Effect of a polyphenol–vacuum packaging on lipid deterioration during an 18-month frozen storage of Coho Salmon (Oncorhynchus kisutch)

10 páginas, 3 tablas, 2 figuras.-- The final publication is available at www.springerlink.comA packaging system combining a polyphenolrich film and vacuum (PPRF–VP) was applied to farmed coho salmon (Oncorhynchus kisutch) muscle for an 18- month storage (−18 °C). For it, two different concentrations of polyphenol compounds (namely, p-coumaric and ferulic acids) obtained from a barley husk extract were applied (PPRF–VP conditions) and compared to vacuum packaging without polyphenol presence (vacuum control; VP condition) and to packaging in the absence of vacuum and polyphenols (control; CP condition). The study was addressed to lipid hydrolysis and oxidation development and to lipid changes related to nutritional value. Both PPRF–VP conditions provided an inhibitory effect (p< 0.05) on conjugated diene and fluorescent compound formation in frozen salmon. Compared to CP condition, vacuum packaging (PPRF–VP and VP conditions) led to lower (p<0.05) peroxide and anisidine values and to an inhibitory effect (p<0.05) on α- and γ-tocopherol losses. No effect (p>0.05) of polyphenol presence and vacuum packaging could be inferred on free fatty acid formation (hydrolysis development) and on polyunsaturated fatty acid retention (polyene index assessment). A low rancid odour development was observed in all kinds of fish samples, this being lower (p<0.05) in fish kept under vacuum (PPRF–VP and VP) conditions.Peer reviewe

The GRIN Approach: Minimizing Disruptive Behaviors and Increasing Academic Engagements

Learners cannot learn in chaos. Teachers as facilitators of learning is also the classroom manager. Numerous research and studies have correlated that positive classroom management is vital for effective teaching and learning to happen. Studies also showed that disruptive behaviors inside the classroom will be a great hindrance for learning if not addressed properly. On the other hand, studies have also shown that corporal punishment or punitive approaches to disruptive behavior have cause more harm rather than to solve the problem. These negative responses were able alleviate and not decrease the learners sense of responsibility with their actions. Inflicting fear within them is not an effective solution to stop the learners misbehaviors.

Importancia de las remesas internacionales en la economía rural de familias con migrantes procedentes del estado de Campeche

Las remesas en hogares rurales con migrantes internacionales en Campeche, México ocupan 41% del ingreso familiar, en promedio. En este artículo se presentan resultados sobre los impactos económicos de dichas remesas y se demuestra que hay vinculación entre edad de migración, capacidad económica y encadenamientos con la economía local y regional del estado. Los efectos positivos de las remesas en los ingresos familiares, en la estructura productiva, y en el valor agregado, promueven el crecimiento económico en zonas rurales con migrantes internacionales. La metodología aplicada se basó en la Matriz de Contabilidad Social aplicada a Pueblos

Evaluación de las condiciones de mezcla y su influencia sobre el cloro residual entanques de compensación de un sistema de distribución de agua potable

We performed a real scale evaluation of mixing conditions and its influence on water quality in a compensation tank of drinking-water distribution system located in the city of Cali, Colombia. The hydrodynamic study with continuous injection of tracer, and temperature and free chlorine measurements for identifying the mixing regime in the tank’s interior, residence time, thermal stratification, and chlorine variations in the stored water showed the typical characteristics of a compensation tank. We concluded that water recirculation, inadequate water exchange, low moment fluxes associated with low velocity flows, and punctual thermal stratification could lead to high water age, high residence times in the tank, inadequate mixing, and important loss of free residual chlorine. The methodology developed is suitable for evaluation and optimization of compensation tanks of drinking water distribution systems.Realizamos una evaluación a escala real de las condiciones de mezcla y su influencia en la calidad del agua en un tanque de compensación del sistema de distribución de agua potable ubicado en la ciudad de Cali, Colombia. El estudio hidrodinámico con inyección continua de marcador y mediciones de temperatura y cloro libre para identificar el régimen de mezcla en el interior del tanque, el tiempo de residencia, la estratificación térmica y las variaciones de cloro en el agua almacenada mostraron las características típicas de un tanque de compensación. Llegamos a la conclusión de que la recirculación de agua, el intercambio de agua inadecuado, los flujos de momento bajos asociados con los flujos de baja velocidad y la estratificación térmica puntual podrían conducir a una alta edad del agua, tiempos de residencia elevados en el tanque, mezcla inadecuada y pérdida importante de cloro residual libre. La metodología desarrollada es adecuada para la evaluación y optimización de tanques de compensación de sistemas de distribución de agua potable

Lipid Oxidation Inhibition in Frozen Farmed Salmon (Oncorhynchus kisutch ): Effect of Packaging

3 pages, 1 table.Coho salmon (Oncorhynchus kisutch) has recently attracted a great interest as a farmed product. This research focuses on its commercialisation as a frozen product. For it, an advanced storage technology combining vacuum and a polyphenolic rich-film was applied for a 9-months storage period (–18°C). The study was addressed to lipid hydrolysis and oxidation changes and to endogenous antioxidant content in salmon muscle. No effect of packaging conditions could be observed on free fatty acid formation. However, vacuum packaging conditions provided a partial inhibition of primary (peroxide) and secondary (anisidine value) lipid oxidation development; this inhibitory effect was accompanied by a lower tocopherol isomers loss. The employment of a film including polyphenolic compounds led to a partial inhibition of α-tocopherol breakdown and to a lower secondary (anisidine value) and tertiary (fluorescent compound formation) lipid oxidation development. A partial inhibitory effect on lipid oxidation development is concluded for the employment of a polyphenolic compound rich-film packaging when applied to farmed coho salmon.This research was carried out in the frame of the Project No. 2006 CL 0034 (2007–2008), granted by the U. Chile-CSIC Cooperation Program. Coho salmon fish was provided by Aquachile SA (Puerto Montt, Chile).Peer reviewe

The Effect of Endogenous Expression of HIV-1 gp120 on Glutamate Metabolism in Human Astrocytes

Human immunodeficiency virus (HIV) infection is a global epidemic that targets the immune system. HIV infects white blood cells and spreads throughout the entire body via blood stream and makes its way to the brain. HIV infection in the brain may lead to HIV associated neurocognitive disorders (HAND). To be able to address this problem, we have to better understand how HIV infection damages neurons. We hypothesize that gp120 causes neurotoxicity in the cells by inhibiting the conversion of glutamate to glutamine by glutaminase. As a result, glutamate concentrations will build up both inside and outside the cell causing excitatory neurotoxicity. To better understand this process, we transfected human astrocytes (U87MG cells) with mock (control), an empty vector (control), and with gp120 plasmid. Seventy-two hours post transfection, the cells were collected and run through a series of tests including SDS-PAGE/Western Blot and qRT-PCR to assess protein and mRNA levels of glutaminase and gp120. We expect production of gp120 by astrocytes to lead to a decrease in expression of glutaminase. This would inhibit the process of converting glutamate to glutamine and explain how excess of glutamate accumulates inside and outside of the cell causing neurotoxicity and cell death. In conclusion, we expect to find a direct relationship between gp120 and the glutamate metabolism in human astrocytes. Understanding the effect gp120 has on neurons will help develop more effective treatments to better fight the virus

Analysis of Ostwald ripening in Ni-rich Ni–Ti alloys by diffusion couples

"The coarsening kinetics of gamma' precipitates in Ni-rich Ni-Ti alloys are studied using a Ni-11-5 wt% Ti and pure Ni diffusion couple. The formed concentration gradient allowed to study the aging process at 1023 K (750 degrees C) in Ni-rich Ni Ti alloys with Ti content from 8-62 to 11-15 wt% Ti. In general, during the coarsening of gamma' precipitates, the experimental coarsening kinetics do not fit well to the LSW or TIDC theoretical models and anomalous behaviour of coarsening rate constant (k(r)) associated with gamma' volume-fraction is confirmed at high values.

Monitoring Physiological Responses in Giant Toad (Rhinella marina) from Coatzacoalcos, Mexico: A Comparative Study after 8 Years

The objective of this chapter is to present the results of a monitoring study carried out with physiological responses (biomarkers) in Rhinella marina (giant toad) for two different years, inhabiting the low basin of Coatzacoalcos river, one of the most contaminated regions in Mexico. A decrease in delta aminolevulinic acid dehydratase (δ-ALAD) (considered inhibition) and in the condition factor (1.2–1.5 times) found in toads of the industrial zone compared with reference organisms, each year. As for the hematological parameters, the mean corpuscular hemoglobin concentrations (MCHC), in the amphibians of industrial zone of the first sampling year show a decrease, while for the second sampling year, show an increment of 1.5 times than organisms of reference site. These effects could be associated with exposure to pollutants such as heavy metals (mainly Pb), which have been registered in different studies. This study demonstrates the usefulness of giant toads as biomonitors of contaminated sites