Dynamic merge of discrete goods flow – Impact on throughput and efficiency

Continuous conveyors with a dynamic merge were developed with adaptable control equipment to differentiate these merges from competing Stop-and-Go merges. With a dynamic merge, the partial flows are manipulated by influencing speeds so that transport units need not stop for the merge. This leads to a more uniform flow of materials, which is qualitatively observable and verifiable in long-term measurements. And although this type of merge is visually mesmerizing, does it lead to advantages from the view of material flow technology? Our study with real data indicates that a dynamic merge shows a 24% increase in performance, but only for symmetric or nearly symmetric flows. This performance advantage decreases as the flows become less symmetric, approaching the throughput of traditional Stop-and-Go merges. And with a cost premium for a continuous merge of approximately 10% due to the additional technical components (belt conveyor, adjustable drive engines, software, etc.), this restricts their economical use.

Impact of definitions of loss to follow-up (LTFU) in antiretroviral therapy program evaluation: variation in the definition can have an appreciable impact on estimated proportions of LTFU

OBJECTIVE To examine the impact of different definitions of loss to follow-up (LTFU) on estimates of program outcomes in cohort studies of patients on antiretroviral therapy (ART). STUDY DESIGN AND SETTING We examined the impact of different definitions of LTFU using data from the International Epidemiological Databases to Evaluate AIDS-Southern Africa. The reference approach, Definition A, was compared with five alternative scenarios that differed in eligibility for analysis and the date assigned to the LTFU outcome. Kaplan-Meier estimates of LTFU were calculated up to 2 years after starting ART. RESULTS Estimated cumulative LTFU were 14% and 22% at 12 and 24 months, respectively, using the reference approach. Differences in the proportion LTFU were reported in the alternative scenarios with 12-month estimates of LTFU varying by up to 39% compared with Definition A. Differences were largest when the date assigned to the LTFU outcome was 6 months after the date of last contact and when the site-specific definition of LTFU was used. CONCLUSION Variation in the definitions of LTFU within cohort analyses can have an appreciable impact on estimated proportions of LTFU over 2 years of follow-up. Use of a standardized definition of LTFU is needed to accurately measure program effectiveness and comparability between programs.

Quantifying entrepreneurship and its impact on local economic performance: A spatial assessment in rural Switzerland

Regional and rural development policies in Europe increasingly emphasize entrepreneurship to mobilize the endogenous economic potential of rural territories. This study develops a concept to quantify entrepreneurship as place-dependent local potential to examine its impact on the local economic performance of rural territories in Switzerland. The short-to-medium-term impact of entrepreneurship on the economic performance of 1706 rural municipalities in Switzerland is assessed by applying three spatial random effects models. Results suggest a generally positive relationship between entrepreneurship and local development: rural municipalities with higher entrepreneurial potential generally show higher business tax revenues per capita and a lower share of social welfare cases among the population, although the impact on local employment is less clear. The explanatory power of entrepreneurship in all three models, however, was only moderate. This finding suggests that political expectations of fostering entrepreneurship to boost endogenous rural development in the short-to-medium term should be damped.

Emotional contagion in team sports and its impact on individual performance – an experimental study

In sport psychology research about emotional contagion in sport teams has been scarce (Reicherts & Horn, 2008). Emotional contagion is a process leading to a specific emotional state in an individual caused by the perception of another individual’s emotional expression (Hatfield, Cacioppo & Rapson, 1994). Apitzsch (2009) described emotional contagion as one reason for collapsing sport teams. The present study examined the occurrence of emotional contagion in dyads during a basketball task and the impact of a socially induced emotional state on performance. An experiment with between-subjects design was conducted. Participants (N=81, ♀=38, M=21.33 years, SD=1.45) were randomly assigned to one of two experimental conditions, by joining a confederate to compose a same gender, ad hoc team. The team was instructed to perform a basketball task as quickly as possible. The between-factor of the experimental design was the confederate’s emotional expression (positive or negative valence). The within-factor was participants’ emotional state, measured pre- and post-experimentally using PANAS (Krohne, Egloff, Kohlmann & Tausch, 1996). The basketball task was video-taped and the number of frames participants needed to complete the task was used to determine the individual performance. The confederate’s emotional expression was appraised in a significantly different manner across both experimental conditions by participants and video raters (MC). Mixed between-within subjects ANOVAs were conducted to examine the impact of the two conditions on participants’ scores on the PANAS subscales across two time periods (pre- and post-experimental). No significant interaction effects but substantial main effects for time were found on both PANAS subscales. Both groups showed an increase in positive and a reduction in negative PANAS scores across these two time periods. Nevertheless, video raters assessment of the emotional states expressed by participants was significantly different between the positive (M=3.23, SD=0.45) and negative condition (M=2.39, SD=0.53; t=7.64, p<.001, eta squared=.43). An independent-samples t-test indicated no difference in performance between conditions. Furthermore, no significant correlation between the extent of positive or negative emotional contagion and the number of frames was observed. The basketball task lead to an improvement of the emotional state of participants, independently of the condition. Even though participants PANAS scores indicated a tendency to emotional contagion, it was not statistically significant. This could be explained by the low task duration of approximately three minutes. Moreover, the performance of participants was unaffected by the experimental condition or the extent of positive or negative emotional contagion. Apitzsch, E. (2009). A case study of a collapsing handball team. In S. Jern & J. Näslund (Eds.), Dynamics within and outside the lab. Proceedings from The 6th Nordic Conference on Group and Social Psychology, May 2008, Lund, pp. 35-52. Hatfield, E., Cacioppo, J. T. & Rapson, R. L. (1994). Emotional contagion. Cambridge: University Press. Krohne, H. W., Egloff, B., Kohlmann, C.-W. & Tausch, A. (1996). Untersuchungen mit einer deutschen Version der „Positive und Negative Affect Schedule“ (PANAS). Diagnostica, 42 (2), 139-156. Reicherts, M. & Horn, A. B. (2008). Emotionen im Sport. In W. Schlicht & B. Strauss (Eds.), Enzyklopädie der Psychologie. Grundlagen der Sportpsychologie (Bd. 1) (S. 563-633). Göttingen: Hogrefe.

Floods of the Upper Danube River and Its Tributaries and Their Impact on Urban Economies (c. 1350–1600): The Examples of the Towns of Krems/Stein and Wels (Austria)

This paper examines the impact of disastrous and ‘ordinary’ floods on human societies in what is now Austria. The focus is on urban areas and their neighbourhoods. Examining institutional sources such as accounts of the bridge masters, charters, statutes and official petitions, it can be shown that city communities were well acquainted with this permanent risk: in fact, an office was established for the restoration of bridges and the maintenance of water defences and large depots for timber and water pipes ensured that the reconstruction of bridges and the system of water supply could start immediately after the floods had subsided. Carpenters and similar groups gained 10 to 20 per cent of their income from the repair of bridges and other flood damage. The construction of houses in endangered zones was adapted in order to survive the worst case experiences. Thus, we may describe those communities living along the central European rivers as ‘cultures of flood management’. This special knowledge vanished, however, from the mid-nineteenth century onwards, when river regulations gave the people a false feeling of security.

Pathogenesis of AF: impact on intracardiac signals

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and is responsible for the highest number of rhythm-related disorders and cardioembolic strokes worldwide. Intracardiac signal analysis during the onset of paroxysmal AF led to the discovery of pulmonary vein as a triggering source of AF, which has led to the development of pulmonary vein ablation--an established curative therapy for drug-resistant AF. Complex, multicomponent and rapid electrical activity widely involving the atrial substrate characterizes persistent/permanent AF. Widespread nature of the problem and complexity of signals in persistent AF reduce the success rate of ablation therapy. Although signal processing applied to extraction of relevant features from these complex electrograms has helped to improve the efficacy of ablation therapy in persistent/permanent AF, improved understanding of complex signals should help to identify sources of AF and further increase the success rate of ablation therapy.