Development and Evaluation of Interactive Courseware for Visualization of Graph Data Structure and Algorithms

The primary goal of this dissertation was to develop and pilot test interactive, multimedia courseware which would facilitate learning the abstract structures, operations, and concepts associated with graph and network data structures in Computer Science. Learning objectives and prerequisites are presented in an introduction section of the courseware and a variety of learning activities are provided including tutorials, animated demonstrations, interactive laboratory sessions, and self-tests. Courseware development incorporated principles and practices from software engineering, instructional design, and cognitive learning theories. Implementation utilized an easy-to-use authoring tool, NeoBook Professional (1994), to create the overall framework and the user interfaces, and Microsoft QuickBASIC 4.5 (1990) to program the interactive animated demonstrations and laboratory exercises. A major emphasis of the courseware is the use of simple interactive, animated displays to demonstrate the step-by-step operation of graph and network algorithms such as depth-first traversal, breadth-first traversal, shortest path, minimum sparring tree and topological ordering

Steeper Iris Conicity Is Related to a Shallower Anterior Chamber: The Gutenberg Health Study

Purpose. To report the distribution of iris conicity (steepness of the iris cone), investigate associated factors, and test whether pseudophakia allows the iris to sink back. Methods. A population-based cross-sectional study was carried out. Ophthalmological examination including objective refraction, biometry, noncontact tonometry, and Scheimpflug imaging (Pentacam®, Oculus) was performed including automated measurement of iris conicity. 3708 phakic subjects, 144 subjects with bilateral and 39 subjects with unilateral pseudophakia were included. Multivariable analyses were carried out to determine independently associated systemic and ocular factors for iris conicity in phakic eyes. Results. Mean iris conicity was 8.28° ± 3.29° (right eyes). Statistical analysis revealed associations between steeper iris conicity and shallower anterior chamber depth, thicker human lens and higher corneal power in multivariable analysis, while older age was related to a flatter iris conicity. Refraction, axial length, central corneal thickness, pupil diameter, and intraocular pressure were not associated with iris conicity. Pseudophakia resulted in a 5.82° flatter iris conicity than in the fellow phakic eyes. Conclusions. Associations indicate a correlation between iris conicity with risk factors for angle-closure, namely, shallower anterior chamber depth and thicker human lens. In pseudophakic eyes, iris conicity is significantly lower, indicating that cataract surgery flattens the iris

Prevalence of depression and anxiety among participants with glaucoma in a population-based cohort study : the Gutenberg Health Study

Background To investigate the prevalence of depression and anxiety among subjects with self-reported glaucoma and the association between self-reported glaucoma and depression respectively anxiety in a European cohort. Methods A study sample of 14,657 participants aged 35 to 74 years was investigated in a population-based cohort study. All participants reported presence or absence of glaucoma. Ophthalmological examinations were carried out in all participants and demographic and disease related information were obtained by interview. Depression was assessed with the Patient Health Questionnaire (PHQ-9), and generalized anxiety with the two screening items (GAD-2) of the short form of the GAD-7 (Generalized Anxiety Disorder-7 Scale). Prevalence of depression and generalized anxiety were investigated for subjects with and without self-reported glaucoma. Logistic regression analyses with depression, respectively anxiety as dependent variable and self-reported glaucoma as independent variable were conducted and adjusted for socio-demographic factors, systemic comorbidities (arterial hypertension, myocardial infarction, stroke, diabetes mellitus, chronic obstructive pulmonary disease, cancer), ocular diseases (cataract, macular degeneration, corneal diseases, diabetic retinopathy), visual acuity, intraocular pressure, antiglaucoma eye drops (sympathomimetics, parasympathomimetics, carbonic anhydrase inhibitors, beta-blockers, prostaglandins) and general health status. Results 293 participants (49.5% female) reported having glaucoma. Prevalence of depression among participants with and without self-reported glaucoma was 6.6% (95%-CI 4.1–10.3) respectively 7.7% (95%-CI 7.3–8.2), and for anxiety 5.3% (95%-CI 3.1–8.7) respectively 6.6% (95%-CI 6.2–7.1). Glaucoma was not associated with depression (Odds ratio 1.10, 95%-CI 0.50–2.38, p = 0.80) or anxiety (1.48, 95%-CI 0.63–3.30, p = 0.35) after adjustment for socio-demographic factors, ocular/systemic diseases, ocular parameters, antiglaucoma drugs and general health status. A restriction to self-reported glaucoma cases either taking topical antiglaucoma medications or having a history of glaucoma surgery did not alter the result. Conclusions This is the first study analyzing both depression and anxiety among glaucoma patients in a European cohort. Subjects with and without self-reported glaucoma had a similar prevalence of depression and anxiety in our population-based sample. Self-reported glaucoma was not associated with depression or anxiety. A lack of a burden of depressive symptoms may result from recruitment from a population-based sample as compared to previous study groups predominantly recruited from tertiary care hospitals

No evidence for an association of plasma homocysteine levels and refractive error - Results from the population-based Gutenberg Health Study (GHS)

Purpose There is a strong association between severe hyperhomocysteinemia and myopia. Thus we studied the hypothesis that even moderately increased levels of homocysteine (Hcy) might be a potentially treatable risk factor for myopia. Methods The Gutenberg Health Study (GHS) is a population-based, prospective, observational cohort study in Germany, including 15,010 participants aged between 35 and 74 at recruitment. The baseline examination was conducted from 2007-2012. Refraction was measured using autorefraction (HARK 599, Carl Zeiss AG, Jena, Germany). Hcy was measured by an immunoassay. We included only phakic participants without a history of corneal surgery or corneal laser treatment. We used linear regression models to evaluate the potential association between Hcy and refraction at baseline, and between Hcy and change in refraction between baseline and 5-year-follow-up examination. We used generalized estimating equation models to account for the correlation between fellow eyes. Results We included 13,749 participants, categorized as having no myopia (spherical equivalent > -0.75 D, 65.2%), low myopia (-0.75 D-2.75 D, 21.5%), moderate myopia (-3.00 D- 5.75 D, 9.8%) and high myopia (≤ -6

Challenge Accepted! a Critical Reflection on How to Perform a Health Survey Among University Students—An Example of the Healthy Campus Mainz Project

Background: Universities represent an important setting of everyday life for health promotion. The Healthy Campus Mainz project aims to develop an evidence-based and comprehensive student health management program covering physical, mental, and social health promotion. Hence, an initial health survey was performed in order to identify the students' health concerns and resources. Up until now, it remains unclear which topics to choose in a health survey among university students and which strategies can be recommended to receive an acceptable response rate or representative student sample within a university setting. The present paper contributes to the call for the present research topic “Public Health Promotion in University Students” by describing methods for health assessment. Therefore, the current paper aims to give an empirical example on how to perform a health survey among university students, focusing on (1) choosing topics for the survey and (2) methodological considerations of how to reach the target population.Methods: An online questionnaire including around 270 items was developed covering a comprehensive set of health topics. Participants were recruited via the university email. Mixed channels for survey promotion, such as lecture visits and social media, were used, accompanied by different monetary and non-monetary incentives. Descriptive analyses were performed to describe the sample.Results: A total of 5,006 participants (out of 31,213 registered students) viewed the first page of the questionnaire; of whom, 4,714 continued further. After a manual data cleaning according to the predefined criteria, the final sample was 4,351, demonstrating a response rate of 13.9%. Students from different study disciplines participated. However, some study disciplines showed a low participation rate, hence, making the results not free from some bias.Discussion: This survey is exceptional as it integrates a great variety of health aspects. The incentive strategy demonstrated promising results. Future research should try to improve target-group-specific recruitment strategies for the traditionally underrepresented groups, such as males and specific study disciplines. This would not only include advancing marketing strategies, but also refining the incentive strategy

The impact of pseudophakia on vision-related quality of life in the general population - The Gutenberg Health Study.

Cataract surgery is the most frequently performed surgical procedure worldwide. We aim to determine the prevalence of having implanted an artificial lens (pseudophakia) and of no lens (aphakia) and to compare visual function.As part of the Gutenberg Health study, a population-based cross-sectional study was conducted in Germany. An ophthalmological examination including slit-lamp examination was conducted. Prevalence including 95% confidential intervals were calculated and analyses were conducted for systemic and ocular associated factors with pseudophakia using multivariable logistic regression models. Vision-related quality of life was assessed using a standardized questionnaire and Rasch transformation.14,696 people were included. Of these, 1.55% [1.36%-1.77%] had unilateral pseudophakia and 3.08% [2.81%-3.37%] had bilateral pseudophakia. Unilateral aphakia was present in 21 people and bilateral aphakia in 2 people. Pseudophakia was independently associated with age, higher body weight and lower body height, diabetes and smoking. Vision-related quality of life values were similar for those with bilateral phakia and pseudophakia but were lower for those with unilateral pseudophakia.The pseudophakia status is related to several cardiovascular risk factors, indicating a relationship to an aging effect that causes premature lens opacification. Bilateral pseudophakia can almost imitate the physiological condition of phakia except for the need to use glasses

The impact of pseudophakia on vision-related quality of life in the general population -The Gutenberg Health Study

ABSTRACT Cataract surgery is the most frequently performed surgical procedure worldwide. We aim to determine the prevalence of having implanted an artificial lens (pseudophakia) and of no lens (aphakia) and to compare visual function. As part of the Gutenberg Health study, a population-based cross-sectional study was conducted in Germany. An ophthalmological examination including slit-lamp examination was conducted. Prevalence including 95% confidential intervals were calculated and analyses were conducted for systemic and ocular associated factors with pseudophakia using multivariable logistic regression models. Vision-related quality of life was assessed using a standardized questionnaire and Rasch transformation. 14,696 people were included. Of these, 1.55% [1.36%-1.77%] had unilateral pseudophakia and 3.08% [2.81%-3.37%] had bilateral pseudophakia. Unilateral aphakia was present in 21 people and bilateral aphakia in 2 people. Pseudophakia was independently associated with age, higher body weight and lower body height, diabetes and smoking. Vision-related quality of life values were similar for those with bilateral phakia and pseudophakia but were lower for those with unilateral pseudophakia. The pseudophakia status is related to several cardiovascular risk factors, indicating a relationship to an aging effect that causes premature lens opacification. Bilateral pseudophakia can almost imitate the physiological condition of phakia except for the need to use glasses

Cross-Sectional Associations between Homoarginine, Intermediate Phenotypes, and Atrial Fibrillation in the CommunityThe Gutenberg Health Study

Homoarginine has come into the focus of interest as a biomarker for cardiovascular disease. Atrial fibrillation (AF) causes a substantial increase in morbidity and mortality. Whether circulating homoarginine is associated with occurrence or persistence of AF and may serve as a new predictive biomarker remains unknown. We measured plasma levels of homoarginine in the population-based Gutenberg health study (3761 patients included, of them 51.7% males), mean age 55.6 +/- 10.9 years-old. Associations between homoarginine and intermediate electrocardiographic and echocardiographic phenotypes and manifest AF were examined. Patients with AF (124 patients, of them 73.4% males) had a mean age 64.8 +/- 8.6 years-old compared to a mean age of 55.3 +/- 10.9 in the population without AF (p-value < 0.001) and showed a less beneficial risk factor profile. The median homoarginine levels in individuals with and without AF were 1.9 mol/L (interquartile range (IQR) 1.5-2.5) and 2.0 mol/L (IQR 1.5-2.5), respectively, p = 0.56. In multivariable-adjusted regression analyses homoarginine was not statistically significantly related to electrocardiographic variables. Among echocardiographic variables beta per standard deviation increase was -0.12 (95% confidence interval (CI) -0.23-(-0.02);p = 0.024) for left atrial area and -0.01 (95% CI -0.02-(-0.003);p = 0.013) for E/A ratio. The odds ratio between homoarginine and AF was 0.91 (95% CI 0.70-1.16;p = 0.45). In our large, population-based cross-sectional study, we did not find statistically significant correlations between lower homoarginine levels and occurrence or persistence of AF or most standard electrocardiographic phenotypes, but some moderate inverse associations with echocardiographic left atrial size and E/A. Homoarginine may not represent a strong biomarker to identify individuals at increased risk for AF. Further investigations will be needed to elucidate the role of homoarginine and cardiac function

Gender Differences and the Impact of Partnership and Children on Quality of Life During the COVID-19 Pandemic

Objectives: The COVID-19 pandemic and its protective measures have changed the daily lives of families and may have affected quality of life (QoL). The aim of this study was to analyze gender differences in QoL and to examine individuals living in different partnership and family constellations.Methods: Data from the Gutenberg COVID-19 cohort study (N = 10,250) with two measurement time points during the pandemic (2020 and 2021) were used. QoL was assessed using the EUROHIS-QOL questionnaire. Descriptive analyses and autoregressive regressions were performed.Results: Women reported lower QoL than men, and QoL was significantly lower at the second measurement time point in both men and women. Older age, male gender, no migration background, and higher socioeconomic status, as well as partnership and children (especially in men), were protective factors for QoL. Women living with children under 14 and single mothers reported significantly lower QoL.Conclusion: Partnership and family were protective factors for QoL. However, women with young children and single mothers are vulnerable groups for lower QoL. Support is especially needed for women with young children

Noise annoyance and risk of prevalent and incident atrial fibrillation–A sex-specific analysis

BackgroundWhile chronic exposure to high levels of noise was demonstrated to increase the risk of various cardiovascular diseases, the association between noise annoyance and risk of cardiovascular disease remains still inconsistent. Recently, we showed that noise annoyance is associated with prevalent atrial fibrillation in the general population. However, the association between noise annoyance and risk of incident atrial fibrillation as well as potential sex-differences remain still elusive.Methods and results15,010 subjects from a German population-based cohort were examined at baseline (2007 to 2012) and follow-up five years later (2012 to 2017) to investigative the association between noise annoyance due to multiple sources and prevalent and incident atrial fibrillation. After multivariable adjustment, the results from logistic regression analyses revealed overall consistent and positive associations between noise annoyance and prevalent and incident atrial fibrillation in men, whereas this association was weaker in women, in particular with respect to incident atrial fibrillation. For instance, industrial noise annoyance was associated with 21% (95% confidence interval (CI) 9–34%) and 18% (8–29%) higher odds of prevalent atrial fibrillation in men and women, respectively. In prospective analysis, this association remained stable in men (odds ratio (OR) 1.25, 1.07–1.44), while in women no association was observed (OR 1.03, 0.89–1.18).ConclusionsThe findings suggest that noise annoyance can increase the risk of incident atrial fibrillation in a large population-based cohort and that men may be more sensitive to the adverse effects of noise annoyance with regard to the risk of atrial fibrillation