Influencia de factores socioeconómicos en el nivel de adopción de tecnología de trigo, en el Proyecto de Desarrollo Rural del altiplano de Nariño

Las políticas de desarrollo rural que se han diseñado en los últimos años, han echo énfasis a la transferencia de tecnología. Esto hace pensar que la difusión de innovaciones técnicas y la adopción de las mismas van a producir en los agricultores las transformaciones necesarias para contribuir al cambio denominado desarrollo.Trigo-Triticum aestivuMaestría en CienciasMaestrí

The increase in phosphorylation levels of serine residues of protein HSP70 during holding at 17ºC is concomitant with a higher cryotolerance of boar spermatozoa

Boar-sperm cryopreservation is not usually performed immediately after semen collection, but rather a holding time (HT) of 4 h-30 h at 17 u C is spent before starting this procedure. Taking this into account, the aim of this study was to go further in- depth into the mechanisms underlying the improving effects of HT at 17 u C on boar-sperm cryotolerance by evaluating the effects of two different HTs (3 h and 24 h) on overall boar-sperm function and survival before and after cryopreservation. Given that phospho/dephosphorylation mechanisms are of utmost importance in the overall regulation of sperm function, the phosphorylation levels of serine residues (pSer) in 30 different sperm proteins after a 3 h- or 24 h-HT period were also assessed. We found that a HT of 24 h contributed to a higher sperm resistance to freeze-thawing procedures, whereas mini-array protein analyses showed that a HT of 24 h induced a significant (P,0.05) increase in pSer (from 100.06 1.8 arbitrary units in HT 3 h to 150.2 65.1 arbitrary units in HT 24 h) of HSP70 and, to a lesser extent, in protein kinases GSK3 and total TRK and in the cell-cycle regulatory protein CDC2/CDK1. In the case of HSP70, this increase was confirmed through immunoprecipation analyses. Principal component and multiple regression analyses indicated that a component explaining a percentage of variance higher than 50% in sperm cryotolerance was significantly correlated with pSer levels in HSP70. In addition, from all the parameters evaluated before freeze-thawing, only pSer levels in HSP70 resulted to be able to predict sperm cryotolerance. In conclusion, our results suggest that boar spermatozoa modulate its function during HT, at least partially, by changes in pSer levels of proteins like HSP70, and this is related to a higher cryotoleranc

Efecto del arreglo silvopastoril aliso (AlnusAcuminata K.) y kikuyo (PennisetumClandestinumH.) sobre el comportamiento productivo en novillas Holstein en el altiplano del departamento de Nariño

Se compararon variables agronómicas y bromatológicas de un monocultivo de kikuyo (Pennisetumclandestinum) (S1) y un sistema silvopastoril (S2), sobre comportamiento productivo de novillas Holstein, en el Centro Experimental de Transferencia de Tecnología FEDEPAPA, municipio de Pasto (Colombia). Los indicadores agronómicos evaluados fueron: producción de forraje verde, producción de materia seca y altura del pasto. Además, un análisis bromatológico fue realizado para determinar la calidad del forraje: porcentaje de materia seca, proteína cruda, extracto etéreo, fibra cruda, FDN, FDA, celulosa, hemicelulosa, lignina, minerales. Se usó un diseño experimental Swith Back (reversible) y se aplicó el estadístico t de Student para comparar los indicadores. Diferencias estadísticas fueron registradas entre S1 en la altura del pasto de 23,2 cm y S2 con 36,2 cm, respectivamente. Igualmente, diferencias estadísticas en el contenido de P del pasto, el S2 mostró mayor contenido, con un promedio de 0,39%. La ganancia de peso fue mayor en novillas que pastorearon en S2 con 893 g/animal/día. El consumo de MS fue mayor S2 con 10,98 kg animal/día mientras el S1 presento menor consumo 7,75 kg animal/día. En conclusión, los indicadores agronómicos y productividad animal fueron mejores en S2

The use of GIS and Multi-Criteria evaluation (MCE) to determine scenarios of potential floodings in fluvial basins : study case: cuenca Guanabo, Habana city

El trabajo muestra la potencialidad que presentan los Sistemas de Información Geográfica (SIG) y la evaluación multicriterio (EMC), para determinar con precisión, la cartografía de las zonas susceptibles al desarrollo de inundaciones recurrentes en cuencas fluviales. La capacidad de análisis y manejo de la información espacial que poseen los SIG en la actualidad, conjuntamente con el procesamiento estadístico apoyados en el uso de la EMC, permiten cuantificar factores del medio natural y establecer grados de adecuación, reduciendo la subjetividad durante el procesamiento analítico. Las zonas susceptibles determinadas con el empleo de esta metodología se comparó con estudios anteriores y los resultados presentan una buena coincidencia espacial aunque ésta mejora en precisión cartográfica. Sin duda los resultados obtenidos constituyen valiosas herramientas de gestión, los cuales ayudan a la toma de decisiones en los territorios e incrementan el nivel de conocimiento para reducir los riesgos de desastres naturales.The work shows the potential that Geographic Information Systems and Multi-Criteria Evaluation (EMC) have, to determine accurately, the cartography of favorable areas to recurrent floods development in fluvial basins. The analysis and special information handling capacity that the SIGs have nowadays, together with statistic processing resting in the (EMC) use, make it possible to quantify natural resources factors and establish degrees of fitness, reducing subjectivity during analytic processing. The capable zones determined with the employment of this methodology were compared with previous studies and the result presents a good spatial coincidence though this one improves in cartographic precision. Certainly, the results obtained become valuable management tools that help territory decision making and increase knowledge level to reduce natural disasters risks.Fil: Olivera Acosta, Jorge. La Habana (Cuba). Agencia de medio ambienteFil: Morales, Gustavo Martín. La Habana (Cuba). Agencia de medio ambienteFil: García Rivero, Alberto E.. La Habana (Cuba). Agencia de medio ambienteFil: Salgado, Efrén Jaimez. La Habana (Cuba). Agencia de medio ambienteFil: López, Martin Luis. La Habana (Cuba). Agencia de medio ambienteFil: Estrada, Reinaldo. La Habana (Cuba). Agencia de medio ambienteFil: Campos Dueñas, Mario. La Habana (Cuba). Agencia de medio ambienteFil: Miravet, Bárbara Liz. La Habana (Cuba). Agencia de medio ambient

The addition of reduced glutathione to cryopreservation media induces changes in the structure of motile subpopulations of frozen-thawed boar sperm

Adding cryopreservation media with reduced glutathione (GSH) has previously been shown to maintain the motility, membrane integrity and fertilizing ability of frozen-thawed boar sperm, although the effects of GSH on good (GFE) and poor freezability (PFE) ejaculates rely upon the intrinsic ejaculate freezability. The resilience to withstand freeze-thawing procedures has previously been related to the existence of a specific distribution of motile sperm subpopulations, which differs between GFE and PFE. Thus, the main aim of this study was to determine whether the addition of GSH to freezing media has any impact on the distribution of motile sperm subpopulations in GFE and PFE. With this purpose, 18 GFE and 13 PFE were cryopreserved with or without 2 mM GSH. Sperm quality and motile subpopulations were evaluated at 30 min and 4 h post-thawing. Three subpopulations were identified and the percentages of spermatozoa belonging to the fastest and most linear subpopulation, which was referred as 'SP1', decreased over post-thawing time. Good freezability ejaculates that were cryopreserved in the presence of 2 mM exhibited a significantly higher percentage of spermatozoa belonging to SP1 than the other combinations of treatment and freezability both at 30 min (mean ± SEM: GFE-C: 16.6 ± 0.4; GFE-GSH 27.7 ± 0.6) and 4 h post-thawing (GFE-C: 7.8 ± 0.2 vs

Inhibidor de corrosión a base de amida-imidazolina-zinc

En el presente estudio, presenta sustancias orgánicas tipo amida-imidazolina y mida imidazolina modificadas con zinc sintetizadas por métodos químicos con el fin de ser utilizadas como inhibidores de corrosión. Los materiales sintetizados fueron caracterizados por técnicas electroquímicas y técnicas espectrofotométricas tales como IR y Raman. Resultados preliminares demostraron que el material sintetizado, inhibe el proceso de corrosión en 80%, como fue determinado por las curvas de polarización (pendientes de Tafel, perfiles log i versus E), indicando que el mecanismo de reacción de corrosión es modificado con respecto a los mecanismos en solución libre de inhibidor. Por otro lado, los estudios por IR y Raman indican claramente la presencia de grupos funcionales correspondientes a la sustancia orgánica sintetizada. Por 1H RMN presenta también señales de la amida-imidazolina.In this study, presents amide-type imidazoline measure organic substances and imidazoline modified zinc synthesized by chemical methods in order to use it as corrosion inhibitors. The synthesized materials were characterized by spectrophotometric techniques and electrochemical techniques such as IR and Raman. Preliminary results showed that the synthesized material, inhibits the corrosion process by 80%, as determined by the polarization curves (Tafel slopes, profiles log i versus E), indicating that the reaction mechanism of corrosion is changed from mechanisms inhibitor in free solution. Moreover, the IR and Raman studies clearly indicate the presence of appropriate functional groups to the synthesized organic substance. 1H NMR also shows signs of the amide-imidazoline

Specific LED-based red light photo-stimulation procedures improve overall sperm function and reproductive performance of boar ejaculates

The present study evaluated the effects of exposing liquid-stored boar semen to different red light LED regimens on sperm quality and reproductive performance. Of all of the tested photo-stimulation procedures, the best pattern consisted of 10min light, 10min rest and 10min of further light (10-10-10 pattern). This pattern induced an intense and transient increase in the majority of motility parameters, without modifying sperm viability and acrosome integrity. While incubating non-photo-stimulated sperm at 37°C for 90min decreased all sperm quality parameters, this reduction was prevented when the previously-described light procedure was applied. This effect was concomitant with an increase in the percentage of sperm with high mitochondrial membrane potential. When sperm were subjected to 'in vitro' capacitation, photo-stimulation also increased the percentage of sperm with capacitation-like changes in membrane structure. On the other hand, treating commercial semen doses intended for artificial insemination with the 10-10-10 photo-stimulation pattern significantly increased farrowing rates and the number of both total and live-born piglets for parturition. Therefore, our results indicate that a precise photo-stimulation procedure is able to increase the fertilising ability of boar sperm via a mechanism that could be related to mitochondrial function

Detection of Norovirus in saliva samples from acute gastroenteritis cases and asymptomatic subjects: association with age and higher shedding in stool

Norovirus infections are a leading cause of acute gastroenteritis outbreaks worldwide and across all age groups, with two main genogroups (GI and GII) infecting humans. The aim of our study was to investigate the occurrence of norovirus in saliva samples from individuals involved in outbreaks of acute gastroenteritis in closed and semiclosed institutions, and its relationship with the virus strain, virus shedding in stool, the occurrence of symptoms, age, and the secretor status of the individual. Epidemiological and clinical information was gathered from norovirus outbreaks occurring in Catalonia, Spain during 2017-2018, and stool and saliva samples were collected from affected and exposed resident individuals and workers. A total of 347 saliva specimens from 25 outbreaks were analyzed. Further, 84% of individuals also provided a paired stool sample. For GII infections, norovirus was detected in 17.9% of saliva samples from symptomatic cases and 5.2% of asymptomatic individuals. Positivity in saliva occurred in both secretors and nonsecretors. None of the individuals infected by norovirus GI was positive for the virus in saliva. Saliva positivity did not correlate with any of the studied symptoms but did correlate with age 65 years old. Individuals who were positive in saliva showed higher levels of virus shedding in stool. Mean viral load in positive saliva was 3.16 1.08 log10 genome copies/mL, and the predominance of encapsidated genomes was confirmed by propidium monoazide (PMA)xx-viability RTqPCR assay. The detection of norovirus in saliva raises the possibility of oral-to-oral norovirus transmission during the symptomatic phase and, although to a lesser extent, even in cases of asymptomatic infections

Reproductive characterization of hair ewe in the American tropics: a review part 1

Objective: to make a reproductive characterization of the hair sheep breeds in the American tropics. Design/methodology/approach: reproductive variables information was collected from scientific search engines, such as Web of Science, Redalyc, Dialnet, PubMed, SciELO and Latindex. Results: the age of puberty in ewe lambs is highly variable. Similar results were found in adult ewes regarding estrus duration and incidence, estrous cycle length, seasonal anestrus, ovulation rate, fertility, gestation, and prolificacy. Limitations on study/implications: information on reproductive variables of hair sheep breeds is poorly known or non-existent. Findings/conclusions: puberty onset in ewe lambs ranges from 175 to 335 d of age when animals weight 15 to 43 kg. The length of the estrous cycle of hair sheep in Mexico is 17 d during the autumn-winter and 21 d in spring-summer. In Brazil, it lasts 17 d in spring-summer and 18 d in autumn-winter. In the United States of America and Venezuela, the estrous cycle length was similar in both periods of the year. The estrous occurrence was 97.1% in autumn-winter and 76.5 % in spring-summer. The estrous duration ranges from 16 to 52 hours. Seasonal anestrous occurs from May to July. The ovulation rate ranges from 1 to 3 oocytes. Fertility is 80 to 100 % in temperate and 37 % in warm months. Gestation length ranges from 144 to 152 d. Prolificacy ranges from 1.0 to 2.2 offspring per ewe. The lambing interval range from 244 to 294 d.Objective: To carry out a reproductive characterization of the breeds of hair ewe in the tropical region of the Americas. Design/Methodology/Approach: A search of scientific information about the reproductive variables of breeds of hair ewe was carried out and the results were analyzed in the Web of Science, Redalyc, Dialnet, PubMed, SciELO, and Latindex databases. Results: We described and discussed the highly-variable onset of puberty in ewe lambs. Similar results were found in adult ewes regarding the duration and occurrence of the estrous, estrous cycle length, seasonal anestrous, ovulation rate, fertility, gestation, and prolificacy. Study Limitations/Implications: Information about the reproductive variables of breeds of hair ewe is poorly known or non-existent. Findings/Conclusions: The onset of puberty in 15-43 kg ewe lambs ranges from 175 to 335 d of age. The estrous cycle of hair ewe in Mexico lasts 17 d in autumn-winter and 21 d in spring-summer. In Brazil, this cycle lasts 17 d in spring-summer and 18 d in autumn-winter. In the United States of America and Venezuela, the estrous cycle length was similar in both periods of the year. The occurrence of the estrous reached 97.1 % in autumn-winter and 76.5 % in spring-summer. The duration of the estrous ranges from 16 to 52 hours. Seasonal anestrous occurs from May to July. The ovulation rate ranges from 1 to 3 oocytes. The percentage of fertility fluctuates between 80 and 100 % in temperate months and reaches 37 % in warm ones. Gestation lasts from 144 to 152 d. Prolificacy ranges from 1.0 to 2.2 offspring per ewe. The lambing interval ranges from 244 to 294 d