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Evolution of stock market efficiency in Europe: Evidence from measuring periods of inefficiency
(2024)
This study introduces novel measures to quantify periods of market inefficiency, enabling precise analysis of their evolution over time and effective comparisons across markets or groups of markets. These measures are applied to an extensive dataset comprising stock indices from 25 European countries from 2007 to 2022. The empirical findings reveal a 20% increase in market inefficiency across Europe, primarily driven by heightened average inefficiencies in the stock markets of the group of developed European countries such as Germany and the Scandinavian countries.
Reliability of a clinical sensory test battery in patients with spine-related leg and arm pain
(2024)
Background: The current standard to evaluate the presence of somatosensory dysfunctions is quantitative sensory testing, but its clinical utility remains limited. Low-cost and time-efficient clinical sensory testing (CST) batteries have thus been developed. Recent studies show moderate to substantial reliability in populations with neuropathic pain. This study evaluates the inter- and intra-tester reliability of people with spine-related leg and arm pain, representing mixed pain mechanisms.
Methods: Fifty-three patients with spine-related leg (n = 41) and arm pain (n = 12) attended three CST sessions. The CST battery consisted of eleven tests, determining loss and gain of sensory nerve function. CST was performed by the same investigator twice and by an additional investigator to determine inter- and intra-tester reliability. Fleiss' (inter-tester) and Cohen's (intra-tester) kappa were calculated for dichotomized and intraclass correlation coefficients (ICC) for continuous outcomes.
Results: Fleiss' kappa varied among modalities from fair to substantial (κ = 0.23–0.66). Cold, warm, and vibration detection thresholds and cold and pressure pain thresholds reached kappa >0.4 (moderate to substantial reliability). Cohen's kappa ranged from moderate to substantial (κ = 0.45–0.66). The reliability of the windup ratio was poor (ICC <0.18).
Conclusion: CST modalities with moderate to substantial inter-tester reliability could be of benefit as a screening tool. The moderate to substantial intra-tester reliability for all sensory modalities (except windup ratio) supports their potential use in clinical practice and research to monitor somatosensory changes over time in patients with spine-related limb pain of mixed pain mechanisms.
Significance: We already know that most modalities of clinical sensory test (CST) batteries achieve moderate to substantial inter- and intra-tester reliability in populations with neuropathic pain.
This study evaluates the reliability of a CST battery in populations with mixed pain mechanisms. We found inter-tester reliability varied from poor to substantial for sensory modalities, questioning the value of some CST modalities. The CST battery showed moderate to substantial intra-tester reliability, suggesting its usefulness to monitor sensory changes over time in this cohort.
Background: The environmental impact of electric scooters has been the subject of critical debate in the scientific community for the past 5 years. The data published so far are very inhomogeneous and partly methodologically incomplete. Most of the data available in the literature suffer from an average bias of 34%, because end-of-life (EOL) impacts have not been modelled, reported or specified. In addition, the average lifetime mileage of shared fleets of e-scooters, as they are operated in cities around the world, has recently turned out to be much lower than expected. This casts the scooters in an unfavourable light for the necessary mobility transition. Data on impact categories other than the global warming potential (GWP) are scarce. This paper aims to quantify the strengths and weaknesses of e-scooters in terms of their contribution to sustainable transport by more specifically defining and extending the life cycle assessment (LCA) modelling conditions: the modelling is based on two genuine material inventories obtained by dismantling two different e-scooters, one based on a traditional aluminium frame and another, for the first time, based on plastic material.
Results: This study provides complete inventory data to facilitate further LCA modelling of electric kick scooters. The plastic scooter had a 26% lower lifetime GWP than the aluminium vehicle. A favourable choice of electric motor promises a further reduction in GWP. In addition to GWP, the scooter's life cycles were assessed across seven other impact categories and showed no critical environmental or health impacts compared to a passenger car. On the other hand, only the resource extraction impact revealed clear advantages for electric scooters compared to passenger cars.
Conclusions: Under certain conditions, scooters can still be an important element of the desired mobility transition. To assure a lifetime long enough is the crucial factor to make the electric scooter a favourable or even competitive vehicle in a future sustainable mobility system. A scooter mileage of more than 5400 km is required to achieve lower CO2eq/pkm emissions compared to passenger cars, which seems unlikely in today's standard use case of shared scooter fleets. In contrast, a widespread use of e-scooters as a commuting tool is modelled to be able to save 4% of greenhouse gas (GHG) emissions across the German mobility sector.
Dielectric properties of unidirectional and biaxial flax/epoxy composites at frequencies up to 1 GHz
(2023)
The relative permittivity of flax/epoxy composites in unidirectional and biaxial orientations was mapped in the frequency range of 1 kHz to 200 kHz, and for the first time in the range of 1 MHz to 1 GHz. In addition, permittivity was investigated for the first time in the temperature range between − 20 °C and 50 °C. These composites, produced using the vacuum infusion process, are increasingly used for sustainable and lightweight structural components in the automotive industry. The relative permittivity was determined using a self-developed plate capacitor with an LCR bridge and an impedance analyzer. An examination of the microstructure of the flax/epoxy composites shows that the fibers are disordered in the composite, resulting in local variations in fiber volume fraction. Furthermore, it was shown that the matrix also infiltrates into the fiber itself, resulting in an increase of the matrix fraction. It was found that unidirectional fabrics had a higher relative permittivity than biaxial fabrics, due to a higher fiber volume fraction and lower proportion of epoxy. The results suggest that it is the fiber volume fraction, rather than the manufacturing process and fiber orientation, that primarily determines the relative permittivity. It was also found that the permittivity continues to decrease below room temperature and thus behaves in a manner typical of the material in this temperature range as well.
Purpose – The COVID-19 pandemic has had a significant impact on the food tourism industry, leading to business closures and a drop in demand. In response to this challenge, virtual food tourism experiences such as VR have emerged as an alternative to traditional in-person experiences. Aim of this paper is to model consumer adoption of virtual food tourism by integrating the Diffusion of Innovation Theory and the Self-determination Theory.
Methodology/Design/Approach – The Diffusion of Innovation Theory explains the process of innovation adoption, while the Self-determination Theory focuses on consumer motivation. This article proposes that intrinsic (autonomy, relatedness, and competence) and extrinsic (relative advantage, complexity, compatibility, trialability, and observability) motivating factors influence virtual food tourism adoption.
Findings – The study suggests that extrinsic motivators can act as mediators between intrinsic motivation and adoption intention. Integrating these two theories provides a comprehensive understanding of the motivations and mechanisms driving virtual food tourism adoption. It also paves the way for the exploration of intrinsic and extrinsic motivations and specific mechanisms underlying adoption behaviours.
Originality of the research – Destinations, businesses, and policy makers can better navigate the changing landscape of food tourism and leverage the potential of virtual food tourism to create engaging, accessible, and culturally enriching experiences.
Ephemeroptera, Plecoptera and Trichoptera are three orders of freshwater macroinvertebrates with a short terrestrial adult life-stage that they use to disperse by flying upstream. This aerial dispersal can be assisted by native riparian forest, but regional variation has not yet been empirically tested. In this study we compared the EPT community of 153 sampling sites located in freshwater streams in four European regions (Central Plains, Central Highlands, Alps, Iberia). In each site, we assessed the EPT community dispersal ability using the Species Flying Propensity index. We also calculated the native deciduous forest cover in the riparian buffer and several environmental stressors such as saprobic pollution or catchment anthropization. Finally, we tested which of these parameters have a significant effect on the EPT community. In the Central Highlands and in Iberia, the share of weak dispersers increased with native deciduous forest cover, indicating a positive effect on dispersal of EPTs. In the Central Plains and the Alps, no such effect was found. We conclude that the effect of native deciduous forest depends on regional landscape characteristics and the regional species pool, but considering the dispersal of the regional EPT communities is needed to create effective river management policies.
Evaluation of a blended learning approach on stratified care for physiotherapy bachelor students
(2023)
Background: Stratified models of care are valuable for addressing psychosocial factors which influence the outcome of patients with musculoskeletal disorders. Introducing such models in undergraduate training has the potential to propagate this knowledge with evidence and foster its implementation. The objective of this paper is to explore the perception and changes in the fear-avoidance beliefs of physiotherapy students participating in a developed blended learning course on stratified care.
Methodology: A mixed-methods with a convenient sample of two consecutive cohorts were given a blended learning course on stratified care for patients with low back pain. The blended learning course comprised scientific rudiments and application of stratified care in clinical practice conceptualised using the KERN’ 6-step approach. The exam scores, perceptions, performance on self-reflection-tests and pre- and post-scores on The Tampa Scale for Kinesiophobia for Physiotherapists’ (TSK-PT) were obtained. After gaining clinical experience, participants were invited to discuss their clinical experiences and perceptions in workshops. The quantitative data was analysed explorative-descriptively. The qualitative data was analysed following an inductive coding system with constant comparisons.
Results: Ninety-one participants consented to the evaluation (mean age = 22.9 ± 1.6 years), 66% were female. Exam scores correlated with time spent in training (r = 0.30) and scores on self-reflection-tests 1 and 2 (r = 0.40 and r = 0.41). Participants in both cohorts described the learning resources as promoting their interest in the subject (72% and 94%), up-to-date (91% and 93%) and helpful (91% and 97%). The fear-avoidance scores for participants decreased from 53.5 (± 9.96) to 40.1 (± 12.4) with a large effect size (d = 1.18). The regression model [F (2, 49) = 1151.2, p < 0.001] suggests that pre-TSK-PT and the interest of participants in the training predicted post-TSK-PT. The workshop participants (n = 62) all worked in clinical practice. Emerging from the analysis were 4 categories (evolving to maturity in practice, perceiving determinants of stratified care, strategising for implementation and adopting an outlook for future practice).
Conclusion: The quality of engagement in learning, training strategy and interest in the subject contributes immensely to learning outcomes. This blended learning course was successful in reducing kinesiophobia and influencing the participants’ attitude towards care with the potential of being translated into long-term practice.
Die Erstellung von technischen Gebäudebestandsaufnahmen im Rahmen von Sanierungsfahrplänen bei der Ingenieurgesellschaft TRAGWERK in Trier erfolgt derzeit handschriftlich auf mehrseitigen PDF-Checklisten. Die handschriftliche Erfassung bringt jedoch den Nachteil mit sich, dass die Notizen in einer Nachbereitungsphase im Büro in eine digitale Form überführt werden, was zeitaufwändig ist. Ebenso führen die handschriftlich ausgefüllten Checklisten teilweise zu ungenauen und unvollständigen Bestandsaufnahmen und erschweren die Zusammenarbeit mehrerer Mitarbeiter an einem Projekt. Das Ziel dieser Bachelorarbeit ist die Entwicklung eines offline-fähigen Softwaresystems zur digitalen Erstellung von technischen Gebäudebestandsaufnahmen. Diese Lösung soll die beschriebenen Probleme eliminieren, die Nutzungsanforderungen erfüllen und nach Abschluss der Arbeit im Arbeitsalltag des Praxispartners verwendet werden können. Um dieses Ziel zu erreichen, wird ein nutzerzentriertes, iteratives Entwicklungsvorgehen angewendet. Durch Feldstudien zur Analyse des Arbeitsablaufs und der Durchführung einer Nutzungskontextanalyse werden Nutzungsanforderungen an die Software abgeleitet. Ein Konzept in Form von Wireframes unterstützt die Implementierung, die schrittweise durch formative Nutzungstests evaluiert und verbessert wird. Die Nutzungskontextanalyse ergab, dass die Mitarbeiter und zukünftigen Nutzer der Software in zwei rollenbasierte Benutzergruppen eingeteilt werden können: Datenerfasser, die vor Ort offline mit einem iPad arbeiten, und Projektbearbeiter, die im Büro am PC den Sanierungsfahrplan erstellen. Die Evaluation durch Nutzungstests zeigte, dass die entwickelte Web- und iOS-App die Effizienz des Prozesses durch strukturierte digitale Formulare mit Handschrifterkennung, Auswahlfeldern, duplizierbaren Formulargruppen und bedingten Feldern erhöht. Dies verbessert die Vollständigkeit und Genauigkeit der Datenerfassung, beschleunigt die Projektbearbeitung im Büro und erleichtert die Zusammenarbeit mehrerer Mitarbeiter an einem Projekt.
This article discusses ethics in times of pandemic crisis (COVID-19) taking into consideration the sustainability paradigm. Two related ethical approaches are discussed and contrasted. On the one hand, the relational embodied ethics of the commons is discussed in the background of the pandemic of COVID-19. On the other hand, "lifeboat ethics" is interpreted in considering the pandemic situation. The main goal of the article is to compare the two ethical approaches as a way of dealing with our shared predicament in times of a pandemic, a state of exception, and based on that, to additionally derive conclusions about their application in further crises in the Anthropocene, whereby the primacy of sustainability is presumed.
Background: Stratified care approach involving use of the STarT-Back tool to optimise care for patients with low back pain is gaining widespread attention in western countries. However, adoption and implementation of this approach in low-and-middle-income countries will be restricted by context-specific factors that need to be addressed. This study aimed to develop with physiotherapists, tailored intervention strategies for the implementation of stratified care for patients with low back pain.
Methods: A two-round web-based Delphi survey was conducted among purposively sampled physiotherapists with a minimum of three years of clinical experience, with post-graduation certification or specialists. Thirty statements on barriers and enablers for implementation were extracted from the qualitative phase. Statements were rated by a Delphi panel with additional open-ended feedback. After each Delphi round, participants received feedback which informed their subsequent responses. Additional qualitative feedback were analysed using qualitative content analysis. The criteria for consensus and stability were pre-determined using percentage agreement (≥ 75%), median value (≥ 4), Inter-quartile range (≤ 1), and Wilcoxon matched-pairs test respectively.
Results: Participants in the first round were 139 and 125 of them completed the study, yielding a response rate of 90%. Participants were aged 35.2 (SD6.6) years, and 55 (39.6%) were female. Consensus was achieved in 25/30 statements. Wilcoxon’s test showed stability in responses after the 5 statements failed to reach consensus: ‘translate the STarT-Back Tool to pidgin language’ 71% (p = 0.76), ‘begin implementation with government hospitals’ 63% (p = 0.11), ‘share knowledge with traditional bone setters’ 35% (p = 0.67), ‘get second opinion on clinician’s advice’ 63% (p = 0.24) and ‘carry out online consultations’ 65% (p = 0.41). Four statements strengthened by additional qualitative data achieved the highest consensus: ‘patient education’ (96%), ‘quality improvement appraisals’ (96%), ‘undergraduate training on psychosocial care’ (96%) and ‘patient-clinician communication’ (95%).
Conclusion: There was concordance of opinion that patients should be educated to correct misplaced expectations and proper time for communication is vital to implementation. This communication should be learned at undergraduate level, and for already qualified clinicians, quality improvement appraisals are key to sustained and effective care. These recommendations provide a framework for future research on monitored implementation of stratified care in middle-income countries.
In der seit 2009 andauernden Niedrigzinsphase ging der Anteil der Kapitaleinkommen am Volkseinkommen zurück. Da sich der Anteil des Faktors Arbeit nicht wesentlich veränderte, gewann der Produktionsfaktor Boden an Bedeutung. In der Volkswirtschaftlichen Gesamtrechnung spiegelt sich dies jedoch nicht wider, da der Boden dort nicht gesondert ausgewiesen wird. Mithilfe des Henry-George-Theorems wird versucht, eine Methode zu entwickeln, die den Anteil des Faktors Boden quantifiziert. Der explizite Ausweis des Bodeneinkommens in der Volkswirtschaftlichen Gesamtrechnung könnte dazu beitragen, die Rolle dieses vernachlässigten Faktors zu korrigieren.
This paper describes the project “Visual Knowledge Communication”, a joint project that started recently. The partners are psychologists and computer scientists from four universities of the German state Rhineland-Palatinate. The starting point for the project was the fact that visualizations have attracted considerable interest in psychology as well as computer science within the last years. However, psychologists and computer scientists pursued their investigations independently from each other in the past. This project has as its main goal the support and fostering of cooperation between psychologists and computer scientists in several visualization research projects.
The paper sketches the overall project. It then discusses in more detail the authors' subproject which deals with a peer review process for animations developed by students. The basic ideas, the main goals, and the project plan are described.
This paper is a work-in-progress report. Therefore, it does not contain any results.
This article investigates the representation of the issue of refugees travelling to the Italian coast that was reported by two major Italian newspapers between August 8th and August 19th, 2017. Using analysis tools belonging to communication theory and cognitive sciences, i.e. the concepts of frame and attitude, this article highlights two major points: firstly, the analysis reveals how the two newspapers aimed at establishing a specific relationship with their readers on this topic in the relevant period on the basis of specific interpretative models; secondly, each of these interpretative models relies on the representation of specific emotions which play a central role in the interpretation of reality according to a characteristic facet of the definition of post-truth.
We present the concrete realization of a virtual laboratory equipped with a pedagogical agent. Its functionality and media didactics takes into account the results of an usability test on a prototype system, and the students' demand on such an automated assistance as obtained from a preliminary survey. The pedagogical agent mediates between the content and the learner by activating him or her. To provide information about the learner's skills, we propose a pragmatic and simplified competence model that is based on fundamental representations in physics (experiment, figure, text and equation). Moreover, an automated feedback relates the student's self-assessment with the submitted answer to the correctness of the respective task. In consequence, the pedagogical agent enables mental reflection for a crucial review of the own learning process. Interestingly, learning pathways can be envisioned, thus, giving valuable insight into individual strengths and weaknesses.
One key for successful and fluent human-robot-collaboration in disassembly processes is equipping the robot system with higher autonomy and intelligence. In this paper, we present an informed software agent that controls the robot behavior to form an intelligent robot assistant for disassembly purposes. While the disassembly process first depends on the product structure, we inform the agent using a generic approach through product models. The product model is then transformed to a directed graph and used to build, share and define a coarse disassembly plan. To refine the workflow, we formulate "the problem of loosening a connection and the distribution of the work" as a search problem. The created detailed plan consists of a sequence of actions that are used to call, parametrize and execute robot programs for the fulfillment of the assistance. The aim of this research is to equip robot systems with knowledge and skills to allow them to be autonomous in the performance of their assistance to finally improve the ergonomics of disassembly workstations.
Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.
Research integrity (RI) has been a focus of society in recent years as a means to create and to keep trust in science. Higher education institutions (HEIs) play a key role in promoting a culture of RI and responsible conduct of research (RCR). The understanding and practice of RI can vary across cultures. This article aims to outline initial insights into university students’ RI mindsets based on five RI facets: understanding, importance, value-action gap, enforcement approaches, and training. A qualitative exploratory cross-cultural study was conducted with participants from Germany and Bulgaria via semi-structured guided group interviews. An explicit transcultural agreement regarding the significance of RI was categorically indicated. Intercultural differences between the two European countries were revealed and discussed in reference to understanding RI, the value-action gap, enforcement approaches, and training preferences.
Background: Deficiency in musculoskeletal imaging (MI) education will pose a great challenge to physiotherapists in clinical decision making in this era of first-contact physiotherapy practices in many developed and developing countries. This study evaluated the nature and the level of MI training received by physiotherapists who graduate from Nigerian universities.
Methods: An online version of the previously validated Physiotherapist Musculoskeletal Imaging Profiling Questionnaire (PMIPQ) was administered to all eligible physiotherapists identified through the database of the Medical Rehabilitation Therapist Board of Nigeria. Data were obtained on demographics, nature, and level of training on MI procedures using the PMIPQ. Logistic regression, Friedman’s analysis of variance (ANOVA) and Kruskal-Wallis tests were used for the statistical analysis of collected data.
Results: The results (n = 400) showed that only 10.0% of the respondents had a stand-alone entry-level course in MI, 92.8% did not have any MI placement during their clinical internship, and 67.3% had never attended a MI workshop. There was a significant difference in the level of training received across MI procedures [χ2 (15) = 1285.899; p = 0.001]. However, there was no significant difference in the level of MI training across institutions of entry-level programme (p = 0.36). The study participants with transitional Doctor of Physiotherapy education were better trained in MI than their counterparts with a bachelor’s degree only (p = 0.047).
Conclusions: Most physiotherapy programmes in Nigeria did not include a specific MI module; imaging instructions were mainly provided through clinical science courses. The overall self-reported level of MI training among the respondents was deficient. It is recommended that stand-alone MI education should be introduced in the early part of the entry-level physiotherapy curriculum.
Background: The extramuscular connective tissue (ECT) has been shown to play a significant role in mechanical force transmission between musculoskeletal structures. Due to this and owing to its tight connection with the underlying muscle, the ECT may be vulnerable to excessive loading. The present study aimed to investigate the effect of eccentric elbow flexor exercise on the morphology of the biceps brachii ECT. In view of the high nociceptive capacity of the ECT, an additional objective was to elucidate the potential relationship between ECT damage and the occurrence of delayed onset muscle soreness (DOMS).
Methods: Eleven healthy participants (♂ = 7; 24 ± 2 years) performed fatiguing dumbbell elbow flexor eccentric exercise (EE) for one arm and concentric exercise (CE) for the other arm in random order and with random arm allocation. Before, immediately after and 24–96 h post-exercise, maximal voluntary isometric contraction torque of the elbow flexors (dynamometer), pressure pain (algometer), palpation pain (100 mm visual analog scale), biceps brachii ECT thickness and ECT/muscle mobility during passive movement (both high-resolution ultrasound) were examined.
Results: Palpation pain, suggestive of DOMS, was greater after EE than CE, and maximal voluntary isometric contraction torque decreased greater after EE than CE (p < .05). Relative to CE, EE increased ECT thickness at 48 (+ 17%), 72 (+ 14%) and 96 (+ 15%) hours post-exercise (p < .05). At 96 h post-EE, the increase in ECT thickness correlated with palpation pain (r = .68; p < .05). ECT mobility was not different between conditions, but compared to CE, muscle displacement increased at 24 (+ 31%), 72 (+ 31%) and 96 (+ 41%) hours post-EE (p < .05).
Conclusion: Collectively, these results suggest an involvement of the ECT changes in delayed onset muscle soreness.
In Deutschland findet die Gestaltung von Erbbaurechtsverträgen sehr oft unter politischen Gesichtspunkten, aber wenig am Markt orientiert statt. Die Akzeptanz des Erbbaurechts leidet hierunter. Eine wichtige Rolle spielt dabei die Festlegung des Erbbauzinses, der angesichts des niedrigen Zinsniveaus oft als unangemessen empfunden wird. Andererseits stellt sich die Ableitung „marktgerechter“ Erbbauzinsen im Vergleichswege schwierig dar. Im Beitrag wird daher ein praxisbezogener, auf der Kapitalmarkttheorie basierender Ansatz für die Festlegung marktgerechter Erbbauzinsen dargestellt. Wichtig ist dabei die Verschiebung der Rendite/Risiko-Position, die sich aufgrund der Bestellung von Erbbaurechten gegenüber Volleigentum ergibt. Sowohl der Erbbauverpflichtete wie auch der Erbbauberechtigte dürfen sich diesbezüglich nicht schlechter als bei Volleigentum stellen. Diese Anforderung wird durch die Sharpe Ratio konkretisiert. Damit sich der Erbbauberechtigte nicht gegenüber Volleigentum verschlechtert, bedarf es einer „Subventionierung“ seiner Rendite. Es wird gezeigt, dass dies durch den Erbbauberechtigten ohne Einbußen in seiner Rendite/Risiko-Position gegenüber Volleigentum geschehen kann. Auf Grundlage dieser Überlegungen werden Mindestrenditeforderungen für den Erbbauberechtigten und Höchstsätze für den Erbbauverpflichteten kalkuliert, die sich auf die Bodenwerte beziehen.