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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.
111

Comportamento de prog?nies de pinh?o-manso (Jatropha curcas L.) em casa de vegeta??o e no campo quanto ? vari?veis morfoagron?micas / Behaviour progenies of physic-nut (Jatropha curcas L.) in a green house and field regarding morphoagronomic variables

RIBEIRO, Nath?lia Virg?nia da Silva 24 July 2013 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-09-25T18:06:32Z No. of bitstreams: 1 2013 - Nath?lia Virg?nia da Silva Ribeiro.pdf: 1961349 bytes, checksum: 43e989102153b88ad17a4eefb1e37f9e (MD5) / Made available in DSpace on 2018-09-25T18:06:32Z (GMT). No. of bitstreams: 1 2013 - Nath?lia Virg?nia da Silva Ribeiro.pdf: 1961349 bytes, checksum: 43e989102153b88ad17a4eefb1e37f9e (MD5) Previous issue date: 2013-07-24 / CAPES / The species Jatropha curcas, popularly known as physic nut, belonging to the family Euphorbiaceae, is currently regarded as one of the greatest potential of oil seeds for biodiesel production in the world. However, the knowledge of available genetic variability and productive behavior of the species are still scarce. This work is part of the Breeding Program of Jatropha curcas developed in UFRRJ, and its objective was know some morphological and productive aspects of 10 progenies of physic nut (Jatropha curcas), grown in greenhouse and camp up to 17 months old, selected from female parents belonging to the Germplasm Collection of physic nut (Jatropha curcas) of the Department of Plant Science at the Institute of Agronomy of UFRRJ. It is expected this study provide important information for the continued Breeding Program of the species in UFRRJ. The experiment was installed in October 2011 in greenhouse, and consisted of 10 progenies of physic nut arranged in experimental design randomized blocks with 3 repetitions, and 15 plants by experimental parcel. After 4 evaluation in greenhouse, the plants were transferred to the camp, here were done 6 evaluation, the last being in April 2013. In the greenhouse it was evaluated aspects related to the germination of the progeny and the behavior of young plants. In the first case, it was estimated germination itself progenies and the index of germination speed (IGS), and at the second, the size of the petiole (SMP), number, width and length of fully developed leaves, respectively, discriminated as NDL, WDL and LDL, insertion angle of the leaf (IALs), length relationship and width of leaf (LWL), height of young plants (HYP), stem diameter (SDI) and branches number (BNU). The obtained data were submitted to analysis of variance, mean test via DMS-t and correlation analysis. The coefficient of genotypic determination (H2), of genotypic variation (CVg) and experimental variation (CVe) were also estimated, and variation index (VIg). The mean germination percentage for Jatropha curcas species was 68,23%, and the mean index germination speed was of 8,60 seeds germinated per day. The progeny that reached higher percentage of gemination and higher germination speed were UFRRJ/PM05 (83,33 and 3,12) and UFRRJ/PM01 (83,33 and 3,38). Whereas the progenies UFRRJ/PM10 and UFRRJ/PM04 were the ones with the lowest percentage of germination and germinated more slowly. In the greenhouse was no statistically significant difference between treatments for the variables SMP, NDL, SDI, HYP, BNU, LDL, WDL. Only for LWL and IALs not statistical difference was detected signficativa. In the camp, it was evaluated variables related to morphological and productive. The morphological variables were: insertion angle of the leaf (IALs), height of young plants (HYP), stem diameter (SDI), of branches number (BNU) and the size of the petiole (SMP). Variables related to aspects of production were: fruit number (FNU), average fruit weight (AFW), fruit length (FRL), fruit width (FRW), weight of fruit of the crop (WFC), weight of dries seeds (WDS), seeds number per fruit (SNF=SNU/FNU), seeds number (SNU), seed length (SEL), seed width (SEW), average seed weight (ASW=GPR/SNU) and grain production (GPR= SNUxASW). All data obtained for each stage of treatment in this study were submitted to analysis of variance, mean test way DMS-t and correlation analyzes. Only for the variables related to morphological aspects considered the effect of season in the ANOVA. Were also estimated the coefficient of genotypic determination (H2), genotypic variation (CVg) and experimental variation (CVe), and the variation index (IVg). All variables (morphological and production) were subjected to regression analysis over the 6 collection periods. Was also estimated genetic the following parameters: genetic variance (?2g), additive variance (?2a), heritability of family means, within family, stratified mass and mass in the experiment. The estimation of genetic parameters was based on the last review performed in the experiment, not considering, therefore, the season effect. From previously mentioned analysis it was observed that all the variables related to morphological aspects showed statistically significant differences between treatments. As for variables related to production only FRW, AFW, SEL and ASW no statistically significant difference. Characters related to leaf morphology showed low coefficients of determination and variation index, while the latter parameters were higher for the variables HYP (83,24 e 0,64) e BNU (80,92 e 0,59), respectively, evaluated in plants in a greenhouse. Progenies with the highest mean branches number were UFRRJ/PM07 (0,49) and UFRRJ/PM08 (0,47). In the camp, the BNU variable had the highest coefficient of genotypic determination (84,16) and variation index (0,54) again. Variables SDI, HYP, IALs and BNU showed a linear behavior over the following months, only exception to IALs variable studied in the progeny UFRRJ/PM 10. Variable SMP proved oscillating in all progenies during the months evaluated. Regarding the variables related to production, the progeny had a different behavior between them. Therefore, the selection of these variables are not indicated when you want to increase grain production in physic nut. Only when considering the quantitative variables is that selection for increased production becomes more effective, for example, the selection of the seeds number. The variable branches number (BNU) was positively correlated with almost all variables in the greenhouse and all related to the production characteristics analyzed in the camp, therefore, this variable can be used in precocious selection for increased production in physic nut. The progenies UFRRJ/PM08 and UFRRJ/PM01 were the most promising in respect of seed production, but, evaluation over the years are still needed, as the plants of the experiment were evaluated in still too early to age, and then, physiological and experimental aspects may be being even more important than genetic factors. / A esp?cie Jatropha curcas, popularmente conhecida como pinh?o manso, pertencente ? fam?lia Euphorbiaceae, ? considerada atualmente como uma das oleaginosas de maior potencial para a produ??o de biodiesel no mundo. No entanto, o conhecimento da variabilidade gen?tica dispon?vel e o comportamento produtivo da esp?cie ainda s?o escassos. O presente trabalho ? parte do Programa de Melhoramento Gen?tico de Jatropha curcas desenvolvido na UFRRJ, e teve como objetivo conhecer alguns aspectos morfol?gicos e produtivos de 10 prog?nies de pinh?o-manso (Jatropha curcas), cultivadas em casa de vegeta??o e campo at? aos 17 meses de idade, selecionadas a partir de genitores femininos pertencentes ? Cole??o de Germoplasma de pinh?o-manso (Jatropha curcas) do Departamento de Fitotecnia do Instituto de Agronomia da UFRRJ. Espera-se com este trabalho fornecer informa??es importantes para a continuidade do Programa de Melhoramento da esp?cie na UFRRJ. O experimento foi instalado em outubro de 2011 em casa de vegeta??o, e foi composto por 10 prog?nies de pinh?o-manso dispostas em delineamento em blocos ao acaso com 3 repeti??es, e 15 plantas por parcela experimental. Ap?s 4 avalia??es em casa de vegeta??o, as plantas foram transferidas para o campo, onde foram realizadas 6 avalia??es, sendo a ultima no m?s de abril de 2013. Em casa de vegeta??o avaliou-se aspectos relacionados ? germina??o das prog?nies e o comportamento das plantas jovens. No primeiro caso, estimou-se a germina??o propriamente dito das prog?nies e o ?ndice de velocidade de germina??o (IVG), e no segundo, o tamanho do pec?olo (TMP), n?mero, largura e comprimento de folhas completamente desenvolvidas, respectivamente, discriminados como NFD, LAF e COF, ?ngulo de inser??o da folha (AIFc), rela??o comprimento e largura de folha (CLF), altura de plantas (APJ), di?metro de caule (DIC) e n?mero de ramos (NDR). Os dados obtidos foram submetidos a an?lises de vari?ncia, teste de m?dia via DMS-t e an?lise de correla??o. Tamb?m foram estimados os coeficientes de determina??o genot?pico (H2), de varia??o genot?pico (CVg) e de varia??o experimental (CVe), e o ?ndice de varia??o (IVg). A porcentagem m?dia de germina??o para a esp?cie Jatropha curcas foi de 68,23%, e o ?ndice m?dio de velocidade de germina??o foi de 8,60 sementes germinadas por dia. As prog?nies que atingiram maiores percentuais de gemina??o e maior velocidade de germina??o foram a UFRRJ/PM05 (83,33 e 3,12) e UFRRJ/PM01 (83,33 e 3,38). Enquanto que as prog?nies UFRRJ/PM10 e UFRRJ/PM04 foram as que apresentaram os percentuais de germina??o mais baixos e germinaram mais lentamente. Em casa de vegeta??o houve diferen?a estat?stica significativa entre os tratamentos para as vari?veis TMP, NFD, DIC, APJ, NDR, COF, LAF. Apenas para CLF e AIFc n?o se detectou diferen?a estat?stica signficativa. No campo, avaliou-se vari?veis ligadas aos aspectos morfol?gicos e produtivos. As vari?veis morfol?gicas analisadas foram: ?ngulo de inser??o da folha (AIFc), altura de plantas (APJ), di?metro de caule (DIC), n?mero de ramos (NDR), tamanho m?dio de entren? (MECc). As vari?veis relacionadas aos aspectos de produ??o foram: n?mero de frutos (NFR), peso m?dio do fruto (PFR), comprimento do fruto (CFR), largura do fruto (LFR), peso de frutos da colheita (PFC), peso de sementes secas (PMSs), n?mero de sementes por fruto (NSF = NSE/NFR), n?mero de sementes (NSE), comprimento da semente (CMS), largura da semente (LSE), peso m?dio de sementes (PMS=PSP/NSE) e produ??o de gr?os (PGP=NSExPMS). Todos os dados obtidos para cada tratamento nesta etapa do trabalho foram submetidos ?s an?lises de vari?ncia, teste de m?dia via DMS-t e an?lises de correla??o. Apenas para as vari?veis ligadas aos aspectos morfol?gicos considerou-se o efeito de ?poca na anova. Foram estimados tamb?m os coeficientes de determina??o genot?pico (H2), de varia??o genot?pico (CVg) e de varia??o experimental (CVe), e o ?ndice de varia??o (IVg). Todas as vari?veis (morfol?gicas e de produ??o) foram submetidas a an?lises de regress?o ao longo das 6 ?pocas de coleta. Estimou-se tamb?m os seguintes par?metros gen?ticos: vari?ncia gen?tica (?2g), vari?ncia aditiva (?2a), herdabilidades entre m?dias de fam?lias, dentro de fam?lia, massal estratificada e massal no experimento. A estimativa dos par?metros gen?ticos foi com base na ?ltima avalia??o realizada no experimento, n?o considerando, portanto, o efeito de ?poca. A partir das an?lises anteriormente citadas observou-se que todas as vari?veis ligadas aos aspectos morfol?gicos apresentaram diferen?a estat?stica significativa entre os tratamentos. Quanto as vari?veis relacionadas ? produ??o apenas LFR, PFR, CMS, e PMS n?o apresentaram diferen?a estat?stica significativa. Caracteres relacionados ? morfologia da folha apresentaram baixos coeficientes de determina??o e ?ndice de varia??o, enquanto que estes mesmos par?metros foram altos para as vari?veis APJ (83,24 e 0,64) e NDR (80,92 e 0,59), respectivamente, avaliados em plantas em casa de vegeta??o. As prog?nies que apresentaram as maiores m?dias do n?mero de ramos foram as UFRRJ/PM07 (0,49) e UFRRJ/PM08 (0,47). No campo, a vari?vel NDR apresentou novamente o maior coeficiente de determina??o genot?pico (84,16) e ?ndice de varia??o (0,54). As vari?veis DIC, APJ, AIFc e NDR apresentaram um comportamento linear ao passar dos meses, exce??o apenas para a vari?vel AIFc estudada na prog?nie UFRRJ/PM 10. A vari?vel MECc mostrou-se oscilante em todas as prog?nies durante os meses avaliados. Em rela??o ?s vari?veis ligadas ? produ??o, as prog?nies tiveram um comportamento diferenciado entre si. Todas as vari?veis ligadas aos aspectos morfol?gicos da semente (largura, comprimento e peso m?dio) apresentaram baix?ssima ou nenhuma variabilidade gen?tica entre as prog?nies estudadas. Portanto, a sele??o sobre estas vari?veis n?o s?o indicadas quando se deseja o aumento da produ??o de gr?os em pinh?o-manso. Apenas quando se considera vari?veis de natureza quantitativa ? que a sele??o para o aumento de produ??o torna-se mais efetiva, como por exemplo, a sele??o sobre o n?mero de sementes. A vari?vel n?mero de ramos (NDR) se correlacionou positivamente com quase todas as vari?veis analisadas em casa de vegeta??o e com todos os caracteres relacionados ? produ??o analisados no campo, assim sendo, essa vari?vel pode ser utilizada em sele??o precoce visando o aumento da produ??o em pinh?o-manso. As prog?nies UFRRJ/PM08 e UFRRJ/PM01 foram as mais promissoras no que se refere a produ??o de sementes, por?m, avalia??es ao longo dos anos ainda s?o necess?rias, visto que as plantas do experimento foram avaliadas em idade ainda muito precoce, e portanto, aspectos fisiol?gicos e experimentais podem estar sendo at? mais importantes do que aspectos gen?ticos.
112

Simulação do escoamento da produção de milho, soja e trigo dos núcleos regionais de Cascavel e Toledo / A computational model for simulating the transport of corn, soybean and wheat yield from west parana state region.

Sandri, Maria Felomena Alves de Oliveira 18 July 2006 (has links)
Made available in DSpace on 2017-05-12T14:48:30Z (GMT). No. of bitstreams: 1 Maria Felomena de Oliveira Sandri.pdf: 527012 bytes, checksum: e6611509a5628405238b9e31b3319b77 (MD5) Previous issue date: 2006-07-18 / In the West of Paraná State, the Regional Nuclei of Agricultural State Secretary SEAB - are located in Cascavel and Toledo. The first one has an area of 1,283,062.58 ha, which includes 28 cities; the second one is 849,732.80 ha wide and counts with 20 cities. These Regional Nuclei are responsible for twenty percent of the Whole Production Value, requiring agribusiness state production, as well as important areas concerning/ corn, soybean at wheat production; and they reach almost 4.8 millions tones/grains per year. In order to spread out this production, railways and roadways are employed, even though it decisionmaking affects traffic conditions and implies in costs. Researches Operations tools can be applied, which aims are evaluation, management and planning to improve transportation system use Among these tools, it can be mentioned the simulation practice, which, by means of computational models, helps on choosing how the experiment will be carried out, such as: (i) sensitivity analyses; (ii) scenario analyses, (iii) optimization; and (iv) Monte Carlo Simulation. Considering these potentialities, this trial was carried out aiming at implementing a computational model to simulate grains and oilseeds transportation from the Regional Nuclei of Cascavel and Toledo, respectively. This simulation concerned about 2003, 2004 and 2005 years; and sensitivity analysis was also conducted considering changes of percentage indexes related to the loads destination to roadways and railways, respectively. The applied model showed a great potential for supporting management of grains and oilseeds transportation system, with diversity of reports and information. For example, in 2004, at Cascavel Regional Nucleus, 2,2 millions tonnes of products were processed, with a consumption of 44.916,74 m-3 of firewood, and 34.489 transportations were also made from Cascavel to Paranaguá Port using the roadway / Os Núcleos Regionais de Cascavel e Toledo da Secretaria de Estado da Agricultura e Abastecimento SEAB do Paraná estão localizados na região Oeste. O primeiro núcleo abrange uma área agrícola de 1.283.062,58 ha e compreende 28 munícipios, enquanto o segundo tem área agrícola de 849.732,80 ha e conta com 20 municípios. Esses dois núcleos regionais participam com 20% do Valor Bruto da Produção, os quais correspondem aos valores produzidos pelo agronegócio no Estado e são importantes polos na produção de milho, soja e trigo, cujo total é de, aproximadamente, 4,8 milhões de toneladas. Para o escoamento dessa produção, são utilizados os modais rodoviários e ferroviário, fato que afeta as condições de trafégo e implica em custos. Para o aprimoramento do uso de um sistema de transporte, podem ser utilizados ferramentais de Pesquisa Operacional, os quais prestam avaliações, gestão e planejamento. Dentre os ferramentais, pode ser destacada a simulação que, por meio de modelos computacionais, propicia o auxílio à tomada de decisão pela condução de experimentos tais como: (i) análise de sensibilidade; (ii) comparação de cenários; (iii) otimização e (iv) simulação de Monte Carlo. Considerando essa potencialidade, este trabalho foi conduzido com o objetivo de implementar um modelo computacional para simular a movimentação de cargas de grãos e oleaginosas a partir dos Núcleos Regionais de Cascavel e Toledo. Essas simulações referem-se aos anos de 2003, 2004 e 2005 e conduzida análise de sensibilidade ao considerar a alteração dos índices de destinação de cargas para os modais rodoviário e ferroviário, respectivamente. O modelo empregado apresenta potencialidade de aplicação em procedimentos para gestão do sistema de transporte de grãos e oleaginosas, cujos destaques são a diversidade de relatórios gerados e as informações disponibilizadas. Logo, pode-se ter o exemplo de uma informação, no ano de 2004, para o Núcleo Regional de Cascavel, em que foram processadas 2,2 milhões de toneladas de produto; consumidos 44.916,74 m-3 de lenha, e feita a movimentação de 34.489 cargas pelo eixo Cascavel Porto de Paranaguá por meio de modal rodoviário
113

Ismailova, Rita 01 September 2012 (has links) (PDF)
The subject of this thesis is the study of cryptographic hash functions, which utilize block ciphers as underlying chain functions. It is mainly concerned with the analysis of the three hash algorithms, the Whirlpool, Gr&oslash / stl and Grindahl. All these hash functions have underlying block ciphers that are modified versions of the Advance Encryption Standard and we investigate the behavior of these block ciphers under the integral attack. Statistical tests, such as the avalanche test and the collision test, are the regular tools for examining the hash function security. In this work, we inspect the statistical behavior the three hash functions and search for collisions. Although it is very difficult to obtain collisions for the actual algorithms, we find some collisions under slight modifications of the original constructions. The ease or difficulty of finding a collision for a modified version also shows the respective importance of the specific hash function branch, missing in the modified version.
114

Depositional Stacking Patterns And Cycles Of Garzan Formation In The Garzan-germik Oil Filed: An Approach To Cycle To Log Correlation

Yildizel, Zeynep Elif Gaziulusoy 01 June 2008 (has links) (PDF)
The Garzan Formation is a deepening upward marine carbonate including successions ranging from subtidal to open marine facies deposited in the Maastrichtian. The Garzan Formation is composed of five microfacies types / Miliolid Wackestone (subtidal), Orbitoid Miliolid Wackestone, Rudist Wackestone (backshoal to shoal), Rotalid Miliolid Wackestone (shoal to foreshoal) and Pelagic Foraminiferal Mudstone (foreshoal to open marine). These five microfacies are stacked in different combinations consisting of five types of depositional cycles. The type A and D cycles the building blocks of transgressive systems tract (retrogradational), whereas type B and C cycles are deposited during highstand systems tract (aggradational). The type E cycle is progradational and also corresponds to the highstand systems tract deposits. The maximum flooding surface is usually located within the type D cycle towards the top of the formation. vi Generally, the base of the Garzan Formation deposition starts with highstand systems tract deposits (type E and C cycles) and overlain by transgressive systems tract deposits (type A cycle) in between there is a type 2 sequence boundary. Then deposition continues with highstand systems tract deposits (alternation of type B and C cycles) which are aggradational in character. The top of the Formation is characterized by transgressive systems tract deposits (type D cycle) which usually includes the maximum flooding surface. The second type 2 sequence boundary is located below the type D cycle. There are four of the stacking patterns observed in the Garzan Formation. The GR values change from relatively high to low API in type D and A cycles, whereas a relative shift from low to high API is observed in type E cycle. The GR in the type B and C cycles does not display any relative change. There is no net movement in the SONIC readings in type A, B, C and E cycles / however there is a relative shifting from low velocity to high velocity in type D cycle. In Garzan deposition opposing the general patterns, a decrease in GR readings indicates a decrease in energy and relatively deepening. In carbonate depositional systems predicting the depositional environment from the logs should only be accomplished with microfacies control, otherwise the interpretation will be erroneous.
115

Alpha-beta Transition In Quartz

Lider, Mustafa Cem 01 September 2011 (has links) (PDF)
Alpha-Beta transition in quartz is studied using the Raman scattering. The Raman frequencies of some lattice modes are analyzed at various temperatures close to the alpha beta transition in quartz. For this analysis, the experimental data from the literature is used and the soft mode behavior of those Raman phonons is investigated . On the basis of the predictions of some models, the temperature dependencies for the Raman frequencies of the lattice modes which move towards zero (soft mode) and their bandwidths close to the transition temperature Tc are explained for the alpha-beta transition in quartz. In addition, by using the experimental volume data from literature, calculation of the temperature dependence of the Raman frequencies through the Gr&uuml / neisen parameter have been studied near the phase transition.
116

The Human Y chromosome and its role in the developing male nervous system

Johansson, Martin M. January 2015 (has links)
Recent research demonstrated that besides a role in sex determination and male fertility, the Y chromosome is involved in additional functions including prostate cancer, sex-specific effects on the brain and behaviour, graft-versus-host disease, nociception, aggression and autoimmune diseases. The results presented in this thesis include an analysis of sex-biased genes encoded on the X and Y chromosomes of rodents. Expression data from six different somatic tissues was analyzed and we found that the X chromosome is enriched in female biased genes and depleted of male biased ones. The second study described copy number variation (CNV) patterns in a world-wide collection of human Y chromosome samples. Contrary to expectations, duplications and not deletions were the most frequent variations. We also discovered novel CNV patterns of which some were significantly overrepresented in specific haplogroups. A substantial part of the thesis focuses on analysis of spatial expression of two Y-encoded brain-specific genes, namely PCDH11Y and NLGN4Y. The perhaps most surprising discovery was the observation that X and Y transcripts of both gene pairs are mostly expressed in different cells in human spinal cord and medulla oblongata. Also, we detected spatial expression differences for the PCDH11X gene in spinal cord. The main focus of the spatial investigations was to uncover genetically coded sexual differences in expression during early development of human central nervous system (CNS). Also, investigations of the expression profiles for 13 X and Y homolog gene pairs in human CNS, adult brain, testes and still-born chimpanzee brain samples were included. Contrary to previous studies, we found only three X-encoded genes from the 13 X/Y homologous gene pairs studied that exhibit female-bias. We also describe six novel non-coding RNAs encoded in the human MSY, some of which are polyadenylated and with conserved expression in chimpanzee brain. The description of dimorphic cellular expression patterns of X- and Y-linked genes should boost the interest in the human specific gene PCDH11Y, and draw attention to other Y-encoded genes expressed in the brain during development. This may help to elucidate the role of the Y chromosome in sex differences during early CNS development in humans. / <p>chinese, finnish, norwegian, schizophrenia, bipolar, bipolar disorder, msy, male specific region Y, PAR1, PAR2, pseudoautosomal, male-biased, female-biased, male biased, female biased, ashkenazi population, structure, variants, YHRD, Elena Jazin, Björn Reinius, Per Ahlberg, brain, hjärna, CNS, central nervous system, IR2, inverted repeat 2, isodicentric, genetics, genetik, padlock, rolling circle, amplification, PCR, sY1191, sY1291, STS, DDX3Y, DAZ, AZFa, AZFb, AZFc, AZF, Repping, haplogroup J, rearrangements, DE-M145, I-M170, E-M96, Q-M242, R-M207, O-M175, G-M201, D-M174, C-M130, NO-M214, N-M231, poland</p>
117

The effect of general relativistic frame dragging on millisecond pulsar visibility for the H.E.S.S. telescope / C. Venter

Venter, Christo January 2004 (has links)
It has been noted by several authors that General Relativistic frame dragging in rotating neutron stars is a first order effect which has to be included in a self-consistent model of pulsar magnetospheric structure and associated radiation and transport processes. To this end, I undertook the present study with the aim of investigating the effect of General Relativity (GR) on millisecond pulsar (MSP) visibility. I developed a numerical code for simulating a pulsar magnetosphere, incorporating the GR-corrected expressions for the electric potential and field. I included curvature radiation (CR) due to primary electrons accelerated above the stellar surface, as well as inverse Compton scattering (ICS) of thermal X-ray photons by these electrons. I then applied the model to PSR J0437-4715, a prime candidate for testing the GR-Electrodynamic theory, and examined its visibility for the H.E.S.S. telescope. I also considered the question of whether magnetic photon absorption would take place for this particular pulsar. In addition, I developed a classical model for comparison with the GR results. I found that the typical electron energies and associated CR photon energies are functions of position above the polar cap (PC). These energies are also quite smaller in the GR case than in the classical case due to the different functional forms of the GR and classical electric fields. I found the CR energy cut-off to be ~ 4 GeV compared to the well-known classical value of ~ 100 GeV. Since the H.E.S.S. energy threshold is ~ 100 GeV, it seems as though the CR component will not be visible, contrary to wide-held opinion. However, the ICS component seems to be well in excess of the H.E.S.S. energy threshold and is expected to be visible. I also found that no pair production will take place for PSR J0437-4715. Hopefully, forthcoming H.E.S.S. observations will provide validation of these results. KEY WORDS: General relativistic frame dragging, GR electrodynamics, millisecond pulsar visibility, non-thermal radiation processes, pair production, H.E.S.S., individual pulsars: PSR J0437-4715. / Thesis (M.Sc. (Physics))--North-West University, Potchefstroom Campus, 2004.
118

Les prières pour le baptême dans l'Euchologe Barberini grec 336 : analyse théologique et rituelle

Bozinis, Petros 26 September 2013 (has links) (PDF)
L'euchologe Barberini grec 336 de la bibliothèque Vaticane est le témoin le plus ancien et le plus important du rite byzantin. Les prières du baptême que cet euchologe contient constituent un rite complet du baptême, de façon à ce que l'officiant puisse célébrer le rite du baptême. L'ordre et le contenu des prières lues par l'officiant sont en général les mêmes à ceux qui sont actuellement en usage dans les églises de l'orient qui suivent le typique constantinopolitain : i. la prière pour faire un catéchumène, ii. les exorcismes, iii. les prières de renonciation et adhésion, iv. la litanie diaconale, v. la prière faite par le prêtre qui va baptiser, vi. les prières pour la bénédiction de l'eau, vii. les prières pour l'onction pré-baptismale, viii. les prières pour l'immersion baptismale, ix. les prières pour l'onction post-baptismale, x. la prière pour les ablutions, xi. la prière pour la tonsure d'enfant. Dans l'euchologe, il y a aussi une autre prière pour le renoncement - adhésion sous le titre "Renoncement et adhésion, qui se font sous la présidence de l'archevêque à la sainte Préparation de Pâques" qui est très important parce qu'il provient de l'époque de Chrysostome. En ce qui concerne le credo baptismal qui se trouve dans l'euchologe Barberini gr.336, il s'agit du Credo de Nice-Constantinople. En général, les prières pour le baptême de l'euchologe Barberini grec 336 concernent des candidats adultes. Néanmoins, on ne peut pas exclure le baptême des enfants. Dans la prière pour la tonsure des enfants, ceux-ci sont considérés comme déjà baptisés. En ce qui concerne les enfants, l'euchologe contient deux prières qui paraissent symboliser leur inscription dans les ordres des catéchumènes. Les enfants sont considérés en tant que personnes. L'analyse des prières du baptême concernant la personne divine évoquée par le célébrant aide à distinguer les prières qui précèdent les controverses christologiques. Les prières qui s'adressent simplement à Dieu sont considérées comme plus anciennes (avant le Vème siècle) puisque là, ce n'était pas nécessaire que la divinité de la personne du Fils soit discriminée. Dans l'euchologe, il y a aussi des prières qui concernent le retour des hérétiques. On les distingue en trois catégories : a) ceux qui sont acceptés dans l'église en libelles et en onction au saint myron, b) ceux qui sont acceptés en libelles et c) ceux qui sont acceptés en baptême. Le critère qui distinguait ceux qui seraient acceptés en libelle ou en chrismation à ceux qui seraient baptisés dès le début c'était leur baptême précédent en une ou en trois immersions. Par ailleurs, la distinction est liée à l'acceptation ou non du dogme pour la Sainte Trinité de la part des hérétiques. Il est remarquable que en VIIIème siècle l'église montrait une tolérance aux hérétiques qui étaient reçus en libelle et en chrismation, parce qu'elle estimait qu'ils acceptaient le dogme pour la Sainte Trinité mais qu'ils l'interprétaient incorrectement. Enfin, à l'époque du codex Barberini gr.336, le rite du baptême était indissolublement lié à la divine liturgie suivant la tradition antérieure. Les baptisés, juste après l'immersion baptismale et l'onction au myron, devenaient participants du corps et du sang du Christ.
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The effect of general relativistic frame dragging on millisecond pulsar visibility for the H.E.S.S. telescope / C. Venter

Venter, Christo January 2004 (has links)
It has been noted by several authors that General Relativistic frame dragging in rotating neutron stars is a first order effect which has to be included in a self-consistent model of pulsar magnetospheric structure and associated radiation and transport processes. To this end, I undertook the present study with the aim of investigating the effect of General Relativity (GR) on millisecond pulsar (MSP) visibility. I developed a numerical code for simulating a pulsar magnetosphere, incorporating the GR-corrected expressions for the electric potential and field. I included curvature radiation (CR) due to primary electrons accelerated above the stellar surface, as well as inverse Compton scattering (ICS) of thermal X-ray photons by these electrons. I then applied the model to PSR J0437-4715, a prime candidate for testing the GR-Electrodynamic theory, and examined its visibility for the H.E.S.S. telescope. I also considered the question of whether magnetic photon absorption would take place for this particular pulsar. In addition, I developed a classical model for comparison with the GR results. I found that the typical electron energies and associated CR photon energies are functions of position above the polar cap (PC). These energies are also quite smaller in the GR case than in the classical case due to the different functional forms of the GR and classical electric fields. I found the CR energy cut-off to be ~ 4 GeV compared to the well-known classical value of ~ 100 GeV. Since the H.E.S.S. energy threshold is ~ 100 GeV, it seems as though the CR component will not be visible, contrary to wide-held opinion. However, the ICS component seems to be well in excess of the H.E.S.S. energy threshold and is expected to be visible. I also found that no pair production will take place for PSR J0437-4715. Hopefully, forthcoming H.E.S.S. observations will provide validation of these results. KEY WORDS: General relativistic frame dragging, GR electrodynamics, millisecond pulsar visibility, non-thermal radiation processes, pair production, H.E.S.S., individual pulsars: PSR J0437-4715. / Thesis (M.Sc. (Physics))--North-West University, Potchefstroom Campus, 2004.
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Effect Of Salt Stress On Antioxidant Defense Systems Of Sensitive And Resistant Cultivars Of Lentil (lens Culinaris M.)

Cicerali, Isin Nur 01 July 2004 (has links) (PDF)
ABSTRACT EFFECT OF SALT STRESS ON ANTIOXIDANT DEFENSE SYSTEMS OF SENSITIVE AND RESISTANT CULTIVARS OF LENTIL Cicerali, Iin Nur M.Sc., Department of Biotechnology Supervisor: Prof. Dr. Meral Y&uuml / cel Co-supervisor: Asst. Prof. Dr. F&uuml / sun (nci) Eyidoan June 2004, 90 pages In this study, two lentil cultivars (Lens culinaris, Medik.) (ILL5582-salt tolerant and ILL590) were characterized and compared due to their NaCl susceptibility and antioxidant mechanism was examined under laboratory conditions. Physiological parameters such as wet-dry weight, root-shoot lengths, cell membrane stability, lipid peroxidation in terms of malondialdehyde (MDA), H2O2, proline contents were determined. The activities of antioxidant enzymes such as superoxide dismutase (SOD: EC 1.15.1.1), catalase (CAT: EC 1.11.1.6), ascorbate peroxidase (APX: EC 1.11.1.11) and glutathione reductase (GR: EC 1.6.4.2) were examined and analyzed in 14 days old plant seedlings after 9 days of normal growth and 5 days of 100mM and 200mM NaCl stress conditions. Shoot-root length and wet-dry weight percent decrease were more in ILL590. Especially shoot tissues were affected more from the stress conditions when compared to root tissues. ii According to malondialdehyde (MDA) content and membrane stability results, lipid peoxidation was higher in ILL590 and significant increases were observed in shoot tissues. Proline concentration showed a remarkable increase in salt concentration dependent manner. Higher concentrations of proline in ILL5582 might be the reason of higher salt tolerance when compared to ILL590. Among the antioxidant enzymes SOD was the one which showed highest activity increase. At organ level roots showed highest activity when compared to leaves. In the organelle higher activity percent contribution was achieved by cytosolic Cu/ZnSOD isozyme. Higher percent increase of this isozyme was observed in ILL5582. This might be one of the tolerance mechanisms that get activated against NaCl stress. APX activity showed similar alterations in both cultivars. In leaf tissues significant increase was observed but in root tissues ascorbate peroxidase activity did not change significantly. Glutathione Reductase activity increase was significant in both cultivars leaf tissues but although ILL5582 showed a stress concentration dependent increase, ILL590 did not. The activity of CAT enzyme in leaf and root tissues of both cultivars did not significantly change under increasing salt stress conditions. The results suggested that the leaves were more susceptible to salt stress. Also when two cultivars were compared ILL5582 was found to be more tolerant against salt stress than ILL590 under laboratory conditions and SOD enzyme seemed to be the most active component of the salt tolerant mechanism.

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