Thèses sur le sujet « Longitudinal function »

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1

Pahwa, Punam. « Statistical modelling of longitudinal lung function data ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0035/NQ63908.pdf.

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2

Ekblom, Anna Gerber, Lars B. Dahlin, Hans-Eric Rosberg, Monica Wiig, Michael Werner et Marianne Arner. « Hand function in children with radial longitudinal deficiency ». Uppsala universitet, Handkirurgi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-199846.

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BACKGROUND: In children with hypoplasia or aplasia of the radius (radial longitudinal deficiency) manual activity limitations may be caused by several factors; a short and bowed forearm, radial deviation of the wrist, a non-functional or absent thumb, limited range of motion in the fingers and impaired grip strength. The present study investigates the relation between these variables and activity and participation in children with radial dysplasia. METHODS: Twenty children, age 4-17 years, with radial longitudinal dysplasia Bayne type II-IV were examined with focus on the International Classification of Functioning and Health, version for Children and Youth (ICF-CY) context. Body function/structure was evaluated by measures of range of motion, grip strength, sensibility and radiographic parameters. Activity was examined by Box and Block Test and Assisting Hand Assessment (AHA). Participation was assessed by Children's Hand-use Experience Questionnaire (CHEQ). Statistical correlations between assessments of body function/structure and activity as well as participation were examined. RESULTS: The mean total active motion of wrist (49.6°) and digits (447°) were less than norms. The mean hand forearm angle was 34° radially. Ulnar length ranged from 40 to 80% of age-related norms. Grip strength (mean 2.7 kg) and Box and Block Test (mean 33.8 blocks/minute) were considerably lower than for age-related norms. The mean score for the AHA was 55.9 and for CHEQ Grasp efficiency 69.3. The AHA had significant relationship with the total range of motion of digits (p = 0.042). Self-experienced time of performance (CHEQ Time) had significant relationship with total active motion of wrist (p = 0.043). Hand forearm angle did not show any significant relationship with Box and Block Test, AHA or CHEQ. CONCLUSION: In radial longitudinal deficiency total range of motion of digits and wrist may be of more cardinal importance to the child's activity and participation than the angulation of the wrist.
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3

Smith, Karen. « Longitudinal Decline of Renal Function in Hypertensive Veterans ». Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/194786.

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Objectives: To determine the association of systolic blood pressure (SBP) and medication to renal function over time in a cohort of hypertensive veterans. Three research questions were addressed. What is the relationship between GFR and SBP in all veterans? In normotensive veterans, what is the relationship between developing hypertension and GFR? In veterans with a hypertension diagnosis, what is the relationship between controlled SBP, anti-hypertensive medications and GFR? Methods: Data were obtained from Southern Arizona Veterans' Affairs Health Care System from January 1, 2000 through December 31, 2006. Inclusion criteria consisted of veterans ≥ 21 and < 90 years of age with at least two SBP measurements and two serum creatinine measurements at least 90 days apart. Analyses were performed using a generalized linear mixed model to address serial correlation. Blood pressure, age, sex, race/ethnicity membership, diabetes, proteinuria, and risk factors for renal failure were examined. First, all eligible veterans’ GFR was modeled over seven years. Second, an inception cohort was formed with veterans who developed hypertension over the study period. Third, veterans with a hypertension ICD-9 formed time-varying controlled/uncontrolled hypertension groups. Medication categories examined in the hypertension groups included angiotensin converting enzyme inhibitor(ACE), betablocker( BB), calcium channel blocker(CCB) monotherapy, or combinations of ACE, BB, and CCB. Results: A total of 39,948 veterans were eligible for the first analysis. There were 3,036 who developed hypertension compared to 8,856 who did not in the second analysis. The third analysis consisted of 25,819 subjects: 12,411 with controlled, 13,406 with uncontrolled SBP. In each analysis, there were first-order interactions between blood pressure*age, and blood pressure*time, making interpretation of the results dependant upon these variables. Overall, GFR decreased over time, increasing blood pressure, and increasing age. ACE, BB, CCB use was associated with higher GFR (1.7, 95% CI 1.4-2.1; 1.0, 95% CI 0.7-1.4; and 0.8, 95% CI 0.3-1.3 ml/minute/1.73m², respectively). Conclusions: These analyses identified significant decrease in GFR over time. The effect of blood pressure on GFR was dependent upon time and age. Persons with controlled BP taking antihypertensive therapy had higher GFR than those taking no medication suggesting that antihypertensive medication use preserves kidney function.
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Blake, Tayler Ann Blake. « Nonparametric Covariance Estimation for Longitudinal Data ». The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu15256491898913.

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5

Dimich-Ward, Helen D. « A comparison of longitudinal statistical methods in studies of pulmonary function decline ». Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/32386.

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Three longitudinal pulmonary function data sets were analyzed by several statistical methods for the purposes of: 1) determining to what degree the conclusions of an analysis for a given data set are method dependent; 2) assessing the properties of each method across the different data sets; 3) studying the correlates of FEV₁ decline including physical, behavioral, and respiratory factors, as well as city of residence and type of work. 4) assessing the appropriateness of modelling the standard linear relationship of FEV₁ with time and providing alternative approaches; 5) describing longitudinal change in various lung function variables, apart from FEV₁. The three data sets were comprised of (1) yearly data on 141 veterans with mild chronic bronchitis, taken at three Canadian centres, for a maximum of 23 years of follow-up; their mean age at the start of the study was 49 years (s.d.=9) and only 10.6% were nonsmokers during the follow-up; (2) retrospective data on 384 coal workers categorized into four groups according to vital status (dead or alive) and smoking behavior, with irregular follow-up intervals ranging from 2 to 12 measurements per individual over a period of 9 to 30 years; (3) a relatively balanced data set on 269 grain workers and a control group of 58 civic workers, which consisted of 3 to 4 measurements taken over an average follow-up of 9 years. Their mean age at first measurement was 37 years (s.d.=10) and 53.2% of the subjects did not smoke. A review of the pulmonary and statistical literature was carried out to identify methods of analysis which had been applied to calculate annual change in FEV₁. Five methods chosen for the data analyses were variants of ordinary least squares approaches. The other four methods were based on the use of transformations, weighted least squares, or covariance structure models using generalized least squares approaches. For the coal workers, the groups that were alive at the time of ascertainment had significantly smaller average FEV₁ declines than the deceased groups. Post-retirement decline in FEV₁ was shown by one statistical method to significantly increase for coal workers who smoked, while a significant decrease was observed for nonsmokers. Veterans from Winnipeg consistently showed the lowest decline estimates in comparison to Halifax and Toronto; recorded air pollution measurements were found to be the lowest for Winnipeg, while no significant differences in smoking behavior were found between the veterans of each city. The data set of grain workers proved most ameniable to all the different analytical techniques, which were consistent in showing no significant differences in FEV₁ decline between the grain and civic workers groups and the lowest magnitude of FEV₁ decline. It was shown that quadratic and allometric analyses provided additional information to the linear description of FEV₁ decline, particularly for the study of pulmonary decline among older or exposed populations over an extended period of time. Whether the various initial lung function variables were each predictive of later decline was dependent on whether absolute or percentage decline was evaluated. The pattern of change in these lung function measures over time showed group differences suggestive of different physiological responses. Although estimates of FEV₁ decline were similar between the various methods, the magnitude and relative order of the different groups and the statistical significance of the observed inter-group comparisons were method-dependent No single method was optimal for analysis of all three data sets. The reliance on only one model, and one type of lung function measurement to describe the data, as is commonly found in the pulmonary literature, could lead to a false interpretation of the result Thus a comparative approach, using more than one justifiable model for analysis is recommended, especially in the usual circumstances where missing data or irregular follow-up times create imbalance in the longitudinal data set.
Graduate and Postdoctoral Studies
Graduate
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6

Li, Daoji. « Empirical likelihood and mean-variance models for longitudinal data ». Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/empirical-likelihood-and-meanvariance-models-for-longitudinal-data(98e3c7ef-fc88-4384-8a06-2c76107a9134).html.

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Improving the estimation efficiency has always been one of the important aspects in statistical modelling. Our goal is to develop new statistical methodologies yielding more efficient estimators in the analysis of longitudinal data. In this thesis, we consider two different approaches, empirical likelihood and jointly modelling the mean and variance, to improve the estimation efficiency. In part I of this thesis, empirical likelihood-based inference for longitudinal data within the framework of generalized linear model is investigated. The proposed procedure takes into account the within-subject correlation without involving direct estimation of nuisance parameters in the correlation matrix and retains optimality even if the working correlation structure is misspecified. The proposed approach yields more efficient estimators than conventional generalized estimating equations and achieves the same asymptotic variance as quadratic inference functions based methods. The second part of this thesis focus on the joint mean-variance models. We proposed a data-driven approach to modelling the mean and variance simultaneously, yielding more efficient estimates of the mean regression parameters than the conventional generalized estimating equations approach even if the within-subject correlation structure is misspecified in our joint mean-variance models. The joint mean-variances in parametric form as well as semi-parametric form has been investigated. Extensive simulation studies are conducted to assess the performance of our proposed approaches. Three longitudinal data sets, Ohio Children’s wheeze status data (Ware et al., 1984), Cattle data (Kenward, 1987) and CD4+ data (Kaslowet al., 1987), are used to demonstrate our models and approaches.
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7

D'Silva, Lindsay Antonio. « Longitudinal characterisation of cardiovascular haemodynamic and autonomic nervous system function in normal pregnancy ». Thesis, Swansea University, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678627.

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Miller, Lindsay A. « The Longitudinal Effects of Cardiac Rehabilitation on Cognition in Older Adults with Heart Failure ». Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1404330197.

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9

Tyson, Philip John. « A longitudinal investigation into the influence of atypical antipsychotics on cognitive function in schizophrenia ». Thesis, University of Hull, 2003. http://hydra.hull.ac.uk/resources/hull:16068.

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Cognitive deficits are a well recognised feature of schizophrenia, with patients showing disproportionate impairments in aspects of memory and executive function. Atypical antipsychotics have shown some success at remediating these deficits which suggests that the basis of the cognitive impairment might be neurochemical in origin. However, the precise nature of this effect is unknown. Mechanisms of action might involve antagonism of 5 HT-2A receptors which results in increased prefrontal dopamine, or the affinity of these medications to dopamine receptors or multiple receptors. Patients with a diagnosis of schizophrenia were recruited for the study within 6 weeks of starting one of the atypical antipsychotics; clozapine, olanzapine, risperidone, quetiapine & amisulpride. They were assessed on clinical variables and a wide battery of cognitive tests at baseline, 9-month-follow-up and 18-month-follow-up. For the analysis the whole group was split into different subgroups according to the neurochemical properties of the individual antipsychotics; • Those with a high affinity for 5HT-2A receptors (risperidone, olanzapine & c1ozapine) vs. those with a low affinity for these receptors (quetiapine & amisutpride). • Those with a preferential affinity for dopamine receptors (risperidone & amisulpride) vs.those with an affinity for multiple receptors (otanzapine, clozapine & quetiapine). • Those with a fast dissociation from the 02 receptor (c1ozapine, quetiapine & amisulpride) vs. those with a slower dissociation from this receptor (olanzapine & risperidone) • In addition the individual medication groups were compared on all measures The main findings were that medications that had a high affinity for 5-HT2A receptors exerted negative effects on some aspects of cognition, whilst those with a low affinity for 5HT-2A receptors exerted beneficial effects. In addition, the individual atypical antipsychotics differed in their cognitive effects. It is concluded that affinity to 5HT-2A receptors is an important determinant of the cognitive response to atypical antipsychotics.
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10

Moysiadi, Aliki. « Relaxation of longitudinal and singlet nuclear spin order as a function of solvent viscosity ». Thesis, University of Southampton, 2018. https://eprints.soton.ac.uk/425870/.

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Extending the storage time of nuclear spin order is an important issue in modern NMR spectroscopy since many NMR and MRI applications are limited by the lifetime of spin states. Under normal circumstances the survival of spin magnetization is limited by longitudinal relaxation (T1) which brings the magnetization back to equilibrium within a few seconds. The conversion of longitudinal into singlet order can extend that lifetime to tens of minutes up to an hour. Most nuclear spin relaxation mechanisms in liquids are a function of the correlation time τc of the molecule, which is linked to the molecular tumbling, and inversely proportional to viscosity. Therefore a lower viscosity would reduce the influence of those mechanisms. The increase in the lifetime of longitudinal (T1) and singlet order (TS) is shown here as the viscosity of common organic solvents decreases. The study includes measurements in liquid and supercritical CO2, that oer an extremely low viscosity regime. The further extension of spin order lifetimes for a singlet bearing molecule in liquid CO2 is presented. There appears to be an upper limit to the extension of the singlet order lifetime that is caused by relaxation mechanisms acting in different directions.
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11

Mobley, M. E., Faith W. Akin, Courtney D. Hall, Owen D. Murnane et Jennifer R. Sears. « Longitudinal consequences of mTBI and blast exposure on vestibular and balance function : preliminary observations ». Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/2461.

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Leonard, John. « Investigation of Lateral-Directional Coupling in the Longitudinal Responses of a Transfer Function Simulation Model ». Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/36077.

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The linear variable stability Transfer Function Simulation Model (TFSM), inspired by the United States Air Force's NF-16D Variable stability In-flight Simulator Test Aircraft (VISTA) and created by Henrik Pettersson, can simulate any desired aircraft. The TFSM represents a non-linear aircraft model with its stability parameters - a collection of gain constants, time constants, damping ratios, and natural frequencies. Stability parameters for aircraft generally fall into two uncoupled modes: longitudinal and lateral-directional. Unfortunately, flight tests using the TFSM exhibited undesired lateral-directional coupling in the longitudinal responses.

An S-turn maneuver, formation flight test, and an uncontrolled simulation with an initial bank angle of 60 degrees were the foundation for the investigation to pinpoint the TFSM's errors. The flight tests and subsequent analysis showed that although this model is highly versatile, it has three fundamental problems. First, the original creation of the TFSM incorrectly assumed that the time rate of change for the pitch angle (in the local-horizontal reference frame) is equal to the body-axis pitch-rate for all flight conditions. Second, the TFSM's dynamics do not contain gravity terms. Third, the TFSM cannot generate the angular rates needed in a turn.

Integrating the aircraft's pitch, roll, and yaw angles with the equations of motion for aircraft fixed the first problem. Unfortunately, resolving this issue only intensified the second two problems. The results from this thesis show that the last two problems are part of the TFSM and cannot be fixed explicitly.
Master of Science

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13

Murray, G. (Graham). « Early development and adult cognitive function in schizophrenia and the general population—a longitudinal perspective ». Doctoral thesis, University of Oulu, 2005. http://urn.fi/urn:isbn:9514278925.

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Abstract Many adults with schizophrenia have cognitive deficits, and many children who go on to develop schizophrenia as adults have subtle sub-clinical signs of early developmental deviance. However, the relationship between early markers of neurodevelopment and later neurocognition remains unclear. The present thesis principally investigates infant neurodevelopment, adolescent scholastic function and adult cognition in the Northern Finland 1966 Birth Cohort (n = 12,058). Proxy markers of neurocognition – developmental milestones and school performance – were collected prospectively. Individuals who went on to develop schizophrenia were identified. School performance in pre-schizophrenic individuals was assessed by teacher ratings (n = 100). Cognition in subjects with schizophrenia was assessed at age 33–35 (n = 61). A representative sample of the general population at risk was studied as a comparison group (school assessments n = 9351; neurocognitive assessment n = 104). The schizophrenia group achieved neuromotor milestones later (p < 0.0001) and performed worse than the control group on all cognitive measures (p < 0.0025). In pooled analyses there were associations between infant motor development and adult cognition in executive function (p = 0.006), verbal learning (p = 0.007) and visuospatial working memory (p = 0.02), (earlier development was linked to better adult cognition) but not in visual object learning. The pattern of associations between development and adult cognition was broadly similar in schizophrenia and the general population, whereas associations between development and adolescent scholastic function were stronger in schizophrenia than in controls (p < 0.05). A complementary neuropsychological case study of spontaneous clinical and cognitive improvement in chronic schizophrenia is also presented, showing that cognitive deficits in schizophrenia do not always represent a static encephalopathy, but can be subject to marked improvement. The possibility of using knowledge about premorbid features to help predict and prevent schizophrenia is also critically reviewed, using the school setting as a practical example. It is concluded that many obstacles remain before knowledge about premorbid features can be translated to preventative interventions. Overall, the results of these investigations are consistent with the hypothesis that in schizophrenia, mild infant motor developmental delay, adolescent scholastic performance and cognitive deficits may be age dependent manifestations of the same underlying neural process. Thus, they may be better considered as part of a single longitudinal syndrome
Tiivistelmä Skitsofreniaa sairastavilla aikuisilla on kognitiivisten toimintojen puutoksia. Kognitiivisia (tiedon prosessoinnin) toimintoja ovat esimerkiksi tarkkaavaisuus, huomiokyky, oppiminen, muisti, asioiden suunnittelu ja ongelmanratkaisu. Monilla lapsilla, jotka sairastuvat aikuisiällä skitsofreniaan, on vähäisiä, kliinisesti merkityksettömiä varhaisen kehityksen poikkeamia tai hitautta. Varhaisen kehityksen ja myöhemmän kognition yhteys on toistaiseksi epäselvä. Tämä tutkimus selvittää varhaisen hermostonkehityksen, nuoruusiän koulunkäynnin ja aikuisiän kognition yhteyttä Pohjois-Suomen 1966 syntymäkohortissa (N = 12 058). Tiedot hermoston tietotoimintoja kuvaavista muuttujista (varhainen kehitys ja koulumenestys) kerättiin prospektiivisesti, samoin tieto skitsofreniaan sairastumisesta. Opettajat arvioivat tutkittavien (n = 100) koulumenestystä ennen sairastumista. Skitsofreniaa sairastavien kognitiivinen suorituskyky arvioitiin 33–35 vuoden iässä (n = 61). Vertailuryhmänä käytettiin edustavaa otosta yleisväestöstä (koulumenestys n = 9351; kognitiivinen suorituskyky n = 104). Skitsofreniaryhmä saavutti motoriset kehityskynnykset (kuten seisomaan ja kävelemään oppiminen) keskimäärin merkittävästi myöhemmin ja suoriutui huonommin kuin kontrolliryhmä kaikissa kognitiivisen suorituskyvyn mittauksissa. Lisäksi varhaisen motorisen kehityksen ja aikuisiän kognitiivisen suorituskyvyn välillä havaittiin yhteys. Erityisesti varhainen motorinen kehitys ennusti hyvää toiminnanohjausta, verbaalista oppimista ja visuospatiaalista työmuistia. Vastaavaa yhteyttä ei havaittu visuaalisen oppimisen alueella. Varhaisen kehityksen ja aikuisiän kognitiivisten toimintojen yhteys oli samantyyppinen sekä skitsofreniassa että yleisväestössä, kun taas varhaisen kehityksen ja nuoruusiän koulumenetyksen yhteys oli vahvempi skitsofreniaan sairastuneilla kuin verrokkihenkilöillä. Yhtenä osatyönä esitetään tapausselostus, jossa kaksi kroonista skitsofreniaa sairastavaa henkilöä toipui spontaanisti sekä kliinisesti ja kognitiivisesti. Tapausselostus osoittaa, että skitsofreniaan liittyvä kognitiivisen tason lasku ei välttämättä heijasta pysyvää aivojen toiminnantason laskua, vaan tila voi huomattavasti korjaantua. Tutkimuksen osana on myös katsaus siitä, missä määrin on mahdollista ennustaa skitsofreniaa sairautta edeltävien piirteiden ja koulussa tehtyjen havaintojen perusteella. Katsauksen valossa on ilmeistä, että on edelleen hyvin vaikea hyödyntää sairautta edeltäviä piirteitä tulevan sairauden ennustamisessa ja etenkin ehkäisyssä. Yhteenvetona voidaan todeta tämän tutkimuksen keskeisten tulosten tukevan hypoteesia, jonka mukaan skitsofreniaan myöhemmin sairastuneilla havaittu lievä varhaisen motorisen kehityksen viive, heikko nuoruusiän koulumenestys ja kognitiivisen tason lasku heijastanevat ikäsidonnaista keskushermoston kehitysprosessia ja voivat olla osa samasta pitkittäisestä oirekokonaisuudesta
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14

Hendrick, David J. « Discordance between cross sectional and longitudinal estimates for the effect of ageing on lung function ». Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33000.

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To evaluate why discordance may occur between regression coefficients from cross sectional and longitudinal analyses when ventilatory function is related to ageing, a population was created by computer, and modelled to simulate functional change during life. The program incorporated the effects of many factors known to influence lung function measurements, which were adjusted experimentally so that their contributions to any discordance could be assessed. Regression analyses showed that significant discordance could be induced if the oldest birth cohort failed to reach the same maximal level of function as the youngest; if a quadratic ageing term was excluded from the independent regression variables; or if the effects of certain confounders were present. Discordance occurred additionally if cross sectional estimates became imprecise, but then the differences (often marked) from longitudinal estimates were not significant. It is concluded that discordance may be fundamental and unavoidable (though explicable), or merely a consequence of imprecision.
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McIlvain, Thomas Robert. « A measurement of the longitudinal-transverse interference structure function from the D(e,e'p) reaction ». Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/28065.

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Su, Weiji. « Flexible Joint Hierarchical Gaussian Process Model for Longitudinal and Recurrent Event Data ». University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1595850414934069.

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Negassa, Abdissa. « A comparative study of methods of analysis of longitudinal data with application to lung function tests / ». Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59840.

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The impact of different methods of analysis of longitudinal pulmonary data was assessed using computer simulation and a real data set. Thirty data sets were generated: ten without random error, ten with a 10% random error and the other ten with a 20% random error. In each data set, three methods of analysis of longitudinal pulmonary data, i.e., piecewise-linear regression, linear regression and the proportional change model, were employed. In the generated data sets the piecewise-linear regression showed a 26% and 20% increase in precision of estimation of effect of exposure over the linear regression and the proportional change approaches, respectively. But such a gain in precision could not be demonstrated when the models were applied to a real data set. The effect of random measurement error in measured FEV$ sb1$ was to increase the standard error of estimation of effect of exposure, hence reduced power.
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Sabina, Theresa Elizabeth. « Longitudinal changes in VOb2smax as a function of fitness training and body composition changes in women ». Virtual Press, 1996. http://liblink.bsu.edu/uhtbin/catkey/1020156.

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Numerous cross-sectional studies have reported an inverse relationship between VO2,,,ax and age. However, few longitudinal investigations have compared the rate of decline in VO2,,.x between women who did or did not report exercise habits consistent with the 1990 ACSM position stand for quantity and quality of exercise. The purpose of this study was to determine if changes in exercise habits and body composition affected age-related changes in VO2.x. Subjects were 91 women (age 40.9 ± 8.8 years at baseline) tested twice between 1973 and 1996 (range of 3.1 - 21.9 years, mean interval of 9.3 ± 4.2 years). The subjects were divided into four physical activity groups based on their reported exercise habits at baseline and follow-up as: non-exercise - exercise (NE-EX; n = 21), NE-NE (n=36), EX-EX (n=19), and EX-NE (n=15). Baseline VOz,,,ax (ml-kg-1-min-1) was significantly higher for the EX vs. NE ( 38.4 ± 8.4 vs.28.8 ± 5.7; f42.2; P<.0001). ANOVA revealed significant differences between the physical activity change groups and mean percent changes in VO2. (% A ml•kg'.min'-yr') (F =10.887; P<.0001) which are listed in the following:NE-NENE-EXEX-EXEX-NE-1.081.58*-1.25-2.21* NE-EX vs. EX-NE; NE-EX vs. EX-EX; and NE-EX vs. NE-NE (P<0.05)There were differences between the following groups: NE-EX vs. EX-NE; NE-EX vs. EX-EX; and NE-EX vs. NE-NE for percent change in VO2max (nl•kg'-min 1•yr 1) with the EX-NE group having the largest decline in VO2max during the follow-up period.Using a multiple regression model after adjusting for the exercise habit groups, the exercise group scheme accounted for 27.3 percent of the variance in percent change in VO2max at step 1 of the analysis (f = 1.09; P < 0.001). Change in percent body fat and change in maximal ventilation accounted for an additional 7.2 percent and 6.5 percent of the variance at steps 2 and 3, respectively. The change in maximal heart rate accounted for an additional 2.5 percent of the variance at step 4, although the statistical significance of the contribution was low (P = 0.057). Increases in body fat and decreases in pulmonary ventilation were found associated with declines in aerobic power while a decline in maximal heart rate between the tests was associated with a decline in percent change in aerobic power.In conclusion, these data demonstrate that: 1) adoption or maintenance of a regular exercise program is associated with less decline in VO2,,. during long-term follow-up compared to women who did not exercisers, and 2) changes in exercise habits, body composition, maximal ventilation, and maximal heart rate accounted for nearly half (43 %) percent of the percent decline per year.
School of Physical Education
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Cassidy, Adrian S. « Optimising the central tracking detector readout at ZEUS & ; measuring the longitudinal structure function at HERA ». Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361108.

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Kramer, Jocelyn Anne. « A longitudinal study of nutritional status, body function and quality of life in inoperable lung cancer ». Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624408.

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Roberts, Kate Hannah. « Longitudinal examination of neurocognitive function and community functioning in patients with recent onset and chronic schizophrenia ». Thesis, University of Hull, 2004. http://hydra.hull.ac.uk/resources/hull:12381.

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Introduction: The importance of quantifying the impact of illness on functional abilities is well recognised. Previous research has indicated that the cognitive impairment associated with schizophrenia may have considerable functional significance (Green, 1996. 2000). However, evidence linking these two domains in schizophrenia research has largely come from cross-sectional or prospective short-term investigations. Thus, the predictive impact of these deficits on daily living is still unclear. The current study examined cross-sectional and longitudinal relationships between cognition and different aspects of community function. It also explored the linearity of the relationship between these domains, focusing on cognitive severity as a mediating factor, as well as task complexity. A better understanding of the degree and nature of functional limitations in schizophrenia may help focus on areas for remediation in order to maximise independence of functioning. Methods: Fifty-four patients with a diagnosis of schizophrenia were recruited from community psychiatric clinics serving the Hull and East Yorkshire, and South Humber Health Authorities. The patient group was initially divided into two categories, 'recent onset' and 'chronic', with the majority of these participants being treated as outpatients (57%). A small cognitive comparative group of twenty non-psychiatric, matched controls was also recruited. Symptoms, cognition and social function were comprehensively assessed at baseline, nine-months and eighteen-months. The Independent Living Skills Survey (ll.SS) and Social Behaviour Schedule (SBS) were utilised to quantify levels of community functioning, whilst a battery of manual and computerised neurocognitive tests were administered in order to establish patterns of cognitive deficit Constellations of clinical and affective symptoms were assessed with the Brief Psychiatric Research Survey (BPRS) and the Hamilton Depression Scale (HADRS). Results: Few differences were demonstrated between the two patient groups on predictor and outcome variables, thus the patient groups were pooled for subsequent analyses. Stepwise regression analyses determined that neurocognitive deficits, and in particular deficits of executive function, were important predictors of some aspects of community functioning in patients with schizophrenia, but not community functioning per se. Clinical and affective symptom variables were also found to significantly predict functional outcomes in the study, including overall social behaviour. In most models the variance explained by symptom variables was greater than that explained by cognitive variables. A non-linear relationship between cognitive functioning and social functioning was also suggested. Level of cognitive performance was found to discriminate social performance, whereby severe cognitive disturbance demonstrated poorer outcomes than either moderate or normal performance groups. However, few differences were found between 'normal performance' and 'moderate deficit' groups on social function scores. The study also implied that neurocognitive function did not differentially affect performance on basic and complex instrumental tasks. Conclusions: These findings validate the hypothesis that neurocognitive deficits and clinical symptoms are important 'rate-limiting' factors, but cannot support the notion that neurocognitive impairments are functionally more important than the clinical symptoms of the disorder. A combined psychopharmacological and psychosocial approach that takes account of an individual's neurocognitive deficits would therefore appear to offer a reasonable treatment stratagem. The study also suggests that further investigation in larger studies with increased analytical strategies for capturing the non-linear reciprocal relationships between cognition and social function are needed. Finally, a substantial unexplained variance in social functioning exists, which indicates the need for investigations to evaluate other candidate risk factors in relation to both the clinical and cognitive symptoms of the disorder.
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Levin, Anna O. « A Longitudinal Examination : The Relationship between Sexuality and Mental Health-Related Quality of Life for Breast Cancer Survivors ». The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1252695725.

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Carlstedt, Kerstin. « Palatal plate therapy in children with Down syndrome : a longitudinal study of effects on oral motor function / ». Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-410-4/.

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Sherrill, David Semmes. « Measurements of the longitudinal nuclear magnetic resonance in superfluid helium-3 as a function of magnetic field / ». The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487329662147149.

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Tooley, Ursula Ann. « Longitudinal Analysis of Sleep Disruption in Pediatric Subjects with Down Syndrome : Effects on Language and Executive Function ». Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/322063.

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Staaf, Johan. « Childhood Obesity and Islet Function ». Doctoral thesis, Uppsala universitet, Institutionen för medicinsk cellbiologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-313310.

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The prevalence of childhood obesity and Type 2 Diabetes Mellitus (T2DM) has increased during recent decades. T2DM is accompanied with functional changes in the islets of Langerhans, which can be identified early in the pathogenesis. The aim of this thesis was to explore how metabolic changes caused by obesity early in life relate to islet function prior to overt T2DM. To address this, Uppsala Longitudinal Study of Childhood Obesity (ULSCO) was established (paper I). Initially, the association between palmitate and insulin secretion was investigated using a translational approach with obese and lean normoglycemic juveniles and isolated human islets (paper II). Secondly, dynamics of islet-hormones insulin and glucagon, and gut-hormones glucagon like-peptide 1 (GLP-1) and glicentin (paper III) and magnetic resonance imaging of pancreatic fat fraction (PFF) (paper IV) were studied in association to glucose tolerance and beta-cell function. Finally, a novel method of analysing shape features of oral glucose tolerance test (OGTT) curves was introduced and evaluated (paper V). Obese subjects had high prevalence of prediabetes and metabolic syndrome (MetS) (paper I). In obese pre-pubertal children with elevated palmitate levels, hyperinsulinemia was observed (paper II). In contrast, obese pubertal adolescents with similar palmitate levels showed moderate insulin levels during OGTT with delayed first phase insulin response. To explore mechanisms for these variations, isolated human islets were exposed to palmitate for different time periods in vitro. After 2 days accentuated insulin response was observed. Impaired beta-cell function and apoptosis were evident after 7 days, however. Hyperglucagonemia and disturbed GLP-1 and glicentin levels were associated with obesity and glycaemic status, with fasting glicentin being predictive of prediabetes (paper III). Furthermore, PFF was increased in obese subjects and associated to MetS and visceral adipose tissue, but not to beta-cell function (paper IV). OGTT curves were converted into geometric centres, centroids, which correlated with differences in glucose tolerance (paper V). In conclusion, the islet function in obese children was associated with elevated levels of palmitate, but not pancreatic fat. Fasting palmitate and glicentin levels, as well as centroid analyses of OGTT curves, could potentially identify obese children at risk of prediabetes and subsequent T2DM.
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Gupta, Nishant. « The NHLBI Lymphangioleiomyomatosis (LAM) Registry : Longitudinal Analysis to Determine the Natural History of LAM ». University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1504879473662385.

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Grebenyuk, Julia [Verfasser], et ROBERT [Akademischer Betreuer] KLANNER. « Measurement of the longitudinal proton structure function with the ZEUS detector at HERA / Julia Grebenyuk. Betreuer : Robert Klanner ». Hamburg : Staats- und Universitätsbibliothek Hamburg, 2015. http://d-nb.info/1068931558/34.

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Schwartz, Jason. « Experimental study of initial state radiative events at HERA and a measurement of the proton longitudinal structure function ». Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=104719.

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A first measurement of the radiative contribution to deep inelastic electron-proton scattering has been performed with the ZEUS detector at HERA. Results show consistency with predictions made by the HERACLES Monte Carlo program. New calibration and simulation of the far luminosity measurement system, including a photon calorimeter and two aerogel Cherenkov detectors, have been implemented. Both calibration and simulation were applied to tag photons produced in the initial state radiative process. These tagged events were used to perform measurements of the deep inelastic ep scattering reduced cross section down to momentum transfer squared, Q2 = 3.0 GeV2, a region normally inaccessible to ZEUS. A determination of the radiative contribution to deep inelastic scattering has aided in the measurement of the structure functions F2 and FL, which were simultaneously extracted in the kinematic region 8.0 GeV2 < Q2 < 130 GeV2 and 2.5 × 10−4 < x < 0.005, where x is associated with the fraction of momentum carried by the interacting quark, using collision data at three centre-of-mass energies, 318 GeV, 251 GeV and 225 GeV.
La contribution radiative à la diffusion in èlastique profonde èlectron-proton a ètè mesurèe pour la première fois avec le dètecteur ZEUS à HERA. Les rèsultats dèmontrent un accord avec les prèdictions faites par le programme Monte-Carlo HERACLES. De nouvelles calibration et simulation du système èloignè de mesure de la luminositè, incluant un calorimètre à photons et deux dètecteurs Cherenkov en aèrogel, ont ètè effectuèes. Ces calibration et simulation ont ètè toutes deux utilisèes pour identifier les photons produits dans le processus de radiation de l'ètat initial. Les èvènements ainsi choisis ont permis de mesurer la section efficace rèduite de diffusion inèlastique profonde ep à des valeurs du carrè du transfert de quantitè de mouvement aussi basses que Q2 = 3.0 GeV2, une règion cinèmatique normalement non-accessibleà ZEUS. Une dètermination de la contribution radiative à la diffusion inèlastique profonde a aidè les mesures des fonctions de structure F2 et FL, qui ont ètè ex- traites simultanèment dans la règion cinèmatique 8.0 GeV2 < Q2 < 130 GeV2 et 2.5 × 10−4 < x < 0.005, où x peut être associè à la fraction de la quantitè de mouve- ment du proton participant à la rèaction, et ce en exploitant les donnèes de collisions prises à trois ènergies du centre de masse, 318 GeV, 251 GeV et 225 GeV.
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Turner, Stephen William. « A longitudinal study of airway responsiveness, lung function and respiratory symptoms from early infancy to eleven years of age ». Thesis, University of Newcastle upon Tyne, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397346.

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Cai, Anika. « Longitudinal investigation of middle ear function using multi-frequency, multi-component tympanometry from birth to six months of age ». Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/19329.

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Objectives: The specific goals of this study were: 1) To understand the mechano-acoustical properties of the normal ear canal and middle ear and its maturation as a function of age using conventional and high frequency tympanometry 2) to establish tympanometric guidelines and normative data of the normal ear canal and middle ear in infants birth to 6 months of age. Design: Thirty-one normal hearing newborns were tested longitudinally in 1-month intervals up to 6 months of age for a total of 6 visits. Tympanograms were recorded and the distributions of patterns were analyzed using the Vanhuyse model at 226 Hz, 678 Hz, and 1000 Hz. Additionally, tympanometric recordings of admittance (Ya), susceptance (Ba), and conductance (Ga) were analyzed at 226 Hz and 1000 Hz probe tones. Lastly, the variation of compensated susceptance and conductance were recorded at extended frequencies from 250-2000 Hz in 50 Hz intervals for 16 infants. Results: Results showed that 1000 Hz tympanograms were the simplest to quantify as most recordings were single-peaked. 226 Hz and 678 Hz recordings were often multi-peaked. Both positive and negative admittance and susceptance tail values increased with age for 226 Hz and 1000 Hz. However, tail values at 1000 Hz increased faster than for 226 Hz. Negative tail values were smaller compared to positive tail values which resulted in smaller compensated admittance values for the positive tails compared to negative tails across all 6 visits. Admittance magnitude decreased with age at 226 Hz as susceptance increased and conductance decreased. However, at 1000 Hz, admittance magnitude increased as susceptance remained relatively constant and conductance increase. Conclusion: Results suggest that the infant middle ear and ear canal develop towards compliance with age although is not yet a purely acoustically compliant system by 6 months of age, particularly at high frequencies. An increase in volume in the middle ear cavity, reduction of middle ear debris, and overall decrease in resistive elements may be contributing to these changes. Significant differences were observed between each visit and warrant the use of age-specific norms when applying tympanometric data to infants below 6 months of age.
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PEREZ, OSCAR HERNAN POLANCO. « DETERMINATION OF THE LONGITUDINAL COMPONENT OF ELETROMAGNETIC FIELSD PRODUCED BY SURFACE CURRENT DENSITIES, IN APPLICATIONS OF DIADIC GREENNULLS FUNCTION ». PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1998. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=8130@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Neste trabalho desenvolve-se uma técnica para determinação da componente longitudinal do campo elétrico gerado por uma densidade superficial de corrente. A metodologia proposta baseia-se na diádica de Green da região em consideração, sendo estudadas regiões interiores em que existe uma solução analítica da equação de onda escalar em coordenadas ortogonais e regiões exteriores, em sistemas de coordenadas esféricas e cilíndricas. Para cada uma das soluções, mostra-se a convergência da expressão obtida para a componente longitudinal do campo elétrico, expressa por uma série ou integrais de funções modais. Baseado na metodologia desenvolvida, elabora-se um modelo de análise para determinação de campos e impedância característica em cabos coaxiais de seção arbitrária. O modelo é aplicado a cabos de seção circular e retangular. A metodologia de determinação de campos por diádicas de Green é ainda aplicada à análise de cabos coaxiais de seção retangular, com estais de fixação do condutor interno, localizados periodicamente.
It is developed a method for the determination of the longitudinal component of the electric field generated by a surface current density in the interior or the exterior regions. The proposed method is based on the dyadic Green´s function of the region under consideration, beeing analysed interior regions, assuming the knowledge of the analytical solution for the scalar wave equation in the orthogonal coordinate systems and external regions, using spherical and cylindrical coordinate systems. For the each solution, it is shown the convergence of the expression obtained for the longitudinal component of the electric field. Based on the developed method, a model of analysis is elaborated to determine the field and the characteristics impedance of coaxial cables of arbitrary cross section. The model is applied to cables with circular and rectangular sections. The dyadic Green´s function method is finally applied to the analysis of coaxial cables with internal metallic struts periodicaly placed.
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Bridges, Jarom. « The Effect of Foot Strengthening Exercise on Dynamic Function of the Medial Longitudinal Arch in Runners : A Preliminary Report ». BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5626.

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Therapeutic exercise has previously been shown to alter the static height of the medial longitudinal arch (MLA). It is still unknown, however, if these effects carry over into dynamic activities. PURPOSE: To determine if an 8-week foot strengthening exercise program increases static arch height and reduces vertical deformation of the MLA during mid-stance in running.METHODS: Thirty-four recreational runners (17 males, 17 females) have completed this ongoing study (age 24.06 ± 3.61 years, body mass 68.63 ± 12.95 kg, and height 173.34 ± 9.54 cm). To date, 22 subjects have been assigned to the control group (8 weeks of normal running) and 12 to the foot strengthening group (8 weeks of foot strengthening, along with normal running). Static arch height (SAH) and dynamic arch drop (DAD) were measured at baseline and following the 8-week intervention using Vicon motion analysis. Reflective markers were placed on the proximal and distal ends of the 1st and 5th metatarsals. These 4 markers were recorded in static double leg stance to estimate SAH, and in single leg mid-stance to give a measure of DAD during treadmill running at a self-selected pace. Ten-second trials were recorded at minutes 3 and 4 during running and DAD was evaluated for right and left feet by comparing arch height in mid-stance to the SAH. Following the intervention, data for SAH and DAD were compared across time points and statistical analysis performed to identify differences in the amount of change in SAH and DAD between groups. RESULTS: There was no difference noted in DAD between the groups as a whole, but the change in DAD from baseline to the end of week 8 was statistically significant for those in the foot strengthening group with an initial DAD of ≥ 3.80 mm (p < .028). There was also a statistically significant increase in SAH in the foot strengthening group compared to the control group (p = .013). CONCLUSIONS: These preliminary data suggest that the foot strengthening intervention was effective in increasing SAH compared to the control group. The intervention was most effective at decreasing DAD in those with the largest amount of DAD at baseline. At this time it is unknown whether this decrease in arch drop is associated with performance benefits or decreased injury risk in the recreational runner, and further research is needed to determine the clinical significance of these findings.
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Tee, James J. L. « RPGR-associated retinitis pigmentosa : a multi-modal longitudinal study investigating retinal structure and function in preparation for gene therapy trials ». Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10058710/.

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RPGR-associated retinitis pigmentosa is among the most severe forms of RP and is an important target for gene therapy trials. There is however a lack of robust clinical data on this condition. The aim of this thesis is therefore to investigate and characterise the natural history with protocol-driven, prospectively acquired structural and functional data on molecularly confirmed subjects. Investigations into retinal structure were conducted with data obtained from protocol driven spectral domain-optical coherence tomography and autofluorescence imaging. Visual function assessments were performed with visual acuity, contrast senstivity and Octopus 900 static perimetry testing using a customised grid. Three-dimensional topographic models were created from perimetry data with the use of advanced software to produce volumetric metrics for further interrogation. Quantitative analyses of structure or function were comprehensively undertaken with each modality to bilaterally characterise baseline dimension and progression rates of subjects. In addition, a broad range of metrics were investigated to identify ones that are most sensitive and suitable for use in characterising the natural history, with the expectation that these metrics will be utilised in studying future outcomes of treatment trials. In general, good overall interocular symmetry was found however significant variation exists across subjects. Indices to quantify intraocular symmetry were constructed and explored. Associations between progression, age, baseline dimension and genotype were investigated. Younger subjects typically possessed greater baseline dimensions. Faster rates of progression were found in those with better baseline structure and function. Exponential decline rates for each modality were calculated with a mixed-models method using pooled data from the cohort to estimate overall progression. In comparison to functional metrics, structural metrics were more sensitive in detecting change with the characterisation of greater progression rates. The optical coherence tomography based ellipsoid zone (EZ) width metric was found to be more precise compared to the EZ area metric. With regards to autofluorescence based metrics, those derived from outer borders of hyperautofluorescent rings were superior to metrics derived from inner borders of rings. Ring area was found to be more robust compared to ring diameter metric. Functional metrics are nevertheless important as they reflect the subject's visual experience. Visual function in the earlier stages of disease is best characterised by metrics of peripheral function with decline in the later stages better characterised by metrics of central function. Work presented in this thesis is expected to provide a much-needed resource to inform recently commenced treatment trials, in addition to providing prognostic information to clinicians caring for individuals with the condition.
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Yao, Huan. « Precision Measurement of Longitudinal and Transverse Response Functions of Quasi-Elastic Electron Scattering in the Momentum Transfer Range 0.55 GeV /c ≤ |q| ≤ 1.0 GeV /c ». Diss., Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/152421.

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Physics
Ph.D.
Coulomb Sum Rule states that the integration of the longitudinal response of a nucleus over the range of energy excitation dominated by quasi-elastic proton knock-out process should be equal to the total number of protons in the nucleus. The test of Coulomb Sum Rule will shed light on the question of whether or not the properties of nucleon are modified in the nuclear medium. In order to test the Coulomb Sum Rule in nuclei, a precision measurement of inclusive electron scattering cross sections in the quasi-elastic region was performed at Jefferson Lab. Incident electrons with energies ranging from 0.4 GeV to 4 GeV scattered from 4He, 12C, 56Fe and 208Pb nuclei at four scattering angles ( 15°, 60°, 90°, 120°) and scattered energies ranging from 0.1 GeV to 4 GeV. The Rosenbluth method with proper coulomb corrections is used to extract the transverse and longitudinal response functions at three-momentum transfers in the range 0.55 GeV/c ≤ |q| ≤ 1.0 GeV/c. The Coulomb Sum Rule is determined in the same |q| range and compared to predictions. This work is supported by the Department Of Energy through grant DE-FG02-94ER40844.
Temple University--Theses
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Carey, Iain Miller. « The cross-sectional and longitudinal effects of environmental tobacco smoke, fresh fruit and adiposity on lung function in children and adults ». Thesis, St George's, University of London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367519.

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Nikolich‐Zugich, Tijana. « Effects of High Vs. Reduced‐Dose Melphalan For Autologous Bone Marrow Transplantation in Multiple Myeloma On Pulmonary Function : A Longitudinal Study ». Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/623514.

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A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.
Bone marrow transplants (BMT, also hematopoietic stem cell transplants or HSCT/SCT) are one of the greatest medical achievements of the 20th century. They offer a treatment for a host of malignant and nonmalignant hematopoietic disorders, genetic diseases and solid tumors that could otherwise be fatal. Studies have found that 60% of patients undergoing BMT develop pulmonary complications (PC), and 1/3 of those require intensive care after transplantation. Despite the potential pneumotoxicity of induction agents, to date there have been no longitudinal studies following pulmonary function in this high‐risk patient population. This study reviewed patient who underwent autogeneic bone marrow transplant for multiple myeloma at Banner University Medical Center – Tucson (formerly University of Arizona Health Network) from January 1, 2003 through December 31, 2013. Pretransplant evaluatin and pulmonary function testing data were obtained and stratified between high dose (standard) Melphalan (200 mg/ms2) and reduced dose (140 mg/ms2). Statistically significant differences were present between the 2 groups at baseline for DLCO but disappeared at 6 and 12‐month followup, while a statistically significant difference for FEV1/FVC ratio was seen at baseline and 6 months but disappeared at 12‐month follow‐up. There were no statistically significant differences seen with FEV1 between the two groups. Given there is no difference in mortality and relapse outcomes between the groups, the standard of care dosing for Melphalan is not associated with an increase in pulmonary morbidity.
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Jashari, Haki. « The effect of pressure afterload due to aortic coarctation on left ventricular function in children ». Doctoral thesis, Umeå universitet, Medicin, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-128126.

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Background: Coarctation of the aorta (CoA) is a congenital heart disease which represents a narrowing of the proximal descending aorta, hence increasing pressure afterload to the left ventricle (LV). Conventional treatment of native CoA is surgical repair, however potential recurrence or other related complications e.g. aortic rupture, heart failure and cerebrovascular events are common. Thus, lifelong follow-up of these patients is required. Echocardiography is the most patient’s friendly method to evaluate CoA and in particular its effect on LV function. Moreover, the novel speckle tracking echocardiography (STE) is an important method to assess subclinical LV dysfunction, a technique that promises better evaluation of LV function in these patients. The aims of this thesis were to review the literature on LV function in children with CoA using myocardial deformation imaging technologies, hence, to better understand the current knowledge and vagueness of the scientific evidence. We also aimed to study the effect of early CoA repair on the structure and function of LV and ascending aorta. In addition, we wished to establish in a meta-analysis format normal values of speckle tracking derived strain and strain rate values. Methods: Study 1. We have systematically searched the PubMed, and studies that fulfilled the inclusion criteria were critically analyzed and presented on a narrative form. Study 2 and 3. In addition to conventional echocardiographic measures of LV and ascending aorta, we measured longitudinal strain and strain rate of the LV using a vendor independent software, TomTec. We have also measured the aorto-septal angle (AoSA). Data was compared with normal healthy controls. Study 4. Electronic databases were systematically searched and suitable studies were meta analyzed using Comprehensive meta-analysis version 3 software. Results: Study 1. In 7/4945 included articles, 123 and 76 patients with congenital aortic stenosis (CAS) and CoA were reported, respectively. Normal conventional LV function, with subclinical myocardial dysfunction were reported in all studies before intervention. After intervention, a consistent improvement of myocardial deformation parameters was documented, even though not reaching normal values. Study 2. In 21 patients with CoA, LV function significantly improved after intervention (p <0.001), however normal values were not reached even at medium-term follow-up (p = 0.002). Medium-term longitudinal strain correlated with pre intervention LV ejection faction (EF) (r = 0.58, p = 0.006). Medium-term subnormal values were more frequently associated with Bicuspid aortic valve (BAV) (33.3% vs. 66.6%; p <0.05). Study 3. AoSA was abnormally wide before intervention, in particular at peak ejection in the descending aorta (p <0.0001), and correlated with CoA pressure gradient. After intervention, AoSA normalized and significantly correlated with the increase of LV cavity function and overall LV deformation parameters. Study 4. In a meta-analysis of 28/282 studies including 1192 subjects, strain and strain rate values were established. Longitudinal strain normal mean values varied from -12.9 to -26.5 (mean, -20.5; 95 % CI, -20.0 to -21.0). Normal mean values of circumferential strain varied from -10.5 to -27.0 (mean, -22.06; 95 % CI, -21.5 to -22.5). Radial strain normal mean values varied from 24.9 to 62.1 (mean, 45.4; 95 % CI, 43.0 to 47.8). Meta-regression showed LV end-diastolic diameter as a significant determinant of variation of longitudinal strain. Longitudinal systolic strain rate was significantly determined by age and radial strain was influenced by the type of vendor used. Conclusion: The systematic review showed subclinical LV dysfunction in children with CoA before and after correction. However, since most of the patients were operated at an older age and had preserved LV EF, the effect of early intervention on LV function was only speculated. Our children with CoA who were operated at an earlier age showed LV subclinical dysfunction even at medium- term after intervention while the AoSA returned to normal shortly after intervention. Lower longitudinal strain values were found in patients with LV dysfunction (LV EF <50%) before intervention and BAV. Finally, normal range values for strain and strain rate have been established and seem to be influenced by patients’ age, LV end-diastolic diameter and vendor used.
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Aissaoui, Nadia. « Analyse du rôle des fonctions ventriculaires longitudinales dans les défaillances cardio-circulatoires graves ». Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST0100.

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Les analyses des fonctions ventriculaires gauche (VG) et droite (VD) et des pressions de remplissage sont des éléments importants dans le contexte des défaillances cardio-circulatoires graves car elles ont des conséquences diagnostiques et pronostiques avec un impact sur les prises de décisions thérapeutiques. Toutefois, l'évaluation de la fonction myocardique en cas de choc reste difficile pour des raisons physiopathologiques et technologiques. Les paramètres de fonction ventriculaire longitudinale (FVL) pourraient avoir un intérêt dans ce domaine car ils permettent une évaluation directe d'une composante majeure de la mécanique ventriculaire. Ces paramètres ont été évalués chez les défaillances chroniques stables et ont montré leurs intérêts diagnostiques et pronostiques. Ils restent très peu étudiés dans les contextes aigues et graves
Despite advances in management and therapies, cardiogenic shock remains a clinical challenge with high mortality rates.The analysis of left and right ventricular functions and filling pressures are important in this context because they had diagnostic and prognostic consequences with impact in therapeutic decisions. Nevertheless, the assessment of myocardial function remains difficult for physiopathologic and technical reasons. The parameters of longitudinal ventricular function (LgVF) could have an interest in this context because they permit a direct assessment of a major component of ventricular mechanics whereas ejection fraction remains a global evaluation. These indices were assessed in chronic and stable heart failure patients and were found to have prognostic and diagnostic interests. Though, they were not evaluated in the context of acute and severe cardio-circulatory failures
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Hayek, Jorge Elie. « "Avaliação da densidade ótica perimplantar cervical em controle longitudinal de implantes com função oclusal imediata em maxila" ». Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/23/23139/tde-11112005-115646/.

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A proposta neste estudo foi avaliar as alterações da densidade ótica do osso alveolar perimplantar cervical em controle longitudinal, por meio de radiografias periapicais digitalizadas de dez pacientes, nos quais foram instalados seis implantes na maxila submetidos à função oclusal imediata, mediante a instalação de uma prótese fixa 24 horas após a cirurgia. Todos os pacientes foram avaliados clinicamente, com exames da análise da freqüência de ressonância, além de controle radiográfico. Foi utilizada a técnica radiográfica intrabucal do parale lismo, com cone longo, sendo que o feixe de raios X incidiu perpendicularmente ao longo eixo do implante. Os controles radiográficos foram realizados na instalação da prótese, após 6 meses e após 12 meses. As radiografias obtidas foram então capturadas por uma câmera de vídeo (preto e branco) por meio de um microscópio ótico (40 vezes de aumento). Devido à ampliação utilizada, os implantes tiveram suas imagens digitalizadas em 2 etapas (metade direita e metade esquerda), sendo consideradas como amostras independentes. Após a sobreposição de um gabarito sobre a imagem, com a finalidade padronizar as áreas a serem estudadas, foram analisadas as densidades óticas na área de interesse osso + implante e na área de controle implante (onde não é esperada alteração) por meio do software ImageLab. Para a correção de possíveis variações na densidade da radiografia e projeção geométrica oriundas da metodologia empregada, foi utilizada uma equação matemática para validar a análise dos dados obtidos. Os resultados mostraram que ocorreu variação percentual da densidade ótica na área de interesse (osso + implante) nos primeiros seis meses (T2) com diminuição de aproximadamente 5% para o lado direito e diminuição de aproximadamente 6% para o lado esquerdo em relação às radiografias iniciais (T1) e após doze meses, a diminuição da densidade ótica estabilizou-se, não sendo encontradas alterações estatisticamente significantes em relação ao período correspondente entre T2 (seis meses) e T3 (doze meses). Os resultados da análise digital das radiografias periapicais demonstraram coincidência com os resultados da análise da freqüência de ressonância e exame clínico dos implantes e demonstraram um aspecto compatível com o sucesso dos implantes osteointegrados com função imediata na maxila.
The aim in this study was the evaluation of the variations of the perimplantar optical bone density at the cervical region in a longitudinal control, by the use of digitized radiographs of ten patients, who received six implants installed in the maxilla and submitted to immediate occlusion function, through fixed prosthesis installed 24 hours after the surgery. All the patients were observed in clinical control, with resonance frequency analysis and also radiographic control. It was performed a intraoral radiograph using the paralleling technique, with the long cone and the beam of x-ray aimed perpendicular to the long axis of the implant. The radiographic controls were done at the time of the installation of the prosthesis, after six months and after twelve months after the first control. The obtained radiographs were captured by a black and white video camera by an optical microscope (40 times of magnification). Due to the utilized magnification, the implants have their images digitized in two steps: half right and half left, and they were considered as independent samples. After the superimposition of a standardized pattern, to help the standardization of the areas of the study, it was analyzed the optical density at the areas of interest bone + implant and at areas of control bone (where it is not hope changes) through the software ImageLab. To correct possible variations of the effect of the absence of standardization of the geometric projection and the radiographic density, it was realized a mathematic equation and it was obtained a correction factor of density in order to compensate. The results sho wed that there were percentage variation of the optical density at the area of interest (bone + implant) at six months (T2) showed a decreased of about 5% for the right side and showed a decreased of about 6% for the left side when analyzed the first control and after twelve months no significant statistical difference was observed between the T2 period (six months) and T3 period (twelve months). The results of digital analysis from the intraoral radiographs showed as the same as the results of resonance frequency analysis and the clinic examination of the implants and showed a success of implants installed in the maxilla with immediate occlusion function.
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Derdikman-Eiron, Ruth. « Symptoms of Anxiety and Depression and Psychosocial Function in Males and Females From Adolescence to Adulthood : Longitudinal Findings from the Nord-Trøndelag Health Study ». Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Det medisinske fakultet, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18248.

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Angst- og depresjonssymptomer og psykososial funksjon hos gutter og jenter fra ungdomstid til voksen alder: Longitudinelle funn fra Helseundersøkelsen i Nord-Trøndelag I dette longitudinelle forskningsprosjektet utforsket vi den psykososiale funksjonen til ungdommer og unge voksne med og uten symptomer på angst og depresjon. Deltakerne ble vurdert på tre tidspunkter: 1995-97 - Young HUNT 1 (rundt 9000 deltakere), 2000- 2001 - Young HUNT 2 (omtrent 2500 deltakere) og 2006 - HUNT 3 (1300 deltakere). Vi fant at forekomsten av symptomer på angst og depresjon var høyere hos jenter enn hos gutter. Tidligere og vedvarende symptomer på angst og depresjon hadde imidlertid mer negative konsekvenser for gutter enn for jenter. I tverssnittundersøkelsen var sammenhengene mellom slike symptomer og lavere subjektiv velvære og selvfølelse, større problemer med læring samt mindre hyppig samvær med venner, mer utbredt hos gutter enn hos jenter. Resultatene av den longitudinelle studien styrket og utvidet disse funnene ytterligere. Tidligere, nåværende eller vedvarende symptomer på angst og depresjon var forbundet med mer redusert funksjon hos gutter enn hos jenter. Symptomdebut mellom første undersøkelse og oppfølgingstidspunktet var relatert til mindre hyppig samvær med venner for gutter, men ikke for jenter. Dessuten hadde gutter etter at symptomene bedret seg, fortsatt mer problemer med atferd og læring, de møtte venner sjeldnere og rapporterte lavere subjektiv velvære og selvfølelse enn gutter som ikke hadde symptomer på noen av tidspunktene. Ingen tilsvarende forskjeller ble funnet blant jentene. Subjektiv velvære og hyppighet av samvær med venner i ungdomstida framsto som de viktigste prediktorene for fungering i voksen alder. Ungdommenes subjektive velvære predikerte samvær med venner for menn, jobbtilfredshet for kvinner og opplevelse av samfunnstilknytning for begge kjønn. Hyppighet av samvær med venner i ungdomstida predikerte støtte fra venner hos kvinner, og samboerskap i voksen alder hos begge kjønn. Resultatene tilsier at en bør være oppmerksom på redusert fungering hos menn og kvinner med symptomer på angst og depresjon, både i utredning og i behandling.
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Marioni, Larissa da Silva. « A influência da qualidade do professor sobre a proficiência dos alunos : uma análise longitudinal ». Universidade Federal de Juiz de Fora, 2014. https://repositorio.ufjf.br/jspui/handle/ufjf/715.

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Uma importante questão que vem recebendo a atenção de estudos na literatura de economia da educação se refere a identificação dos insumos relevantes para o aprendizado escolar das crianças e a possibilidade de implementação de políticas públicas que sejam efetivas. Em particular, os resultados de desempenho educacional decorrentes da qualidade do professor não são consensuais. Uma questão que ainda precisa ser melhor investigada é se um professor de boa qualidade afeta positivamente o desempenho escolar do aluno no decorrer do tempo. Nesse sentido, o objetivo do presente estudo é identificar o impacto das contribuições dos professores para o aprendizado através da proficiência dos alunos de escolas públicas e privadas em municípios selecionados do Brasil. A partir dos microdados longitudinais do projeto GERES - Geração Escolar, que acompanhou o desempenho dos alunos da primeira etapa do Ensino Fundamental nos anos de 2005 a 2008 utilizou-se a Função de Produção Educacional (FPE) incluindo os efeitos fixos de alunos, professores e o match entre eles para detectar o efeito da qualidade observada do professor e buscar evitar o viés decorrente da omissão de variáveis sobre o resultado dos alunos. A relevância do formato longitudinal dos dados possibilita avaliar a evolução do aprendizado das crianças e utilizar hipóteses menos restritivas na estimação dos resultados. Esse tipo de especificação, até onde foi investigado, não foi utilizado na literatura empírica do efeito do professor na proficiência dos alunos. A partir dos resultados foi verificado que com o controle dos efeitos fixos, inclusive do match, questões como o professor possuir outro trabalho tem impacto negativo na proficiência de seus alunos. As variáveis como educação, experiência e renda são significativas para português e os resultados são coerentes. Já para matemática, essas mesmas variáveis não são significativas, indicando que as características não observadas, quando controladas são capazes de explicar as diferenças nas notas. Através dos coeficientes das dummies dos professores o aluno que muda do pior para o melhor professor em português pode sair do primeiro nível de aprendizagem e atingir o terceiro de acordo com a escala do GERES. O aluno que muda do pior para o melhor professor em matemática pode sair do primeiro nível de aprendizagem e ir para o quinto nível de acordo com a escala para esta proficiência.
An important issue that has received attention in studies of the economics of education literature refers to identifying relevant inputs to children’s educational performance and the possibility of implementing public policies that are effective. In particular, the results of educational performance coming from teacher quality are not consensual. One issue that still needs to be investigated is whether a good quality teacher positively affects the academic performance of students over time. In this sense, the aim of this study is to identify the impact of teachers’ contributions to learning through the proficiency of students in public and private schools in selected municipalities in Brazil. From the longitudinal micro project GERES – Geração Escolar, which accompanied the students' performance in the first stage of elementary school in the years 2005 to 2008, we used the educational production function (EPF) including fixed effects for students, teachers and the match between them to detect the effect of the observed teacher’s quality and seek to avoid the bias caused by the omission of variables on the students’ outcomes. The relevance of longitudinal data allows to evaluate the evolution of children's learning and use less restrictive assumptions on the estimation results. This type of specification, as far as we investigated, was not used in the empirical literature of the teacher’s effect in student proficiency. From the results it was found that controlling for fixed effects, including the match, issues such as the teacher has other work has a negative impact on the proficiency of their students. Variables such as education, experience and income are significant for reading and the results are consistent. For math, these same variables are not significant, indicating that the unobserved characteristics when controlled are able to explain the differences in the notes. Using the coefficients of the dummies of the teachers, students that changes from worst to best teacher in portuguese can achieve the third level of learning according to the scale of GERES. A student who changes from worst to best math teacher can leave the first level of learning and achieve the fifth level in accordance with the scale for this proficiency.
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Deng, Yangyang. « A Study of the Relationship between Childhood Body Size and Adult Blood Pressure, Cardiovascular Structure and Function ». VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3408.

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BACKGROUND: Little is known of the effects of obesity, body size and body composition, and blood pressure (BP) in childhood on hypertension (HBP) and cardiac structure and function in adulthood due to the lack of long-term serial data on these parameters from childhood into adulthood. In the present study, we are poised to analyze these serial data from the Fels Longitudinal Study (FLS) to evaluate the extent to which body size during childhood determines HBP and cardiac structure and function in the same individuals in adulthood through mathematical modeling. METHODS: The data were from 412 males and 403 females in the FLS. Stature and BMI parameters were estimated using the Preeze-Baines model and the third degree polynomial model to describe the timing, velocity and duration of these measure from 2 to 25 years of age. The biological parameters were related to adult BP and echocardiographic (Echo-) measurements using Generalized Linear Models (GLM). RESULTS: The parameters of stature and BMI were compared between male and female to their overall goodness of fit and their capabilities to quantify the timing, rate of increase, and duration of the growth events. For stature parameters, the age at onset and peak velocity was earlier for girls; but the peak velocity was greater in boys; the velocity at onset was about the same for boys and girls; and stature at onset, peak velocity and adult was greater for boys. For BMI parameters, boys tended to have larger BMI values than girls, but the rates of change in BMI were almost the same; there was no sex difference in the timing of BMI rebound, but there was for the age of the peak velocity of BMI and maximum BMI, both of which were earlier in girls than in boys. CONCLUSIONS: Changes in childhood stature and BMI parameters were related to adult BP and Echo-measurements more so in females than males. Also the relationship of the adult BP measurements with corresponding childhood biological parameters was stronger than the relationship for adult Echo-measurements.
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Moreno, Betancur Margarita. « Regression modeling with missing outcomes : competing risks and longitudinal data ». Thesis, Paris 11, 2013. http://www.theses.fr/2013PA11T076/document.

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Les données manquantes sont fréquentes dans les études médicales. Dans les modèles de régression, les réponses manquantes limitent notre capacité à faire des inférences sur les effets des covariables décrivant la distribution de la totalité des réponses prévues sur laquelle porte l'intérêt médical. Outre la perte de précision, toute inférence statistique requière qu'une hypothèse sur le mécanisme de manquement soit vérifiée. Rubin (1976, Biometrika, 63:581-592) a appelé le mécanisme de manquement MAR (pour les sigles en anglais de « manquant au hasard ») si la probabilité qu'une réponse soit manquante ne dépend pas des réponses manquantes conditionnellement aux données observées, et MNAR (pour les sigles en anglais de « manquant non au hasard ») autrement. Cette distinction a des implications importantes pour la modélisation, mais en général il n'est pas possible de déterminer si le mécanisme de manquement est MAR ou MNAR à partir des données disponibles. Par conséquent, il est indispensable d'effectuer des analyses de sensibilité pour évaluer la robustesse des inférences aux hypothèses de manquement.Pour les données multivariées incomplètes, c'est-à-dire, lorsque l'intérêt porte sur un vecteur de réponses dont certaines composantes peuvent être manquantes, plusieurs méthodes de modélisation sous l'hypothèse MAR et, dans une moindre mesure, sous l'hypothèse MNAR ont été proposées. En revanche, le développement de méthodes pour effectuer des analyses de sensibilité est un domaine actif de recherche. Le premier objectif de cette thèse était de développer une méthode d'analyse de sensibilité pour les données longitudinales continues avec des sorties d'étude, c'est-à-dire, pour les réponses continues, ordonnées dans le temps, qui sont complètement observées pour chaque individu jusqu'à la fin de l'étude ou jusqu'à ce qu'il sorte définitivement de l'étude. Dans l'approche proposée, on évalue les inférences obtenues à partir d'une famille de modèles MNAR dits « de mélange de profils », indexés par un paramètre qui quantifie le départ par rapport à l'hypothèse MAR. La méthode a été motivée par un essai clinique étudiant un traitement pour le trouble du maintien du sommeil, durant lequel 22% des individus sont sortis de l'étude avant la fin.Le second objectif était de développer des méthodes pour la modélisation de risques concurrents avec des causes d'évènement manquantes en s'appuyant sur la théorie existante pour les données multivariées incomplètes. Les risques concurrents apparaissent comme une extension du modèle standard de l'analyse de survie où l'on distingue le type d'évènement ou la cause l'ayant entrainé. Les méthodes pour modéliser le risque cause-spécifique et la fonction d'incidence cumulée supposent en général que la cause d'évènement est connue pour tous les individus, ce qui n'est pas toujours le cas. Certains auteurs ont proposé des méthodes de régression gérant les causes manquantes sous l'hypothèse MAR, notamment pour la modélisation semi-paramétrique du risque. Mais d'autres modèles n'ont pas été considérés, de même que la modélisation sous MNAR et les analyses de sensibilité. Nous proposons des estimateurs pondérés et une approche par imputation multiple pour la modélisation semi-paramétrique de l'incidence cumulée sous l'hypothèse MAR. En outre, nous étudions une approche par maximum de vraisemblance pour la modélisation paramétrique du risque et de l'incidence sous MAR. Enfin, nous considérons des modèles de mélange de profils dans le contexte des analyses de sensibilité. Un essai clinique étudiant un traitement pour le cancer du sein de stade II avec 23% des causes de décès manquantes sert à illustrer les méthodes proposées
Missing data are a common occurrence in medical studies. In regression modeling, missing outcomes limit our capability to draw inferences about the covariate effects of medical interest, which are those describing the distribution of the entire set of planned outcomes. In addition to losing precision, the validity of any method used to draw inferences from the observed data will require that some assumption about the mechanism leading to missing outcomes holds. Rubin (1976, Biometrika, 63:581-592) called the missingness mechanism MAR (for “missing at random”) if the probability of an outcome being missing does not depend on missing outcomes when conditioning on the observed data, and MNAR (for “missing not at random”) otherwise. This distinction has important implications regarding the modeling requirements to draw valid inferences from the available data, but generally it is not possible to assess from these data whether the missingness mechanism is MAR or MNAR. Hence, sensitivity analyses should be routinely performed to assess the robustness of inferences to assumptions about the missingness mechanism. In the field of incomplete multivariate data, in which the outcomes are gathered in a vector for which some components may be missing, MAR methods are widely available and increasingly used, and several MNAR modeling strategies have also been proposed. On the other hand, although some sensitivity analysis methodology has been developed, this is still an active area of research. The first aim of this dissertation was to develop a sensitivity analysis approach for continuous longitudinal data with drop-outs, that is, continuous outcomes that are ordered in time and completely observed for each individual up to a certain time-point, at which the individual drops-out so that all the subsequent outcomes are missing. The proposed approach consists in assessing the inferences obtained across a family of MNAR pattern-mixture models indexed by a so-called sensitivity parameter that quantifies the departure from MAR. The approach was prompted by a randomized clinical trial investigating the benefits of a treatment for sleep-maintenance insomnia, from which 22% of the individuals had dropped-out before the study end. The second aim was to build on the existing theory for incomplete multivariate data to develop methods for competing risks data with missing causes of failure. The competing risks model is an extension of the standard survival analysis model in which failures from different causes are distinguished. Strategies for modeling competing risks functionals, such as the cause-specific hazards (CSH) and the cumulative incidence function (CIF), generally assume that the cause of failure is known for all patients, but this is not always the case. Some methods for regression with missing causes under the MAR assumption have already been proposed, especially for semi-parametric modeling of the CSH. But other useful models have received little attention, and MNAR modeling and sensitivity analysis approaches have never been considered in this setting. We propose a general framework for semi-parametric regression modeling of the CIF under MAR using inverse probability weighting and multiple imputation ideas. Also under MAR, we propose a direct likelihood approach for parametric regression modeling of the CSH and the CIF. Furthermore, we consider MNAR pattern-mixture models in the context of sensitivity analyses. In the competing risks literature, a starting point for methodological developments for handling missing causes was a stage II breast cancer randomized clinical trial in which 23% of the deceased women had missing cause of death. We use these data to illustrate the practical value of the proposed approaches
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Stålnacke, Johanna. « Rough beginnings : Executive function in adolescents and young adults after preterm birth and repeat antenatal corticosteroid treatment ». Doctoral thesis, Stockholms universitet, Psykologiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-106798.

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This thesis investigates long-term cognitive outcome in two cohorts of adolescents and young adults exposed to stressors during the perinatal period: one group born preterm (<37 weeks of gestation and birth weight <1,500 g); one group exposed to two or more courses of antenatal corticosteroids (ACS), to stimulate lung maturation in the face of threatening preterm birth. In fetal life the brain undergoes dramatic growth, and a disruption to the early establishment of functional neural networks may interrupt development in ways that are difficult to predict. Executive function refers to a set of cognitive processes that are important for purposeful regulation of thought, emotion, and behavior, and even a subtle depreciation may influence overall functioning. Study I investigated the stability of executive function development after preterm birth. Executive functions were differentiated into working memory and cognitive flexibility. Both components were highly stable from preschool age to late adolescence. In Study II, we identified subgroups within the group of children born preterm with respect to cognitive profiles at 5½ and 18 years, and identified longitudinal streams. Outcome after preterm birth was diverse, and insufficiently predicted by perinatal and family factors. Individuals performing at low levels at 5½ years were unlikely to improve over time, while a group of individuals performing at or above norm at 5½ years had improved their performance relative to term-born peers by age 18. Studies I and II pointed to the need for developmental monitoring of those at risk, prior to formal schooling. Study III investigated long-term cognitive outcome after repeat ACS treatment. The study did not provide support for the concern that repeat ACS exposure will have an adverse impact on cognitive function later in life. In sum, exposure to perinatal stressors resulted in great variation in outcome. However, for many, their rough beginnings had not left a lasting mark.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 1: Submitted.

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46

Leonard, Kenneth Paul. « Influence of age on lean body mass, grip strength, and sensory motor function in young and old F344 rats a cross sectional and longitudinal approach / ». Tallahassee, Fla. : Florida State University, 2009. http://purl.fcla.edu/fsu/lib/digcoll/undergraduate/honors-theses/329860.

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Thesis (Honors paper)--Florida State University, 2009.
Advisor: Dr. Jeong-Su Kim, Florida State University, College of Human Sciences, Dept. of Nutrition, Food and Exercise Sciences. Includes bibliographical references.
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Lawrence, Catherine L. « The impact of chemotherapy for breast cancer on managing daily tasks : a longitudinal study of cognitive, psychosocial and safety outcomes in the home and workplace ». Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/12119.

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BACKGROUND. Breast cancer is the most common type of cancer in women in the UK and is often treated with chemotherapy. Psychosocial side effects (anxiety, depression and fatigue) and cognitive side effects (memory and concentration difficulties) are frequently reported by breast cancer patients. Following recent advances in screening and treatment technology for the disease, survivorship rates have increased. Therefore, women are able to continue or resume their daily tasks during and following treatment. The impact of chemotherapy-related psychological side effects on quality of life and work ability are documented, however the impact on safety outcomes has currently been overlooked in this patient population. Evidence from other research fields suggests that anxiety, depression, fatigue and cognitive difficulties are associated with increased risk of accidents and injuries. OBJECTIVES. This research provides longitudinal self-report data on psychosocial well-being, cognitive function, quality of life, work ability and accident frequency outcomes. METHOD. A mixed-methods, prospective, longitudinal approach was employed. Breast cancer patients about to undergo chemotherapy treatment (n = 60) completed questionnaires at pre-treatment baseline, and again four months (follow-up time 1), eight months (follow-up time 2), and twelve months (follow-up time 3) later. A treatment control group of breast cancer patients receiving radiotherapy (n = 56), and an age-matched healthy control group (n = 58) were assessed at comparable intervals. In addition, a subsample of participants from the chemotherapy group (n = 11), radiotherapy group (n = 6), and healthy control group (n = 15) kept personal solicited diaries for a four-month period to capture the lived experience of managing daily tasks. The diary data were examined using thematic analysis. The combination of the quantitative and qualitative approaches added breadth and depth to the study with the aim of obtaining a realistic and comprehensive understanding of the impact of chemotherapy for breast cancer on patients daily lives. RESULTS. Chemotherapy patients reported a subtle decline in psychosocial well-being, cognitive function and quality of life, and encountered more accidents, particularly at mid-chemotherapy. CONCLUSION. It is important that healthcare professionals, breast cancer patients, relatives and employers are aware of the temporal fluctuations associated with chemotherapy-related side effects, particularly potential safety outcomes. Interventions could be developed to help patients manage their daily tasks in the home and in the workplace safely.
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Noal, Ricardo Bica. « Estado nutricional, asma e função pulmonar em adolescentes coorte de nascimentos de 1993, Pelotas RS ». Universidade Federal de Pelotas, 2011. http://repositorio.ufpel.edu.br/handle/ri/1979.

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Obesity, as well as impaired lung function, is associated with significant morbidity and mortality. Few studies have evaluated the effect of adiposity on lung function in adolescents. This study was conducted to evaluate the effect of body mass index and sum of skinfolds (triceps and subscapular) on pulmonary function (forced expiratory volume in one second and forced vital capacity) of adolescents in the study there longitudinal live births in 1993, Pelotas - Brazil. Teenagers aged between 14 and 15 years were interviewed (n = 4349), follow-up rate of 85.7% of the original cohort, measured (n = 4110) and their lung function measured (n = 4006). It was observed through a cross-sectional analysis, after controlling for confounding factors during the gestational period, the body mass index presents. Overall direct effect on lung function while the sum of skinfolds opposite effect. The longitudinal analysis allowed us to observe that adolescents, regardless of sex, which remained in the lower tertiles of body mass index during follow-up had lower levels of lung function than those who remained in the middle tercile. The boys who remained in the highest tertile of skinfold thickness had lower lung function values. These findings suggest that low body mass index and the large sum of skinfold thicknesses have negative impact on lung function in adolescents.
A obesidade, assim como a redução da função pulmonar, esta associada à morbidade e mortalidade. Poucos estudos avaliaram o efeito da adiposidade sobre a função pulmonar em adolescentes. Esse estudo foi realizado com objetivo de avaliar o efeito do índice de massa corporal e do somatório das pregas cutâneas (tricipital e subescapular) sobre a função pulmonar (volume expiratório forçado no primeiro segundo e capacidade vital forçada) de adolescentes pertencentes ai estudo longitudinal dos nascidos vivos em 1993, Pelotas Brasil. Os adolescentes com idade entre 14 e 15 anos foram entrevistados (n=4349), taxa de acompanhamento de 85,7% da coorte original, medidos (n=4110) e sua função pulmonar avaliada (n=4006). Observou-se através de uma análise transversal que, após controle para fatores de confusão desde o período gestacional, o índice de massa corporal apresenta de maneira geral efeito direto sobre a função pulmonar ao passo que o somatório de pregas cutâneas efeito inverso. A análise longitudinal permitiu observar que os adolescentes, independentemente do sexo, que permaneceram nos menores tercis do índice de massa corporal durante o acompanhamento apresentaram menores valores de função pulmonar em relação aos que permaneceram no tercil médio. Os meninos que permaneceram no maior tercil de pregas cutâneas apresentaram menores valores de função pulmonar. Esses achados sugerem que o baixo índice de massa corporal e o elevado somatório de pregas cutâneas apresentam impacto negativo sobre a função pulmonar de adolescentes.
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Alnaji, Lulah A. « Generalized Estimating Equations for Mixed Models ». Bowling Green State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1530292694012892.

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Silva, Keyte Guedes da. « Efeitos de um treinamento com o Nintendo® Wii sobre o equilíbrio postural e funções executivas de idosos saudáveis, um estudo clínico longitudinal, controlado e aleatorizado ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/47/47135/tde-30072013-122720/.

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O objetivo do presente estudo foi comparar os efeitos obtidos por meio de um treinamento fisioterapêutico associado a jogos do Nintendo® Wii Fit, com um treinamento fisioterapêutico convencional sobre o equilíbrio e a cognição de idosos saudáveis. Trata-se de um ensaio clínico controlado, aleatorizado e cego realizado no Departamento de Fonoaudiologia, Fisioterapia e Terapia Ocupacional da Universidade de São Paulo. Participaram do estudo 32 idosos saudáveis da comunidade que foram aleatorizados em grupos controle e experimental, 16 em cada grupo. Todos os sujeitos foram submetidos a 14 sessões individuais de treinamento, duas vezes por semana, por sete semanas. Cada sessão foi composta de 30 minutos de exercícios globais, incluindo alongamento e fortalecimento muscular e mobilidade axial. Após os exercícios globais, os grupos realizaram mais 30 minutos de exercícios de equilíbrio, sendo que o grupo experimental realizou o treinamento associados aos jogos do Nintendo® Wii Fit, e o grupo controle exercícios de equilíbrio convencional. As principais medidas do estudo foram: (1) Mini-Balance Evaluation System (Mini-BEST) Test e (2) Unipedal Stance Test para avaliação do equilíbrio; (3) Escala Internacional de Eficácia de Quedas (FES-I) para avaliação da autoconfiança no equilíbrio; (4) Escala de Atividade de Vida Diária (EAVD) para avaliar a autonomia nas atividades de vida diária; e (5) Avaliação Cognitiva Montreal (MoCA) para avaliação cognitiva. A análise estatística foi realizada por meio da ANOVA one-way e para os efeitos que alcançaram nível de significância, foi realizado o Pós-hoc teste de Tukey-Kramer para a verificação de possíveis diferenças entre os grupos e avaliações realizadas antes, depois e após 60 dias do final do treinamento. Os resultados mostraram que houve uma interação estatisticamente significativa entre os fatores avaliação e grupo confirmados pelo Pós-hoc teste de Tukey, mostrando que o treinamento com o videogame proporcionou melhora significativa nas medidas avaliadas depois treinamento, sem perdas significativas na avaliação após 60 dias. Assim, o treinamento fisioterapêutico associados aos jogos do Nintendo® Wii Fit mostrou-se mais eficiente para melhorar o equilíbrio, cognição e funcionalidade de idosos saudáveis em comparação ao treinamento convencional atualmente preconizado, o que indica que o 9 videogame pode ser uma ferramenta complementar útil ao tratamento fisioterapêutico voltado para a prevenção precoce das alterações cognitivas e motoras em idosos
The aim of this study was to compare the effects obtained through a physical therapy training associated with games Nintendo® Wii Fit with physical therapy training alone on balance and cognition in older adults. It was a prospective, controlled, single blinded randomized clinical trial performed at Speech Therapy, Physiotherapy and Occupational Department of São Paulo University. 32 healthy older adults in the community participated of this study and were randomized in control and experimental groups, 16 each one. All subjects performed 14 individual training sessions, twice a week, for seven weeks. Each session was composed of a 30 minutes global exercises series including stretching, muscles strengthen and axial mobility exercises. After the exercises global, both groups performed more 30 minutes of balance training: the experimental group performed the balance training associated with games of Nintendo® Wii Fit, and the control group standard balance exercises. The main outcome measures were: (1) Mini-Balance Evaluation System (Mini-BEST); (2) Unipedal Stance Test; (3) Efficacy Scale International Falls (FES-I); (4) Scale of Activities of Daily Living (EAVD) and (5) Montreal Cognitive Assessment (MoCA). Statistical analysis was done by one-way ANOVA in order to assess possible differences among the analyzed variables. Results showed statistically significant improvement in the measures evaluated in the experimental group, without any significant changes after 60 days. Wii Fit training appears to improve balance, cognition and functionality of healthy elderly compared to conventional training preconized, which indicates that videogame mat be a useful additional tool to physical therapy toward the early prevention of cognitive and motor changes in the elderly
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