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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Estado situacional de Yersinia ruckeri causante de “la enfermedad entérica de la boca roja” en trucha arco iris Oncorhynchus mykiss (Walbaum, 1792) en piscigranjas de la sierra central del Perú - 2008

Sierralta Chichizola, Verónica Anamaría January 2011 (has links)
Evalúa el estado situacional del patógeno Yersinia ruckeri en cultivos intensivos de Oncorhynchus mykiss en tres piscigranjas de la sierra central del Perú durante el año 2008. Aisla y caracteriza fenotípica y serológicamente al agente causal de la ERM conducentes a la identificación del patógeno en las piscigranjas estudiadas. Evalúa el comportamiento de las cepas de Y. ruckeri frente a los antibióticos comúnmente utilizados en acuicultura mediante pruebas de antibiograma. Analiza las lesiones provocadas por Y. ruckeri en especímenes afectados, utilizando técnicas histológicas orientadas a caracterizar los signos patobiológicos más frecuentes de la ERM. Determina la frecuencia de infección de animales sintomáticos (FIAS) por Y. ruckeri causante de la ERM mediante análisis estadístico en las piscigranjas estudiadas. Identifica los factores medio ambientales que favorecen la patogénesis de la ERM a fin de sugerir en el futuro la aplicación de medidas correctivas en el manejo acuícola. / Tesis
132

Identication and Matching of Headstamp of Cartridge Using Iris Detection Algorithm

Yerragudi, Panduranga Sri Charan, Balija, Venkatesh January 2016 (has links)
Identication of cartridge is very essential in the field of forensics, military or people who collect ammunitions. The cartridges can beidentied by their headstamps.This thesis presents work on identification and matching of cartridge headstamp from the image. The Libor Masek's open source iris recognition algorithm is considered for the identification of cartridge pattern from the image.The dataset is devoleped with the cartridge headstamp patterns and matching of cartridge headstamp patterns is implemented. For matching of the cartridge pattern the Hamming distance is considered as the metric to differentiate interclass and intraclass comparisons. Variance is used as a criteria to discard the unwanted areas of the cartridge headstamp pattern.Four distinct cartridge headstamp patterns are considered. Three cartridges of each headstamp pattern are considered for intra class comparisons. The validation of the method is performed.
133

Efecto de la composición en ácidos grasos de la dieta, sobre el contenido de ácidos grasos w-3 y w-6 en el filete de trucha arcoíris (Oncorhynchus mykiss)

Caquilpan Parra, José Miguel January 2011 (has links)
Memoria para optar al título profesional de Ingeniero Agrónomo / No disponible a texto completo / El objetivo general de este ensayo fue evaluar el efecto de la modificación de la composición en ácidos grasos de la dieta, sobre el contenido de ácidos grasos ω-3 eicosapentaenoico (EPA), docosahexaenoico (DHA), ácidos grasos ω-6 Linoleico y Araquidónico; comportamiento productivo y características de calidad de canal, en trucha arcoíris (Oncorhynchus mykiss). Para modificar la composición en ácidos grasos de la dieta el aceite de soja, que es la principal fuente de grasas vegetales en las dietas comerciales actuales, fue reemplazado parcialmente por aceite de lino. Los peces con un peso vivo promedio inicial de 1126 g fueron alimentados por 10 semanas, mientras permanecían en 6 balsas-jaula en condiciones comerciales. Los peces fueron muestreados al azar cada 5 semanas para medir peso vivo, longitud horquilla, peso canal, peso vísceras, peso hígado y se identificó el sexo. Al mismo tiempo, se tomaron 9 filetes por cada tratamiento los que se mantuvieron congelados a -20°C hasta su análisis. El incremento de ácido α-linolénico en la dieta, resultó en un incremento significativo (P<0,05) de este ácido graso en el filete (0,74 vs. 0,60 control); sin embargo, no se observó diferencias significativas (P>0,05) en el contenido de EPA (0,41 vs. 0,43 control) ni DHA (0,49 vs. 0,55 control). Existió un menor contenido (P<0,05) de ácido linoleico en los filetes del grupo control (4,44 vs. 5,00 control), valores expresados como g de cada ácido graso en 100 g de filete Se concluye que la adición de un 20 % de aceite de lino en reemplazo de aceite de soja en la dieta de trucha arcoíris, disminuye significativamente el contenido de ácido linoleico y aumenta significativamente el contenido de ácido α-linolénico en el filete luego de 10 semanas de alimentación; determinando una mayor relación ω-3/ω-6 (P<0,05) en el grupo con aceite de lino (0,44±0,06 vs 0,37±0,05), sin modificar significativamente el contenido de EPA y DHA. / The objective of the present study was to evaluate the effects of changing the proportions of dietary fatty acids ω-3 EPA, DHA and ω-6 linoleic, arachidonic acid over rainbow trout (Oncorhynchus mykiss) fatty acid profile, productive performance and fillet composition. Soybean oil, the main source of vegetable fat in current commercial diets, was partially replaced for linseed oil to modify the fatty acid profile of the diet. Fish were kept in sea-cages and reared under regular commercial conditions; initial fish live weight was 1126 g and the experimental diets were supplied during 10 weeks. Fish samples were randomly taken from each cage every 5 weeks to measure live weight, fork length, carcass weight, guts and liver weight, sex was identified, at the same time 9 fish fillets were collected and frozen (-20ºC) until further analysis. The increase in dietary α-linolenic acid generated a significant (p<0.05) elevation of this fatty acid in fish fillet (0.74 vs 0.60); however, EPA and DHA levels were not affected by treatment and showed similar values when compared to the control (0.41 vs. 0.43 and 0.49 vs. 0.55). A minor contents (P < 0.05) of linoleic acid in the fillet existed of the control (4.44 vs. 5.00 control), when expressed as grams of fatty acid per 100 grams of fillet. In conclusion, replacing 20% soybean oil by linseed oil in rainbow trout diet, significantly decreased linolenic acid and significantly increased α-linolenic acid concentrations in fish fillets after 10 weeks of feeding; determining a higher ω-3 / ω-6 proportion in the fillet of fish fed linseed oil (0,44±0,06 vs 0,37±0,05), with no significant effect on EPA and DHA content.
134

Determinación de Yersinia Ruckeri y sus características lesiónales anatomo - histopatológicas en truchas Arco Iris (Oncorhynchus mykiss) en etapa pre-comercial en una piscigranja de la región Junín

Fernández Nuñez, Carlos Alberto January 2011 (has links)
El objetivo del presente trabajo fue el determinar la presencia del agente Yersinia ruckeri en la piscigranja “El Edén” y el de identificar y clasificar las lesiones anátomo histopatológicas en tejidos de trucha arco iris (Oncorhynchus mykiss) de la piscigranja “El Edén”, ubicada en la provincia Concepción a 3400 m.s.n.m. en la Región Junín. A partir de los órganos cultivados se logro aislar 11 cepas Gram negativas, 9 cepas perteneciente a las enterobacterias, de las cuales 3 fueron aracterizadas mediante pruebas bioquímicas como Yersinia ruckeri y fueron similares a las reportadas por primera vez en Idaho. Como lesiones macroscópicas se pudo observar exoftalmia unilateral 8/30 (26.66%), melanosis 4/30 (13.33%), hígado pálido 18/30 (60.00%), hígado congestionado 3/30 (10.00%), hígado con petequias 15/30 (30.00%), branquias pálidas 4/30 (13.33%), branquias hiperemicas 9/30 (30%) y del estudio hiatopatologico se evidenció congestion en bazo 14/30 (46.66%), hiperplasia del ápice de las branquias 12/30 (40.00%), hiperplasia de vellosidades del ciego 5/30 (16.66%), esporas de ictiofonus en corazón 6/30 (20.00%), necrosis en mucosa estómago 4/30 (13.33%), congestión hepática 4/30 (13.33%), hiperplasia en mucosa del intestino delgado 9/30 (38.88%) y regeneración tubular renal 9/30 (30%). Se aislaron cepas de Y. ruckeri y las lesiones en tejidos son compatibles con su infección sin embargo la frecuencia de su aislamiento es baja y existen otras bacterias diferentes a las enterobacterias que han sido aisladas incluyendo bacteria Gram positivas y que no sabemos que rol cumplen en la enfermedad de la trucha arcoíris. Palabras clave: Yersinia ruckeri, anátomo histopatológico, trucha arcoíris, enfermedad de la “boca roja entérica”. / The aim of this study was to determine the presence of the agent Yersinia ruckeri in fish farm "Eden" and to identify and classify anatomical histopathological lesions in tissues of rainbow trout (Oncorhynchus mykiss) of fish farm "El Eden" located Conception in the province at 3400 m. in Junín region. From the cultured organs was isolated 11 strains gram negative, 9 strains belonging to the Enterobacteriaceae, of which 3 were characterized by biochemical tests as Yersinia ruckeri and were similar to those reported for the first time in Idaho. As was observed macroscopic lesions unilateral exophthalmos 8/30 (26.66%), melanosis 4/30 (13.33%), liver pale 18/30 (60.00%), liver congested 3/30 (10.00%), liver petechiae 15 / 30 (30.00%), pale gills 4/30 (13.33%), gills hyperemic 9/30 (30%) and the study evidenced hiatopatologico spleen congestion in 14/30 (46.66%), hyperplasia of the apex of the gills 12 / 30 (40.00%), cecal villus hyperplasia 5/30 (16.66%), heart spores ictiofonus in 6/30 (20.00%), stomach mucosa necrosis in 4/30 (13.33%), hepatic congestion 4/30 ( 13.33%), hyperplasia in the small intestinal mucosa 9/30 (38.88%) and renal tubular regeneration 9/30 (30%). Strains were isolated from Y. ruckeri and tissue injuries are consistent with infection however the frequency of isolation is low and there are different from other bacteria that have been isolated Enterobacteriaceae bacteria including Gram positive and do not know what role they play in disease of rainbow trout. Keywords: Yersinia ruckeri, anatomical and histopathological, rainbow trout, disease of “enteric red mouth” / Tesis
135

Regeneración de blastómeros de trucha arco iris Oncorhynchus mykiss, Walbaum 1792 (Pisces : Salmonidae)

Flores Garrido, Karín Margot January 2002 (has links)
Se evaluó la capacidad regenerativa de blastómeros de Oncorhynchus mykiss de 60 horas de desarrollo utilizando vitamina A, insulina, suero 2% (v/v) de “Trucha arco iris” en estadíos previos y posteriores al desove y medio Leibovitz L-15. Primero se obtuvo la sangre de trucha anestesiando a los peces en un baño de clorobutanol (600 mg/ml). A partir de ello, la relación encontrada entre el peso del animal, el tiempo de sedación y el tiempo de recuperación fue directa y en promedio la inducción se realizó en un tiempo menor que el reportado para el anestésico. Luego, el suero de trucha obtenido fue tratado con varias temperaturas por separado, obteniéndose la inactivación de las proteínas del complemento sólo con el suero tratado a 30°C. A continuación, las concentraciones más adecuadas de vitamina A e insulina para obtener regeneración de blastómeros fueron 0.6 UI/ml de vitamina A y 0.7 UI/ml de insulina. Utilizando otros tipos de sueros, como los de mujeres grávidas y no grávidas, se estableció que ninguno de ellos son útiles para este tipo de cultivo por tanto la utilidad del suero de “Trucha arco iris” es específica en la concentración probada (2%v/v). Finalmente, cada uno de los elementos componentes del medio regeneratriz – vitamina A, insulina, suero de trucha, medio Leibovitz L-15- desempeñan diferentes roles en el proceso. En ausencia de vitamina A e insulina de manera simultánea, de vitamina A, de suero, y en presencia sólo de medio Leibovitz la capacidad regenerativa de los embriones fue casi nula a diferencia de los cultivos sin insulina. La vitamina A fue de mayor importancia debido a su rol morfógeno y la insulina jugó un papel permisivo en el proceso regenerativo. Los resultados de la ausencia del suero demostraron que este elemento es clave para mantener la adherencia entre los blastómeros del embrión de trucha mientras que el medio Leibovitz no tuvo ninguna participación en el proceso regenerativo. Se establecieron las necesidades del proceso de regeneración de blastómeros de “Trucha arco iris”, basado en la importancia de cada uno de los factores que contribuyeron en el proceso regenerativo, con concentraciones adecuadas de vitamina A e insulina necesarias para desencadenar dicho fenómeno. Su aplicación futura es de suma relevancia tanto en acuicultura, medicina veterinaria y medicina humana. / --- The regenerative capacity of the 60 hours development Oncorhynchus mykiss blastomeres was evaluated utilizing vitamin A, insulin, pre or post-spawning rainbow trout serum 2%(v/v) and medium Leibovitz L-15. First, trout blood was obtained when the fishes were anesthetized with a bath of clorobutanol at 600 mg/ml. The relationship among animal weight, sedation time and recovery time was proportionally direct and the induction is realized in a less time than the reported for the anesthetic. Then, the trout serum obtained was treated with several temperatures, the proteins complement inactivation was optimal on treated serum at 30°C. Next, the more adequate concentrations of vitamin A and insulin for blastomeres regeneration were 0.6 IU/ml vitamin A and 0.7 IU/ml insulin. Using another kind of sera such as from pregnant and non-pregnant women, it is found out that no one was useful for the culture, so the usefulness of rainbow trout serum is specific in the proven concentration (2% v/v). Finally, each regenerating medium components – vitamin A, insulin, trout serum, medium Leibovitz– have different roles into the process. Without vitamin A and insulin of simultaneous manner, without vitamin A, serum and only utilizing medium Leibovitz the embryos regenerative capacity was almost null. The vitamin A was the more important factor to its morphogenic role and the insulin played a permissive paper in the regenerative process. The results from free-serum culture showed that element is key to maintain the adherence between blastomeres of trout embryo while medium Leibovitz had no participation into regenerative process. It is established the necessities for regeneration process in rainbow trout blastomeres, based on the importance of each factors that contributed for regeneration with adequate concentrations of vitamin A and insulin to trigger this phenomenon. Its application is relevant in aquaculture, veterinary and human medicine. / Tesis
136

Stanovení flavonoidů ve vybraném sortimentu rodu Iris L. a možnosti jejich použití jako rostlinných barviv

Valešová, Barbora January 2017 (has links)
The thesis deals with the determination of the content of substances in the rhizomes and flowers of the selected variety of the genus Iris L. and the possibilities of using the iris as a dyeing plant. The literary part of the diploma thesis deals with the characteristics of the selected species and its cultivars of the genus Iris L., a description of species important in phytotherapy. Furthermore, the description of phenolic substances, flavonoids, anthocyanins, antioxidant capacities and methods of determination of these substances are described. In the practical part, the described methods are applied, the results are compared and statistical data evaluated. In the flowers of the iris, phenols, flavonoids, antioxidant capacity and anthocyanins were determined. The rhizomes determined phenols, flavonoids and antioxidant capacity. The diploma thesis also partially follows the bachelor's thesis, which compares the results of the color scale for individual samples of substances. In the diploma thesis we used to stabilize the character of metal salts (these salts in BP were not used). Several variants of the dyeing bath were used for dyeing. The filter extract of flowers in combination with vinegar, Salt, salt, edible soda, and blue rock were sampled by cold and boiling in both ways for 30 and 60 minutes. The samples were soaked in Soil Solution No. 1, which included 5 different substances (Soda, Savo, Salt, Vinegar, and Blue Scalp) and No. 2 (Blue Scalp, Vinegar and Water). As a control, samples were used that passed only the color bath without additives or pre-soaking.
137

Loss of Supersensitivity of the Cat Eye to Carbachol at Prolonged Periods After Ciliary Ganglionectomy

Colasanti, Brenda K., Hoover, Donald B. 01 January 1982 (has links)
Adult female cats (2.4-2.8 kg) underwent surgical removal of the left ciliary ganglion under pentobarbital anesthesia. Twenty-one, 560 and 616 days later, pupil size of both left and right (control) eyes was measured in response to progressively increasing doses of carbachol applied topically. By 21 days after denervation, ganglionectomized eyes showed marked supersensitivity to the miotic effects of pilocarpine and carbachol. By 560 days, however, responsiveness of the denervated eyes to lower and intermediate doses of carbachol was the same as that of contralateral control eyes, while responsiveness to higher doses was significantly reduced. Responsiveness to both lower and higher doses of carbachol was significantly less than that of the controls on the 616th day. Ganglionectomized eyes showed no pupillary response to light 14, 562, or 620 days after surgery. Histochemical analysis of iris tissue collected from eyes of these cats 720 days after ganglion removal revealed an almost complete absence of acetylcholinesterase-containing nerve fibers on the denervated side. These findings indicate that the return to normal or lower sensitivity to carbachol of denervated eyes at prolonged periods after ciliary ganglion removal is not due to significant cholinergic reinnervation of the iris sphincter muscle.
138

A Multi-stage Non-cooperative Iris Recognition Approach with Enhanced Template Security

Yang, Kai January 2011 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Biometrics identi es/veri es a person using his/her physiological or behavioral characteristics. It is becoming an important ally for law enforcement and homeland security. Among all the biometric modalities, iris is tested to be the most accurate one. However, most existing methods are not designed for non-cooperative users and cannot work with o -angle or low quality iris images. In this thesis, we propose a robust multi-stage feature extraction and matching approach for non-cooperative iris recognition. We developed the SURF-like method to extract stable feature points, used Gabor Descriptor method for local feature description, and designed the multi- stage feature extraction and matching scheme to improve the recognition accuracy and speed. The related experimental results show that the proposed method is very promising. In addition, two template security enhanced schemes for the proposed non- cooperative iris recognition are introduced. The related experimental results show that these two schemes can e ectively realize cancelability of the enrolled biometric templates while at the same time achieving high accuracy.
139

Human iris categorization using artificial neural networks

Mou, Duxing 01 January 2013 (has links) (PDF)
Image categorization is often performed manually, which can be a time consuming and a very difficult process, especially for human iris images. Previous researchers have been working on predicting ethnicity from texture features of iris images using other methods. This thesis is one of the the first to present a solution of iris image categorization using artificial neural networks, specifically for human iris images with discernible and complicated textures. The work will allow users to quickly and automatically categorize human iris images by using supervised and unsupervised learning algorithms. Contributions of this solution include a fast and accurate way to apply iris matching and solve the time consuming problems. The solution aims to find efficient and appropriate artificial neural network algorithms that can categorize iris images based on texture features. Detailed algorithms, specific techniques, performance analysis, limitations and future work will be also provided in this thesis.
140

Analysis of Near-Infrared Phase Effects on Biometric Iris Data

Stevenson, Brady Roos 07 December 2006 (has links) (PDF)
The purpose of this research is to ascertain potential iris scan data variations from near infrared waves derived from fluorescent illumination. Prior studies of iris data variances from infrared wave interference of halogen, incandescent, and sunlight with iris cameras suggest that similar changes may exist under near infrared wavelengths from fluorescent light. The concern is that the fluorescent energy emission may interfere with the near infrared detection of an iris camera. An iris camera is used to measure human eye characteristics known as biometrics. If such infrared emission is statistically significant, then it can alter the validity of the iris scan data. The experiment utilized nine hundred forty-five (945) scans from sixty-three (63) subjects. Measured results showed increased heat from ambient fluorescent illumination does not statistically alter the biometric readings of human eyes. The test results fail to reject that data loss will not occur as heat is increased in the ambient fluorescent light source.

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