Extruded Aquaculture Feed: A Review

Agro-industrial by-products are processed materials that can have high protein content or other nutrients. The agro-industrial by-products are traditionally sold at low prices for animal feed consumption. These residues of the agro-industry have a high concentration of nutritional and bioactive compounds, which can be applied as fishmeal substitutes. In this chapter, it is shown how extrusion can be an alternative process for aquaculture feed production, increasing digestibility, and functional properties of the aquaculture feed, such as water stability and floatability. The thermal process during extrusion decreases the antinutritional factors present in legumes or other agro-industrial by-products, such as trypsin inhibitors and lectins. This chapter reviews research related to new protein sources that can potentially complement or substitute fishmeal for aquaculture feed. The use of bean (Phaseolus vulgaris) protein and cottonseed meal as a fishmeal substitute are shown, as well as the optimization of the extrusion process for aquaculture feed production. The incorporation of plant protein into the aquaculture production contributes to a more sustainable process. The effect of the extrusion parameters on the final product and quality are explained

"Proceso de investigación formativa en la carrera profesional de ingeniería mecánica de la facultad de ingeniería mecánica- energía de la Universidad Nacional del Callao"

En la presente investigación. Proceso de Investigación formativa, se destaca la aplicación de las estrategias pedagógicas; como resolver problemas, adecuación a formatos, normas y reglamentos de identificación de problemas, a través de los instrumentos transversales de la investigación formativa. Las estrategias pedagógicas que se realizan en el seno de los cursos universitarios, se refieren a como el docente conduce a sus alumnos en el desarrollo de sus trabajos académicos las que deben estar plasmados en cada tema del silabo de cada asignatura. Los instrumentos trasversales han sido adecuados a formatos, normas y reglamentos utilizando las ventajas que brinda el procesador de texto.Trabado de investigacio

"Tópicos iniciales de matemática para estudiantes de ingeniería con problemas con enfoque vectorial. Volumen I”

El enfoque vectorial de las definiciones, propiedades y de los ejercicios desarrollados hace que los lectores comprendan y se familiaricen rápidamente con los temas de, espacios vectoriales reales R", operaciones algebraicas con vectores, representación e interpretación grafica de vectores, independencia lineal de vectores, vectores base estándar o canónicos, aspectos importantes de los vectores como norma de un vector, paralelismo, ortogonalidad, ángulo entre vectores, vector unitario, proyección ortogonal y componente de un vector sobre otro vector constituyen los cimientos para: Primero, el estudio la recta en R2 y /23, posiciones relativas de dos rectas, transformaciones de traslación y rotación de coordenadas, traslación y rotación de ejes coordenados en R2. Segundo, el estudio de los vectores en R3, paralelismo, ortogonalidad, producto escalar, producto vectorial (propio de R3) y producto mixto. Tercero, el estudio de la recta en R3, posiciones relativas de dos rectas; rectas que se intersecan, que se cruzan, ángulo entre dos rectas, distancia entre rectas que se cruzan, distancia de un punto a una recta. Cuarto, el estudio del plano en R3, posiciones relativas de dos planos, distancia de un punto a un plano, posiciones relativas entre una recta y un plano, intersección entre una recta y un plano, distancia entre planos paralelos y proyección ortogonal de una recta sobre un plano.Trabado de investigacio

Aluminoxane co-catalysts for the activation of a bis phenoxyimine titanium (IV) catalyst in the synthesis of disentangled ultra-high molecular weight polyethylene

New activation systems for the bis[N-(3-tert-butylsalicylidene)pentafluoroanilinato] Ti (IV) dichloride catalyst (FI) for the synthesis of ultra-high molecular weight polyethylene (UHMWPE) with reduced entanglement density are explored. Together with the well-studied FI catalyst-methylaluminoxane (MAO) catalytic system, different aluminoxanes, namely polymethylaluminoxane-improved performance (PMAO), modified methylaluminoxane type 12 (MMAO12) and type 3A (MMAO3A) have been used. The catalyst activity increases with the addition of a co-catalyst modifier (2,6-di-tert-butyl-4-methylphenol, BHT). For an example when using MMAO3A as co-catalyst in combination with BHT the catalyst activity increases by tenfold. The synthesized UHMWPEs have been characterized via rheology, differential scanning calorimetry and uniaxial solid-state deformation to evaluate the influence that the different co-catalysts have on the catalyst activation and the entangled state of the polymer. Entanglement density increases when PMAO is used as a co-catalyst influencing the rheological response of the polymer melt and melting kinetics of nascent powder. Mechanical properties increase when MMAO12 is used in place of MMAO3A as co-catalyst. However, the earlier reported mechanical properties of UHMWPE synthesized using the FI/MAO are found to be better than those obtained using the co-catalysts investigated in this study

Aplicación de la técnica de la punción seca en el tratamiento del síndrome del dolor miofascial de la musculatura de la columna vertebral en pacientes del Hospital San Vicente de Paúl de la ciudad de Ibarra durante el periodo Enero a Julio del 2012

GENERAL “Evaluar la aplicación la técnica de punción seca para liberar los puntos gatillo causantes del síndrome de dolor miofascial de la musculatura de la columna vertebral en pacientes del hospital San Vicente de Paul de la ciudad de Ibarra en el periodo de enero a julio del 2012”En la actualidad la incidencia de patologías relacionadas con el dolor muscular han sido más frecuentes debido a la presencia de factores que desencadenan la patología como son el estrés, ,sobrecargas y abusos en el musculo esquelético, traumatismo directo por lo cual hemos visto necesario la implementación de tratamientos innovadores que tengan una mayor efectividad a la hora de encontrar resultados, debido a la demanda de pacientes que presentan esta patología en el Hospital San Vicente de Paul de la ciudad de Ibarra se planteó acoger esta propuesta, que nos permitió desarrollar este estudio de investigación en condiciones adecuadas. El objetivo planteado fue la evaluación de la aplicación de la técnica de punción seca para liberar puntos gatillo causantes del síndrome de dolor miofascial en los músculos paravertebrales, encontrar los factores desencadenantes de la patología por medio de este prevenir futuras reapariciones de la enfermedad. La técnica de punción seca es una técnica invasiva en la cual se utiliza una aguja de acupuntura en el sitio en donde se presenta el dolor, mediante el estímulo mecánico producido al introducir la aguja, se origina una serie de cambios fisiológicos que ayudaran a la disminución de los sintomatología. Para realizar la investigación utilizamos los tipos de investigación descriptiva, propositiva y de campo, fue de diseño no experimental y de corte transversal. Para la ejecución de la investigación se trabajó con una población de 38 pacientes que acudían al área de rehabilitación, en los horarios de 14:00 a 17:00 de lunes a viernes. Se utilizó una encuesta estructurada pre y post-diagnostica para la recolección los datos. Este trabajo de investigación determino los siguientes resultados que en el 60,53% de los pacientes atendidos se logró eliminar por completo la presencia del dolor en la zonas de la musculatura paravertebral tratada, y el 94.74% de la población estudiada obtuvo excelentes resultados eliminando la presencia de puntos gatillo miofasciales y por ende bandas tensas características principales síndrome de dolor miofascial, dando como resultado un mejor desempeño laboral y alto rendimiento en los pacientes, y por último la prevalencia de puntos gatillo miofasciales después de la aplicación de la técnica con un 5,26% de pacientes encuestado

Unique rheological response of ultrahigh molecular weight polyethylenes in the presence of reduced graphene oxide

The paper addresses the difference in electrical conductivities and rheological properties between two nanocomposites of reduced graphene oxide nanosheets (rGON) with commercial ultrahigh molecular weight polyethylene (C_PE) and a low-entanglement-density UHMWPE synthesized under controlled conditions (Dis_PE). It has been found that composites made with Dis_PE can reach conductivities at least 100 times higher than those made with C_PE on doing thermal treatment at lower temperatures. However, the difference in the electrical conductivity diminishes when both sets of samples are given a high temperature treatment. This phenomenon is attributed to the difference in morphology of the polymer matrices, for example, grain boundaries between the nascent particles. Furthermore, rheological analyses of the two sets of UHMWPE/rGON nanocomposites conclusively demonstrate differences in the interaction between polyethylene chain segments of the disentangled UHMWPE and rGON, compared to the entangled commercial UHMWPE. Both composites show minima in the storage modulus at a specific graphene composition. The strong interaction of polyethylene chains with the filler inhibits disentangled UHMWPE to achieve the thermodynamic equilibrium melt state, whereas in the commercial sample, having a broader molar mass distribution, the higher adhesion probability of the long chains to the graphene surface lowers the elastic modulus of the polymer melt. Correlation between the percolation threshold for electrical conductivity and rheological response of the composites has also been discussed

Influence of reduced graphene oxide on the rheological response and chain orientation on shear deformation of high density polyethylene

© 2016 Elsevier Ltd. All rights reserved. The rheological response of high density polyethylene/reduced graphene oxide nanoplatelets (HDPE/rGON) composites, and the influence of rGON on chain orientation and crystallization behavior after shear flow are investigated. Melt rheology reveals the presence of strong interaction between polymer chains and the filler. Above 4.0 wt % of the filler concentration, the terminal region of frequency sweep shows changes in the linear viscoelastic properties of the composites. In particular, at these high concentrations the cross-over frequency at which the transition from predominantly elastic to viscous behavior occurs significantly shifts to lower values, indicating the formation of a solid-like percolated network. A drop in G′ at high frequency (100 rad/s) is observed in the presence of the filler, and the storage modulus shows minima at filler concentration between 2.0 and 4.0 wt %. The influence of chain-filler interaction on chain orientation, and subsequent crystallization behavior after application of shear is followed by time resolved WAXD/SAXS. The orientation of the crystalline domains was quantified by the Herman's orientation factor that supports the presence of strong chain-filler interaction. The Deborah number of reptation and retraction suggests that during the applied non-linear shear, polymer chains in the composites experience mild stretch that is not significant enough to induce crystallization at the high temperature (136 °C). However, restriction imposed by the filler on the chain mobility is pronounced enough to preserve oriented state that causes anisotropy in crystallization on cooling. The enhanced orientation with increasing filler content is conclusively attributed to the strong chain-filler interaction

Development and Evaluation of an Extruded Balanced Food for Sheep Based on Cottonseed Meal <em>(Gossypium hirsutum)</em>

The objective of this research was to evaluate the effect of the content of cottonseed meal (Gossypium hirsutum) and the processing variables on the functional properties and the content of gossypol of an extruded feed for sheep (Ovis aries). The diet was balanced according to the requirements of fattening Dorper sheep breed under 1 year. The extrusion process was optimized using a surface response methodology, with four independent variables: temperature in the last heating zone (120–160°C), moisture content (14–18%), screw speed (120 rpm–180 rpm), and cottonseed meal content (9 g–27 g 100 g−1), in a single screw extruder. The optimal food had 27.25% crude protein, 4.24% crude fat, 12.21% crude fiber, 46.95% nitrogen-free extract, and 9.35% ash. The composition of essential amino acids in the optimal diet was 1.00 g kg−1 of lysine, 1.25 g kg−1 of phenylalanine, 2.04 g kg−1 of leucine, 0.87 g kg−1 of isoleucine, 0.98 g kg−1 of threonine, 1.15 g kg−1 of valine, and 0.65 g kg−1 of histidine. The fatty acids present in the highest concentration in the optimal diet were 2.14% linoleic acid, 1.11% oleic acid, and 0.81% palmitic acid. The gossypol content of the optimal diet was less than 0.1%, which ensures the safety of cottonseed meal as a protein source. The optimum conditions of the extrusion process were 120°C temperature, 120 rpm screw speed, 14.00% humidity, and 27 g 100 g−1 cottonseed meal

Prediction of Solubility and Miscibility Parameters of Bismuth-Arsenic Complex and Amorphous Mineral Compounds Using Molecular Dynamics Simulation

Bismuth is one of the most difficult impurities to remove in mining concentrates and low concentrations generate problems in silver and copper refineries. Therefore, financial penalties are established when concentrations exceed 0.05%. Some researchers had used arsenic to remove bismuth with results of up to 52% of extraction. Unfortunately, this mechanism is not yet fully understood. The objective of this research was to obtain the solubility parameters of amorphous mineral compounds, including bismuth-based compounds, through computational simulation using molecular dynamics. The composition of the mineral sample was determined by X-ray diffraction and the crystalline species were obtained and modeled using Materials Studio software. The nanostructures were optimized by an energy minimization methodology using the Broyden-Fletcher-Goldfarb-Shanno algorithm and were validated using the figure of merit equation and density. Simulations were performed using the Universal Force Field at constant pressure and temperature. The results of the minerals identified in the sample were compared with arsenic trioxide, indicating miscibility between As2O3 and Bi2O3, possible miscibility with 10 other minerals, and immiscibility with the rest. The results indicate that As2O3 can be successfully used for the removal of Bi2O3 without a negative effect on the recovery of other minerals of higher commercial value