1,627 research outputs found
Brans-Dicke wormholes in nonvacuum spacetime
Analytical wormhole solutions in Brans-Dicke theory in the presence of matter
are presented. It is shown that the wormhole throat must not be necessarily
threaded with exotic matter.Comment: Minor corrections, to be published in Phys. Rev.
Diseño de un silo de fondo cónico para almacenar maíz con capacidad de 25 toneladas con carga y descarga
The silo is the most important form of storage the grain used in the agricultural industry, thanks to its efficiency for preserving the quality and nutrients of the grain of maize, nowadays maize is an essential part in the economy of our country the same form the maize also important for human consumption because of their excellent properties to stimulate the mind, strengthen the brain and help our organism.
This project is oriented to the structural design of a cylindrical silo made of sheet metal with a capacity of twenty-five tons,has the advantage of being removable for easy transport of it, also it will store maize efficiently and safely. with this proyect developing not only we will get adecuate grain storage, but the transport and assembly of the container is also provided.
In this degree work we know the ways to preserve the grain of corn in addition to its features in order to facilitate the storage of grain in the silo. The silo is designed based on the Eurocódigo1: Actions in silos and tanks structures (EN 1991-4), which gives rules for structural calculation, it is performed by the influence of various parameters such as the density of grain, pressures acting on the silo walls, specific gravity among others.Los silos son las formas de almacenamiento de grano más importantes utilizadas en la industria agrícola por su eficiencia al preservar la calidad y los nutrientes del grano de maíz, en la actualidad el maíz es parte fundamental en la economía de nuestro país como también es importante para el consumo humano debido a sus excelentes propiedades para estimular el ánimo y fortalecer al cerebro gracias a que contiene un gran número de proteínas asimilables por el organismo.
Este proyecto está orientado al diseño estructural de un silo cilíndrico elaborado de chapa metálica de 25 toneladas tiene la ventaja de ser desmontable para su fácil transportación, Además almacenara maíz de forma eficiente y segura. Al desarrollar este proyecto no solo se obtendrá un adecuado almacenamiento del grano, sino también, se facilitará el transporte y armado del recipiente.
En el trabajo de grado se conoce las formas para preservar al grano de maíz además de sus características con el fin de facilitar el almacenaje del grano en el silo. El silo se encuentra diseñado en base al Eurocódigo1: Acciones en estructuras silos y depósitos (UNE-EN 1991-4), la cual da unas reglas para el cálculo estructural que se realiza bajo la influencia de distintos parámetros como la densidad del grano, capacidad de almacenamiento, presiones que actúan sobre las paredes del silo, peso específico entre otras
Sharp emergence of feature-selective sustained activity along the dorsal visual pathway.
Sustained activity encoding visual working memory representations has been observed in several cortical areas of primates. Where along the visual pathways this activity emerges remains unknown. Here we show in macaques that sustained spiking activity encoding memorized visual motion directions is absent in direction-selective neurons in early visual area middle temporal (MT). However, it is robustly present immediately downstream, in multimodal association area medial superior temporal (MST), as well as and in the lateral prefrontal cortex (LPFC). This sharp emergence of sustained activity along the dorsal visual pathway suggests a functional boundary between early visual areas, which encode sensory inputs, and downstream association areas, which additionally encode mnemonic representations. Moreover, local field potential oscillations in MT encoded the memorized directions and, in the low frequencies, were phase-coherent with LPFC spikes. This suggests that LPFC sustained activity modulates synaptic activity in MT, a putative top-down mechanism by which memory signals influence stimulus processing in early visual cortex
Pandemic and conservation of freshwater molluscs in Argentina
To date, the impact of the Coronavirus COVID-19 pandemic in Argentina has been quite significant in terms of social activity, but more specifically in terms of scientific field research (because of the absence of collection permits, the restrictions on circulation, the closure of laboratories, border controls and social distancing, among other issues). Completion of research by the present authors on issues related to the conservation and distribution of gastropods and freshwater bivalves from Argentina, for example by Torres & Darrigran (2019) and de Lucía & Gutiérrez Gregoric (2020), has been delayed because of laboratories being closed or field work not being possible. Even though the quality of the thesis work of these doctoral students (de Lucía, Torres), and of other students and researchers, has not diminished, its completion has been held back.Fil: Gutierrez Gregoric, Diego Eduardo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: de Lucia, Micaela. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Invertebrados; ArgentinaFil: Torres, Santiago Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Santa Cruz. Universidad Tecnológica Nacional. Facultad Regional Santa Cruz. Centro de Investigaciones y Transferencia de Santa Cruz. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia de Santa Cruz; ArgentinaFil: Darrigran, Gustavo Alberto. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin
Distribution of the Unionida (Bivalvia, Paleoheterodonta) from Argentina and its conservation in the Southern Neotropical Region
Bivalves are one of the most representative groups in the Phylum Mollusca, with over 1,100 freshwater species around the world except Antarctica. About 900 of these species belong to the Order Unionida Gray, 1854. In South America, the distributional range of the Unionida includes all countries in the region and extends as far south as the lakes and rivers of Argentinean- Chilean Patagonia. With the aim of generating distribution maps for the different genera of Unionida in Argentina, we consulted the databases of the nation’s main official malacological collections. The data were analyzed and georeferenced using the point-radius method.
Spatial analyses were performed with the software Q-GIS 2.16.3 Nødebo using vector layers under the 2007 Argentinean Geodesic Positions reference system. A total 1,833 lots were analyzed, of which it was possible to georeference 1,503. The distribution of Unionida in Argentinean territory was analyzed according to political provinces, Surface Drainage Basins and the Argentinean Protected Areas. Species richness was analyzed using the surface drainage basins of Argentina. We generate distribution maps for each genus and discuss the species threat status and conservation degree in the region. Only six (18%) of the Unionida present in Argentina have been classified by the IUCN, four are Least Concern and two are Data Deficient. This pattern is also valid for all of South America. More than 95% of the distributional range of the Unionida has no protected area. Conservation management is necessary for the preservation of Unionida diversity in southern South America.Facultad de Ciencias Naturales y Museo (FCNM
Cost-effective printed electrodes based on emerging materials applied to biosignal acquisition
In this paper flexible printed electrodes applicable to wearable electronics are presented. Using innovative
materials as Laser Induced Graphene (LIG) and printed electronics, three type of electrodes based in
LIG, silver chloride and carbon inks have been compared during the acquisition of bipotentials as
electrocardiogram, electromyogram and electrooculogram. For this last one, a completely new framework
for acquisition have been developed. This framework is based in a printed patch which integers 6 electrodes
for the EOG acquisitions and an ad-hoc signal processing to detect the direction and amplitude of the
eye movement. The performance of the developed electrodes have been compared with commercial ones
using the characteristics parameters of each signal as comparative variables. The results obtained for the
flexible electrodes have shown a similar performance than the commercial electrodes with an improvement
in the comfort of the user.Spanish Ministry of Education, Culture and Sport (MECD)/FEDER-EU
TEC2017-89955-P
FPU16/01451
FPU18/01376BBVA FoundationUniversity of Granad
Low-Cost Energy-Autonomous Sensor Nodes Through RF Energy Harvesting and Printed Technology
The irruption of Internet of Things and 5G in our society comes along with several technological challenges to overcome. From an overall perspective, the low-cost and environmental friendliness of these technologies need to be ensured for their universal deployment in different areas, starting with the sensors and finishing with the power sources. To address these challenges, the production and maintenance of a great number of sensor nodes incur costs, which include manufacturing and integration in mass of elements and sub-blocks, changing or recharging of batteries, as well as management of natural resources and waste. In this article, we demonstrate how Radio Frequency Energy Harvesting (RFEH) and printed flexible technology (a growing technology for sensors) can solve these concerns through costeffective mass-production and utilization of energy harvesting for the development of energy-autonomous nodes, as part of a wireless sensor network. We present as illustration a sprayed flexible relative humidity sensor powered with RFEH under the store-and-use principle.This work was partially supported by the ECSEL Joint Undertaking through the Electronic Component Systems for European Leadership Joint Undertaking under grant agreement No 737434. This Joint Undertaking receives support from the German Federal Ministry of Education and Research and the European Union’s Horizon 2020 research and innovation program and Slovakia, Netherlands, Spain, Italy. In addition, the Spanish Ministry of Education, Culture and Sport (MECD) and the European Union supported it through the pre-doctoral grant FPU16/01451 and the fellowship H2020-MSCA-IF-2017794885-SELFSENS
Using Citizen Science Gamification in Agriculture Collaborative Knowledge Production
RUC-APS is an international project run by 16 research institutions. The project's main goal is empowering agriculture production systems through innovative knowledge-based ICT solutions to deal with high risk and uncertain conditions. In this context, a Semantic Mediawiki is desired to support the various stakeholders in the agriculture value chain in the task of capturing and sharing agricultural best practices. Applying gamification to Wikis is one strategy to encourage the community to participate, and It could be achieved by attaching Metagame, a gamification layer system. However, It could be risky because the tunning of a gamification system in the production face of the wiki could be perceived by the users as a bug in the system. To avoid this situation, a simulation based on the real historical data of the Agriculture community in Wikipedia from 2001 to 2018 was performed. The simulation revealed that is not obvious to generate a system of awards on the type of actions carried out by the Wikipedia editors. The construction of knowledge is done in very small portions, and some of them can be confused with improvements or corrections instead of contributions. Indeed, It shows the importance of tuning the reward parameters, because that allows advancing in the Metagame rank evolution.Laboratorio de Investigación y Formación en Informática Avanzad
Using Citizen Science Gamification in Agriculture Collaborative Knowledge Production
RUC-APS is an international project run by 16 research institutions. The project's main goal is empowering agriculture production systems through innovative knowledge-based ICT solutions to deal with high risk and uncertain conditions. In this context, a Semantic Mediawiki is desired to support the various stakeholders in the agriculture value chain in the task of capturing and sharing agricultural best practices. Applying gamification to Wikis is one strategy to encourage the community to participate, and It could be achieved by attaching Metagame, a gamification layer system. However, It could be risky because the tunning of a gamification system in the production face of the wiki could be perceived by the users as a bug in the system. To avoid this situation, a simulation based on the real historical data of the Agriculture community in Wikipedia from 2001 to 2018 was performed. The simulation revealed that is not obvious to generate a system of awards on the type of actions carried out by the Wikipedia editors. The construction of knowledge is done in very small portions, and some of them can be confused with improvements or corrections instead of contributions. Indeed, It shows the importance of tuning the reward parameters, because that allows advancing in the Metagame rank evolution
Brans-Dicke wormholes in nonvacuum spacetime
Analytical wormhole solutions in Brans-Dicke theory in the presence of matter are presented. It is shown that the wormhole throat must not be necessarily threaded with exotic matter.Facultad de Ciencias Exacta
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