Visualizing exploratory factor analysis models

Exploratory factor analysis (EFA) is an important tool in data analyses, particularly in social science. Usually four steps are carried out which contain a large number of options. One important option is the number of factors and the association of variables with a factor. Our tools aim to visualize various models with different numbers in parallel of factors and to analyze which consequences a specific option has.We apply our method to data collected at the School of Business and Economics for evaluation of lectures by students. These data were analyzed by Zhou (2004) and Reichelt (2007).Factor analysis, visualization, questionnaire, evaluation of teaching

Keeping track of worm trackers

C. elegans is used extensively as a model system in the neurosciences due to its well defined nervous system. However, the seeming simplicity of this nervous system in anatomical structure and neuronal connectivity, at least compared to higher animals, underlies a rich diversity of behaviors. The usefulness of the worm in genome-wide mutagenesis or RNAi screens, where thousands of strains are assessed for phenotype, emphasizes the need for computational methods for automated parameterization of generated behaviors. In addition, behaviors can be modulated upon external cues like temperature, O2 and CO2 concentrations, mechanosensory and chemosensory inputs. Different machine vision tools have been developed to aid researchers in their efforts to inventory and characterize defined behavioral “outputs”. Here we aim at providing an overview of different worm-tracking packages or video analysis tools designed to quantify different aspects of locomotion such as the occurrence of directional changes (turns, omega bends), curvature of the sinusoidal shape (amplitude, body bend angles) and velocity (speed, backward or forward movement)

Measuring Time Use in Surveys: How Valid Are Time Use Questions in Surveys? Concordance of Survey and Experience Sampling Measures

Since it is still unclear to what extent time allocation retrospectively reported in questionnaires, reflects people's actual behavior, examining the accuracy of responses to time use survey questions is of crucial importance. We analyze the congruence of time use information assessed through retrospective questionnaires and through experience sampling methodology. The sample comprised 433 individuals ranging in age from 14 to 86 years. Participants completed standard survey questions on time allocation. In addition, a mobile-phone based experience sampling technology was used over a period of three weeks to obtain snapshots of, on average, 54 momentary activities in which participants participated while pursuing their normal daily routines. Experience sampling assessments were scheduled six times a day over at least nine days, including workdays, Saturdays, andSundays. Results indicate that the congruence between time allocation assessed with survey questions (i.e. in SOEP) and time allocation assessed with experience sampling methodology depends on the characteristics of the respective activities. Associations between standard survey questions and experience sampling methods are quite substantial for long-lasting and externally structured activities, such as paid work on workdays. Incontrast, associations between survey and experience sampling methods are somewhat weaker, though highly statistically significant, for less externally structured, short-term and infrequent activities, such as errands, housework, and leisure. These moderate and relatively small correlations may indicate either an error-prone estimation of the prevalence of shortterm and infrequent activities by experience sampling or respondents' overrating of sporadic and short activities in survey questions. We conclude that activities with a long duration, such as paid work, can be measured in a satisfactory manner using short survey questions. Futureresearch is necessary to elucidate which method (experience sampling method or survey questions) delivers more reliable and valid measures for shortterm and sporadic activities.Day Reconstruction Methods (DRM) should be included in this future methodological research.Survey methods, experience sampling method, validity, time use, market work, housework, leisure, German Socio-Economic Panel Study, MMAA, SOEP

Integrating Human Satisfaction into the Design Phase – Generating Motivation and Knowledge in Architectural Education

The design of sustainable cities and buildings needs to include thoughts on circumstances influencing human satisfaction be it for thermal, visual, or other dimensions of human perception. While human satisfaction should be regarded as a dimension of sustainability alone, the provision of thermal and visual satisfaction is also a key driving force for energy use in buildings. Research on human perception of the built environment and their interactions with it has a long tradition. At the same time, open research questions especially with respect to the interaction between different dimensions of human perception, e.g. the effect of thermal stimuli on visual perception, are part of the current debate within the research community. In contrast, the amount of scientific knowledge related to human satisfaction transferred to architectural students is low and consequences of their decisions during design studio works for the later occupants are seldom addressed. This paper describes the experiences and results of a teaching experiment, in which architectural students were asked to reflect their own design work finished in a previous year with respect to effects on human satisfaction by means of experimental studies. The research questions raised were a) which design issues can be investigated through experimental studies, and b) to what extent can the motivation of architectural students towards the topic of occupants’ satisfaction be raised. A seminar consisting of three phases was conducted in two consecutive summers. First, students received input related to scientific methods, thermal and visual perception, and had to reflect on one of their previous design works in order to extract research questions and hypotheses. In the second phase, students had to design and conduct a small experimentalstudy related to their research questions. In addition, they had to participate in the experiments organized by their fellow students. In the third phase, the experimental data was analysed and had to be presented together with the reflection of consequences for future design works. The results of this teaching experiment show the huge variety of design issues dealt with in the context of this seminar. Research questions originating from the students were in parts related to cutting edge research questions such as the interaction between different dimensions of perception. From the perspective of a raised motivation, a large number of students showed great interest in the topic, participated with enthusiasm, and evaluated this seminar very high. Limitations have to be seen in the small sample sizes reachable by this seminar approach with many experiments being conducted with less than 10 participants due to limited resources in time and budget, and in the low level of statistical knowledge, which is not part of architectural education

Computed tomographic appearance of urachal adenocarcinomas: review of 25 cases

Twenty-five cases of surgically proven urachal carcinomas were retrospectively reviewed. The radiological archives at the Armed Forces Institute of Pathology were searched for cases of surgically proven urachal carcinomas that had a computed tomographic (CT) scan as a part of their radiologic evaluation. CT images from all cases were evaluated to determine tumor morphology, presence and localization of calcification, extent of bladder invasion and metastases. Tumor size at presentation averaged 6cm. Twenty-one of 25 (84%) were mixed cystic solid lesions and 4/25 (16%) were completely solid. Calcifications were present in 18/25 (72%), with 11 peripherally located, 3 central only and 4 both. Bladder wall invasion was present in 23/25 (92%), but was seen as an intraluminal mass in only 13/25 (52%). The bulk of the mass was extravesicular in 22/25 (88%). Metastases were present in 12/25 (48%). Our series supports observations from other smaller series that a midline, calcified, supravesicular mass is highly suspicious, if not pathognomonic, for urachal carcinom

Age-related differences in stress response: Increase markers for oxidative stress and liver damage after heat stress in aged rats?

Das Altern ist definiert als ein fortschreitender Prozess begleitet von konstanter Abnahme der physiologischen Eigenschaften eines Organismus, der im Laufe der Zeit zu Krankheit und letztendlich unweigerlich zum Tode führt. Als eine der Hauptursachen für den zellulären Alterungsprozess wurde eine erhöhte Zellschädigung durch vermehrten oxidativen Stress entdeckt, die definiert ist als Ungleichgewicht zwischen zunehmender Freisetzung reaktiver Sauerstoffspezies (ROS) und dem Abfall protektiver Antioxidantien. Diese Studie ist ein Bestandteil des über das Bundesministerium für Bildung und Forschung geförderten Verbundprojektes OXISYS und untersucht altersabhängige Zellschäden vor und nach einem zweiphasigen Hitzestressversuch in Serum und Lebergeweben von männlichen Wistar-Ratten in verschiedenen Altersgruppen. Die Kontrollgruppe ohne Hitzestressbehandlung besteht aus jungen (7 Wochen, N = 8), mittelalten (6/7 Monate, N = 10) und alten (23 Monate, N = 10) Ratten. Im Hitzestressversuch wurden mittelalte (7 Monate, N = 22) mit alten (23 Monate, N = 22) Ratten verglichen und die Probenentnahme sowie die Liquidation erfolgte an vier verschiedenen Zeitpunkten (0 h, 2 h, 4 h, 6 h) nach dem zweiten Hitzestress je Altersgruppe. Basierend auf Vorstudien von Zhang et al wurden die generelle Zellschädigung mittels Lactatdehydrogenase (LDH)-Aktivität und die spezifische Leberschädigung zusätzlich anhand der Alaninaminotransferase (ALT)-Aktivität bestimmt. Oxidative Schäden an zellulären Bestandteilen wie Proteinen, DNA und Fetten akkumulieren im Alter und es wurden zwei Endprodukte der Lipidperoxidation, Malondialdehyd (MDA) und 4-Hydroxynonenal (4-HNE) bestimmt, um den Grad des oxidativen Stresses zu verdeutlichen. Ergänzend wurde die Leberzellschädigung durch histologische Beurteilung Hämatoxylin & Eosin eingefärbter Schnitte von Lebergewebe dargestellt. Die Untersuchungen dieser Studie zeigten ein Ausbleiben des erwarteten signifikanten Anstieges der Enzymaktivitäten und Markern der Lipidperoxidation vor und nach Hitzestress in älteren Ratten. Histologisch konnte eine höhere Leberzellschädigung in alten Ratten im Vergleich zu weitgehend normalem Lebergewebe in jungen Ratten gezeigt werden. Kontroverse Ergebnisse im Tiermodell nach Hitzestress könnten eine geringere Beeinträchtigung der Leber im Vergleich zu anderen Organen nahelegen. Besonders aufgrund der hohen Regenerationsfähigkeit der Leber sollte die Möglichkeit einer Präkonditionierung in dieser Untersuchung nach dem ersten Hitzestress in Betracht gezogen werden. Dazu kommt die mögliche Rolle protektiver Antioxidantien, die in weiteren Studien zusätzlich untersucht und ebenfalls miteinbezogen werden sollte. Eine endgültige Entschlüsselung des menschlichen Alterungsprozesses ist weiterhin grundlegender Bestandteil der molekularen Alterungsforschung und weitere Untersuchungen sind notwendig um effektive Gegenmaßnahmen zu entwickeln und dem Menschen ein langes gesundes Leben zu ermöglichen

Does thermal control improve visual satisfaction? Interactions between occupants’ self-perceived control, visual, thermal, and overall satisfaction

Occupants’ satisfaction had been researched independently related to thermal and visual stimuli for many decades showing among others the influence of self-perceived control. Few studies revealed interactions between thermal and visual stimuli affecting occupant satisfaction. In addition, studies including interactions between thermal and visual stimuli are lacking different control scenarios. This study focused on the effects of thermal and visual factors, their interaction, seasonal influences, and the degree of self-perceived control on overall, thermal, and visual satisfaction. A repeated-measures laboratory study with 61 participants running over two years and a total of 986 participant sessions was conducted. Mixed model analyses with overall satisfaction as outcome variable revealed that thermal satisfaction and visual satisfaction are the most important predictors for overall satisfaction with the indoor environment. Self-perceived thermal control served as moderator between thermal satisfaction and overall satisfaction. Season had slight influence on overall satisfaction. Random effects explained the highest amount of variance, indicating that intra- and interindividual differences in the ratings of satisfaction are more prevalent than study condition. Future building design and operation plans aiming at a high level of occupant satisfaction should consider personal control opportunities and take into account the moderating effect of control opportunities in multimodal interactions

Life Course Socioeconomic Conditions and Multimorbidity in Old Age - A Scoping Review.

Multimorbidity disproportionally affects individuals exposed to socioeconomic disadvantage. It is, however, unclear how adverse socioeconomic conditions (SEC) at different periods of the life course predict the occurrence of multimorbidity in later life. In this scoping review, we investigate the association between life course SEC and later-life multimorbidity, and assess to which extent it supports different life course causal models (critical period, sensitive period, accumulation, pathway, or social mobility). We identified four studies (25,209 participants) with the first measure of SEC in childhood (before age 18). In these four studies, childhood SEC was associated with multimorbidity in old age, and the associations were partially or fully attenuated upon adjustment for later-life SEC. These results are consistent with the sensitive period and the pathway models. We identified five studies (91,236 participants) with the first measure of SEC in young adulthood (after age 18), and the associations with multimorbidity in old age as well as the effects of adjustment for later-life SEC differed from one study to the other. Among the nine included studies, none tested the social mobility or the accumulation models. In conclusion, SEC in early life could have an effect on multimorbidity, attenuated at least partly by SEC in adulthood

Toxicological Issues of Nanoparticles Employed in Photocatalysis

A huge amount of different nanomaterials is nowadays on the market used for various specific applications. Some nanomaterials such as TiO2, ZnO as well as several other semiconductors exhibit photocatalytic activity. Hence these materials are used for many applications, e.g., for self-cleaning and antibacterial coatings on different surfaces and for the purification of wastewater where the cleaning can be induced by simple exposure to sunlight. Because of the frequent use of these nanoparticles it is important to investigate the life cycles of these nanostructured materials as well as their environmental impact and their toxicity to animals and humans. This review first gives a short overview about nanotechnology and nanotechnological products as well as about photocatalysis and semiconductors used in this field. We then discuss the need for a new technology named nanotoxicology and the problems occurring when investigating the toxic potential of nanomaterials as well as the life cycle of nanomaterials. Furthermore, we focus on the environmental impact of TiO2 and ZnO nanoparticles including toxic effects to bacteria, water organisms and plants as well as their toxic effects to humans including in vitro and in vivo studies

Qualitätsmanagement in der beruflichen Bildung in Deutschland: ein aktueller Überblick mit dem Schwerpunkt der schulinternen Evaluation

Der folgende Beitrag zeichnet die Verbreitung von QM-Strukturen bzw. QM-Instrumenten im deutschen Berufsschulwesen nach und stellt empirische Studien zur Implementierung und Verstetigung von QM-Komponenten durch die einzelschulischen Akteure "vor Ort" vor. Im Zeitraum von 2009 bis 2015 wurden insgesamt 13 Berliner berufliche Schulen prozessbegleitend untersucht. Der Fokus der Betrachtungen liegt auf dem Bereich der schulinternen Evaluation