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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Structure and Function of the Retina in Children Born Extremely Preterm and in Children Born At Term

Molnar, Anna January 2017 (has links)
Background: Optical coherence tomography (OCT), multifocal electroretinography (mfERG) and full-field electroretinography (ffERG) give important information about retinal structure and function. Purpose: To collect normative data of macular Cirrus Spectral domain (SD)-OCT assessments and of mfERG measurements of healthy children (papers I and II). To assess the macular thickness with Cirrus SD-OCT and the retinal function with ffERG in 6.5-year-old children born extremely preterm and in children born at term (papers III and IV). Methods: Study participants aged 5-15 years and living in Uppsala County were randomly chosen from the Swedish Birth Register (papers I and II). In papers III and IV, the study participants consisted of children born extremely preterm and children born at term – all were aged 6.5 years. In paper III, the children were living in Stockholm and Uppsala health care regions and, in paper IV, in Uppsala health care region only. Macular thickness was assessed with Cirrus SD-OCT and macular function with mfERG, using the Espion Multifocal system and DTL-electrodes. The retinal function was assessed with ffERG and DTL-electrodes, using the Espion Ganzfield system. Results: Altogether, 58 children participated in paper I and 49 children in paper II. In paper I, the repeatability and reproducibility of the OCT assessments were good. In paper II, the results of the mfERG measurements were in accordance with retinal cone density and there were no significant differences between the right and left eyes. In paper III, 134 preterm children and 145 children born at term constituted the study population. The central macular thickness was significantly thicker in the preterm group than in the control group. Within the preterm group, gestational age (GA), former retinopathy of prematurity (ROP) and male gender were all important risk factors for an increased macular thickness. In paper IV, 52 preterm children and 45 control children constituted the study population. Significantly lower amplitudes and prolonged implicit times of the combined rod and cone responses, as well as of the isolated cone responses, were found in the preterm group when compared with the control group. In paper IV, there was no association between GA, ROP or male gender and the ffERG assessments. Conclusion: Normative data of Cirrus SD-OCT and mfERG assessments were reported. The results of the assessments were reliable. Children aged 6.5 years, born extremely preterm, had a significantly thicker central macula and both rod and cone function were significantly reduced in comparison to children born at term. ROP had an influence on retinal structure but not retinal function in the present cohorts. Our results suggest that retinal development is abnormal in children born extremely preterm. Long-term follow-up studies are necessary in order to evaluate the functional ophthalmological outcome in this vulnerable population of children growing up today.
32

Development of the fast steering secondary mirror assembly of GMT

Lee, Sungho, Cho, Myung K., Park, Chan, Han, Jeong-Yeol, Jeong, Ueejeong, Yoon, Yang-noh, Song, Je Heon, Park, Byeong-Gon, Dribusch, Christoph, Park, Won Hyun, Jun, Youra, Yang, Ho-Soon, Moon, Il-Kwon, Oh, Chang Jin, Kim, Ho-Sang, Lee, Kyoung-Don, Bernier, Robert, Alongi, Chris, Rakich, Andrew, Gardner, Paul, Dettmann, Lee, Rosenthal, Wylie 22 July 2016 (has links)
The Giant Magellan Telescope (GMT) will be featured with two Gregorian secondary mirrors, an adaptive secondary mirror (ASM) and a fast-steering secondary mirror (FSM). The FSM has an effective diameter of 3.2 m and built as seven 1.1 m diameter circular segments, which are conjugated 1:1 to the seven 8.4m segments of the primary. Each FSM segment contains a tip-tilt capability for fine co-alignment of the telescope subapertures and fast guiding to attenuate telescope wind shake and mount control jitter. This tip-tilt capability thus enhances performance of the telescope in the seeing limited observation mode. As the first stage of the FSM development, Phase 0 study was conducted to develop a program plan detailing the design and manufacturing process for the seven FSM segments. The FSM development plan has been matured through an internal review by the GMTO-KASI team in May 2016 and fully assessed by an external review in June 2016. In this paper, we present the technical aspects of the FSM development plan.
33

Analyse de front d'onde sur étoile laser allongée pour l'optique adaptative de l'ELT / Elongated laser guide star wavefront sensing for the ELT adaptive optics systems

Bardou, Lisa 27 September 2018 (has links)
L’ELT (Extremely Large Telescope), est un télescope de diamètre 39 m en cours de réalisation par l’Observatoire Européen Austral (ESO). Pour pouvoir tirer pleinement parti de sa taille, ses instruments seront équipés de systèmes d’Optique Adaptative (OA) qui compenseront la turbulence atmosphérique. Ces systèmes d’OA requièrent l’utilisation d’étoiles guides laser afin de maximiser la couverture du ciel. Les étoiles guides laser sont générées par laser accordé sur une résonance d’atome de sodium présents dans une couche d’une épaisseur de 10 km et située à environ 90 km d’altitude. Une étoile laser est donc un cylindre lumineux dans la haute atmosphère, allumé par la relaxation des atomes. L’analyse de front d’onde à l’aide de ces étoiles artificielles souffrent de limitations connues. De plus, sur un télescope de la taille de l’ELT, leur utilisation est compliquée par l’effet de perspective qui provoque un allongement de l’étoile guide lorsqu’elle est vue d’un point éloigné de son point de lancement au sol : le cylindre n’est plus vu par une section circulaire, mais sur le côté. Sur un télescope de 39m, l’élongation de l’étoile peut alors atteindre jusqu’à 20 secondes d’arc, à comparer avec le diamètre du cylindre qui est déterminé par la turbulence, soit de l’ordre d’une seconde d’arc. La variabilité de l’épaisseur, de l’altitude et de la distribution de densité de la couche de sodium ont alors un impact sur la mesure du front d’onde.L’étude de ce problème, qui porte à la fois sur les algorithmes de mesure et le design des analyseurs de front d’onde, a donné lieu à de nombreux travaux s’appuyant sur des simulations et des tests en laboratoire. Le but de cette thèse a été d’étudier cette question à l’aide de données expérimentales obtenues sur le ciel. Ces données ont été enregistrées grâce au démonstrateur d’OA CANARY, situé sur le télescope William Herschel sur l’île de la Palma aux Canaries. CANARY a été développé par le LESIA, en collaboration avec l’Université de Durham; le laser et son télescope d’émission ont été fournis et opéré par l’ESO. Lors de cette expérience, l'allongement extrême des étoiles laser qui sera observé sur l'ELT a été reproduit en plaçant le télescope d’émission à environ 40m du télescope William Herschel. Le front d'onde a ensuite été mesuré sur l’étoile laser allongée ainsi crée.Les travaux effectués pendant cette thèse ont consisté en la préparation de l’instrument et en particulier de l’analyseur de front d’onde de l’étoile laser, la réalisation des observations et le traitement des données résultant de ces dernières. L’analyse de ces données a permis de construire un budget d’erreur de la mesure de front d’onde sur étoile laser allongée. Grâce à ce budget d’erreur, les performances de différents algorithmes de mesure ont été comparées, ainsi que leur comportement face à la variabilité du profil de sodium et des conditions de turbulence. Enfin, différentes configurations d’analyseurs ont été extrapolées, ce qui a permis d’établir des limites sur leur design dans le cadre de l’ELT. / The ELT (Extremely Large Telescope) is a telescope whose diameter is 39 m currently under construction by the European Southern Observatory (ESO). In order to fully benefit from its size, ELT instruments will be equipped with Adaptive Optics (AO) systems to compensate the atmospheric turbulence. These AO systems require the use of Laser Guides Stars (LGS) in order to have as large a sky coverage as possible. LGS are generated using a laser tuned on a resonant frequency of sodium atoms contained in a layer approximately 90km high and 10 km thick. Therefore, a LGS is a luminous cylinder in the high atmosphere, lighted by sodium atoms relaxation. Wavefront sensing on these artificial stars suffers from known limitations. On a telescope the size of the ELT, their use is further complicated by the perspective effect which causes an elongation of the LGS when it is seen from a point distant from its launch position : the cylinder is no longer seen by its circular section, but on the side. On a 39m telescope, the elongation can reach up to 20 arcseconds, which is large compared to to the diameter of the cylinder determined by the turbulence, that is about 1 arcsecond. Variability of the thickness, height and density distribution of the sodium layer then have an impact on wavefront sensing. The study of this problem, which concerns both sensing algorithms and wavefront sensor design, has already been the subject of many work relying on simulations and laboratory experiments. This thesis aims at studying this question using experimental data obtained on sky. These data were acquired using the AO demonstrator CANARY, placed on the William Herschel Telescope (WHT) on the island of La Palma in the Canaries Island. CANARY was developed by LESIA in collaboration with Durham University; the laser and its launch telescope were supplied and operated by ESO. In this experiment, the extreme elongation of LGS as will be seen on the ELT was reproduced by placing the launch telescope 40 m away from the William Herschel Telescope. The wavefront was the measured on the elongated LGS thus created. The studies led during this thesis consisted in the preparation of the instrument and in particular the LGS Wavefront Sensor (WFS), the realisation of the observations and processing on the data obtained. Analysis of these data allowed to build an error breakdown of wavefront sensing on the elongated LGS. Thanks to this error breakdown, performances of different measurement algorithms where compared, as well as their behaviour according to the variability of the sodium profile and the turbulence conditions. Finally, different wavefront sensor designs were extrapolated which allowed to establish limits on their designs for the ELT.
34

I’m OK”: Levels of Communication and Trauma Recovery in Jonathan Safran Foer’s Extremely Loud and Incredibly Close

Shlomo Gross, Mihaela January 2014 (has links)
Jonathan Safran Foer’s novel Extremely Loud and Incredibly Close stands out from the nationalistic-toned American “9/11 novels”. It depicts the story of a young boy and his grandparents who are left with the aftermath of losing a loved one in the attack on the twin towers. However, the complexity of the three main characters and the depth of their individual and common traumas make the novel go beyond the usual nationalistic 9/11 narrative and focus on the personal and, consequently, the national trauma.  This essay analyses the possibility of coping with and recovering from trauma through communication. Dominick LaCapra’s trauma theory notions of “working through” and “acting out”, as well as other traumatic memory research highlight the necessity of utterance in order to overcome trauma and to attempt an existence beyond it. In the instance of the three traumatized characters of the novel, the confessional language is entangled, broken and sometimes muted. This makes the recovery difficult in the case of the grandparents, almost impossible for the character of Grandpa. When it comes to the young boy, Oskar Schell, a more successful communication seems to open up the possibility of mental healing. These personal traumas are a reflection of a broader American trauma where an obsessive “rememoration” of the September 11 events and one-sided, revenge loaded public discourse do not seem to facilitate the national healing process. On all these levels, personal and community, the need and the difficult attempt to communicate the trauma of 9/11 does not necessarily grant recovery from it, but it facilitates a desired “working though” process.
35

KULINARIJOS PRADMENŲ PROGRAMOS SPECIALIŲJŲ UGDYMOSI POREIKIŲ MOKINIAMS PLĖTOTĖ / DEVELOPMENT OF COOKERY BASICS PROGRAM FOR CHILDREN WITH SPECIAL EDUCATIONAL NEEDS

Kasputytė, Ingrida 27 August 2009 (has links)
Darbe atlikta teorinė ugdymo turinio individualizavimo samprata, nurodyti individualios programos rengimo principai ir etapai. Iškelta hipotezė, kad ugdydami vidutinius ir didelius specialiuosius ugdymosi poreikius patiriančius mokinius, mokytojai moko tų pačių temų, tik nustato skirtingą jų įsisavinimo laiką ir skirtingus mokymo būdus, o rengdami individualias kulinarijos pradmenų ugdymo programas vidutinius ir didelius specialiuosius ugdymosi poreikius patiriantiems mokiniams mokytojai derina bendrąsias ir specialiąsias programas. Anketinės apklausos metodu bei mokyklos dokumentų analize buvo atliktas tyrimas, kurio tikslas- ištirti ko ir kaip pedagogai moko aukštesniųjų lavinamųjų klasių mokinius ugdydami jų kulianrijos pradmenų gebėjimus. Parengtos rekomendacinės kulinarijos pradmenų ugdymo temos vidutinius ir didelius specialiuosius ugdymosi poreikius patiriantiems mokiniams, pravestas eksperimentinis mokymas, įvertinti ir palyginti mokinių gebėjimai gaminti valgį iki eksperimentinio mokymo ir po jo. Siekiama nustatyti, kokiais kriterijais remdamiesi mokytojai nustato, kokiu lygiu mokiniai įsisavino programą. Tyrime dalyvavo 30 specialiosios mokyklos aukštesniųjų lavinamųjų klasių mokinių technologijų mokytojų ir 60 5 - 10 lavinamųjų klasių mokinių. Empirinėje dalyje nagrinėjamas mokytojų suvokimas apie lavinamųjų klasių mokinių gebėjimą gaminti valgį, nustatomi trys mokinių gebėjimų lygiai: gebančių savarankiškai gaminti, gebančių gaminti su pagalba ir negebančių... [toliau žr. visą tekstą] / Development of cookery basics should help those children to accomplish the objective to be grown-ups, independent and able to take care of themselves. Schoolchildren, having acquired food preparation skills will have a greater freedom of choice and more possibilities to live a more independent life. Hypothesis: it is likely that poor cooking skills impede children independent functioning in social environment, therefore suggested topics for development of cookery program will satisfy the needs of children with extensive and extremely extensive educational needs and will benefit solution of this problem. 30 crafts teachers of upper grades of specialized school and 60 schoolchildren of extensive and extremely extensive special educational needs of upper grades (5-10) from specialized schools participated in the research. The most significant conclusions of empirical research: ● Data from teachers’ questionnaires reveal that all of them follow the program of “Cookery basics” and examine all of the recommended topics, least of their attention dedicating to the topics, such as “Essence of diet” and “Menu”. According to respondents, these topics do not meet children needs with extensive and extremely extensive special educational needs as well as possibilities to acquire them. ● Only fifth of participants are able to cook independently, about two fifths cook with the supervision of a teacher and two fifths do not prepare food at all. This confirms our hypothesis that poor... [to full text]
36

Význam IGF-I a vybraných polymorfismů v IGF1 genu pro postnatální růst dětí SGA/IUGR a extrémně nezralých novorozenců. / The impact of IGF1 and selected IGF1 gene polymorphisms on postnatal growth in children SGA/IUGR and extremely preterm newborns.

Kytnarová, Jitka January 2016 (has links)
Long-term outcome of extremely preterm neonates depends on many endogenous and exogenous factors. Long-term follow-up of extremely preterm neonates during childhood and analyses of IGF1 gene polymorphisms may help to better understand the problems connected with delayed postnatal growth and the progression of cardiovascular diseases and diabetes mellitus type 2 in adulthood. The aim was the long-term follow-up of anthropometric parameters in children born at 22−25th and 26−27th week of gestation and to study the association between postnatal growth of extremely preterm children, children small for gestational age (SGA) and children born at term with appropriate birth weight/length (AGA) and IGF1 gene polymorphisms: (CA)10-24 repetitive polymorphism in promoter, microsatellite marker D12S318 and 185 bp in 3'UTR, (CT)n polymorphism (CA)n polymorphism 216 bp in the intron 2. Methods. 242 infants born at 22-27+6 weeks were enrolled. Anthropometric parameters were measured at the ages of 2 and 5 years in 72 children born at 22-25+6 week (group I) and 85 children born at 26-27+6 week (group II). Polymorphisms of IGF1 were analysed in 51 extremely preterm, 208 AGA and 59 SGA children using fragment analyses. The data of postnatal growth data in AGA children were obtained at 18 months, in SGA and extremely...
37

Caesarean Section : Short- and long-term maternal complications

Hesselman, Susanne January 2017 (has links)
Caesarean section is a common major surgical procedure and long-term complications have not been fully investigated. By longitudinal population based register studies, based on National health registers and medical data records, maternal complications after caesarean delivery at subsequent labour (N=7 683), among extremely preterm births (N=406), and at remote gynaecologic surgery (N=25 354) were explored. In Paper I, uterine closure was investigated in respect to uterine rupture in a subsequent delivery after caesarean section. Uterine rupture occurred in 1.3 % of women with a previous caesarean section. There was no increased risk of uterine rupture with single compared with double layers for closure of the uterus (adjusted Odds Ratio 1.17, 95 % CI 0.78-1.70). Modifiable risk factors of uterine rupture in a trial of labour after caesarean section included induction of labour and use of epidural analgesia. In Paper II, maternal outcomes and surgical aspects of caesarean section in the extremely preterm period were assessed. Maternal complications were more frequently reported in extremely preterm- compared with term caesarean delivery. No increase in short-term morbidity was observed at 22-24 compared with 25-27 gestational weeks, but uterine corporal incisions were performed more frequently (18.1 % vs. 9.6 %, p=0.02). Furthermore, risk factors for abdominal adhesions after caesarean section and organ injury in remote gynaecologic surgery were analysed (Paper III and IV). Numbers of prior caesarean sections were the most important factor for formation of adhesions. Advanced maternal age, obesity, infection and delivery year 1997-2013 were factors associated with adhesions in conjunction with caesarean section. Organ injury occurred in 2.2 % of women undergoing benign hysterectomy. A history of caesarean section increased the risk (adjusted Odds Ratio 1.74, 95 % CI 1.41-2.15), but was only partly explained by the presence of adhesions. The organ affected depended on medical history; prior caesarean predisposed for bladder injury, prior bowel/pelvic surgery for bowel injury and endometriosis was associated with ureter injury at time of hysterectomy. In conclusion; data from National health registers indicates that caesarean delivery is associated with long-term complications, although the absolute risk of severe complications for the woman is low.
38

Význam IGF-I a vybraných polymorfismů v IGF1 genu pro postnatální růst dětí SGA/IUGR a extrémně nezralých novorozenců. / The impact of IGF1 and selected IGF1 gene polymorphisms on postnatal growth in children SGA/IUGR and extremely preterm newborns.

Kytnarová, Jitka January 2016 (has links)
Long-term outcome of extremely preterm neonates depends on many endogenous and exogenous factors. Long-term follow-up of extremely preterm neonates during childhood and analyses of IGF1 gene polymorphisms may help to better understand the problems connected with delayed postnatal growth and the progression of cardiovascular diseases and diabetes mellitus type 2 in adulthood. The aim was the long-term follow-up of anthropometric parameters in children born at 22−25th and 26−27th week of gestation and to study the association between postnatal growth of extremely preterm children, children small for gestational age (SGA) and children born at term with appropriate birth weight/length (AGA) and IGF1 gene polymorphisms: (CA)10-24 repetitive polymorphism in promoter, microsatellite marker D12S318 and 185 bp in 3'UTR, (CT)n polymorphism (CA)n polymorphism 216 bp in the intron 2. Methods. 242 infants born at 22-27+6 weeks were enrolled. Anthropometric parameters were measured at the ages of 2 and 5 years in 72 children born at 22-25+6 week (group I) and 85 children born at 26-27+6 week (group II). Polymorphisms of IGF1 were analysed in 51 extremely preterm, 208 AGA and 59 SGA children using fragment analyses. The data of postnatal growth data in AGA children were obtained at 18 months, in SGA and extremely...
39

Resuscitace a stabilizace extrémně nezralých novorozenců. / Stabilisation and resuscitation of extremely preterm newborns at birth.

Lamberská, Tereza January 2019 (has links)
Stabilisation and resuscitation in the delivery room is an integral part of the care of extremely premature newborns. The main task is to support essential life functions and to facilitate the adaptation of the immature organism to the extrauterine life. The current recommendations are well defined for the full term and late preterm newborns, but there is a lack of targeted recommendations for the stabilisation and resuscitation of extremely premature newborns. The research part of the submitted thesis summarises the most important results of clinical research performed in 2010-2015 at the Department of Neonatology of the Department of Gynecology and Obstetrics, VFN and First Faculty of Medicine, Charles University in Prague. The research evaluates the efficacy and side effects of the currently recommended methods of stabilisation and resuscitation of extremely premature neonates in the delivery room and presents some new and potentially useful techniques for delivery room care. A significant output of this work is the recommendation for practice, structured according to the gestational age of extremely premature newborns. The proposed guideline is based on our results of partial clinical trials and aims to improve the current level of stabilisation and resuscitation of extremely premature newborns...
40

The Influence of Childhood Cognitive Abilities on Adult Health and Socioeconomic Outcomes in Extremely Low Birth Weight Survivors / Childhood Cognition & Adult Outcomes of ELBW Survivors

Dobson, Kathleen January 2016 (has links)
Objectives: The purpose of this thesis is to explore the associations between childhood cognitive abilities assessed at age 8 and health and socioeconomic outcomes at age 29-36 in extremely low birth weight survivors (ELBW, <1000g). Methods: Using data from the McMaster Extremely Low Birth Weight Cohort Study, Study 1 explores the influence of overall intelligence, fluid intelligence, and language abilities on the prevalence of lifetime major depressive disorder in ELBW survivors and normal birth weight comparison subjects. Study 2 examines the mediating role of overall intelligence, fluid intelligence, language abilities, quantitative reasoning, and academic achievement on the association between being born at ELBW and socioeconomic outcomes at age 29-36. The final study examines the moderating role of childhood cognitive functioning on links between postnatal psychosocial adversity and adult personal earnings in ELBW survivors. Results: Results from Study 1 suggest that childhood cognitive abilities do not influence the onset of major depressive disorder in ELBW survivors, but are protective against depression in normal birth weight individuals. Study 2 suggests that childhood cognitive abilities partially mediate the association between being born at ELBW and income attainment in adulthood, but not full time employment. Further, Study 2 suggests that this association is stronger in ELBW survivors who have neurosensory impairments. Results of Study 3 suggest that enhanced childhood cognitive functioning is not protective against postnatal psychological adversity in influencing income attainment, as those ELBW survivors with higher childhood intelligence and who suffered psychological adversity reported lower annual income at age 30. Conclusions: This thesis suggests that overall and specific cognitive abilities significantly influence adult outcomes in ELBW survivors and normal birth weight individuals. However, while cognitive reserve may not be protective against psychological adversity in ELBW survivors, early cognitive abilities are a critical indicator of socioeconomic attainment in this vulnerable population. / Thesis / Master of Science (MSc) / The following thesis explores the predictive role of childhood cognitive abilities on adult health and socioeconomic outcomes in extremely low birth weight survivors at age 29-36. Study 1 explores the influence of overall intelligence, fluid intelligence, and language abilities assessed at age 8 on the prevalence of lifetime major depressive disorder in extremely low birth weight survivors and normal birth weight comparison participants. Study 2 examines the mediating role of overall intelligence, fluid intelligence, language abilities, quantitative reasoning, and academic achievement on the association between being born at extremely low birth weight and socioeconomic outcomes at age 29-36. The final study examines the moderating role of childhood cognition on the association between postnatal psychosocial adversity and personal income attainment at age 30 in extremely low birth weight survivors. Overall, this body of work suggests that childhood cognitive abilities are an important contributor to adult outcomes in preterm survivors.

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