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1

Westerway, Susan Lyn Campbell. "Ultrasonic assessment of fetal size and growth." University of Sydney, 2006. http://hdl.handle.net/2123/2626.

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Doctor of Philosophy (Medicine)
This work investigates a number of issues. Firstly it examines ultrasonic fetal biometry, the parameters and techniques for accurate measuring and reviews the procedure adopted for graph formation and application of regression analysis for a mathematical model to describe the relationship between fetal size and weeks of gestation. Next it establishes new Australian fetal measurement charts for the crown rump length, head circumference and abdominal circumference, based on an Australian population, to replace the charts currently in use that are over 20 years old and relate to middle class white American and British women. The new graphs, along with previous work completed by the author in 1999 on the BPD, OFD femur and humerus length, were subsequently accepted by the Australasian Society for Ultrasound in Medicine (ASUM) in 2001 as the new Australian standard for ultrasonic fetal measurements. The accuracy of first trimester ultrasound dating is also investigated, displaying the variations seen in the crown-rump length due to fetal flexion and the implications of inaccurate measuring. The third study examines inter- and intra-sonographer ultrasonic fetal measurement reproducibility in the final 6 weeks of pregnancy. The study highlights the importance of sonographer competence, standardised measuring protocols, image planes and reference charts, particularly for patients undergoing ultrasound examinations for fetal growth assessment at different practices. The fourth study looks at the incidence of fetal macrosomia and birth complications in Chinese women and Caucasian women in two time periods, 1992 and 1999/2000. The results showed a rise in macrosomic babies born to Chinese immigrants from 4% of total Chinese births in 1992 to 9.8% in 1999/2000. There was also a rise in the rate of macrosomia among Caucasian women with respective rates of 11 and 14% for the same periods. The incidence of post partum haemorrhage increased significantly over this time in both Chinese immigrant and Caucasian women. Interventions declined in all Caucasian birth-weight ranges whilst interventions for Chinese births remained stable except between 3500grams and 4000grams, where interventions rose from 35.7% to 60.5%. Fetal macrosomia is a complication of pregnancy that is increasing in incidence. One of the causes of fetal overgrowth is uncontrolled gestational diabetes mellitus and so if women thus diagnosed are closely monitored, the risks of a macrosomic baby and associated birth complications may be reduced. The final study examines the effect of gestational diabetes mellitus (GDM) on fetal growth. GDM is a complication of mid to late pregnancy caused by glucose intolerance. In the Australian population up to 8% of all pregnancies can be affected. In the Australian Chinese community the GDM rate is as high as 15% compared with 4% in Caucasian women. The risks to the fetus as a result of GDM include increased perinatal mortality, large for gestational dates, macrosomia and prematurity. The aim of this study was to determine whether the fetuses of women diagnosed with GDM were significantly larger for dates for any of the commonly ultrasonically measured fetal parameters, than in the general pregnant population. The results show that if the glycaemic levels are properly controlled, fetal size should not be compromised. The abdominal circumference measurement appears to be the important marker for fetal macrosomia, particularly in the Chinese population. The study also assessed fetal weight gain from 36 weeks gestation to term in Caucasian women with GDM and Chinese pregnancies both with and without GDM. No statistically significant difference was seen in daily weight gain between the groups investigated.
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2

Westerway, Susan Lyn Campbell. "Ultrasonic assessment of fetal size and growth." Thesis, The University of Sydney, 2005. http://hdl.handle.net/2123/2626.

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This work investigates a number of issues. Firstly it examines ultrasonic fetal biometry, the parameters and techniques for accurate measuring and reviews the procedure adopted for graph formation and application of regression analysis for a mathematical model to describe the relationship between fetal size and weeks of gestation. Next it establishes new Australian fetal measurement charts for the crown rump length, head circumference and abdominal circumference, based on an Australian population, to replace the charts currently in use that are over 20 years old and relate to middle class white American and British women. The new graphs, along with previous work completed by the author in 1999 on the BPD, OFD femur and humerus length, were subsequently accepted by the Australasian Society for Ultrasound in Medicine (ASUM) in 2001 as the new Australian standard for ultrasonic fetal measurements. The accuracy of first trimester ultrasound dating is also investigated, displaying the variations seen in the crown-rump length due to fetal flexion and the implications of inaccurate measuring. The third study examines inter- and intra-sonographer ultrasonic fetal measurement reproducibility in the final 6 weeks of pregnancy. The study highlights the importance of sonographer competence, standardised measuring protocols, image planes and reference charts, particularly for patients undergoing ultrasound examinations for fetal growth assessment at different practices. The fourth study looks at the incidence of fetal macrosomia and birth complications in Chinese women and Caucasian women in two time periods, 1992 and 1999/2000. The results showed a rise in macrosomic babies born to Chinese immigrants from 4% of total Chinese births in 1992 to 9.8% in 1999/2000. There was also a rise in the rate of macrosomia among Caucasian women with respective rates of 11 and 14% for the same periods. The incidence of post partum haemorrhage increased significantly over this time in both Chinese immigrant and Caucasian women. Interventions declined in all Caucasian birth-weight ranges whilst interventions for Chinese births remained stable except between 3500grams and 4000grams, where interventions rose from 35.7% to 60.5%. Fetal macrosomia is a complication of pregnancy that is increasing in incidence. One of the causes of fetal overgrowth is uncontrolled gestational diabetes mellitus and so if women thus diagnosed are closely monitored, the risks of a macrosomic baby and associated birth complications may be reduced. The final study examines the effect of gestational diabetes mellitus (GDM) on fetal growth. GDM is a complication of mid to late pregnancy caused by glucose intolerance. In the Australian population up to 8% of all pregnancies can be affected. In the Australian Chinese community the GDM rate is as high as 15% compared with 4% in Caucasian women. The risks to the fetus as a result of GDM include increased perinatal mortality, large for gestational dates, macrosomia and prematurity. The aim of this study was to determine whether the fetuses of women diagnosed with GDM were significantly larger for dates for any of the commonly ultrasonically measured fetal parameters, than in the general pregnant population. The results show that if the glycaemic levels are properly controlled, fetal size should not be compromised. The abdominal circumference measurement appears to be the important marker for fetal macrosomia, particularly in the Chinese population. The study also assessed fetal weight gain from 36 weeks gestation to term in Caucasian women with GDM and Chinese pregnancies both with and without GDM. No statistically significant difference was seen in daily weight gain between the groups investigated.
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3

Connor, Jillian. "Measurement of, and relationship between, placental size and fetal cardiac development." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/397649/.

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Introduction -Fetal programming is the concept by which a fetus adapts to the intrauterine environment by altering blood flow to various organs which may induce permanent structural and/or functional change in those organs, altering disease susceptibility in later life. We hypothesised that the heart is a susceptible organ and that alterations in blood flow from the placenta in relation to maternal factors may have different effects on each side of the heart. We therefore aimed to assess the feasibility of measuring placental volume and growth, cardiac structure and cardiac function and assess the relationships between these measurements and also to maternal characteristics. Methods - We undertook a prospective, cross-sectional cohort study of low-risk women. 144 scans were performed on 127 women, 89 in the first trimester (10+6-13+6 weeks gestation) and 55 in the second trimester (18+0-20+6 weeks gestation). 17 of these women were scanned in both trimesters. Measurements performed were the left and right myocardial performance index to assess cardiac function and 3D placental volume. Second trimester cardiac structure was assessed by 2D measurements of total cardiac circumference, total ventricular circumference and internal left and right ventricular circumferences. These measurements were then correlated with each other, standard fetal biometry, maternal body composition, and birth and placental weights. Results - We developed reliable and reproducible techniques for measuring placental volume in the first and second trimester and relative cardiac chamber sizes in the second trimester, but had difficulty reliably measuring cardiac function by means of the myocardial performance index. We did not find any significant relationships between maternal body composition and fetal cardiac function or structure within our small cohort. Conclusions - Assessment of fetal cardiac function and structure in relation to maternal nutritional status and stress has the potential for detecting fetuses adapting to an adverse intra-uterine environment. This could assist identification of the maternal factors which lead to increased risk of disease in adult life and facilitate the development of targeted diet and lifestyle interventions.
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4

Grant, Simon Richard. "Influences on the fetal heart rate in mid-pregnancy and the relationship between fetal heart rate and size at delivery." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302344.

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5

MOHAMED, Nahid. "Comparison of Fetal Thymus Size in Normal and Preeclamptic Pregnancies: Is Thymus Size Smaller in Fetuses of Women with Preeclampsia?" Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/10003.

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Objective To determine whether the thymus is smaller in the fetuses of preeclamptic mothers than in those of normal controls. Methods This was a cross-sectional, prospective, comparative study of sonographically-determined fetal thymus measurements in 39 pregnancies with preeclampsia and 70 healthy pregnancies. Results Both the diameter and the perimeter of the fetal thymus were significantly smaller in pregnancies with preeclampsia than in healthy controls. The means of the thymus diameter were 28.6 ± 5.9 and 32.9 ± 4.5 mm and of the thymus perimeters 80.9 ± 16.5 and 93.1 ± 16.6 mm for preeclamptic and healthy pregnancies, respectively (P < 0.001). General linear models showed that smaller fetal thymuses in preeclamptic pregnancies were independent of gestational age, estimated fetal weight, small-for-gestational age status and antenatal steroid use. Conclusions Thymic involution appears to be a fetal response to preeclampsia, strengthening the evidence for the involvement of the immune system in the disease. Preeclampsia is associated with smaller fetal thymuses.
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6

Baird, Janis. "Birth size, blood pressure and glucose tolerance in twins : testing the fetal origins hypothesis." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341624.

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7

Adegoke, Korede K. "The Effects of Maternal Folate on Fetal Brain and Body Size among Smoking Mothers." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6793.

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The adverse effects of maternal smoking on infant mortality and morbidity has been well documented in the literature. Maternal tobacco use is causally associated with fetal growth restriction and correlates negatively with folate intake and metabolism. Studies have examined the association between smoking and folate levels during pregnancy, but very few have assessed this relationship using objective and accurate measures of both variables. Furthermore, despite evidence of a causal association between smoking in pregnancy and intrauterine growth restriction, and a plausible relationship between tobacco use and low maternal folate which is required for optimal fetal growth, no experimental study has investigated the potential benefit of folic acid in mitigating the adverse effects of maternal smoking on fetal outcomes. The objectives of this study were to investigate the relationship between maternal smoking and folate levels and examine the efficacy of higher-strength folic acid supplementation, in combination with enrollment in a smoking cessation program, in promoting fetal body and brain growth. Our hypothesis was that women who smoke during pregnancy have lower peri-conceptional folic acid reserves than non-smoker pregnant women and that folic acid reserves will decrease with increasing cotinine level. Additionally, smoker pregnant women on higher-strength folic acid (4mg daily) in combination with smoking cessation programs will experience faster fetal brain growth and have infants with larger body size at birth compared to smokers on the standard dose of folic acid (0.8mg daily). Participants were pregnant women (smokers and non-smokers) who received antenatal care between 2010-2014 at the Genesis Clinic of Tampa, a community health center affiliated with the Department of Obstetrics and Gynecology of the University of South Florida (USF). They were aged 18-44 years and had a gestational age of less than 21 weeks at study enrollment. To determine the peri-conceptional folic acid reserves in smoking versus nonsmoking women during pregnancy and associated sociodemographic factors, baseline (crosssectional) data from a double-blinded randomized controlled trial were analyzed using Tobit regression models (n=496). Smoking information was assessed using salivary cotinine, a sensitive and specific tobacco use biomarker. Folate reserve was measured using red blood cell folate. To investigate the efficacy of higher-strength folic acid on fetal body and brain size, baseline and follow-up data from pregnant smokers enrolled in the randomized controlled trial were utilized (n=345). All primary analyses of the clinical trial data were conducted on a modified intention-to-treat basis and included participants who completed the trial with an observed endpoint, irrespective of compliance to protocol. Multilevel modeling, linear regression, and log-binomial regression analyses were conducted. A significant inverse association between salivary cotinine level and periconceptional red blood cell folate concentration was found among pregnant women in the early to midpregnancy period. Smokers on high-dose folate during pregnancy had infants with a 140.38g higher birth weight than infants of their counterparts on standard dose folate (P =0.047). Mothers who received higher strength folate had a 31.0% lower risk of having babies with SGA compared to their mothers on the standard-dose (adjusted relative risk-ARR=0.69, 95% CI: 0.46–1.03; (P =0.073)). High-dose folate had no significant effect on the intrauterine rate of growth in head circumference, and head circumference and brain weight at birth in our trial sample. However, the brain-body ratio of infants of mothers who received high-dose treatment was 0.33 percentage-point lower than that for infants of mothers who received the standard dose of folate (P =0.044). Higher strength folic acid supplementation in pregnant women who smoke might be a cost-effective and safe option to improve birth outcomes and reduce low birth weight and SGA associated infant morbidity and mortality. Future studies with larger sample sizes and diverse populations are indicated to confirm or refute the results of this study. Randomized controlled trials starting during the preconception period and with follow-up until delivery are warranted, to identify the most folate-sensitive period of fetal growth and determine the optimal dose of folic acid supplement. Further research investigating several pathways through which the effects of prenatal smoking on adverse birth outcomes can be mitigated is needed.
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8

ISHIHARA, OSAMU, KENJI IKEBUCHI, CHIAKI SATO, ATSUO ITAKURA, MASAAKI HARA, and MACHIKO KIMURA. "FRAGMENT SIZE ANALYSIS OF FREE FETAL DNA IN MATERNAL PLASMA USING Y-STR LOCI AND SRY GENE AMPLIFICATION." Nagoya University School of Medicine, 2011. http://hdl.handle.net/2237/15355.

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9

Feldpausch, Julie Ann. "Effect of intralitter size on 60 and 95 day fetal myogenesis and development in the pig." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/20587.

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Master of Science
Department of Animal Sciences and Industry
Jim L. Nelssen
Piglet birth weight (BtW) is inextricably associated with preweaning survival. The non-linear antagonistic relationship between BtW and mortality risk is more severe in pigs <1.11 kg BtW than in pigs with BtW >1.11 kg. Thus, our research categorized fetal pigs as small (SM), median (MD), or large (LG) size depending on relative crown-rump length at d-60 gestation or BW within litter at d-95 gestation to evaluate differences in fetal myogenesis and development. At both d-60 and d-95, brain weights did not differ but brain weight:liver weight ratio was larger (P<0.05) for SM compared MD and LG. Cross-sectional area of the Longissimus muscle increased with increasing fetal size so that LG and MD had larger (P<0.05) whole muscle cross-sectional areas than SM although number of primary and relative secondary muscle fibers and their respective cross-sectional areas did not differ. Day-60 mRNA abundance of both IGF-1 and IGF-2 in SM was greater (P<0.05) than in MD and LG. Fetal size had a marginally significant effect (P=0.103) on gene expression of IGF-2 receptor with expression least in LG. Small fetuses had greater (P<0.05) d-60 MyoD gene expression and d-95 serum IGF-1 levels than MD and LG. Two experiments were conducted to determine the effects of feeding low or high doses of chlortetracycline (CTC) and antibiotic alternatives (pharmacologic Zn, Cu, and essential oil), alone or in combination, on nursery pig growth performance. Pharmacologic Cu (125 ppm from CuSO[subscript]4), Zn (2,000-3,000 ppm from ZnO), or increasing CTC level (0-441 ppm) improved growth performance additively while Origanum essential oil (0.005%) elicited no benefits and decreased G:F. Interactive effects of supplemental Cu (125 ppm), Zn (150 ppm), and ractopamine HCl (10 ppm for 28 d) on finishing pig growth performance, carcass characteristics, and antimicrobial susceptibility of enteric bacteria was evaluated. Ractopamine increased (P<0.001) ADG, G:F, HCW, percentage carcass yield, loin depth, percent fat-free lean, and decreased (P=0.014) backfat. Copper and/or Zn did not improve ADG, ADFI, or carcass traits. Fecal E. coli and Enterococcus bacterial resistance to most antibiotics decreased (P<0.05) over time or was stable for those that had a low baseline percentage of resistance.
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10

Bennini, Junior João Renato 1978. "Estimativa do peso do recem-nascido por meio de medidas ultrassonograficas bidimensionais e do volume da coxa fetal." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/313463.

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Orientadores: Cleisson Fabio Andrioli Peralta, Ricardo Barini
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-11-27T11:44:05Z (GMT). No. of bitstreams: 1 BenniniJunior_JoaoRenato_M.pdf: 1809698 bytes, checksum: 399e6ab502353af527e35953428d5e09 (MD5) Previous issue date: 2009
Resumo: Introdução: Alguns estudos demonstram que a predição do peso fetal usando a volumetria dos membros fetais é mais precisa do que quando se usam medidas bidimensionais (2D). Até hoje, somente o método multiplanar foi utilizado para a volumetria dos membros fetais. Desta forma, a utilidade do método rotacional (VOCAL®) para este fim nunca foi testada. Objetivos: Avaliar as variabilidades intra e interobservadores e a concordância entre as medidas do volume da coxa fetal realizadas com os métodos multiplanar e VOCAL®. Comparar as acurácias das fórmulas com medidas do volume da coxa fetal com as acurácias das fórmulas com medidas 2D. Comparar as acurácias das fórmulas deste estudo com as acurácias das fórmulas já publicadas. Métodos: 210 pacientes foram avaliadas, formando um grupo para gerar as fórmulas (n = 150) e um grupo para validá-las (n = 60). Os pacientes utilizados para gerar as fórmulas também foram utilizados para avaliar as variabilidades intra e interobservadores e a concordância entre as medidas realizadas pelos métodos multiplanar e VOCAL®. Foram utilizadas análises de regressão polinomial para criar uma equação com medidas 2D, uma com o volume da coxa fetal medido pelo método multiplanar (CoxaM) e uma com o volume da coxa fetal medido pelo método VOCAL® (CoxaV). Utilizaram-se testes t de Student pareados para comparar as acurácias das equações deste estudo com as acurácias das fórmulas já publicadas. Foram utilizadas análises proporcionais de Bland e Altman para avaliar as variabilidades intra e interobservadores e a concordância entre as medidas realizadas pelos métodos multiplanar e VOCAL®. Resultados: A diferença média percentual entre as medidas pelos métodos multiplanar e VOCAL® foi de -0,04 com limites de concordância de 95% de -8,17 e 8,09. A diferença média percentual e os limites de concordância de 95% entre as medidas na avaliação das variabilidades intra e interobservadores foram -1,10 (-7,67 to 5,47) e 0,61 (-7,68 to 8,91) para o método VOCAL® e 1,03 (-6,35 to 8,41) e -0,68 (-11,42 to 10,06) para o multiplanar. As melhores fórmulas para cálculo do peso fetal estimado (PFE) foram: PFE = -562.824 + 11.962 x CA x CF + 0,009 x DBP² x CA² (CA: circunferência abdominal; CF: comprimento femoral; DBP: diâmetro biparietal); PFE = 1033.286 + 12.733 x CoxaM; PFE = 1025.383 + 12.775 x CoxaV. Tanto no grupo que gerou as fórmulas como no grupo utilizado para validá-las não houve diferença significativa entre as acurácias das fórmulas com medidas 2D ou tridimensionais (3D). Quando aplicadas nas pacientes deste estudo, as acurácias das fórmulas 2D e 3D já publicadas foram significativamente piores dos que as das novas fórmulas. Conclusões: Os métodos VOCAL® e multiplanar são intercambiáveis para a volumetria da coxa fetal. Possivelmente as maiores fontes de discrepâncias na estimativa do peso fetal são as diferenças fenotípicas entre as pacientes utilizadas para criar as fórmulas. Os dados deste estudo reforçam a necessidade de fórmulas específicas para cada população, independentemente do uso de medidas 2D ou 3D.
Abstract: Introduction: Some authors have demonstrated that the prediction of birth weight using fetal limb volumetry is more precise than with two-dimensional ultrasound (2DUS). To date, only the multiplanar method has been used for fetal limb volumetry, so the usefulness of the rotational technique (VOCALTM - Virtual Organ Computer- aided AnaLysis) for this purpose has never been tested. Objectives: To evaluate the repeatability, reproducibility and agreement of measurements performed with multiplanar and VOCALTM techniques for total fetal thigh volumetry. To compare the accuracies of birth-weight-predicting models with total fetal thigh volumetry with models derived from 2DUS parameters. To compare the performances of our new formulas with those of previously published equations. Methods: 210 patients were prospectively evaluated to compose a formula-generating group (n = 150) and a prospective-validation group (n = 60). The patients of the formula-generating group were also used to evaluate the repeatability, reproducibility and the agreement of the measurements of multiplanar and VOCALTM techiniques for fetal thigh volumetry. Polynomial regression analysis was performed in the formula-generating group to generate one equation with 2DUS measurements, one with fetal thigh volume measured by the multiplanar technique (ThiM) and one with fetal thigh volume obtained by the VOCALTM method (ThiV). Paired samples t-tests were used to compare the accuracies of our equations with those of previously published 2D and three-dimensional (3D) equations. Proportionate Bland and Altman analyses were performed to determine the agreement between the two methods and to evaluate intra- and inter-observer variability. Results: The mean percentage difference between measurements performed with the VOCALTM and multiplanar techniques was -0.04 and the 95% limits of agreement were -8.17 and 8.09. The mean percentage difference and 95% limits of agreement between paired measurements in the assessment of intra- and inter-observer variability were -1.10 (-7.67 to 5.47) and 0.61 (-7.68 to 8.91) for the VOCALTM technique and 1.03 (-6.35 to 8.41) and -0.68 (-11.42 to 10.06) for the multiplanar method. The formulas with the best fit for the prediction of birth weight (EFW) were: EFW = -562.824 + 11.962 x AC x FL + 0.009 x BPD² x AC² (AC: abdominal circumference; FL: femur length; BPD: biparietal diameter); EFW = 1033.286 + 12.733 x ThiM; EFW = 1025.383 + 12.775 x ThiV. For both the formula-generating and the rospective-validation groups, there was no significant difference between the accuracies of the new 2DUS and 3DUS models. When applied to our population, the accuracies of previously published 2DUS and 3DUS formulas were significantly worse than our models. Conclusions: The VOCALTM and multiplanar techniques can be used interchangeably for total fetal thigh volumetry. We believe that the greatest sources of discrepancies in estimation of birth weight are the phenotypic differences among patients used to create each of the formulas mentioned in this study. Our data reinforce the need for customized birth weight prediction formulas, regardless of whether 2DUS or 3DUS measurements are employed.
Mestrado
Tocoginecologia
Mestre em Tocoginecologia
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11

Vaughn, Mathew Alan. "Characterization of intra-litter variation on myogenic development and myogenic progenitor cell response to growth promoting stimuli." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34595.

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Doctor of Philosophy
Department of Animal Sciences and Industry
John M. Gonzalez
This series of studies focuses on the impact of intra-litter variation on fetal myogenesis, and the ability of porcine progenitor cells to respond to growth promoting stimuli. In study 1, the smallest (SM), median (ME), and largest (LG) male fetuses from each litter were selected for muscle morphometric analysis from gilts at d-60 ± 2 and 95 ± 2 of gestation. On d-60 and 95 of gestation LG fetuses had greater whole muscle cross-sectional area (CSA) than ME and SM fetuses, and ME fetuses had greater whole muscle CSA than SM fetuses. Indicating that SM and ME fetuses are on a delayed trajectory for myogenesis compared to LG fetuses. At d-60 the advanced trajectory of LG compared to ME fetuses was due to increased development of secondary muscle fibers; whereas, the advanced myogenic development of LG and ME fetuses compared to SM fetuses was due to the presence of fewer primary and secondary muscle fibers. At d-95 of gestation the advanced myogenic development of LG and ME was due to increased hypertrophy of secondary muscle fibers. For study 2, porcine fetal myoblasts (PFM) were isolated from SM, ME, and LG fetuses from d-60 ± 2 of gestation fetuses and for study 3, porcine satellite cells (PSC) were isolated from the piglet nearest the average body weight of the litter. Both myogenic cell types were utilized to evaluate effects of porcine plasma on proliferation, differentiation, and indications of protein synthesis. For the proliferation assay, cells were exposed to one of three treatments: high serum which consisted high-glucose Dulbecco's Modified Eagle Medium supplemented with 10% (vol/vol) fetal bovine serum, 2% (vol/vol) porcine serum, 100 U penicillan/mL, 100 µg of strepmycin/mL, and 20 µg of gentamicin/mL (HS), low serum which consisted of HS without 10% FBS (LS), and LS supplemented with 10% (wt/vol) porcine plasma (PP). Treatments for the differentiation and protein synthesis assays consisted of either HS or LS media that either contained porcine plasma at 10% (wt/vol; PPP) or 0% (wt/vol; PPN). The HS-PFM had a greater proliferation rate compared to the LS and PP-PFM, and PP-PFM had a greater proliferation rate compared to LS-PFM. The LG fetuses’ PFM had a reduced proliferation rate compared to SM and ME fetuses’ PFM, which were similar. The PPP-PFM had a decreased myotube diameter compared to PPN-PFM. Small fetuses’ PFM had a greater myotube diameter compared to ME and LG fetuses’ PFM, and ME fetuses’ PFM had a greater myotube diameter compared to LG fetuses’ PFM. The proliferation rate of PP-PSC was decreased compared to the HS- and LS-PSC, and HS-PSC had a greater proliferation rate compared to LS-PSC. The PPP-PSC had greater differentiation capacity and myotube diameter than PPN-PSC. In conjunction these results indicate divergent myogenic development among different fetal sizes within a litter and suggest that porcine plasma supplementation stimulates myogenic progenitor cell activity in an age specific manner.
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12

Dreyer, Carlien. "Fruit set and fruit size studies on ‘Forelle’ and ‘Abate Fetel’ pear (Pyrus communis L.)." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79870.

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Thesis (MScAgric)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: Maintaining constant high yields in „Abate Fetel‟ and „Forelle‟ orchards in South Africa is challenging. Improving productivity in these orchards could be achieved by increasing fruit set and fruit size. Fruit size is an important marketing and quality parameter and has a significant effect on the economic value of fruit. Various protocols to improve fruit set are used by South African producers but these are not well researched. We therefore evaluated different combinations of plant growth regulators including gibberellic acid (GA3), gibberellins 4+7 (GA4+7), GA4+7 combined with 6-benzyladenine (6-BA), aminoethoxyvinylglycine (AVG) and prohexadione-calcium (P-Ca) in combination with trunk girdling during flowering on „Forelle‟ and „Abate Fetel‟ to determine the best fruit set strategy. All applied growth regulators improved fruit set relative to an untreated control over two consecutive seasons, but GA3 and P-Ca reduced return bloom and AVG resulted in smaller fruit size relative to the other treatments. The application of synthetic cytokinins are believed to enhance fruit size by stimulating and extending the cell division period in fruit when applied at the correct stage of fruit growth. In addition, combination of P-Ca with GA4+7 was used successfully on Japanese pear (Pyrus pyrifolia Nakai) and „Bing‟ sweet cherry to improve fruit size. This combination of GA4+7 and P-Ca was evaluated and combined with 6-BA treatments on European pear (Pyrus communis L.) cultivars, Forelle and Abate Fetel, to see if a similar effect on fruit size could be achieved under South African growing conditions. On both „Forelle‟ and „Abate Fetel‟ the combination of GA4+7 and P-Ca increased fruit size, but was more pronounced in „Abate Fetel‟. Growth regulators N-phenyl-N‟ -1,2,3-thiadiazol-5-ylurea (TDZ), N (2-chloro-4-pyridyl)-N‟ -phenylurea (CPPU), 6-BA and 2,4-dichlorophenoxyacetic acid (2,4-D) successfully increased fruit size in pear cultivars Coscia and Spadona in Israel. These growth regulators were applied to „Forelle‟ and „Abate Fetel‟ to determine if a similar effect could be achieved. None of the synthetic cytokinins applied had a significant effect on increasing fruit size in these two cultivars over two consecutive seasons although 6-BA increased return bloom and 2,4-D application resulted in increased fruit set. The stage when the cell division period in „Forelle‟ and „Abate Fetel‟ ends was also determined as 34 and 45 days after full bloom respectively, which can be used in the future to better plan the timing of fruit size enhancement treatments. Based on results from various fruit set and fruit size improvement trials, it can be recommended to use GA4+7 or AVG to increase fruit set on „Forelle‟ and „Abate Fetel‟, depending on the fruit set history of the orchard. Results from fruit size improvement trials were variable, and emphasises the fact that a balance between yield and fruit size must be determined for an orchard to achieve good fruit size and maximum return.
AFRIKAANSE OPSOMMING: Die handhawing van konstante, hoë opbrengste in „Abate Fetel‟ en „Forelle‟ boorde in Suid-Afrika is 'n uitdaging. Produktiwiteit in hierdie boorde kan verhoog word deur vrugset en vruggrootte te verbeter. Vruggrootte is 'n belangrike bemarkings- en kwaliteitsparameter en het 'n betekenisvolle effek op die ekonomiese waarde van vrugte. 'n Verskeidenheid protokolle om vrugset te verbeter word deur Suid-Afrikaanse produsente gevolg, maar hierdie protokolle is nog nie goed nagevors nie. Verskillende kombinasies van plantgroeireguleerders insluitend gibberelliensuur (GA3), gibberellien 4+7 (GA4+7), GA4+7 in kombinasie met 6-bensieladenien (6-BA), aminoetoksievinielglisien (AVG) en prohexadioon-kalsium (P-Ca) in kombinasie met stamringelering is aan „Forelle‟ en „Abate Fetel‟ bome gedurende blomtyd toegedien om die beste vrugsetstrategie te bepaal. Alle plantgroeireguleerdes wat toegedien is het vrugset verbeter relatief tot 'n onbehandelde kontrole oor twee opeenvolgende seisoene, maar GA3 en P-Ca het die aantal blomme in die daaropvolgende seisoen verlaag en AVG het kleiner vruggrootte gelewer relatief tot alle ander behandelings. Dit is wel bekend dat die toediening van sintetiese sitokiniene vruggrootte verbeter deur die stimulering en bevordering van seldeling in vrugte wanneer dit in die regte groeifase toegedien word. Die kombinasie van P-Ca en GA4+7 was suksesvol om vruggrootte te verbeter toe dit aan Japanese pere (Pyrus pyrifolia Nakai) en „Bing‟ kersies toegedien is. Hierdie kombinasie van GA4+7 en P-Ca is geëvalueer en gekombineer met 6-BA-behandelings op die Europese peer (Pyrus communis L.) kultivars, Forelle en Abate Fetel, om te bepaal of dieselfde effek op vruggrootte bereik kan word onder Suid-Afrikaanse groei kondisies. Op beide „Forelle‟ en „Abate Fetel‟ het die kombinasies van GA4+7 en P-Ca vruggrootte verbeter, maar dit was meer opmerklik in die geval van „Abate Fetel‟. Die groeireguleerders N-feniel-N‟ -1,2,3-thiadiazol-5-ylurea (TDZ), N (2-chloro-4-piridiel)-N‟ -fenielurea (CPPU), 6-BA en 2,4- dichloorfenoksieasynsuur (2,4-D) het vruggrootte verbeter in „Coscia‟ en „Spadona‟ pere in Israel. Hierdie plantgroeireguleerders is toegedien aan „Forelle‟ en „Abate Fetel‟ om vas te stel of dieselfde effek verkry kon word. Nie enige van die sintetiese sitokiniene wat toegedien is het 'n betekenisvolle effek op die verbetering van vruggrootte in hierdie twee kultivars oor twee opeenvolgende seisoene getoon nie, alhoewel 6-BA die verbetering van blom in die daaropvolgende seisoen tot gevolg gehad en 2,4-D vrugset verbeter het. Die stadium waar seldeling in „Forelle‟ en „Abate Fetel‟ eindig is vasgestel as 34 en 45 dae na volblom, onderskeidelik, wat in die toekoms gebruik kan word om die beplanning en tydsberekening van vruggrootte behandelings te verbeter. Na verskeie vrugset en vruggroote verbeterings proewe, kan aanbeveel word dat GA4+7 of AVG gebruik kan word om vrugset in „Forelle‟ en „Abate Fetel‟ te verbeter, afhangende van die vrugset geskiedenis van die boord. Resultate van vruggrootte verbeterings proewe het gevarieër en beklemtoon net weer die feit dat 'n balans tussen opbrengs en vruggrootte bepaal moet word om optimale vruggrootte te handhaaf en so hoë winste te verseker.
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13

Lapan, Ariya. "Melanoma Cell Adhesion Molecule is Associated with Myogenicity in Multiple Progenitor Populations within Human Fetal Skeletal Muscle." Thesis, Harvard University, 2011. http://dissertations.umi.com/gsas.harvard:10039.

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Skeletal muscle (SkM) possesses an impressive ability to regenerate in response to injury or chronic disease. This regenerative capacity is attributed to its resident mononuclear myogenic progenitors. Previous studies have identified several types of myogenic progenitors within SkM, some of which are isolated by fluorescence activated cell sorting (FACS) using cell surface markers. Studies in our laboratory have identified melanoma cell adhesion molecule (MCAM) as a cell surface marker expressed by myogenic progenitors in human fetal SkM. However, the relationship between MCAM expression and the degree of myogenic commitment of distinct MCAM+ populations has not been elucidated. In the present study, subpopulations of MCAM+ cells were purified by FACS on the basis of Hoechst 33342 dye uptake. Specifically, MCAM+ side population (SP) was isolated by Hoechst exclusion and MCAM+ main population (MP) on Hoechst incorporation. Sorted populations were first optimized for growth in vitro since SkM SP cells are difficult to maintain in culture. In particular, Invitrogen’s StemPro® MSC SFM medium was found to support propagation of human fetal SkM SP cells with minimal differentiation. Following this optimization, sorted populations were assessed for expression of myogenic markers before and after propagation and then for fusion potential in vitro and engraftment potential in vivo. The MCAM+ subpopulations were found to express myogenic markers to a significantly greater extent than MCAM- subpopulations. Furthermore, the MCAM+ subpopulations fused robustly into myotubes in vitro whereas the MCAM- subpopulations did not. Interestingly, the MCAM+ SP population exhibited the highest fusion potential in vitro and was the only MCAM+ subpopulation to engraft into dystrophic muscle in vivo following propagation. These results indicate that MCAM is associated with myogenicity and can be used to prospectively isolate a pure myogenic fraction from human fetal SkM tissue. Moreover, the MCAM+ SP retain its myogenic potential to a greater extent than MCAM+ MP after propagation. This suggests that the MCAM+ SP fraction contains a higher percentage of early myogenic progenitors compared to the MCAM+ MP fraction. Additional studies on MCAM-expressing populations in human fetal SkM may elucidate a potent population for use in cell-based therapeutic strategies for treating muscle diseases.
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Broncy, Lucile. "Isolement et caractérisation moléculaire de cellules rares circulantes individuelles : développement de nouvelles approches méthodologiques en oncologie prédictive et diagnostic prénatal." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS391/document.

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L’objectif principal de ce projet de recherche doctorale est la mise au point d’approches méthodologiques fiables et reproductibles permettant la caractérisation génétique de cellules rares circulantes isolées par la méthode de filtration ISET® (Rarecells®, France). La première application développée consiste en la détection des mutations du gène suppresseur de tumeur VHL (Von Hippel Lindau) dans les cellules rares circulantes (CRC) uniques isolées du sang de 30 patients atteints de carcinome rénal à cellules claires (CRCC), et réalisée comparativement à l’analyse cytopathologique. L’étude génétique a également été conduite en parallèle dans les 30 tissus tumoraux correspondants. Les résultats ont mis en lumière une potentielle complémentarité de l’approche de génétique moléculaire sur cellules uniques avec l’analyse cytomorphologique de référence et suggèrent que combiner ces approches permettrait d’obtenir une plus grande sensibilité de détection des cellules cancéreuses circulantes chez les patients atteints de CRCC. Une deuxième application a consisté en le développement d’une approche innovante pour le diagnostic prénatal non-invasif des maladies génétiques récessives par analyse de cellules trophoblastiques rares collectées au niveau du col de l’utérus. Enfin, des développements supplémentaires ont permis d’optimiser les analyses de séquençage à haut débit et de les appliquer à des CRC individuelles isolées par ISET®. Cette nouvelle approche, associée à l’isolement de CRC non fixées, est en mesure de fournir des données génétiques élargies à l’exome entier pour des applications à la fois en oncologie prédictive et en diagnostic prénatal non invasif
The aim of this doctoral research project is the development of reliable and reproducible methodological approaches enabling the genetic characterization of circulating rare cells (CRC) isolated by ISET® filtration (Rarecells®, France). The first application developed consists in detecting mutations of the VHL (Von Hippel Lindau) tumor suppressor gene in single CRC isolated from the blood of 30 patients patients with clear cell renal cell carcinoma (ccRCC), assessed according to the results obtained by cytopathological analysis. In parallel, genetic analysis of VHL mutations was conducted in the corresponding tumor tissues. Results revealed a potential complementarity of the molecular genetic approach targeted to single cells with the reference method of cytopathological analysis and suggested that combining both strategies could improve the sensitivity of circulating cancer cells’ detection in patients with ccRCC. A second application consisted in the development of an innovative approach for non-invasive prenatal diagnosis of recessive genetic diseases by analysis of rare trophoblastic cells collected from the cervix. Finally, further developments allowed to optimize high-throughput sequencing analyses and to apply them to single CRC isolated by ISET®. This approach, combined with the isolation of living CRC, enabled us to obtain broader genetic data from the whole exome and should foster innovative applications to both predictive oncology and non-invasive prenatal diagnosis
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15

Rees, Anne [Verfasser]. "Evaluation of udder firmness and fecal cortisol metabolites as cow-side parameters in dairy cows / Anne Rees." Berlin : Freie Universität Berlin, 2017. http://d-nb.info/1129174441/34.

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16

Mariet, Anne-Sophie. "Influence de l’exposition au bruit et à la pollution de l’air en milieu urbain sur la survenue de complications et d’issues défavorables de la grossesse." Thesis, Bourgogne Franche-Comté, 2020. https://nuxeo.u-bourgogne.fr/nuxeo/site/esupversions/b8bd098d-4e78-4f44-b87c-01a65906c7a1.

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La grossesse constitue une période de vulnérabilité où la survenue de complications et d’issues défavorables de la grossesse (CIDG) peut avoir des conséquences majeures sur le devenir de la mère et/ou du nouveau-né. De multiples facteurs en sont à l’origine. Cependant, il reste encore une part non expliquée de CIDG, pour laquelle l’environnement est suspecté de jouer un rôle.Ce travail de thèse est inclus dans le programme PreCEE (Pregnancy Combined Environmental Exposure) et a pour objectif d’étudier l’influence des expositions environnementales aux pollutions sonore et atmosphérique sur la survenue de CIDG, plus particulièrement de troubles de la croissance fœtale et de troubles hypertensifs de la grossesse. Ont été incluses toutes les grossesses de femmes majeures résidant à Besançon ou dans l’unité urbaine de Dijon et ayant accouché au CHU de Besançon ou au CHU Dijon-Bourgogne entre 2005 et 2009, soit plus de 10 000 grossesses. Les caractéristiques socio-démographiques, médicales et médico-obstétricales ont été recueillies à partir des dossiers obstétricaux informatisés et papier. Les niveaux d’exposition au bruit et à la pollution atmosphérique (dioxyde d’azote (NO2) et particules fines (PM10)) ont été modélisés au domicile de la mère selon des fenêtres spatiales et temporelles différentes.Les résultats montrent que l’exposition au bruit n’est pas associée à la survenue de troubles hypertensifs de la grossesse ou de troubles de la croissance foetale, chez les grossesses uniques. L’exposition aux PM10 est associée à la survenue de troubles de la croissance fœtale chez les grossesses uniques. Cette association n’est pas modifiée par la prise en compte de l’exposition au bruit. Enfin, chez les grossesses multiples, l’exposition au NO2 est associée à la survenue de troubles de la croissance fœtale
Pregnancy is a period of vulnerability where the occurrence of adverse pregnancy outcomes (APO) can have major consequences on the future of the mother and/or the newborn. Multiple factors are responsible for this. However, there is still an unexplained part of APO, for which the environment is suspected to play a role.This PhD thesis is included in the PreCEE (Pregnancy Combined Environmental Exposure) program and aimed to study the influence of environmental exposures to noise and air pollution on the occurrence of APO, more particularly on fetal growth disorders and hypertensive disorders of pregnancy (HDP). All pregnancies of adult women living in Besançon or in the urban unit of Dijon and who gave birth to the Besançon University Hospital or the Dijon-Burgundy University Hospital between 2005 and 2009 were included, i.e. more than 10,000 pregnancies. The socio-demographic, medical and medico-obstetrical characteristics were collected from computerized and paper obstetric records. The levels of exposure to noise and air pollution (nitrogen dioxide (NO2) and fine particles (PM10)) were modeled at the mother's home according to several spatial and temporal windows.Results show that noise exposure is not associated with the occurrence of HDP or fetal growth disorders in single pregnancies. Exposure to PM10 is associated with fetal growth disorders. This association is not changed by taking noise exposure into account. Finally, in multiple pregnancies, exposure to NO2 is associated with fetal growth disorders
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17

Hewitt, Damien Phillip. "Impact of glucocorticoids on placental growth and vascularisation." University of Western Australia. School of Anatomy and Human Biology, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0195.

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[Truncated abstract] Glucocorticoids are critical for the maturation of the fetus late in pregnancy. Indeed, clinical administration of glucocorticoids is used to accelerate fetal lung maturation in mothers at risk of pre-term delivery. Increased glucocorticoid exposure, however, can have detrimental effects on fetal and placental growth and increase the risk of disease in later life. Many studies have focused on the effect of an increase in the transplacental passage of glucocorticoids on both fetal growth and subsequent postnatal development. But there is a growing body of evidence to suggest that the impact of glucocorticoids on fetal growth is mediated, in part, via their direct effects on the placenta . . . Overall, these studies quantify the labyrinth zone-specific increases in placental expression of PPARG and VEGF in association with a marked increase in vascularisation observed near term. Furthermore, this study demonstrates for the first time that these increases in gene expression are prevented by maternal dexamethasone treatment which also inhibits growth of the fetal capillary network. Elevated expression of SFRP4 in the regressing basal zone late in gestation and in both placental zones after dexamethasone-induced placental growth restriction is consistent with a role for SFRP4 in glucocorticoid-mediated inhibition of wnt signalling. Collectively, the data presented in this thesis show that glucocorticoid inhibition of fetal growth is mediated in large part via effects on the placenta, specifically through inhibition of signals that promote proliferation and vascularisation.
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18

Cavallin, Mara. "Physiopathologie moléculaire et cellulaire des anomalies du développement du cortex cérébral : le syndrome d'Aicardi WDR81 mutations cause extreme microcephaly and impair mitotic progression in human fibroblasts and Drosophila neural stem cells TLE1, a key player in neurogenesis, a new candidate gene for autosomal recessive postnatal microcephaly Mutations in TBR1 gene leads to cortical malformations and intellectual disability Aicardi syndrome: Exome, genome and RNA-sequencing of a large cohort of 19 patients failed to detect the genetic cause Recurrent RTTN mutation leading to severe microcephaly, polymicrogyria and growth restriction Recurrent KIF2A mutations are responsible for classic lissencephaly Recurrent KIF5C mutation leading to frontal pachygyria without microcephaly Rare ACTG1 variants in fetal microlissencephaly De novo TUBB2B mutation causes fetal akinesia deformation sequence with microlissencephaly: An unusual presentation of tubulinopathy A novel recurrent LIS1 splice site mutation in classic lissencephaly Further refinement of COL4A1 and COL4A2 related cortical malformations Prenatal and postnatal presentations of corpus callosum agenesis with polymicrogyria caused By EGP5 mutation Delineating FOXG1 syndrome from congenital microcephaly to hyperkinetic encephalopathy Delineating FOXG1 syndrome: From congenital microcephaly to hyperkinetic encephalopathy." Thesis, Sorbonne Paris Cité, 2019. https://wo.app.u-paris.fr/cgi-bin/WebObjects/TheseWeb.woa/wa/show?t=2213&f=18201.

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Les malformations du cortex cérébral (MDC) représentent une cause importante de handicap et d'épilepsie pharmaco-résistante. Le séquençage à haut débit a permis une amélioration considérable de l'identification des bases moléculaires des MDC non syndromiques. Toutefois, certaines formes, notamment les MDC complexes, demeurent inexpliquées. Mon projet de thèse a pour objectif de progresser dans la compréhension des MDC complexes en utilisant deux modèles : les microlissencéphalies (MLIS) et le syndrome d'Aicardi (AIC), une forme syndromique particulière associant des malformations de l'oeil et du cerveau uniquement rapporté chez les filles. L'étude par séquençage d'exome en trios de 16 familles MLIS m'a permis d'identifier et de caractériser un nouveau gène, WDR81, impliqué dans le cycle cellulaire. Par la même stratégie, j'ai pu identifier un variant homozygote pathogène dans TLE1, un partenaire majeur de FOXG1 dans la balance prolifération/différenciation de progéniteurs neuronaux, dans une famille consanguine de microcéphalie postnatale dont le phénotype est proche du syndrome FOXG1. En parallèle, mes travaux ont permis de préciser les spectres phénotypiques associés à RTTN, EPG5, COL4A1, COL4A2, TBR1, KIF5C, KIF2A et FOXG1. La deuxième partie de mon projet avait pour objet l'identification des bases moléculaires du syndrome d'Aicardi à partir d'une cohorte internationale de 19 patientes. Après avoir exclu un biais d'inactivation du chromosome X et la présence de microremaniements chromosomiques, j'ai réalisé un séquençage d'exome en trio. Aucun variant récurrent n'a été retrouvé dans les séquences codantes. Dans un second temps, j'ai testé une approche combinant les données du séquençage de génome et l'analyse du transcriptome (RNA-Seq) sur fibroblastes, me permettant d'identifier des transcrits dérégulés qui étaient impliqués dans le développement du cerveau et de l'oeil. J'ai comparé les résultats de cette analyse avec ceux de l'analyse du génome dans le but d'identifier des variants dans ces gènes candidats. En conclusion, mon travail de thèse a permis d'améliorer la connaissance des bases moléculaires des MDC complexes et d'ouvrir des perspectives de nouveaux mécanismes tels que ceux engageant les gènes WDR81 et EPG5, et le rôle des endosomes et de l'autophagie dans les MDC, et aussi TLE1 comme nouvelle cause de microcéphalies postnatales. Mes travaux ont également permis de générer une collection de données de séquençage haut débit (WES, WGS et RNA-Seq) qui seront mises en commun dans le cadre d'un consortium international afin de développer des nouvelles stratégies d'analyse en particulier pour les séquences non codantes. Cette approche permettra également d'ouvrir la voie vers la compréhension des mécanismes cellulaires impliqués dans la formation du cerveau et de l' œil
Malformations of cortical development (MCD) are a major cause of intellectual disability and drug-resistant epilepsy. Next Generation Sequencing (NGS) has considerably improved the identification of the molecular basis of non-syndromic MCD. However, certain forms, including complex MCD, remain unexplained. My PhD project aimed to improve the understanding of complex MCD using two disorders: Microlissencephaly (MLIS) and Aicardi Syndrome (AIC), the latter associating brain and eye malformations and only reported in girls. Trio Whole Exome Sequencing (WES) performed in 16 MLIS families allowed me to identify and functionally characterize a new MLIS gene, WDR81, in which mutations lead to cell cycle alteration. Moreover, using the same strategy, I was able to identify a pathogenic homozygous variant in TLE1 in a patient from consanguineous family with a postnatal microcephaly, suggestive of a FOXG1-like presentation. Interestingly, TLE1 is a major partner of FOXG1, a gene involved in maintaining the balance between progenitor proliferation and differentiation. In parallel, my work allowed me to redefine the phenotypic spectrum associated with RTTN, EPG5, COL4A1 and COL4A2, TBR1, KIF5C, KIF2A and FOXG1. The second part of my PhD program was aimed at identifying the genetic basis of AIC in an international cohort of 19 patients. After excluding a skewed X chromosome inactivation and the presence of chromosomal rearrangements, I performed WES in trios. The analysis of the data from WES did not allow me to identify any recurrent variants. I therefore tested a new approach combining Whole Genome Sequencing (WGS) and RNA-Sequencing (RNA-Seq) on fibroblast cells. I identified a number of deregulated transcripts implicated in brain and eye development. I compared the results of this analysis with the WGS analysis in order to find variants in these candidate genes. In conclusion, these studies have improved the knowledge of the molecular basis of complex MCD, such as TLE1 in postnatal microcephaly, and revealed the pathogenic mechanisms such as WDR81 in cell cycle progression and EPG5 in endosomes and autophagy. My work has also generated a collection of NGS data (WES, WGS and RNA-Seq) that will be shared in an international consortium to develop new analytical strategies, in particular for the non-coding DNA regions. This novel strategy provides opportunities to improve understanding of the cellular mechanisms involved in brain and eye development
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19

"Body size relationships and reproductive ecology of female feral horses on Sable Island, Nova Scotia." Thesis, 2015. http://hdl.handle.net/10388/ETD-2015-03-1977.

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Body size is an important determinant of reproduction in capital breeding animals, including large mammals. However, it is not always practical to hand-measure body size of free-ranging species. In recent years, parallel-laser photogrammetry has been used to obtain remote estimates of body size for some animals, though it remains unknown how well this technique might capture variation in curvilinear body features or if the distance between parallel-laser calipers is altered when projected onto a curved surface. In this thesis, I describe a photogrammetric system that may be useful for obtaining body-size measurements from unrestrained large mammals that permit approach, using domestic horses (Equus ferus caballus) as a model (Chapter 2). I then apply this technique in the field to a wild (feral) population of horses at Sable Island National Park Reserve, Nova Scotia, Canada, where I include body size measurements as variables in a detailed analysis of factors affecting reproduction in females (Chapter 3). Using my parallel-laser photogrammetric system, I show how curvilinear hand-measurements (e.g., across the barrel of a horse) are stongly correlated with their respective linear photogrammetric estimates (R2 ≥ 0.998), and most photogrammetric estimates using my system had high reliability. Using three variables of body size, photogrammetric estimates and hand-measurements explained 86.0% and 96.2%, respectively, of the variation in body weight of a sample of domestic Newfoundland ponies. On Sable Island, Nova Scotia, I examined the relationship of numerous variables (including skeletal body size and body condition) with the probability of yearly reproductive success for female Sable Island horses (years 2008–2012), where I define reproductive success as production of an offspring surviving to one year of age. Age class was a dominant factor predicting reproductive success, as expected from trends previously associated with body size or reproductive experience iii in other populations. Age-class specific energy budgets or social and sexual behaviour caused a more pronounced relationship with body condition at parturition in sub-adults, and body condition at conception and stability of consort relationships were associated with reproductive success in adults. In addition, relationships with local density suggested limited forage around the time of conception and limited water during lactation might also influence reproductive success in adult females. Although relationships were evident for age class, which is correlated with body size, reproductive success was not related to skeletal body size, past reproductive experience, age of primiparity, or band structure. The capital breeding strategy and year-round social associations seen in horses make their reproductive ecology a combination of patterns observed for large ungulates and social primates.
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Wu, Wan-Ru, and 吳婉如. "The Effectiveness of Internet Social Networking Site on Pregnancy Women’s Psycho-Physical Symptoms, depression, Social Support, Maternal Fetal Attachment and Pregnancy Adaptation." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/3u4x8g.

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博士
高雄醫學大學
護理學系博士班
104
The purpose of study is to examine the effectiveness of an Internet social networking site for Taiwanese pregnant mother on their psycho-physical symptoms, depression, social support, maternal fetal attachment, and prenatal adaptation. The study is originally designed from the perspective of intergrating low rates of Taiwan total fertility, the loss of traditional family support network, and the convenience of internet. Stress theory is used as the study framework, and a closed online social networking site is provided for experimental group as intervention. Participants was recruited at a medical-center leveled hospital in southern Taiwan. Fifty-five pregnant women in compare group receives ordinary prenatal care. Sixty-six pregnant women in experiment group receives ordinary prenatal care and are invited to join the internet social networking site to sharing pregnancy related experience with other peer members. Baseline data is collected in the first-trimester, and post measurements are in the second and the third trimester. Instruments including prenatal psycho-physical symptoms, Edinburgh depression scale, social support scale, maternal fetal attachment, and prenatal adaptation questionnaire are used in the study. Generalized Estimating Equations (GEE) is used to analyze the differences between two groups. The study results indicate no significant differences on prenatal psycho-physical symptoms, depression, social support, maternal fetal attachment, and pregnancy adaptation between two groups. More health-related online support studies is needed for developing future knowledge.
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21

Cruz, André de Santa Bárbara Beirão da. "Show me your best side : lateralization of social behaviours on a population of feral horses - a case study." Master's thesis, 2021. http://hdl.handle.net/10400.12/8129.

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Thesis presented at ISPA – Instituto Universitário as to obtain a Master’s degree in the specialty of Cognitive and Behavioural Neuroscience
Recent evidence in the animal kingdom, specifically in the Phylum Chordata, has revealed a variety of asymmetries regarding social and non-social behaviours. These preferences for side use can be translated into a lateralized processing of information in the brain. Studies performed with domestic horses show several behavioural asymmetries, however, domestic horses have a lot of interaction with caretakers and tend to lack real threats. This study investigated lateralization in frequency and duration of social interactions (affiliative and agonistic) and in resting behaviours on feral horses (Equus ferus caballus). While a small skewness of the data for a left-side preference was found for agonistic behaviours, statistical analyses revealed no significant bias. Horses were more prone to display grooming interactions using the right side and this behaviour lasted longer on this side, but no bias was found for cross-resting (although a skewness was visible for the left side). As for resting, although no bias was found for frequency of side use, a marginal (albeit non-significant) difference was present for the duration, resting tends to last longer when performed on the left side. These results do not entirely support a right-hemisphere dominance for social interactions nor a valence-specific assumption (left-hemisphere dominance for positive affect and right-hemisphere dominance for negative affect). Our findings on the right-side bias for grooming may eventually be interpreted as a role of the environment (ecological pressures) that shapes lateralization in different behaviours.
Novas evidências no Reino Animal, em específico no Filo Chordata, mostram frequências diferentes na direção de comportamentos sociais e não sociais. A propensão pelo uso de um lado revela um processamento de informação lateralizado no encéfalo. Estudos com cavalos domésticos revelam assimetrias comportamentais, porém, cavalos domésticos podem estar sujeitos a treino, para além de uma ausência de perigos como predação. Este estudo investiga a lateralização em cavalos assilvestrados (Equus ferus caballus) na frequência e duração de comportamentos sociais (afiliativos e agonísticos) e no comportamento de repouso. A tendência para o uso do lado esquerdo em comportamentos agonísticos não revelou nenhum enviesamento significativo. Contudo, uma preferência estatisticamente significativa pelo uso do lado direito foi encontrada para o comportamento de grooming e a duração do mesmo era maior com o uso desse lado. O comportamento de repouso cruzado não apresentou diferenças significativas a nível da frequência ou duração, todavia apesar do repouso não ter exibido diferença na frequência, a duração aparenta (apesar de não significativamente) ser mais longa com o uso do lado esquerdo. Estes resultados não apoiam inteiramente a hipótese de um controlo do hemisfério direito para comportamentos sociais nem são inteiramente congruentes com a ideia de especificidade de valência (dominância do hemisfério esquerdo para comportamentos com valência positiva e do hemisfério direito para comportamentos com valência negativa). Contudo, a lateralização para o lado direito no grooming poderá vir a ser interpretada como o resultado de pressões seletivas que moldam a lateralização de diferentes comportamentos.
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22

Rademacher, Thomas. "Untersuchung atomarer Strukturen an geordnetem und nanokristallinem ternären Fe3Al." Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-B52F-3.

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23

(9809528), Benjamin Kele. "On-site wastewater treatment and reuse using recirculatory evapotranspiration channels in regional Queensland." Thesis, 2005. https://figshare.com/articles/thesis/On-site_wastewater_treatment_and_reuse_using_recirculatory_evapotranspiration_channels_in_regional_Queensland/13423052.

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Abstract:
"The Central Queensland University developed an on-site wastewater treatment and reuse technology. Septic tanks were used for primary treatment and the discharged effluent was then pumped though a series of contained channels. The channels were designed to be a modified evapotranspiration trench; they were comprised of an aggregate layer and a soil layer in which were planted a variety of plants. The aggregate and the soil provided physical filtration, the microorganisms within the effluent, aggregate and soil provided nutrient reuse and transformation and the plants also used the nutrients and reused the treated effluent through evapotranspiration. Any effluent that was not transpired was returned to a holding tank and pumped through the evapotranspiration again. The treatment technology was assessed in relation to its ability to treat effluent in a sustainable manner. The water and soil was examined for concentrations of nutrients, heavy metals, salts, sodium, and organic carbon %. The pH, temperature and number of colony forming units of certain microorganism potential pathogens were also inspected in the soil and the water. The plants grown within the evapotranspiration channels were assessed in regards to their health, water usage, and in some cases potential pathogens on fruit. The infrastructure that was used to construct the wastewater treatment and reuse system was also evaluated in regards to reliability and maintenance. Certain limiting factors, in particular sodicity and salinity were identified, but the trial was successful and a sustainable form of on-site wastewater treatment and reuse technology was developed." --abstract

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24

Pestana, Marco António Correia. "O lugar da obra : uma investigação sobre arte e natureza." Master's thesis, 2022. http://hdl.handle.net/10451/51076.

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This investigation theoretically addresses the artist's concerns in action and presence in the places he travels in close proximity to the natural and rural environment. Through this research, I tried to find the reasons for the ways of living the places that emerged during the research and that are recurrent nowadays, namely, immobility, inaction, distraction, and their beneficial consequences. This dissertation addresses issues related to ecology, individual behaviour in the connection with the natural environment and existential issues related to the artist's inaction. One of the challenges of this investigation was to understand which forms or methods of creation that allowed me the relationship between creation and experience, that is, being in a place, in contemplation, experiencing everything that involves me, what are the ways that allowed me to create without jeopardizing the experience. It is in response to this challenge that photography appears, being one of the ways to capture and record images with which I felt most comfortable.
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