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Efecto inmunoestimulantes de una dieta suplementada con paredes celulares de una cepa nativa de Saccharomyces cerevisiae, en juveniles de Oncorhynchus mykiss (trucha arcoíris)Aguilar Luis, Miguel Angel January 2014 (has links)
Publicación a texto completo no autorizada por el autor / Señala que la acuicultura es el sector productivo de la alimentación que crece más rápidamente en el mundo. En Peru, la Oncorhynchus mykiss (trucha arcoíris) es una de las especies comerciales más explotadas y el principal problema en su crianza es la susceptibilidad que presentan los estadios juveniles a enfermedades propias de animales en cautiverio. Por ello, hay un creciente interés en el manejo de las dietas de los peces con productos de origen natural para mejorar su inmunidad, aumentar su supervivencia e incrementar la producción. El objetivo fue determinar el efecto inmunoestimulante de las paredes celulares de Saccharomyces cerevisiae nativa, como suplemento dietario en juveniles de Oncorhynchus mykiss (trucha arcoíris). Se suplementó el alimento comercial con paredes celulares obtenidas mediante choque térmico (WC1) y autolisis (WC2). Después de dos semanas de aclimatación, dos grupos de truchas (n=25) fueron alimentadas con las dietas experimentales WC1 y WC2, mientras que el grupo control (n=25) fue alimentado con pienso comercial. Luego de diez semanas de alimentación, se analizó la actividad de la lisozima, la actividad hemolítica del complemento, la capacidad fagocítica y la explosión respiratoria en leucocitos de riñón anterior. Las dietas suplementadas con paredes celulares de levadura nativa WC1 y WC2 incrementaron significativamente los parámetros de la respuesta inmune innata de los grupos experimentales respecto al grupo control (p<0.05). Entre las dietas WC1 y WC2 no se encontraron diferencias significativas (p>0.05). Se concluye que las paredes celulares de Saccharomyces cerevisiae nativa incorporadas en la dieta de truchas juveniles mejoran sustancialmente la inmunidad innata. / Tesis
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Digestibilidad de grano de lupino (Lupinus albus), grano de arveja (Pisum sativum) y torta de raps (Brassica napus), y su efecto sobre el crecimiento, eficiencia del alimento y composición de la carcasa en juveniles de trucha arcoíris (Oncorhynchus mykiss)Román Ramírez, David Ramiro January 2016 (has links)
Tesis para optar al Título Profesional de Ingeniero Agrónomo y al Grado de Magister en Ciencias de la Acuicultura / La acuicultura ha experimentado un gran crecimiento, lo que conlleva una gran demanda
por harina de pescado, principal ingrediente proteico en la alimentación de especies
carnívoras. Este vital insumo es cada vez más escaso debido a la sobre explotación
pesquera, haciéndolo el más costoso dentro de la ración, al mismo tiempo, está asociado
con un importante exceso de nutrientes que representa un potencial contaminante de los
recursos hídricos en los sistemas de cultivo. El uso de proteínas vegetales como alternativa,
es crucial para el crecimiento sustentable del sector acuícola, orientando la investigación
hacia el uso eficiente de este tipo de proteínas. En este contexto, la presente investigación
tuvo como objetivo evaluar la digestibilidad de granos de lupino (Lupinus albus) y arveja
(Pisum sativum) descascarados y torta de raps (Brasica napus), y en una segunda etapa,
evaluar diferentes inclusiones sobre el crecimiento, eficiencia del alimento y composición
de la carcasa en juveniles de trucha arcoíris (Oncorhynchus mykiss). El ensayo de
digestibilidad in vivo se inició con truchas de 24,9 ± 0,4 g. las dietas se formularon en
relación a una dieta de referencia con harina de pescado, donde se sustituyó un 30 % de la
dieta referencia por los ingredientes a evaluar; en una segunda etapa se realizó un ensayo
que duró 9 semanas con truchas de 37,1 ± 3,6 g, donde se evaluó el efecto de la inclusión
de harinas de grano de lupino (15, 25, 35 %), grano de arveja (5, 15, 25 %) y torta de raps
(10, 20, 30 %) sobre el comportamiento productivo y composición de la carcasa.
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Ariadne’s Thread: Women and Labyrinths in the Fiction of A.S. Byatt and Iris MurdochTomazic, Elizabeth Mary, res.cand@acu.edu.au January 2005 (has links)
This thesis is an investigation of the journeys towards a sense of identity or selfhood, achieved through honest and accurate appreciation of the lives of others, made by several female characters in the fiction of A.S. Byatt and the late Iris Murdoch. I believe that because Byatt and Murdoch value literature as a serious business that teaches as well as entertains, their writing can play a significant role in illuminating the lives of women by means of its portrayal of the resolution of women’s struggles. Women’s lives, despite the rise of feminism, are still not equitable. While many women strive to attain a balance of independence and intimacy – what Thelma Shinn calls a “meronymic” relationship – and connection within community, many do not succeed in this endeavour. The numerous challenges they face are difficult and confronting, and the stories of their efforts resemble journeys through a labyrinth or maze. Byatt acknowledges Murdoch as her literary mother, frequently citing Murdoch’s belief in the ability of literature to improve human life. While Byatt and Murdoch are interested in what characters learn about their relations to others and the world, they make it clear that characters are constructs, not real people. Yet their fiction is an ongoing exploration of the nature of reality and the nature of selfhood, particularly that of women. According to feminist theories, women are more constrained than men, and are therefore the focus of this study, but their experience of constraint is a more complex matter than experience of mere undifferentiated oppression, and is better represented by the structure of the labyrinth than that of the simple, linear journey. I agree with Byatt’s and Murdoch’s view of the importance of fiction as a means of commenting on human relationships, particularly with the notion of the need for connection within community. The labyrinth, together with the Bildungsroman, provides a paradigm for the complex experiences of Byatt’s and Murdoch’s female characters. All the characters in this study struggle to flee from restraint, seek purpose and agency in the world through interaction with others, and escape a feminised Plato’s Cave by learning to see more accurately, and all but one emerge from the maze into an autonomous and independent existence in community with others.
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Iris recognition using standard camerasHolmberg, Hans January 2006 (has links)
<p>This master thesis evaluates the use of off-the-shelf standard cameras for biometric identification of the human iris. As demands on secure identification are constantly rising and as the human iris provides with a pattern that is excellent for identification, the use of inexpensive equipment could help iris recognition become a new standard in security systems. To test the performance of such a system a review of the current state of the research in the area was done and the most promising methods were chosen for evaluation. A test environment based on open source code was constructed to measure the performance of iris recognition methods, image quality and recognition rate.</p><p>In this paper the image quality of a database consisting of images from a standard camera is assessed, the most important problem areas identified, and the overall recognition performance measured. Iris recognition methods found in literature are tested on this class of images. These together with newly developed methods show that a system using standard equipment can be constructed. Tests show that the performance of such a system is promising.</p>
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Towards Template Security for Iris-based Biometric SystemsFouad, Marwa 18 April 2012 (has links)
Personal identity refers to a set of attributes (e.g., name, social insurance number, etc.) that are associated with a person. Identity management is the process of creating, maintaining and destroying identities of individuals in a population. Biometric technologies are technologies developed to use statistical analysis of an individual’s biological or behavioral traits to determine his identity. Biometrics based authentication systems offer a reliable solution for identity management, because of their uniqueness, relative stability over time and security (among other reasons). Public acceptance of biometric systems will depend on their ability to ensure robustness, accuracy and security. Although robustness and accuracy of such systems are rapidly improving, there still remain some issues of security and balancing it with privacy. While the uniqueness of biometric traits offers a convenient and reliable means of identification, it also poses the risk of unauthorized cross-referencing among databases using the same biometric trait. There is also a high risk in case of a biometric database being compromised, since it’s not possible to revoke the biometric trait and re-issue a new one as is the case with passwords and smart keys. This unique attribute of biometric based authentication system poses a challenge that might slow down public acceptance and the use of biometrics for authentication purposes in large scale applications.
In this research we investigate the vulnerabilities of biometric systems focusing on template security in iris-based biometric recognition systems. The iris has been well studied for authentication purposes and has been proven accurate in large scale applications in several airports and border crossings around the world. The most widely accepted iris recognition systems are based on Daugman’s model that creates a binary iris template. In this research we develop different systems using watermarking, bio-cryptography as well as feature transformation to achieve revocability and security of binary templates in iris based biometric authentication systems, while maintaining the performance that enables widespread application of these systems. All algorithms developed in this research are applicable on already existing biometric authentication systems and do not require redesign of these existing, well established iris-based authentication systems that use binary templates.
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Palmprint Identification Based on Generalization of IrisCodeKong, Adams 22 January 2007 (has links)
The development of accurate and reliable security systems is a matter of wide interest, and in this context biometrics is seen as a highly effective automatic mechanism for personal identification. Among biometric technologies, IrisCode developed by Daugman in 1993 is regarded as a highly accurate approach, being able to support real-time personal identification of large databases. Since 1993, on the top of IrisCode, different coding methods have been proposed for iris and fingerprint identification. In this research, I extend and generalize IrisCode for real-time secure palmprint identification.
PalmCode, the first coding method for palmprint identification developed by me in 2002, directly applied IrisCode to extract phase information of palmprints as features. However, I observe that the PalmCodes from the different palms are similar, having many 45o streaks. Such structural similarities in the PalmCodes of different palms would reduce the individuality of PalmCodes and the performance of palmprint identification systems. To reduce the correlation between PalmCodes, in this thesis, I employ multiple elliptical Gabor filters with different orientations to compute different PalmCodes and merge them to produce a single feature, called Fusion Code. Experimental results demonstrate that Fusion Code performs better than PalmCode. Based on the results of Fusion Code, I further identify that the orientation fields of palmprints are powerful features. Consequently, Competitive Code, which uses real parts of six Gabor filters to estimate the orientation fields, is developed. To embed the properties of IrisCode, such as high speed matching, in Competitive Code, a novel coding scheme and a bitwise angular distance are proposed. Experimental results demonstrate that Competitive Code is much more effective than other palmprint algorithms.
Although many coding methods have been developed based on IrisCode for iris and palmprint identification, we lack a detailed analysis of IrisCode. One of the aims of this research is to provide such analysis as a way of better understanding IrisCode, extending the coarse phase representation to a precise phase representation, and uncovering the relationship between IrisCode and other coding methods. This analysis demonstrates that IrisCode is a clustering process with four prototypes; the locus of a Gabor function is a two-dimensional ellipse with respect to a phase parameter and the bitwise hamming distance can be regarded as a bitwise angular distance. In this analysis, I also point out that the theoretical evidence of the imposter binomial distribution of IrisCode is incomplete. I use this analysis to develop a precise phase representation which can enhance iris recognition accuracy and to relate IrisCode and other coding methods. By making use of this analysis, principal component analysis and simulated annealing, near optimal filters for palmprint identification are sought. The near optimal filters perform better than Competitive Code in term of d’ index.
Identical twins having the closest genetics-based relationship are expected to have maximum similarity in their biometrics. Classifying identical twins is a challenging problem for some automatic biometric systems. Palmprint has been studied for personal identification for many years. However, genetically identical palmprints have not been studied. I systemically examine Competitive Code on genetically identical palmprints for automatic personal identification and to uncover the genetically related palmprint features. The experimental results show that the three principal lines and some portions of weak lines are genetically related features but our palms still contain rich genetically unrelated features for classifying identical twins.
As biometric systems are vulnerable to replay, database and brute-force attacks, such potential attacks must be analyzed before they are massively deployed in security systems. I propose projected multinomial distribution for studying the probability of successfully using brute-force attacks to break into a palmprint system based on Competitive Code. The proposed model indicates that it is computationally infeasible to break into the palmprint system using brute-force attacks. In addition to brute-force attacks, I address the other three security issues: template re-issuances, also called cancellable biometrics, replay attacks, and database attacks. A random orientation filter bank (ROFB) is used to generate cancellable Competitive Codes for templates re-issuances. Secret messages are hidden in templates to prevent replay and database attacks. This technique can be regarded as template watermarking. A series of analyses is provided to evaluate the security levels of the measures.
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Palmprint Identification Based on Generalization of IrisCodeKong, Adams 22 January 2007 (has links)
The development of accurate and reliable security systems is a matter of wide interest, and in this context biometrics is seen as a highly effective automatic mechanism for personal identification. Among biometric technologies, IrisCode developed by Daugman in 1993 is regarded as a highly accurate approach, being able to support real-time personal identification of large databases. Since 1993, on the top of IrisCode, different coding methods have been proposed for iris and fingerprint identification. In this research, I extend and generalize IrisCode for real-time secure palmprint identification.
PalmCode, the first coding method for palmprint identification developed by me in 2002, directly applied IrisCode to extract phase information of palmprints as features. However, I observe that the PalmCodes from the different palms are similar, having many 45o streaks. Such structural similarities in the PalmCodes of different palms would reduce the individuality of PalmCodes and the performance of palmprint identification systems. To reduce the correlation between PalmCodes, in this thesis, I employ multiple elliptical Gabor filters with different orientations to compute different PalmCodes and merge them to produce a single feature, called Fusion Code. Experimental results demonstrate that Fusion Code performs better than PalmCode. Based on the results of Fusion Code, I further identify that the orientation fields of palmprints are powerful features. Consequently, Competitive Code, which uses real parts of six Gabor filters to estimate the orientation fields, is developed. To embed the properties of IrisCode, such as high speed matching, in Competitive Code, a novel coding scheme and a bitwise angular distance are proposed. Experimental results demonstrate that Competitive Code is much more effective than other palmprint algorithms.
Although many coding methods have been developed based on IrisCode for iris and palmprint identification, we lack a detailed analysis of IrisCode. One of the aims of this research is to provide such analysis as a way of better understanding IrisCode, extending the coarse phase representation to a precise phase representation, and uncovering the relationship between IrisCode and other coding methods. This analysis demonstrates that IrisCode is a clustering process with four prototypes; the locus of a Gabor function is a two-dimensional ellipse with respect to a phase parameter and the bitwise hamming distance can be regarded as a bitwise angular distance. In this analysis, I also point out that the theoretical evidence of the imposter binomial distribution of IrisCode is incomplete. I use this analysis to develop a precise phase representation which can enhance iris recognition accuracy and to relate IrisCode and other coding methods. By making use of this analysis, principal component analysis and simulated annealing, near optimal filters for palmprint identification are sought. The near optimal filters perform better than Competitive Code in term of d’ index.
Identical twins having the closest genetics-based relationship are expected to have maximum similarity in their biometrics. Classifying identical twins is a challenging problem for some automatic biometric systems. Palmprint has been studied for personal identification for many years. However, genetically identical palmprints have not been studied. I systemically examine Competitive Code on genetically identical palmprints for automatic personal identification and to uncover the genetically related palmprint features. The experimental results show that the three principal lines and some portions of weak lines are genetically related features but our palms still contain rich genetically unrelated features for classifying identical twins.
As biometric systems are vulnerable to replay, database and brute-force attacks, such potential attacks must be analyzed before they are massively deployed in security systems. I propose projected multinomial distribution for studying the probability of successfully using brute-force attacks to break into a palmprint system based on Competitive Code. The proposed model indicates that it is computationally infeasible to break into the palmprint system using brute-force attacks. In addition to brute-force attacks, I address the other three security issues: template re-issuances, also called cancellable biometrics, replay attacks, and database attacks. A random orientation filter bank (ROFB) is used to generate cancellable Competitive Codes for templates re-issuances. Secret messages are hidden in templates to prevent replay and database attacks. This technique can be regarded as template watermarking. A series of analyses is provided to evaluate the security levels of the measures.
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Skolmisslyckande - en fråga om vårt samhälles syn på människors värde? : Normer och värderingar i svensk skolmiljöEkeroth, Ammi January 2006 (has links)
Denna didaktiskt inriktade C-uppsats i etik tar upp elevers skolmisslyckande satt i förhållande till skolans styrdokument, lärares yrkesetik samt vårt samhälles syn på människors värde. Syftet med uppsatsen är att utifrån Iris Marion Youngs teori kring förtryck samt Harald Ofstads teori kring styrka och svaghet, ur ett etiskt/moraliskt perspektiv, söka efter svar på följande frågeställningar: Kan elever i svensk skola anses vara förtryckta enligt Youngs teori om förtryck? Kan man inom svensk skola finna tendenser till ett sådant förakt för svaghet som Ofstad diskuterar? Vilka bakomliggande strukturella förklaringar kan man utifrån dessa teorier finna till varför vissa lärare i svensk skola medvetet eller omedvetet orsakar vissa elevers känsla av att vara kränkta, misslyckade och osynliggjorda såsom uppsatsens källmaterial påvisar? Metoden består av en etisk analys av kvalitativt empiriskt källmaterial. Källmaterialet, som bygger på delar av en doktorsavhandling i filosofi författad av Carina Henriksson, analyseras med hjälp av analysverktyg skapade utifrån Youngs teori kring förtryck samt Ofstads teori kring styrka och svaghet. Slutsatsen man kan dra utifrån analyserna visar att vissa elever i svensk skola kan anses vara förtryckta samt att man inom svensk skola kan finna tendenser till förakt för svaghet. Analyserna visar även att de bakomliggande strukturella förklaringar man kan finna till detta förtryck samt förakt för svaghet handlar om traditioner som genom historiens gång blivit allmänt vedertagna och därmed normativa, trots att de motsäger de etiska principer vårt samhälle sägs bygga på, principer man kan finna i bland annat skolans värdegrund samt lärares yrkesetiska principer.
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Reducing the activation of the IRIS reactor building using the SCALE/MAVRIC methodologyMcKillop, Jordan M. 20 November 2009 (has links)
The main objective of this research is: (1) to develop a model and perform numerical simulations to evaluate the radiation field and the resulting dose to personnel and activation of materials and structures throughout the IRIS nuclear power plant, and (2) to confirm that the doses are below the regulatory limit, and assess the possibility to reduce the activation of the concrete walls around the reactor vessel to below the free release limit.
IRIS is a new integral pressurized water reactor (PWR) developed by an international team led by Westinghouse with an electrical generation capacity of 335 MWe and passive safety systems. Its design differs from larger loop PWRs in that a single building houses the containment as well as all the associated equipment including the control room that must be staffed continuously. The resulting small footprint has positive safety and economic implications, and the integral layout provides additional shielding and thus the opportunity to significantly reduce the activation, but it also leads to significantly more challenging simulations.
The difficulty in modeling the entire building is the fact that the source is attenuated over 10 orders of magnitude before ever reaching the accessible areas. For an analog Monte Carlo simulation with no acceleration (variance reduction), it would take many processor-years of computation to generate results that are statistically meaningful. Instead, to generate results for this thesis, the Standardized Computer Analyses for Licensing Evaluation (SCALE) with the package Monaco with Automated Variance Reduction using Importance Calculations (MAVRIC) will be used. This package is a hybrid methodology code where the forward and adjoint deterministic calculations provide variance reduction parameters for the Monte Carlo portion to significantly reduce the computational time.
Thus, the first task will be to develop an efficient SCALE/MAVRIC model of the IRIS building. The second task will be to evaluate the dose rate and activation of materials, specifically focusing on activation of concrete walls around the reactor vessel. Finally, results and recommendations will be presented.
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Efecto ecotoxicológico de los detergentes biodegradables en la trucha "arco iris" Oncorhynchus mykiss (Walbaum, 1792), en el Centro Piscícola "El Ingenio"-HuancayoLeón Llanos, Miguel Antonio January 2006 (has links)
Se estudió el efecto ecotoxicológico, en tres niveles de dureza total de agua, del dodecil benceno sulfonato de sodio (DBSS) y del alquil aril sulfonato de sodio (AASS), ingredientes activos principales de dos detergentes comerciales biodegradables, en el Centro de Producción “El Ingenio”, Huancayo - Perú, empleando la “trucha arco iris” Oncorhynchus mykiss WALBAUM, 1792 como herramienta para la evaluación de riesgo ambiental. Se trabajó en total con 1440 alevines que contaban con 7 días después de haber absorbido el saco vitelino, los que se acondicionaron por una semana hasta la ejecución de los bioensayos, al iniciar los ensayos de toxicidad se realizó una biometría presentando una talla promedio de 26.8 mm y un peso medio de 0.19 g. Se reporta que el valor de la concentración letal media (CL50) a 96 horas de exposición fue en promedio 13.91 mg L-1 y 13.86 mg L-1 para DEISS y AASS respectivamente, no existiendo diferencia significativa entre los porcentajes de mortalidad de los 2 detergentes evaluados en los tres niveles de dureza de agua. El cociente de riesgo (RQ) en ambos detergentes es inferior a 1 considerando baja la probabilidad que ocasionen daño en el ambiente. / It has been studied the ecotoxicological effect, on three levels of water total hardness, and dodecil benzene sulphonate sodium (DBSS) and alquil aril sulphonate sodium (AASS), principal active ingredients of two commercial biodegradation detergents, in the Producction Center “El Ingenio”, Huancayo - Perú, using the “rainbow trout Oncorhynchus mykiss WALBAUM, 1792 as tool for evaluation the environmental risk. It had been used 1440 alevines of 7 days after absorbing the vitellum sack, whose it conditioned by a week until the execution of bioassays. At beginning the toxicity tests, it has realized a biometry reaching an average length of 26.8 mm and average weight of 0.19 g. It has reported that value of average lethal concentration (CL50) of 96 exposure hours was 13.91 mg L-1 and 13.86 mg L-1 for DBSS and AASS, respectively; there are not significant differences between the mortality percentage of detergent assessed on three levels of water hardness. The risk quotient (RQ) in both detergents is lower than 1 considering a low probability that they cause damage on the environment.
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