El objetivo de este trabajo fue determinar el incremento de la precipitación pluvial sobre la prevalencia de Renibacterium salmoninarum detectado a partir de muestras de tejido (riñón y bazo) de truchas arcoíris en una piscigranja ubicada en la cuenca del valle del Mantaro. El trabajo se realizó en una piscigranja del departamento de Junín, en la provincias de Huancayo, en los meses de agosto, setiembre noviembre y febrero, durante el periodo de ciclo de lluvias 2011-2012. La fuente hídrica de la piscigranja es el rio Chiapuquio, perteneciente a la cuenca del Valle del Mantaro. Las truchas fueron colectadas al azar y provenían de ovas nacionales y americanas. Se colectaron 60 animales por muestreo, 240 truchas en total por piscigranja, considerando una prevalencia de 5%. Los peces se recolectaron en relación al ciclo de lluvias en el valle del Mantaro. Agosto (Temporada seca), Setiembre, Noviembre (Temporada de inicio de lluvias), y Febrero (Temporada de lluvias).Se extrajo el ADN de riñón y bazo mediante la técnica de fenol-cloroformo y se realizó el PCR tiempo real, no obteniéndose genoma de Renibacterium salmoninarum en ninguna de las muestras, en ninguno de las temporadas del ciclo de lluvias. Se concluye que la prevalencia de Renibacterium salmoninarum en la piscigranja de estudio es 0%, por tanto no se pudo establecer asociación entre el ciclo de lluvias y la prevalencia de Renibacterium salmoninarum. Palabras Claves: Ciclo de lluvias, cambio climático, BKD, Renibacterium salmoninarum, PCR tiempo real, Oncorhynchus mykiss / --- The aim of this study was to determine the increase in rainfall on the prevalence of Renibacterium salmoninarum detected from tissue samples (kidney and spleen) of rainbow trout in a fish farm located in the Mantaro Valley basin. The study was conducted at a fish farm in the department of Junín, in the province of Huancayo, in the months of August, September, November and February, during the rain cycle 2011-2012. The water source for the fish farm is Chiapuquio river belongs to the basin of the Mantaro Valley. The trout were randomly collected and eggs were from National and American. 60 animals were collected per sample, 240 total trout fish farm, considering a prevalence of 5%. Fish were collected in relation to the cycle of rainfall in the Mantaro Valley. August (dry season), September, November (rainy season start), and February (rainy season). DNA was extracted from kidney and spleen by phenol-chloroform technique and performed the real time PCR, yielding no Renibacterium salmoninarum genome in any of the samples, none of the rainy season cycle. We conclude that the prevalence of Renibacterium salmoninarum in fish farm study is 0%, so could not be established association between the rain cycle and prevalence of Renibacterium salmoninarum. Keywords: rain cycle, climate change, BKD, Renibacterium salmoninarum, real-time PCR, Oncorhynchus mykiss

El objetivo del presente estudio fue determinar la frecuencia de lesiones anatomohistopatológicas compatibles con alteraciones metabólicas relacionadas a energía y/o proteínas en la dieta de truchas arcoiris (Oncorhynchus mykiss) de fase juvenil. Se colectaron aleatoriamente 40 peces de una piscigranja ubicada en las provincia de Huancayo-Junín, tomándose principalmente muestras de hígado, riñón, branquias, estómago y bazo. Entre los hallazgos macroscópicos compatibles con alteraciones metabólicas observados con mayor frecuencia fue el hígado graso, caracterizado por una coloración marrón pálida en un 67.5% (27/40). En cuanto, a las lesiones histopatológicas compatibles con las alteraciones metabólicas se encontró degeneración grasa 97.5% (39/40), predominantemente en grado IV y la degeneración hialina en túbulos renales, 62.5% (25/40) y tan sólo 7.5% en glándulas gástricas de estómago. En branquias, los cambios de crecimiento como la hiperplasia (30/40), fusión (29/40) y atrofia lamelar (29/40) en un 75% y 72.5%, respectivamente, representando las lesiones de más alta frecuencia. En base a los hallazgos, se concluye que las lesiones compatibles con alteraciones metabólicas se observaron en una alta frecuencia, principalmente las relacionadas a exceso de proteína como la degeneración hialina en riñón y estómago, y la degeneración grasa en hígado por desbalance de energía. Finalmente, las lesiones en branquias sugieren una asociación entre alteraciones metabólicas y su efecto contaminante en el medio acuático. / --- The purpose of this study was to determine frequency the presentation of anothomohistopathologycal lesions compatibles with metabolic disorders related to energy and proteins in the diet of juvenile Rainbow Trout (Oncorhynchus mykiss ). Forty fish were collected randomly from the one trout hatchery, located in Huancayo-Junín, mainly taking samples of liver, kidney, gill, stomach and spleen. Between the macroscopic findings compatible with metabolic alterations observed with major frequency it was the fatty liver characterized by a brown pale coloration in 67.5% (27/40). As soon as, to the lesions histopatológicas compatible the metabolic alterations were found fat degeneration 97.5% (39/40), predominantly in grade IV and hyaline degeneration in renal tubules, 62.5% (25/40) and only 7.5% in glands gastric stomach. In gills, changes in growth such as hyperplasia (30/40), fusion (29/40) and lamellar atrophy (29/40) by 75% and 72.5% respectively, representing the highest frequency of lesions. Based on the findings, concluded that the lesions compatible the metabolic disorders were observed in a high frequency, principally related to excessive protein as hyaline degeneration in the kidney and stomach, and fatty degeneration in liver for balancing energy. Finally, the lesions on gills suggest an association between metabolic disorders and their polluting effect on the aquatic environment.

El objetivo del presente estudio fue determinar la frecuencia de lesiones anatomohistopatológicas compatibles con alteraciones metabólicas relacionadas a energía y/o proteínas en la dieta de truchas arcoiris (Oncorhynchus mykiss) de fase juvenil. Se colectaron aleatoriamente 40 peces de una piscigranja ubicada en las provincia de Huancayo-Junín, tomándose principalmente muestras de hígado, riñón, branquias, estómago y bazo. Entre los hallazgos macroscópicos compatibles con alteraciones metabólicas observados con mayor frecuencia fue el hígado graso, caracterizado por una coloración marrón pálida en un 67.5% (27/40). En cuanto, a las lesiones histopatológicas compatibles con las alteraciones metabólicas se encontró degeneración grasa 97.5% (39/40), predominantemente en grado IV y la degeneración hialina en túbulos renales, 62.5% (25/40) y tan sólo 7.5% en glándulas gástricas de estómago. En branquias, los cambios de crecimiento como la hiperplasia (30/40), fusión (29/40) y atrofia lamelar (29/40) en un 75% y 72.5%, respectivamente, representando las lesiones de más alta frecuencia. En base a los hallazgos, se concluye que las lesiones compatibles con alteraciones metabólicas se observaron en una alta frecuencia, principalmente las relacionadas a exceso de proteína como la degeneración hialina en riñón y estómago, y la degeneración grasa en hígado por desbalance de energía. Finalmente, las lesiones en branquias sugieren una asociación entre alteraciones metabólicas y su efecto contaminante en el medio acuático. / The purpose of this study was to determine frequency the presentation of anothomohistopathologycal lesions compatibles with metabolic disorders related to energy and proteins in the diet of juvenile Rainbow Trout (Oncorhynchus mykiss ). Forty fish were collected randomly from the one trout hatchery, located in Huancayo-Junín, mainly taking samples of liver, kidney, gill, stomach and spleen. Between the macroscopic findings compatible with metabolic alterations observed with major frequency it was the fatty liver characterized by a brown pale coloration in 67.5% (27/40). As soon as, to the lesions histopatológicas compatible the metabolic alterations were found fat degeneration 97.5% (39/40), predominantly in grade IV and hyaline degeneration in renal tubules, 62.5% (25/40) and only 7.5% in glands gastric stomach. In gills, changes in growth such as hyperplasia (30/40), fusion (29/40) and lamellar atrophy (29/40) by 75% and 72.5% respectively, representing the highest frequency of lesions. Based on the findings, concluded that the lesions compatible the metabolic disorders were observed in a high frequency, principally related to excessive protein as hyaline degeneration in the kidney and stomach, and fatty degeneration in liver for balancing energy. Finally, the lesions on gills suggest an association between metabolic disorders and their polluting effect on the aquatic environment.

Memoria para optar al título de Ingeniero en Alimentos / Chile es el segundo país productor de salmónidos más importante a nivel mundial. De ahí que, se convierte en el principal generador de coproductos, por sobre Noruega. Siendo el belly de la trucha arcoiris (Oncorhynchus mykiss) un coproducto desconocido, contando con escasos antecedentes de su comportamiento al conservarse refrigerado. El objetivo del presente trabajo fue determinar la pérdida de calidad funcional, química, sensorial y microbiológica del belly de trucha arcoiris (Oncorhynchus mykiss) durante su conservación en refrigeración (0º a 2º C). Se determinó la evolución de los parámetros funcionales, mediante los cuales se observó un deterioro en la funcionalidad de las proteínas presentes en el belly. También se observó el cambio de color que sufrió el belly a través del tiempo, comportándose de forma constante y sin variaciones significativas (p≥0,05). Se determinó la composición centesimal y su variación en el tiempo, obteniéndose resultados similares a aquellos presentes en la literatura. Además, el estudio contempló la determinación de pH que disminuyó en el tiempo, observándose valores de 6,62 y 6,29, al inicio y final del estudio, respectivamente. El índice de anisidina, mostró que el belly sufrió oxidación lipídica secundaria, sin embargo, este valor no superó los límites admitidos. Durante este estudio no hubo presencia de microorganismos patógenos, ni indicadores de contaminación fecal (Salmonella sp., Listeria Monocytogenes, Staphylococcus aureus), sin embargo, el recuento de aerobios mesófilos y de enterobacterias, arrojaron valores fuera de lo permitido a partir del día 10 y 24 de estudio, respectivamente. Los atributos sensoriales más sensibles para estimar el deterioro en la calidad oxidativa y textural del belly de trucha arcoiris fueron el olor típico, rancio y pútrido (crudo), elasticidad, firmeza, cohesividad y goteo. Atributos que, en conjunto con el recuento de aerobios mesófilos, sirvieron para estimar la vida útil del belly de trucha arcoiris conservado refrigerado (0º a 2º C), que fue de 12 días. De acuerdo a los resultados obtenidos mediante el análisis estadístico de los datos, se pudo determinar que existió una fuerte correlación entre los parámetros y el tiempo, y entre ellos mismos, viéndose afectada la calidad funcional, química, sensorial y microbiológica del belly de trucha arcoiris durante su conservación en refrigeración (0º a 2º C) / Chile is the second most important producer country of salmonids at worlwide level. For this reason, it turns in to the main coproducer generator, over Norway. Belly of Rainbow trout (Oncorhynchus mykiss), is an unknown coproduct, and there are very limited precedents of its behavior during chilled storaged. The aim of this study was to determined the loss of functional, chemical, sensorial and microbiology quality, during chilled storage (0ºC- 2ºC) of rainbow trout belly. Functional evolution parameters were studied, which show a deterioration in the functionality of belly proteins. Also, the belly color variation was observed trough time, behaving in a constant way and presenting no significants variations (p≥0,05) Centesimal composition and its variation in time was observed, obtaining similar results at those present in literature. The study also, contemplated pH determination, that decreased in time, being observed values from 6,62 and 6,29 at beginning and ending time of study, respectively. Anisidine index showed that belly suffered secondary lipidic oxidation, however, this value did not exceed allowed limits. During this study, neither patogens microorganisms nor faecal contamination indicators, (Salmonella sp., Listeria Monocytogenes, Staphylococcus aureus) were found in belly. Nevertheless, mesophyllic aerobic and enterobacters counts, showed values over the limits, from 10 and 24 day of study, respectively. The most sensitive sensory attributes to estimate the deterioration in the oxidating and textural quality of rainbow trout belly were typical, rancid and putrid odour (raw), elasticity, firmness, cohesiveness and dripping. Attributes that, in addition to the mesophyllic aerobic count, helped to estimate the shelf life of chilled storaged rainbow trout belly (0º to 2º C), that was 12 days. According to obtained results from statistycal analysis of data, it was possible to determine that a strong correlation existed within parameters and time, and between themselves, affecting functional, chemical, sensory and microbiologycal quality of rainbow trout belly during chilled storage (0º to 2º C)

O maior objetivo deste trabalho foi estudar os efeitos da composição dos fluxos para arco submerso sobre algumas importantes características de um metal de solda ferrítico, como composição química, microestrutura, propriedades mecânicas e geometria do cordão. Para realizar tal pesquisa, vinte oito fluxos aglomerados foram elaborados de compostos de pureza comercial e utilizados em soldagens ao aorco submerso, mantendo constante todas as demais condições de soldagem. Houve uma notável influência da composição química e do índice de basicidade dos fluxos sobre os níveis de oxig~enio, silício e manganês do metal de solda. Um modelo termodinâmico, baseado no conceito de potencial de oxigênio, foi proposto para explicar as reações gás-meta-escória ocorrendo durante a soldagem. Este modelo mostrou-se usável para as reações entre silício, oxigênio e carbono, permitindo um melhor entendimento das mesmas. A composição química do metal de solda pôde ser relacionada a sua microestrutura, através de metalografia quantitativa. Foi observado que oxigênio, silício, manganês e titânio têm grande influência sobre ela. A fase mais tenaz encontrada foi a ferrita acicular. A respeito da geometria do cordão, a sílica mostrou o efeito mais forte, com os outros compostos influenciando somente o acabamento do cordão soldado. / The main aim of this work, was to study the submerged arc welding flux composition effect on some important ferritic weld weld metal factors, such as chemical composition, microstructure, mechanical properties and bead geometry. To carry out this research, twenty eight agglomerated fluxes were laboratory - made from comercial pure compounds, and used for submerged are weldings, keeping unchanged other conditions. It was noticed a remarkable flux composition influence on the weld metal oxygen, silicon and manganese levels, as well as its relationship with the flux basicity index. Based upon the oxygen potential concept, a thermodynamic model was proposed to explain the gas-metal-slag reactions occurring during welding. This model was shown to be useful to understand reactions among silicon, oxygen and carbon. The weld metal chemical composition could be related to its microstructure, trough quantitative metallography. Also, it was noticed that oxygen, silicon, manganese and titanium have great influence on it, being acicular ferrite the most tough phase. Concerning the weld bead geometry, silica has shown the most strong effect, with others influencing only the weld bead finishing.

Tese de doutoramento. Ciências de Engenharia. 2006. Faculdade de Engenharia. Universidade do Porto

La determinación de la forma del arco inferior y la conformación del arco de trabajo es un factor preponderante en la mecánica ortodoncica como en la estabilidad post-tratamiento. Es importante comprender que ante las diferentes formas de arco que se pueden presentar, son insuficientes las formas en que se presentan los arcos preformados, siendo indispensable la necesidad de individualizar los arcos de acero para cada caso a tratar. La técnica desarrollada en este trabajo puede ser reproducida fácilmente y brinda al profesional una variada cantidad de formas diferentes de arco, esto es una ventaja sobre aquellos métodos que poseen unas pocas formas.

Zugl.: München, Techn. Univ., Diss., 2002.

No processo de soldagem TIG (Tungstênio Inerte Gás), um dos fatores que influenciam o formato do cordão de solda é o ângulo da extremidade do eletrodo. Para estudar o comportamento do arco elétrico em função da geometria de ponta do eletrodo e suas conseqüências nos cordões de solda, efetuaram-se soldagens sobre corpos de prova sem deposição de material (bead-on-plate) através de parâmetros controlados e a mecanização do processo. Parâmetros tais como vazão do gás, velocidade de avanço da tocha e comprimento do arco foram testados para verificar a atuação em conjunto com o ângulo do eletrodo. Pela análise metalográfica (macrografia) estudaram-se os perfis dos cordões de solda, verificando-se que o ângulo exerce uma influência significativa na característica do arco tensão-corrente, na largura e profundidade de penetração da solda. Para maiores ângulos de extremidade do eletrodo obteve-se aumento na penetração, diminuição da tensão e largura do cordão de solda para uma mesma intensidade de corrente. / In Gas Tungsten Arc Welding (GTAW) the weld bead shape is affected by the electrode tip angle. To study the electrical arc behavior against the electrode tip geometry and thei effects on the weld bead shape, several welding tests were performed through controlled parameters and process mechanization. Parameters such as gas flow, torch travel speed and are length were tested to verify the effect of the electrode angle on the weld bead shape. Studies on the weld bead profile through metallographical analysis showed that the vertex angle have a significant influence on the bead widht, on the weld penetration depht and on the volt-ampere characteristic. For larger tip angles and same currente intensity, an increased weld penetration, and reduction in voltage and weld bead widht was obtained.

O maior objetivo deste trabalho foi estudar os efeitos da composição dos fluxos para arco submerso sobre algumas importantes características de um metal de solda ferrítico, como composição química, microestrutura, propriedades mecânicas e geometria do cordão. Para realizar tal pesquisa, vinte oito fluxos aglomerados foram elaborados de compostos de pureza comercial e utilizados em soldagens ao aorco submerso, mantendo constante todas as demais condições de soldagem. Houve uma notável influência da composição química e do índice de basicidade dos fluxos sobre os níveis de oxig~enio, silício e manganês do metal de solda. Um modelo termodinâmico, baseado no conceito de potencial de oxigênio, foi proposto para explicar as reações gás-meta-escória ocorrendo durante a soldagem. Este modelo mostrou-se usável para as reações entre silício, oxigênio e carbono, permitindo um melhor entendimento das mesmas. A composição química do metal de solda pôde ser relacionada a sua microestrutura, através de metalografia quantitativa. Foi observado que oxigênio, silício, manganês e titânio têm grande influência sobre ela. A fase mais tenaz encontrada foi a ferrita acicular. A respeito da geometria do cordão, a sílica mostrou o efeito mais forte, com os outros compostos influenciando somente o acabamento do cordão soldado. / The main aim of this work, was to study the submerged arc welding flux composition effect on some important ferritic weld weld metal factors, such as chemical composition, microstructure, mechanical properties and bead geometry. To carry out this research, twenty eight agglomerated fluxes were laboratory - made from comercial pure compounds, and used for submerged are weldings, keeping unchanged other conditions. It was noticed a remarkable flux composition influence on the weld metal oxygen, silicon and manganese levels, as well as its relationship with the flux basicity index. Based upon the oxygen potential concept, a thermodynamic model was proposed to explain the gas-metal-slag reactions occurring during welding. This model was shown to be useful to understand reactions among silicon, oxygen and carbon. The weld metal chemical composition could be related to its microstructure, trough quantitative metallography. Also, it was noticed that oxygen, silicon, manganese and titanium have great influence on it, being acicular ferrite the most tough phase. Concerning the weld bead geometry, silica has shown the most strong effect, with others influencing only the weld bead finishing.