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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.
31

Produção de mudas por estaquia e cultivo protegido de maracujazeiro-amarelo. / Production of seedlings by cutting and protected cultivation of yellow passion fruit.

Torchelsen, Marcela de Melo 21 August 2013 (has links)
Made available in DSpace on 2014-08-20T13:25:38Z (GMT). No. of bitstreams: 1 dissertaao_marcela_torchelsen.pdf: 715805 bytes, checksum: bf1ab614e4add7f193d6e901a5a855d9 (MD5) Previous issue date: 2013-08-21 / To obtain high production and quality on cultivation of yellow passion fruits, is necessary environmental conditions, nutrition and appropriate management techniques, and the use of quality seedlings to form the orchard. This study aimed to evaluate the production of seedlings by cutting and protected cultivation of yellow passion fruit. This is described in three chapters, corresponding to the experiments. In the first chapter, the objective was to evaluate the cutting rooting three cultivars of yellow passion fruit (BRS Gigante Amarelo, BRS Ouro Vermelho and BRS Sol do Cerrado) using different doses of indolebutyric acid (0, 1000 and 2000mg L-1). 45 days after, were evaluated the percentage of rooted cuttings, the average length of the longest root, the percentage of cuttings with presence of leaf, the average number of roots per cutting and percentage of cuttings viable. The cultivars BRS Sol do Cerrado and BRS Gigante Amarelo had higher index of rooting. The use of IBA did not affect its rooting percentage, but the concentration of 2000mg L-1 provided the highest number of roots per cutting. In the second chapter, was evaluated the growth and biomass of seedlings of three cultivars of yellow passion fruit (BRS Gigante Amarelo, BRS Ouro Vermelho and BRS Sol do Cerrado) in hydroponic growing system and semi-hydroponic. Was evaluated the length of the shoots at 20, 40, 60 and 80 days, the mass of fresh matter and dry matter of shoots and roots. The semi-hydroponic system showed the biggest length of shoots at 80 days after transplanting. The mass of fresh matter of shoots was bigger in BRS Gigante Amarelo. The fresh and dry mass of shoot and dry mass of root were higher in the semi-hydroponic system. The fresh mass of roots was higher in seedlings of BRS Gigante Amarelo and BRS Ouro Vermelho in the semi-hydroponic system, and lower in the BRS Ouro Vermelho in the hydroponics. In the third chapter, were evaluated parameters relating to the development and production of plants and the physicochemical characteristics of the fruits of two cultivars of yellow passion fruit (BRS Gigante Amarelo and BRS Sol do Cerrado) in conditions of greenhouse in hydroponic systems type NFT, testing two types of systems of conduction (vertical espalier with two secondary branches and vertical espalier with four secondary branches). The plants of cv. BRS Gigante Amarelo showed higher amount of quaternaries branches and growth of trunk diameter, induced by the system with two secondary branches, and precocity of flowering. The system with four branches contributed to the harvest precocity and greater number of tertiary branches. Aspects concerning the production have not suffered influences of systems of conduction and cultivars. Plant cultivation with four branches did not increase the production. The physical and chemical characteristics on the fruits were not influenced by the conduction system, however the BRS Gigante Amarelo obtained higher medial length on fruits, thickness of peel and acidity in the juice. / No cultivo do maracujazeiro-amarelo, para obter alta produção e qualidade de frutos, é necessário condições ambientais, nutrição e técnicas de manejo adequadas, assim como a utilização de mudas de qualidade para formar o pomar. O presente trabalho teve como objetivo avaliar a produção de mudas por estaquia e o cultivo protegido do maracujazeiro-amarelo. O trabalho está descrito em três capítulos, equivalendo aos experimentos realizados. No primeiro capítulo, o objetivo foi avaliar o enraizamento de estacas de três cultivares de maracujazeiro-amarelo (BRS Gigante Amarelo, BRS Ouro Vermelho e BRS Sol do Cerrado) utilizando diferentes doses de ácido indolbutírico (0, 1000 e 2000mg L-1). Aos 45 dias, foram avaliados a porcentagem de estacas enraizadas, o comprimento médio da maior raiz, a porcentagem de estacas com presença de folha, o número médio de raízes por estaca e a porcentagem de estacas viáveis. As cultivares BRS Sol do Cerrado e BRS Gigante Amarelo apresentaram maior índice de enraizamento. O uso de AIB não influenciou a porcentagem de enraizamento, mas a concentração de 2000mg L-1 proporcionou maior número de raízes por estaca. No segundo capítulo, foi avaliado o crescimento e a biomassa de mudas de três cultivares de maracujazeiro-amarelo (BRS Gigante Amarelo, BRS Ouro Vermelho e BRS Sol do Cerrado) em sistema de cultivo hidropônico e semi-hidropônico. Foi avaliado o comprimento das brotações aos 20, 40, 60 e 80 dias, a massa da matéria fresca e seca da parte aérea e das raízes. O sistema semi-hidropônico apresentou o maior comprimento de brotações aos 80 dias após o transplante. A massa da matéria fresca da parte aérea foi maior na BRS Gigante Amarelo. A massa fresca e seca da parte aérea e a massa seca das raízes foram superiores no sistema semi-hidropônico. A massa fresca de raízes foi maior nas mudas das cultivares BRS Gigante Amarelo e BRS Ouro Vermelho no sistema semi-hidropônico, e menor na BRS Ouro Vermelho no hidropônico. No terceiro capítulo, foram avaliados parâmetros relativos ao desenvolvimento e produção das plantas e as características físico-químicas dos frutos de duas cultivares de maracujazeiro-amarelo (BRS Gigante Amarelo e BRS Sol do Cerrado) em condições de cultivo protegido em sistema hidropônico do tipo NFT, testando dois tipos de sistemas de condução (espaldeira vertical com dois ramos secundários e espaldeira vertical com quatro ramos secundários). As plantas da cv. BRS Gigante Amarelo apresentaram maior quantidade de ramos quaternários e crescimento do diâmetro do caule, induzidos pelo sistema com dois ramos secundários, e precocidade de florescimento. O sistema com quatro ramos contribuiu para a precocidade de colheita e maior número de ramos terciários. Os aspectos relativos à produção não sofreram influências dos sistemas de condução e cultivares. A condução da planta com quatro ramos não incrementou a produção. As características físicas e químicas dos frutos não foram influenciadas pelo sistema de condução, porém a BRS Gigante Amarelo obteve maior comprimento médio dos frutos, espessura média da casca e acidez no suco.
32

Mechanismy vývoje převodního systému srdečního u obratlovců / Mechanisms of conduction system development in vertebrates

Šaňková, Barbora January 2016 (has links)
Group of specialized cells that form cardiac conduction system is responsible for generation and coordinated propagation of the electrical impulse in the heart. Changes in its development can be connected with arrhythmias; therefore, a good level of knowledge is necessary and relevant for basic science and clinical practice. For correct development of the conduction system are important genes coding gap junctions proteins, ion channels, transcription factors and other molecules involved in signaling cascades (endothelin, neuregulin). Development of conduction system is determined in addition to genetic factors also by epigenetics and environmental factors. This thesis with its individual papers on which it is based is addressing different aspects of conduction system development, which appears to be a complex process. Another feature which is linking all papers together, is the methodological approach enabling us to study function of the conduction system - optical mapping. In the first publication we studied by the means of in vitro organ culture the impact of work load without interfering hemodynamics on the conduction system maturation in the chick embryonic heart. The phenotype observed during experiments was developmental regression of conduction system maturation together with changes in...
33

Localization of Cholinergic Innervation in Guinea Pig Heart by Immunohistochemistry for High-Affinity Choline Transporters

Hoover, Donald B., Ganote, Charles E., Ferguson, Shawn M., Blakely, Randy D., Parsons, Rodney L. 01 April 2004 (has links)
Objective: Previous studies have used acetylcholinesterase (AChE) histochemistry to identify cholinergic nerves in the heart, but this enzyme is not a selective marker for cholinergic neurons. This study maps cholinergic innervation of guinea pig heart using a new antibody to the human high-affinity choline transporter (CHT), which is present only in cholinergic nerves. Methods: Immunohistochemistry was used to localize CHTs in frozen and paraffin sections of heart and whole mount preparations of atrial ganglionated nerve plexus. AChE-positive nerve fibers were identified in sections from separate hearts for comparison. Results: Control experiments established that the antibody to human CHT selectively labeled cholinergic neurons in the guinea pig. CHT-immunoreactive nerve fibers and AChE-positive nerves were very abundant in the sinus and AV nodes, bundle of His, and bundle branches. Both markers also delineated a distinct nerve tract in the posterior wall of the right atrium. AChE-positive nerve fibers were more abundant than CHT-immunoreactive nerves in working atrial and ventricular myocardium. CHT-immunoreactive nerves were rarely observed in left ventricular free wall. Both markers were associated with numerous parasympathetic ganglia that were distributed along the posterior atrial walls and within the interatrial septum, including the region of the AV node. Conclusions: Comparison of labeling patterns for CHT and AChE suggests that AChE histochemistry overestimates the density of cholinergic innervation in the heart. The distribution of CHT-immunoreactive nerve fibers and parasympathetic ganglia in the guinea pig heart suggests that heart rate, conduction velocity, and automaticity are precisely regulated by cholinergic innervation. In contrast, the paucity of CHT-immunoreactive nerve fibers in left ventricular myocardium implies that vagal efferent input has little or no direct influence on ventricular contractile function in the guinea pig.
34

OPTICAL IMAGING OF EMBRYONIC CARDIAC CONDUCTION

Ma, Pei 13 September 2016 (has links)
No description available.
35

Vliv dávkování genu Nkx2.5 na vývoj a elektrofyziologii srdce u myši / Role of Nkx2.5 on development and electrophysiology of the mouse heart

Hámor, Peter January 2015 (has links)
Role of Nkx2.5 on development and electrophysiology of the mouse heart Prague 2015 Bc. Peter Hámor ABSTRACT The objective of this thesis is to investigate the role of Nkx2.5 gene dosage on electrophysiology of the mouse heart in prenatal stage of its development, in which the physiological functions of the heart fail to function properly. The main goal of this work is to search for differences in conduction of electric impulses through the embryonic mouse heart according to their genotype. Special method of capturing the conduction of electric impulse through myocardium was used for this purpose, called optical mapping. Thanks to this method I was able to construct images and videos capturing transition of the impulse with marked beginning of the activation and its direction in the heart. These outputs, or optical maps, help to define anomalies and defects compared with a normal functioning heart. The thesis focuses on the expression of the transcription factor Nkx2.5 and regulatory components related with the correct formation and physiology of the heart until 9.5 days post coitum. Individuals in this developmental stage were optically mapped and compared according to their genotypes - homozygous non-mutant, heterozygote and homozygous mutant mouse embryos exhibited some degree of similarity, while other...
36

Diencephalic and Mesencephalic Substrate for Brain Stimulation Reward

Fakhoury, Marc 04 1900 (has links)
No description available.
37

Role genu Nkx2.5 v morfogenezi a elektrofyziologii srdce u myši / Role of Nkx2.5 in development and electrophysiology of the mouse heart

Hámor, Peter January 2016 (has links)
Role of Nkx2.5 in development and electrophysiology of the mouse heart Prague 2016 Peter Hámor, B.S. ABSTRACT The objective of this thesis is to investigate the role of Nkx2.5 gene dosage on electrophysiology of the mouse heart in prenatal stage of its development. The main goal of this work is to search for differences in conduction of electric impulses through the embryonic mouse hearts of different genotype. Special method of capturing the conduction of electric impulse through myocardium, called optical mapping, was used to visualize the electrical activity. Thanks to this method I was able to construct images and videos capturing the spread of the impulse with identification of the beginning of the activation and its direction in the heart. These outputs, or optical maps, help to define anomalies and defects in mutants compared with a normal functioning heart. The thesis focuses on the expression of the transcription factor Nkx2.5 and regulatory components related with the correct formation and physiology of the heart until 9.5 days post coitum. Embryos at this developmental stage were optically mapped and analysed according to their genotype. While the wild type and heterozygote mouse embryos exhibited high degree of similarity, the homozygous mutants were dramatically different. Considering this work...
38

Porovnání parametrů pro stanovení srdeční asynchronie z vysokofrekvenčního signálu elektrokardiogramu / Comparing of the parameters for the determination of cardiac dyssynchrony from the ultra-high-frequency electrocardiogram

Jančová, Ivana January 2015 (has links)
This thesis deals with the analysis of high-frequency ECG, namely by parameters for the determination of cardiac asynchrony from the amplitude envelopes ultra-high-frequency ECG. In the theoretical part is described the conventional and high-frequency ECG, procedure of their scanning and parameters of the acquired record. Also is described the electrical conduction system of the heart and its blockade. This issue is followed by chapters about cardiac asynchrony and its treatments by biventricular pacemaker – resynchronization therapy. The chapter about resynchronization includes a description of the methods used for the indication for therapy based on conventional and high-frequency ECG. In the practical part are proposed new parameters for determining heart asynchrony from high-frequency ECG, programmed their detection in environment MATLAB and described realization of detection and obtained results. In the last part of thesis is described statistical evaluation of data and is decided about suitability of use the proposed parameters.
39

Detekce fibrilace síní v EKG / ECG based atrial fibrillation detection

Prokopová, Ivona January 2020 (has links)
Atrial fibrillation is one of the most common cardiac rhythm disorders characterized by ever-increasing prevalence and incidence in the Czech Republic and abroad. The incidence of atrial fibrillation is reported at 2-4 % of the population, but due to the often asymptomatic course, the real prevalence is even higher. The aim of this work is to design an algorithm for automatic detection of atrial fibrillation in the ECG record. In the practical part of this work, an algorithm for the detection of atrial fibrillation is proposed. For the detection itself, the k-nearest neighbor method, the support vector method and the multilayer neural network were used to classify ECG signals using features indicating the variability of RR intervals and the presence of the P wave in the ECG recordings. The best detection was achieved by a model using a multilayer neural network classification with two hidden layers. Results of success indicators: Sensitivity 91.23 %, Specificity 99.20 %, PPV 91.23 %, F-measure 91.23 % and Accuracy 98.53 %.
40

Shp2 deletion in post-migratory neural crest cells results in impaired cardiac sympathetic innervation

Lajiness, Jacquelyn D. January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Autonomic innervation of the heart begins in utero and continues during the neonatal phase of life. A balance between the sympathetic and parasympathetic arms of the autonomic nervous system is required to regulate heart rate as well as the force of each contraction. Our lab studies the development of sympathetic innervation of the early postnatal heart in a conditional knockout (cKO) of Src homology protein tyrosine phosphatase 2 (Shp2). Shp2 is a ubiquitously expressed non-receptor phosphatase involved in a variety of cellular functions including survival, proliferation, and differentiation. We targeted Shp2 in post-migratory neural crest (NC) lineages using our novel Periostin-Cre. This resulted in a fully penetrant mouse model of diminished cardiac sympathetic innervation and concomitant bradycardia that progressively worsen. Shp2 is thought to mediate its basic cellular functions through a plethora of signaling cascades including extracellular signal-regulated kinases (ERK) 1 and 2. We hypothesize that abrogation of downstream ERK1/2 signaling in NC lineages is primarily responsible for the failed sympathetic innervation phenotype observed in our mouse model. Shp2 cKOs are indistinguishable from control littermates at birth and exhibit no gross structural cardiac anomalies; however, in vivo electrocardiogram (ECG) characterization revealed sinus bradycardia that develops as the Shp2 cKO ages. Significantly, 100% of Shp2 cKOs die within 3 weeks after birth. Characterization of the expression pattern of the sympathetic nerve marker tyrosine hydroxylase (TH) revealed a loss of functional sympathetic ganglionic neurons and reduction of cardiac sympathetic axon density in Shp2 cKOs. Shp2 cKOs exhibit lineage-specific suppression of activated pERK1/2 signaling, but not of other downstream targets of Shp2 such as pAKT (phosphorylated-Protein kinase B). Interestingly, restoration of pERK signaling via lineage-specific expression of constitutively active MEK1 (Mitogen-activated protein kinase kinase1) rescued TH-positive cardiac innervation as well as heart rate. These data suggest that the diminished sympathetic cardiac innervation and the resulting ECG abnormalities are a result of decreased pERK signaling in post-migratory NC lineages.

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