciudad y continúa siendo parte de la vida y expresiones oaxaqueñas. Este espació publico en la actualidad sigue siendo un sitio emblemático de la ciudad, su imagen a sido utilizada en propaganda turística, generando un punto atractivo para los visitantes, también continua siendo un espacio de la sociedad. El zócalo ha ido evolucionado con el paso del tiempo y aún así sigue formando parte de la identidad de los habitantes.The Historic Centre of the city talks about how the site's history and its habitants. Is a complex space, where the population in certain way owns some part of space. In the historic center you can find different and contradictories functions, but now the public spaces have been transformed according to the needs of the community, different plans and manage of public policies, just to name a few factors. The public spaces of the Historic Centre have been transformed over time due the needs and problems to which it has faced. Particularly Historical Centre who are considered World Heritage challenge specific interests and problems, most of the times the transformation is linked to the tourism and commerce, forgetting the importance that mean for the city and its habitants. The designation of World Heritage to the Historic Centre has created problems in public spaces such as spatial fragmentation, fake space, new socio-spatial relations and exclusion of certain social groups. This document presents some concepts, studies and analysis of different public spaces in Historic Centre, aiming to reflect on the subject to draw conclusions that can generate topics of research or monitoring. Exemplifying and quoting the public spaces in a Historic Centre to a close environment, this paper mentions the zócalo of the Historic Center of Oaxaca City. This public space has been an important element in the Historic Center of Oaxaca City, it was a key part in the conception of the city and continues to be a part of the residents life and expressions of Oaxaca. Today, this public space is still a feature of the town site, its image has been used in promotion of tourism, generating an attractive location for visitors, also remains an important area of society. The zócalo has evolved over time and still remains part of the identity of the habitants.Peer Reviewe

Resource preference of two stream detritivores in the laboratory largely differs from the supply of detritus below eucalypt plantations

Detritivores are pivotal in forest streams as they process detritus and promote secondary production. Many studies have addressed the preference of freshwater detritivores towards materials of differing quality. Nevertheless, few studies compare the resource preferences in the laboratory with the availability in the field. In the present study, feeding preferences of two stream detritivores (the caddisfly Sericostoma pyrenaicum and the amphipod Echinogammarus tarragonensis), over three native leaf species (alder, chestnut and oak) and an exotic species (eucalypt) were quantified in the laboratory. Preference for eucalypt leaves conditioned for 1, 2 and 3 weeks was also described. We then contrasted the preference patterns in the laboratory feeding experiments with a 15-month-long benthic standing stock time series of a stream below a native deciduous forest and another below a eucalypt plantation. Both detritivores preferred consuming alder leaves and more conditioned eucalypt leaves, although the amphipod was more selective than the caddisfly. The consumption preference in the laboratory was unmatched by the availability in the field, especially under eucalypt plantations and for the amphipod. Our results show that the strength of the preference for high-quality resources can differ among different taxa, which can modulate their response to land use changes.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This study was funded by the Spanish Dirección General de Enseñanza Superior e Investigación Científica (Project DGESIC PB98-0151) and finanacial support in terms of a predoctoral Grant to A. Otermin from Basque Government

Biofilter response to biomass reactivation for VOC treatment

[Abstract] This research has undertaken a comparative study on using a fresh activated sludge or a refrigerated/ reactivated sludge as active biomass source for biofiltration purposes. A sludge sample was initially selected based on the ratio between volatile solid content and total solid content before and after refrigeration at 6 oC for 90 days. The degradation rate of the activated sample for three addition doses of toluene was established before and after refrigeration. The same procedure was also carried out for ethylbenzene and p-xylene after refrigeration/reactivation. Surprisingly, the degradation rate for toluene was higher after refrigeration and the results were very similar for an addition of 2 and 8 µL. Subsequently, one biofilter was inoculated with the activated sample and another with the reactivated sample, and both were fed with toluene ranging from 2.6 to 26.2 g toluene m-3 h-1. Concerning the elimination capacity of both biofilters, no relevant differences were found. It was concluded that the active biomass degrading toluene was not affected by refrigeration, in spite of the fact that the SV/ST ratio decreased after the storage period. The elimination capacity of the other two biofilters (ethylbenzene and p-xylene) was highly influenced by the gas flow rate. 1 INTRODUCTION Environmental regulations for pollution control are frequently enacted before «suitable» (affordable, effective and environmentally friendly) technologies have been fully developed. Amongst biotechnologies, biofiltration is a seemingly simple system whose effectiveness relies on the optimization of several operating parameters and the selection of a suitable packing material and degrading biomas

El derecho laboral en Mexico : realidad y encubrimiento

1 archivo PDF (125 páginas)Los textos que se presentan interesan a los estudiosos del derecho porque confrontan realidad con hipótesis normativa; porque exhiben sin complicidad alguna de las conductas del Estado y de los empleadores contradiciendo los principios de un derecho laboral que tuvo pretensiones de convertirse en derecho social. En el primero de los textos, a partir del análisis del concepto de libertad, se abordan diversos condicionamientos al derecho de coalición y de huelga, acreditando las diferencias entre legitimidad y legalidad. En el segundo se analiza críticamente la requisa como figura jurídico-política utilizada por el Estado para nulificar los derechos colectivos de los trabajadores, especialmente el de huelga. Su estudio incluye, además del análisis jurídico de la figura mencionada, los términos de su aplicación en un sector laboral específico: los telefonistas. partiendo de la afirmación de que en tiempo de crisis el dominio sobre la clase trabajadora tiende a ser más sofisticado a través de nuevos instrumentos, constata y pondera la violación del marco legal en cuatro conflictos concretos, precisando en cada uno los hechos y conductas que permiten comprobar la hipótesis. Por último se cuenta la crónica de una lucha ejemplar que exhibe la actitud de las autoridades laborales y los mecanismos de intervención patronal, enfrentados a una gran energía obrera-que se toma indomable. PALABRAS CLAVE: Labor laws and legislation. Labor dispute

Land use drives detritivore size structure and decomposition through shifts in resource quality and quantity

Land use change and nutrient pollution are two pervasive stressors that can modify carbon cycling, as they influence the inputs and the transformation of detritus. Understanding their impact on stream food webs and on diversity is particularly pressing, as streams are largely fuelled by detrital material received from the adjacent riparian environment. Here we assess how a switch from native deciduous forest to Eucalyptus plantations and nutrient enrichment alter the size distribution of stream detritivore communities and decomposition rates of detritus. As expected, more detritus resulted in higher size-independent, or overall, abundance (i.e. higher intercept of size spectra). This change in overall abundance was mainly driven by a change of the relative contribution of large taxa (Amphipoda and Trichoptera), which changed from an average relative abundance of 55.5 to 77.2 % between the sites compared for resource quantity differences in our study. In contrast, detritus quality modified the relative abundance of large vs small individuals (i.e. size spectra slopes), with shallow slopes of size spectra (proportionately more large individuals) associated with sites with nutrient-richer waters and steeper slopes (proportionately fewer large individuals) associated with sites draining Eucalyptus plantations. Decomposition rates of alder leaves due to macroinvertebrates increased from 0.0003 to 0.0142 when relative contribution of large organisms increased (modelled slopes of size spectra: −1.00 and − 0.33, respectively), highlighting the importance of large sized individuals for ecosystem functioning. Our study reveals that land use change and nutrient pollution can greatly impair the transfer of energy through the detrital or ‘brown’ food web by means of intra- and inter-specific responses to quality and quantity of the detritus. These responses enable linking land use change and nutrient pollution to ecosystem productivity and carbon cycling.This work was carried out with financial support from the EU Commission within the RivFunction project (contract EVK1-CT-2001-00088). AL acknowledges the financial support by the mobility program Ikermugikortasuna-2019 of the Basque Government

The effect of sieve mesh size on the description of macroinvertebrate communities

Considerable time and effort is required to estimate the abundance and biomass of benthic macroinvertebrates, and often variable mesh size sieves are used to clean collected samples. We test whether the use of a mesh with a 1 mm pore size is adequate to obtain a valid description of a benthic macroinvertebrate community. Stream benthic surber samples were collected from 24 headwater streams. The densities, biotic indices and biological traits ofmacroinvertebrates retained in al mm mesh ('> 1 mm' fraction) were compared to the same descriptors for the of macroinvertebrates retained in a 0.5 mm mesh sieve ('total'). We found that, if only the large fraction (> 1 rnm) is examined, the cornmunity descriptors are affected. Nevertheless, the observed changes were proportional and predictable for all of the variables describing invertebrate communities. Statistical differenti­ation of the tested metrics between sites was similar for both mesh sizes. Depending on the aim of the study (e.g., environmental impact assessments), the use of a 1 mm mesh sieve would be sufficient in describing macroinvertebrate communities.Para las estimas de abundancia y biomasa, el procesado de las muestras en laboratorio de invertebrados bentónicos requiere un tiempo y esfuerzo considerable y generalmente implica el uso de tamices de diferente luz de malla para lavar la muestra. Nuestro trabajo trata de comprobar si es suficiente para una descripción válida de la comunidad el uso de un tamiz de malla de 1 mm de poro en el procesado de muestras. Con tal propósito se recogieron muestras bentónicas de río en 24 tramos de cabecera y se compararon densidades, índices bióticos y rasgos biológicos de los invertebrados que eran retenidos en un tamiz de luz de malla de 1 mm (fracción '>1 mm') con los obtenidos usando una de 0.5 mm ('total'). Nuestro estudio revela que el análisis exclusivo de la malla gruesa afecta a los descriptores de la comunidad. Sin embargo, los cambios observados son proporcionales para todas las variables y se pueden predecir bien con ecuaciones lineales. Por otro lado, la diferenciación estadística entre estaciones es similar usando ambos tipos de malla, lo que en definitiva sugiere que, dependiendo del objetivo del estudio (por ejemplo, evaluación de impacto ambiental), el examen de la fauna retenida en un tamiz de 1 mm de poro puede ser suficiente para la descripción de las comunidades de macroinvertebrados

Analysis of 5G-TSN Integration to Support Industry 4.0

Time Sensitive Networking (TSN) is becoming the standard Ethernet-based technology for converged networks of Industry 4.0 due to its capacity to support deterministic latency requirements. However, it cannot provide the required flexibility to support mobile industrial applications required for the factories of the future. This could be enabled through the integration of wireless technologies in factories, and in particular of 5G and Beyond networks since they have been designed to support ultra-reliable and low-latency communications. This has triggered significant interest to integrate 5G and TSN networks, and first frameworks for such integration have been defined. However, the work is at early stages and the solutions to effectively integrate the two networks so that 5G can support TSN QoS levels are yet to be designed. This paper discusses current research and standardization work on 5G-TSN integration, and quantifies for a closed loop control application the 5GS bridge delay. The paper uses an example based on 5G-ACIA [1] to discuss open technical and research challenges to effectively integrate 5G and TS

The path towards herd immunity : predicting COVID-19 vaccination uptake through results from a stated choice study across six continents

Despite unprecedented progress in developing COVID-19 vaccines, global vaccination levels needed to reach herd immunity remain a distant target, while new variants keep emerging. Obtaining near universal vaccine uptake relies on understanding and addressing vaccine resistance. Simple questions about vaccine acceptance however ignore that the vaccines being offered vary across countries and even population subgroups, and differ in terms of efficacy and side effects. By using advanced discrete choice models estimated on stated choice data collected in 18 countries/territories across six continents, we show a substantial influence of vaccine characteristics. Uptake increases if more efficacious vaccines (95% vs 60%) are offered (mean across study areas = 3.9%, range of 0.6%–8.1%) or if vaccines offer at least 12 months of protection (mean across study areas = 2.4%, range of 0.2%–5.8%), while an increase in severe side effects (from 0.001% to 0.01%) leads to reduced uptake (mean = −1.3%, range of −0.2% to −3.9%). Additionally, a large share of individuals (mean = 55.2%, range of 28%–75.8%) would delay vaccination by 3 months to obtain a more efficacious (95% vs 60%) vaccine, where this increases further if the low efficacy vaccine has a higher risk (0.01% instead of 0.001%) of severe side effects (mean = 65.9%, range of 41.4%–86.5%). Our work highlights that careful consideration of which vaccines to offer can be beneficial. In support of this, we provide an interactive tool to predict uptake in a country as a function of the vaccines being deployed, and also depending on the levels of infectiousness and severity of circulating variants of COVID-19

Experimental study on the stability and transient behavior of a closed-loop two-phase thermosyphon (CLTPT) charged with NOVEC 649

Currently, the growing need for efficient refrigeration resources in the industrial sector has led to an increasing interest in finding technologies with a higher heat removal potential and better cooling performance. Along these lines, two-phase liquid cooling appears to be a very interesting solution, with the CLTPT (closed-loop two-phase thermosyphon) being one of the leading alternatives. Most works in the scientific literature study loop thermosyphons that work in flow boiling conditions in steady state. The present paper analyzes the transient thermal behavior of a pool boiling CLTPT gravitational channel as a passive cooling system using NOVEC 649 as working fluid. The evaporator works with two submerged cylindrical heaters that represent different heat sources located in different positions. The initial transient behavior and consequent instabilities of a laboratory-scale facility were studied, followed by a stability analysis for various power inputs. Parameters such as temperature and pressure along the experimental setup were monitored, and the effects of internal pressure and room conditions were also tested. The results show some instabilities in the process to start the flow circulation and a relative stability and quick adaptation to changes when circulation is reached. The temperature in the evaporator chamber was highly homogeneous during the whole process; however, the temperature changes in the riser and the loop top were delayed with respect to the evaporator zone. The analysis shows several pressure and temperature raises before the vapor flux reaches the condenser. When the flow circulation is established, the system becomes highly stable and thermally homogeneous, decreasing the thermal resistance when increasing the power input. The stability analysis also showed that, when the system reaches the steady state, the changes in the power input produce a transient increase in the pressure and temperature of the fluid, followed by a quick decrease of the previous steady state values. The heat transfer analysis in the evaporator shows a higher heat flux on the upper heater caused by the buoyancy flow that rises from the lower heater. It was also observed that the lower heater reaches the CHF point with a lower heat flux.Ministerio de Ciencia, Innovación y Universidades | Ref. RTI-2018-100765-B10