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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

Participação do sistema nervoso parassimpático no metabolismo energético e na proliferação celular em ilhotas pancreáticas de ratos obesos-MSG

Lubaczeuski, Camila 01 August 2013 (has links)
Made available in DSpace on 2017-07-10T14:17:02Z (GMT). No. of bitstreams: 1 kelly Jaque.pdf: 1788989 bytes, checksum: 65d07041b0d9003d6666dd84d7fee873 (MD5) Previous issue date: 2013-08-01 / The growing number of overweight and obesity has led to an increase in the number of patients with insulin resistance and diabetes mellitus type 2. MSG obese rats were glucose intolerant, insulin resistant and theirs pancreatic islets secrete more insulin in response to glucose. Subdiafragmatic vagotomy changes the response of islets to glucose and improves glucose homeostasis, supporting the hypothesis that an unbalance of autonomic nervous system with increased parasympathetic nervous system (PNS) action but a decreased sympathetic nervous system function. Studies showed that the PNS is also involved in β-cell proliferation. Therefore, we investigated of PNS participation, using a subdiafragmatic vagal denervation, upon pancreatic β-cell function and mass regulation, and the body glucose control disruption in MSG-obese rats. For this, Male Wistar rats received during the first five days of life monosodium glutamate (MSG) or saline. Subdiaphragmatic vagotomy was performed at 30 days of life. At 90 days of age, we verified static insulin secretion, pancreas morphometric, ERK expression in islets, glucose homeostasis and lipidis. The MSG treatment caused obesity at 90 days of life. MSG rats presented lower body weight and nasoanal length, increased Lee index and fat depots, normoglycemia, hyperinsulinemia, dyslipidemia, glucose intolerance and insulin resistance when compared to CTL. Vagotomy performed at 30-days of age prevented obesity, fat deposition in the liver and ameliorated glucose tolerance and insulin sensitivity in adult MVAG rats in relation to MSG rats. Islets from MSG rats secreted more insulin at stimulatory glucose concentrations than CTL islets. Histological analysis showed that pancreatic islets from MSG rats were lower with a reduction in β-cell area without modification in α-cell content when compared with CTL. Also, MSG group presented an increased number of pancreatic islets per mm2, with higher number of islets, which may contributes to the higher islet and β-cell relative mass in the MSG pancreas. These effects were associated with enhanced proliferation in MSG group. The number of MVAG pancreatic islet were less than MSG. Vagotomoy performed at 30-days of age, reduced islet and β-cell area in the pancreas from 90-days old CVAG rats. Finally, the relative islet and β-cell mass in MVAG and CVAG rats was similar to CTL. Here we verified if ERK was involved in β-cell replication in MSG rats, but presented no alteration. We demonstrate for the first time that adult MSG rats showed enhanced pancreatic β-cell proliferation which contributes to the higher islet insulin secretion in response to glucose. The vagus nerve is the main factor involved in such a process, since vagotomy performed at 30 days of age prevented islet morphological alterations in adult MVAG rats. Possibly this increase PNS activity in MSG endocrine pancreas is responsible to hyperinsulinemia that enhanced fat storage, damaged glucose homeostasis and insulin action in MSG obesity / O crescente número de pessoas com sobrepeso e obesidade tem levado ao aumento no número de pacientes com resistência à insulina (RI) e portadores do Diabetes mellitus tipo 2. Ratos obesos MSG são intolerantes à glicose (Gli), RI e suas ilhotas pancreáticas secretam mais insulina em resposta à concentrações de Gli. A vagotomia subdiafragamática altera a responsividade das ilhotas à Gli e melhora a homeostase glicêmica nestes animais, sugerindo um desbalanço do sistema nervoso autonômico, com aumento do tônus parassimpático e redução do simpático. Estudos demonstram que o sistema nervoso parassimpático (SNP) possui efeito na proliferação das células β-pancreáticas. Desta forma, investigamos a participação do SNP, através da vagotomia subdiafragmática, no metabolismo energético e na proliferação das ilhotas e de células β-pancreáticas de ratos obesos-MSG. Para isto, ratos Wistar machos receberem durante os cinco primeiros dias de vida glutamato monossódico (grupo MSG) ou salina (grupo CTL). A vagotomia subdiafragmática foi realizada aos 30 dias de vida formando os grupos MVAG e CVAG. Aos 90 dias, verificamos a secreção estática de insulina, homeostase glicêmica e lipídica, morfometria do pâncreas e conteúdo proteico da ERK nas ilhotas. Ratos MSG apresentaram redução do peso corporal e comprimento nasoanal, aumento do índice de Lee e acúmulo de gordura, normoglicêmia, hiperinsulinemia, dislipidemia, intolerância à Gli e RI comparados aos CTL. A vagotomia realizada aos 30 dias de vida preveniu obesidade, acúmulo de gordura no fígado e melhorou a tolerância à Gli e a sensibilidade à insulina em ratos MVAG adultos em relação aos ratos MSG. As ilhotas dos animais MSG secretaram mais insulina quando estimulada pela Gli, em relação aos animais CTL. As análises histológicas mostram que as ilhotas pancreáticas dos animais MSG são menores com redução da área das células β sem alteração nas células α em relação aos CTL. O grupo MSG apresenta um aumento do número das ilhotas por mm2, que pode estar contribuindo com o aumento da massa relativa das ilhotas e das células β. Esse efeito está associado ao aumento da proliferação no grupo MSG. O número de ilhotas foi menor nos MVAG em relação aos MSG. A vagotomia realizada aos 30 dias de vida reduziu a área das ilhotas e das células β aos 90 dias de vida nos animais CVAG. Finalmente, a massa relativa das ilhotas e da células β no MVAG e CVAG foram similares ao CTL. Verificamos se a ERK estava envolvida na proliferação das células β nos ratos MSG, porém não apresentaram alterações desta proteína. Pela primeira vez demonstramos que ratos MSG apresentam aumento da proliferação das células β que contribui com o aumento da secreção de insulina em resposta à Gli. O nervo vago é o principal fator envolvido neste processo, visto que a vagotomia realizada aos 30 dias de vida preveniu as alterações morfológicas das ilhotas nos ratos MVAG adultos
12

Avaliação das citocinas inflamatórias em ratos obesos-msg suplementados ou não com taurina / Evaluation of inflammatory cytokines in obese rats supplemented or not with msg-taurine

Caetano, Luiz Carlos 10 November 2013 (has links)
Made available in DSpace on 2017-07-10T14:17:06Z (GMT). No. of bitstreams: 1 Luiz Caetano.pdf: 1961056 bytes, checksum: 05aefff53c5671351bad5763039bd60b (MD5) Previous issue date: 2013-11-10 / Among the several organic alterations arising from obesity, chronic inflammation is associated with the balance of cytokines TNF-α, IL-1β, IL-6, IL-2, IFNg, IL-4 and IL-10, and there is evidence the amino acid taurine (Tau) has anti-inflammatory effect. Therefore, this study investigated the inflammatory profile in plasma and retroperitoneal adipose tissue of MSG-obese rats, supplemented or not, with the TAU. Male Wistar rats received subcutaneous injections of MSG (4mg/kg body weight/day) or hyperosmotic saline during the first 5 days of life, composing the control (CON) and MSG groups. After 21 days, half of each group received TAU 2.5% in drinking water, and separated into 04 groups: CON, CON with TAU (CTAU), MSG and MSG with TAU (MTAU). At 120 days of age, the animals were euthanized. The MSG rats showed an increase in Lee Index, retroperitoneal and perigonadal fat pads deposition, insulin and triglycerides plasmatic concentrations and HOMA-IR, when compared to CON animals, showing that the treatment with MSG led to obesity. The TAU supplementation attenuated retroperitoneal fat deposition, as well as TG concentration. The MSG treatment did not alter the expression of JNK and IκBα. However, the supplementation with TAU increased 61% the expression of IkBα in CTAU group compared to the CON and 107% in the MTAU animals compared to the MSG. The expression of TNF-α, IL-1β and IL-6 in the retroperitoneal adipose tissue were similar in the four groups of animals, as well as plasma concentrations of TNF-α, IL-1β, IL-6, IL-2, IFNγ, IL-4 and IL-10. It is possible to conclude that neonatal treatment with MSG does not influence the inflammatory profile of the animals. We also conclude that the TAU increased 61% of IkBα protein expression in the control group and 107% in the MSG-obese animals, without affecting the inflammatory cytokines. Thus we suggest that TAU can exert their anti-inflammatory effects in adipose tissue, via NF-kB / Dentre as várias alterações orgânicas decorrentes da obesidade, está o processo inflamatório crônico associado ao balanço das citocinas TNF-α, IL-1β, IL-6, IL-2, IFNγ, IL-4 e IL-10, e, há evidências de que o aminoácido taurina (TAU) possui efeito anti-inflamatório. Assim, neste trabalho investigamos o perfil inflamatório plasmático e do tecido adiposo retroperitoneal de ratos obesos-MSG, suplementados ou não, com o aminoácido TAU. Ratos Wistar receberam injeções subcutâneas de MSG (4mg/kg de peso corporal/dia) ou salina hiperosmótica, durante os primeiros 5 dias de vida e foram distribuídos nos grupos MSG e CON, respectivamente. Após os 21 dias de vida, metade de cada grupo recebeu 2,5% de TAU na água de beber, sendo separados nos grupos CON, CON + TAU (CTAU), MSG e MSG + TAU (MTAU). Aos 120 dias de vida os animais foram eutanasiados. Ratos MSG apresentaram obesidade acompanhada de hipertrigliceridemia e resistência à insulina (RI). Todavia, não afetou a expressão de IκBα e JNK. A suplementação com TAU aumentou 61% a expressão do IkBα no grupo CTAU em relação ao grupo CON e 107% nos animais MTAU em comparação com os obesos-MSG. As expressões de TNF-α, IL-1β e IL-6 no tecido adiposo retroperitoneal foram semelhantes nos 4 grupos de animais estudados, assim como as concentrações plasmáticas do TNF-α, IL-1β, IL-6, IL-2, IFNγ, IL-4 e IL-10. É possível concluir que o tratamento neonatal com MSG não influencia o perfil inflamatório dos animais. Concluímos também que a TAU aumentou a expressão proteica do IkBα nos animais controle e MSG, sem afetar as citocinas inflamatórias. Desta forma sugerimos que a TAU possa exercer seus efeitos anti-inflamatórios no tecido adiposo, via NF-κB
13

Alterações no metabolismo lipídico hepático em ratos obesos submetidos à derivação duodeno-jejunal / Alterations in hepatic lipid metabolism in obese rats submitted to duodenal-jejunal bypass

Soares, Gabriela Moreira 30 January 2016 (has links)
Made available in DSpace on 2017-07-10T14:17:16Z (GMT). No. of bitstreams: 1 GABRIELA_ MOREIRA SOARES.pdf: 1940590 bytes, checksum: 743251bbcf008feeceea6700678f7e3f (MD5) Previous issue date: 2016-01-30 / Fundação Araucária / Hypothalamic obesity (HyO) is a severe condition without any effective therapy. Bariatric operations appear as an alternative treatment, but the effects of this procedure are controversial. Here, we investigated the effects of duodenal-jejunal bypass (DJB) upon lipid profile and expression of main genes, protein and transcription factors involved in hepatic lipid metabolism pathways in HyO rats. During the first 5 days of life, male newborn Wistar rats received a subcutaneous injection of monosodium glutamate (MSG) [4 g/kg body weight (BW), HyO group]. Control (CTL) group received saline [1.25 g/kg BW]. At 90 days of age, HyO rats were randomly submitted to DJB or sham operations forming HyO DJB and HyO Sham group, respectively. Six months after DJB, obesity parameters, lipids levels, and expression of genes and protein in the liver were verified. HyO Sham rats displayed obesity, hyperinsulinemia, insulin resistance, hypertryglyceridemic and presented higher free fatty acids (FFA) levels and hepatic triglyceride (TG) content. Also, HyO Sham animals enhanced acetyl-CoA carboxylase (ACC), fatty acid synthase (FASN) and stearoyl-CoA desaturase-1 (SCD-1) mRNA levels and ACC and FASN protein in the liver. Carnitine palmitoyltransferase-1a (CPT-1a) and microsomal TG transfer protein (MTTP) were down-regulated in HyO Sham rats. DJB operation normalized serum insulin, TG and FFA levels and hepatic TG content, without changing obesity in these animals. In addition, DJB reduced mRNA levels of liver pyruvate kinase (LPK), ACC, SCD-1, acyl-CoA oxidase (ACO) and carbohydrate response elemento-binding protein (ChREBP). ACC and FASN protein expression were normalized in HyO DJB animals. DJB reduces de-novo lipogenesis and improves hepatic TG content in HyO DJB rats, indicating that this surgery is efficient in the resolution of nonalcoholic fatty liver disease (NAFLD) in HyO. / A obesidade hipotalâmica (OH) é uma condição severa que não apresenta nenhuma terapia eficaz. Cirurgias bariátricas têm surgido como uma alternativa de tratamento, porém, os efeitos deste procedimento são controversos. No presente trabalho, investigamos os efeitos da derivação duodeno-jejunal (DDJ) sobre o perfil lipídico e sobre a expressão gênica de proteínas e fatores de transcrição envolvidos em vias do metabolismo lipídico hepático em ratos com OH. Durante os cinco primeiros dias de vida, ratos Wistar neonatos receberam uma injeção subcutânea de glutamato monossódico (MSG) [4 g/kg de peso corporal, grupo OH]. O grupo controle (CTL) recebeu solução salina [1,25 g/kg de peso corporal]. Aos 90 dias de idade, os ratos OH foram aleatoriamente submetidos à pseudo-cirurgia (PC) ou à DDJ, formando os grupos OH PC e OH DDJ, respectivamente. Seis meses após a DDJ, foram verificados, os parâmetros de obesidade, concentração de lipídios e expressão gênica e proteica no fígado. Ratos OH PC apresentaram obesidade, hiperinsulinemia, resistência à insulina, hipertrigliceridemia, concentrações elevadas de ácidos graxos livres (AGL) e do conteúdo de triglicerídeo (TG) hepático. Também, os animais OH PC tiveram aumento na quantidade de mRNA da acetil-CoA carboxilase (ACC), ácido graxo sintetase (FASN) e estearoil-CoA desaturase-1 (SCD-1) e da expressão proteica da ACC e FASN no fígado. A expressão gênica da carnitina palmitoil-transferase-1a (CPT-1a) e da proteína de transferência de triglicerídeos microssomal (MTTP) foram menores no fígado do grupo OH PC. A cirurgia de DDJ normalizou a concentração de insulina, AGL e TG séricos e o conteúdo de TG hepático, sem alterar a obesidade nesses animais. Além disso, a DDJ reduziu a expressão do mRNA da piruvato quinase hepática (LPK), ACC, SCD-1, acil-CoA oxidase (ACO) e da proteína de ligação do elemento responsivo à carboidratos (ChREBP). A expressão proteica de ACC e FASN foi normalizada em animais OH DDJ. A DDJ reduz a lipogênese de novo e melhora o conteúdo de TG hepático em ratos OH DDJ, indicando que esta cirurgia é eficiente na resolução da doença hepática gordurosa não alcoólica (DHGNA) na OH.
14

Validation of Remote Sensing Snow Cover Analysis

Geidne, Anna January 2005 (has links)
The by SMHI (Swedish Meteorological and Hydrological Institute) developed snow cover product, that analyses snow cover from satellite images, needs to be validated. A reliable validation method should be developed and concentrated to verify the snow cover analyses from images emerged from the recently operative European MSG-satellite. The validation is done for Europe, and this first validation test to evaluate the validation method is only done for a couple of clear days in March 2004. The snow cover analyses from the MSG images, computed by the snow cover product, are compared to synoptic snow observations and to a similar snow cover product from the NOAA project NESDIS. Every grid point of the MSG analysis area and the reference NESDIS area has been given a snow classification, describing the local status of the snow cover. The synoptic classification is derived from snow depth reports, stored in SMHI database. The product (MSG) classification and the reference classification in every grid point has then been added to a table and presented for manual evaluation. The most exacting work is to prepare the validation data to be comparable. The preparation quality affects the results, especially at the comparison to the synoptic source where the snow cover classification is a delicate problem. The synoptic reference data has shown up to be far too sparse to be used for a serious validation. There are also problems with the interpretation of the snow reports. Using the NESDIS source as reference the result looks better and the validation method is probably reliable. Images of the snow cover from MSG and NESDIS sources have also been sketched and compared. This comparison shows that the snow cover differences might originate from the snow cover product. The temperature of the ground might affect the snow detection; the snow is not detected sufficiently when ground is cold. On the other hand high altitude clouds seems possibly generate false snow detection. From the image comparison could also be presumed that forest might hide the snow cover. A more complete validation is now needed to draw any definitive conclusions if the existing snow cover differences originate from the snow cover product or from the validation method. But the method seems to work. Synoptic source is not recommended to use as validation reference, but the snow cover scenes from NESDIS seems to be a reliable reference source and works well for the validation method. / En produkt för beräkning av snötäckningsgrad har utvecklats av SMHI (Sveriges meteorologiska och hydrologiska institut). Produkten analyserar snötäcke utifrån satellitbilder och en tillförlitlig metod att validera produkten ska utvecklas. Valideringen som sedan ska göras, koncentreras till att verifiera snötäckesanalyser utifrån den nyligen operativa Europeiska MSG-satellitens bilder. Valideringen görs för Europa, och denna första testvalidering för att utvärdera valideringsmetoden görs för ett fåtal dagar med klart väder under mars 2004. Produktens snötäckesanalyser från MSG-satellitens bilder jämförs med synoptiska snöobservationer tillika analyser från en liknande produkt från amerikanska NOAAs projekt NESDIS. MSG- och NESDIS-analysernas snötäckesinformation finns lagrat i ett snöklassificeringsfält motsvarande den geografiska arean (Europa), där alla gridpunkter har tilldelats en klassificering vilket beskriver den lokala statusen på snötäcket i punkten. Snötäckesklassificeringen för de synoptiska observationerna görs utifrån snödjupsrapporter lagrade i SMHIs databas. De olika värdena på MSG-klassificeringen och referensklassificeringen i varje punkt summeras och presenteras i en tabell för utvärdering. Det mest krävande jobbet är att förbehandla indatat från de olika källorna för att få det jämförbart. Kvalitéten på förarbetet påverkar resultatet, speciellt vid jämförelsen mot synoptiska data där snötäckesklassificeringen är komplicerad. Resultattabellen tenderar att visa på ett bra resultat, men produkten för snötäckesanalys verkar ha svårt att detektera snö tillfredställande. Den synoptiska referenskällan har visat sig innehålla alldeles för lite data för att kunna användas i en seriös validering. Det finns även vissa problem med tolkningen av snörapporterna från databasen. Med NESDIS-produktens analys som referens ser resultatet bättre ut och valideringsmetoden kan sannolikt betraktas som tillförlitlig. En jämförelse mellan kartbilder över de två källornas klassificeringar har visat att det är möjligt att avvikelserna i beskrivningen av snötäcket beror på produkten för snötäckesanalys. Produktens snödetektering ser ut att kunna påverkas av marktemperaturen, snön upptäcks inte tillräckligt bra då marken är kall. Även höga moln ser ut att kunna påverka snödetekteringen och ger i så fall falskt klassificeringen snö där det enligt referenskällan är barmark. Utifrån bildjämförelsen kan också antas att skog kan gömma snötäcket. En mer komplett validering krävs för att dra några definitiva slutsatser om skillnaderna i snötäckningsgrad beror på valideringsmetoden eller på produkten för snötäckesanalys. Men metoden ser ut att kunna fungera. Synoptiska observationer rekommenderas inte att använda som referens, men snötäckesanalyser från NESDIS-projektets produkt verkar vara en tillförlitlig referens och fungerar väl för valideringsmetoden.
15

Participação do sistema nervoso parassimpático no metabolismo energético e na proliferação celular em ilhotas pancreáticas de ratos obesos-MSG

Lubaczeuski, Camila 01 August 2013 (has links)
Made available in DSpace on 2017-07-10T14:17:01Z (GMT). No. of bitstreams: 1 Camila.pdf: 1579699 bytes, checksum: 81aed6e2676f0085056d80a67c1ae83e (MD5) Previous issue date: 2013-08-01 / The growing number of overweight and obesity has led to an increase in the number of patients with insulin resistance and diabetes mellitus type 2. MSG obese rats were glucose intolerant, insulin resistant and theirs pancreatic islets secrete more insulin in response to glucose. Subdiafragmatic vagotomy changes the response of islets to glucose and improves glucose homeostasis, supporting the hypothesis that an unbalance of autonomic nervous system with increased parasympathetic nervous system (PNS) action but a decreased sympathetic nervous system function. Studies showed that the PNS is also involved in β-cell proliferation. Therefore, we investigated of PNS participation, using a subdiafragmatic vagal denervation, upon pancreatic β-cell function and mass regulation, and the body glucose control disruption in MSG-obese rats. For this, Male Wistar rats received during the first five days of life monosodium glutamate (MSG) or saline. Subdiaphragmatic vagotomy was performed at 30 days of life. At 90 days of age, we verified static insulin secretion, pancreas morphometric, ERK expression in islets, glucose homeostasis and lipidis. The MSG treatment caused obesity at 90 days of life. MSG rats presented lower body weight and nasoanal length, increased Lee index and fat depots, normoglycemia, hyperinsulinemia, dyslipidemia, glucose intolerance and insulin resistance when compared to CTL. Vagotomy performed at 30-days of age prevented obesity, fat deposition in the liver and ameliorated glucose tolerance and insulin sensitivity in adult MVAG rats in relation to MSG rats. Islets from MSG rats secreted more insulin at stimulatory glucose concentrations than CTL islets. Histological analysis showed that pancreatic islets from MSG rats were lower with a reduction in β-cell area without modification in α-cell content when compared with CTL. Also, MSG group presented an increased number of pancreatic islets per mm2, with higher number of islets, which may contributes to the higher islet and β-cell relative mass in the MSG pancreas. These effects were associated with enhanced proliferation in MSG group. The number of MVAG pancreatic islet were less than MSG. Vagotomoy performed at 30-days of age, reduced islet and β-cell area in the pancreas from 90-days old CVAG rats. Finally, the relative islet and β-cell mass in MVAG and CVAG rats was similar to CTL. Here we verified if ERK was involved in β-cell replication in MSG rats, but presented no alteration. We demonstrate for the first time that adult MSG rats showed enhanced pancreatic β-cell proliferation which contributes to the higher islet insulin secretion in response to glucose. The vagus nerve is the main factor involved in such a process, since vagotomy performed at 30 days of age prevented islet morphological alterations in adult MVAG rats. Possibly this increase PNS activity in MSG endocrine pancreas is responsible to hyperinsulinemia that enhanced fat storage, damaged glucose homeostasis and insulin action in MSG obesity. / O crescente número de pessoas com sobrepeso e obesidade tem levado ao aumento no número de pacientes com resistência à insulina (RI) e portadores do Diabetes mellitus tipo 2. Ratos obesos MSG são intolerantes à glicose (Gli), RI e suas ilhotas pancreáticas secretam mais insulina em resposta à concentrações de Gli. A vagotomia subdiafragamática altera a responsividade das ilhotas à Gli e melhora a homeostase glicêmica nestes animais, sugerindo um desbalanço do sistema nervoso autonômico, com aumento do tônus parassimpático e redução do simpático. Estudos demonstram que o sistema nervoso parassimpático (SNP) possui efeito na proliferação das células β-pancreáticas. Desta forma, investigamos a participação do SNP, através da vagotomia subdiafragmática, no metabolismo energético e na proliferação das ilhotas e de células β-pancreáticas de ratos obesos-MSG. Para isto, ratos Wistar machos receberem durante os cinco primeiros dias de vida glutamato monossódico (grupo MSG) ou salina (grupo CTL). A vagotomia subdiafragmática foi realizada aos 30 dias de vida formando os grupos MVAG e CVAG. Aos 90 dias, verificamos a secreção estática de insulina, homeostase glicêmica e lipídica, morfometria do pâncreas e conteúdo proteico da ERK nas ilhotas. Ratos MSG apresentaram redução do peso corporal e comprimento nasoanal, aumento do índice de Lee e acúmulo de gordura, normoglicêmia, hiperinsulinemia, dislipidemia, intolerância à Gli e RI comparados aos CTL. A vagotomia realizada aos 30 dias de vida preveniu obesidade, acúmulo de gordura no fígado e melhorou a tolerância à Gli e a sensibilidade à insulina em ratos MVAG adultos em relação aos ratos MSG. As ilhotas dos animais MSG secretaram mais insulina quando estimulada pela Gli, em relação aos animais CTL. As análises histológicas mostram que as ilhotas pancreáticas dos animais MSG são menores com redução da área das células β sem alteração nas células α em relação aos CTL. O grupo MSG apresenta um aumento do número das ilhotas por mm2, que pode estar contribuindo com o aumento da massa relativa das ilhotas e das células β. Esse efeito está associado ao aumento da proliferação no grupo MSG. O número de ilhotas foi menor nos MVAG em relação aos MSG. A vagotomia realizada aos 30 dias de vida reduziu a área das ilhotas e das células β aos 90 dias de vida nos animais CVAG. Finalmente, a massa relativa das ilhotas e da células β no MVAG e CVAG foram similares ao CTL. Verificamos se a ERK estava envolvida na proliferação das células β nos ratos MSG, porém não apresentaram alterações desta proteína. Pela primeira vez demonstramos que ratos MSG apresentam aumento da proliferação das células β que contribui com o aumento da secreção de insulina em resposta à Gli. O nervo vago é o principal fator envolvido neste processo, visto que a vagotomia realizada aos 30 dias de vida preveniu as alterações morfológicas das ilhotas nos ratos MVAG adultos.
16

Analysing Message Sequence Graph Specifications

Chakraborty, Joy 04 1900 (has links)
Message Sequence Charts are a visual representation of the system specification which shows how all the participating processes are interacting with each other. Message Sequence Graphs provide modularity by easily allowing combination of more than one Message Sequence Charts to show more complicated system behavior. Requirements modeled as Message Sequence Graphs give a global view of the system as interaction across all the participating processes can be viewed. Thus systems modeled as Message Sequence Graphs are like sequential composition of parallel process. This makes it very attractive during the requirements gathering and review phases as it needs inter-working between different stakeholders with varied domain knowledge and expertise – requirements engineers, system designers, end customers, test professionals etc. In this thesis we give a detailed construction of a finite-state transition system for a com-connected Message Sequence Graph. Though this result is fairly well-known in the literature there has been no precise description of such a transition system. Several analysis and verification problems concerning MSG specifications can be solved using this transition system. The transition system can be used to construct correct tools for problems like model-checking and detecting implied scenarios in MSG specifications. There are several contributions of this thesis. Firstly, we have provided a detailed construction of a transition system exactly implementing the message sequence graph. We have provided the detailed correctness arguments for this construction. Secondly, this construction works for general Message Sequence Graphs and not limited to com-connected graphs alone, although, we show that a finite model can be ensured only if the original graph is com-connected. Also, we show that the construction works for both synchronous and asynchronous messaging systems. Thirdly, we show how to find implied scenarios using the transition model we have generated. We also discuss some of the flaws in the existing approaches. Fourthly we provide a proof of undecidability argument for non com-connected MSG with synchronous messaging.
17

Continuing airworthiness policy and application to flying crane aircraft

Gao, Fei 01 1900 (has links)
This project is part of a collaborative MSc training programme between the Aviation Industries of China (AVIC) and Cranfield University, aiming at enhancing the competitiveness of AVIC in both international and domestic aviation market through applying continuing airworthiness policies in the whole aircraft development process. The arrangement of the research project is that all students start with a Group Design Project which is based on the Flying Crane Project provided by AVIC. Individual research projects will address some aspects of the Flying Crane Project during the Group Design Project, and then further developed during the period for individual projects. The aim of this research is to apply the airworthiness requirements and the methodology of the Maintenance Steering Group logic (MSG-3) in the Flying Crane Project. This is because that maintenance is one of the key factors of Continuing Airworthiness, and MSG-3 logic is the most accepted and approved method to develop scheduled maintenance for civil aircrafts. The main objectives of this project include: (1) To investigate current Continuing Airworthiness regulations, including European airworthiness requirements (as the main regulation to comply with) and Chinese airworthiness regulations (as an important reference and supplement to the research); (2) To investigate the main analysis methodology of reliability and maintainability, including Damage Tolerance and Failure Mode and Effect Analysis (FMEA); (3) To analyse the data resulted from the Group Design Project using MSG-3 logic to produce a set of Continuing Airworthiness instructions, for the operator and maintenance organisation of the aircraft, from the design organization’s perspective; (4) To develop Continuing Airworthiness instructions for airline operators to compose maintenance programmes for Flying Crane aircrafts, including maintenance tasks and intervals for the selected airframe systems and structural components; and (5) To identify applicable maintenance organisations in China for Flying Crane aircrafts in accordance with both European and Chinese airworthiness requirements. On completion of this research, two aspects of Continuing Airworthiness have been investigated, including maintenance programme and maintenance organization. With MSG-3 logic, the author developed the maintenance plan for three structural components (fuselage skin panel, wing root joint, and fin-fuselage attachment) and one airframe system (fuel system) based on results from the Group Design Project. The author also investigated the Chinese domestic aircraft maintenance companies, and selected suitable maintenance organizations based on technical and economical criteria.
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ESTIMATION DE L'ÉTAT HYDRIQUE DES SOLS EN AFRIQUE DE L'OUEST PAR TÉLÉDÉTECTION SPATIALE

Tran, Truong 21 October 2010 (has links) (PDF)
Les travaux réalisés au cours de cette Thèse ont contribué à améliorer l'estimation de l'humidité de surface du sol et de l'humidité racinaire sur la bande sahélienne en Afrique de l'ouest. La première partie a été consacrée à évaluer la capacité de différents algorithmes d'estimations de l'humidité du sol basées sur des mesures satellites dans le domaine spectral de l'infrarouge thermique. Dans un deuxième temps, une méthode a été développée dans le but d'obtenir une cartographie de l'humidité du sol à une résolution temporelle fine (< 3h) en se basant sur deux produits satellites: un produit satellite de précipitation et une cartographie journalière micro-onde sensible à l'humidité du sol. Dans un troisième temps, une évaluation de la fiabilité et de la robustesse de la méthodologie a été proposée. Enfin, une méthode semi-empirique a été utilisée afin de produire une cartographie de l'humidité de la zone racinaire (0-1 m) sur l'ensemble de la bande sahélienne. Les mesures de terrain obtenues sur trois sites situés au Mali, au Niger et au Bénin dans le cadre du programme AMMA ont servi de référence pour évaluer la qualité des estimations de l'humidité superficielle et racinaire à chaque étape de ce travail. Les résultats montrent qu'une estimation de l'humidité superficielle du sol est possible avec une précision de moins de 3 % vol. sur la bande sahélienne. L'erreur est de l'ordre de 5% vol. sur la zone soudanienne (Bénin). La précision est identique sur l'estimation de l'humidité racinaire. Enfin, la méthode développée permet parallèlement de corriger les produits satellites de précipitation et notamment la surestimation du cumul annuel et du nombre d'événements des trois produits satellites utilisés dans ce travail.
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Depression in people, that live with HIV in Lima / Depresión en personas que viven con VIH

Fasce Cayo, Ninoshka 25 September 2017 (has links)
The study investigates the depression in a group 55 adults (14 women and 41 men) who live with VJH, between 18 and 58 years, oflow and medium low socioeconomic leve! which attend public health centers, NGO and mutual support groups (MSG) of Lima. The Beck Depression Inventory was used to study the level of depression, as well as the five factors found in this population.The descriptive results were correlated with the following demographic variables: age,sex, time of diagnosis, the presence or absence of symptoms associated to VIH, the participationor not in a MSG, sexual orientation and sex. Results indicated that depression varies depending on whether the person belongs or not to a MSG, sex and sexual orientation. / El estudio investiga la depresión en un grupo 55 adultos (14 mujeres y 41 hombres) que viven con VIH, entre 18 y 58 años, de nivel socio económico bajo y medio bajo que acuden a centros de salud estatales, ONG y grupos de ayuda mutua (GAM) de Lima. Se uso el Inventario de Depresión de Beck para estudiar el nivel de depresión. así como los cinco factores encontrados en esta población. Se correlacionaron los resultados descriptivos con las siguientes variables demográficas: edad, sexo, tiempo de diagnóstico, presencia o no de síntomas asociados al VIH, participación o no en un GAM, orientación sexual y sexo. Los resultados indicaron que la depresión varía según la persona pertenezca o no a un GAM, el sexo y la orientación sexual.
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Plán prohlídek a údržby draku malého dopravního letounu s využitím moderních přístupů / Modern Maintenance Procedures for Airframe Inspections for General Aviation Category Aircraft

Koštial, Rostislav January 2017 (has links)
Aircraft scheduled maintenance requirements are rapidly extending and developing due to rapid evolution of small aircraft. This evolution leads to implementation of until recently exclusively airliner class maintenance standards. In the field of general aviation and FAR 23/ EASA CS-23 especially, preventive maintenance based on part replacing or repairing is still dominant. DAMAGE TOLERANCE philosophy implementation into an aircraft design influences maintenance procedures, which are adjusted to older SAFE LIFE philosophy. Aircraft manufactures are developing new ways, how to integrate requirements of damage tolerance application into scheduled maintenance procedures. Huge airliner manufactures (FAR 25/ CS-25) are using the ATA MSG-3 intelligent maintenance approach based on inspection. This dissertation thesis develops intelligent scheduled maintenance methodology, utilizing ATA MSG-3 procedures, expert knowledge and Multiple Criteria Decision Analysis (MCDA).

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