Die Wirksamkeit von Tageslichtreplikationen auf die Wissensarbeit

Mehr als 90% eines Tages verbringen Europäer im Durchschnitt innerhalb von Gebäuden. In der Vergangenheit orientierten sich die Empfehlungen für Innenbeleuchtung überwiegend an den visuellen Anforderungen. Wenn man aber von einer evolutionären Anpassung des Menschen an natürliche Lichtbedingungen ausgeht, müsste sich die Nachbildung von natürlichen Lichtbedingungen, die über die visuellen Anforderungen hinausgehen, in der künstlichen Raumbeleuchtung positiv auf Befinden und Leistung auswirken. Diese Arbeit geht der Frage „Welche Eigenschaften des natürlichen Lichts sind wichtig und sollten bei der Innenbeleuchtung nachgebildet werden?“ auf den Grund und leistet mit neuen Erkenntnissen zur Lichtwirkung einen Beitrag zur Wissenschaft. Das zentrale Ziel dieser Arbeit ist die Beantwortung der Frage, ob sich eine technisch realisierte Lichtexposition, welche nach Qualität und Dynamik dem natürlichen Tageslicht ähnlicher ist als die heutige Standardbeleuchtung, positiv auf subjektive Befindlichkeiten und die Leistungsfähigkeit auswirkt. Ob und welche Dynamiken des natürlichen Lichts bei der Innenbeleuchtung nachgebildet werden sollten, um optimale Arbeitsbedingungen bei der Wissensarbeit zu schaffen, wird aus grundlegenden Untersuchungen zu dynamischem Licht abgeleitet. Schwerpunkt der Untersuchungen sind ultradiane Lichtwechsel

Predicting melatonin suppression by light in humans:Unifying photoreceptor-based equivalent daylight illuminances, spectral composition, timing and duration of light exposure

Light‐induced melatonin suppression data from 29 peer‐reviewed publications was analysed by means of a machine‐learning approach to establish which light exposure characteristics (ie photopic illuminance, five α‐opic equivalent daylight illuminances [EDIs], duration and timing of the light exposure, and the dichotomous variables pharmacological pupil dilation and narrowband light source) are the main determinants of melatonin suppression. Melatonin suppression in the data set was dominated by four light exposure characteristics: (1) melanopic EDI, (2) light exposure duration, (3) pupil dilation and (4) S‐cone‐opic EDI. A logistic model was used to evaluate the influence of each of these parameters on the melatonin suppression response. The final logistic model was only based on the first three parameters, since melanopic EDI was the best single (photoreceptor) predictor that was only outperformed by S‐cone‐opic EDI for (photopic) illuminances below 21 lux. This confirms and extends findings on the importance of the metric melanopic EDI for predicting biological effects of light in integrative (human‐centric) lighting applications. The model provides initial and general guidance to lighting practitioners on how to combine spectrum, duration and amount of light exposure when controlling non‐visual responses to light, especially melatonin suppression. The model is a starting tool for developing hypotheses on photoreceptors’ contributions to light's non‐visual responses and helps identifying areas where more data are needed, like on the S‐cone contribution at low illuminances

Cognitive Ergonomics in Virtual Environments: Development of an Intuitive and Appropriate Input Device for Navigating in a Virtual Maze

For patients suffering from mild cognitive impairments, the navigation through a virtual maze should be as intuitive and efficient as possible in order to minimize cognitive and physical strain. This paper discusses the appropriateness of interaction devices for being used for easy navigation tasks. Information gained from human centered evaluation was used to develop an intuitive and ergonomic interaction device. Two experiments examined the usability of tracked interaction devices. Usability problems with the devices are discussed. The findings from the experiments were translated into general design guidance, in addition to specific recommendations. A new device was designed on the basis of these recommendations and its usability was evaluated in a second experiment. The results were used to develop a lightweight interaction device for navigation in the virtual maz

Neurophysiological Age Differences During Task-Performance in a Stereoscopic Virtual Environment

In today's society, there is an increasing number of workplaces in virtual environments (VE). But, there are only a few reports dealing with occupational health issues or age effects. The question arises how VR generally interferes with cognitive processes. This interference might have relevant implications for workability and work-efficiency in virtual environments. Event-related potentials are known to reflect different stages of stimulus reception, evaluation, and response. We have established an electroencephalographic (EEG) monitoring, focussing on event-related potentials (N100; mismatch negativity, i.e., MMN) to obtain access to attention dependent and pre-attentive processing of sensory stimuli applied in VE. The MMN is known to be correlated with the ability of subjects to react to an unexpected event. The aim of the present study was to investigate cognitive responses to distracting auditory stimuli in two different age groups in a virtual environment (VE) and in a real environment ("real reality”), and to compare characteristic neurophysiological response patterns. Data show that stimulus detection as given by the N100 amplitude and latency does not differ in both age groups and task conditions. In contrast, the pre-attentive processing as given by the MMN is altered in the VR such as the non-VR condition in an age-related manner. A relevant finding of the present study was that the age related differences seen in the non-VR condition were not strengthened in V

Stimulation of Cortisol During Mental Task Performance in a Provocative Virtual Environment

Fully immersive and stereoscopic Virtual Environments (VE) represent a powerful multimedia tool for laboratory-based simulations of distinct scenarios including scenarios for evaluating stressful situations resembling reality. Thus far, cortisol secretion as a neuroendocrine parameter of stress has not been evaluated within a Virtual Reality (VR)-based paradigm. In this study 94 healthy volunteers were subjected to a provocative VR-paradigm and a cognitive stress task. Provocative in this context means the VE was designed to provoke physiological reactions (cortisol secretion) within the respective users by purpose. It was tested (a) if a fully dynamic VE as opposed to a static VE can be regarded as a stressor and (b) if such a fully dynamic VE can modify an additional response to a cognitive stressor presented within the VE additionally. Furthermore, possible gender-related impacts on cortisol responses were assessed. A significant cortisol increase was observed only after the combined application of the fully dynamic VE and the cognitive stressor, but not after application of the dynamic VE or the cognitive stressor alone. Cortisol reactivity was greater for men than for women. We conclude that a fully dynamic VE does not affect cortisol secretion per se, but increases cortisol responses to a dual task paradigm that includes performance of a stressful mental task. This provides the basis for the application of VR-based technologies in neuroscientific research, including the assessment of the human Hypothalamus-Pituitary-Adrenal (HPA) axis regulatio

Validation of a new cardiac image fusion software for three-dimensional integration of myocardial perfusion SPECT and stand-alone 64-slice CT angiography

Purpose: Combining the functional information of SPECT myocardial perfusion imaging (SPECT-MPI) and the morphological information of coronary CT angiography (CTA) may allow easier evaluation of the spatial relationship between coronary stenoses and perfusion defects. The aim of the present study was the validation of a novel software solution for three-dimensional (3D) image fusion of SPECT-MPI and CTA. Methods: SPECT-MPI with adenosine stress/rest 99mTc-tetrofosmin was fused with 64-slice CTA in 15 consecutive patients with a single perfusion defect and a single significant coronary artery stenosis (≥50% diameter stenosis). 3D fused SPECT/CT images were analysed by two independent observers with regard to superposition of the stenosed vessel onto the myocardial perfusion defect. Interobserver variability was assessed by recording the X, Y, Z coordinates for the origin of the stenosed coronary artery and the centre of the perfusion defect and measuring the distance between the two landmarks. Results: SPECT-MPI revealed a fixed defect in seven patients, a reversible defect in five patients and a mixed defect in three patients and CTA documented a significant stenosis in the respective subtending coronary artery. 3D fused SPECT/CT images showed a match of coronary lesion and perfusion defect in each patient and the fusion process took less than 15min. Interobserver variability was excellent for landmark detection (r = 1.00 and r = 0.99, p < 0.0001) and very good for the 3D distance between the two landmarks (r = 0.94, p < 0.001). Conclusion: 3D SPECT/CT image fusion is feasible, reproducible and allows correct superposition of SPECT segments onto cardiac CT anatom

Interventions for the treatment of oral cavity and oropharyngeal cancer:chemotherapy

&lt;b&gt;Background:&lt;/b&gt; Oral cavity and oropharyngeal cancers are frequently described as part of a group of oral cancers or head and neck cancer. Treatment of oral cavity cancer is generally surgery followed by radiotherapy, whereas oropharyngeal cancers, which are more likely to be advanced at the time of diagnosis, are managed with radiotherapy or chemoradiation. Surgery for oral cancers can be disfiguring and both surgery and radiotherapy have significant functional side effects, notably impaired ability to eat, drink and talk. The development of new chemotherapy agents, new combinations of agents and changes in the relative timing of surgery, radiotherapy, and chemotherapy treatments may potentially bring about increases in both survival and quality of life for this group of patients.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Objectives:&lt;/b&gt; To determine whether chemotherapy, in addition to radiotherapy and/or surgery for oral cavity and oropharyngeal cancer results in improved survival, disease free survival, progression free survival, locoregional control and reduced recurrence of disease. To determine which regimen and time of administration (induction, concomitant or adjuvant) is associated with better outcomes.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Search strategy:&lt;/b&gt; Electronic searches of the Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE, EMBASE, AMED were undertaken on 28th July 2010. Reference lists of recent reviews and included studies were also searched to identify further trials.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Selection criteria:&lt;/b&gt; Randomised controlled trials where more than 50% of participants had primary tumours in the oral cavity or oropharynx, and which compared the addition of chemotherapy to other treatments such as radiotherapy and/or surgery, or compared two or more chemotherapy regimens or modes of administration, were included.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Data collection and analysis:&lt;/b&gt; Trials which met the inclusion criteria were assessed for risk of bias using six domains: sequence generation, allocation concealment, blinding, completeness of outcome data, selective reporting and other possible sources of bias. Data were extracted using a specially designed form and entered into the characteristics of included studies table and the analysis sections of the review. The proportion of participants in each trial with oral cavity and oropharyngeal cancers are recorded in Additional Table 1.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Main results:&lt;/b&gt; There was no statistically significant improvement in overall survival associated with induction chemotherapy compared to locoregional treatment alone in 25 trials (hazard ratio (HR) of mortality 0.92, 95% confidence interval (CI) 0.84 to 1.00). Post-surgery adjuvant chemotherapy was associated with improved overall survival compared to surgery +/- radiotherapy alone in 10 trials (HR of mortality 0.88, 95% CI 0.79 to 0.99), and there was an additional benefit of adjuvant concomitant chemoradiotherapy compared to radiotherapy in 4 of these trials (HR of mortality 0.84, 95% CI 0.72 to 0.98). Concomitant chemoradiotherapy resulted in improved survival compared to radiotherapy alone in patients whose tumours were considered unresectable in 25 trials (HR of mortality 0.79, 95% CI 0.74 to 0.84). However, the additional toxicity attributable to chemotherapy in the combined regimens remains unquantified.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Authors' conclusions:&lt;/b&gt; Chemotherapy, in addition to radiotherapy and surgery, is associated with improved overall survival in patients with oral cavity and oropharyngeal cancers. Induction chemotherapy is associated with a 9% increase in survival and adjuvant concomitant chemoradiotherapy is associated with a 16% increase in overall survival following surgery. In patients with unresectable tumours, concomitant chemoradiotherapy showed a 22% benefit in overall survival compared with radiotherapy alone.&lt;p&gt;&lt;/p&gt

Distracting people from sources of discomfort in a simulated aircraft environment

BACKGROUND: Comfort is an important factor in the acceptance of transport systems. In 2010 and 2011, the European Commission (EC) put forward its vision for air travel in the year 2050 which envisaged the use of in-flight virtual reality. This paper addressed the EC vision by investigating the effect of virtual environments on comfort. Research has shown that virtual environments can provide entertaining experiences and can be effective distracters from painful experiences. OBJECTIVE: To determine the extent to which a virtual environment could distract people from sources of discomfort. METHODS: Experiments which involved inducing discomfort commonly experienced in-flight (e.g. limited space, noise) in order to determine the extent to which viewing a virtual environment could distract people from discomfort. RESULTS: Virtual environments can fully or partially distract people from sources of discomfort, becoming more effective when they are interesting. They are also more effective at distracting people from discomfort caused by restricted space than noise disturbances. CONCLUSIONS: Virtual environments have the potential to enhance passenger comfort by providing positive distractions from sources of discomfort. Further research is required to understand more fully the reasons why the effect was stronger for one source of discomfort than the other

Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020

We show the distribution of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three genomic nomenclature systems to all sequence data from the World Health Organization European Region available until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation, compare the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2

A Utilisation Focussed and Viable Systems Approach for Evaluating Technology Supported Learning

The paper uses a higher education case study to illustrate a participative theory of change approach to evaluating technology supported learning. The approach is informed by the Viable Systems Model (VSM) and utilisation-focussed evaluation and, falls within the tradition of facilitated modelling approaches to operational research. We argue that this approach worked well in engaging primary evaluation users in a process of collaborative action research to improving an educational development initiative and that the approach helped generate information relevant to answering its primary users’ questions, to inform their specific decisions and actions relevant to their quality enhancement responsibilities. Through a case study, concerning the evaluation of an educational development initiative in a large UK university, we illustrate how the VSM and utilisation-focussed evaluation could be used to: (a) conceptualise the connection between strategies and their components at different levels of organisation; (b) to clarify the role and interests of stakeholders in these strategies; and (c) to scope evaluation to be relevant to informing the decisions and actions of these stakeholders. The paper contributes to illustrate how VSM principles can underpin a theory of change approach to engaging primary stakeholders in planning an intervention and its evaluation in the context of educational development work, in order to improve evaluation to be more relevant to their needs. The paper should be of interest to researchers exploring the use of systems theory in evaluation, in particular in the context of educational development work in higher education