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Die berufliche Orientierung von Kindern im Grundschulalter ist bislang nur in Ansätzen erforscht. Gleichwohl gibt es berufsorientierende Angebote, die auf verschiedenen Ebenen Grundschulkinder adressieren. Die Untersuchung fokussiert aktuelle Forschungsergebnisse, ausgewählte Initiativen, Kinderbücher, Unterrichtsmaterialien usw. zur beruflichen Orientierung von Kindern. Mit dem Ziel der Entwicklung und Ausdifferenzierung eines facettenreichen beruflichen Selbstkonzeptes von Kindern werden spezifische Forschungs- und Entwicklungspotenziale aufgezeigt.
Nonribosomal peptides (NRP) are crucial molecular mediators in microbial ecology and provide indispensable drugs. Nevertheless, the evolution of the flexible biosynthetic machineries that correlates with the stunning structural diversity of NRPs is poorly understood. Here, we show that recombination is a key driver in the evolution of bacterial NRP synthetase (NRPS) genes across distant bacterial phyla, which has guided structural diversification in a plethora of NRP families by extensive mixing andmatching of biosynthesis genes. The systematic dissection of a large number of individual recombination events did not only unveil a striking plurality in the nature and origin of the exchange units but allowed the deduction of overarching principles that enable the efficient exchange of adenylation (A) domain substrates while keeping the functionality of the dynamic multienzyme complexes. In the majority of cases, recombination events have targeted variable portions of the A(core) domains, yet domain interfaces and the flexible A(sub) domain remained untapped. Our results strongly contradict the widespread assumption that adenylation and condensation (C) domains coevolve and significantly challenge the attributed role of C domains as stringent selectivity filter during NRP synthesis. Moreover, they teach valuable lessons on the choice of natural exchange units in the evolution of NRPS diversity, which may guide future engineering approaches.
Die Untersuchung befasst sich mit den umstrittenen Grenzen des Betrugs durch Unterlassen und schafft Klarheit für die Praxis, indem die dogmatischen Leitlinien der Rechtsprechung offengelegt werden. Im Zentrum steht dabei die Interpretation der betrugsspezifischen Garantenstellung durch die Judikatur. Nachdem diese sich im Ergebnis nicht mit der vermeintlich vorherrschenden Rechtsquellentrias aus Gesetz, Vertrag und Ingerenz erklären lässt, wird anhand einer eingehenden Durchsicht der gesamten Betrugsrechtsprechung der Vertrauensgedanke als materielles Kriterium herausgearbeitet und konturiert. Ob hiermit die gesetzgeberische Lücke in § 13 Abs. 1 StGB tatsächlich auf angemessene Art geschlossen wurde, wird abschließend kritisch besprochen.
One third of the world's population lives in areas where earthquakes causing at least slight damage are frequently expected. Thus, the development and testing of global seismicity models is essential to improving seismic hazard estimates and earthquake-preparedness protocols for effective disaster-risk mitigation. Currently, the availability and quality of geodetic data along plate-boundary regions provides the opportunity to construct global models of plate motion and strain rate, which can be translated into global maps of forecasted seismicity. Moreover, the broad coverage of existing earthquake catalogs facilitates in present-day the calibration and testing of global seismicity models. As a result, modern global seismicity models can integrate two independent factors necessary for physics-based, long-term earthquake forecasting, namely interseismic crustal strain accumulation and sudden lithospheric stress release.
In this dissertation, I present the construction of and testing results for two global ensemble seismicity models, aimed at providing mean rates of shallow (0-70 km) earthquake activity for seismic hazard assessment. These models depend on the Subduction Megathrust Earthquake Rate Forecast (SMERF2), a stationary seismicity approach for subduction zones, based on the conservation of moment principle and the use of regional "geodesy-to-seismicity" parameters, such as corner magnitudes, seismogenic thicknesses and subduction dip angles. Specifically, this interface-earthquake model combines geodetic strain rates with instrumentally-recorded seismicity to compute long-term rates of seismic and geodetic moment. Based on this, I derive analytical solutions for seismic coupling and earthquake activity, which provide this earthquake model with the initial abilities to properly forecast interface seismicity. Then, I integrate SMERF2 interface-seismicity estimates with earthquake computations in non-subduction zones provided by the Seismic Hazard Inferred From Tectonics based on the second iteration of the Global Strain Rate Map seismicity approach to construct the global Tectonic Earthquake Activity Model (TEAM). Thus, TEAM is designed to reduce number, and potentially spatial, earthquake inconsistencies of its predecessor tectonic earthquake model during the 2015-2017 period. Also, I combine this new geodetic-based earthquake approach with a global smoothed-seismicity model to create the World Hybrid Earthquake Estimates based on Likelihood scores (WHEEL) model. This updated hybrid model serves as an alternative earthquake-rate approach to the Global Earthquake Activity Rate model for forecasting long-term rates of shallow seismicity everywhere on Earth.
Global seismicity models provide scientific hypotheses about when and where earthquakes may occur, and how big they might be. Nonetheless, the veracity of these hypotheses can only be either confirmed or rejected after prospective forecast evaluation. Therefore, I finally test the consistency and relative performance of these global seismicity models with independent observations recorded during the 2014-2019 pseudo-prospective evaluation period. As a result, hybrid earthquake models based on both geodesy and seismicity are the most informative seismicity models during the testing time frame, as they obtain higher information scores than their constituent model components. These results support the combination of interseismic strain measurements with earthquake-catalog data for improved seismicity modeling. However, further prospective evaluations are required to more accurately describe the capacities of these global ensemble seismicity models to forecast longer-term earthquake activity.
Kämpfe mit Marx
(2021)
Die Wiederentdeckung des Marxismus durch die Neue Linke: eine spannungsvolle Geschichte.Schon vor 1968, in den 1950er Jahren, entstand eine Neue Linke. Junge akademische Intellektuelle begannen jenseits der polarisierten traditionellen Arbeiterbewegung nach neuen Anknüpfungspunkten für ein linkes Denken zu suchen. Neu gegründete Theoriezeitschriften wurden dabei zu ihren Organisationskernen. In der Theorie fand die Neue Linke gemeinsame Überzeugungen und verschmolz auch hierdurch zu einer vorgestellten Gemeinschaft. Insbesondere marxistische Theorien wurden wiederentdeckt und neu interpretiert.Mit Marx führte die Neue Linke gemeinsame Kämpfe gegen eine »bürgerliche« Öffentlichkeit - mit Marx trug sie aber auch immer stärker Kämpfe untereinander aus. David Bebnowski nutzt die beiden West-Berliner Zeitschriften »Das Argument« und »PROKLA« als Seismographen und Sonden zur Ergründung der Geschichte der Neuen Linken und des akademischen Marxismus. Dabei wird deutlich, dass »1968« nicht nur für Aufbrüche steht, sondern ebenso zu Spaltungen führte, die die Linke bis heute kennzeichnen.
The mean free path of ionizing photons, lambda(mfp), is a key factor in the photoionization of the intergalactic medium (IGM). At z greater than or similar to 5, however, lambda(mfp) may be short enough that measurements towards QSOs are biased by the QSO proximity effect. We present new direct measurements of lambda(mfp) that address this bias and extend up to z similar to 6 for the first time. Our measurements at z similar to 5 are based on data from the Giant Gemini GMOS survey and new Keck LRIS observations of low-luminosity QSOs. At z similar to 6 we use QSO spectra from Keck ESI and VLT X-Shooter. We measure lambda(mfp) = 9.09(-1.28)(+1.62) proper Mpc and 0.75(-0.45)(+0.65) proper Mpc (68 percent confidence) at z = 5.1 and 6.0, respectively. The results at z = 5.1 are consistent with existing measurements, suggesting that bias from the proximity effect is minor at this redshift. At z = 6.0, however, we find that neglecting the proximity effect biases the result high by a factor of two or more. Our measurement at z = 6.0 falls well below extrapolations from lower redshifts, indicating rapid evolution in lambda(mfp) over 5 < z < 6. This evolution disfavours models in which reionization ended early enough that the IGM had time to fully relax hydrodynamically by z = 6, but is qualitatively consistent with models wherein reionization completed at z = 6 or even significantly later. Our mean free path results are most consistent with late reionization models wherein the IGM is still 20 percent neutral at z = 6, although our measurement at z = 6.0 is even lower than these models prefer.
Infection is a common and often deadly complication after burn injury. A major underlying factor is burn-induced immune dysfunction, particularly with respect to neutrophils as the primary responders to infection. Temporally after murine scald injury, we demonstrate impaired bone marrow neutrophil chemotaxis toward CXCL1 ex vivo. Additionally, we observed a reduced recruitment of neutrophils to the peritoneal after elicitation 7 days after injury. We demonstrate that neutrophil ceramide levels increase after burn injury, and this is associated with decreased expression of CXCR2 and blunted chemotaxis. A major signaling event upon CXCR2 activation is Akt phosphorylation and this was reduced when ceramide was elevated. In contrast, PTEN levels were elevated and PTEN-inhibition elevated phospho-Akt levels and mitigated the burn-induced neutrophil chemotaxis defect. Altogether, this study identifies a newly described pathway of ceramide-mediated suppression of neutrophil chemotaxis after burn injury and introduces potential targets to mitigate this defect and reduce infection-related morbidity and mortality after burn.
A characterization of the essential spectrum of Schrodinger operators on infinite graphs is derived involving the concept of R-limits. This concept, which was introduced previously for operators on N and Z(d) as "right-limits," captures the behaviour of the operator at infinity. For graphs with sub-exponential growth rate, we show that each point in sigma(ss)(H) corresponds to a bounded generalized eigenfunction of a corresponding R-limit of H. If, additionally, the graph is of uniform sub-exponential growth, also the converse inclusion holds.
With recent experimental advances in laser-driven electron dynamics in polyatomic molecules, the need arises for their reliable theoretical modelling. Among efficient, yet fairly accurate methods for many-electron dynamics are Time-Dependent Configuration Interaction Singles (TD-CIS) (a Wave Function Theory (WFT) method), and Real-Time Time-Dependent Density Functional Theory (RT-TD-DFT), respectively. Here we compare TD-CIS combined with extended Atomic Orbital (AO) bases, TD-CIS/AO, with RT-TD-DFT in a grid representation of the Kohn-Sham orbitals, RT-TD-DFT/Grid. Possible ionization losses are treated by complex absorbing potentials in energy space (for TD-CIS/AO) or real space (for RT-TD-DFT), respectively. The comparison is made for two test cases: (i) state-to-state transitions using resonant lasers (pi-pulses), i.e., bound electron motion, and (ii) large-amplitude electron motion leading to High Harmonic Generation (HHG). Test systems are a H-2 molecule and cis- and trans-1,2-dichlorethene, C2H2Cl2, (DCE). From time-dependent electronic energies, dipole moments and from HHG spectra, the following observations are made: first, for bound state-to-state transitions enforced by pi-pulses, TD-CIS nicely accounts for the expected population inversion in contrast to RT-TD-DFT, in agreement with earlier findings. Secondly, when using laser pulses under non-resonant conditions, dipole moments and lower harmonics in HHG spectra are obtained by TD-CIS/AO which are in good agreement with those obtained with RT-TD-DFT/Grid. Deviations become larger for higher harmonics and at low laser intensities, i.e., for low-intensity HHG signals. We also carefully test effects of basis sets for TD-CIS/AO and grid size for RT-TD-DFT/Grid, different exchange-correlation functionals in RT-TD-DFT, and absorbing boundaries. Finally, for the present examples, TD-CIS/AO is observed to be at least an order of magnitude more computationally efficient than RT-TD-DFT/Grid.
The chemical nature, the number length of integrated building blocks, as well as their sequence structure impact the phase morphology of multiblock copolymers (MBC) consisting of two non-miscible block types. We hypothesized that a strictly alternating sequence should favour phase segregation and in this way the elastic properties. A library of well-defined MBCs composed of two different hydrophobic, semi-crystalline blocks providing domains with well-separated melting temperatures (T(m)s) were synthesized from the same type of precursor building blocks as strictly alternating (MBCsalt) or random (MBCsran) MBCs and compared. Three different series of MBCsalt or MBCsran were synthesized by high-throughput synthesis by coupling oligo(e-caprolactone) (OCL) of different molecular weights (2, 4, and 8 kDa) with oligotetrahydrofuran (OTHF, 2.9 kDa) via Steglich esterification in which the molar ratio of the reaction partners was slightly adjusted. Maximum of weight average molecular weight (M-w) were 65,000 g center dot mol(-1), 165,000 g center dot mol(-1), and 168,000 g center dot mol(-1) for MBCsalt and 80,500 g center dot mol(-1), 100,000 g center dot mol(-1), and 147,600 g center dot mol(-1) for MBCsran. When Mw increased, a decrease of both Tms associated to the melting of the OCL and OTHF domains was observed for all MBCs. T-m (OTHF) of MBCsran was always higher than Tm (OTHF) of MBCsalt, which was attributed to a better phase segregation. In addition, the elongation at break of MBCsalt was almost half as high when compared to MBCsran. In this way this study elucidates role of the block length and sequence structure in MBCs and enables a quantitative discussion of the structure-function relationship when two semi-crystalline block segments are utilized for the design of block copolymers.
The chemical nature, the number length of integrated building blocks, as well as their sequence structure impact the phase morphology of multiblock copolymers (MBC) consisting of two non-miscible block types. It is hypothesized that a strictly alternating sequence should impact phase segregation. A library of well-defined MBC obtained by coupling oligo(epsilon-caprolactone) (OCL) of different molecular weights (2, 4, and 8 kDa) with oligotetrahydrofuran (OTHF, 2.9 kDa) via Steglich esterification results in strictly alternating (MBCalt) or random (MBCran) MBC. The three different series has a weight average molecular weight (M-w) of 65 000, 165 000, and 168 000 g mol(-1) for MBCalt and 80 500, 100 000, and 147 600 g mol(-1) for MBCran. When the chain length of OCL building blocks is increased, the tendency for phase segregation is facilitated, which is attributed to the decrease in chain mobility within the MBC. Furthermore, it is found that the phase segregation disturbs the crystallization by causing heterogeneities in the semi-crystalline alignment, which is attributed to an increase of the disorder of the OCL semi-crystalline alignment.
Background
Static stretching (SS) can impair performance and increase range of motion of a non-exercised or non-stretched muscle, respectively. An underdeveloped research area is the effect of unilateral stretching on non-local force output.
Objective
The objective of this review was to describe the effects of unilateral SS on contralateral, non-stretched, muscle force and identify gaps in the literature.
Methods
A systematic literature search following preferred reporting items for systematic review and meta-analyses Protocols guidelines was performed according to prescribed inclusion and exclusion criteria. Weighted means and ranges highlighted the non-local force output response to unilateral stretching. The physiotherapy evidence database scale was used to assess study risk of bias and methodological quality.
Results
Unilateral stretching protocols from six studies involved 6.3 +/- 2 repetitions of 36.3 +/- 7.4 s with 19.3 +/- 5.7 s recovery between stretches. The mean stretch-induced force deficits exhibited small magnitude effect sizes for both the stretched (-6.7 +/- 7.1%, d = -0.35: 0.01 to -1.8) and contralateral, non-stretched, muscles (-4.0 +/- 4.9%, d = , 0.22: 0.08 to 1.1). Control measures exhibited trivial deficits.
Conclusion
The limited literature examining non-local effects of prolonged SS revealed that both the stretched and contralateral, non-stretched, limbs of young adults demonstrate small magnitude force deficits. However, the frequency of studies with these effects were similar with three measures demonstrating deficits, and four measures showing trivial changes. These results highlight the possible global (non-local) effects of prolonged SS. Further research should investigate effects of lower intensity stretching, upper versus lower body stretching, different age groups, incorporate full warm-ups, and identify predominant mechanisms among others.
Introduction
(2021)
Confidence Counts
(2021)
The increasing reliance on online learning in higher education has been further expedited by the on-going Covid-19 pandemic. Students need to be supported as they adapt to this new learning environment. Research has established that learners with positive online learning self-efficacy beliefs are more likely to persevere and achieve their higher education goals when learning online. In this paper, we explore how MOOC design can contribute to the four sources of self-efficacy beliefs posited by Bandura [4]. Specifically, we will explore, drawing on learner reflections, whether design elements of the MOOC, The Digital Edge: Essentials for the Online Learner, provided participants with the necessary mastery experiences, vicarious experiences, verbal persuasion, and affective regulation opportunities, to evaluate and develop their online learning self-efficacy beliefs. Findings from a content analysis of discussion forum posts show that learners referenced three of the four information sources when reflecting on their experience of the MOOC. This paper illustrates the potential of MOOCs as a pedagogical tool for enhancing online learning self-efficacy among students.
We report on the multiple response of microgels triggered by a single optical stimulus. Under irradiation, the volume of the microgels is reversibly switched by more than 20 times. The irradiation initiates two different processes: photo-isomerization of the photo-sensitive surfactant, which forms a complex with the anionic microgel, rendering it photo-responsive; and local heating due to a thermo-plasmonic effect within the structured gold layer on which the microgel is deposited. The photo-responsivity is related to the reversible accommodation/release of the photo-sensitive surfactant depending on its photo-isomerization state, while the thermo-sensitivity is intrinsically built in. We show that under exposure to green light, the thermo-plasmonic effect generates a local hot spot in the gold layer, resulting in the shrinkage of the microgel. This process competes with the simultaneous photo-induced swelling. Depending on the position of the laser spot, the spatiotemporal control of reversible particle shrinking/swelling with a predefined extent on a per-second base can be implemented.
CrashNet
(2021)
Destructive car crash tests are an elaborate, time-consuming, and expensive necessity of the automotive development process. Today, finite element method (FEM) simulations are used to reduce costs by simulating car crashes computationally. We propose CrashNet, an encoder-decoder deep neural network architecture that reduces costs further and models specific outcomes of car crashes very accurately. We achieve this by formulating car crash events as time series prediction enriched with a set of scalar features. Traditional sequence-to-sequence models are usually composed of convolutional neural network (CNN) and CNN transpose layers. We propose to concatenate those with an MLP capable of learning how to inject the given scalars into the output time series. In addition, we replace the CNN transpose with 2D CNN transpose layers in order to force the model to process the hidden state of the set of scalars as one time series. The proposed CrashNet model can be trained efficiently and is able to process scalars and time series as input in order to infer the results of crash tests. CrashNet produces results faster and at a lower cost compared to destructive tests and FEM simulations. Moreover, it represents a novel approach in the car safety management domain.
The existential threat to small businesses, based on their crucial role in the economy, is behind the plethora of scholarly studies in 2020, the first year of the COVID-19 pandemic. Examining the 15 contributions of the special issue on the “Economic effects of the COVID-19 pandemic on entrepreneurship and small businesses,” the paper comprises four parts: a systematic review of the literature on the effect on entrepreneurship and small businesses; a discussion of four literature strands based on this review; an overview of the contributions in this special issue; and some ideas for post-pandemic economic research.
"BreaThink"
(2021)
Cognition is shaped by signals from outside and within the body. Following recent evidence of interoceptive signals modulating higher-level cognition, we examined whether breathing changes the production and perception of quantities. In Experiment 1, 22 adults verbally produced on average larger random numbers after inhaling than after exhaling. In Experiment 2, 24 further adults estimated the numerosity of dot patterns that were briefly shown after either inhaling or exhaling. Again, we obtained on average larger responses following inhalation than exhalation. These converging results extend models of situated cognition according to which higher-level cognition is sensitive to transient interoceptive states.
Carbonate minerals are common in both marine and lacustrine records, and are frequently used for paleoenvironmental reconstructions. The sedimentary sequence of the endorheic Dead Sea and its precursors contain aragonite laminae that provide a detailed sedimentary archive of climatic, hydrologic, limnologic and environmental conditions since the Pleistocene. However, the interpretation of these archives requires a detailed understanding of the constraints and mechanisms affecting CaCO3 precipitation, which are still debated. The implications of aragonite precipitation in the Dead Sea and in its late Pleistocene predecessor (Lake Lisan) were investigated in this study by mixing natural and synthetic brines with a synthetic bicarbonate solution that mimics flash-floods composition, with and without the addition of extracellular polymeric substances (EPS). Aragonite precipitation was monitored, and precipitation rates and carbonate yields were calculated and are discussed with respect to modern aquatic environments. The experimental insights on aragonite precipitation are then integrated with microfacies analyses in order to reconstruct and constrain prevailing limnogeological processes and their hydroclimatic drivers under low (interglacial) and high (glacial) lake level stands. Aragonite precipitation took place within days to several weeks after the mixing of the brines with a synthetic bicarbonate solution. Incubation time was proportional to bicarbonate concentration, and precipitation rates were partially influenced by ionic strength. Additionally, extracellular polymeric substances inhibited aragonite precipitation for several months. As for the lake's water budget, our calculations suggest that the precipitation of a typical aragonite lamina (0.5 mm thick) during high lake stand requires unreasonable freshwater inflow from either surface or subsurface sources. This discrepancy can be resolved by considering one or a combination of the following scenarios; (1) discontinuous aragonite deposition over parts of the lake floor; (2) supply of additional carbonate flux (or fluxes) to the lake from aeolian dust and the remobilization and dissolution of dust deposits at the watershed; (3) carbonate production via oxidation of organic carbon by sulfate-reducing bacteria. Altogether, it is suggested that aragonite laminae thickness cannot be directly interpreted for quantitatively reconstructing the hydrological balance for the entire lake, they may still prove valuable for identifying inherent hydroclimatic periodicities at a single site.
Digital software platforms such as iOS or Android evolve quickly. Through regular updates, their set of built-in (core) features increases. While innovation allows strengthening platforms amidst competition, it can hurt contributors when introducing core features that are already provided by third-party developers (Platform Coring).
This book addresses the underexplored phenomenon of Platform Coring and provides strategical guidance for platform owners and third-party contributors. Platform owners are well-advised to carefully consider the benefits and risks for their platform ecosystem.
The book contributes by highlighting avenues to employ Platform Coring for the competitive advantage of the platform and ecosystem simultaneously.
Future ERP Systems
(2021)
This paper presents a research agenda on the current generation of ERP systems which was developed based on a literature review on current problems of ERP systems. The problems are presented following the ERP life cycle. In the next step, the identified problems are mapped on a reference architecture model of ERP systems that is an extension of the three-tier architecture model that is widely used in practice. The research agenda is structured according to the reference architecture model and addresses the problems identified regarding data, infrastructure, adaptation, processes, and user interface layer.
Today’s mobile devices are part of powerful business ecosystems, which usually involve digital platforms. To better understand the complex phenomenon of coring and related dynamics, this paper presents a case study comparing iMessage as part of Apple’s iOS and WhatsApp. Specifically, it investigates activities regarding platform coring, as the integration of several functionalities provided by third-party applications in the platform core. The paper makes three contributions. First, a systematization of coring activities is developed. Coring modes are differentiated by the amount of coring and application maintenance. Second, the case study revealed that the phenomenon of platform coring is present on digital platforms for mobile devices. Third, the fundamentals of coring are discussed as a first step towards theoretical development. Even though coring constitutes a potential threat for third-party developers regarding their functional differentiation, an idea of what a beneficial partnership incorporating coring activities could look like is developed here.
The idea of the continuous improvement process (CIP) helps companies to continuously improve their operation and thereby contributes to their competitiveness. Through digi tization, new potentials emerge to solve known CIP issues. This contribution specifically addresses the individual motivation of employees to contribute to the CIP. Typically, related initiatives lack contributions over time. The use of gamification is a promising way to achieve continuous participation by addressing the individual needs of participants. While the use of extrinsic motivation elements is common in practice, the idea of this approach is to specifically address intrinsic motivations which serve as a long-term motivator. This article contributes to a gam-ification concept for the continuous improvement process. The main results include an adapted CIP, a gamification concept, and a market mechanism. Furthermore, the concept is implemented and demonstrated as a prototype in an online platform.
Government as a platform?
(2021)
Digital platforms, by their design, allow the coordination of multiple entities to achieve a common goal. Motivated by the success of platforms in the private sector, they increasingly receive attention in the public sector. However, different understandings of the platform concept prevail. To guide the development and further research a coherent understanding is required. To address this gap, we identify the constitutive elements of platforms in the public sector. Moreover, their potential to coordinate partially autonomous entities as typical for federal organized states is highlighted.
This study contributes through a uniform understanding of public service platforms. Despite constitutive elements, the proposed framework for platforms in the public sector may guide future analysis. The analysis framework is applied to platforms of federal states in the European Union.
Die Digitalisierung des deutschen Mittelstandes schreitet weiterhin schleppend voran. So verfügt zwar ein wachsender Teil dieser Unternehmen über vereinzelte Informations- und Kommunikationssysteme, die zielführende Vernetzung und Integration dieser Systeme stellt jedoch weiterhin eine große Aufgabe dar [1]. Besonders vor dem Hintergrund wachsender Bedürfnisse für Informationen und Transparenz sehen sich Unternehmen zunehmend mit der analyseorientierten Nutzbarmachung der Unternehmensdaten konfrontiert [2].
Software platforms allow for the extension of features by third-party contributors. Thereby, platform innovation is an important aspects of platforms attractiveness for users and complementors. While previous research focused the introduction of new features, the aspect of feature removal and discontinued features on software platforms has been disregarded. To explore the phenomenon and motivations for feature removal on software platforms, a review of recent literature is provided. To illustrate the existence of and motivations for feature removal, a case study of the browser platform Mozilla Firefox is presented. The results reveal feature removal to regularly occur on browser platforms for user- and developer-related features. Frequent reasons for feature removal involve unused features, security concerns, and bugs. Related motivations for feature removal are discussed from the platform owner's perspective. Implications for complementors and users are highlighted.
Software platforms regularly introduce new features to remain competitive. While platform innovation is considered to be a critical success factor, adding certain features could hurt the ecosystem. If platform owners provide functionality that was previously provided by a contributor, the owners enter complementary product spaces. Complementary market entry frequently occurs on software platforms and is a major concern for third-party developers.
Divergent findings on the impact of complementary market entry call for the consideration of additional factors. As prior research neglected the third-party perspective, this contribution aims to address this gap. We explore the use of measures to prevent complementary market entry using a survey approach on browser platforms. The research model is tested with 655 responses among developer from Mozilla Firefox and Google Chrome. To explain countermeasures employment, developer’s attitude and perceived likelihood are important. The results reveal that developers employ countermeasures if complementary market entry is assessed negatively and perceived as likely for their extension. Differences among browser platforms concerning complementary market entry are identified. Product spaces of extensions being available on multiple platforms are less likely to be entered and more heavily protected. Implications for research and stakeholders, i.e. platform owners and contributors are discussed.
Modern browsers are digital software platforms, as they allow third parties to extend functionality by providing extensions. In a highly competitive environment, differentiation through provided functionality is a key factor for browser platforms. As the development of browsers progress, new functions are constantly being released. Browsers could thus enter complementary markets by adding functionality previously provided by third-party extensions, which is referred to as ‘platform coring’. Previous studies have missed the perspective of the parties involved. To address this gap, we conducted interviews with third-party and core developers in the security and privacy domain from Firefox and Chrome. This study provides three contributions. First, insights into stakeholder-specific issues concerning coring. Second, measures to prevent coring. Third, strategical guidance for developers and owners. Third-party vendors experienced and core developers confirmed that coring occurs on browser platforms. While developers with extrinsic motivations assess coring negatively, developers with intrinsic motivations perceive coring positively.
Viper
(2021)
Key-value stores (KVSs) have found wide application in modern software systems. For persistence, their data resides in slow secondary storage, which requires KVSs to employ various techniques to increase their read and write performance from and to the underlying medium. Emerging persistent memory (PMem) technologies offer data persistence at close-to-DRAM speed, making them a promising alternative to classical disk-based storage. However, simply drop-in replacing existing storage with PMem does not yield good results, as block-based access behaves differently in PMem than on disk and ignores PMem's byte addressability, layout, and unique performance characteristics. In this paper, we propose three PMem-specific access patterns and implement them in a hybrid PMem-DRAM KVS called Viper. We employ a DRAM-based hash index and a PMem-aware storage layout to utilize the random-write speed of DRAM and efficient sequential-write performance PMem. Our evaluation shows that Viper significantly outperforms existing KVSs for core KVS operations while providing full data persistence. Moreover, Viper outperforms existing PMem-only, hybrid, and disk-based KVSs by 4-18x for write workloads, while matching or surpassing their get performance.
Viper
(2021)
Key-value stores (KVSs) have found wide application in modern software systems. For persistence, their data resides in slow secondary storage, which requires KVSs to employ various techniques to increase their read and write performance from and to the underlying medium. Emerging persistent memory (PMem) technologies offer data persistence at close-to-DRAM speed, making them a promising alternative to classical disk-based storage. However, simply drop-in replacing existing storage with PMem does not yield good results, as block-based access behaves differently in PMem than on disk and ignores PMem's byte addressability, layout, and unique performance characteristics. In this paper, we propose three PMem-specific access patterns and implement them in a hybrid PMem-DRAM KVS called Viper. We employ a DRAM-based hash index and a PMem-aware storage layout to utilize the random-write speed of DRAM and efficient sequential-write performance PMem. Our evaluation shows that Viper significantly outperforms existing KVSs for core KVS operations while providing full data persistence. Moreover, Viper outperforms existing PMem-only, hybrid, and disk-based KVSs by 4-18x for write workloads, while matching or surpassing their get performance.
In February 2020, the Inter-American Court of Human Rights (IACtHR) delivered a landmark decision in which it held Argentina responsible for the violation of several rights of 132 indigenous communities inhabiting a certain area in the province of Salta. In the Case of the Indigenous Communities of the Lhaka Honhat (Our Land) Association v. Argentina the IACtHR declared for the first time an autonomous violation of the right to a healthy environment and other DESCA (Economic, Social, Cultural and Environmental rights). Thereby, it further developed its case law on the direct justiciability of DESCA on the basis of Article 26 of the American Convention on Human Rights (ACHR) that was first established in Lagos del Campo in 2017. Focusing on the right to a healthy environment and the right to water the authors critically examine how the Court derived the direct justiciability of DESCA. In the following, the contribution examines to what extent the right to a healthy environment has been specified in the current judgment compared to the initial outline of this right by the Court in its Advisory Opinion No. 23. The analysis also deals with the question whether the facts of the case were at all suitable for such a specification and what general value could be added by an autonomous examination of DESCA. Finally, the contribution ends with a mixed conclusion on the significance of the judgment and a thoughtful outlook on the future development of the case law on Art. 26 ACHR.
Trait means or variance
(2021)
One of the few laws in ecology is that communities consist of few common and many rare taxa. Functional traits may help to identify the underlying mechanisms of this community pattern, since they correlate with different niche dimensions. However, comprehensive studies are missing that investigate the effects of species mean traits (niche position) and intraspecific trait variability (ITV, niche width) on species abundance. In this study, we investigated fragmented dry grasslands to reveal trait-occurrence relationships in plants at local and regional scales. We predicted that (a) at the local scale, species occurrence is highest for species with intermediate traits, (b) at the regional scale, habitat specialists have a lower species occurrence than generalists, and thus, traits associated with stress-tolerance have a negative effect on species occurrence, and (c) ITV increases species occurrence irrespective of the scale. We measured three plant functional traits (SLA = specific leaf area, LDMC = leaf dry matter content, plant height) at 21 local dry grassland communities (10 m × 10 m) and analyzed the effect of these traits and their variation on species occurrence. At the local scale, mean LDMC had a positive effect on species occurrence, indicating that stress-tolerant species are the most abundant rather than species with intermediate traits (hypothesis 1). We found limited support for lower specialist occurrence at the regional scale (hypothesis 2). Further, ITV of LDMC and plant height had a positive effect on local occurrence supporting hypothesis 3. In contrast, at the regional scale, plants with a higher ITV of plant height were less frequent. We found no evidence that the consideration of phylogenetic relationships in our analyses influenced our findings. In conclusion, both species mean traits (in particular LDMC) and ITV were differently related to species occurrence with respect to spatial scale. Therefore, our study underlines the strong scale-dependency of trait-abundance relationships.
Trait means or variance
(2021)
One of the few laws in ecology is that communities consist of few common and many rare taxa. Functional traits may help to identify the underlying mechanisms of this community pattern, since they correlate with different niche dimensions. However, comprehensive studies are missing that investigate the effects of species mean traits (niche position) and intraspecific trait variability (ITV, niche width) on species abundance. In this study, we investigated fragmented dry grasslands to reveal trait-occurrence relationships in plants at local and regional scales. We predicted that (a) at the local scale, species occurrence is highest for species with intermediate traits, (b) at the regional scale, habitat specialists have a lower species occurrence than generalists, and thus, traits associated with stress-tolerance have a negative effect on species occurrence, and (c) ITV increases species occurrence irrespective of the scale. We measured three plant functional traits (SLA = specific leaf area, LDMC = leaf dry matter content, plant height) at 21 local dry grassland communities (10 m × 10 m) and analyzed the effect of these traits and their variation on species occurrence. At the local scale, mean LDMC had a positive effect on species occurrence, indicating that stress-tolerant species are the most abundant rather than species with intermediate traits (hypothesis 1). We found limited support for lower specialist occurrence at the regional scale (hypothesis 2). Further, ITV of LDMC and plant height had a positive effect on local occurrence supporting hypothesis 3. In contrast, at the regional scale, plants with a higher ITV of plant height were less frequent. We found no evidence that the consideration of phylogenetic relationships in our analyses influenced our findings. In conclusion, both species mean traits (in particular LDMC) and ITV were differently related to species occurrence with respect to spatial scale. Therefore, our study underlines the strong scale-dependency of trait-abundance relationships.
Starkregen in Berlin
(2021)
In den Sommern der Jahre 2017 und 2019 kam es in Berlin an mehreren Orten zu Überschwemmungen in Folge von Starkregenereignissen. In beiden Jahren führte dies zu erheblichen Beeinträchtigungen im Alltag der Berliner:innen sowie zu hohen Sachschäden. Eine interdisziplinäre Taskforce des DFG-Graduiertenkollegs NatRiskChange untersuchte (1) die meteorologischen Eigenschaften zweier besonders eindrücklicher Unwetter, sowie (2) die Vulnerabilität der Berliner Bevölkerung gegenüber Starkregen.
Eine vergleichende meteorologische Rekonstruktion der Starkregenereignisse von 2017 und 2019 ergab deutliche Unterschiede in der Entstehung und den Überschreitungswahrscheinlichkeiten der beiden Unwetter. So war das Ereignis von 2017 mit einer relativ großen räumlichen Ausdehnung und langer Dauer ein untypisches Starkregenereignis, während es sich bei dem Unwetter von 2019 um ein typisches, kurzzeitiges Starkregenereignis mit ausgeprägter räumlicher Heterogenität handelte. Eine anschließende statistische Analyse zeigte, dass das Ereignis von 2017 für längere Niederschlagsdauern (>=24 h) als großflächiges Extremereignis mit Überschreitungswahrscheinlichkeiten von unter 1 % einzuordnen ist (d.h. Wiederkehrperioden >=100 Jahre). Im Jahr 2019 wurden dagegen ähnliche Überschreitungswahrscheinlichkeiten nur lokal und für kürzere Zeiträume (1-2 h) berechnet.
Die Vulnerabilitätsanalyse basiert auf einer von April bis Juni 2020 in Berlin durchgeführten Onlinebefragung. Diese richtete sich an Personen, die bereits von vergangenen Starkregenereignissen betroffen waren und thematisierte das Schadensereignis selbst, daraus entstandene Beeinträchtigungen und Schäden, Risikowahrnehmung sowie Notfall- und Vorsorgemaßnahmen. Die erhobenen Umfragedaten (n=102) beziehen sich vornehmlich auf die Ereignisse von 2017 und 2019 und zeigen, dass die Berliner Bevölkerung sowohl im Alltag (z.B. bei der Beschaffung von Lebensmitteln) als auch im eigenen Haushalt (z.B. durch Überschwemmungsschäden) von den Unwettern beeinträchtigt war. Zudem deuteten die Antworten der Betroffenen auf Möglichkeiten hin, die Vulnerabilität der Gesellschaft gegenüber Starkregen weiter zu reduzieren - etwa durch die Unterstützung besonders betroffener Gruppen (z.B. Pflegende), durch gezielte Informationskampagnen zum Schutz vor Starkregen oder durch die Erhöhung der Reichweite von Unwetterwarnungen. Eine statistische Analyse zur Effektivität privater Notfall- und Vorsorgemaßnahmen auf Grundlage der Umfragedaten bestätigte vorherige Studienergebnisse.
So gab es Anhaltspunkte dafür, dass durch das Umsetzen von Vorsorgemaßnahmen wie beispielsweise das Installieren von Rückstauklappen, Barriere-Systemen oder Pumpen Starkregenschäden reduziert werden können.
Die Ergebnisse dieses Berichts unterstreichen die Notwendigkeit für ein integriertes Starkregenrisikomanagment, das die Risikokomponenten Gefährdung, Vulnerabilität und Exposition ganzheitlich und auf mehreren Ebenen (z.B. staatlich, kommunal, privat) betrachtet.
Im Zuge der Digitalisierung bietet Business Analytics das Potenzial, die Budgetierung insbesondere durch eine Automatisierung von Prozessschritten der Budgetierung maßgeblich weiterzuentwickeln. Dieser Beitrag zeigt mittels einer empirischen Untersuchung den Status quo des Einsatzes von Business Analytics im Rahmen der Budgetierung in Deutschland und geht auf die Beurteilung einer Automatisierung der Budgetierung durch Unternehmen ein.
Future Outlook and Scenarios
(2021)
Where is local self-government heading in the future? Among trends identified is firstly an intensification of multilevel, intermunicipal, and cross-border governance. In the future even more of cooperation and coordination among different political and administrative levels will be required. Territorial boundaries have become increasingly incongruent with functional public activities. Secondly, the innovative potential of introducing markets as templates for organisational reform has reached its end. Future reforms will most likely try to adapt market reforms to local public contexts, or even reverse the development. Finally, a tightening of state steering and an increased dependence on state funding to uphold local services is expected. Waves of amalgamations might slow down this process but they will not make financial problems disappear completely.
Most image restoration methods in astronomy rely upon probabilistic tools that infer the best solution for a deconvolution problem. They achieve good performances when the point spread function (PSF) is spatially invariant in the image plane.
However, this condition is not always satisfied in real optical systems. We propose a new method for the restoration of images affected by static and anisotropic aberrations using Deep Neural Networks that can be directly applied to sky images.
The network is trained using simulated sky images corresponding to the T80-S Telescope optical model, a 80-cm survey imager at Cerro Tololo (Chile), which are synthesized using a Zernike polynomial representation of the optical system.
Once trained, the network can be used directly on sky images, outputting a corrected version of the image that has a constant and known PSF across its field of view. The method is to be tested on the T80-S Telescope.
We present the method and results on synthetic data.
Märkische Dialekte
(2021)
The efficiency of sediment routing from land to the ocean depends on the position of submarine canyon heads with regard to terrestrial sediment sources. We aim to identify the main controls on whether a submarine canyon head remains connected to terrestrial sediment input during Holocene sea-level rise. Globally, we identified 798 canyon heads that are currently located at the 120m-depth contour (the Last Glacial Maximum shoreline) and 183 canyon heads that are connected to the shore (within a distance of 6 km) during the present-day highstand. Regional hotspots of shore-connected canyons are the Mediterranean active margin and the Pacific coast of Central and South America. We used 34 terrestrial and marine predictor variables to predict shore-connected canyon occurrence using Bayesian regression. Our analysis shows that steep and narrow shelves facilitate canyon-head connectivity to the shore. Moreover, shore-connected canyons occur preferentially along active margins characterized by resistant bedrock and high river-water discharge.
Although teen dating violence (TDV) is internationally recognized as a serious threat to adolescents' health and well-being, almost no data is available for Slovenian youth. Hence, the purpose of this study was to examine the prevalence and predictors of TDV among Slovenian adolescents for the first time. Using data from the SPMAD study (Study of Parental Monitoring and Adolescent Delinquency), 330 high school students were asked about physical TDV victimization and perpetration as well as about their dating history, relationship conflicts, peers' antisocial behavior, and informal social control by family and school. A substantial number of female andmale adolescents reported victimization (16.7% of female and 12.7% of male respondents) and perpetration (21.1% of female and 6.0% of male respondents). Furthermore, the results revealed that lower age at the first relationship, relationship conflicts, and school informal social control were associated with victimization, whereas being female, relationship conflicts, having antisocial peers, and family informal social control were linked to perpetration. Implications of the study findings were discussed.
Energy system developments and investments in the decisive decade for the Paris Agreement goals
(2021)
The Paris Agreement does not only stipulate to limit the global average temperature increase to well below 2 °C, it also calls for 'making finance flows consistent with a pathway towards low greenhouse gas emissions'. Consequently, there is an urgent need to understand the implications of climate targets for energy systems and quantify the associated investment requirements in the coming decade. A meaningful analysis must however consider the near-term mitigation requirements to avoid the overshoot of a temperature goal. It must also include the recently observed fast technological progress in key mitigation options. Here, we use a new and unique scenario ensemble that limit peak warming by construction and that stems from seven up-to-date integrated assessment models. This allows us to study the near-term implications of different limits to peak temperature increase under a consistent and up-to-date set of assumptions. We find that ambitious immediate action allows for limiting median warming outcomes to well below 2 °C in all models. By contrast, current nationally determined contributions for 2030 would add around 0.2 °C of peak warming, leading to an unavoidable transgression of 1.5 °C in all models, and 2 °C in some. In contrast to the incremental changes as foreseen by current plans, ambitious peak warming targets require decisive emission cuts until 2030, with the most substantial contribution to decarbonization coming from the power sector. Therefore, investments into low-carbon power generation need to increase beyond current levels to meet the Paris goals, especially for solar and wind technologies and related system enhancements for electricity transmission, distribution and storage. Estimates on absolute investment levels, up-scaling of other low-carbon power generation technologies and investment shares in less ambitious scenarios vary considerably across models. In scenarios limiting peak warming to below 2 °C, while coal is phased out quickly, oil and gas are still being used significantly until 2030, albeit at lower than current levels. This requires continued investments into existing oil and gas infrastructure, but investments into new fields in such scenarios might not be needed. The results show that credible and effective policy action is essential for ensuring efficient allocation of investments aligned with medium-term climate targets.
This paper aims to analyse the figure of the Venus of Milo in (extreme) contemporary art productions. The reception of this sculpture has already been studied in the past, but without considering the last ten years (2010 – 2020), during which artists like Yinka Shonibare, Fabio Viale, or Daniel Arsham decided to use the Venus for their new productions. The paper also explains how the Venus of Milo became a globalised icon and an inspiration for artists from all over the world.
TransPipe
(2021)
Online learning environments, such as Massive Open Online Courses (MOOCs), often rely on videos as a major component to convey knowledge. However, these videos exclude potential participants who do not understand the lecturer’s language, regardless of whether that is due to language unfamiliarity or aural handicaps. Subtitles and/or interactive transcripts solve this issue, ease navigation based on the content, and enable indexing and retrieval by search engines. Although there are several automated speech-to-text converters and translation tools, their quality varies and the process of integrating them can be quite tedious. Thus, in practice, many videos on MOOC platforms only receive subtitles after the course is already finished (if at all) due to a lack of resources. This work describes an approach to tackle this issue by providing a dedicated tool, which is closing this gap between MOOC platforms and transcription and translation tools and offering a simple workflow that can easily be handled by users with a less technical background. The proposed method is designed and evaluated by qualitative interviews with three major MOOC providers.
§ 256 Nichtigkeit
(2021)
§§ 147-149
(2021)
Smend, Rudolf
(2021)