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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.
11

Desarrollo de un Circuito Genético Sintético Conformado por el Gen de la Proteína Verde Fluorescente (GFP) y el Promotor psp de Escherichia coli

Tueros Farfán, Felipe Gonzalo January 2015 (has links)
El aumento de la actividad minera en el Perú hace necesario el desarrollo de tecnologías rápidas y económicas de detección de contaminantes para su monitoreo y control. Implementando conocimientos de biología molecular y de la regulación génica podemos construir un circuito genético sintético que posibilite el monitoreo de sustancia toxicas que generen estrés oxidativo como son los compuestos cianurados. El objetivo de esta investigación es desarrollar un circuito genético sintético conformado por el promotor de la proteína del shock por fagos (psp) de Escherichia coli y las secuencia codificante del gen de la proteína verde fluorescente (GFP). La construcción de dicho circuito se logró usando estrategias de clonamiento por topoisomerasas y clonamiento clásico con enzimas de restricción, se usó la reacción en cadena de la polimerasa (PCR) para confirmar que todos los segmentos del circuito estén presentes en el vector. Los estudios preliminares de la actividad del nuevo circuito se realizaron transformando genéticamente células competentes de E. coli. La observación de dichas bacterias muestra una expresión de GFP continua, lo que indica que el circuito sintético está siendo activado sin estar en presencia de agentes de estrés oxidativo, lo que suponía una posible interacción con otros sistemas de regulación de estrés en la célula. Due to the increase of mining activity in Peru new technologies that can detect and monitor hazardous pollutants in a faster and cheaper way must be developed. Implementing molecular biology knowledge about genetic regulation we are able to construct a synthetic genetic circuit that can allow the monitoring of toxic substances that generate oxidative stress such us cyanide compounds. The objective of this research is to develop a synthetic genetic circuit from the promoter of the phage shock protein operon from E. coli and the complementary DNA of the green fluorescent gene (GFP). The construction of the circuit was achieved using classic cloning strategies with restriction enzymes and also more advanced strategies such us topoisomerase cloning, the polymerase chain reaction (PCR) was used to confirm the presence of all the desire segments in the vector. Preliminary studies of the circuit activity were carried out by genetically transforming competent E. coli cells. The observation of the bacteria shows a continuous expression of GFP without any inducer, this indicates that the synthetic circuit is being activated through a possible interaction with other stress response pathway.
12

Investigação da cilidrospermopsina e PSPs em amostras de águas superficiais no Estado de São Paulo (OU) Investigação da presença de cilindrospermopsina e saxitoxinas em amostras de águas superficiais no Estado de São Paulo / Cylindrospermopsin and Saxitoxins in superficial water samples Investigation in São Paulo State

Zajac, Meron Petro 09 November 2006 (has links)
O crescimento desordenado das cidades tem trazido à tona problemas de saneamento e degradação dos recursos naturais, entre eles a água. O despejo de efluentes domésticos e industriais têm ocasionado a eutrofização dos mananciais, culminando com a proliferação dos fitoplânctons. Esta proliferação tem chegado ao ponto, em certos momentos, de acarretar episódios de floração de algas. Entre os organismos fitoplanctônicos que se desenvolvem no ambiente, estão as cianobactérias, com vários gêneros capazes de produzir diversas cianotoxinas, tais como as microcistinas, anatoxinas, cilindrospermopsinas (CY), saxitoxinas (PSPs), entre outras. Com o aumento da freqüência dos episódios de floração de algas, a probabilidade da ocorrência destas toxinas também aumenta. Como conseqüência disto e devido às exigências legais, os corpos dágua devem ser monitorados para garantir a qualidade da água para consumo humano. Com vistas ao monitoramento da presença das cianotoxinas CY e PSPs, foram realizadas investigações em alguns corpos dágua do Estado de São Paulo. Das investigações realizadas, a neosaxitoxina foi identificada pela primeira vez no Reservatório Billings e os congêneres, saxitoxina, goniautoxina 2, goniautoxina 3, foram identificados de forma inédita em amostras de água deste reservatório. Com relação à CY, foi desenvolvido um método analítico, parcialmente validado. Entretanto, esta cianotoxina não foi localizada nas amostras de água ou cianobactérias das águas superficiais dos corpos dágua estudados. Este estudo mostra a importância do monitoramento da qualidade das águas dos mananciais quanto à presença de cianotoxinas, especialmente daqueles corpos dágua com a finalidade do consumo humano. / Cities growth usually occur in an unorganized manner. This tendence can generate a variety of sanitary problems, including the degradation of natural resources, such as water bodies. As a consequence, domestic and industrial efluents cause eutrofication of water reservoir, increasing the natural level of phytoplancton, what may form algal bloom. Among the phytoplanktonic organisms that grow in this modified environment it is found the cyanobacteria. Some of them can produce different types of cyanotoxins such as microcystin, anatoxin, cylindrospermopsin (CY) and saxitoxin (PSPs). The probability of production of these cyanotoxins increase according to frequent occurrence of algal blooms episodes. Consequently, water bodies monitoring becomes important to assure water quality. The aim of this project was to develop a specific method to identify the presence of cyanotoxins CY and to investigate PSPs in water bodies in São Paulo State. The results confirmed the presence of neosaxitoxin (NEO), a toxin of PSPs family. It was the first time that Neo was indentified in Billings Reservoir along with other PSPs types: saxitoxin, gonyautoxin 2, gonyautoxin 3. Although the study also included CY monitoring, CY was not identified in the tested samples. The present study confirmed the importance of continuous searching and monitoring of water bodies to grant quality to water used for human consumption.
13

Investigação da cilidrospermopsina e PSPs em amostras de águas superficiais no Estado de São Paulo (OU) Investigação da presença de cilindrospermopsina e saxitoxinas em amostras de águas superficiais no Estado de São Paulo / Cylindrospermopsin and Saxitoxins in superficial water samples Investigation in São Paulo State

Meron Petro Zajac 09 November 2006 (has links)
O crescimento desordenado das cidades tem trazido à tona problemas de saneamento e degradação dos recursos naturais, entre eles a água. O despejo de efluentes domésticos e industriais têm ocasionado a eutrofização dos mananciais, culminando com a proliferação dos fitoplânctons. Esta proliferação tem chegado ao ponto, em certos momentos, de acarretar episódios de floração de algas. Entre os organismos fitoplanctônicos que se desenvolvem no ambiente, estão as cianobactérias, com vários gêneros capazes de produzir diversas cianotoxinas, tais como as microcistinas, anatoxinas, cilindrospermopsinas (CY), saxitoxinas (PSPs), entre outras. Com o aumento da freqüência dos episódios de floração de algas, a probabilidade da ocorrência destas toxinas também aumenta. Como conseqüência disto e devido às exigências legais, os corpos dágua devem ser monitorados para garantir a qualidade da água para consumo humano. Com vistas ao monitoramento da presença das cianotoxinas CY e PSPs, foram realizadas investigações em alguns corpos dágua do Estado de São Paulo. Das investigações realizadas, a neosaxitoxina foi identificada pela primeira vez no Reservatório Billings e os congêneres, saxitoxina, goniautoxina 2, goniautoxina 3, foram identificados de forma inédita em amostras de água deste reservatório. Com relação à CY, foi desenvolvido um método analítico, parcialmente validado. Entretanto, esta cianotoxina não foi localizada nas amostras de água ou cianobactérias das águas superficiais dos corpos dágua estudados. Este estudo mostra a importância do monitoramento da qualidade das águas dos mananciais quanto à presença de cianotoxinas, especialmente daqueles corpos dágua com a finalidade do consumo humano. / Cities growth usually occur in an unorganized manner. This tendence can generate a variety of sanitary problems, including the degradation of natural resources, such as water bodies. As a consequence, domestic and industrial efluents cause eutrofication of water reservoir, increasing the natural level of phytoplancton, what may form algal bloom. Among the phytoplanktonic organisms that grow in this modified environment it is found the cyanobacteria. Some of them can produce different types of cyanotoxins such as microcystin, anatoxin, cylindrospermopsin (CY) and saxitoxin (PSPs). The probability of production of these cyanotoxins increase according to frequent occurrence of algal blooms episodes. Consequently, water bodies monitoring becomes important to assure water quality. The aim of this project was to develop a specific method to identify the presence of cyanotoxins CY and to investigate PSPs in water bodies in São Paulo State. The results confirmed the presence of neosaxitoxin (NEO), a toxin of PSPs family. It was the first time that Neo was indentified in Billings Reservoir along with other PSPs types: saxitoxin, gonyautoxin 2, gonyautoxin 3. Although the study also included CY monitoring, CY was not identified in the tested samples. The present study confirmed the importance of continuous searching and monitoring of water bodies to grant quality to water used for human consumption.
14

Análisis, función y aplicaciones biotecnológicas de las proteínas del plasma seminal de porcino PSP-I y PSP-II

García Hernández, Eva María 04 December 2007 (has links)
La aplicación de procesos biotecnológicos como la separación de espermatozoides X e Y mediante citometría de flujo, pueden generar la eliminación de determinados componentes del plasma seminal necesarios para conservar su funcionalidad. En este sentido, se ha observado que la adición de plasma seminal al medio espermático, protege a los espermatozoides cuando estos son sometidos a separación espermática mediante citometría de flujo. Sin embargo, diversos estudios demuestran que rel efecto beneficioso que ejerce el plasma seminal sobre los espermatozoides reside en determinadas proteínas. En el caso de la especie porcina, hay estudios previos que determinan que el efecto protector que ejerce el plasma seminal sobre los espermatozoides, se debe a una proteína denominada heterodímero PSP-I/PSP-II. El efecto beneficioso de dicha proteína sobre la funcionalidad espermática en espermatozoides de verraco altamente diluidos parece estar conservada, en su subunidad PSP-II y, concretamente, en la fracción peptídica de ésta. Estudiar, además, su localización a lo largo del tracto genital del verraco así como en las distintas fracciones del eyaculado, puede ser importante para llegar a conocer si la presencia de este heterodímero en el medio de recogida espermático de espermatozoides X e Y, es beneficioso tanto en la funcionalidad como en la capacidad fecundante de estos espermatozoides. / Biotechnological procedures of semen, such as sexing using flow cytometry/cell sorting procedures, causes high dilutions during sperm manipulation, linked with the wash away or high dilution of seminal plasma components. Thus, to develop strategies to extend the viability of treated spermatozoa are necessary. It is well known that add seminal plasma (SP) to the sperm media contributes to preserving the integrity and the fertilizing potential of sperm. Nevertheless, the beneficial effects of seminal plasma seem to be restricted to specific proteins of the SP. In porcine, previous studies have related this protective effect of the seminal plasma on the sperm cells to a protein called PSP-I/PSP-II heterodimer. The beneficial effect of this protein on the functionality of highly diluted boar spermatozoa is largely preserved in its PSP-II subunit and does not appear to require its glycan moiety. Moreover, study its localization along male reproductive tract and in different portions of the ejaculate could be important to know if the presence of PSP-I/PSP-II heterodimer in the collection medium for sex sorted spermatozoa is beneficial on the in vitro function and in vivo fertilizing ability.
15

Estudio del plasma seminal y la espermadhesina PSP-I/PSP-II sobre la funcionalidad de los espermatozoides de verraco

Caballero Posadas, Ignacio 22 February 2007 (has links)
En la siguiente tesis se obtuvieron los siguientes resultados. La adición de plasma seminal a los espermatozoides altamente diluidos ejerce un efecto beneficioso variable dependiendo de la fuente de plasma seminal. El heterodímero PSP-I/PSP-II ejerce un efecto beneficioso sobre los espermatozoides altamente diluidos mediante su adhesión al acrosoma. La incubación produce la migración del heterodímero a la región post-acrosomal, siendo eliminado de la superficie espermática. La adición del heterodímero a los medios de cocultivo entre gametos disminuye significativamente la capacidad fecundante de los espermatozoides. La preincubación de los espermatozoides de verraco tanto frescos como congelados preserva la viabilidad y motilidad espermáticas no afecta a la capacidad fecundante de los espermatozoides frescos de verraco y disminuye la capacidad fecundante de los espermatozoides congelados, la cual puede ser restaurada parcialmente mediante un lavado a través de un gradiente de Percoll. / The addition of 10% of seminal plasma from certain boars maintains or enhances the viability of largely extended boar spermatozoa in vitro. The protective effect of the PSP-I/PSP-II heterodimer on highly-extended boar spermatozoa could be related to the adhesion of the heterodimer to the acrosome. Exposures of the gametes to the heterodimer during in vitro gamete co-incubation significantly decrease the sperm penetration rates and number of spermatozoa per oocytes in denuded oocytes. The effect could be mediated by exposed ZP receptors. Exposure of fresh or frozen-thawed boar spermatozoa to PSP-I/PSP-II preserves sperm viability and motility. Although there is no obvious influence of the heterodimer on the capability of fresh diluted boar spermatozoa to penetrate homologous oocytes, PSP-I/II exerts a deleterious effect when frozen-thawed spermatozoa are used to penetrate IVM-oocytes. A subsequent washing through a Percoll gradient estored sperm function in some of the cells.
16

Oxygen-Sensitive Luminophores: A Survey of the Literature and Efforts toward a Novel Porphyrin-Pillared Zirconium Phosphonate

Wright, Joseph 01 January 2016 (has links)
Measurement and mapping of the pressure distribution across the surface of a suitably scaled model is an integral step in the design of any aircraft or automobile. For this purpose, the traditional workhorses of the aeronautic and automotive industries have been pressure taps--small orifices that contain electronic pressure transducers. Unfortunately, in addition to the limited spatial resolution achievable with such devices, their technical complexity and cost constitute serious disadvantages. For more than 35 years, researchers have pursued a fundamentally different alternative: indirect measurement of pressure via oxygen-induced quenching of the luminescence emitted by certain chemical species. Porphyrin complexes of dipositive palladium and especially platinum have emerged as one of the principal classes of oxygen-sensitive luminophores; ruthenium(II) polypyridyl complexes comprise another. Various other metals also form luminescent coordination complexes that are susceptible to quenching by O2, however, and these too have contributed to the diversity of luminophores that are now available for incorporation into pressure-sensitive paints and related films and coatings. After treating the photophysics of luminescence quenching by molecular oxygen and quantitative descriptions of this phenomenon in the ideal case and in heterogeneous media, the thesis presents a comprehensive survey of the chemical literature on oxygen-sensitive luminophores. Efforts to prepare and characterize a novel porphyrin-pillared mixed zirconium phosphonate are then detailed. Following complexation of Pt(II) ions by the porphyrin moieties, this material is expected to display oxygen-sensitive luminescence and should ameliorate such difficulties as luminophore aggregation and matrix photodegradation that are associated with many existing pressure-responsive coatings. Its preparation necessitated preliminary formation of a porphyrin functionalized with two phenylphosphonic acid groups, which was obtained by synthesizing dipyrromethane and diethyl 4-formylphenylphosphonate and condensing these two precursors. The mixed phosphonate, a layered material assembled from ZrOCl2 · 8H2O, methylphosphonic acid, and the aforementioned porphyrin, was then prepared in refluxing HF. Solid-state 31P NMR spectra and powder X-ray diffraction patterns were acquired for the final product, its estimated interlayer spacing of 22.8 Å figuring prominently in analysis and discussion of the X-ray data.
17

Parameter Estimation and Tracking in Physical Layer Network Coding

Jain, Manish 2011 May 1900 (has links)
Recently, there has been a growing interest in improving the performance of the wireless relay networks through the use of Physical Layer Network Coding (PLNC) techniques. The physical layer network coding technique allows two terminals to transmit simultaneously to a relay node and decode the modulo-2 sum of the transmitted bits at the relay. This technique considerably improves performance over Digital Network Coding technique. In this thesis, we will present an algorithm for joint decoding of the modulo-2 sum of bits transmitted from two unsynchronized transmitters at the relay. We shall also address the problems that arise when boundaries of the signals do not align with each other and when the channel parameters are slowly varying and are unknown to the receiver at the relay node. Our approach will first jointly estimate the timing o sets and fading gains of both signals using a known pilot sequence sent by both transmitters in the beginning of the packet and then perform Maximum Likelihood detection of data using a state-based Viterbi decoding scheme that takes into account the timing o sets between the interfering signals. We shall present an algorithm for simultaneously tracking the amplitude and phase of slowly varying wireless channel that will work in conjunction our Maximum Likelihood detection algorithm. Finally, we shall provide extension of our receiver to support antenna diversity. Our results show that the proposed detection algorithm works reasonably well, even with the assumption of timing misalignment. We also demonstrate that the performance of the algorithm is not degraded by amplitude and/or phase mismatch between the users. We further show that the performance of the channel tracking algorithm is close to the ideal case i.e. when the channel estimates are perfectly known. Finally, we demonstrate the performance boost provided by the receiver antenna diversity.
18

高クヌッセン数流れでの圧力計測に適した感圧分子膜の開発

松田, 佑, MATSUDA, Yu, 森, 英男, MORI, Hideo, 新美, 智秀, NIIMI, Tomohide, 上西, 裕之, UENISHI, Hiroyuki, 平光, 円, HIRAKO, Madoka 06 1900 (has links)
No description available.
19

Implementering av ett kortbetalningssystem

Bjelkstål, Per Anders January 2008 (has links)
<p>I ett kortbetalningssystem såsom Visa International Service Association (Visa) finns det fem stycken tongivande parter: kortinlösaren; kortutgivaren; kortinnehavaren; säljföretaget och Payment Service Provider (PSP). Ett säljföretag som låter sina kunder betala för varor och tjänster på sin webbplats skickar kundernas kortnummer krypterat till en PSP som vidarebefodrar dessa till VisaNet som är dataknutpunkten i Visa. VisaNet söker med hjälp utav kortnumret upp den bank som har utgivit kortet och efterfrågar samma bank om en transaktion får ske från kortet. VisaNet får ett svar som vidarebefordras vidare tillbaka till säljföretaget som sedermera även får sina pengar överförda till sitt konto från kundens konto.</p><p>Uppdragsgivaren till detta examensarbete skall utveckla ett helt eget system och bli sin egen PSP utifall uppdragsgivaren beräknar att mer än 1,3 miljoner stycken kortbetalningar kommer att ske genom uppdragsgivarens kortbetalningssystem per år. När detta examensarbete utfördes uppskattades antalet kortbetalningar per år inte till denna siffra och rapportförfattaren utvecklade därför ett korbetalningssystem med hjälp utav en befintlig PSP.</p><p>Kortbetalningssystemets kärna är ett API som andra systemutvecklare hos uppdragsgivaren kan anropa. API:t har ett antal funktioner såsom att utföra en kortbetalning, reservera en kortbetalning eller att avbryta en reserverad kortbetalning. Rapportförfattaren har även utvecklat ett grafiskt övervaknings- och administrationsgränssnitt för att kunna övervaka de kortbetalningar som sker samt enkelt kunna felsöka fel som uppstår i systemet.</p>
20

Kardiovaskulinės reabilitacijos pacientų informacinės sistemos kūrimas ir tyrimas / Cardiovascular reabilitation patients infromation system development and analysis

Banelis, Andrius 25 May 2005 (has links)
Project dedicated for the united information base creation and storage of the cardiovascular reabilitation patients. Using this reabilitation it is necessary to watch the test results of the patient, analyse and systematize them. Besides collected information can be used for the later treatment of the patient. Thus having a huge storage it is hard to find record if it is on paper, in that case invoking information technology, which will ease storage of the big information quantity, quick it processing and analysis. Besides selection of that organization bussines reorganization will sharply increase workers work efficiency. Nowadays test equipment deliver results which a specialist have to transform into understandable form that these results could be used for analysis about patient health status.

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