567 research outputs found

    A probabilistic model for crystal growth applied to protein deposition at the microscale

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    A probabilistic discrete model for 2D protein crystal growth is presented. This model takes into account the available space and can describe growing processes of different nature due to the versatility of its parameters which gives the model great flexibility. The accuracy of the simulation is tested against a real protein (SbpA) crystallization experiment showing high agreement between the proposed model and the actual images of the nucleation process. Finally, it is also discussed how the regularity of the interface (i.e. the curve that separates the crystal from the substrate) affects to the evolution of the simulation.Comment: 13 pages, 12 figure

    Development and validation of the Spanish hazard perception test

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    Objective: The aim of the current study is to develop and obtain validity evidence for a Hazard Perception test suitable for the Spanish driving population. To obtain validity evidence to support the use of the test, the effect of hazardous and quasi-hazardous situations on the participants’ Hazard Prediction is analysed and the pattern of results of drivers of different driving experience: learner, novice and expert drivers and re-offender vs. non-offender drivers, is compared. Potentially hazardous situations are those that develop without involving any real hazard (i.e., the driver didn’t actually have to decelerate or make any evasive manoeuvre to avoid a potential collision). The current study analysed multiple offender drivers attending compulsory re-education programmes as a result of reaching the maximum number of penalty points on their driving licence, due to repeated violations of traffic laws. Method: A new video-based hazard perception test was developed, using a total of 20 hazardous situation videos plus 8 quasi-hazardous situation videos. They were selected from 167 recordings of natural hazards in real Spanish driving settings

    The absorption laws for the generalized inverses in rings

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    In this paper, it is given equivalent conditions for the absorption laws in terms of the Moore-Penrose, group, core inverse, core inverse dual, {1}, {1,2}, {1,3}, and {1,4} inverses in rings. The results given here extend the results of [X. Liu, H. Jin, a nd D.S. Cvetkovic-Ilic. The absorption laws for the generalized inverses. Appl. Math. Comp., 219:2053 2059, 2012.Hongwei, J.; Benítez López, J. (2015). The absorption laws for the generalized inverses in rings. Electronic Journal of Linear Algebra. 30(2):827-842. doi:10.13001/1081-3810.3092S82784230

    Strategies towards sustainability environmental from the local areas and the university

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    El propósito del presente trabajo es explorar un posible arreglo socioambiental pensado desde lo local que propicie el desarrollo sustentable, por medio del privilegio de la articulación de lo social (ciudadanía y educación) con el medio ambiente (capacidad de renovación). El planteamiento central es que ante un modelo social dominante que es insustentable, en el sentido que refuerza la desigualdad socioeconómica y el deterioro ambiental; se demanda pensar y actuar en formas novedosas e integradoras de lo social con la natural y del presente con el futuro para hacer posible sentar bases para un desarrollo sustentable de largo plazo. Para tal fin, se formula un arreglo que articule lo social (ciudadanía y educación) con el medio ambiente (capacidad de renovación) desde ámbitos locales, por medio de estrategias de acción gestionadas socialmente.The aim of this paper is to explore and present a suitable socio-environmental proposal conducive to sustainable development considering the local aspects emphasizing on the joint between the social (citizenship and education) with the environmental (renewability). The rationale of the study is that having a dominant unsustainable social model that reinforces socioeconomic inequality and environmental degradation, a need of developing more integrative and innovative ways to cope with the social and the natural as well as the present and the future is required in order to lay the foundations for a more long-term sustainable development. To that end, a suitable arrangement is presented in order to articulate the social aspects (citizenship and education) to the environmental ones (renewability) from a local perspective, managed through social action strategies.Fil: González López, Sergio. Universidad Autónoma del Estado de México. Instituto de Estudios sobre la Universidad.Fil: Salvador Benítez, J. Loreto. Universidad Autónoma del Estado de México. Instituto de Estudios sobre la Universidad.Fil: Arand a Sánchez, José María. Universidad Autónoma del Estado de México. Instituto de Estudios sobre la Universidad

    Educación en tiempos de resguardo involuntário

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    El trabajo tiene como objetivo reflexionar sobre las implicaciones que el resguardo físico propiciado por el Covid-19 ha tenido sobre la educación, en particular, sobre los fines del proceso educativo y el fortalecimiento de valores que permiten el enfrentamiento de condiciones inciertas y adversas. El planteamiento central es que dos de los principales riesgos que podrían enfrentarse con el resguardo voluntario/involuntario son el reforzamiento de las desigualdades sociales y de una visión instrumentalista de la educación que atentaría sobre los aspectos centrales de la formación educativa como la formación humanística que contribuye al mejoramiento social y a la educación como un medio para el ascenso social. Para tal fin, se presentan algunos de los principales rasgos de las medidas de resguardo asumidas, cuestionándose sobre su carácter voluntario o involuntario, si se trata de procedimientos nuevos que estarían modificando a los procesos sociales o si el resguardo develó una tendencia que se venía construyendo con anterioridad de aislamiento y empoderamiento de las tecnologías y a quienes beneficia. En el caso de la educación, se presenta un recorrido sobre el fortalecimiento del uso de las tecnologías digitales y se cuestiona si el resguardo físico era o no necesario; finalmente, se presenta un breve panorama sobre la situación educativa en América Latina y el Caribe

    Papel de las bacterias del ácido láctico en verduras fermentadas

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    The consumption of fermented vegetables is widespread throughout the world and represents an important component of the human diet with considerable contribution to the food supply for a world popula­tion in continuous growth. Many of the fermented vegetables share a general process which requires salting and acidification steps. Among the microorganisms responsible for fermentation, lactic acid bacteria are the most relevant with important organoleptic, quality and safety benefits. This review deals with the microbial ecology of fermented vegetables focusing on the biodiversity of lactic acid bacteria, the most important molecular tech­niques used for their identification and genotyping, their importance for the formation of biofilms as well as their use as starter cultures for obtaining high-quality and safe vegetable products.El consumo de vegetales fermenta­dos está muy extendido en el mundo y representa un componente importante de la dieta humana con un apoyo considerable a la cadena alimentaria para una población mundial en continuo crecimiento. Muchos de los vege­tales fermentados comparten un proceso general, que requiere una puesta en salmuera y acidificación. Entre los microorganismos responsables de la fermentación, las bacterias del ácido láctico son las más relevantes con una importante influencia sobre aspectos organolépticos, de calidad y seguridad del producto final. Esta revisión trata sobre la ecología microbiana de los vegetales fermentados, prestando especial atención a la biodiversidad de las bacterias del ácido láctico, las técnicas moleculares más importantes utilizadas para su identificación y genotipado, su importancia para la formación de biofilms y su uso como cultivos iniciadores multifuncionales para la obtención de productos vegetales de alta calidad y seguridad

    The impact of hunting on tropical mammal and bird populations

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    Hunting is a major driver of biodiversity loss, but a systematic large-scale estimate of hunting-induced defaunation is lacking. We synthesized 176 studies to quantify hunting-induced declines of mammal and bird populations across the tropics. Bird and mammal abundances declined by 58% (25 to 76%) and by 83% (72 to 90%) in hunted compared with unhunted areas. Bird and mammal populations were depleted within 7 and 40 kilometers from hunters’ access points (roads and settlements). Additionally, hunting pressure was higher in areas with better accessibility to major towns where wild meat could be traded. Mammal population densities were lower outside protected areas, particularly because of commercial hunting. Strategies to sustainably manage wild meat hunting in both protected and unprotected tropical ecosystems are urgently needed to avoid further defaunation

    Protective Embolization of the Gastroduodenal Artery with a One-HydroCoil Technique in Radioembolization Procedures

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    Purpose: Protective occlusion of the gastroduodenal artery (GDA) is required to avoid severe adverse effects and complications in radioembolization procedures. Because of the expandable features of HydroCoils, our goal was to occlude the GDA with only one HydroCoil to provide particle reflux protection. Methods: Twenty-three subjects with unresectable liver tumors, who were scheduled for protective occlusion of the GDA before radioembolization therapy, were included. The primary end point was to achieve a proximal occlusion of the GDA with only one detachable HydroCoil. Evaluated parameters were duration of deployment, and early (during the intervention) and late (7-21days) occlusion rates of GDA. Secondary end points included complete duration of the intervention, amount of contrast medium used, fluoroscopy rates, and adverse effects. Results: In all cases, the GDA was successfully occluded with only one HydroCoil. The selected diameter/length range was 4/10mm in 2 patients, 4/15mm in 6 patients, and 4/20mm in 15 patients. HydroCoils were implanted, on average, 3.75mm from the origin of the GDA (range 1.5-6.8mm), with an average deployment time of 2:47 (median 2:42, range 2:30-3:07) min. In 21 (91%) of 23 patients, a complete occlusion of the GDA was achieved during the first 30min after the coil implantation; however, in all patients, a late occlusion of the GDA was present after 6 to 29days. No clinical or technical complications were reported. Conclusion: We demonstrated that occlusion of the GDA with a single HydroCoil is a safe procedure and successfully prevents extrahepatic embolization before radioembolizatio

    RT-PCR-DGGE analysis to elucidate the dominant bacterial species of industrial Spanish-style green table olive fermentations

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    This paper describes the dominant bacterial species metabolically active through the industrial production of Spanish-style Manzanilla and Gordal olives. For this purpose, samples (brines and fruits) obtained at 0, 15, and 90 fermentation days were analyzed by a culture-independent approach to determine viable cells by reverse transcription of RNA and further PCR-DGGE analysis, detecting at least 7 different species. Vibrio vulnificus, Lactobacillus plantarum group, and Lactobacillus parafarraginis were present in samples from both cultivars; Lactobacillus sanfranciscensis and Halolactobacillus halophilus were detected only in Gordal samples, while Staphylococcus sp. was exclusively found at the onset of Manzanilla fermentations. Physicochemical data showed a typical fermentation profile while scanning electron microscopy confirmed the in situ biofilm formation on the olive epidermis. Different Bacillus, Staphylococcus, and Enterococcus species, not detected during the fermentation process, were also found in the solid marine salt used by the industry for preparation of brines. Elucidation of these non-lactic acid bacteria species role during fermentation is then an appealingly challenge, particularly regarding safety issues.The research has received funding from the Spanish Government (Project OliFilm AGL-2013-48300-R: www.olifilm.science.com.es). AB-C and FA-L wish to express thanks to the Spanish Government for their pre-doctoral fellowship and postdoctoral research contract (Ramón y Cajal), respectively.Peer Reviewe
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