8 research outputs found

    Thematic analysis of the Excel Pre-Collegiate Program as an avenue of successful postsecondary enrollment for Latina/o students, A

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    2017 Summer.Includes bibliographical references.College access and college enrollment rates are significantly lower for students of color, students from lower socioeconomic backgrounds, and first-generation students (Reese, 2008). High schools, universities, and state and federal agencies have all recognized that the gap in college enrollment between students of color and their white counterparts is a major issue (Loza, 2003). High schools have implemented college prep classes and dual enrollment programs, universities have built bridge and pre-college programs, and the federal government has implemented legislation and provided funding geared at closing the enrollment gap between students of color and white students (Reese, 2008). Even with the various forms of interventions, the issue of low post-secondary enrollment specific to students of color continues. This study examines the experiences of Latina/o students who participated in the Excel Pre-Collegiate Program, a pre-college program offered through Metropolitan State University of Denver. In addition, the study explored how the participants' culture and background influenced their college-going and general educational experience. The study found that pre-college programs are an important and needed opportunity for students to gain the skills and knowledge to successfully navigate the college application process and enroll in college. Pre-college programs address many of the barriers and challenges that deter Latina/o students and students of color in general from attending higher education institutions

    Starch Modified With Chitosan and Reinforced With Feather Keratin Materials Produced by Extrusion Process: An Alternative to Starch Polymers

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    They also reached up to 3800% and 3150% in maximum strength, respectively, compared to the matrix. The lysozyme test showed relevant changes in the degradability rate, because the weight loss of the films at 3 weeks decreased from 53% for starch-chitosan matrix and up to 34% for composites with 5wt% of modified quill. The results corroborated that chicken feather materials can be useful for the development of a manufacturing process for starch composites, and the decomposition of starch-chitosan composites can be controlled depending on the content and type of keratin.Starch (potato), chitosan, and feather keratin are used for processing biodegradable films produced by extrusion. The morphology of the films is examined with a scanning electron microscope and showed the excellent dispersion of keratin. The dispersion is the result of compatibility between the polysaccharides and proteins, as well as the proper operation of the extrusion process. Water solubility of the starch-chitosan films decreased with an increase of keratin materials. The storage modulus increased up to 137% for the composites with unmodified ground quill, and by 192% for composites with modified ground quill. In a tensile test, the composites with unmodified and modified quill reached outstanding increments up to 8160 and 7250% in elastic modulus, respectively, compared to the matrixUniversidad Autonoma del Estado de Mexico Tecnologico Nacional de Mexico Universidad Nacional Autonoma de Mexico Universidad Autonoma de Cd. Juare

    Potential use of pruning-residues from avocado trees as energy input in rural communities

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    The global need to transition to renewable and decentralized systems entails agricultural systems as producers of residual biomass. Avocado trees (Persea americana Mill.) are one of the main woody crops cultivated in Mexico, with over 150,000 hectares grown in the country. The aim of the present study is to evaluate the use of avocado pruning residues as an energy input, focusing on the revalorization of biomass and the generation of economic benefits for small producers in the region. For that purpose, we developed allometric equations to calculate biomass availability from pruning residues, evaluated their thermochemical properties, and proposed technological alternatives for their energy use. Two allometric equations for pruning residues as a function of tree height and crown diameter were obtained: one for light and minor maintenance pruning (R2 = 0.63) and one for rejuvenation pruning (R2 = 0.86). From these equations, we estimate the mean amount of biomass generated from light and rejuvenation pruning to be 42.7 and 25.1 kg per tree and year, respectively, which amounts to 1324 and 780 kg ha−1 DM (dry matter), with an energy potential of 26.2 and 15.4 GJ ha−1. The thermochemical analysis shows that a higher proportion of leaves generates a higher ash content, which reduces the quality of the residues as a fuel. Avocado pruning residues have high potential for energy use and could be implemented in the industrial and residential sectors, generating a complementary source of income for producers.Fil: Tauro, Raúl. Universidad Nacional Autónoma de México; MéxicoFil: Velázquez Martí, Borja. Universidad Politécnica de Valencia; EspañaFil: Manrique, Silvina Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Ricker, Martín. Universidad Nacional Autonoma de Mexico. Facultad de Ciencias; MéxicoFil: Martínez Bravo, René. Universidad Nacional Autónoma de México; MéxicoFil: Ruiz García, Víctor. Universidad Nacional Autónoma de México; MéxicoFil: Ramos Vargas, Saraí. Universidad Nacional Autónoma de México; MéxicoFil: Masera, Omar Raul. Universidad Nacional Autónoma de México; MéxicoFil: Soria González, José A.. Universidad Michoacana de San Nicolás de Hidalgo. Facultad de Ingeniería en Tecnología de la Madera; MéxicoFil: Armendariz, Cynthia. Universidad Nacional Autónoma de México; Méxic

    Chitosan–Starch–Keratin composites: Improving thermo-mechanical and degradation properties through chemical modification

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    The lysozyme test shows an improved in the degradability rate, the weight loss of the films at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all films show a biodegradable character depending on keratin type and chemical modification. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosan–starch films with sustainable featuresChitosan–starch polymers are reinforced with different keratin materials obtained from chicken feather. Keratin materials are treated with sodium hydroxide; the modified surfaces are rougher in comparison with untreated surfaces, observed by Scanning Electron Microscopy. The results obtained by Differential Scanning Calorimetry show an increase in the endothermic peak related to water evaporation of the films from 92 °C (matrix) up to 102–114 °C (reinforced composites). Glass transition temperature increases from 126 °C in the polymer matrix up to 170–200 °C for the composites. Additionally, the storage modulus in the composites is enhanced up to 1614 % for the composites with modified ground quill, 2522 % for composites with modified long fiber and 3206 % for the composites with modified short fiber. The lysozyme test shows an improved in the degradability rate, the weight loss of the films at 21 days is reduced from 73 % for chitosan-starch matrix up to 16 % for the composites with 5wt% of quill; but all films show a biodegradable character depending on keratin type and chemical modification. The outstanding properties related to the addition of treated keratin materials show that these natural composites are a remarkable alternative to potentiat-ing chitosan–starch films with sustainable featuresUniversidad Autónoma del Estado de México Tecnológico Nacional de México, Instituto Tecnológico de Querétaro Universidad Nacional Autónoma de México Tecnológico Nacional de México, Instituto Tecnológico de Celaya Universidad Autónoma de Cd. Juáre

    Beyond fuelwood savings: Valuing the economic benefits of introducing improved biomass cookstoves in the Purépecha region of Mexico

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    Half of the world population relies on biomass for cooking, with very significant health as well as climate change impacts. Improved cookstoves have been disseminated as an alternative to reduce these impacts. However, few detailed studies about the economic benefits of improved cookstoves (ICS) interventions, including environmental and health co-benefits, exist to date. In this paper we perform a comprehensive economic evaluation of a dissemination program of ICS in rural Mexico. The resulting cost-benefit analysis (CBA) of the Patsari improved cookstove is presented, utilizing estimation of direct costs and benefits, including fuelwood savings, income generation, health impacts, environmental conservation, and reduction in greenhouse gas emissions. The analysis is based on comprehensive data obtained through monitoring studies carried out in the Study Area from 2003 to the present. Results show that Patsari cookstoves represent a viable economic option for improving living conditions of the poorest inhabitants of rural Mexico, with benefit/cost ratios estimated between 11.4:1 and 9:1. The largest contributors to economic benefits stemmed from fuelwood savings and reductions in health impacts, which constituted 53% and 28% of the overall benefit, respectively.Cost-benefit analysis Fuelwood Improved biomass cookstoves Carbon savings Mexico

    Effect of Prolonged-Release Pirfenidone on Renal Function in Septic Acute Kidney Injury Patients: A Double-Blind Placebo-Controlled Clinical Trial

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    Background. There is no treatment for septic acute kidney injury (sAKI). The anti-inflammatory activity of prolonged-release pirfenidone (PR-PFD) could be beneficial in this clinical setting. Methods. This study was a double-blind randomized clinical trial in sAKI patients with nephrology consultation at the Civil Hospital of Guadalajara, in addition to the usual treatment of AKI associated with sepsis; patients were randomized to receive either PR-PFD at 1,200 mg/day (group A) or 600 mg/day (group B) or a matched placebo for 7 consecutive days. The primary objective was the decrease in serum creatinine (sCr) and increase in urinary volume (UV); the secondary objectives were changes in serum electrolytes, acid-base status, and mortality. Results. Between August 2016 and August 2017, 88 patients were randomized. The mean age was 54 (17 ± SD) years, and 47% were male. The main site of infection was the lung (39.8%), septic shock was present in 39.1% of the cases, and the mean SOFA score was 8.8 points. 28 patients received PFD 1,200 mg, 30 patients received PFD 600 mg, and 30 patients received placebo. During the study, sCr did not differ among the groups. The reversion rate of sCr, UV, and mortality was not different among the groups (p=0.70, p=0.47, and p=0.38, respectively). Mild adverse events were not different among the groups. Conclusion. PR-PFD did not improve the clinical course of sAKI and seemed to be safe in terms of adverse events. This trial is registered with NCT02530359
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