Las organizaciones no gubernamentales y la sostenibilidad de las pequeñas y medianas empresas en el Perú: un análisis de redes y discursos

El análisis a profundidad de las redes internacionales de ONG que operan en el Perú propician valiosas evidencias de los cambios en los patrones de las redes y discursos, y consecuentemente, en el cambio de las reglas de las ONGs. De manera contundente, los discursos de los movimientos sociales, el libre mercado y la sostenibilidad están generando nuevas redes y discursos con posiciones de poder de las ONGs nacionales e internacionales en relación a las PYMES. El análisis discrepa con la teoría de castells del “espacio de los flujos” frente al “espacio de los lugares”, y sugiere considerar en la teoría de la modernización ecológica tanto la racionalidad ecológica y la racionalidad social con el fin de hacer notable la gobernanza ambiental en los países desarrollados, particularmente en América Latina.Ford Foundation International Fellowsships Programk (IFP)Tesi

Cellulose pretreatment and dissolution: Selection of solvent and processing conditions

Efficient utilization of biomass is hindered by the recalcitrance to dissolution of semicrystalline cellulose. Pretreatment is often used to alter the structure of cellulosic biomass in order to make cellulose more accessible to solvents and enzymes. The pretreatment involves physical and/or chemical processing which affects the degree of crystallinity and size of biomass particles. We examine here the effects of (i) solvent properties, pretreatment steps and temperature, and (ii) fiber diameter and degree of crystallinity, on the kinetics of cellulose swelling and dissolution. To this end we have combined (a) experimental results on cotton fiber swelling, change in crystallinity and dissolved amount when treated under different solvent conditions, with (b) a phenomenological model that accounts for the phenomena governing the dissolution of solid cellulose, e.g., solvent penetration, transformation from crystalline to amorphous domains, specimen swelling, and polymer chain untangling [1]. The insights obtained from this analysis would facilitate the rational selection of solvents and the design of pretreatment processes to reduce the size and degree of crystallinity of cellulosic biomass particles, leading to enhanced biomass utilization [2]. References: [1] Ghasemi, M.; Singapati, A. Y.; Tsianou, M.; Alexandridis, P., Dissolution of semicrystalline polymer fibers: Numerical modeling and parametric analysis. AIChE Journal 2017, 63 (4), 1368-1383. DOI: 10.1002/aic.15615. [2] Ghasemi, M.; Tsianou, M.; Alexandridis, P., Assessment of solvents for cellulose dissolution. Bioresource Technol. 2017, 228, 330-338. DOI: 10.1016/j.biortech.2016.12.049

Properties of small molecular drug loading and diffusion in a fluorinated PEG hydrogel studied by ¹H molecular diffusion NMR and ¹⁹F spin diffusion NMR

R_f-PEG (fluoroalkyl double-ended poly(ethylene glycol)) hydrogel is potentially useful as a drug delivery depot due to its advanced properties of sol–gel two-phase coexistence and low surface erosion. In this study, ¹H molecular diffusion nuclear magnetic resonance (NMR) and ¹⁹F spin diffusion NMR were used to probe the drug loading and diffusion properties of the R_f-PEG hydrogel for small anticancer drugs, 5-fluorouracil (FU) and its hydrophobic analog, 1,3-dimethyl-5-fluorouracil (DMFU). It was found that FU has a larger apparent diffusion coefficient than that of DMFU, and the diffusion of the latter was more hindered. The result of ¹⁹F spin diffusion NMR for the corresponding freeze-dried samples indicates that a larger portion of DMFU resided in the R_f core/IPDU intermediate-layer region (where IPDU refers to isophorone diurethane, as a linker to interconnect the R_f group and the PEG chain) than that of FU while the opposite is true in the PEG–water phase. To understand the experimental data, a diffusion model was proposed to include: (1) hindered diffusion of the drug molecules in the R_f core/IPDU-intermediate-layer region; (2) relatively free diffusion of the drug molecules in the PEG-water phase (or region); and (3) diffusive exchange of the probe molecules between the above two regions. This study also shows that molecular diffusion NMR combined with spin diffusion NMR is useful in studying the drug loading and diffusion properties in hydrogels for the purpose of drug delivery applications

Cellulose pretreatment and dissolution: Selection of solvent and processing conditions

Efficient utilization of biomass is hindered by the recalcitrance to dissolution of semicrystalline cellulose. Pretreatment is often used to alter the structure of cellulosic biomass in order to make cellulose more accessible to solvents and enzymes. The pretreatment involves physical and/or chemical processing which affects the degree of crystallinity and size of biomass particles. We examine here the effects of (i) solvent properties, pretreatment steps and temperature, and (ii) fiber diameter and degree of crystallinity, on the kinetics of cellulose swelling and dissolution. To this end we have combined (a) experimental results on cotton fiber swelling, change in crystallinity and dissolved amount when treated under different solvent conditions, with (b) a phenomenological model that accounts for the phenomena governing the dissolution of solid cellulose, e.g., solvent penetration, transformation from crystalline to amorphous domains, specimen swelling, and polymer chain untangling [1]. The insights obtained from this analysis would facilitate the rational selection of solvents and the design of pretreatment processes to reduce the size and degree of crystallinity of cellulosic biomass particles, leading to enhanced biomass utilization [2]. References: [1] Ghasemi, M.; Singapati, A. Y.; Tsianou, M.; Alexandridis, P., Dissolution of semicrystalline polymer fibers: Numerical modeling and parametric analysis. AIChE Journal 2017, 63 (4), 1368-1383. DOI: 10.1002/aic.15615. [2] Ghasemi, M.; Tsianou, M.; Alexandridis, P., Assessment of solvents for cellulose dissolution. Bioresource Technol. 2017, 228, 330-338. DOI: 10.1016/j.biortech.2016.12.049

Lactic acid bacteria occurring during manufacture and ripening of Provolone del Monaco cheese: detection by different analytical approaches

Lactic acid bacteria occurring in Provolone del Monaco, an artisanal pasta filata cheese produced in Campania (Italy) from raw cows’ milk and without starter addition, were investigated by a combination of conventional and molecular approaches. The microbial community was monitored during a cheese-making process giving rise to a premium quality product. Streptococcus thermophilus and Streptococcus macedonicus prevailed during cheese manufacture and survived along nine months of ripening, together with enterococci and lactobacilli of the casei group, especially Lactobacillus rhamnosus. Phenotypic and genetic identification of 308 isolates largely reflected the results obtained by 16S rDNA sequencing analysis by polymerase chain reaction-denaturant gradient gel electrophoresis, with the significant exception of Lactobacillus fermentum and four Lactobacillus delbrueckii subspecies that were not detected by cultural methods. Each different analytical approach employed provided useful information. Their combination proved to be suitable to effectively describe the ecosystem of Provolone del Monaco cheese

Interacciones árbol-suelo y funcionamiento del bosque mediterránao: síntesis del proyecto INTERBOS

1 página. Comunicación oral presentada en la Sesión Ecología y Ecofisiología de la referida Reunión, celebrada en Huelva, 9-11, noviembre, 2011.Se conoce como cambio global al conjunto de los cambios ambientales afectados por la actividad humana, con especial referencia a cambios en los procesos que determinan el funcionamiento del sistema Tierra. El cambio global afecta al árbol individual, a su fisiología, crecimiento y composición de sus tejidos, ya su adecuación evolutiva respecto a los individuos vecinos de la misma población. Estos cambios afectan a su vez a las interacciones entre los árboles de las diferentes especies y causan cambios en el ensamblaje de la comunidad y la composición del bosque. En último término, modifican el funcionamiento del ecosistema forestal afectando a la fijación y secuestro del carbono, las tasas de descomposición de la hojarasca y el ciclo de nutrientes.Peer reviewe

Directed paths on hierarchical lattices with random sign weights

We study sums of directed paths on a hierarchical lattice where each bond has either a positive or negative sign with a probability $p$. Such path sums $J$ have been used to model interference effects by hopping electrons in the strongly localized regime. The advantage of hierarchical lattices is that they include path crossings, ignored by mean field approaches, while still permitting analytical treatment. Here, we perform a scaling analysis of the controversial ``sign transition'' using Monte Carlo sampling, and conclude that the transition exists and is second order. Furthermore, we make use of exact moment recursion relations to find that the moments always determine, uniquely, the probability distribution $P(J)$. We also derive, exactly, the moment behavior as a function of $p$ in the thermodynamic limit. Extrapolations ($n\to 0$) to obtain for odd and even moments yield a new signal for the transition that coincides with Monte Carlo simulations. Analysis of high moments yield interesting ``solitonic'' structures that propagate as a function of $p$. Finally, we derive the exact probability distribution for path sums $J$ up to length L=64 for all sign probabilities.Comment: 20 pages, 12 figure

Factores predisponentes a la parvovirosis canina registrados en un hospital de Cuautitlan, México

Canine parvovirus (CPV) was initially described in the Canidae family, but later extended to Ursidae, Procionidae, and Felidae families, among others. Its epidemiology has not been fully described. Nevertheless, climate appears to have a direct influence on the severity of the disease symptomatology. Aim of this study was to analyze the influence of different factors such as age, breed, gender, vaccination status, and climatic variables, by means of analyzing cases of this disease recorded at an veterinary hospital from Cuautitlan (México). For this purpose, clinic histories from 2016 until 2017, were analyzed. Prevalence of 1.86% was determined, being animals under seven months-old those with the highest susceptibility to CPV. In addition, from March to May, the highest number of cases were diagnosed, with peak on April. The environmental temperature explains the higher presentation of cases of parvovirus. Considering these results, it can be concluded that CPV seems to be more frequent during the warmer months, followed by high number of offspring and lower consumption of food.El parvovirus canino (PVC) se restringió inicialmente a infectar a los perros, pero luego seextendió a otras familias como felidae (gatos y otros felinos), procionidae (mapaches, coatíes)y ursidae (osos). A pesar de que su epidemiología no ha sido descrita completamente,el clima parece tener influencia directa en los rangos de presentación. En este trabajo secompararon factores como edad, raza, género, estado vacunal y variables climáticas, conla aparición de la enfermedad en un hospital veterinario de Cuautitlan (México). Mediantela revisión de 3.862 historias clínicas de los años 2016-2017, se encontró una prevalencia de1,86% (72 animales) diagnosticados con PVC, siendo los menores de 7 meses los de mayorsusceptibilidad, especialmente durante los meses de marzo a mayo, con mayor incidencia enabril. La variable aumento de la temperatura ambiental explicó la mayor presentación de laenfermedad, seguida por el sexo hembra, el mayor número de crías, la joven edad y el menorconsumo de alimento

Diversity in Honors: Understanding Systemic Biases through Student Narratives

Centered on superiority over a certain group or individual, discrimination becomes predominant in prestigious institutions that pride themselves on exclusivity. Collegiate honors programs tend to deepen this practice by creating highly elite spaces accessible only to a select few. This rigidity can lead to an underrepresentation of historically marginalized groups, students who often lack the necessary resources for achieving academic excellence. This case study examines the ways honors programs inadvertently perpetuate discrimination among different social identities. Using inductive interviewing of honors students (n = 12) to gauge individual perceptions of program diversity, researchers rely on content analysis to generate four themes (relationship, discrimination, exclusion, conformity). By cross-analyzing participant responses with social identities, key programmatic components that may have led to covert systemic bias are uncovered. Results further indicate a possible link between a student’s racial identity and their sense of belonging within the program, with people of color reporting more instances of “othering” and discrimination. This study reveals a pressing need for increasing access to honors for minority students and improving the level of integration and retention among students currently enrolled