In an attempt to find a way of improving the damage tolerance of composite bonded repairs to metallic aircraft structures, the effect of using conventional crack growth retardation techniques in conjunction with bonded repairs was experimentally investigated. Hence, an experimental test program was set up to determine whether fatigue crack growth under bonded repairs is retarded further by giving the crack to be repaired a crack growth retardation treatment prior to repair patch application. In addition, it was set up to determine the influence of a bonded repair on the effectiveness of a crack growth retardation method. Centrally cracked aluminium plates were used. Stop drilling followed by cold hole expansion and the application of single overloads were selected as retardation treatments. Two patch materials were considered; boron/epoxy and Glare 2. Further test variables were the aluminium alloy and the plate thickness. Fatigue testing was carried out under constant amplitude loading and baseline results were determined first. In addition to optically monitoring the crack growth, local and global out-of-plane deformations were visualised with holographic interferometry and shadow moire??. Furthermore, the stress intensity factors under the repair patch were examined with strain gauges and measurement of the central crack opening displacement. Disbonds and fracture surfaces were studied after residual strength tests. The crack growth results obtained showed that retardation treatments decrease crack growth rates under a repair patch and that the effectiveness of a retardation treatment is increased by the patch. Although identical crack growth rates were observed under boron/epoxy and Glare 2 patches, the reinitiation period after the retardation treatment lasted longer when Glare 2 patches were applied. Analytical predictions of the extent of retardation based on existing models showed that the conjunctive effect of retardation treatments and bonded repairs was underestimated. A sustained reduction in crack growth rates was observed under bonded repairs with a prior overload retardation treatment. It was concluded that the damage tolerance of bonded repairs is increased by the application of a crack growth retardation treatment because the crack growth is retarded further. These findings indicate that the range of cracks in aircraft for which bonded repairs can be considered is expanded and that economic benefits can be obtained.

Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 4 uppsatser.

Thesis (Ph.D.) -- University of Adelaide, School of Paediatrics and Reproductive Health, Discipline of Obstetrics and Gynaecology, 2008. / "March 2008" Bibliography: leaves xxvi-xliii. Also available in print form.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 175-188). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 175-188). Also available on the Internet.

Introduction: fetal growth restriction, also called intrauterine growth restriction (IUGR) is a major complication of pregnancy. It is associated with high rates of perinatal morbidity and mortality and childhood, requiring high financial investments to enable adequate care for these newborns. Justification: need for a clinical and sonographic marker, through which one can predict the risk of a fetus likely to have impaired growth, enabling early, and better perinatal care intervention. Purpose: Check the relationship between the measure the placental volume obtained by antenatal ultrasonography, and immediately after birth by macroscopic in fetuses of pregnant women with suspected IUGR and low-risk pregnant women, and perinatal outcomes. Methods: Cross-sectional, prospective, observational study involving 30 low-risk pregnant women and 19 pregnant women of fetuses with suspected IUGR (weigth and/or waist circumference below the 10th percentile for gestational age), treated at Hospital Universitário de Santa Maria (HUSM). The antepartum placental volume, in cm3, was measured by the method described by Azpurua et al, which uses the measurements of length, height and thickness placenta; through the application provided by the same author, it was determined that percentile is the volume found for the given gestational age. The postpartum volume was measured by Archimedes Principle. Perinatal data were obtained from birth records and medical records of newborns. The measures of the variables were analyzed in the form of mean and standard deviation (parametric data), median and quartiles (nonparametric data). Statistical tests: t-Student, Mann-Whitney test, Pearson correlation; It was satisfactory a significance level of 5%, and the data stored and analyzed using the SPSS version 21.0. Results: There was a highly significant difference between the ultrasound and macroscopic placental volume in both groups (p<0,001); was a correlation between placental volume and Apgar in the first minute in the IUGR group (p<0,02); there was a highly significant association between admission to the neonatal intensive care unit, being higher in IUGR group (p<0,01); 94,7% of patients in the group IUGR had placentas with volume below the p10, used in the application. Conclusions: the volume of the placenta after delivery was lower than calculated before birth, in both groups, which is expected, due to the loss of blood through the placenta after placental delivery Adverse perinatal outcomes were present when the placental volume is small but that could be justified by prematurity. Thus, the findings of this study are suggestive of the placental volume in fetuses with IUGR is decreased and associated with few adverse perinatal outcomes. Studies with larger samples may confirm these assumptions. / Introdução: A restrição do crescimento fetal, também denominada crescimento intrauterino restrito (CIUR), é uma das principais complicações da gravidez. Está associada a elevados índices de morbimortalidade perinatal e na infância, requerendo investimentos financeiros elevados para possibilitar assistência adequada a esses recém-nascidos. Justificativa: Necessidade de pesquisa de marcador clínico-ecográfico, através do qual se possa predizer o risco de um feto vir a ter restrição do crescimento ou desfecho gestacional desfavorável, possibilitando intervenção precoce, e melhor assistência perinatal. Objetivos: Verificar relação entre a medida do volume placentário obtida pela ultrassonografia antenatal, e imediatamente após o nascimento pela macroscopia, em gestantes de fetos com suspeita de CIUR e gestantes de baixo risco, e os achados perinatais. Materiais e métodos: estudo transversal, prospectivo e observacional, realizado com 30 gestantes de baixo risco e 19 gestantes de fetos com suspeita de CIUR (peso fetal estimado e/ou circunferência abdominal abaixo do percentil 10 para a idade gestacional), atendidas no Hospital Universitário de Santa Maria (HUSM). O volume placentário anteparto, em cm3, foi mensurado pelo método descrito por Azpurua et al, que utiliza as medidas do comprimento, altura e espessura placentários; através do aplicativo disponibilizado pelo mesmo autor, determinou-se o percentil em que se encontrava o volume, para a determinada idade gestacional. O volume pós-parto foi medido pelo Princípio de Arquimedes. Dados perinatais foram obtidos dos registros de nascimento e prontuários dos recém-nascidos. As medidas das variáveis estudadas foram analisadas sob a forma de média e desvio padrão (dados paramétricos), mediana e quartis (dados não paramétricos). Testes estatísticos: t-Student, Mann-Whitney, correlação de Pearson; foi considerado satisfatório um nível de significância de 5%, e os dados armazenados e analisados no pacote estatístico SPSS versão 21.0. Resultados: houve diferença altamente significante entre o volume placentário ecográfico e macroscópico, em ambos os grupos (p<0,001); foi verificada correlação entre o volume placentário e o APGAR no primeiro minuto no grupo CIUR (p<0,02); existiu associação altamente significante entre internação na UTI-Neonatal, sendo maior no grupo CIUR (p<0,01); 94,7% das pacientes do grupo CIUR tinham placentas com volume abaixo do p10, no aplicativo utilizado. Conclusões: o volume da placenta no pós-parto foi menor que o calculado antes do nascimento, em ambos os grupos, o que é esperado, em razão da perda de sangue pela placenta após dequitação. Desfechos perinatais desfavoráveis estiveram presentes quando o volume placentário é pequeno, mas que poderiam ser justificados pela prematuridade. Assim, os achados do presente estudo são sugestivos de que o volume placentário em fetos com CIUR é reduzido, e associado a alguns desfechos perinatais adversos, mas estudos com amostras maiores são necessários para confirmar essas hipóteses.

O objetivo deste estudo foi comparar a morbidade e a mortalidade entre prematuros tardios (34 a 36 semanas e 6 dias de idade gestacional ao nascimento) com e sem restrição do crescimento fetal (RCF). O estudo foi desenvolvido longitudinalmente, envolvendo gestantes que apresentaram parto prematuro, sendo 50 com RCF (Grupo I) e 36, sem RCF (Grupo II), no período de outubro de 2004 a outubro de 2006. Foram avaliados os seguintes resultados pós-natais: peso e idade gestacional (IG) ao nascimento, cesárea, Apgar de quinto minuto, pH do sangue da artéria umbilical ao nascimento, necessidade e tempo de intubação orotraqueal (IOT) e de internação na unidade de terapia intensiva neonatal (UTI). Foram também avaliados: síndrome do desconforto respiratório (SDR), sepse, plaquetopenia, hipoglicemia, hemorragia intracraniana (HIC), icterícia e necessidade de fototerapia, tempo de internação e ocorrência de óbito. Para análise estatística foram utilizados os testes de Qui-Quadrado, exato de Fisher e teste não paramétrico de Kruskal Wallis, adotado nível de significância de 5%. As idades gestacionais avaliadas foram semelhantes nos dois grupos, com média de 35,5 semanas. Observou-se, no grupo I, maior freqüência dos seguintes resultados pós-natais adversos: menor peso ao nascimento (p<0,001), maior incidência de cesárea (92% versus 25% do grupo II; p<0,0001), maior necessidade de internação em UTI (58% versus 33%; p=0,041), maior tempo de internação (p<0,001) e de internação em UTI neonatal (p<0,001), maior ocorrência de HIC (12% versus 0; p=0,037), maior ocorrência de hipoglicemia (p= 24% versus 6%; 0,047) e maior tempo de fototerapia (p=0,005). Os grupos não apresentaram diferenças nos índices de Apgar, pH de cordão, IOT, SDR, plaquetopenia, sepse e icterícia. Não houve casos de doença de membrana hialina, displasia broncopulmonar, hemorragia pulmonar ou óbito neonatal. Pode-se concluir que o grupo de prematuros tardios com RCF apresentou mais complicações neonatais do que o grupo sem RCF / The objective of this study was to compare neonatal morbidity and mortality between late-preterm infants (gestational age at birth: 34 to 36 weeks and 6 days) with and without fetal growth restriction (FGR). A longitudinal study was conducted between October 2004 and October 2006 involving 50 pregnant women with pre-term delivery associated with FGR (group I) and 36 women with spontaneous preterm delivery not associated with FGR (group II). The following postnatal outcomes were evaluated: weight and gestational age at birth, cesarean section rate, 5-minute Apgar score, umbilical artery pH at birth, and need for and duration of orotracheal intubation and hospitalization in the neonatal intensive care unit (NICU), as well as the presence of respiratory distress syndrome (RDS), sepsis, thrombocytopenia, hypoglycemia, intracranial hemorrhage (ICH) and jaundice, need for phototherapy, length of hospital stay, and occurrence of death. The chi-square test, Fishers exact test and nonparametric Kruskal-Wallis test were used for statistical analysis, adopting a level of significance of 5%. Gestational age was similar in groups I and II, with a mean of 35.5 weeks in both groups. A higher frequency of the following adverse postnatal outcomes was observed in group I: lower birth weight (p<0.001), higher incidence of cesarean section (92% versus 25% in group II; p<0.0001), greater need for NICU treatment (58% versus 33%; p=0.041), longer hospital (p<0.001) and NICU stay (p<0.001), higher frequency of ICH (12% versus 0; p=0.037) and hypoglycemia (24% versus 6%; p=0.047), and longer duration of phototherapy (p=0.005). No differences in Apgar scores, cord pH, orotracheal intubation, RDS, thrombocytopenia, sepsis, or jaundice were observed between groups. There were no cases of hyaline membrane disease, bronchopulmonary dysplasia, pulmonary hemorrhage, or neonatal death. In conclusion, the group of late-preterm infants with FGR presented more neonatal complications than the group without FGR

Orientador: Vanda Maria Gimenes Gonçalves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-07T03:53:56Z (GMT). No. of bitstreams: 1 Brianeze_AnaCarolinaGamaeSilva_M.pdf: 2266577 bytes, checksum: 0438ce034e299c96f18820665012448d (MD5) Previous issue date: 2006 / Resumo: O objetivo deste estudo foi avaliar e comparar o desempenho mental e o controle motor em lactentes nascidos a termo, pequenos (PIG) ou adequados (AIG) para idade gestacional no 12º mês de vida. Estudo prospectivo durante o 1º ano de vida. A análise dos resultados foi realizada em um corte seccional no 12º mês de vida. Os recém-nascidos (RN) foram selecionados no Centro de Atenção Integral à Saúde da Mulher da Universidade Estadual de Campinas (Unicamp), entre Maio de 2000 e Julho de 2003. Para cada neonato PIG foram selecionados os dois próximos neonatos AIG. Foram incluídos nesta pesquisa: RN nascidos a termo, idade gestacional entre 37 e 41 semanas; peso de nascimento abaixo do percentil 10 para o grupo PIG ou entre os percentis 10 e 90 para o grupo AIG; residentes na região metropolitana de Campinas. O projeto foi aprovado pelo Comitê de Ética em Pesquisa da Unicamp. Foram excluídos RN com síndromes genéticas, malformações ou infecções congênitas diagnosticadas no período neonatal; peso de nascimento acima do percentil 90 e os que necessitaram de internação em unidade de terapia intensiva neonatal. Foram utilizadas as Escalas Bayley de Desenvolvimento Infantil II (BSID-II) (1993), aplicadas no 12º mês de vida, com ênfase em provas motoras de controle postural. Os dados registrados nos roteiros de avaliação foram transcritos e armazenados nos moldes de arquivo para o banco de dados do programa ¿Statistical Package for Social Sciences for Personal Computer¿ (SPSS/PC), versão 11 e analisados através do ¿Statistical Analysis System¿ (¿SAS System for Windows¿), versão 8.02. A população de 95 lactentes compareceu a pelo menos uma avaliação programada no 1º ano de vida e a amostra seccional avaliada no 12º mês foi composta por 70 lactentes (23 PIG e 47 AIG). No estudo da população, o grupo PIG apresentou peso ao nascimento significativamente menor que o grupo AIG. Os grupos apresentaram diferenças na distribuição de algumas variáveis maternas. A escolaridade menor que 8 anos esteve 3,71 vezes mais associada ao grupo PIG e a ocupação esteve 0,18 vezes mais associada ao grupo PIG. No estudo amostral, o grupo PIG apresentou peso ao nascimento significativamente menor que o grupo AIG. Ocupação materna foi 0,22 vezes mais associada ao grupo PIG. Os valores de ¿index score¿ na escala motora foram significativamente menores no grupo PIG (p= 0,046). No estudo do controle postural da amostra, observou-se diferença significativa entre os grupos, nas provas MO 61: fica em pé sozinho, (p= 0,019) e MO 71: caminha para o lado, (p= 0,020), com maior freqüência de execução no grupo AIG. Concluiu-se que lactentes nascidos PIG apresentaram pontuações significativamente mais baixas na escala motora, sendo que as provas: fica em pé sozinho e caminha para o lado, mostraram diferença significativa, executada por menor proporção de lactentes do grupo PIG / Abstract: The objective of this study was to assess and to compare the mental performance and motor control in infants born at term, small (SGA) or appropriate (AGA) for gestational age in the 12th month of life. It was a prospective study during the 1st year of life. The analysis of the results was done in a sectional cohort in the 12th month of life. The neonates were selected in the Center of Integral Attention to the Woman's Health at Universidade Estadual de Campinas (Unicamp) from May 2000 to July 2003. To each SGA neonate, the next two AIG neonates were selected. In this research were included: neonates at term, gestational age between 37 and 41 weeks, birth weight below the 10 percentile for the SGA group or between the 10 and 90 percentiles for the AGA group; living in the Campinas metropolitan area. Ethical permission was obtained from the Research Ethics Committee at Unicamp. Genetic syndromes, multiple congenital malformations or verified congenital infections; birth weight above the 90 percentile and those who needed neonatal intensive care were excluded. The Bayley Scales of Infant Development-II (BSID-II) (1993) were used in the 12th month of life, with emphasis in items for the motor postural control. The data registered in the record form were transcribed and stored in the data bank of the Statistical Package for Social Sciences for Personal Computer (SPSS/PC), version 11, and were analyzed through the Statistical Analysis System (SAS System for Windows), version 8.02. A population of 95 infants was assessed at least once in the 1st year of life. The sectional sample in the 12th month was composed of 70 infants (23 SGA and 47 AGA). In the population study, the SGA group showed birth weight significantly lower than the AGA group. There was difference in the distribution of some maternal variables. The scholarship below 8 years was 3.71 times more associated to the SGA group and the maternal occupation was 0.18 times more associated to the SGA group. In the sample study, the SGA group showed birth weight significantly lower than the AGA group. Maternal occupation was 0.22 times more associated to the SGA group. The motor index score was significantly lower in the SGA group (p= 0.046). In the study of the postural control of the sample, there was significant difference between the groups in the item MO 61: stands up alone (p= 0.019) and MO 71: walks sideways (p= 0.020), with lower frequency for the SGA / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas

Orientador: Jose Antonio Rocha Gontijo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-25T13:32:34Z (GMT). No. of bitstreams: 1 Custodio_AugustoHenrique_M.pdf: 4527903 bytes, checksum: 4f67c2ab2501e1bba65a4d2cf2320dfe (MD5) Previous issue date: 2014 / Resumo: A programação fetal é um processo fisiológico que assegura, durante o desenvolvimento intrauterino, a adaptação para o mundo exterior. Ou seja, o organismo é "moldável" por estímulos durante sua formação e dependendo do insulto experimentado, existe a possibilidade de mudanças estruturais e funcionais que podem predispor o indivíduo a doenças na vida adulta. O modelo de restrição proteica, assim como outros modelos, leva a um "stress" gestacional e, segundo a hipótese de Barker, programa a prole ao desenvolvimento de doenças na vida adulta, dentre elas a hipertensão arterial. Os rins são órgãos fundamentais na manutenção do equilíbrio hemodinâmico. Mudanças morfológicas e neuroendócrinas nos rins levam a alterações hidroeletrolíticas frequentemente associadas à patogênese da hipertensão arterial. A gênese desta doença ainda não está bem descrita, por envolver alterações multifatoriais, dentre elas, modificações da atividade neural tanto central quanto periférica, que podem ser um indicativo da elevação pressórica em nosso modelo. A atividade simpática renal é um importante modulador da excreção dos eletrólitos e, quando alterada, promove maior ou menor retenção de sais, principalmente o sódio, podendo contribuir para a elevação da volemia e consequentemente da hipertensão arterial. Diversos neuropeptídeos estão envolvidos na atividade simpática renal e os níveis destes são um importante marcador na gênese da hipertensão. Dentre esses peptídeos estão a Substância P (SP), seu receptor NK1R e o Peptídeo Relacionado ao Gene da Calcitonina (CGRP). Nossos resultados mostraram redução na imunorreatividade de SP, CGRP e aumento do receptor 1 para neurocinina nos gânglios da raiz dorsal da prole de ratas submetidas à restrição proteica gestacional. Identificamos também a elevação dos níveis de CGRP na parede pélvica renal. Assim, acreditamos que haja alterações na neuromodulação da atividade aferente renal, o que pode ser um fator contribuinte para a manutenção do estado hipertensivo neste modelo experimental / Abstract: A fetal programming is a physiologic process that ensures an adaptation for external world during the intra uterine development. In this period, the organism is "moldable" by stimulus that happens during its formation, which ensures adequate phenotypes formation for different environments. Kidneys are the most important organs when it has to do with maintaining the organism hemodynamic balance and also morphological and neuroendocrine alterations, which leads to fluid and eletrolytes changes, frequently associated to arterial hypertension pathogenesis. The genesis of this disease is not well described yet. It involves multifactorial changes like the neural activity in both central as peripheral, which, in our model, may be an indicative of increased pressure. The renal sympathetic activity is an important excretion modulator of electrolytes and when amended, promotes greater or lesser retention of salts, mainly sodium, contributing to the increase in blood volume and consequently hypertension. Several neuropeptides are involved in renal sympathetic activity, and these levels are an important marker in the genesis of hypertension. Among these peptides we find substance P (SP) and its receptor NK1R, and Related Peptide Calcitonin Gene (CGRP). Our research showed reduced immunoreactivity of SP, CGRP and increased neurokinin 1 receptor in dorsal root ganglia among the offspring of rats subjected to gestational protein restriction. According to this result, we believe that there are changes in afferent renal activity neuromodulation which may be a contributing factor for maintenance of hypertension in this experimental model / Mestrado / Medicina Experimental / Mestre em Ciências

The major physiological function of the carotid body is to respond to a low partial pressure of oxygen in the systemic arterial blood. The structure and functions of the adult carotid body have been extensively investigated over the past fifteen years. However, the carotid body in children has been relatively neglected with only a handful of studies being performed. To date, no study has been undertaken to investigate the effects of intrauterine hypoxia on the carotid body of foetuses. Clinically, intrauterine growth retardation has been ascribed, amongst other causes, to placental insufficiency that results in chronic hypoxia in the fetus. Intrauterine growth retardation can be divided into two types: - Type I (symmetrical) and type II (asymmetrical). In Type II intrauterine growth retardation, growth retardation does not become clinically evident until the third trimester. There is relative brain sparing with a greater deprivation in the size of abdominal organs, such as the liver and the kidneys. Previous studies have shown that there is no correlation between volume of the carotid body and hypoxia in children. However, Heath et al. made the observation that there are three variants of chief cells (progenitor, light and dark) within the carotid body and that an increase in the relative percentage of the dark subtype is an indicator of hypoxia. Using this observation, the present study set out to test two hypotheses: Firstly, whether the carotid body is functional in utero; and secondly whether there are any objective morphological changes in the carotid bodies of fetuses that have been subjected to intrauterine growth retardation. The carotid bodies from 72 fetuses with a gestational age between thirty and forty weeks were removed from the archived autopsy material, and differential cell counts were performed of the various cells present within the carotid bodies, using haematoxylin and eosin stained sections of the carotid bodies. The cases were assigned to three groups: - I) cases that had clinical and pathological evidence of intrauterine growth retardation, 2) negative controls and 3) positive controls. The three main groups were categorised as follows: -: (1) Intrauterine growth retardation (all cases with a weight for gestational age that is below the tenth centile and a brain to liver ratio of greater than four.) (2) Negative controls (all cases in whom there is a normal weight for age, a brain to liver ratio of less than three and no histological evidence of an episode of significant hypoxia before death). (3) Positive controls (all cases in whom there was clinically significant hypoxia present before death). The groups comprised of: 20 hypoxic positive controls, 15 negative controls, and 16 test cases which had suffered from intrauterine growth retardation. The remaining 21 cases were 7 dysmorphic infants, 3 congenital infection cases (congenital syphilis) and 11 cases that fitted the negative control criteria but had suffered significant hypoxia, thus excluding them from that category. The results showed that no significant difference was present in the percentage of sustentacular cells between any of the three groups. The results of the percentage of dark chief cells were as follows: l) mean percentage of dark chief cells in the intrauterine growth retardation group was 21.1 ±10.9%. 2) mean percentage of dark chief cells in the negative controls was 12.3 ±7.3%. 3) mean percentage of dark chief cells in the positive controls was 21.2 ±9.8%. A significant difference was present between the intrauterine growth retardation cases and the negative controls p=0.013, and between the positive and negative controls p=0.006. The dark chief cell count in the intrauterine growth retardation group showed no significant difference from the positive controls. No age-related difference appeared to be present in any of the groups. The conclusions reached are: a) Clinical hypoxia correlates with morphological changes in the carotid body, manifesting as an increase in the percentage of dark chief cells. b) intrauterine growth retardation cases show similar morphological changes in the carotid body to cases that have suffered from clinical hypoxia. c) therefore, by deduction intrauterine growth retardation fetuses have probably also been exposed to significant hypoxia while in utero. d) the fact that morphological changes in response to hypoxia are occurring in the carotid bodies of fetuses is an indication that the carotid body may be functional in utero. The results of the study indicate that a dark chief cell percentage of greater than 20% indicates that the fetus has been subjected to significant hypoxia, while a percentage of less than 10% indicates that it has not. A percentage of between 10 and 20% is unhelpful in determining whether hypoxia has taken place. The results of this study indicate that histological examination of the carotid bodies in neonates suspected of intrauterine growth retardation could be a useful additional means of assessment.