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Caracterización Fenotípica y Molecular de Cepas de Yersinia Ruckeri Aisladas de Oncorhynchus Mykiss, del Centro Piscícola “El Ingenio” – HuancayoBueno Mendizábal, Hamilton Chen January 2012 (has links)
La demanda de trucha arco iris en nuestro país se ha incrementado significativamente en estos últimos años, por ello la industria dedicada al cultivo de esta especie también ha incrementado su número, y los que ya se dedicaban a esta actividad se han visto en la necesidad de aumentar la producción de truchas cultivadas. La enfermedad entérica de la boca roja es una de las principales enfermedades que afectan al cultivo de las truchas, generando grandes pérdidas económicas, el agente etiológico es la bacteria Yersinia ruckeri, la cual se transmite de un pez a otro por contacto y a través del agua. La presente investigación tuvo como objetivo, aislar y caracterizar a nivel fenotípico y molecular estirpes de Yersinia ruckeri en truchas arco iris obtenidas en el centro piscícola “El Ingenio” – Huancayo, para incrementar el conocimiento de la biología de este agente patológico, y relacionar las estirpes aisladas a partir de peces con sintomatología de enfermedad, con las aisladas a partir de peces sin sintomatología de enfermedad.
El presente estudio se desarrolló en el Centro Piscícola “El Ingenio”- Junin y en el laboratorio de Microbiología Molecular y Biotecnología de la UNMSM- Lima, en el año 2010. Se recolectaron peces con sintomatología de enfermedad entérica de la boca roja (EBR) y sin sintomatología de ésta, identificándose a través de pruebas bioquímicas, 34 cepas presuntivas de Y.ruckeri y confirmándose por PCR, 30 de ellas; todas las cepas identificadas pertenecen al biotipo 1. Se realizaron pruebas de susceptibilidad antimicrobiana encontrándose cepas resistentes a ácido oxolínico, cloranfenicol, tetraciclina y amoxicilina; se reporta 4 cepas con resistencia múltiple. Para el análisis genético molecular se utilizó las técnicas Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR), repetitive extragenic palindromic PCR (REP-PCR) y extragenic repeating elements PCR (BOX-PCR), determinándose variabilidad intraespecífica tanto en cepas aisladas de peces con sintomatología como en peces sin sintomatología de la EBR.
Palabras clave: Enfermedad entérica de la boca roja (EBR), Yersinia ruckeri, trucha arco
iris, caracterización fenotípica de Y. ruckeri, caracterización molecular de Y. ruckeri. / Demand for rainbow trout in our country has increased significantly in recent years, so the industry dedicated to the culture of this species has also increased its number, and those already engaged in this activity have been in need of increase production of farmed trout. The disease enteric red mouth is one of the major diseases affecting the cultivation of trout, causing major economic losses, the causative agent is the bacterium Yersinia ruckeri, which is transmitted from one fish to another by contact and by water . The present study aimed to isolate and characterize phenotypic and molecular strains of Yersinia ruckeri in rainbow trout fish obtained in the center "El Ingenio" - Huancayo, to increase knowledge of the biology of this disease agent, and relate strains isolated from fish with symptoms of disease, with those isolated from fish without symptoms of disease.
This study was to realize at the Fish Farming Center "El Ingenio" - Junin and laboratory of Molecular Microbiology and Biotechnology of San Marcos, Lima, in the 2010. Fish were collected with symptoms of enteric disease red mouth (EBR) and without symptoms of this, identified through biochemical tests, 34 strains Y.ruckeri presumptive and confirmed by PCR, 30 of them, all strains identified belong to biotype 1. Susceptibility testing was performed antimicrobial resistant strains found oxolinic acid, chloramphenicol, tetracycline, amoxicillin; 4 are reported multiple resistant strains. For molecular genetic analysis techniques used Enterobacterial repetitive intergenic consensus PCR (ERICPCR), repetitive extragenic palindromic PCR (REP-PCR) and PCR extragenic repeating elements (BOX-PCR), determining intraspecific variability in strains isolated from fish with symptoms like fish without symptoms of EBR.
Keywords: Enteric redmouth disease (ERM), Yersinia ruckeri, rainbow trout, phenotypic characterization of Y. ruckeri, molecular characterization of Y. ruckeri. / Tesis
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Genetic pathways of Lyst and exfoliation syndromeTrantow, Colleen 01 December 2009 (has links)
Human eyes with exfoliation syndrome (XFS) exhibit a distinctive pattern of iris transillumination defects that are recapitulated in Lyst mutant mice carrying the beige allele. Here I present the identification and characterization of the B6-Lystbg-J mouse model of XFS, modifiers of Lyst mediated ocular phenotypes, mechanisms of intraocular pressure (IOP) pathology related to circadian rhythms, and mechanisms of iris transillumination defects in the B6-Lystbg-J mice.
Clinical and histological analysis shows that the B6-Lystbg-J mice have multiple similarities to human XFS including: iris transillumination defects, production of an exfoliative-like material, and pronounced pigment dispersion. Despite these insults, Lyst mutation does not cause increased IOP or optic nerve damage within the context of a C57BL/6J genetic background. However, defects in the circadian rhythm regulation of IOP were identified. Sequence analysis identifies that the beige mutation is predicted to delete a single isoleucine from the WD40 domain of the LYST protein. I identified CSNK2B as a binding partner of LYST and showed that LYSTbg-J completely disrupts the interaction. CSNK2B function in regulating E-cadherin and β-catenin binding is subsequently disrupted. These results lead to a working hypothesis that aspects of the XFS phenotype involve LYST and CSNK2B pathways, likely influencing cell-cell adherens junctions.
Epistasis experiments were used to test for genetic modifiers of Lyst, which demonstrated that albino Lyst mutant mice exhibited complete rescue of Lyst-dependent iris phenotypes. In a genetic background-driven approach, a DBA/2J strain of congenic mice was created. The DBA/2J background, which harbors multiple mutations influencing melanosomal-proteins, enhanced Lyst dependent iris phenotypes. Thus, both experimental approaches implicated melanosomes, a potential source of oxidative stress, as mechanistically contributory. Supporting a contributory role of oxidative damage, Lyst mutation resulted in genetic context sensitive changes in iris lipid hydroperoxide levels, being lowest in albino and highest in DBA/2J mice. These results identified an association between oxidative damage to lipid membranes and severity of Lyst-mediated phenotypes, uncovering a new mechanism contributing to pathophysiology involving LYST. In conclusion these results demonstrate that mutation of the Lyst gene can produce ocular features of human XFS and suggests that LYST or LYST-interacting genes may contribute to XFS.
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A Study of Segmentation and Normalization for Iris Recognition SystemsMohammadi Arvacheh, Ehsan January 2006 (has links)
Iris recognition systems capture an image from an individual's eye. The iris in the image is then segmented and normalized for feature extraction process. The performance of iris recognition systems highly depends on segmentation and normalization. For instance, even an effective feature extraction method would not be able to obtain useful information from an iris image that is not segmented or normalized properly. This thesis is to enhance the performance of segmentation and normalization processes in iris recognition systems to increase the overall accuracy. <br /><br /> The previous iris segmentation approaches assume that the boundary of pupil is a circle. However, according to our observation, circle cannot model this boundary accurately. To improve the quality of segmentation, a novel active contour is proposed to detect the irregular boundary of pupil. The method can successfully detect all the pupil boundaries in the CASIA database and increase the recognition accuracy. <br /><br /> Most previous normalization approaches employ polar coordinate system to transform iris. Transforming iris into polar coordinates requires a reference point as the polar origin. Since pupil and limbus are generally non-concentric, there are two natural choices, pupil center and limbus center. However, their performance differences have not been investigated so far. We also propose a reference point, which is the virtual center of a pupil with radius equal to zero. We refer this point as the linearly-guessed center. The experiments demonstrate that the linearly-guessed center provides much better recognition accuracy. <br /><br /> In addition to evaluating the pupil and limbus centers and proposing a new reference point for normalization, we reformulate the normalization problem as a minimization problem. The advantage of this formulation is that it is not restricted by the circular assumption used in the reference point approaches. The experimental results demonstrate that the proposed method performs better than the reference point approaches. <br /><br /> In addition, previous normalization approaches are based on transforming iris texture into a fixed-size rectangular block. In fact, the shape and size of normalized iris have not been investigated in details. In this thesis, we study the size parameter of traditional approaches and propose a dynamic normalization scheme, which transforms an iris based on radii of pupil and limbus. The experimental results demonstrate that the dynamic normalization scheme performs better than the previous approaches.
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A Study of Segmentation and Normalization for Iris Recognition SystemsMohammadi Arvacheh, Ehsan January 2006 (has links)
Iris recognition systems capture an image from an individual's eye. The iris in the image is then segmented and normalized for feature extraction process. The performance of iris recognition systems highly depends on segmentation and normalization. For instance, even an effective feature extraction method would not be able to obtain useful information from an iris image that is not segmented or normalized properly. This thesis is to enhance the performance of segmentation and normalization processes in iris recognition systems to increase the overall accuracy. <br /><br /> The previous iris segmentation approaches assume that the boundary of pupil is a circle. However, according to our observation, circle cannot model this boundary accurately. To improve the quality of segmentation, a novel active contour is proposed to detect the irregular boundary of pupil. The method can successfully detect all the pupil boundaries in the CASIA database and increase the recognition accuracy. <br /><br /> Most previous normalization approaches employ polar coordinate system to transform iris. Transforming iris into polar coordinates requires a reference point as the polar origin. Since pupil and limbus are generally non-concentric, there are two natural choices, pupil center and limbus center. However, their performance differences have not been investigated so far. We also propose a reference point, which is the virtual center of a pupil with radius equal to zero. We refer this point as the linearly-guessed center. The experiments demonstrate that the linearly-guessed center provides much better recognition accuracy. <br /><br /> In addition to evaluating the pupil and limbus centers and proposing a new reference point for normalization, we reformulate the normalization problem as a minimization problem. The advantage of this formulation is that it is not restricted by the circular assumption used in the reference point approaches. The experimental results demonstrate that the proposed method performs better than the reference point approaches. <br /><br /> In addition, previous normalization approaches are based on transforming iris texture into a fixed-size rectangular block. In fact, the shape and size of normalized iris have not been investigated in details. In this thesis, we study the size parameter of traditional approaches and propose a dynamic normalization scheme, which transforms an iris based on radii of pupil and limbus. The experimental results demonstrate that the dynamic normalization scheme performs better than the previous approaches.
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Maduración Final in vitro e in vivo De Los Ovocitos De oncorhynchus mykiss “Trucha Arco Iris” walbaum, 1792.Ramos Maguiña, Eric Steve January 2002 (has links)
En los teleósteos, la hormona luteinizante inicia la maduración final de los ovocitos, etapa previa a la ovulación. El objetivo de esta tesis fue evaluar la eficiencia de la hormona gonadotrofina coriónica humana (hCG), análoga a la hormona luteinizante, para inducir la maduración final in Vitro e in Vivo de los ovocitos de Oncorhynchus mykiss “Trucha arco iris”, a partir del estadío de vesícula germinal en migración. En la maduración final in Vitro, los cultivos realizados sólo en medio Leibovitz L-15 (control) produjeron una muy reducida cantidad de ovocitos maduros. En los cultivos problema, los medios de cultivo que contenían 5UI/ml de hCG sólo con medio Leibovitz L-15 o con Leibovitz L-15 más 2% (v/v) de suero de Oncorhynchus mykiss y 5mg/ml de insulina produjeron la totalidad de ovocitos maduros a las 90 horas de cultivo, pero cuando se usó 10UI/ml de hCG en los mismos medios anteriores sólo fueron necesarias 48 horas para obtener la totalidad de ovocitos maduros. Asimismo, el análisis comparativo entre los diferentes medios problema utilizados demostró que la insulina y el suero son importantes para alcanzar el estadío de desaparición de la vesícula germinal (marcador utilizado para la maduración del ovocito in Vitro) en este pez. La ovulación mediante la maduración in Vivo fue alcanzada a las 103.2 horas con el primer tratamiento (dos dosis: 20 y 80UI de hCG/Kg de peso), mientras que los peces en los cuales fue aplicado el segundo tratamiento (dos dosis: 30 y 120UI de hCG/Kg de peso) ovularon a las 43.8 horas. Los peces control alcanzaron la maduración 31 días después de su confinamiento en el estanque de experimentación. Estos resultados demuestran la efectividad dependiente de la dosis de la gonadotrofina coriónica humana en la maduración final de los ovocitos de Oncorhynchus mykiss. / In teleosts, the luteinizing hormone begins the final oocyte maturation previous stage of ovulation. The goal of this thesis was to evaluate the efficiency of the human Chorionic Gonadotropin (hCG), luteinizing hormone analogous, to induce in Vitro and in Vivo final oocyte maturation of Oncorhynchus mykiss “Rainbow trout” come from germinal vesicle migration stage. in Vitro final oocyte maturation, the cultures achieved only into Leibovitz L-15 medium (control) showed a very less quantity of mature oocytes. In problem cultures, the culture media that only had 5IU/ml hCG into Leibovitz medium or with Leibovitz L-15 plus 2% (v/v) Oncorhynchus mykiss serum and 5mg/ml insulin produced totality of mature oocytes at 90 hours but when it was used 10UI/ml hCG with the former media were only needed 48 hours to get the totality of mature oocytes. Although the comparative analysis between the different problem media used it showed both the serum and the insulin are important to reach the germinal vesicle breakdown stage (marker used to evaluate in Vitro oocyte maturation) in this fish. The ovulation by means in Vivo maturation was reached at 103.2 hours with first treatment (two doses: 20 and 80 IU hCG/Kg body weight), while the fishes tried with second treatment (two doses: 30 and 120 IU hCG/Kg body weight) ovulated at 43.8 hours. The control fishes reached the maturation at 31 days after their confinement into experimentation pond. These results show the dose-dependent effectiveness for human Chorionic Gonadotropin in the final oocyte maturation of Oncorhynchus mykiss.
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En jämförelse av Colvard-pupillometer och mätsticka vid mätning av pupillstorlek : Samt en studie av förhållandet mellan pupillstorlek och irisfärgRoslund, Karin January 2015 (has links)
Syfte: Arbetet syftar till att jämföra de två mätmetoderna mätsticka och Colvard-pupillometer för mätning av pupillens storlek. Syftet med denna jämförelse är att undersöka om den digitala Colvard-pupillometern ger ett mer noggrant resultat än den konventionella mätstickan. Den frågeställning som ligger till grund för arbetet är: Ger mätmetoderna olika resultat? Arbetet syftar även till att undersöka förhållandet mellan pupillstorlek och irisfärg. Finns det ett samband mellan pupillstorlek och irisfärg? Metod: Mätningarna utfördes på 215 personer i Guatemala och Sverige. Mätningarna i Guatemala genomfördes under en resa med Optiker utan gränser. Endast höger öga mättes. Deltagarna ombads att fixera blicken på ett objekt på minst sex meters avstånd. Pupilldiametern mättes sedan horisontellt, först med en mätsticka med halvcirklar, sedan med Colvard-pupillometer med 0,5 mm noggrannhet. Ljusförhållandet mättes med en ljusmätare och deltagarna delades upp i två ljusnivåer där 0-600 lux blev ljusnivå 1 och 600-1200 lux blev ljusnivå 2. Ljusnivå 1 motsvarar en dämpad belysning medan ljusnivå 2 motsvarar stark belysning. Irisfärg graderas utifrån en graderingskala med 24 fotografier av olika pigmenterade iris. Resultat: För den totala populationen, Guatemala och Sverige, är bias 0,030 mm och Coefficient of Agreement 1,05 mm. I ett Bland-Altman test visades liknande resultat för de båda ljusnivåerna i både Guatemala och Sverige. Det finns en statistiskt signifikant skillnad (p<0,001) mellan pupillstorleken för ögon med mörk irisfärg och ögon med ljus irisfärg i den lägre ljusnivån. Pupillstorleken minskar med stigande ålder, r = -0,46. Slutsats: Studien visar att det inte finns någon betydande skillnad mellan att mäta pupillstorleken med Colvard-pupillometer eller med mätsticka. Båda metoderna ger likvärdiga resultat. Studien visar en statistiskt signifikant skillnad mellan ögon med ljus irisfärg och ögon med mörk irisfärg i en ljusnivå som motsvarar normal till något dämpad rumsbelysning, där ögon med ljus irisfärg har större pupillstorlek.
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"Sunk in reality" : a study of love in relation to perception of the physical world in the recent novels of Iris MurdochKadrnka, Gwendoline Jean January 1976 (has links)
No description available.
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Iris Murdoch on knowledge and freedomConlin, Alice January 2003 (has links)
In chapter one, I describe the different conceptions of self that Murdoch and Nussbaum have, and I show how these affect their depictions of human good. And I relate how each one defends the internal logic of her claims against the critique of moral relativism. I examine Iris Murdoch's conception of reality and consciousness in the distinctive way that she fuses them to a transcendent morality. / In chapter two, I turn to Murdoch's description of the journey from illusion to reality and the role of love or eros in this journey. I examine the many points of intersection between her description of the escape from selfishness and Wendy Farley's (1996) theory of how we acknowledge the other through a type of attention that she calls eros for the other . / In Chapter three, I discuss the problem that evil poses for Murdoch's moral philosophy, and how Murdoch and Farley interpret the experience of the void as yearning for relation. In the conclusion of this thesis, I present Murdoch's views on form as the consolation of human yearning. (Abstract shortened by UMI.)
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The languages of philosophy, religion, and art in the writings of Iris Murdoch /Cooper, Richard. January 1987 (has links)
This thesis develops a complex theoretical model for conceptualizing the relationships among philosophy, religion, and art and, then, examines the philosophical writings and the novels of Iris Murdoch from this perspective. The theoretical model in its most general form is based on the premiss that philosophy, religion, and art can be thought of as conventionally defined linguistic fields analogous to Wittgensteinian language-games. Relations among the linguistic fields are, in turn, analysed as exclusive ("Disparate" Model), inclusive ("Reductionist" Model), or interactional ("Dialectical" and "Tensional" Models), the latter pair being most appropriate for figurative language, the former pair for non-figurative language. The Dialectical and Tensional Models are assimilated, respectively, to Roman Jakobson's theory of metaphor and metonymy as the fundamental poles of language. Emphasis falls upon the continuum between the dialectical-metaphoric and the tensional-metonymic poles as the area in which creative, imaginative activities, such as the writing of novels or deliberation upon ethical problems, takes place. Iris Murdoch's theories of "crystalline" and "journalistic," "open" and "closed" novels and the related ways of thinking are coordinated with this continuum as a paradigm. Moreover, a creative tension is revealed in her philosophical writings between a resisted impetus towards totalizing explanations and the experience of the inherent contingency of philosophical thought. Thus, there is in Murdoch's philosophy, as in her creative prose, an exploration of the dynamics between the dialectical-metaphoric pole of thought and language and the tensional-metonymic pole, with an increasing, though never finally realized tendency towards the tensional-metonymic pole. Detailed analyses of Murdoch's aesthetic and ethical thought and of a wide selection of her novels illustrate this thesis.
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Investigating and developing a model for iris changes under varied lighting conditionsPhang, Shiau Shing January 2007 (has links)
Biometric identification systems have several distinct advantages over other authentication technologies, such as passwords, in reliably recognising individuals. Iris based recognition is one such biometric recognition system. Unlike other biometrics such as fingerprints or face images, the distinct aspect of the iris comes from its randomly distributed features. The patterns of these randomly distributed features on the iris have been proved to be fixed in a person's lifetime, and are stable over time for healthy eyes except for the distortions caused by the constriction and dilation of the pupil. The distortion of the iris pattern caused by pupillary activity, which is mainly due changes in ambient lighting conditions, can be significant. One important question that arises from this is: How closely do two different iris images of the same person, taken at different times using different cameras, in different environments, and under different lighting conditions, agree with each other? It is also problematic for iris recognition systems to correctly identify a person when his/her pupil size is very different from the person's iris images, used at the time of constructing the system's data-base. To date, researchers in the field of iris recognition have made attempts to address this problem, with varying degrees of success. However, there is still a need to conduct in-depth investigations into this matter in order to arrive at more reliable solutions. It is therefore necessary to study the behaviour of iris surface deformation caused by the change of lighting conditions. In this thesis, a study of the physiological behaviour of pupil size variation under different normal indoor lighting conditions (100 lux ~ 1,200 lux) and brightness levels is presented. The thesis also presents the results of applying Elastic Graph Matching (EGM) tracking techniques to study the mechanisms of iris surface deformation. A study of the pupil size variation under different normal indoor lighting conditions was conducted. The study showed that the behaviour of the pupil size can be significantly different from one person to another under the same lighting conditions. There was no evidence from this study to show that the exact pupil sizes of an individual can be determined at a given illumination level. However, the range of pupil sizes can be estimated for a range of specific lighting conditions. The range of average pupil sizes under normal indoor lighting found was between 3 mm and 4 mm. One of the advantages of using EGM for iris surface deformation tracking is that it incorporates the benefit of the use of Gabor wavelets to encode the iris features for tracking. The tracking results showed that the radial stretch of the iris surface is nonlinear. However, the amount of extension of iris surface at any point on the iris during the stretch is approximately linear. The analyses of the tracking results also showed that the behaviour of iris surface deformation is different from one person to another. This implies that a generalised iris surface deformation model cannot be established for personal identification. However, a deformation model can be established for every individual based on their analysis result, which can be useful for personal verification using the iris. Therefore, analysis of the tracking results of each individual was used to model iris surface deformations for that individual. The model was able to estimate the movement of a point on the iris surface at a particular pupil size. This makes it possible to estimate and construct the 2D deformed iris image of a desired pupil size from a given iris image of another different pupil size. The estimated deformed iris images were compared with their actual images for similarity, using an intensitybased (zero mean normalised cross-correlation). The result shows that 86% of the comparisons have over 65% similarity between the estimated and actual iris image. Preliminary tests of the estimated deformed iris images using an open-source iris recognition algorithm have showed an improved personal verification performance. The studies presented in this thesis were conducted using a very small sample of iris images and therefore should not be generalised, before further investigations are conducted.
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