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Copyright of Estado & Comunes, revista de politicas y problemas publicos is the property of Instituto de Altos Estudios Nacionales (IAEN) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecología Política is the property of Fundacio ENT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecología Política is the property of Fundacio ENT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecología Política is the property of Fundacio ENT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Neutrosophic Computing & Machine Learning is the property of Multimedia Larga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Amazonia Investiga is the property of PRIMMATE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Composting is the process of decomposition of organic solid waste by mixed populations of microorganisms under controlled conditions. The objective of this research is to evaluate the effect of the addition of efficient microorganisms in different doses and the dynamics of their physical and chemical properties during the whole composting process. Four treatments T1 (0L EM/5L H2O), T2 (0.1L EM/5L H2O), T3 (0.5L EM/5L H2O), T4 (1L EM/5L H2O) with 110 days duration were evaluated. The results showed that the temperature control shows that the treatment with the highest dose of efficient microorganisms remained longer in the thermophilic phase, unlike the control treatment (T1), therefore a greater sanitization. As for pH, the treatments started with a slightly acid pH and later increased to 9-10 and then decreased to values of 9-8 in the treatments T2, T3 and T4. For EC, treatments T1, T2 and T3 presented values higher than 5.00 dS m-1, however, treatment T4 presented values of 4.78 dS m-1, which would be within the acceptable range according to different regulations. As for total organic carbon (TOC), a higher percentage of mineralization is evidenced in treatment T4 and a lower percentage in T1 with respect to initial carbon. In the case of total nitrogen, there is evidence of an increase in treatments T2, T3 and T4 with microbial inoculant over the control treatment, attributing this to the nitrogen-fixing bacteria present in the efficient microorganisms. Finally, it can be evidenced that CO2 emissions are an important parameter to identify the biological activity and stability of the compost, as well as the CO2 emissions produced by the transformation of TOC is directly proportional to the temperature. This shows that the incorporation of efficient microorganisms benefits the composting processes causing higher biological activity as a consequence; increase of temperature for an adequate sanitization, an increase of the TOC mineralization percentage, improvement of pH and conductivity conditions, an increase of the total nitrogen percentage and the stability of the final compost. [ABSTRACT FROM AUTHOR]

This research evaluated the management of solid waste and its impact on the inhabitants of the "12 de Marzo" parish. The research is qualitative, a descriptive approach was used. The survey technique and interview were applied. The study will be bibliographic and field. The results were processed in Statistical Package for the Social Sciences applying the Alpha Cronbad coefficient, obtaining 93.5%, being considered reliable and the free software Geographic Information System QGIS, a high daily amount of waste was evident, indicating a critical need for collection and management systems of waste. It is concluded that critical areas must be highlighted for intervention and the development of effective policies. [ABSTRACT FROM AUTHOR]

Copyright of Jangwa Pana is the property of Revista Jangwa Pana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ecología Política is the property of Fundacio ENT and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Globally, there has been a significant increase in solid waste with environmental implications. Management and integrated management proposals, based on what type of waste is produced and in what proportion, are required to mitigate the generation of solid waste and its effects. This article reports the results of a characterization and quantification study at the Liceo V.A.L. school in Bogotá, D.C. Three categories of analysis and 4 sampling points were established. A total of 180 samples were studied during the years 2023 and 2024. The total amount of solid waste generated was 128.34 kg. Sixty-four percent of the waste generated corresponded to non-usable waste (black container), 21 % to organic waste (green container) and 15 % to usable waste (white container). The daily per capita generation was 0.03 kg/person-day. The highest solid waste generation was observed in the cooperative area (35 %) and the lowest in the preschool area (11 %). Incorrect separation at the source explains the high percentage of solid waste in the black container. The characterization of the waste in the white container showed that PET (1) waste (26 %) and plastic yogur containers (HDPE) (2) (20 %) presented the highest percentage by mass. These wastes have a high recycling potential, which is why it is essential to improve the separation process in order to reduce the amount of solid waste disposed of in the landfill. [ABSTRACT FROM AUTHOR]

Castillo Grande, located in Huánuco - Peru, presents the problem of contamination produced by the increase of solid waste, especially organic waste, which is not used, so the way of degradation of such waste is proposed, proposing the objective of evaluating the action of three types of effective microorganisms in the degradation of organic solid waste and in the production of compost with parameters chemical. The methodology used was a completely randomized experimental design, with three treatments (Compost1, Compost2 and Compost3) and three repetitions per treatment, where the analysis of variables, such as the degradation period of organic solid waste and chemical parameters of the compost, were a function of the average values and dispersion. The results do not report statistically significant differences between treatments in the degradation period; but it does in certain chemical parameters. Compost1 is the one that reported the shortest degradation period, and higher organic matter contents in the dry state, moisture, nitrogen, phosphorus, potassium, magnesium, sodium, zinc and manganese, largely complying with the levels established by the Peruvian Technical Standard 201.208:2021; while the highest Ca and Fe content was recorded with Compost3. Concluding that the effective microorganisms from the leaf litter are suitable for decomposing organic solid waste and producing compost in less time and with good chemical parameters. [ABSTRACT FROM AUTHOR]

The comparison of economic results in the Sogamoso central Macro route of the solid waste utilization network is based on the evaluation of operations research alternatives, applicable to situations that require decision making, which range from network optimization, the technique from PERT/CPM projects, to the use of software to measure efficiency and effectiveness in the search for better results. Network problems turn out to be abstract representations of activities or processes for determining the critical path with the use of fewer resources, in this case economic. Sogamoso's Central Macro Route includes routing models based on the shortest distance where costs are directly associated with this variable. The routing models will consider the nodes as the collection points or fixed point containers and the arcs as the paths between each of them. [ABSTRACT FROM AUTHOR]

The article aims to review existing methodologies to assess heavy metal (HM) pollution associated with road sediment, which is discharged into urban water bodies. The systematic literature review used a citation frequency index (Q) to establish the importance of the variables considered. The results indicate that the key variables to be considered are as follows: Precipitation (Q = 0.83), total solids (0.70), heavy metals (0.61), hydrocarbons (0.32), solid waste (0.27) and runoff (0.23). The most relevant HMs are the following: Zn (0.79), Cu (0.76), Ni (0.68), Cr (0.65) and Pb (0.46). The evaluation methodologies detected are as follows: Chemical analysis (0.30), biological impact (0.29), numerical modeling (0.29), granulometric analysis (0.29) and laboratory simulations (0.22). The major HMs in road environments are Zn and Ni, and total solids can be used as indicators of HMs in road runoff. [ABSTRACT FROM AUTHOR]

Copyright of Estudios de la Gestión is the property of Universidad Andina Simon Bolivar, Sede Ecuador and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Estudios de la Gestión is the property of Universidad Andina Simon Bolivar, Sede Ecuador and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Actas de Diseño is the property of Facultad de Diseno y Comunicacion, Fundacion Universidad de Palermo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Trabajo Social is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Maguaré is the property of Universidad Nacional de Colombia, Departamento de Antropologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The integrated management of solid waste at the household level involves adequate collection logistics for recovery by waste collectors. The objective of this study was to optimize the route for access to waste at strategic points in the city of Manizales (Colombia), in addition to analyzing the qualitative characteristics related to a process of sensitization of the executing personnel. The integration of the numerical inputs and study variables was carried out through the application of the Shortest Route optimization algorithm, while the SWOT matrix was implemented to analyze the operational satisfaction conditions. The results generated a reduction in routes in 62.5% of the cases, obtaining savings of up to 28.61% of kilometers traveled daily by the reclaimers. It was also identified that factors such as topography and climate have a direct impact on collection activities. [ABSTRACT FROM AUTHOR]

Copyright of Iluminuras is the property of Revista Iluminuras and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Inadequate solid waste management in educational centers aggravates environmental problems. Train and promote ecological awareness in the collection and classification of valuable urban solid waste within an educational community, in order to promote the reduction, reuse and recycling of waste. Training focused on reuse and recycling was developed, including the ReciclaTec campaign, promoting a conscious environmental culture among students. After the implementation of the talks, the waste generated at the institute was Polyethylene Terephthalate (PET; 201.1 kg), cardboard (55.2 kg), paper (204.2 kg) and aluminum (3.8 kg), totaling 464.3 kilograms, over a period of time of four months. Constant training and the inclusion of marked containers are essential to maintain and improve waste classification and management, promoting effective environmental education and the significant reduction of discarded waste. [ABSTRACT FROM AUTHOR]

The aim of this text is to address the historical structuring of the waste problem in Mexico and the emergence and evolution of its regulations, highlighting the influence of regulations from the United States. The history of solid urban waste regulations in both countries is briefly reviewed, recognizing that they result from second and third-level processes in order to uncover epistemic frameworks and empirical domains underlying conflicts through an analytical and comparative documentary method from interdisciplinarity and complex systems perspectives. The influence of American regulations on those of our country is revealed, stemming from structural inertias of industrialization and neoliberalism. This text examines how this matter was regulated in different Mexican sanitary codes of the last century until the General Law for the Prevention and Integral Management of Waste, through environmental laws and their regulations over the last 40 years as well as regulations on public services in Mexico City; without neglecting the review of Mexican municipal law. Likewise, the history of American waste legislation from the 1960s to the present is reviewed for a comparative perspective. It is concluded that by understanding the genesis of the problem and the construction of solutions from neighboring countries rather than simply emulating them, true opportunities to solve the waste problem in Mexico and promote respect for human rights would be facilitated. [ABSTRACT FROM AUTHOR]

This work determined the ecological footprint of the National Center for Applied Electromagnetism, a science institution attached at the Universidad de Oriente, Santiago de Cuba. The categories analyzed to carry out the calculations of CO2 emissions and the ecological footprint were: Water, Built surface, Electricity Consumption, Mobility, Paper, Non-hazardous solid waste, Hazardous waste, Food, Services and Production of Magnetic Conditioners. The methodology of Doménech (2009) and the methodology for calculating the ecological footprint in universities of López Álvarez et al. (2009) of the Sustainable Development Office, University of Santiago de Compostela were used as a basis. The results obtained for the year 2022 reflect that the National Center for Applied Electromagnetism needs an area of 52,984 ha/year of forest to regenerate the natural resources that the center uses for the satisfaction of it social demand. Similarly, it requires 89,096 hag standard forest to assimilate CO2 emissions. [ABSTRACT FROM AUTHOR]

Copyright of Revista Venezolana de Gerencia (RVG) is the property of Revista de Filosofia-Universidad del Zulia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Within households, bulky solid waste serves as the predominant breeding ground for mosquitoes that transmit dengue fever. The aim of this study is to identify and describe the relationship between material and subjective factors, using socioecological theoretical frameworks for health prevention. A descriptive cross-sectional study is conducted, using a simple random sample of 350 households in Asunción, Paraguay. To compare households based on the presence or absence of large breeding sites, the chi-square test, non-parametric Mann-Whitney-Wilcoxon statistical test, and Yuen's robust T statistical test is employed. Additionally, a multivariate logistic regression analysis was carried out to determinate the Odd Ratio (OR). The study concludes that individualistic approaches in dengue prevention must be transcended and management capacities in homes must be increased by addressing environmental barriers and social beliefs, given the factor that most significantly explaines the presence of obsolete objects in homes is the belief that these items could prove useful in the future. In the multivariate analysis, the perception of usefulness of the potential breeding sites was one of the two significant variables that explain this behavior. The other significant variable was the low coverage of waste collection. [ABSTRACT FROM AUTHOR]

The purpose of this research was to determine the composition of solid waste generation in the district municipality of Santa, Peru. The method used was quantitative, the research was applied and descriptive, quantitative data was analyzed, which defines the composition of solid waste through the different tables and graphs, likewise, 113 were selected households. Concluding that the general physical composition of the solid household waste in the district of Santa, 75.38% is reusable waste composed of organic waste, paper, plastics, metals among others, while 24.62% is non-reusable waste. composed mainly of 4.46% plastic bags, 3.56% inert soil, 7.96% uncategorized waste. [ABSTRACT FROM AUTHOR]

Solid waste is waste materials that affect a natural deposit, affecting the ecosystem around it, making it impossible for the emergence and permanence of life spontaneously, due to the high rate of polluting agents and toxic components, therefore, the challenge currently is to convert processes to give practical uses to this waste, trying to mitigate the environmental impact of this type of pollution. The main objective of this work is to propose a reflection from the second law of thermodynamics that explains the mitigation of the impact of solid waste. From thermodynamics, a model for mitigating environmental impact is proposed, considering the dissipative structure as the model to generate the transformation from chaos to order. [ABSTRACT FROM AUTHOR]

Introduction. In Colombia during the last few years, recycling and environmental education have gained relevance. Educational campaigns have made visible the problem of not managing waste correctly and the effects caused by the lack of environmental education. Waste pickers have played a significant role in waste management, dedicating part of their time to training and educating others; however, there is still a lack of awareness in the communities about the social relevance of this profession. Objective. To understand the experiences of waste pickers and the impact of their trade on the communities' awareness of environmental care. Materials and methods. A qualitative study was conducted with the participation of eight waste pickers from the city of Cartagena. A semi-structured interview was used for data collection and the information was analyzed taking into account the grounded theory with the support of the NVivo program version 10.0. Results. Being a waste picker is considered a stable job and the main source of income; the participants express the support received from their families. For them, environmental education begins in homes and schools from childhood. Despite the improvement in the quality of life as a result of the profession, there are still social prejudices and little recognition. Conclusions. It is necessary to build an integral vision of the problem in which the government and different organizations participate in actions that promote environmental education. [ABSTRACT FROM AUTHOR]

The impact of inoculum (mature compost) was assessed in an aerobic system for the rapid degradation of organic solid waste, with a focus on the release of reducing sugars. Isothermal (35 and 55 °C) and non-isothermal (35-55°C) treatments were conducted. Key indicators, including the rate of oxygen consumption (O2) and carbon dioxide production (CO2), were measured to assess microbial activity. Additionally, the concentration of reducing sugars, pH, enzymatic activity, and the presence of pathogens were evaluated. Treatments with inoculum at 35 °C and without inoculum at 55°C exhibited an increase in oxygen consumption and CO2 production, indicating heightened microbial activity and, consequently, greater mineralization of organic matter. The treatment without inoculum at 35-55 °C presented the highest concentration of reducing sugars (160 mg/g dry weight), suggesting its potential as a pretreatment for bioconversion processes aimed at generating value-added products. At a temperature of 55°C, there was a reduction of 84.4, 87.28, and 67.33% in the concentrations of fecal coliforms, Escherichia coli, and parasites, respectively. This result suggests that elevated temperature contributes to the effectiveness of pathogen elimination. [ABSTRACT FROM AUTHOR]

Introduction: Craft beer production generates solid waste in significant quantities, which is not put to proper use. Trüb (brewers' waste) has important nutrients, such as proteins and carbohydrates, and physical-chemical compounds; however, its applications are hindered by its astringent taste. Objective: To estimate the enrichment of flour from malts processed in craft beer by addition of fermentable Trüb (sediment). Materials and Methods: The methodology applied was experimental, carrying out the physical-chemical characterization of processed samples of craft beer waste, evaluating moisture, ash, fat, acidity, protein, and fiber, based on the established standards. Results and Discussion: As a result, it was obtained that the best mixture of malt with sediment was the dark malt with kveik sediment with a proportion of 25 %, obtaining protein increase values of 26.73 %. Conclusions: With an increase in protein the best malt and sediment sample was the dark malt - sediment Kveik from 12.95 - 26.73 % w/w, without addition and addition to 25 % of the sediment. [ABSTRACT FROM AUTHOR]

Copyright of Acta Universitaria is the property of Universidad de Guanajuato/Acta Universitaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Universitaria is the property of Universidad de Guanajuato/Acta Universitaria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Novedades en Población is the property of Universidad de La Habana, Centro de Estudios Demograficos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of CienciAmérica is the property of Revista Cienciamerica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Extensão em Foco is the property of Universidade Federal do Parana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista U.D.C.A Actualidad & Divulgación Científica is the property of Universidad de Ciencias Aplicadas y Ambientales U.D.C.A and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeledonia is the property of Asociacion Ornitologica de Costa Rica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to analyze the most significant problems in relation to the landscape that were identified by the population of the island of Mexcaltitán, Nayarit, Mexico, during the period 2019-2022. Data was gathered through semistructured interviews during the period of 2019-2022 and using the phenomenological thematic analysis method. The main findings suggest that the most representative problems are solid waste pollution, local impacts from the island's infrastructure, and conflicts of interest with authorities related to tourism. [ABSTRACT FROM AUTHOR]

The problem of household solid waste management is a growing concern throughout the world due to the constant increase in the urban population and the generation of garbage. The purpose of this article is to analyze the amount of solid waste generated by homes, with the objective of evaluating the eco-efficient management of household solid waste for the sustainable development of the Quevedo Canton, Guayacán parish, seeking to promote an environmental culture and reduce the levels pollution caused by poor waste management. This was achieved through the proper management of organic and inorganic waste. Taking into consideration 116 households as a sample, implementing questionnaires based on the liker scale with a confidence level of 95% and a margin of error of 5% in a quantitative manner, where the daily generation will be 1.30 kg/hb/day. Once the results were obtained, we worked on the construction of the decision tree with the main purpose of identifying the characteristic with the greatest impact on each home by manipulating the Python programming language. In this sense, the eco-efficient management of household organic waste is presented as an alternative with a higher percentage promoting sustainable development where the importance in the social and economic development of households was highlighted by carrying out an updated diagnosis on the levels of knowledge and participation showing an average model accuracy of approximately 89.6%, based on the selected features. [ABSTRACT FROM AUTHOR]

Copyright of Revista Venezolana de Gerencia (RVG) is the property of Revista de Filosofia-Universidad del Zulia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Venezolana de Gerencia (RVG) is the property of Revista de Filosofia-Universidad del Zulia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Opuntia Brava is the property of Universidad de Ciencias Pedagogicas de Las Tunas, Centro de Documentacion e Informacion Pedagogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Opuntia Brava is the property of Universidad de Ciencias Pedagogicas de Las Tunas, Centro de Documentacion e Informacion Pedagogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Opuntia Brava is the property of Universidad de Ciencias Pedagogicas de Las Tunas, Centro de Documentacion e Informacion Pedagogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Opuntia Brava is the property of Universidad de Ciencias Pedagogicas de Las Tunas, Centro de Documentacion e Informacion Pedagogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Opuntia Brava is the property of Universidad de Ciencias Pedagogicas de Las Tunas, Centro de Documentacion e Informacion Pedagogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Opuntia Brava is the property of Universidad de Ciencias Pedagogicas de Las Tunas, Centro de Documentacion e Informacion Pedagogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Opuntia Brava is the property of Universidad de Ciencias Pedagogicas de Las Tunas, Centro de Documentacion e Informacion Pedagogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)