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1.
Sensors (Basel) ; 15(3): 4781-95, 2015 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-25730482

RESUMO

Every day, millions of tons of temperature-sensitive goods are produced, transported, stored or distributed worldwide, thus making their temperature and humidity control essential. Quality control and monitoring of goods during the cold chain is an increasing concern for producers, suppliers, logistic decision makers and consumers. In this paper we present the results of a combination of RFID and WSN devices in a set of studies performed in three commercial wholesale chambers of 1848 m3 with different set points and products. Up to 90 semi-passive RFID temperature loggers were installed simultaneously together with seven motes, during one week in each chamber. 3D temperature mapping charts were obtained and also the psychrometric data model from ASABE was implemented for the calculation of enthalpy changes and the absolute water content of air. Thus thank to the feedback of data, between RFID and WSN it is possible to estimate energy consumption in the cold room, water loss from the products and detect any condensation over the stored commodities.

2.
Rev. investig. vet. Perú (Online) ; 21(2): 145-153, jul.-dic. 2010. ilus
Artigo em Espanhol | LIPECS | ID: biblio-1110731

RESUMO

El estudio tuvo por objetivo evaluar el efecto de tres dilutores (Tris, Tes y leche descremada) en la criopreservación de espermatozoides obtenidos del epidídimo de alpaca. Previamente se determinó el efecto del tiempo entre el beneficio/castración y la recuperación de los espermatozoides del epidídimo. Se utilizaron 24 testículos de alpacas para la obtención de los espermatozoides directamente del epidídimo en una solución fisiológica buferada (PBS). La recuperación de espermatozoides se realizó a las 0, 35, 48 y 72 horas (6 testículos por grupo) y se evaluó la motilidad, concentración espermática e integridad funcional de membrana. Los espermatozoides recuperados a partir de 35 horas post beneficio/castración no fueron aptos para ser congelados. Las muestras recuperadas a las 0 horas fueron diluidas con Tris, Tes y leche descremada, enfriadas desde 35 a 5°C en 90 minutos, envasadas en pajillas de 0.25 ml y congeladas en nitrógeno líquido. Se evaluó la motilidad, integridad funcional de membrana y vitalidad/integridad acrosomal en las muestras descongeladas. La motilidad fue de 14.0, 8.6 y 17.0% en los grupos Tris, Tes y leche descremada, respectivamente, donde el grupo leche descremada fue significativamente mejor que el grupo Tes (p<0.05). Los porcentajes de integridad funcional de membrana y vitalidad/integridad acrosomal fueron similares entre los tres grupos. Se concluye que los tres dilutores brindan efectos similares para la criopreservación de espermatozoides epididimarios de alpaca.


The objective of this study was to evaluate the effect of three semen extenders (skim milk, Tris, and Tes) on cryopreservation of epididymal alpaca sperm. Previously, the effect of timespan since slaughtering or castration to the recovery of epididymal sperm was evaluated. Twenty-four alpaca testicles were used to obtain sperm from the epididymis in a buffered saline solution (PBS). The recovery of spermatozoa was performed at 0, 35, 48, and 72 hours (6 testes per group) after slaughtering or castration. Sperm motility, concentration, and sperm membrane functional integrity were analyzed. Sperm recovered after 35 hours was not usable for cryopreservation. Sperm samples recovered at 0 hours were subjected to the process of freezing. Samples were diluted with skim milk, Tris, and Tes, cooled from 35 to 5 °C in 90 minutes, packed into 0.25 ml straws and frozen in liquid nitrogen. After thawing, straws were evaluated by motility, sperm membrane functional integrity and vitality/acrosome integrity. Motility was 17.0, 14.0, and 8.6% on skim milk, Tris and Tes groups respectively, where the skim milk group was significantly better than the Tes (p<0.05). Percentages of sperm membrane functional integrity and vitality/acrosomal integrity were similar among the three extenders. It was concluded that all three extenders provided similar effects for the cryopreservation of epididymal alpaca spermatozoa.


Assuntos
Animais , Camelídeos Americanos , Criopreservação , Diluição , Epididimo , Espermatozoides , Preservação do Sêmen
3.
Rev. investig. vet. Perú (Online) ; 21(1): 26-34, ene.-jun. 2010. ilus
Artigo em Espanhol | LIPECS | ID: biblio-1110711

RESUMO

Se evaluó el efecto la glucosa, fructosa, trehalosa y sacarosa, como componentes del diluyente, sobre la viabilidad espermática en semen canino refrigerado a 5 °C. La fracción espermática de 16 eyaculados de perro fue distribuida en cinco alícuotas conteniendo un diluyente a base de Tris - ácido cítrico - yema de huevo, pero con un azúcar distinto, además del control sin azúcar. Los cinco tratamientos se evaluaron a las 24, 48, 72 y 96 horas de refrigeración en base a motilidad progresiva e integridad funcional de membrana mediante la prueba hipoosmótica (HOS). En todos los grupos, a excepción del grupo control, la motilidad espermática se mantuvo dentro de rangos aceptables durante el estudio (90% en el día 0 hasta cerca de 60% en el día 4). Sin embargo, la integridad de membrana se mantuvo ligeramente superior en los grupos con azúcar (87-90%) en comparación con el grupo control (83-85%). La glucosa y sacarosa mostraron mejores resultados de motilidad y HOS. Se concluye que no se genera un daño significativo sobre la membrana espermática durante la refrigeración a 5 °C del semen canino, y que la utilización de cualquiera de los azúcares como sustrato energético para los espermatozoides, en especial glucosa y sacarosa, es de gran importancia para el mantenimiento de niveles apropiados de motilidad espermática e integridad funcional de membrana.


The effect of glucose, fructose, trehalose, and sucrose, as components of the extender, was evaluated on canine sperm viability during refrigeration at 5 ºC. The spermatic fraction of 16 dog ejaculations were distributed in 5 aliquots containing an extender based on Tris – citric acid – egg yolk, but differing in the presence of one of the sugars, plus a control without sugar. The five treatments were evaluated after 24, 48, 72, and 96 hours of refrigeration in relation to progressive motility and functional integrity of the membrane by the hypoosmotic swelling test (HOS). All groups, with the exception of the control group, the sperm motility maintained within acceptable ranges during the study (90% on day 0 and 60% on day 4). The integrity of the membrane remained slightly superior in groups with sugar (87-90%) in comparison with the control group (83-85%). The glucose and sucrose showed the best results in motility and HOS. It is concluded that no significant damage occurred on the sperm membrane while keeping semen at 5 ºC, and that the use of any of the tested sugars as energy-giving substrate for the sperm cells (especially glucose and sucrose) is of great importance for the maintenance of appropriate levels of sperm motility and functional integrity of the membrane.


Assuntos
Animais , Cães , Frutose , Glucose , Preservação do Sêmen , Sacarose , Trealose , Dissacarídeos , Monossacarídeos
4.
Sensors (Basel) ; 10(5): 4968-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-22399917

RESUMO

Quality control and monitoring of perishable goods during transportation and delivery services is an increasing concern for producers, suppliers, transport decision makers and consumers. The major challenge is to ensure a continuous 'cold chain' from producer to consumer in order to guaranty prime condition of goods. In this framework, the suitability of ZigBee protocol for monitoring refrigerated transportation has been proposed by several authors. However, up to date there was not any experimental work performed under real conditions. Thus, the main objective of our experiment was to test wireless sensor motes based in the ZigBee/IEEE 802.15.4 protocol during a real shipment. The experiment was conducted in a refrigerated truck traveling through two countries (Spain and France) which means a journey of 1,051 kilometers. The paper illustrates the great potential of this type of motes, providing information about several parameters such as temperature, relative humidity, door openings and truck stops. Psychrometric charts have also been developed for improving the knowledge about water loss and condensation on the product during shipments.


Assuntos
Refrigeração , Transportes , Verduras/fisiologia , Tecnologia sem Fio , Aceleração , Ar , Análise de Variância , Umidade , Luz , Pressão , Reprodutibilidade dos Testes , Tecnologia sem Fio/instrumentação
5.
Sensors (Basel) ; 9(6): 4728-50, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22408551

RESUMO

The aim of the present paper is to review the technical and scientific state of the art of wireless sensor technologies and standards for wireless communications in the Agri-Food sector. These technologies are very promising in several fields such as environmental monitoring, precision agriculture, cold chain control or traceability. The paper focuses on WSN (Wireless Sensor Networks) and RFID (Radio Frequency Identification), presenting the different systems available, recent developments and examples of applications, including ZigBee based WSN and passive, semi-passive and active RFID. Future trends of wireless communications in agriculture and food industry are also discussed.

6.
Rev. investig. vet. Perú (Online) ; 18(2): 107-114, ene-jun. 2007. ilus
Artigo em Espanhol | LIPECS | ID: biblio-1110646

RESUMO

El objetivo del estudio fue evaluar el efecto de tres dilutores y cuatro combinaciones de dos agentes crioprotectores permeantes más dos no permeantes sobre la calidad del semen ovino post-descongelamiento. Para esto, en una primera fase se evaluaron entre tres dilutores (A, B y C) y el más adecuado se usó en una segunda fase, donde se evaluaron las siguientes combinaciones de agentes crioprotectores permeantes y no permeantes: 1) Glicerol - Trehalosa, 2) Glicerol - Sacarosa, 3) Etilenglicol - Trehalosa y 4) Etilenglicol - Sacarosa. En el experimento 1, se encontró que el Dilutor A mantenía mejor la motilidad progresiva, viabilidad e integridad acrosomal post-descongelamiento en comparación con los dilutores B y C, por lo que el Dilutor A se empleó en el experimento 2. En este ensayo se encontró que la motilidad progresiva, la viabilidad e integridad acrosomal, la termoresistencia y la integridad de membrana plasmática post-descongelamiento fue mejor en los grupos con glicerol-sacarosa y glicerol-trehalosa en comparación con los grupos con etilenglicol-sacarosa y etilenglicol-trehalosa. Esto demuestra que el glicerol es un mejor crioprotector permeante en comparacion con el etilenglicol; sin embargo, no hubo diferencia en el uso de sacarosa o trehalosa. Se concluye que un dilutor con las características del dilutor A, utilizando glicerol más trehalosa o sacarosa, constituye una buena alternativa para la criopreservación de semen ovino.


The objective of the study was to evaluate the effect of three extenders and four combinations of two permeant and two non permeant cryoprotectant agents on the quality of post thaw ram semen. In Experiment 1, three extender were evaluated (A, B, and C) in order to select the best for the next step. In Experiment 2, different combinations of cryoprotectant agents were evaluated as follow: 1) Glycerol–Trehalose, 2) Glycerol–Sucrose, 3) Ethylene glycol-Trehalose, and 4) Ethylene glycol–Sucrose. In experiment 1, motility, viability and acrosomal integrity in extender A were higher than in extender B and extender C, and therefore, extender A was used for experiment 2. In this assay, motility, viability and acrosomal integrity, thermoresistance, and plasmatic membrane integrity were higher in groups Glycerol-sucrose and Glycerol-trehalose in comparison with groups Ethilene glycol-sucrose and Ethilene glycol-trehalose. However, there were not significative differences between sucrose or trehalose. In conclusion, an extender with characteristics of extender A using glycerol plus trehalose or sucrose constitute a good alternative for cryopreservation of ram semen.


Assuntos
Animais , Criopreservação , Crioprotetores/classificação , Ovinos , Sêmen
7.
Rev. investig. vet. Perú (Online) ; 18(2): 99-106, ene-jun. 2007. ilus
Artigo em Espanhol | LIPECS | ID: biblio-1110647

RESUMO

Se emplearon 32 muestras de semen procedentes de cuatro ovinos a fin de ser criopreservadas con la adición dos antioxidantes: Tempo (2,2,6,6 tetrametil-1-piperidiniloxil) y Tempol (4-hidroxi 2,2,6,6 tetrametil-1-piperidiniloxil), en concentraciones de 0.5, 1.0 y 2.5 mM, para evaluar el efecto postdescongelamiento que pudieran tener sobre la motilidad progresiva, la viabilidad e integridad acrosomal y la capacitación espermática prematura. En cada concentración de los dos antioxidantes y del grupo control se utilizó un dilutor en base a Tris, realizándose ocho repeticiones, cada una con cuatro muestras de semen. Los resultados obtenidos demuestran que la adición de Tempo a una concentración de 0.5 mM mejora significativamente la calidad del semen criopreservado en comparación con el grupo control (p<0.05), incrementado los porcentajes de motilidad progresiva (79 vs. 67 por ciento), viabilidad e integridad acrosomal (70 vs. 58 por ciento) y reduciendo la capacitación espermática prematura (9 vs.15 por ciento). Por otro lado, la adición de Tempol disminuyó la calidad seminal postdescongelamiento en comparación con el control. En conclusión, la adición de Tempo 0.5 mM en un dilutor en base a Tris, al finalizar la fase de enfriamiento, podría constituir una estrategia para mejorar la calidad de semen ovino criopreservado.


Thirty-two semen samples from four rams were frozed using two antioxidants, Tempo (2,2,6,6 tetramethyl-1-piperidinyloxyl) and Tempol (4-hidroxi 2,2,6,6 tetramethyl-1-piperidinyloxyl), each one in concentrations of 0.5, 1.0, and 2.5 mM, to evaluate the effects on post-thawing motility, viability, acrosomal integrity, and earlier sperm capacitation. Eight replications for each antioxidant concentration and control group, were done using four semen samples per replication. Semen samples were diluted on a Tris extender. Results showed that Tempo 0.5 mM improved frozen semen quality in comparison with control group (p<0.05), by increasing progresive motility (79 vs. 67 por ciento), viability and acrosomal integrity (70 vs. 58 por ciento), and decreasing earlier sperm capacitation (9 vs. 15 por ciento). On the other hand, Tempol decreased frozen semen quality. In conclusion, the use of Tempo 0.5 mM on a Tris extender, at the end of the cooling process, could be an alternative for improving the quality of frozed ram semen.


Assuntos
Animais , Antioxidantes , Criopreservação , Ovinos , Sêmen
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