1,294 research outputs found
Modelo para la adopción del comercio electrónico en el sector agroindustrial mexicano
En este trabajo se propone un modelo para la adopción del comercio electrónico en las pequeñas y medianas empresas (pyme´s) del sector agroindustrial mexicano. El modelo final consta de dieciocho variables, distribuidas en siete submodelos, que son: Factores organizacionales, características técnicas, comunicación, factores ambientales, factores psicológicos y culturales, apoyo gubernamental y adopción del comercio electrónico. Para la medición de las variables se aplicó un cuestionario a las empresas de una muestra representativa. En la validación del modelo, se usó la técnica de mínimos cuadrados parciales (PLS). Se validó la consistencia interna del modelo mediante las pruebas de unidimensionalidad, fiabilidad, validez convergente y validez discriminante; así como la validación del modelo estructural
Beliefs and Attitudes Toward Intimate Partner Violence in a Group of Young Puerto Ricans
In this paper we aim to describe the beliefs and attitudes young people in Puerto Rico have toward intimate partner violence (IPV). Although Puerto Rico has a high rate of IPV, little empirical research has been conducted about the beliefs and attitudes people have regarding this issue. We conducted 20 in-depth qualitative interviews with young men and women. Data was analyzed using the qualitative content analysis approach. Participants expressed that men are more violent than women because of testosterone, machismo, and alcohol and other drug use. Both male and female participants stated that they believe they have the same rights to make decisions. Participants did not express directly stereotypical attitudes and beliefs that justify IPV. However, there remains a desire in some participants to have control over where their partner is and what he or she is doing. Preventive interventions are urgently needed to promote healthier relationships among young people
Image Analysis Assessment of the Shelf Life of Fresh Strawberries
Extending the shelf life of food products like strawberries (Fragaria ananassa) is one of Europe's main goals to improving food safety and reduce food waste. In this study, a model has been developed to estimate and predict the quality of strawberries. Strawberries appearance and colour parameters has been determined by image analysis and traditional methods. Pictures of strawberries stored at 5-35 ºC were taken daily for 15 days. In total, 48 images were recorded and analysed. The colour images (RGB images) were processed in the laboratory using a specific image acquisition and analysis program. A linear model has been developed with high accuracy (R2=0.83) to estimate appearance based only in image analysis. This approach allows the use of this technology in the food chain industry
Aportaciones en Ciencias Sociales: Economía y Humanidades
Lo que se presenta es resultado del apoyo y la colaboración de varias instituciones, grupos de investigadores e investigadores independientes. En ese sentido, queremos otorgar un reconocimiento a quienes tuvieron la voluntad y el tino de apoyar esta iniciativa. Agradecemos a las autoridades de la Universidad Autónoma Chapingo, particularmente a la Rectoría y a sus Direcciones Generales, en especial a la Dirección General de Investigación y Posgrado. Reconocemos también la contribución de la División de Ciencias Económico-Administrativas y de la Preparatoria Agrícola, ambas de esta universidad, pues su ayuda hizo posible este trabajo. Asimismo, expresamos una particular gratitud a las autoridades de la Universidad Autónoma del Estado de México, quiénes a través de directivos, docentes y trabajadores del Centro Universitario UAEM Texcoco, colaboraron de manera generosa. No menos importante fue el apoyo de autoridades y personal especializado del Instituto Nacional de Estadística y Geografía (INEGI). En ello incluimos también a la Facultad de Economía de la Universidad Nacional Autónoma de México, particularmente a la Facultad de Ciencias, así como al Colegio de Postgraduados
Nature-based solutions for flood mitigation and soil conservation in a steep-slope olive-orchard catchment (Arquillos, Spain)
The frequency and magnitude of flash floods in the olive orchards of southern Spain have increased because of climate change and unsustainable olive-growing techniques. Affected surfaces occupy >85%
of the rural regions of the Upper Guadalquivir Basin. Dangerous geomorphic processes record the increase of runoff, soil loss and streamflow through time. We report on ripple/dune growth over a plane bed on overland flows, deep incision of ephemeral gullies in olive groves and rock-bed erosion in streams, showing an extraordinary sediment transport capacity of sub-daily pluvial floods. We develop a novel method to design optimal solutions for natural flood management and erosion risk mitigation. We adopt physical-based equations and build a whole-system model that accurately reproduces the named processes. The approach yields the optimal targeted locations of nature-based solutions (NbSs) for active flow-control by choosing the physical-model parameters that minimise the peak discharge and the erosion-prone area, maximising the soil infiltration capacity. The sub-metric spatial resolution used to resolve microtopographic features of terrains/NbS yields a computational mesh with millions of cells, requiring a Graphics Processing Unit (GPU) to run massive numerical simulations. Our study could contribute to developing principles and standards for agricultural-management initiatives using NbSs in Mediterranean olive and vineyard orchards.This work was funded by: “Programa Operativo FEDER 2014-2020” and “Consejería de Economía y Conocimiento de la Junta de Andalucía” grant number 138096; the European Union NextGenerationEU/PRTR and MCIN/AEI/10.13039/501100011033 grant number TED2021-129910B-I00
Technological advances to rescue temporary and ephemeral wetlands: reducing their vulnerability, making them visible
Mediterranean temporary ponds are a priority habitat according to the Natura 2000 network of the European Union, and complete inventories of these ecosystems are therefore needed. Their small size, short hydroperiod, or severe disturbance make these ponds undetectable by most remote sensing systems. Here we show, for the first time, that the distributed hydrologic model IBER+ detects ephemeral and even extinct wetlands by fully exploiting the available digital elevation model and resolving many microtopographic features at drainage basin scales of about 1000 km2. This paper aims to implement a methodology for siting flood-prone areas that can potentially host a temporary wetland, validating the results with historical orthophotos and existing wetlands inventories. Our model succeeds in dryland endorheic catchments of the Upper Guadalquivir Basin: it has detected 89% of the previously catalogued wetlands and found four new unknown wetlands. In addition, we have found that 24% of the detected wetlands have disappeared because of global change. Subsequently, environmental managers could use the proposed methodology to locate wetlands quickly and cheaply. Finding wetlands would help monitor their conservation and restore them if needed.This work was funded by: “Programa Operativo FEDER 2014–2020” and “Consejería de Economía y Conocimiento de la Junta de Andalucía” grant number 138096; the European Union NextGenerationEU/PRTR and MCIN/AEI/10.13039/501100011033 grant number TED2021-129910BI00
Gene expression changes in mononuclear cells from patients with metabolic syndrome after acute intake of phenol-rich virgin olive oil
RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.Abstract Background Previous studies have shown that acute intake of high-phenol virgin olive oil reduces pro-inflammatory, pro-oxidant and pro-thrombotic markers compared with low phenols virgin olive oil, but it still remains unclear whether effects attributed to its phenolic fraction are exerted at transcriptional level in vivo. To achieve this goal, we aimed at identifying expression changes in genes which could be mediated by virgin olive oil phenol compounds in the human. Results Postprandial gene expression microarray analysis was performed on peripheral blood mononuclear cells during postprandial period. Two virgin olive oil-based breakfasts with high (398 ppm) and low (70 ppm) content of phenolic compounds were administered to 20 patients suffering from metabolic syndrome following a double-blinded, randomized, crossover design. To eliminate the potential effect that might exist in their usual dietary habits, all subjects followed a similar low-fat, carbohydrate rich diet during the study period. Microarray analysis identified 98 differentially expressed genes (79 underexpressed and 19 overexpressed) when comparing the intake of phenol-rich olive oil with low-phenol olive oil. Many of these genes seem linked to obesity, dyslipemia and type 2 diabetes mellitus. Among these, several genes seem involved in inflammatory processes mediated by transcription factor NF-κB, activator protein-1 transcription factor complex AP-1, cytokines, mitogen-activated protein kinases MAPKs or arachidonic acid pathways. Conclusion This study shows that intake of virgin olive oil based breakfast, which is rich in phenol compounds is able to repress in vivo expression of several pro-inflammatory genes, thereby switching activity of peripheral blood mononuclear cells to a less deleterious inflammatory profile. These results provide at least a partial molecular basis for reduced risk of cardiovascular disease observed in Mediterranean countries, where virgin olive oil represents a main source of dietary fat. Admittedly, other lifestyle factors are also likely to contribute to lowered risk of cardiovascular disease in this region.Published versio
Potential protective role of reactive astrocytes in the periventricular parenchyma in congenital hydrocephalus
Background
Cerebrospinal fluid accumulation in hydrocephalus produces an elevation of intraventricular pressure with pathological consequences on the periventricular brain parenchyma including ischemia, oedema, oxidative stress, and accumulation of metabolic waste products. Here we studied in the hyh mouse, an animal model of congenital hydrocephalus, the role of reactive astrocytes in this clinical degenerative condition.
Materials and Methods
Wild type and hydrocephalic hyh mice at 30 days of postnatal age were used. Three metabolites related to the oxidative and neurotoxic conditions were analysed in ex vivo samples (glutathione, glutamine and taurine) using High Resolution Magic Angle Spinning (HR-MAS). Glutathione synthetase and peroxidase, glutamine synthetase, kidney-type glutaminase (KGA), and taurine/taurine transporter were immunolocated in brain sections.
Results
Levels of the metabolites were remarkably higher in hydrocephalic conditions. Glutathione peroxidase and synthetase were both detected in the periventricular reactive astrocytes and neurons. Taurine was mostly found free in the periventricular parenchyma and in the reactive astrocytes, and the taurine transporter was mainly present in the neurons located in such regions. Glutamine synthetase was found in reactive astrocytes. Glutaminase was also detected in the reactive astrocytes and in periventricular neurons. These results suggest a possible protective response of reactive astrocytes against oxidative stress and neurotoxic conditions.
Conclusions
Astrocyte reaction seems to trigger an anti-oxidative and anti-neurotoxic response in order to ameliorate pathological damage in periventricular areas of the hydrocephalic mice.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. PI15-00619 to AJJ
INVESTIGACIÓN EN QUÍMICA, BIOLOGÍA Y AGRONOMÍA
Este libro es el segundo de una serie de dos dedicado a los avances lo relativo a las mezclas de diesel y biodiesel obtenido a partir del aceite de semillas de jatropha curcas, entre otros temas de ese ombustible verde; es decir algo que está al día en cuanto a las búsqueda de fuentes de energía limpias; otro tema ampliamente tratado es el del nitrógeno como elemento de fertilización -que junto con la densidad poblacional de las plantas- buscan prácticas agronómicas para obtener mayores rendimientos. El objetivo final de este libro es el mismo: incorporar cada vez más bibliografía que enriquezca las opciones de consulta por parte de interesados en aspectos particulares y, desde luego, divulgar nuevos conocimentos y ofrecer los resultados del quehacer universitario
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