Renewable energy research progress in Mexico: a review

Mexico ranks 9th in the world in crude oil reserves, 4th in natural gas reserves in America and it is also highly rich in renewable energy sources (solar, wind, biomasss, hydropower and geothermal). However, the potential of this type of energy has not been fully exploited. Hydropower is the renewable energy source with the highest installed capacity within the country (11,603 MW), while geothermal power capacity (958 MW) makes Mexico to be ranked 4th in the use of this energy worldwide. Wind energy potential is concentrated in five different zones, mainly in the state of Oaxaca, and solar energy has a high potential due to Mexico's ideal location in the so called Solar Belt. Biomass energy has the highest potential (2635 to 3771 PJ/year) and has been the subject of the highest number of research publications in the country during the last 30 years (1982-2012). Universidad Nacional Autonoma de Mexico has led research publications in hydropower, wind, solar and biomass energy and Instituto de Investigaciones Electricas in geothermal energy during this period. According to the General Law for Climate Change the country has set the goal of generating 35% of its energy needs from renewable sources by 2024. This paper presents an overview of the renewable energy options available in Mexico, current status, main positive results to date and future potential. It also analyses barriers hindering improvements and proposes pertinent solutions. © 2014 The Authors

Randomized double blind crossover trial of Aloe vera , Cnidoscolus chayamansa and placebo for reducing hyperglycemia in women with early metabolic syndrome

Background: There have been antidiabetic claims for Aloe vera (AG) Barbadensis Mill. gel and infusion of Cnidoscolus chayamansa (CC) McVaugh. Objectives: To determine if the ingestion of total process AG concentrated 5:1 (TA), AG, CC or placebo can reduce hyperglycemia in women with early metabolic syndrome (EMS). Methods: One hundred-twenty five women from two outpatient university clinics were randomly assigned to a three assay doubleblind crossover procedure. Subjects were adult women with EMS by ATP III criteria assigned to assay 1: AG&CC vs P1&P2; assay 2: AG&P2 vs P1&CC; or assay 3: TA vs P3. All assays included the ingestion of one, then zero (washout period), then two gelatins/day, for 4, 1, 4 weeks, respectively. The expected outcome was an HbA1c decrease ≥4.2 mmol/mol or lower but sustaining euglycemia. Results: Participants had a mean age of 46.8 ± 9.7 years and a mean HbA1c of 47.8 ± 12.7 mmol/mol at the start of the study. The least tolerated combination was AG&P2. Patients complained of bad taste and mild stomach pain because of the double dose of this treatment; this caused withdrawals: 4/25 vs. 9/21, respectively, Chi square ¼ 4.1, df ¼ 1, P 0.05; assay 2, 1.3 ± 6.6 vs 1.4 ± 7.6, P > 0.05; assay 3, 4.9 ± 8.3 vs 0.44 ± 5.4, P < 0.01, respectively. TA concomitantly reduced high-sensitive C-reactive protein (hs-CRP) (P < 0.05). Conclusions: Data suggest that TA decreases blood glucose levels by reducing the proinflammatory state. The infusion of microwave dehydrated CC leaves did not reduce blood glucose or HDL and triglyceride levels

Growth and yield models for black beans under magnetization and pH variation in a greenhouse

Objective: To estimate growth and yield variations in common beans (Phaseolus vulgaris L.) treated with a magnetized nutrient solution considering two factors: magnet exposure time and pH level. The significance of this crop lies in its nutritional and economic value. Design/Methodology/Approach: We used a hydroponic system with magnetized Steiner nutrient solution. The design was completely randomized, with a 4 x 6 factorial treatment arrangement and three replications. Factor A comprised exposure times (0.333 hours, 2 hours, chronic, and without magnetization), while Factor B covered solutions with different pH levels (3, 4, 5, 6, 7, and 8). We then applied a multiple regression analysis using the SAS software. &nbsp; Results: Models for vegetative growth variables (plant height, root length, root dry weight, and foliar biomass) and seed yield components (number of pods, number of grains per pod) were statistically significant (p&lt;0.0001). Coefficients of determination ranged from 59.7 % to 82 %, percentages considered appropriate to explain the observed variability. Study limitations/Implications: While the models showed acceptable coefficients of determination, it is essential to consider other factors that were not assessed in this study: exposure to sunlight, insect influence, and diseases that could impact the responses of the bean crop. Findings/Conclusions: Appropriate models to describe vegetative growth and seed yield of the common bean, concerning magnetization time and nutrient solution acidity, include variables such as plant height, root length, root dry weight, foliar biomass, total biomass, number of pods, and number of grains per pod

Electrocatalytic urea mineralization in aqueous alkaline medium using NiIIcyclam-modified nanoparticulate TiO2 anodes and its relationship with the simultaneous electrogeneration of H2 on Pt counterelectrodes

NiIIcyclam-modified nanoparticulate TiO2-coated ITO electrodes (ITO/TiO2//NiIIcyclam) were prepared by electropolymerization of NiIIcyclam monomers to TiO2-coated ITO electrodes (ITO/TiO2) to improve electrocatalytic urea CO(NH2)2 oxidation in alkaline aqueous solutions. A high value adding secondary effect was the collection of electrons at Pt cathodes, to simultaneously generate H2 from water reduction. NiIIcyclam-modified ITO electrodes (ITO//NiIIcyclam) were also prepared by electropolymerization of NiIIcyclam monomers to bare ITO electrodes (ITO) for comparison purposes. In the presence of the TiO2 nanoparticles, the urea mineralization on NiIIcyclam coatings was doubled (23.95% – organic carbon removal at 120 min of electrolysis) compared to those without TiO2 nanoparticles (13.02% – organic carbon removal at 120 min of electrolysis). In agreement, the faradaic efficiency for H2 generation at the Pt cathode, electrically connected to an anode having TiO2 nanoparticles (0.99 at 120 min of electrolysis), was also twice as effective than that observed when the same Pt cathode was electrically connected to an anode without TiO2 nanoparticles (0.46 at 120 min of electrolysis). The experimental results indicated that the poisoning of NiII centers (which is caused by an excessive production of CO intermediates during the urea oxidation on both NiIIcyclam-modified anodes) was strongly inhibited in the presence of the nanoparticulate TiO2|NiIIcyclam junction. A final comparison between our results and those reported in selected publications revealed that the NiIIcyclam-modified nanoparticulate TiO2-coated ITO anodes here developed, constitutes a promising electrocatalytic system for performing direct urea mineralization at a relative short electrolysis time. Furthermore, the combination of the following phenomena: (a) effective charge separation on the semiconducting ITO|nanoparticulate TiO2 junctions, (b) remarkable capabilities of the nanoporous TiO2 films for tuning the load of OH� anions demanded by the urea oxidation and, (c) outstanding capabilities of the TiO2 nanoparticles for capturing CO intermediates (at Ti3+ donor sites), successfully promoted the enhancement of the electron external transport to Pt cathodes, and consequently improved the faradaic efficiency associated to the cathodic generation of H2

Estrategia de evaluación financiera en la MiPyme para la toma de decisiones sobre adopción tecnológica :giro alimentos procesados

Ingenierí

Application of microbial electrolysis cells to treat spent yeast from an alcoholic fermentation

Spent yeast (SY), a major challenge for the brewing industry, was treated using a microbial electrolysis cell to recover energy. Concentrations of SY from bench alcoholic fermentation and ethanol were tested, ranging from 750 to 1500mgCOD/L and 0 to 2400mgCOD/L respectively. COD removal efficiency (RE), coulombic efficiency (CE), coulombic recovery (CR), hydrogen production and current density were evaluated. The best treatment condition was 750mgCOD/LSY+1200mgCOD/L ethanol giving higher COD RE, CE, CR (90±1%, 90±2% and 81±1% respectively), as compared with 1500mgCOD/LSY (76±2%, 63±7% and 48±4% respectively); ethanol addition was significantly favorable (p value=0.011), possibly due to electron availability and SY autolysis. 1500mgCOD/LSY+1200mgCOD/L ethanol achieved higher current density (222.0±31.3A/m3) and hydrogen production (2.18±0.66 LH2/day/LReactor) but with lower efficiencies (87±2% COD RE, 71.0±.4% CE). Future work should focus on electron sinks, acclimation and optimizing SY breakdown. © 2015 The Authors. Published by Elsevier Ltd

Processus de légitimation discursive entre la médecine allopathique et la médicine traditionnelle : le cas de la langue Tlahuica dans l’État du Mexique

The article addresses processes of discursive legitimation of traditional and allopathic medicine practices from a linguistic anthropology framework. The main purpose of the study is to identify the rationale underlying these two modes of human experience: The objective-intellectual and the subjective-affective. This, with the aims of 1) re-evaluating traditional medicine through the reconstruction of its legitimation processes, 2) revitalizing knowledge associated with traditional medicine in Mexico. In methodological terms, the study involves a semiotic analysis based on the theory of the production of signs, and a comparison of the structure and the relational systems of both logical and social codes. Results show that by tracing the legitimation processes of traditional medicine, groups in the process of recovering ancestral practices gain visibility which, in turn, works as support to highlight the need of revitalization and maintenance of Mexican indigenous languages.El artículo contiene un abordaje sobre los procesos de legitimación discursiva entre las prácticas de medicina tradicional y las prácticas alópatas desde la antropología lingüística. El objetivo central consiste en identificar la racionalidad entre estos dos modos de la experiencia humana: la objetiva-intelectiva y la subjetiva-afectiva. Los objetivos específicos son:1) la revaloración de la medicina tradicional a través de la reconstrucción del proceso de legitimación, 2) la recuperación del saber asociado con la medicina tradicional en México. La metodología corresponde a un análisis semiótico desde la teoría de la producción de los signos y se hace una comparación entre la estructura y los sistemas de relaciones de ambos códigos lógicos y sociales. Como resultados de la investigación se destacan: la documentación sobre los procesos de legitimación de la medicina tradicional, se visibilizan grupos en proceso de recuperación de prácticas ancestrales y se propone la revitalización y el mantenimiento de lenguas indígenas en México.The article addresses processes of discursive legitimation of traditional and allopathic medicine practices from a linguistic anthropology framework. The main purpose of the study is to identify the rationale underlying these two modes of human experience: The objective-intellectual and the subjective-affective. This, with the aims of 1) re-evaluating traditional medicine through the reconstruction of its legitimation processes, 2) revitalizing knowledge associated with traditional medicine in Mexico. In methodological terms, the study involves a semiotic analysis based on the theory of the production of signs, and a comparison of the structure and the relational systems of both logical and social codes. Results show that by tracing the legitimation processes of traditional medicine, groups in the process of recovering ancestral practices gain visibility which, in turn, works as support to highlight the need of revitalization and maintenance of Mexican indigenous languages

Renewable energy research progress in Mexico: A review

Mexico ranks 9th in the world in crude oil reserves, 4th in natural gas reserves in America and it is also highly rich in renewable energy sources (solar, wind, biomasss, hydropower and geothermal). However, the potential of this type of energy has not been fully exploited. Hydropower is the renewable energy source with the highest installed capacity within the country (11,603 MW), while geothermal power capacity (958 MW) makes Mexico to be ranked 4th in the use of this energy worldwide. Wind energy potential is concentrated in five different zones, mainly in the state of Oaxaca, and solar energy has a high potential due to Mexico's ideal location in the so called Solar Belt. Biomass energy has the highest potential (2635 to 3771 PJ/year) and has been the subject of the highest number of research publications in the country during the last 30 years (1982-2012). Universidad Nacional Autonoma de Mexico has led research publications in hydropower, wind, solar and biomass energy and Instituto de Investigaciones Electricas in geothermal energy during this period. According to the General Law for Climate Change the country has set the goal of generating 35% of its energy needs from renewable sources by 2024. This paper presents an overview of the renewable energy options available in Mexico, current status, main positive results to date and future potential. It also analyses barriers hindering improvements and proposes pertinent solutions. © 2014 The Authors