Reconstruction of occluded pelvis markers during marker-based motion capture with industrial exoskeletons

Industrial back support exoskeletons are a promising solution to alleviate lumbar musculoskeletal strain. Due to the complexity of spinal loading, evaluation of EMG data alone has been considered insufficient to assess their support effects, and complementary kinematic and dynamic data are required. However, the acquisition of marker-based kinematics is challenging with exoskeletons, as anatomical reference points, particularly on the pelvis, are occluded by exoskeleton structures. The aim of this study was therefore to develop and validate a method to reliably reconstruct the occluded pelvic markers. The movement data of six subjects, for whom pelvic markers could be placed while wearing an exoskeleton, were used to test the reconstructions and compare them to anatomical landmarks during lifting, holding and walking. Two separate approaches were used for the reconstruction. One used a reference coordinate system based on only exoskeleton markers (EXO), as has been suggested in the literature, while our proposed method adds a technical marker in the lumbar region (LUMB) to compensate for any shifting between exoskeleton and pelvis. Reconstruction with EXO yielded on average an absolute linear deviation of 54 mm ± 16 mm (mean ± 1SD) compared to anatomical markers. The additional marker in LUMB reduced mean deviations to 14 mm ± 7 mm (mean ± 1SD). Both methods were compared to reference values from the literature for expected variances due to marker placement and soft tissue artifacts. For LUMB 99% of reconstructions were within the defined threshold of 24 mm ±9 mm while for EXO 91% were outside.

Comparison of two pupillometric measures as indicators of cognitive strain and under the influence of screen luminance

The pupil diameter has been shown to provide insight to a person's experienced cognitive strain. Pupillary light responses, however, make this measure unreliable in uncontrolled settings. Two derived indicators-Index of Cognitive Activity (ICA) and Index of Pupillary Activity (IPA)-aim to 'eliminate' lighting influences, changing based only on the perceived cognitive strain. The IPA potentially offers a valuable alternative to the ICA through its fully transparent calculation, which lifts the restrictions to proprietary software and supported eye trackers. The measures are examined and compared based on two experimental studies; (i) as indicators of cognitive strain during mental arithmetic tasks and (ii) under different conditions of computer screen luminance. Results indicate that neither indicator differentiates between the increasing levels of cognitive strain. Differences in screen luminance are reflected in both indicators, although differently between the conditions. Both results contradict the claims of the indicators and further investigations are thus required.

Comparing risk assessment methods for work-related musculoskeletal disorders with in vivo joint loads during manual materials handling

The validity of observational methods in ergonomics is still challenging research. Criterion validity in terms of concurrent validity is the most commonly studied. However, studies comparing observational methods with biomechanical values are rare. Thus, the aim of this study is to compare the Ovako Working Posture Analysing System (OWAS) and the Rapid Entire Body Assessment (REBA) with in vivo load measurements at hip, spine, and knee during stoop and squat lifting of 14 participants. The results reveal that OWAS and REBA action levels (AL) can distinguish between different in vivo load measurements during manual lifting. However, the results also reveal that the same OWAS- and REBA-AL do not necessarily provide equal mean values of in vivo load measurements. For example, resultant contact force in the vertebral body replacement for squat lifting ranged from 57% body weight (%BW) in OWAS-AL1 to 138%BW in OWAS-AL3 compared to 46%BW in REBA-AL0 and 173%BW in REBA-AL3. Furthermore, the results suggest that the performed squat lifting techniques had a higher risk for work-related musculoskeletal disorders than the performed stoop lifting techniques.

In vivo load on knee, hip and spine during manual materials handling with two lifting techniques

It is generally accepted that the lifting technique strongly influences physical loads within the human body and, thus, the risk of musculoskeletal disorders. However, there is a lack of knowledge regarding whether particular lifting techniques are effective in reducing loads. Hence, this retrospective study quantified (partly published) in vivo loads at joints within the human body during two typical lifting techniques, stoop lifting and squat lifting. Patients who had received instrumented implants underwent in vivo load measurements at either the knee (two patients), the hip (eight patients), or the upper lumbar spine (four patients) while lifting a 10 kg weight frontally with either straight (stoop) or bent (squat) knees. Contact forces and moments and the orientation of the contact force vector were determined and examined using the paired t test of Statistical Parametric Mapping. The two lifting techniques did not differ in terms of load magnitudes but did differ in terms of directions: (i) at the hip joint, the load vector varied significantly (p < 0.05) in the frontal and sagittal planes, (ii) at the knee joint, the load vector differed significantly (p < 0.05) in the sagittal plane (iii) while the load vector and magnitude did not differ at the upper lumbar spine (p > 0.05). Our findings indicate that the lifting technique causes changes in the orientation rather than the magnitude of lower extremity joint contact loads. Even though this quantification could only be performed in a small group of patients, the quantification of the relevance of such lifting technique recommendations will hopefully guide future recommendations towards a more scientific interpretation.

Work interruptions of office workers: The influence of the complexity of primary work tasks on the perception of interruptions

BACKGROUND

Research demonstrates that work interruptions are considered one of the most common work stressors. Understanding the mechanisms of work interruptions is therefore vital to reducing worker stress and maintaining performance.

OBJECTIVE

The aim of this research is to investigate the influence of the frequency of work interruptions on subjective workload in the context of office work. Specifically, the mediating influence of interruption perception as well as the moderating influence of the complexity of the primary task are examined.

METHOD

The work interruptions of 492 office workers in Germany were collected by means of a one-day diary study. A mediation model and a conditional indirect effect model were calculated to examine the influence of interruption frequency on subjective workload, mediated by the individual perception of these interruptions as well as moderated by the complexity of the primary work tasks.

RESULTS

The analyses indicated a significant mediation and moderation. This implies that, on the one hand, the perception of work interruptions significantly mediates the relationship between the frequency of work interruptions and subjective workload. On the other hand, more complex primary work tasks seem to strengthen the positive relationship between interruption frequency and perceived interruption overload.

CONCLUSION

The study underlines that work interruptions need to be considered in a much more differentiated way than is currently the case. Both in research and in terms of intervention measures in the work context, the various influencing factors need to be identified for an assessment of the effects on the working person to be possible.

Do multimodal search cues help or hinder teleoperated search and rescue missions?

In search and rescue missions, teleoperated rovers equipped with sensor technology are deployed into harsh environments to search for targets. To support the search task, unimodal/multimodal cues can be presented via visual, acoustic and/or haptic channels. However, human operators often perform the search task in parallel with the driving task, which can cause interference of attentional resources based on multiple resource theory. Navigating corners can be a particularly challenging aspect of remote driving, as described with the Cornering Law. Therefore, search cues should not interfere with cornering. The present research explores how unimodal/multimodal search cues affect cornering performance, with typical communication delays of 50 ms and 500 ms. One-hundred thirty-one participants, distributed into two delay groups, performed a target search task with unimodal/multimodal search cues. Search cues did not interfere with cornering performance with 50 ms delays. For 500 ms delays, search cues presented via the haptic channel significantly interfered with the driving task. Practitioner summary: Teleoperated rovers can support search and rescue missions. Search cues may assist the human operator, but they may also interfere with the task of driving. The study examined interference of unimodal and multimodal search cues. Haptic cues should not be implemented for systems with a delay of 500 ms or more.

Digital platforms: Perceived criteria of success, importance of work design, occupational safety and health for present and prospective digital platforms

BACKGROUND:

Digital platforms have found their way into all our lives: they are discussed in political, economic, scientific and public fields worldwide. Platform-based work is also on the rise in the German labour market, not only in institutionalised work, but also in start-ups and spin-offs.

OBJECTIVES:

The article describes the results of an analysis aimed at identifying perceptions of new and already known major success factors on market entry and market penetration regarding occupational safety and health (OSH) and work design.

METHODS:

A total of 31 semi-standardised interviews were conducted with 39 people. First, perceived success factors in general were examined with the comparative analysis. Surprisingly, OSH/work design factors did not emerge as perceived success factors. For this reason, a in-depth analysis was performed in a secondary analysis with the structured content analysis.

RESULTS:

Identified perceived success factors were user orientation, scalability, network effects, niche occupation. The in-depth secondary analysis with focus on OSH/work design showed that the interviewees are aware of the topic of OSH/work design, but did not consider it to be important to economic success.

CONCLUSIONS:

The identified success factors may not seem surprising. What is surprising, however, is the role played by OSH/work design. Solutions must be developed that sensitize working persons in the platform sector to the topic of OSH/work design. A two-step process may be useful: First, uniform regulations and laws must be anchored in the platform architecture. Second, various measures and training courses can be designed to inform and raise awareness.

Why cumulative loading calculated using non-weighted integration may not be suitable for assessing physical stress of the lower back: an empirical investigation of strain during lifting and lowering tasks

When work-related physical stress is assessed using non-weighted integration, it is assumed that different loading conditions have a sufficiently comparable effect on the human body as long as the area under the loading curve is the same. Growing evidence cast doubt on whether this simple calculation can adequately estimate physical work-related strain. This study investigates in vivo, focussing on the lower back, whether the non-weighted method adequately reflects work-related physical strain of the lower back. Strain data resulting from lifting/lowering tasks performed in a laboratory study with an identical area under the loading curve but different load intensities were compared. Results showed that the non-weighted method does not sufficiently reflect the resulting muscular, cardiovascular and perceived strain but underestimates the influence of higher load intensity even in the range of medium physical exposure. Further research is needed regarding the determination of weighting factors and limit values. Practitioner Summary Given the dynamic nature of most physical work activities, the assessment of time-varying loading of the lower back is of particular interest in practice. Results show that the widely used non-weighted calculation method does not accurately reflect the resulting physical strain but underestimates the influence of higher load intensity.Abbreviations: MSD: musculoskeletal disorders; WMSD: work-related musculoskeletal disorders; KIM-LHC: Key Indicator Method Lifting, Holding, Carrying; RES: right erector spinae longissimus; LES: left erector spinae longissimus; HR: heart rate; RPE: rating of perceived exertion; EMG: surface electromyography; ECG: electrocardiography; SENIAM: Surface ElectroMyoGraphy for the Non-Invasive Assessment of Muscles; MVC: maximum voluntary contraction; ANOVA: analysis of variance; Std. error: standard error HIGHLIGHTSResults of this empirical investigation suggest that the widely used non-weighted calculation method is not fully suitable for calculating cumulative loading of the lower back.Even in the range of medium physical exposure the non-weighted calculation method does not accurately reflect the resulting strain on the human body but tends to underestimate the influence of higher load intensity due to higher external weight.Despite the same cumulative loading value obtained when using the non-weighted method, the resulting physical strain values are generally about 20-25% higher.The results may be used to further develop ergonomic assessment methods in order to avoid a misclassification of loading conditions and to prevent the risk of overexertion.

[Work design measures and solutions for dealing with the COVID-19 pandemic: A systematic analysis of work in the primary, secondary, and tertiary sectors in Germany]

Die mit der Ausbreitung der COVID-19 Pandemie in Deutschland einhergehende Anforderung betriebliche Arbeitsabläufe an die gesetzlichen Hygiene- und Kontaktreduktionsvorgaben anzupassen, hat zu kurzfristigen und teilweise radikalen Veränderungen in der Arbeitswelt geführt. Im Rahmen des Forschungsvorhabens COVID19LL wurde basierend auf 52 Interviews mit Unternehmens- und Organisationsvertretungen analysiert, welche pandemiebedingten Veränderungen im Kontext der Arbeit überregional und sektorenübergreifend auftreten, wie diese zu bewerten sind und welche neuen Arbeitsweisen sich auch in einer postpandemischen Zeit bewähren könnten. Im Einklang mit anderen Untersuchungen konnten eine steigende Flexibilisierung von Arbeitsort und Arbeitszeit, eine Beschleunigung der Digitalisierung von Arbeitsprozessen sowie Auswirkungen auf die Führungskultur festgestellt werden. Weitere zentrale Erfahrungen beziehen sich auf die Anpassung interner und externer Kommunikationsprozesse sowie den operativen Umgang mit krisenbedingten Herausforderungen. Anhand der gesammelten Daten wurden Handlungsempfehlungen für Unternehmen in Form von normativ-narrativen Szenarien abgeleitet.

Praktische Relevanz: Die vorgestellten Ergebnisse zeigen in der Praxis erfolgreich umgesetzte Maßnahmen zur Bewältigung der krisenbedingten Herausforderungen sowie Ansätze für die künftige Weiterentwicklung von Arbeitsformen. Die Maßnahmen werden durch die Darlegung erforderlicher Rahmenbedingungen und Erfolgsfaktoren kontextualisiert, wodurch der Transfer in andere Unternehmen und Wirtschaftszweige gefördert wird.

A meta-analytic review of the reliability of the Index of Cognitive Activity concerning task-evoked cognitive workload and light influences

The Index of Cognitive Activity (ICA) was introduced as a promising pupillary workload measure for field investigations since, unlike pupil dilation, it is not affected by illumination. Recent studies have investigated the ICA for task-evoked cognitive workload with contradictory findings. However, few studies investigated the influence of illumination on the ICA. Therefore, to examine inconsistencies regarding the reliability for workload measurement and the effects of light, a meta-analysis was conducted based on a structured literature review. The meta-analysis considered k = 14 studies with a total sample size of N = 751 participants. Results showed significant effects for workload (r = 0.61) and light (r = 0.45) on the ICA. Since moderating effects were found for several between-study differences, it seems likely that different cognitive processes and settings affect the indicator and should be considered in empirical investigations. According to the findings, the ICA is a reliable indicator for task-evoked workload. However, light influences were found which indicates that evidence-based conclusions regarding the ICA's practical applicability require further research.

Accuracy of a markerless motion capture system for postural ergonomic risk assessment in occupational practice

Established methods for postural ergonomic risk assessment in occupational practice are mostly time-consuming and need to be conducted by experts. Use of technology could improve postural ergonomic risk assessments with regard to time efficiency and accuracy. A study was conducted to assess the accuracy of a markerless motion capture system (Microsoft Kinect V2) compared to a marker-based motion capture system (Vicon Bonita). Angles of different body segments were analysed. The results show major inaccuracies of the markerless motion capture system for capturing axial trunk rotation (mean angular deviation of 14.04°) indicating that potential health risks could be underestimated. Combined working postures of axial trunk rotation and arm anteversion show issues with self-occlusion. Based on the findings, it is discussed whether the detected inaccuracies for axial trunk rotation are likely to lead to overestimation or underestimation of potential health risks when conducting an ergonomic risk assessment.

The Index of Cognitive Activity - Eligibility for task-evoked informational strain and robustness towards visual influences

Various researchers have proposed pupillometric indicators to assess a person's cognitive strain. However, to distinguish the variation of pupil light response from psychosensory pupil response in experimental field conditions is a challenge. The Index of Cognitive Activity (ICA) addresses this problem by wavelet separation. This research investigates the ICA's sensitivity for multiple level task-evoked cognitive activity and visual influences concerning informational work tasks. Objective and subjective measures assessed cognitive strain of participants (N = 22) during various tasks. In a first experiment, mental arithmetic tasks were used to induce different levels of cognitive activity. In a second experiment, influences of screen polarity and presentation of information were investigated (N = 18). The results indicate that eye metrics are rarely sensitive to slight variations in task difficulty. Moreover, the ICA is likely to be sensitive towards constant screen illumination and shows tendencies regarding changes in displayed information. Possible ramifications for the objective assessment of cognitive strain are discussed.

Prediction model of the effect of postural interactions on muscular activity and perceived exertion

Musculoskeletal disorders are a prevalent disease in many Western countries. While a large number of ergonomic analyses and assessment methods are nowadays available, most current methods that assess exposure calculate overall risk scores of individual body segments without considering interaction effects of exposure variables. Therefore, a study was conducted that aimed at investigating and quantifying interaction effects of trunk inclination and arm lifting on ratings of perceived exertion (RPE) and muscle activity. A multiple regression model to predict musculoskeletal load under consideration of interaction effects was derived. The study revealed that there is a significant interaction effect of trunk inclination and arm lifting. Furthermore, final regression models explained variance in exposure variables in a range of R² = 0.68 to R² = 0.147 with a subset of two to three inputs. The predicative equations support the computer-based post-processing of sensor data. Practitioner summary: This article elaborates on the importance of interaction effects of working postures on assessment results of load. In practise, easy to-use-methods for an assessment of working postures are needed. Therefore, a regression model is derived, which facilitates the quantification of work load under consideration of interaction effects. The use of this regression model for the assessment of posture data gathered by range sensors is recommended. Abbreviations: RPE: rating of perceived exertion; MSD: musculoskeletal disorder; OWAS: ovako working posture analysing system; RULA: rapid upper limb assessment; LUBA: postural loading on the upper body assessment; REBA: rapid entire body assessment; OCRA: occupational repetitive action;S D: standard deviation; EMG: surface electromyography; LUT: left upper trapezius pars descendens; RUT: right upper trapezius pars descendens; LLT: left trapezius pars ascendens; RLT: right trapezius pars ascendens; LAD: left anterior deltoideus; RAD: right anterior deltoideus; LES: left erector spinae longissimus; RES: right erector spinae longissimus; SENIAM: surface electroMyoGraphy for the non-invasive assessment of muscles; MVC: maximum voluntary contraction; MANOVA: multivariate analysis of variance; ANOVA: analysis of variance; OLS: ordinary least squares; MANCOVA: multivariate analysis of covariance.

AMICAI: A Method Based on Risk Analysis to Integrate Responsible Research and Innovation into the Work of Research and Innovation Practitioners

The integration of ethics into the day-to-day work of research and innovation (R&I) is an important but difficult challenge. However, with the Aachen method for identification, classification and risk analysis of innovation-based problems (AMICAI) an approach from an engineering perspective is presented that enables the integration of ethical, legal and social implications into the day-to-day work of R&I practitioners. AMICAI appears in particular capable of providing a procedural guidance for R&I practitioners based on a method established in engineering science, breaking down the object of consideration into partial aspects and prioritizing the innovation-based problems in dependence of potential risk. This enables the user to apply AMICAI continuously during all stages of the research and development (R&D) process and to analyze and choose between certain sociotechnical alternatives. In this way, problems that affect ethical, legal, and social aspects can be understood, reflected and considered in the mostly technically focused R&D process. The paper gives a general guidance about AMICAI by describing principles and assumptions, providing the steps of analysis and application aids, giving an example application, explaining the necessary adjustments of AMICAI compared to the methodical basis of failure mode, effects, and criticality analysis and discussing the advantages and limits. AMICAI's simple applications can stimulate interdisciplinary cooperation in the R&D process and be a starting point for the development of an "open RRI risk analysis platform" allowing society to evaluate innovation-based problems.

Human–Robot Collaboration Acceptance Model: Development and Comparison for Germany, Japan, China and the USA

The use of robots in the national economy—especially in industrialized countries—is growing. At the same time, the interdependency between humans and robots is getting increasingly closer: they are engaging in direct contact with each other as more and more organizations let robots and humans work hand-in-hand. One factor that predicts successful human–robot interdependency is the acceptance of the robot by the human. Generally, only when an innovative assistive working system covers human needs and expectations, it is perceived to be useful and hence accepted. Furthermore, it has been found that cultural context has an impact on human–robot interaction, as people feel more comfortable interacting with a robot in a culturally normative way. Therefore this paper aims at presenting a human–robot collaboration acceptance model (HRCAM) with regard to the collaboration between humans and robots that is based on prior acceptance models, while also considering technology affinity and ethical, legal and social implications. Additionally, similarities and differences in robot acceptance are shown for four selected countries—both in comparison to the overall human–robot collaboration acceptance model and between the countries. The HRCAM additionally shows which variables influence perceived usefulness and perceived ease of use, and thus behavioral intention to use and use behavior. A further distinction is made between anchor variables, which can be influenced in the long term, and adjustment variables, which can be influenced in the short to medium term. The model therefore offers practitioners in the field of human–robot collaboration recommendations to increase the acceptance of robots.

Predicting technology usage by health information need of older adults: Implications for eHealth technology

BACKGROUND

Information and communication technology increasingly addresses the information needs patients have regarding their personal health. While an understanding of older adults' needs is crucial for developing successful eHealth technology, user research results hardly apply to different systems.

OBJECTIVE

The present study aims at: (1) describing and analysing the context of digital health systems in a general manner, (2) investigating if information need of older adults influences their technology usage to show the relevance of the concept for a general context analysis and (3) testing which demographic variables intervene with their health information need.

METHODS

Survey data from a longitudinal study with older adults (N = 551) were reported descriptively. After showing a significant relationship during chi-square tests, we quantified the ones between general health information need and technology usage, as well as between general health information need and the demographic variables age, education, chronic diseases and gender by means of (multiple) linear regression models.

RESULTS

We predicted older adults' technology usage based on their health information need. The results confirmed this relationship. Higher information need led to a more frequent usage of apps installed on the tablet personal computer (PC), to a frequent use of smartwatches and to the possession of a computer or laptop. Users' education has a higher impact on health information need than amount of chronic diseases, gender and age.

CONCLUSIONS

Information need emerged as a useful object for investigation of context and user requirement analysis across different systems: it predicted technology usage so that design recommendations derived from the descriptive gained in importance.

Investigation of observational methods assessing workload of static working postures based on surface electromyography

BACKGROUND:

A large number of different methods are available to identify and assess working postures. Although observation-based methods are most commonly used in practise, investigations showed different results regarding validity of such methods.

OBJECTIVE:

To investigate validity of one of the most commonly used observation-based assessment method in ergonomics, the Ovako Working Posture Analysing System (OWAS) and the European standard EN 1005-4 for evaluation of working postures, an experimental laboratory study was conducted.

METHODS:

Muscle activity was measured under combinations of static working postures of trunk inclination and shoulder flexion to compare these measurements and observation-based assessments according to OWAS and EN 1005-4. In order to investigate the magnitude of correspondence between muscle activity and observation-based assessments, Spearman rank correlation coefficients (r_s) were calculated.

RESULTS:

Significant correlations were found between OWAS and muscle activity (range from r_s² = 0.17 r_s² = 0.55). Significant correlations were found between EN 1005-4 and muscle activity (range from r_s² = 0.34 to r_s² = 0.74).

CONCLUSIONS:

Results emphasise a need for further developments of observation-based methods, since the two investigated methods showed a variance of validity ranging from small to large. Such improvements may also form a better basis for the ergonomic improvement of working conditions in practise, which is highly necessary due to a constantly high prevalence of MSDs in the last decades.

Satisfying Product Features of a Fall Prevention Smartphone App and Potential Users' Willingness to Pay: Web-Based Survey Among Older Adults

Background

Prohibiting falls and fall-related injuries is a major challenge for health care systems worldwide, as a substantial proportion of falls occur in older adults who are previously known to be either frail or at high risk for falls. Hence, preventive measures are needed to educate and minimize the risk for falls rather than just minimize older adults’ fall risk. Health apps have the potential to address this problem, as they enable users to self-assess their individual fall risk.

Objective

The objective of this study was to identify product features of a fall prevention smartphone app, which increase or decrease users’ satisfaction. In addition, willingness to pay (WTP) was assessed to explore how much revenue such an app could generate.

Methods

A total of 96 participants completed an open self-selected Web-based survey. Participants answered various questions regarding health status, subjective and objective fall risk, and technical readiness. Seventeen predefined product features of a fall prevention smartphone app were evaluated twice: first, according to a functional (product feature is implemented in the app), and subsequently by a dysfunctional (product feature is not implemented in the app) question. On the basis of the combination of answers from these 2 questions, the product feature was assigned to a certain category (must-be, attractive, one-dimensional, indifferent, or questionable product feature). This method is widely used in user-oriented product development and captures users’ expectations of a product and how their satisfaction is influenced by the availability of individual product features.

Results

Five product features were identified to increase users’ acceptance, including (1) a checklist of typical tripping hazards, (2) an emergency guideline in case of a fall, (3) description of exercises and integrated workout plans that decrease the risk of falling, (4) inclusion of a continuous workout program, and (5) cost coverage by health insurer. Participants’ WTP was assessed after all 17 product features were rated and revealed a median monthly payment WTP rate of €5.00 (interquartile range 10.00).

Conclusions

The results show various motivating product features that should be incorporated into a fall prevention smartphone app. Results reveal aspects that fall prevention and intervention designers should keep in mind to encourage individuals to start joining their program and facilitate long-term user engagement, resulting in a greater interest in fall risk prevention.

A mobile application improves therapy-adherence rates in elderly patients undergoing rehabilitation: A crossover design study comparing documentation via iPad with paper-based control

Medication adherence is crucial for success in the management of patients with chronic conditions. This study analyzes whether a mobile application on a tablet aimed at supporting drug intake and vital sign parameter documentation affects adherence in elderly patients.Patients with coronary heart disease and no prior knowledge of tablet computers were recruited. They received a personal introduction to the mobile application Medication Plan, installed on an Apple iPad. The study was conducted using a crossover design with 3 sequences: initial phase, interventional phase (28 days of using the app system), and comparative phase (28 days of using a paper diary). Users experienced the interventional and comparative phases alternately.A total of 24 patients (12 males; mean age 73.8 years) were enrolled in the study. The mean for subjectively assessed adherence (A14-scale; 5-point Likert scale, from "never" to "very often" which results in a score from 0 to 56) before the study was 50.0 (SD = 3.44). After both interventions there was a significant increase, which was more pronounced after the interventional phase (54.0; SD = 2.01) than after the comparative phase (52.6; SD = 2.49) (for all pairs after both interventions, P <0.001). Neither medical conditions nor the number of drug intake (amount and frequency of drug taking) per day affected subjective adherence. Logging data showed a significantly stronger adherence for the medication app than the paper system for both blood pressure recordings (P <0.001) and medication intake (P = 0.033). The majority of participants (n = 22) stated that they would like to use the medication app in their daily lives and would not need further assistance with the app.A mobile app for medication adherence increased objectively and subjectively measured adherence in elderly users undergoing rehabilitation. The findings have promising clinical implications: digital tools can assist chronic disease patients achieve adherence to medication and to blood pressure measurement. Although this requires initial offline training, it can reduce complications and clinical overload because of nonadherence.

Demographic and health related data of users of a mobile application to support drug adherence is associated with usage duration and intensity

PURPOSE

A wealth of mobile applications are designed to support users in their drug intake. When developing software for patients, it is important to understand the differences between individuals who have, who will or who might never adopt mobile interventions. This study analyzes demographic and health-related factors associated with real-life "longer usage" and the "usage-intensity per day" of the mobile application "Medication Plan".

METHODS

Between 2010-2012, the mobile application "Medication Plan" could be downloaded free of charge from the Apple-App-Store. It was aimed at supporting the regular and correct intake of medication. Demographic and health-related data were collected via an online questionnaire. This study analyzed captured data.

RESULTS

App-related activities of 1799 users (1708 complete data sets) were recorded. 69% (1183/1708) applied "Medication Plan" for more than a day. 74% were male (872/1183), the median age 45 years. Variance analysis showed a significant effect of the users' age with respect to duration of usage (p = 0.025). While the mean duration of use was only 23.3 days for users younger than 21 years, for older users, there was a substantial increase over all age cohorts up to users of 60 years and above (103.9 days). Sex and educational status had no effect. "Daily usage intensity" was directly associated with an increasing number of prescribed medications and increased from an average of 1.87 uses per day and 1 drug per day to on average 3.71 uses per day for users stating to be taking more than 7 different drugs a day (p<0.001). Demographic predictors (sex, age and educational attainment) did not affect usage intensity.

CONCLUSION

Users aged 60+ as well as those with complicated therapeutic drug regimens relied on the service we provided for more than three months on average. Mobile applications may be a promising approach to support the treatment of patients with chronic conditions.

Design recommendations for the creation of icons for the elderly

During employment of icons in order to represent system functions, specific user requirements from elderly people have not been scientifically gathered and thus will merely be considered during the process of system design. The survey, with explicit consideration of technology acceptance and experience of 120 elderly probands, looked into the comprehension of four different classes of non-animated graphical representations. It was shown that among elderly, the use of photos compared to pictograms or clip art leads to a significantly higher recognition rate. The mapping of actions rather than objects leads to a further reduction of the error probability and is thus, especially in the context of telemedicine, preferable for the target group.

Spontaneous immortalization of neural crest-derived corneal progenitor cells after chromosomal aberration

OBJECTIVES

In a previous study, we have reported the existence of neural crest-derived stem cell-like cells originating from the corneal limbus of juvenile mice (termed murine corneal cells, MCCs). To yield a sufficient number of MCCs, for example, for cell-therapy approaches, here we have investigated MCCs' ability for extensive proliferation, and we have evaluated their stem cell qualities and genetic stability after large-scale culture.

MATERIALS AND METHODS

MCCs were established from corneal limbal tissue of juvenile mice. To determine their cell proliferation and self-renewing potential, MTT tests and an estimation of colony forming unit efficiency were carried out. Multipotency of cell differentiation was examined by applying adipogenic and osteogenic differentiation protocols. Moreover, karyotyping was performed and expression of stem cell markers and cell cycle-associated genes was analysed.

RESULTS

MCCs, as primary cells, could be cultured for more than 60 passages. We observed increased cell proliferation and high number of colony forming units (CFUs) after extensive culture. Interestingly, there were no changes in expression of MCC markers. Furthermore, cell differentiation potentials remained comparable with MCCs at early passages. However, karyotyping revealed numeric chromosomal aberrations at higher passages. Moreover, tumour suppressor genes such as p16 and p21 were found to be down-regulated after large-scale cell culture.

CONCLUSIONS

MCCs immortalize spontaneously after extensive cell culture, but still demonstrate stem cell-like qualities.

Dislocation cross-slip in nanocrystalline fcc metals

Constant strain rate molecular dynamics simulations of nanocrystalline Al demonstrate that a significant amount of dislocations that have nucleated at the grain boundaries, exhibit cross-slip via the Fleischer mechanism as they propagate through the grain. The grain boundary structure is found to strongly influence when and where cross-slip occurs, allowing the dislocation to avoid local stress concentrations that otherwise can act as strong pinning sites for dislocation propagation.

Structural and mechanistic implications of the amino acid sequence of calcium-transporting ATPases

Work is reviewed in which the amino acid sequences of two Ca2+-transporting ATPases of sarcoplasmic reticulum (SR) from slow (or cardiac) and fast skeletal muscle were determined from the nucleotide sequences of cloned cDNAs. Analysis of hydrophobicity and secondary structure, combined with the known shape derived from electron micrographs, leads to a model of five domains with functional implications. The major globular part of the molecule is in the cytoplasm and consists of one antiparallel and two parallel beta-sheet domains. One of the latter binds ATP, which, in the presence of Ca2+, phosphorylates an aspartic acid on the other domain. It is proposed that subsequent kinase-like movements are transmitted to the SR membrane via a penta-helical, calcium-binding stalk. The Ca2+ is first trapped and then translocated via the ten helices which constitute the transmembrane (channel) region. The difference in requirements for counter ions between the Ca2+- and Na+/K+-ATPases can be explained in terms of differing charge distributions in this channel.

Expressed emotion, family environment, and parental bonding in bulimia nervosa: a 6-year investigation

As part of a prospective, long-term treatment study, 30 in-patients with bulimia nervosa (BN) were divided into groups with high and low expressed emotion (EE) family backgrounds according to the Camberwell Family Interview, and followed for a period of six years. The high EE group initially showed significantly more psychopathology than the low EE group. No group x time interactions were found, but the high EE group showed a worse outcome on the "conflict" and "organisation" subscales of the Family Environment Scale. They also showed significantly more eating disorder pathology according to the Eating Disorder Inventory (EDI) and the Structured Interview for anorexia nervosa (AN) and BN before treatment at discharge, after two years and, to some degree, even after six years. Depth of depression (Beck Depression Inventory) was significantly higher in the high EE group at admission (moderate depression), discharge and after the 6-year follow-up (still slight depression). The Parental Bonding Instrument (PBI) showed no differences between the high EE and low EE groups, but the individuals with "affectionless control" according to the PBI had more negative scores on three of the subscales of the Family Environment Scale (FES). In brief, the high EE individuals with BN were initially sicker and did not fully catch up over time in comparison with the symptomatic recovery of the low EE individuals. These data suggest that EE status upon admission to in-patient treatment is a relevant predictor of the severity and course of BN and depressive symptoms.