928 research outputs found

    Development of model based sensors for the supervision of a solar dryer

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    Solar dryers are increasingly used in developing countries as an alternative to drying in open air, however the inherent variability of the drying conditions during day and along year drive the need for achieving low cost sensors that would enable to characterize the drying process and to react accordingly. This paper provides three different and complementary approaches for model based sensors that make use of the psychrometric properties of the air inside the drying chamber and the temperature oscillations of the wood along day. The simplest smart sensor, Smart-1, using only two Sensirion sensors, allows to estimate the accumulated water extracted from wood along a complete drying cycle with a correlation coefficient of 0.97. Smart-2 is a model based sensor that relays on the diffusion kinetics by means of assesing temperature and relative humidity of the air inside the kiln. Smart-2 model allows to determine the diffusivity, being the average value of D for the drying cycle studied equal to 5.14 × 10−10 m2 s−1 and equal to 5.12 × 10−10 m2 s−1 for two experiments respectively. The multidistributed supervision of the dryer shows up the lack of uniformity in drying conditions supported by the wood planks located in the inner or center of the drying chamber where constant drying rate kinetics predominate. Finally, Smart-3 indicates a decreasing efficiency along the drying process from 0.9 to 0.

    Plataforma de control de bajo coste para incubadoras de perdices basada en sensores ambientales y de gases.

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    Las incubadoras de huevos requieren un buen control de la temperatura (37.5-37.8 ºC) y de la humedad relativa (45-60%) durante todo el proceso de incubación. Aunque la concentración de dióxido de carbono es determinante para establecer una buena tasa de ventilación, así como para determinar el estado de proceso de desarrollo de los embriones (De Smit et al., 2006; Han et al., 2011), las incubadoras industriales normalmente no incorporan sensor de CO2. En trabajos previos de los autores se realizó la modelización del gradiente de temperatura y humedad relativa en el interior de una incubadora semi-industrial usando una red tridimensional de sensores, observándose que las variaciones espaciales eran despreciables; haciendo posible usar un único sensor en un punto de control. En dichos ensayos previos se emplearon módulos comerciales de adquisición de datos y de control, cuyo principal inconveniente es el coste considerando el perfil del usuario final: empresario cinegético a tiempo parcial en esta actividad. En la actualidad existen diversas plataformas de hardware y software libre con un bajo coste que se pueden emplear para controlar y monitorizar procesos a través de sus entradas y salidas digitales y analógicas. Una de estas plataformas es Arduino, creada en 2005 como una herramienta para estudiantes. En este trabajo se presenta el diseño y validación de un sistema de control de una incubadora industrial de perdices, empleando un sensor de temperatura y humedad relativa y un sensor de CO2 basado en la tecnología de infrarrojo no dispersivo (NDIR),conectados a una placa ArduinoTM MEGA. La producción de CO2 se ha empleado para modelizar el desarrollo embrionario de los huevos, y estimar el punto final de la incubación. Se dispone de datos relativos a la tasa de nacimientos, en todos los casos cercana al 70%; muy elevado considerando que se desconoce la tasa inicial de huevos fecundados

    Design of a solar incubator. Part 1: Monitoring temperature and enthalpy gradients under commercial production

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    The real increase in energy prices and the intention of reducing pollutant emissions in developed countries makes interesting to use solar energy in all the processes where its application is possible. As it is demonstrated in countries sited at latitudes with optimal conditions of solar radiation and temperature, it is possible to use solar energy as heat source for small-scale hatchery [1,2], but beyond, making a design for proper installation; it is possible to use solar energy as main or support energy source in medium and large size incubators . Monitoring of a normal actual process using temperature and relative humidity sensors is necessary to know the actual operating conditions that the solar heating system must be designed and sized for. Moreover, the identification and analysis of temperature and enthalpy gradients inside the incubator is of major importance

    Smart Sensing Applications in the Agriculture and Food Industry

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    This chapter is structured in three main sections: an introduction to the smart concept and smart quality control, a review of the state of the art in integrated sensors, embedded systems, and the third one which is dedicated to a review of three case studies. The case studies refer to three results lines that are under taken by the LPF-TAGRALIA in the field of smart sensing. It provides examples of how to develop smart capabilities within standard low cost sensors. A variety of smart capabilities have been selected such as dynamic analysis of physical magnitudes, transmission diagnosis and such reliability and a full range of examples of analytical models of wood drying that can be incorporated to sensor chips to enhance sensor performs and to enable the term smart sensor. Each of the three sections of the chapter is independent and so the reader can decide where to start from according to their particular expertise. For unfamiliar readers with smart technologies, all of them might be of interest, while for experienced readers in the subject the case studies directly are probably the most relevant issue

    Registro y análisis del historial térmico durante el almacenamiento y el transporte refrigerado de productos mínimamente procesados

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    En este estudio se presenta el análisis de las temperaturas registradas durante el almacenamiento y el transporte refrigerado de un pequeño lote de hortalizas de hoja mínimamente procesadas, monitorizadas mediante tarjetas Turbotag® y sensores inalámbricos Nlaza ubicados en el interior de las bolsas y en diferentes lugares de las cajas de cartón que contienen esas bolsas. El objetivo de este trabajo es generar protocolos de distribución y configuración de sensores y de procesado y análisis de los datos para el seguimiento y control continuo de la temperatura durante el transporte de productos refrigerados; se centra en el potencial de la utilización de la sensórica inalámbrica, evaluando la capacidad de los sensores en la obtención de datos y su comunicación, evaluando la cantidad de paquetes perdidos Abstract This study presents an analysis of the temperatures during storage and refrigerated transport of a small batch of minimally processed leafy vegetables, monitored by TurboTag® cards and wireless sensors Nlaza located inside the bags and in different places cardboard boxes containing the bags. The aim of this paper is to generate distribution protocols and configuration of sensors and processing and analysis of data for continuous monitoring and control of temperature during transport of refrigerated products. It focuses on the potential use of wireless sensor evaluating the ability of the sensor data acquisition and communication, evaluating the packet los

    Development of smart sensors for the supervision of a solar dryer: agro-products dehydration application

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    Solar dryers are increasingly used in developing countries as an alternative to drying in open air, however the inherent variability of the drying conditions during day and along year drive the need for achieving low cost sensors that would enable to characterize the drying process and to react accordingly. This paper provides an approach for smart sensors that make use of the psychrometric properties of the air inside the drying chamber along day. The proposed model shows a high agreement with bibliographic dat

    Ash pollen immunoproteomics: Identification, immunologic characterization, and sequencing of 6 new allergens

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    Immunoproteomics, IgE-inhibition assays and cDNA-cloning reveals that ash and olive allergenic protein profiles are mostly equivalent, thus explaining their high cross reactivity. Our data suggest simplifying diagnosis of patients by using indistinctly ash or olive pollen

    Control of a solar dryer through using a fuzzy logic and low-cost model-based sensor

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    Solar drying is one of the important processes used for extending the shelf life of agricultural products. Regarding consumer requirements, solar drying should be more suitable in terms of curtailing total drying time and preserving product quality. Therefore, the objective of this study was to develop a fuzzy logic-based control system, which performs a ?human-operator-like? control approach through using the previously developed low-cost model-based sensors. Fuzzy logic toolbox of MatLab and Borland C++ Builder tool were utilized to develop a required control system. An experimental solar dryer, constructed by CONA SOLAR (Austria) was used during the development of the control system. Sensirion sensors were used to characterize the drying air at different positions in the dryer, and also the smart sensor SMART-1 was applied to be able to include the rate of wood water extraction into the control system (the difference of absolute humidity of the air between the outlet and the inlet of solar dryer is considered by SMART-1 to be the extracted water). A comprehensive test over a 3 week period for different fuzzy control models has been performed, and data, obtained from these experiments, were analyzed. Findings from this study would suggest that the developed fuzzy logic-based control system is able to tackle difficulties, related to the control of solar dryer process

    Phosphatidylserine-Liposomes promote tolerogenic features on dendritic cells in human type 1 diabetes by apoptotic mimicry

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    Type 1 diabetes (T1D) is a metabolic disease caused by the autoimmune destruction of insulin-producing β-cells. With its incidence increasing worldwide, to find a safe approach to permanently cease autoimmunity and allow β-cell recovery has become vital. Relying on the inherent ability of apoptotic cells to induce immunological tolerance, we demonstrated that liposomes mimicking apoptotic β-cells arrested autoimmunity to β-cells and prevented experimental T1D through tolerogenic dendritic cell (DC) generation. These liposomes contained phosphatidylserine (PS)-the main signal of the apoptotic cell membrane-and β-cell autoantigens. To move toward a clinical application, PS-liposomes with optimum size and composition for phagocytosis were loaded with human insulin peptides and tested on DCs from patients with T1D and control age-related subjects. PS accelerated phagocytosis of liposomes with a dynamic typical of apoptotic cell clearance, preserving DCs viability. After PS-liposomes phagocytosis, the expression pattern of molecules involved in efferocytosis, antigen presentation, immunoregulation, and activation in DCs concurred with a tolerogenic functionality, both in patients and control subjects. Furthermore, DCs exposed to PS-liposomes displayed decreased ability to stimulate autologous T cell proliferation. Moreover, transcriptional changes in DCs from patients with T1D after PS-liposomes phagocytosis pointed to an immunoregulatory prolife. Bioinformatics analysis showed 233 differentially expressed genes. Genes involved in antigen presentation were downregulated, whereas genes pertaining to tolerogenic/anti-inflammatory pathways were mostly upregulated. In conclusion, PS-liposomes phagocytosis mimics efferocytosis and leads to phenotypic and functional changes in human DCs, which are accountable for tolerance induction. The herein reported results reinforce the potential of this novel immunotherapy to re-establish immunological tolerance, opening the door to new therapeutic approaches in the field of autoimmunity

    Phosphatidylserine-liposomes Promote Tolerogenic Features on Dendritic cells in human Type 1 Diabetes by apoptotic Mimicry

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    Type 1 diabetes (T1D) is a metabolic disease caused by the autoimmune destruction of insulin-producing β-cells. With its incidence increasing worldwide, to find a safe approach to permanently cease autoimmunity and allow β-cell recovery has become vital. Relying on the inherent ability of apoptotic cells to induce immunological tolerance, we demonstrated that liposomes mimicking apoptotic β-cells arrested autoimmunity to β-cells and prevented experimental T1D through tolerogenic dendritic cell (DC) generation. These liposomes contained phosphatidylserine (PS)—the main signal of the apoptotic cell membrane— and β-cell autoantigens. To move toward a clinical application, PS-liposomes with optimum size and composition for phagocytosis were loaded with human insulin peptides and tested on DCs from patients with T1D and control age-related subjects. PS accelerated phagocytosis of liposomes with a dynamic typical of apoptotic cell clearance, preserving DCs viability. After PS-liposomes phagocytosis, the expression pattern of molecules involved in efferocytosis, antigen presentation, immunoregulation, and activation in DCs concurred with a tolerogenic functionality, both in patients and control subjects. Furthermore, DCs exposed to PS-liposomes displayed decreased ability to stimulate autologous T cell proliferation. Moreover, transcriptional changes in DCs from patients with T1D after PS-liposomes phagocytosis pointed to an immunoregulatory prolife. Bioinformatics analysis showed 233 differentially expressed genes. Genes involved in antigen presentation were downregulated, whereas genes pertaining to tolerogenic/ anti-inflammatory pathways were mostly upregulated. In conclusion, PS-liposomes phagocytosis mimics efferocytosis and leads to phenotypic and functional changes in human DCs, which are accountable for tolerance induction. The herein reported results reinforce the potential of this novel immunotherapy to re-establish immunological tolerance, opening the door to new therapeutic approaches in the field of autoimmunity.This work has been funded by a grant from the Spanish Government (FIS PI15/00198) co-financed with the European Regional Development funds (FEDER), by Fundació La Marató de TV3 (28/201632-10), by Catalan AGAUR (project 2014 SGR1365) and by CERCA Program/Generalitat de Catalunya. CIBER of Diabetes and Associated Metabolic Diseases (CIBERDEM) is an initiative from Instituto de Salud Carlos III. ICN2 acknowledges the support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Program, under grant SEV-2013-0295. This work has been supported by positive discussion through A FACTT network (Cost Action BM1305: www.afactt.eu). COST is supported by the EU Framework Program Horizon 2020. SR-F is supported by the Agency for Management of University and Research Grants (AGAUR) of the Generalitat de Catalunya
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