32 research outputs found
Nonductal primary tumours of the pancreas
No full textVon 1983 - 1999 wurden in der Chirurgischen Klinik des Klinikums rechts der Isar München 266 Patienten wegen eines Primärtumors des Pankreas behandelt. 69 Tumoren waren nicht-duktalen Ursprungs. Innerhalb des Gruppenkollektivs der nicht-duktalen Tumoren fanden sich 2 größere Untergruppen, die zystischen epithelialen Tumoren und die neuroendokrinen Tumoren. Diese Gruppen wurden hinsichtlich Epidemiologie, Symptomatik, Diagnostik, Therapie und Prognose untersucht. In beiden Gruppen zeigte sich ein erheblicher prognostischer Vorteil gegenüber der Gruppe der duktalen Adenokarzinome des Pankreas.From 1983 to 1999 at the Departement of Surgery, Klinikum rechts der Isar, Technical University, Munich, 266 patients were treated on a primary tumour of the pancreas. 69 tumours were of nonductal origin. Within the collective of nonductal primary tumours there were found 2 major subgroups, the epithelial cystic tumours and the neuroendocrine tumours. These subgroups were investigated for epidemiology, pathology, diagnostics, therapy and prognosis. It resulted a significant prognostic benefit for both subgroups compared with the group of ductal adenocarcinomas
The connection between mental and physical health : investigating the associations between psychosocial well-being, sleep and cardio-metabolic health in European children and adolescents
No full textBackground
The high prevalence of overweight and obesity and related cardio-metabolic disorders such as insulin resistance and hypertension in European children and adolescents is a matter of concern. Aspects of mental health have been suggested to be determinants of cardio-metabolic health and it has been hypothesised that lifestyle factors such as sleep may be part of the underlying mechanism. However, studies in young populations investigating the role of mental health for sleep or cardio-metabolic markers have mainly focussed on a psychopathological view of mental health. Further, studies on the association between sleep and specific cardio-metabolic markers are either limited or suffer from methodological limitations with respect to the measurement of sleep.
Aims
The present cumulative thesis consists of four original papers that aim to shed light on the associations between psychosocial well-being as one aspect of positive mental health and cardio-metabolic markers. A special focus was put on the role of sleep as a potential mediating factor.
Methods
Analyses were carried out based on data of children and adolescents from 8 European countries participating in the IDEFICS/I.Family study. The IDEFICS/I.Family study was set up to identify risk and protective factors for chronic non-communicable diseases and to develop and evaluate a community-based intervention for the prevention of childhood obesity. The data that were used for this thesis were collected during three examination waves with intervals of approximately 2 and 4 years in between them (Wave 1: 2007/2008, Wave 2: 2009/2010, Wave 3: 2013/2014). In 2015, these examination waves were complemented by an in depth examination of a subsample in which children with overweight were overrepresented. The samples on which the analyses for the different papers were based varied in size between 559 and 6,519 subjects depending on the available data for the respective research question.
Psychosocial well-being comprised items on emotional well-being, self-esteem and social relationships. Sleep characteristics included questionnaire-based and objective measurements of sleep duration, sleep disturbances, sleep quality and sleep timing. Cardio-metabolic markers encompassed waist circumference, blood pressure, the homeostasis model assessment for insulin resistance (HOMA-IR), high-density lipoprotein cholesterol (HDL-C) and triglycerides.
Associations were examined applying a variety of statistical methods including multilevel regression analysis, quantile regression and path analysis.
Results
Higher psychosocial well-being was found to be cross-sectionally associated with longer sleep duration and fewer sleep disturbances (N=6,336). However, well-being at the second examination wave did not predict sleep characteristics 4 years later (N=3,379).
Using actigraphy- and sleep diary-derived sleep characteristics (sleep duration, sleep latency, sleep efficiency, bed- and wake time), the following distinct sleep subtypes were identified in a sample of 559 participants from whom detailed information on sleep was collected in 2015: (i) early birds, (ii) short sleep duration, (iii) optimal sleep and (iv) poor sleep quality. Neither sleep subtype nor the single sleep characteristics were found to be statistically significantly associated with body mass index.
In contrast, an analysis conducted in 3,900 children and adolescents participating in the second and third examination wave revealed a cross-sectional inverse association between parent- or self-reported sleep duration and waist circumference. Longer sleep duration was also found to be indirectly associated with lower HOMA-IR through lower waist circumference. This indirect pathway was also observed longitudinally, i.e. longer sleep duration at the second examination wave was indirectly associated with lower HOMA-IR four years later following the pathway through waist circumference at the second and waist circumference at the third examination wave.
After the associations (i) between psychosocial well-being and sleep and (ii) between sleep and cardio-metabolic markers were investigated in-depth, the associations between psychosocial well-being and cardio-metabolic markers considering sleep duration and other lifestyle factors as potential mediators were analysed in one cross-sectional (N=6,519) and one longitudinal path model (N=1,393). Cross-sectionally, higher psychosocial well-being was found to be indirectly associated with (i) lower waist circumference through a healthier lifestyle and with (ii) lower blood pressure, lower HOMA-IR, lower triglycerides and higher HDL-C through both a healthier lifestyle and lower waist circumference. These indirect effects were also shown in the longitudinal model where changes in psychosocial well-being over the 2- and 4-year-intervals, respectively, were investigated in relation to cardio-metabolic markers measured at the 6-year follow-up (third examination wave). Direct associations were observed between higher levels of psychosocial well-being and lower waist circumference, lower HOMA-IR and higher HDL-C independent of potential confounders and mediators. However, direct associations were less consistent across analyses, i.e. they were partially only observed in the cross-sectional or longitudinal analysis.
Discussion and conclusions
The results of the present thesis support the hypothesis that psychosocial well-being may be linked to cardio-metabolic health through sleep and other lifestyle factors in children and adolescents. One strategy to improve cardio-metabolic health of children and adolescents may therefore be to promote psychosocial well-being and a healthy sleep, e.g. through resilience training programs and mindfulness-based interventions. However, because of the scarcity of research more longitudinal studies designed for gaining further knowledge on the temporal relationships between positive mental health, lifestyle factors and cardio-metabolic health are needed
Sleep duration and blood pressure in children: Analysis of the pan-European IDEFICS cohort
No full textThe present study aims to examine the cross-sectional and longitudinal association between self-reported nocturnal sleep duration, blood pressure, and hypertension in European children, aged 2-9.9 years, participating in the IDEFICS project. Blood pressure (BP) and the main anthropometric indices were measured according to standardized procedures. Childhood elevated BP and hypertension were defined according to the European Society of Hypertension Guidelines for children and adolescents. Parents reported lifestyle and socio-demographic data. Nocturnal sleep duration was assessed as part of a parental 24-h recall and categorized as follows: (a) <= 9 hours/night; (b) >9 hours to <= 10 hours/night; (c) >10 hours to <= 11 hours/night; and (d) >11 hours/night. A complete set of variables included in the present analysis was provided by 7974 participants (boys/girls = 4049/3925) at the baseline survey (T0). Of them, 5656 were re-examined 2 years later at follow-up (T1). Children reporting shorter sleep duration at T0 had significantly higher BP values (P for trend < 0.001) compared to those who slept more. Prospective analyses showed that shorter sleep duration at baseline predicted, over the 2-year follow-up, higher increases in systolic blood pressure and diastolic blood pressure, after adjustment for age, sex, country of origin, BMI z-score, parental education, physical activity, screen time, and T0 value of the examined outcome variables (P for trend < 0.001). Our findings reveal that shorter sleep duration is associated with higher BP in childhood, suggesting that sleep may be a potential risk factor for hypertension later in life
Hydrodynamic forces on slender cylinders oscillating transversely in a current
No full textThe study of the hydrodynamic interaction of cables has become more important in recent years since umbilical cables of more than 3000 meters length have been used when photographing the wreck of the HMS Titanic or the Bismarck. Cable vibration can cause distorting of the digital signals being transmitted as well as premature fatigue failure of the cable conductors. The objective of the present study is to describe the hydrodynamic interaction of an element of such a rather vertical cable which is vibrating more or less crosswise in a constant current.offshore engineeringHydraulic EngineeringCivil Engineering and Geoscience
Artificial ground freezing as a construction method for underground spaces in densely built up areas
No full textThe study looked in to de possibilities to construct underground spaces with temporary artificial ground freezing as a construction method. To determine whether soil freezing is a viable option for underground construction in densely built up areas a case study has been performed for the North-South Line in Amsterdam. With the help of current developments found in the field of artificial ground freezing four different options of constructing a station were developed and compared. The most suitable of these options was modelled in Plaxis. To obtain the correct input parameters the processes occurring as a result of a freeze-thaw cycle were studied. Most important processes are the creep behaviour of the frozen soil, heave as a result of formation of ice lenses in low permeable soils and changing soil parameters due to the freeze-thaw cycle. It was concluded that an alternative design for one of the stations of the North-South Line using artificial freezing would be technically feasible. Also the financial aspects of the design were evaluated. Although the freeze design is more expansive then the currently executed design, the freeze design can compete. Costs are not two or three times as much with respect to conventional techniques as is often thought. In complex situations therefore ground freezing is a technique which should be taken in to account!Underground TechnologyGeoscience & EngineeringCivil Engineering and Geoscience
The feasibility of standardization of a mono-pile mooring facility for FSRU's
No full textAs the LNG market continues to grow internationally, Floating Storage and Regasification Units (FSRU’s) have become an increasingly important component as governments and private companies strive for faster, cheaper and more flexible means of re-gasifying. In order to have a FSRU mooring system which is equally fast deliverable, standardization is considered. In this study standardization of the civil structures is investigated for a jetty-type mooring system on exposed locations, more specifically standardization of the breasting dolphins. The considered dolphins consist of a simple steel mono-pile which transfers the mooring loads to the sub-soil and a pile-head which connects the fender to the mono-pile. It was concluded that standardization of the mono-piles is only possible to a certain extent, namely in a conceptual design phase. In this report a standardized work approach is presented regarding the design of the mono-piles. Additionally, multiple pile designs are conceived for varying conditions. In an early design stage, when very little information is available, already some insight can be gained regarding the dimensions and the costs of these piles. In this thesis, also, the pile-head concept is presented which is most suitable for standardization purposes. This is achieved by a Fiber Reinforce Polymers (FRP)-composite, floating structure with a slide-bearing sliding system. The application of composite has some major advantages as it is fatigue resistant, low maintenance, light weighted and corrosion resistant. The form of the pile-head is also optimized for its application so that the fender loads are transferred in the most efficient manner to the mono-pile, while the slide-bearing allows smooth sliding along the pile’s shaft. Next to standardization of the civil structures, the loading conditions are investigated. Since the FSRU is permanently moored at exposed locations, this issue cannot be treated with ‘normal’ mooring of traveling ship, but must be calculated with the aid of numerical software where the relation between the environmental conditions and the load conditions is critical. The application of such software, however, is considered time-consuming for early design stages. An assessment tool is therefore conceived that calculates the design fender loads in a quick and analytical manner. This report shows that this assessment tool can generate rather accurate results, but that its application is limited.Hydraulic EngineeringHydraulic EngineeringCivil Engineering and Geoscience
Primary school students' mental health in Uganda and its association with school violence, connectedness, and school characteristics: a cross-sectional study.
No full textBACKGROUND: Few studies have explored risk factors for poor mental health in Ugandan primary schools. This study investigated whether individual- and contextual-level school-related factors including violence from school staff and other students, connectedness to school and peers, as well as school size and urban/rural location, were associated with mental health difficulties in Ugandan children. We also examined whether associations between violence exposure at school and mental health were mediated by connectedness as well as whether associations were different for boys and girls. METHODS: The analytic sample consisted of 3,565 students from 42 primary schools participating in the Good Schools Study. Data were collected through individual interviews conducted in June and July 2012. Mental health was measured using the Strengths and Difficulties Questionnaire. Multilevel logistic regression was applied to investigate factors associated with mental health difficulties. RESULTS: Experiences of violence from school staff and other students in the past week were strongly associated with mental health difficulties (OR = 1.58, 95 % CI 1.31 to 1.90 and 1.81, 1.47 to 2.23, respectively). Children with a low school connectedness had 1.43 times (1.11 to 1.83) the odds of mental health difficulties compared to those with a high school connectedness. The OR comparing children never feeling close to other students at their school with those always feeling close was 1.86 (1.18 to 2.93). The effect of violence on mental health was not mediated through the connectedness variables. School size was not related to mental health difficulties, but attending an urban school increased the odds of mental health difficulties after accounting for other factors. We did not find evidence that the effect of one or more of the exposures on the outcome differed between boys and girls. CONCLUSIONS: These findings suggest that violence in school and low connectedness to school and peers are independently associated with mental health difficulties and interventions should address both concurrently. Extra support may be needed for students in urban schools. TRIAL REGISTRATION: Clinicaltrials.gov NCT01678846 . Registered 24 August 2012
Economic consequences of German reunification : 12 months after the big bang
No full textThe author discusses how East Germany is faring 12 months after the big bang unification with West Germany. The experience with the German unification to date raises the question whether there would have been alternative and better courses of action. Such options can be considered in three broad areas: (a) the initial conversion rate and, closely connected, wage policies; (b) the wisdom of transferring the economic and legal system of the Federal Republic of Germany in its entirety; and (c) the desirability of the adopted mix of adjustment measures, in particular the trade-off between social assistance, public investment spending, and incentives for private investment. The"big bang"has worked. In Germany's special situation, more gradual approaches would not have worked because it was politically unthinkable to restrict east-west migration. The German unification provides an opportunity to learn a few lessons about the immensity of this task in the best of all circumstances: the take-over by a"big brother"who is ready to lend a hand in the reconstruction task, and willing to foot most of the bill.Banks&Banking Reform,Municipal Financial Management,Governance Indicators,Environmental Economics&Policies,Economic Theory&Research
Children's stress-related reports and stress biomarkers interact in their association with metabolic syndrome risk
No full textThe purpose was to examine the cross-sectional associations of stress-related reports and stress biomarkers with metabolic syndrome (MetS) risk in children while also testing the interaction between stress biomarkers and stress reports. In 353 children (5-10years old, 7.9% overweight/obese), MetS risk was measured by blood pressure, waist circumference, glucose homeostasis, triglycerides, and high-density cholesterol. Stress was measured by stress-related reports (events, emotions, and internalizing/externalizing problems) and two biomarkers: salivary cortisol (total-day and morning output) and heart rate variability (percentage of consecutive normal RR intervals differing more than 50ms and low-to-high-frequency ratio). Cross-sectional regression analyses with z scored total MetS risk as outcome were adjusted for age, sex, and socio-economic status. Only internalizing problems were directly related to a higher MetS risk score (=0.236). Cortisol and heart rate variability were significant moderators: High cortisol morning output resulted in a positive (unfavourable) report-MetS relationship (=0.259-0.552), whereas low percentage of consecutive normal RR intervals differing more than 50ms resulted in a negative (favourable) report-MetS relationship (=-0.298) and low low-to-high-frequency ratio in a positive (unfavourable) report-MetS relationship (=0.478). In conclusion, stress can sometimes be a disadvantageous factor in metabolic health of otherwise healthy children. The cortisol biomarker seems relevant because metabolic risk was highest when stress-related reports were accompanied by high morning cortisol output
Inventory of surveillance systems assessing dietary, physical activity and sedentary behaviours in Europe: a DEDIPAC study
No full textThere is a need for harmonized public health surveillance systems to monitor regional variations and temporal trends of health behaviours and health outcomes and to align policies, action plans and recommendations in terms of healthy diet and physical (in)activity within Europe. We provide an inventory of currently existing surveillance systems assessing diet, physical activity, and sedentary behaviours in Europe as a tool to assist in the identification of gaps and needs and to contribute to the roadmap for an integrated pan-European surveillance system. An inventory questionnaire was completed by representatives of eleven European countries. Eligible surveillance systems were required to meet specific inclusion criteria. First, pre-screening of available surveillance systems in each country was conducted. Second, an in-depth appraisal of the retained surveillance systems complying with the pre-defined requirements was performed. Fifty surveillance systems met the inclusion criteria: six multinational European surveys and forty-four national surveys. Dietary intake and physical activity are the domains predominantly assessed and adults are the most frequently studied age group. Many on-going activities were identified at the national level focussing on adults, but fewer surveillance systems involving vulnerable groups such as infants and pre-school children. Assessment of sedentary and dietary behaviours should be more frequently considered. There is a need for harmonization of surveillance methodologies, indicators and target populations for between-country and over time comparisons. This inventory will serve to feed future discussions within the DEDIPAC-JPI major framework on how to optimize design and identify priorities within surveillance
