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A simple governor-based controller tuning is implemented and tested for the application to unmanned aerial vehicles (UAVs). We show that the governor-based tuning approach enables the high-level tuning of the existing controller of the UAVs by using a single tuning parameter only. We implement the approach on two UAV platforms of different sizes and controller frameworks to prove the versatility of the given approach. The validation is performed with experimental data collected for the UAVs flying in the supervised environment of an indoor flight laboratory.

We investigate a "learning to reject" framework to address the problem of silent failures in Domain Generalization (DG), where the test distribution differs from the training distribution. Assuming a mild distribution shift, we wish to accept out-of-distribution (OOD) data from a new domain whenever a model's estimated competence foresees trustworthy responses, instead of rejecting OOD data outright. Trustworthiness is then predicted via a proxy incompetence score that is tightly linked to the performance of a classifier. We present a comprehensive experimental evaluation of existing proxy scores as incompetence scores for classification and highlight the resulting trade-offs between rejection rate and accuracy gain. For comparability with prior work, we focus on standard DG benchmarks and consider the effect of measuring incompetence via different learned representations in a closed versus an open world setting. Our results suggest that increasing incompetence scores are indeed predictive of reduced accuracy, leading to significant improvements of the average accuracy below a suitable incompetence threshold. However, the scores are not yet good enough to allow for a favorable accuracy/rejection trade-off in all tested domains. Surprisingly, our results also indicate that classifiers optimized for DG robustness do not outperform a naive Empirical Risk Minimization (ERM) baseline in the competence region, that is, where test samples elicit low incompetence scores., The paper has been published at TMLR (see https://openreview.net/forum?id=TSy0vuwQFN)

Oceanography, 36 (1), ISSN:1042-8275, ISSN:2377-617X

We investigate single crystals of the trigonal antiferromagnet EuZn$_2$P$_2$ ($P\overline{3}m1$) by means of electrical transport, magnetization measurements, X-ray magnetic scattering, optical reflectivity, angle-resolved photoemission spectroscopy (ARPES) and ab-initio band structure calculations (DFT+U). We find that the electrical resistivity of EuZn$_2$P$_2$ increases strongly upon cooling and can be suppressed in magnetic fields by several orders of magnitude (CMR effect). Resonant magnetic scattering reveals a magnetic ordering vector of $q = (0\, 0\, \frac{1}{2})$, corresponding to an $A$-type antiferromagnetic (AFM) order, below $T_{\rm N} = 23.7\,\rm K$. We find that the moments are canted out of the $a-a$ plane by an angle of about $40^{\circ}\pm 10^{\circ}$ degrees and tilted away from the [100] - direction by $30^{\circ}\pm 5^{\circ}$. We observe nearly isotropic magnetization behavior for low fields and low temperatures which is consistent with the magnetic scattering results. The magnetization measurements show a deviation from the Curie-Weiss behavior below $\approx 150\,\rm K$, the temperature below which also the field dependence of the material's resistivity starts to increase. An analysis of the infrared reflectivity spectrum at $T=295\,\rm K$ allows us to resolve the main phonon bands and intra-/interband transitions, and estimate indirect and direct band gaps of $E_i^{\mathrm{opt}}=0.09\,\rm{eV}$ and $E_d^{\mathrm{opt}}=0.33\,\rm{eV}$, respectively, which are in good agreement with the theoretically predicted ones. The experimental band structure obtained by ARPES is nearly $T$-independent above and below $T_{\rm N}$. The comparison of the theoretical and experimental data shows a weak intermixing of the Eu 4$f$ states close to the $\Gamma$ point with the bands formed by the phosphorous 3$p$ orbitals leading to an induction of a small magnetic moment at the P sites.

The use of open-source software is crucial for the digitalization of manufacturing, including the implementation of Digital Twins as envisioned in Industry 4.0. This research paper provides a comprehensive comparison of free and open-source implementations of the reactive Asset Administration Shell (AAS) for creating Digital Twins. A structured search on GitHub and Google Scholar was conducted, leading to the selection of four implementations for detailed analysis. Objective evaluation criteria were defined, and a testing framework was created to test support for the most common AAS model elements and API calls. The results show that all implementations support at least a minimal set of required features while none implement the specification in all details, which highlights the challenges of implementing the AAS specification and the incompatibility between different implementations. This paper is therefore the first attempt at a comprehensive comparison of AAS implementations and identifies potential areas for improvement in future implementations. It also provides valuable insights for software developers and researchers in the field of AAS-based Digital Twins.

Combined resistance noise and muon-spin relaxation (μSR) measurements of the ferromagnetic semiconductor HgCr2Se4 suggest a degree of magnetoelectric coupling and provide evidence for the existence of isolated magnetic polarons. These form at elevated temperatures and undergo a percolation transition with a drastic enhancement of the low-frequency 1/ f -type charge fluctuations at the insulator-to-metal transition at ∼95–98 K in the vicinity of the magnetic ordering temperature TC ∼ 105–107 K. Upon approaching the percolation threshold from above, the strikingly unusual dynamics of a distinct two-level fluctuator superimposed on the 1/ f noise can be described by a slowing down of the dynamics of a nanoscale magnetic cluster, a magnetic polaron, when taking into account an effective radius of the polaron depending on the spin correlation length. Coinciding temperature scales found in μSR and noise measurements suggest changes in the magnetic dynamics over a wide range of frequencies and are consistent with the existence of large polarized and domain-wall-like regions at low temperatures, that result from the freezing of spin dynamics at the magnetic polaron percolation transition.

The low-temperature state of the quantum spin liquid candidate $κ$-(BEDT-TTF)$_{2}$Cu$_{2}$(CN)$_{3}$ emerges via an anomaly at $T^{*}\sim6$ K. Although signatures of this anomaly have been revealed in various quantities, its origin has remained unclear. Here we report inelastic neutron scattering measurements on single crystals of $κ$-(BEDT-TTF)$_{2}$Cu$_{2}$(CN)$_{3}$, aiming at studying phonon renormalization effects at $T^{*}$. A drastic change was observed in the phonon damping across $T^{*}$ for a breathing mode of BEDT-TTF dimers at $E=4.7$ meV. The abrupt change in the phonon damping is attributed to a phase transition into a valence bond solid state based on an effective model describing the spin-charge coupling in this dimer-Mott system., 5 pages, 3 figures, supplemental materials (8 pages, 6 figures)

While non-GAAP reporting is under debate as managers might opportunistically inflate non-GAAP earnings, analytical research by Hirshleifer and Teoh (2003) proposes that limited attention causes mispricing when inappropriate items are excluded from non-GAAP earnings but will be reversed subsequently. Addressing this proposition empirically, we find that market revisions upon the release of material restatements (a proxy of heightened investor attention) are more negative for firms that ex-ante excluded recurring expenses frequently (a proxy for inappropriate non-GAAP adjustments). This finding suggests that investors may fail to detect less salient, yet available, public information. Further, we document that investors reward aggressively reported non-GAAP earnings before the restatement announcement, but punish the same reporting choices in the post-restatement period. Overall, our findings suggest that investor attention, which increases after the restatement, enhances investors ability to disentangle aggressive from non-aggressive non-GAAP reporting choices. Findings hold for the pre- and post-Regulation G period. Oliver Mehring, Jens Müller, Sönke Sievers, Christian Sofilkanitsch

We investigate how managers smooth volatility in balance sheets, using the pension accounting change IAS 19R as a shock to balance sheet volatility. This shock increases pension plans’ funding transparency, which is the source of volatility, without targeting actual plan funding. We find that managers adjust funding levels, pension asset allocation and assumptions to mitigate volatility at this source, but also plan settlements increase drastically. The volatility of accruals decreases, whereas volatility of discretionary real decisions increases pointing to managerial decisions to alleviate volatility in balance sheets. The exposure to balance sheet volatility and the relative net costs of related smoothing are cross-sectional predictors of smoothing activities. Overall, we provide evidence consistent with a vast body of pension accounting literature mentioning but not explicitly investigating the transmission of pension plan volatility on firms’ balance sheets. Our findings link this literature with studies on balance sheet management and provide a new angle on the effects of a transparency mandate in (pension) accounting on managerial decision-making.

Gantry stages, which consist of two parallel acting servo drives, are commonly used in machine tools. One drawback of this concept is the crosstalk between both drives, when a stiff mechanical coupling is present. This can lead to a limited bandwidth of the position control or to high reaction forces. One way to overcome these issues is the usage of joints to create an additional degree of freedom, which allows the drives to move independently. The design of these joints as compliant elements offers advantages compared to common rolling bearings, such as low friction and the absence of backlash. Another benefit is the variability in the design of the compliant joints allowing for adjustments to the position of each joint’s centre of compliance. Thus, the position of the resulting pivot, and the transfer matrix between the motion of the drives and the motion at the gantry stage’s tool centre point, change as well. This paper addresses the placement of the joint’s centre of compliance in order to improve motion accuracy. For this purpose, joints with modular arranged compliant links have been designed. The characteristics of the joints and their effect on the behaviour of the gantry stage are compared using analytical investigations as well as experimental results.

While the public has noticed the need for the detection of potential tax loopholes and demands further improvement in the taxation of banks, there is scarce empirical evidence whether banks degree of tax avoidance actually differs from that of non-banks. We try to close this gap by investigating U.S. banks tax avoidance behavior for a sample period from 2004 to 2016. To identify banks tax avoidance, we use annual Cash ETRs and GAAP ETRs and compare them to the tax avoidance behavior of non-banks. As there are various channels of tax avoidance, we account for differences in several areas such as corporate fundamentals, the degree of multinationality and regulatory scrutiny. We provide cautious evidence that banks have significantly higher Cash ETRs than non-banks. Using quantile regression, we find evidence that the assocation between banks and ETRs is not constant over the whole tax avoidance distribution, with banks reporting significantly higher ETRs compared to nonbanks in those regions of the tax avoidance distribution which are regularly classified as “high tax avoidance”. In line with recent research, we provide some evidence that the difference in Cash ETRs between banks and non-banks is more pronounced for worse-capitalized, than for better-capitalized banks. Vanessa Gawehn, Jens Müller

In this experimental study, a passive flow control concept is provided to extend the stable part load operation regime by shifting the rise of the precessing vortex core (PVC), also known as vortex rope, toward lower mass flows respectively deeper part loads. A parametrized runner crown design working as a passive flow control device is derived. This control device aims for shifting the bifurcation point of the PVC to lower flow rates. To determine the most influential design parameters and derive an optimized runner crown design, a design of experiments (DoE) approach is used. This DoE approach is based on data obtained from differential pressure sensors inside the draft tube wall of a generic hydro turbine test rig using air as working fluid. By means of stochastic modeling, the growth rate of the PVC mode is derived from the statistics of the measured pressure signals. The growth rate is used to estimate the bifurcation point of the PVC characterized by a certain normalized flow rate. It is shown that the stable part load operation regime is extended by up to 25% due to the passive impact of the modified runner crown. Moreover, the operational range featuring considerable PVC-induced pressure oscillations is diminished and the pressure recovery of the draft tube is improved compared to the baseline case.

In view of the approaching application date of Regulation (EU) 2017/746 („IVDR“) and the resulting EU-wide, harmonized requirements for in-vitro diagnostic medical devices (IVD) manufactured and used within European health institutions, the Ad hoc Commission IVD of the German Association of the Scientific Medical Societies (AWMF) takes a national position on the details of the requirements and conditions related to the use of these IVD products. The Ad hoc Commission IVD emphasizes the relevance of examination procedures developed in medical laboratories, especially in the field of orphan diseases and new diagnostic markers. The IVDR sets an adequate regulatory framework for IVD manufactured and used within health institutions as long as these requirements are fulfilled with reliability and in accordance with the current state of the art in medical laboratory sciences. At the same time, the IVDR requirements have to be regarded under a pragmatic view and in accordance with the quality management systems approved within the different EU Member States. On the one hand, the mandatory requirements of the RiLiBÄK play an essential role in Germany. On the other hand, elements of voluntarily applicable international standards may support the fulfilment of product requirements for safety and performance according to Annex I of the IVDR. Both the complexity and possible solutions for the implementation of the IVDR requirements are discussed on the basis of examples such as the required documentation, performance evaluation and software validation. The Ad hoc Commission IVD recommends that, while aiming at a preferably EU-wide harmonized interpretation of the IVDR requirements, the flexibility in medical laboratory diagnostics necessary for patient care, including the use of IVD from in-house production, should be emphasized., Vor dem Hintergrund des nahenden Geltungsbeginns der Verordnung (EU) 2017/746 („IVDR“) und der damit EU-weit harmonisierten Anforderungen an In-vitro-Diagnostika (IVD) aus Eigenherstellung positioniert sich die Ad-hoc-Kommission In-vitro-Diagnostika der Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF) im Einzelnen zu den in der IVDR gestellten Anforderungen und Bedingungen zur Verwendung dieser Produkte. Die Ad-hoc-Kommission IVD hebt die Bedeutung von in medizinischen Laboratorien eigenentwickelten Untersuchungsverfahren für die Patientenversorgung vor allem im Bereich seltener Erkrankungen und neuer diagnostischer Marker hervor. Die IVDR bildet für die Entwicklung und Verwendung von IVD aus Eigenherstellung einen passenden regulatorischen Rahmen, sofern die Anforderungen zuverlässig entsprechend dem Stand der medizinischen Wissenschaft und Technik, aber zugleich pragmatisch und in Übereinstimmung mit den in den Mitgliedstaaten bewährten Qualitätsmanagementsystemen umgesetzt werden. In Deutschland sind hier einerseits die verpflichtenden Anforderungen der RiLiBÄK zu nennen. Andererseits können Elemente von freiwillig anzuwendenden internationalen Normen dazu dienen, die nach Anhang I der IVDR umzusetzenden Anforderungen an Sicherheit und Leistung für IVD aus Eigenherstellung zu erfüllen. Sowohl die Komplexität als auch Lösungskonzepte zur Umsetzung der Anforderungen werden u.a. am Beispiel der erforderlichen Dokumentation, der Leistungsbewertung und der ggf. durchzuführenden Softwarevalidierung aufgezeigt. Die Ad-hoc-Kommission empfiehlt, bei einer möglichst weitreichend harmonisierten Interpretation der Anforderungen gleichzeitig die für die Patientenversorgung notwendige Flexibilität in der labordiagnostischen Versorgung einschließlich der Verwendung von IVD aus Eigenherstellung zu gewährleisten., GMS German Medical Science; 19:Doc08

In view of the approaching application date of Regulation (EU) 2017/746 („IVDR“) and the resulting EU-wide, harmonized requirements for in vitro diagnostic medical devices (IVD) manufactured and used within European health institutions, the Ad hoc Commission IVD“ of the German Association of the Scientific Medical Societies (AWMF) takes a national position on the details of the requirements and conditions related to the use of these IVD products. The Ad hoc Commission IVD emphasizes the relevance of examination procedures developed in medical laboratories, especially in the field of orphan diseases and new diagnostic markers. The IVDR sets an adequate regulatory framework for IVD manufactured and used within health institutions as long as these requirements are fulfilled with reliability and in accordance with the current state of the art in medical laboratory sciences. At the same time, the IVDR requirements have to be regarded under a pragmatic view and in accordance with the quality management systems approved within the diffferent EU Member States. On the one hand, the mandatory requirements of the RiLiBÄK play an essential role in Germany. On the other hand, elements of voluntarily applicable international standards may support the fulfilment of product requirements for safety and performance according to Annex I of the IVDR. Both the complexity and possible solutions for the implementation of the IVDR requirements are discussed on the basis of examples such as the required documentation, performance evaluation and software validation. The Ad hoc Commission IVD recommends that, while aiming at a preferably EU-wide harmonized interpretation of the IVDR requirements, the flexibility in medical laboratory diagnostics necessary for patient care, including the use of IVDs from in-house production, should be emphasized., Vor dem Hintergrund des nahenden Geltungsbeginns der Verordnung (EU) 2017/746 („IVDR“) und der damit EU-weit harmonisierten Anforderungen an In-vitro-Diagnostika (IVD) aus Eigenherstellung positioniert sich die Ad-hoc-Kommission In-vitro-Diagnostika der Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF) im Einzelnen zu den in der IVDR gestellten Anforderungen und Bedingungen zur Verwendung dieser Produkte. Die Ad-hoc-Kommission IVD hebt die Bedeutung von in medizinischen Laboratorien eigenentwickelten Untersuchungsverfahren für die Patientenversorgung vor allem im Bereich seltener Erkrankungen und neuer diagnostischer Marker hervor. Die IVDR bildet für die Entwicklung und Verwendung von IVD aus Eigenherstellung einen passenden regulatorischen Rahmen, sofern die Anforderungen zuverlässig entsprechend dem Stand der medizinischen Wissenschaft und Technik, aber zugleich pragmatisch und in Übereinstimmung mit den in den Mitgliedstaaten bewährten Qualitätsmanagementsystemen umgesetzt werden. In Deutschland sind hier einerseits die verpflichtenden Anforderungen der RiLiBÄK zu nennen. Andererseits können Elemente von freiwillig anzuwendenden internationalen Normen dazu dienen, die nach Anhang I der IVDR umzusetzenden Anforderungen an Sicherheit und Leistung für IVD aus Eigenherstellung zu erfüllen. Sowohl die Komplexität als auch Lösungskonzepte zur Umsetzung der Anforderungen werden u.a. am Beispiel der erforderlichen Dokumentation, der Leistungsbewertung und der ggf. durchzuführenden Softwarevalidierung aufgezeigt. Die Ad-hoc-Kommission empfiehlt, bei einer möglichst weitreichend harmonisierten Interpretation der Anforderungen gleichzeitig die für die Patientenversorgung notwendige Flexibilität in der labordiagnostischen Versorgung einschließlich der Verwendung von IVD aus Eigenherstellung zu gewährleisten., GMS Zeitschrift zur Förderung der Qualitätssicherung in medizinischen Laboratorien; 12:Doc03

Organic matter production by cyanobacteria blooms is a major environmental concern for the Baltic Sea as it promotes thespread of anoxic zones. Partial pressure of carbon dioxide (pCO2) measurements carried out on Ships of Opportunity (SOOP) since 2003 have proven to be a powerful tool to resolve the carbon dynamics of the blooms in space and time. However, SOOP measurements lack the possibility to directly constrain the depth–integrated net community production (NCP) due to their restriction to the sea surface. This study tackles the resulting knowledge gap through (1) providing a best–guess NCP estimatefor an individual cyanobacteria bloom based on repeated profiling measurements of pCO2 and (2) establishing an algorithm to accurately reconstruct depth–integrated NCP from surface pCO2 observations in combination with modelled temperature profiles. Goal (1) was achieved by deploying state–of–the–art sensor technology from a small–scale sailing vessel. The low–cost and flexible platform enabled observations covering an entire bloom event that occurred in July and August 2018 in the Eastern Gotland Sea. For the biogeochemical interpretation, recorded pCO2 profiles were converted to CT*, which is the dissolved inorganic carbon concentration normalised to alkalinity. We found that the investigated Nodularia–dominated bloom event had many biogeochemical characteristics in common with blooms in previous years. In particular, it lasted for about three weeks, caused a CT* drawdown of 80 μmol kg−1, and was accompanied by a sea surface temperature increase of 10 °C. The novel finding of this study is the vertical extension of the CT* drawdown up to 12 m water depth. Integration of the CT* drawdown across this depth and correction for vertical fluxes permit a best–guess NCP estimate of ~1.2 mol–C m−2. Addressing goal (2), we combined modelled hydrographical profiles with surface pCO2 observations recorded by SOOP Finnmaid within the study area. Introducing the temperature penetration depth (TPD) as a new parameter to integrate SOOP observations across depth, we achieve a reconstructed NCP estimate that agrees to the best–guess within 10 %. Applying the TPD approach to almost two decades of surface pCO2 observations available for the Baltic Sea bears the potential to provide new insights into the control and long–term trends of cyanobacteria NCP. This understanding is key for an effective design and monitoring of conservation measures aiming at a Good Environmental Status of the Baltic Sea.

The concept of digital twins (DT) has already been discussed some decades ago. Digital representations of physical assets are key components in industrial applications as they are the basis for decision making. What is new is the conceptual approach to consider DT as well-defined software entities themselves that follow the whole lifecycle of their physical counterparts from the engineering, operation up to the discharge, and hence, have their own type description, identity, and lifecycle. This paper elaborates on this idea and argues the need for systematic DT engineering and management. After a conceptual description of DT, the paper proposes a DT lifecycle model and presents methodologies and tools for DT management, also in the context of Industrie 4.0 concepts, such as the asset administration shell (AAS), the international data spaces (IDS), and IEC standards (such as OPC UA and AML). As a tool example for the support of DT engineering and management, the Fraunhofer-advanced AAS tools for digital twins (FA3ST) are presented in more detail.

The direction and magnitude of carbon dioxide fluxes between the atmosphere and the sea are regulated by the gradient in the partial pressure of carbon dioxide (pCO2) across the air–sea interface. Typically, observations of pCO2 at the sea surface are carried out by using research vessels and ships of opportunity, which usually do not resolve the diurnal cycle of pCO2 at a given location. This study evaluates the magnitude and driving processes of the diurnal cycle of pCO2 in a coastal region of the Baltic Sea. We present pCO2 data from July 2018 to June 2019 measured in the vicinity of the island of Utö at the outer edge of the Archipelago Sea, and quantify the relevant physical, biological, and chemical processes controlling pCO2. The highest monthly median of diurnal pCO2 variability (31 µatm) was observed in August and predominantly driven by biological processes. Biological fixation and mineralization of carbon led to sinusoidal diurnal pCO2 variations, with a maximum in the morning and a minimum in the afternoon. Compared with the biological carbon transformations, the impacts of air–sea fluxes and temperature changes on pCO2 were small, with their contributions to the monthly medians of diurnal pCO2 variability being up to 12 and 5 µatm, respectively. During upwelling events, short-term pCO2 variability (up to 500 µatm within a day) largely exceeded the usual diurnal cycle. If the net annual air–sea flux of carbon dioxide at our study site and for the sampled period is calculated based on a data subset that consists of only one regular measurement per day, the bias in the net exchange depends on the sampling time and can amount up to ±12 %. This finding highlights the importance of continuous surface pCO2 measurements at fixed locations for the assessment of the short-term variability of the carbonate system and the correct determination of air–sea CO2 fluxes., Ocean Science, 17 (6), ISSN:1812-0784, ISSN:1812-0792

In den 1980er-Jahren etablierte sich der Begriff des digitalen oder elektronischen Büros, um die radikale Veränderung unserer Arbeitswelt vom analogen hin zum digitalen Zeitalter zu beschreiben. Obwohl das digitale Büro heutzutage in den meisten Unternehmen, Organisationen und Behörden Realität ist, basiert es noch immer auf von Altlasten behafteten Protokollen und Datenformaten. Diese Arbeit stellt eine umfassende Analyse der IT-Sicherheits-Bausteine des digitalen Büros dar. Der Fokus liegt dabei auf den Bereichen E-Mail-Sicherheit, Dokumentensicherheit und Druckersicherheit. Es werden signifikante Designfehler in den angewandten Technologien demonstriert, welche auf die frühen 1980er (PostScript), 1990er (PJL, PDF, PGP, S/MIME) und die 2000er-Jahre (ODF, OOXML) zurückgehen. Dabei sind diese Technologien keineswegs überholt, sondern gelten mittlerweile als etabliert, unverzichtbar und allgegenwärtig.

The direction and magnitude of carbon dioxide exchange between the atmosphere and the sea is regulated by their difference in partial pressure of carbon dioxide (pCO2). Typically, observations of pCO2 are carried out by using research vessels and voluntary observing ships which cannot easily detect the diurnal cycle of pCO2 at a given location. This study evaluates the magnitude and driving processes of the diurnal cycle of pCO2 in a coastal region of the Baltic Sea during the different seasons.We present pCO2 data from July 2018–June 2019 carried out in the vicinity of the island of Utö in the Archipelago Sea and quantify the relevant physical, biological and chemical processes affecting pCO2. The highest monthly median diurnal pCO2 peak-to-peak amplitude (31 μatm) was observed in August. This high diurnal variation was found to be related predominantly to biological processes. The biological transformations of carbon generated a sinusoidal diurnal pCO2 variation, with a maximum in the morning and a minimum in the afternoon. Compared to the biological carbon transformations, the effect of air sea exchange of carbon dioxide and the effect of temperature changes on pCO2 are smaller, with their monthly median peak-to-peak amplitudes were up to 12 and 5 μatm, respectively. Single diurnal peak-to-peak amplitudes can be significantly larger (up to 500 μatm), during upwelling. If the net exchange of carbon dioxide between the sea and atmosphere on our study site and sampling period is calculated based on a data set that consists of only one measurement per day, the error in the budget depends on the sampling time and can be up to ±12 %.

Dataset from Uto Atmospheric and Marine Research Station (59°46’55” N, 21°21’27” E) between July 2018 and June 2019 This is a dataset for the publication: Martti Honkanen, Jens Daniel Müller, Jukka Seppälä, Gregor Rehder, Sami Kielosto, Pasi Ylöstalo, Timo Mäkelä, Juha Hatakka, and Lauri Laakso: Diurnal cycle of the CO2 system in the coastal region of the Baltic Sea (Submitted to Ocean Science 2020/11). The dataset consists of 1 hour average values of the variables used in the paper. The data are in a comma separated file that has blanks as the nan values.

Background: Establishing a methodology for assessing nutritional behavior comprehensively and accurately poses a great challenge. Mobile technologies such as mobile image-based food recording apps enable eating events to be assessed in the moment in real time, thereby reducing memory biases inherent in retrospective food records. However, users might find it challenging to take images of the food they consume at every eating event over an extended period, which might lead to incomplete records of eating events (missing events).Objective: Analyzing data from 3 studies that used mobile image-based food recording apps and varied in their technical enrichment, this study aims to assess how often eating events (meals and snacks) were missed over a period of 8 days in a naturalistic setting by comparing the number of recorded events with the number of normative expected events, over time, and with recollections of missing events.Methods: Participants in 3 event-based Ecological Momentary Assessment (EMA) studies using mobile image-based dietary assessments were asked to record all eating events (study 1, N=38, 1070 eating events; study 2, N=35, 934 eating events; study 3, N=110, 3469 eating events). Study 1 used a basic app; study 2 included 1 fixed reminder and the possibility to add meals after the actual eating events occurred instead of in the moment (addendum); and study 3 included 2 fixed reminders, an addendum feature, and the option to record skipped meals. The number of recalled missed events and their reasons were assessed by semistructured interviews after the EMA period (studies 1 and 2) and daily questionnaires (study 3).Results: Overall, 183 participants reported 5473 eating events. Although the momentary adherence rate as indexed by a comparison with normative expected events was generally high across all 3 studies, a differential pattern of results emerged with a higher rate of logged meals in the more technically intensive study 3. Multilevel models for the logging trajectories of reported meals in all 3 studies showed a significant, albeit small, decline over time (b=−.11 to −.14, PsConclusions: Three different indicators (normative, time stability, and recalled missing events) consistently indicated missing events. However, given the intensive nature of diet EMA protocols, the effect sizes were rather small and the logging trajectories over time were remarkably stable. Moreover, the individual’s actual state and context seemed to exert a greater influence on adherence rates than stable individual differences, which emphasizes the need for a more nuanced understanding of the factors that affect momentary adherence. published

This study examines strategic alliances as channels for tax knowledge diffusion between firms. Although strategic alliances are primarily expected to foster their main business purposes, we focus on whether tax knowledge potentially diffuses as a second order effect of peer-to-peer cooperation. To tease out diffusion of tax knowledge, we investigate changes in the tax planning behavior of high-tax firms in strategic alliances with low-tax firms in comparison to high-tax firms in strategic alliances with other high-tax firms. Our results suggest an economically meaningful decrease of high-tax firms' cash effective tax rates when cooperating with low-tax firms. Additionally, we find that this adjustment occurs within two years of a strategic alliance's initiation. We apply textual analysis to control for the strategic alliances' main business purposes in our analyses. Because these activities do not appear to drive our findings, we argue to identify tax knowledge diffusion as a second order effect and conjecture that strategic alliances are not intended to be tax planning investments. Finally, we test whether partner characteristics intensify or mitigate the identified effects. Overall, our results provide robust evidence for tax knowledge diffusion via strategic alliances.

OpenPGP and S/MIME are the two major standards to encrypt and digitally sign emails. Digital signatures are supposed to guarantee authenticity and integrity of messages. In this work we show practical forgery attacks against various implementations of OpenPGP and S/MIME email signature verification in five attack classes: (1) We analyze edge cases in S/MIME's container format. (2) We exploit in-band signaling in the GnuPG API, the most widely used OpenPGP implementation. (3) We apply MIME wrapping attacks that abuse the email clients' handling of partially signed messages. (4) We analyze weaknesses in the binding of signed messages to the sender identity. (5) We systematically test email clients for UI redressing attacks. Our attacks allow the spoofing of digital signatures for arbitrary messages in 14 out of 20 tested OpenPGP-capable email clients and 15 out of 22 email clients supporting S/MIME signatures. While the attacks do not target the underlying cryptographic primitives of digital signatures, they raise concerns about the actual security of OpenPGP and S/MIME email applications. Finally, we propose mitigation strategies to counter these attacks. Topics

Inelastic neutron scattering measurements on the molecular dimer-Mott insulator $\kappa$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Cl reveal a phonon anomaly in a wide temperature range. Starting from $T_{\rm ins}\sim50$-$60$ K where the charge gap opens, the low-lying optical phonon modes become overdamped upon cooling towards the antiferromagnetic ordering temperature $T_\mathrm{N} = 27$ K, where also a ferroelectric ordering at $T_{\rm FE} \approx T_{\rm N}$ occurs. Conversely, the phonon damping becomes small again when spins and charges are ordered below $T_\mathrm{N}$, while no change of the lattice symmetry is observed across $T_\mathrm{N}$ in neutron diffraction measurements. We assign the phonon anomalies to structural fluctuations coupled to charge and spin degrees of freedom in the BEDT-TTF molecules., Comment: 6 pages, 3 figures with Erratum ( 4 pages, 2 figures) and supplemental material (4 pages, 4 figures)

We examine the disclosure of GAAP effective tax rate (ETR) information in firms financial statements. Applying the theoretical underpinnings of Wagenhofer (1990) to a tax setting, we argue that firms face a tradeoff in their GAAP ETR disclosure decision. On the one hand, firms have incentives to increase GAAP ETR disclosure if the ratio has a condition that is favorable from an investors perspective, expecting positive capital market reactions. On the other hand, the disclosure might draw tax auditors and public attention to the GAAP ETR and result in proprietary costs in terms of additional tax payments or reputational damages. We empirically test the disclosure behavior by examining the relation between disclosure intensity and five different measures of favorable GAAP ETR conditions. First, we provide evidence that the annual report section in which most of the firms disclose GAAP ETR information is the management report, indicating that firms assign considerable relevance to the ratio. Second, we find a higher disclosure intensity if the GAAP ETR has a favorable condition, i.e. is decreasing or near the average ratio of firms in the same industry or size group. We do not find a significant relation to the disclosure level for smooth GAAP ETRs. Our findings indicate that firms assess the benefits of providing the favorable GAAP ETR information to be higher than the related costs. Documenting firms GAAP ETR reporting behavior, we contribute to the tax disclosure literature by providing insights into possible disclosure incentives. Further, our results could increase awareness among investors to have a second look at the GAAP ETR if the disclosure intensity with respect to the ratio is low. Vanessa Flagmeier, Jens Müller, Caren Sureth-Sloane

We show practical attacks against OpenPGP and S/MIME encryption and digital signatures in the context of email. Instead of targeting the underlying cryptographic primitives, our attacks abuse legitimate features of the MIME standard and HTML, as supported by email clients, to deceive the user regarding the actual message content. We demonstrate how the attacker can unknowingly abuse the user as a decryption oracle by replying to an unsuspicious looking email. Using this technique, the plaintext of hundreds of encrypted emails can be leaked at once. Furthermore, we show how users could be tricked into signing arbitrary text by replying to emails containing CSS conditional rules. An evaluation shows that 17 out of 19 OpenPGP-capable email clients, as well as 21 out of 22 clients supporting S/MIME, are vulnerable to at least one attack. We provide different countermeasures and discuss their advantages and disadvantages.

While the public has noticed the need for the detection of potential tax loopholes and demand further improvement in the taxation of banks, there is scarce empirical evidence of whether banks' degree of tax avoidance actually differs from that of non-banks. We try to close this gap by investigating U.S. banks' tax avoidance behavior for a sample period from 2004 to 2016. To anchor banks' tax avoidance, we use annual Cash ETRs and GAAP ETRs and compare them to the tax avoidance behavior of non-banks. As there are various channels of tax avoidance, we account for differences in several areas such as corporate fundamentals, the degree of multinationality and regulatory scrutiny. We provide cautious evidence that banks have significantly larger Cash ETRs than non-banks. Via the use of quantile regression we find evidence that the assocation between banks and ETRs is not constant over the whole tax avoidance distribution, but shows a positive association for lower parts of the tax avoidance distribution and a negative association for higher parts. In line with recent research, we provide some evidence that the difference in Cash ETRs between banks and non-banks is more pronounced for worse-capitalized, than for better-capitalized banks.

The IBM Db2 Analytics Accelerator (IDAA) is a state-of-the art hybrid database system that seamlessly extends the strong transactional capabilities of Db2 for z/OS (Db2z) with very fast column-store processing in Db2 Database for Linux, Unix, and Windows. IDAA maintains a copy of the data from Db2z in its backend database. The data can be synchronized in batch with a granularity of table partitions, or incrementally using replication technology for individual rows. In this paper we present the enablement of combining the batch loading of a true subset of a table’s partitions for replicated tables. The primary goal for such an integration is to ensure data consistency. A specific challenge is that no duplicated rows stemming from the two data transfer paths come into existence. We present a robust and yet simple approach that is based on IDAA’s implementation of multi-version concurrency control.

We examine whether companies voluntarily disclose additional information about tax losscarryforwards when the recoverability is more uncertain. With this study, we aim to explain part of thehuge cross-sectional variation in the tax footnote. To assess disclosure behavior, we hand-collect datafrom notes of large German firms IFRS financial statements and identify voluntarily disclosedinformation. First, our results support prior literatures evidence of a considerable cross-sectionalvariation of disclosure in the tax footnote. Second, we find that uncertainty about the usability of taxlosses has a significantly positive relation to the amount and quality of disclosure, controlling for otherdisclosure determinants derived from prior literature and for sample selection. Third, our results indicatethat the observed disclosure behavior is not simply a reflection of the firms general disclosure behaviorbut specific to the tax footnote. These findings are robust to several historic and forward-lookingindicators representing uncertainty. Our findings suggest that managers anticipate the investors needfor more private information and disclose them voluntarily to reduce information asymmetries. Thisresult indicates that part of the cross-sectional variation in the tax footnote can be explained by firmsanticipating investors demand for additional information. Vanessa Flagmeier, Jens Müller

Inorganic phosphate (Pi) is often a limiting plant nutrient. In members of the Brassicaceae family, such as Arabidopsis (Arabidopsis thaliana), Pi deprivation reshapes root system architecture to favor topsoil foraging. It does so by inhibiting primary root extension and stimulating lateral root formation. Root growth inhibition from phosphate (Pi) deficiency is triggered by iron-stimulated, apoplastic reactive oxygen species generation and cell wall modifications, which impair cell-to-cell communication and meristem maintenance. These processes require LOW PHOSPHATE RESPONSE1 (LPR1), a cell wall-targeted ferroxidase, and PHOSPHATE DEFICIENCY RESPONSE2 (PDR2), the single endoplasmic reticulum (ER)-resident P5-type ATPase (AtP5A), which is thought to control LPR1 secretion or activity. Autophagy is a conserved process involving the vacuolar degradation of cellular components. While the function of autophagy is well established under nutrient starvation (C, N, or S), it remains to be explored under Pi deprivation. Because AtP5A/PDR2 likely functions in the ER stress response, we analyzed the effect of Pi limitation on autophagy. Our comparative study of mutants defective in the local Pi deficiency response, ER stress response, and autophagy demonstrated that ER stress-dependent autophagy is rapidly activated as part of the developmental root response to Pi limitation and requires the genetic PDR2-LPR1 module. We conclude that Pi-dependent activation of autophagy in the root apex is a consequence of local Pi sensing and the associated ER stress response, rather than a means for systemic recycling of the macronutrient.

Einleitung: Die Medizinische Hochschule Hannover (MHH) gehört zu den forschungsstärksten Hochschuleinrichtungen [ref:1] und ist Spitzenreiter hinsichtlich der Publikationsintensität in der Universitätsmedizin in Deutschland [ref:2]. In diesem kompetitiven Umfeld[zum vollständigen Text gelangen Sie über die oben angegebene URL], 63. Jahrestagung der Deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie e.V. (GMDS)

Herein, we present a small and versatile optode system with integrated battery and logger for monitoring of O-2, pH, and pCO(2) in seawater. Three sensing materials designed for seawater measurements are optimized with respect to dynamic measurement range and long-term stability. The spectral properties of the sensing materials were tailored to be compatible with a commercially available laboratory oxygen logger that was fitted into a pressure housing. Interchangeable sensor caps with appropriate "sensing chemistry" are conveniently attached to the end of the optical fiber. This approach allows using the same instrument for multiple analytes, which offers great flexibility and minimizes hardware costs. Applications of the new optode system were demonstrated by recording depth profiles for the three parameters during a research cruise in the Baltic Sea and by measuring surface water transects of pH. The optode was furthermore used to monitor the concentration of dissolved oxygen in a seagrass meadow in the Limfjord, Denmark, and sensor packages consisting of pO(2), pH, and pCO(2) were deployed in the harbors of Kiel, Germany, and Southampton, England, for 6 d. The measurements revealed that the system can resolve typical patterns in seawater chemistry related to spatial heterogeneities as well as temporal changes caused by biological and tidal activity.

Fluctuation spectroscopy measurements of quasi-two-dimensional organic charge-transfer salts (BEDT-TTF) 2 X are reviewed. In the past decade, the method has served as a new approach for studying the low-frequency dynamics of strongly correlated charge carriers in these materials. We review some basic aspects of electronic fluctuations in solids, and give an overview of selected problems where the analysis of 1 / f -type fluctuations and the corresponding slow dynamics provide a better understanding of the underlying physics. These examples are related to (1) an inhomogeneous current distribution due to phase separation and/or a percolative transition; (2) slow dynamics due to a glassy freezing either of structural degrees of freedom coupling to the electronic properties or (3) of the electrons themselves, e.g., when residing on a highly-frustrated crystal lattice, where slow and heterogeneous dynamics are key experimental properties for the vitrification process of a supercooled charge-liquid. Another example is (4), the near divergence and critical slowing down of charge carrier fluctuations at the finite-temperature critical endpoint of the Mott metal-insulator transition. Here also indications for a glassy freezing and temporal and spatial correlated dynamics are found. Mapping out the region of ergodicity breaking and understanding the influence of disorder on the temporal and spatial correlated fluctuations will be an important realm of future studies, as well as the fluctuation properties deep in the Mott or charge-ordered insulating states providing a connection to relaxor or ordered ferroelectric states studied by dielectric spectroscopy.

Globally, ocean acidification presents a threat to marine ecosystems. In the Baltic Sea, this process could so far not be quantified, partly due to a lack of appropriate pH observations. This study unravels a positive alkalinity trend in the Baltic Sea over the past two decades that counteracted acidification. Further, state-of-the-art spectrophotometric pH measurements in brackish waters are enabled by characterizing pH buffer solutions and the indicator dye m-Cresol purple at low salinities. Finally, pH fluctuations and their implications for benthic ecosystems are examined.

Augmented Reality (AR) can create the illusion of virtual objects being integrated into the viewer’s physical environment. Researchers have identified numerous application areas that can benefit from AR. Moreover, they have suggested AR displays as tools to support co-located and distributed collaboration. Usually, collaboration requires the collaborators to coordinate their joint actions through conversation. Today, an increasing number of AR-capable smartphones and tablets contributes to the dissemination of AR technology. Yet, research has not widely investigated the question of how ARs can be designed to support conversation and collaboration. With the goal of informing interaction designers, this thesis studies how the design of ARs can facilitate collaborative, spatial activities. It builds on the assumption that spatial activities require the collaborators to exchange spatial information through conversation, e. g., to guide each other’s attention to a task object in the AR environment. To specify the location of a specific task object, speakers often utilize visually outstanding objects—so-called landmarks—as reference objects. Collaborative ARs, however, do not necessarily provide as many landmarks as some spatial activities would require. Moreover, distributed ARs may only offer physical landmarks that exist in one of the collaborator’s environment exclusively. Such landmarks are, therefore, useless for spatial conversations with a remote AR-collaborator. This work makes two propositions to overcome this issue of missing referencing options during co-located and distributed, collaborative spatial activities. The first proposition consists in adding shared, virtual landmarks to the collaborators’ AR. The second proposition consists in embedding both the task objects and the virtual landmarks into a shared, virtual environment. Within three controlled lab studies, this thesis evaluates the two propositions and makes three contributions. First, it provides a better understanding of how the propositions shape synchronous, co-located, and distributed spatial referencing. Second, it provides a set of design guidelines on how to support collaborative activities in AR that involve spatial referencing. Third, it informs future research to support AR-based, collaborative spatial activities. published

By the fabrication of periodically arranged nanomagnetic systems it is possible to engineer novel physical properties by realizing artificial lattice geometries that are not accessible via natural crystallization or chemical synthesis. This has been accomplished with great success in two dimensions in the fields of artificial spin ice and magnetic logic devices, to name just two. Although first proposals have been made to advance into three dimensions (3D), established nanofabrication pathways based on electron beam lithography have not been adapted to obtain free-form 3D nanostructures. Here we demonstrate the direct-write fabrication of freestanding ferromagnetic 3D nano-architectures. By employing micro-Hall sensing, we have determined the magnetic stray field generated by our free-form structures in an externally applied magnetic field and we have performed micromagnetic and macro-spin simulations to deduce the spatial magnetization profiles in the structures and analyze their switching behavior. Furthermore we show that the magnetic 3D elements can be combined with other 3D elements of different chemical composition and intrinsic material properties. Funding Agencies|Deutsche Forschungsgemeinschaft (DFG) [SFB/TR 49]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Faculty of Materials Engineering, University of Babylon, Babylon, Iraq; Deutscher Akademischer Austauschdienst (DAAD); COST Action [CM1301]

We present high-resolution measurements of the relative length change as a function of temperature of the organic charge-transfer salt $\kappa$-(BEDT-TTF)$_2$Hg(SCN)$_2$Cl. We identify anomalous features at $T_g \approx\,63$ K which can be assigned to a kinetic glass-like ordering transition. By determining the activation energy $E_A$, this glass-like transition can be related to conformational degrees of freedom of the ethylene endgroups of the organic building block BEDT-TTF. As opposed to other $\kappa$-(BEDT-TTF)$_2X$ salts, we identify a peculiar ethylene endgroup ordering in the present material in which only one of the two crystallographically inequivalent ethylene endgroups is subject to glass-like ordering. This experimental finding is fully consistent with our predictions from $ab\,initio$ calculations from which we estimate the energy differences $\Delta E$ and the activation energies $E_A$ between different conformations. The present results indicate that the specific interaction between the ethylene endgroups and the nearby anion layers leads to different energetics of the inequivalent ethylene endgroups, as evidenced by different ratios $E_A/\Delta E$. We infer that the ratio $E_A/\Delta E$ is a suitable parameter to identify the tendency of ethylene endgroups towards glass-like freezing., Comment: 10 pages, 6 figures, Supplementary Information (2 pages)

Numerous studies have been conducted on the effect of ocean acidification on calcifiers inhabiting nearshore benthic habitats, such as the blue mussel Mytilus edulis. The majority of these experiments was performed under stable CO2 partial pressure (pCO2), carbonate chemistry and oxygen (O2) levels, reflecting present or expected future open ocean conditions. Consequently, levels and variations occurring in coastal habitats, due to biotic and abiotic processes, were mostly neglected, even though these variations largely override global long-term trends. To highlight this hiatus and guide future research, state-of-the-art technologies were deployed to obtain high-resolution time series of pCO2 and [O2] on a mussel patch within a Zostera marina seagrass bed, in Kiel Bay (western Baltic Sea) in August and September 2013. Combining the in situ data with results of discrete sample measurements, a full seawater carbonate chemistry was derived using statistical models. An average pCO2 more than 50 % (~ 640 µatm) higher than current atmospheric levels was found right above the mussel patch. Diel amplitudes of pCO2 were large: 765 ± 310 (mean ± SD). Corrosive conditions for calcium carbonates (Ωarag and Ωcalc&thinsp

The method of loci is a technique to memorize large quantities of information by associating the items to be learned with familiar places (loci). The effectiveness of the technique has been well established, but the initial creation of the loci can be a tedious task. With the aim of supporting flexible learning in situ, we introduce Loci Spheres, a novel concept which facilitates the creation of loci using mobile devices. We present three variants which support the technique to varying degrees: spatial loci (uses spatial input) and panning loci (uses panning) to define and navigate the loci, and no loci (baseline condition), where users have to create the loci within their imagination. In an in-the-wild study we investigated perceived system support, usage behavior, and effectiveness of the three variants. With this work we introduce a novel memorization tool which addresses the potential barrier involved in loci creation and provide a set of four design principles on how to leverage the technique with mobile devices in everyday situations. published

A framework for obtaining adjoint gradients for coupled conjugate heat transfer problems is presented. The framework is tailored to partitioned approaches in which separate solvers are used for the fluid and solid domains. The exchange of sensitiv- ities between adjoint fluid and solid solvers is necessary in order to obtain gradients and how this is achieved is described. The effectiveness of the procedure is demonstrated by solving a conjugate heat transfer problem using a gradient based approach. The presented method can be extended to sensitivity analysis of multidisciplinary problems where both solvers offer adjoint derivatives.

Building nanotechnological analogues of naturally occurring magnetic structures has proven to be a powerful approach to studying topics like geometry-induced magnetic frustration and to provide model systems for statistical physics. Moreover, it practically allows to engineer novel physical properties by realizing artificial lattice geometries that are not accessible via natural crystallization or chemical synthesis. This has been accomplished with great success in the field of two-dimensional artificial spin ice systems with important branches reaching into the field of magnetic logic devices. Although first proposals have been made to advance into three dimensions (3D), established nanofabrication pathways based on electron beam lithography have not been adapted to obtain free-form 3D nanostructures. Here we demonstrate the direct-write fabrication of freestanding ferromagnetic 3D nano-architectures with full control over the degree of magnetic frustration. By employing micro-Hall sensing, we have determined the magnetic stray field generated by our free-form structures in an externally applied magnetic field and we have performed micromagnetic and macro-spin simulations to deduce the spatial magnetization profiles in the structures and analyze their switching behavior. Furthermore we show that the magnetic 3D elements can be combined with other 3D elements of different chemical composition and intrinsic material properties.

The implementation of the german energy transition (Energiewende) is unclear in its configuration and timeframe. The future of the transition depends on more than factors such as technological development, economic feasibility and political framing. Rather, maintaining a positive attitude by society and its understanding is significant. Therefore, effectively communicating the complex process of energy transition is essenial. For preserving the variety of aspects and the multitude of perspectives in this open process we choose the format of a seriousgame. We explain why we think developing seriousgames can be an appropriate tool for that purpose. Contrary to existing games on that topic, we focused on motives, attitudes and the implications in a world full of contradictions and caprices in everydaylife. We created an innovative Adventure, which focusses on the energytransition. This topic represents a challenge because it bears complex interrelations (technical,political,social) and strong polarization in debate. In order to achieve a compelling game experience as well as a learning outcome, we use a set of characters to represent different attitudes. While dealing with job-related and day‐to-day tasks, the characters run into the dilemma of foiling their commitment to sustainability. In the quest of a balance between consumption and happiness, they have to make energy-aware decisions and ooperate with eachother.

Aerodynamic shape optimisation with gradient-based methods is rapidly gaining popularity in the aerospace and automotive industries. The most effective method to compute the required sensitivities is the adjoint method which allows to compute sensitivities of an arbitrary number of design variables at constant computational cost. This in turn opens up a wide range of possibilities to parametrise the shape as the number of design variables is no longer a limiting factor as long as the parametrisation algorithm can also have differentiated in reverse mode. A wide range of parametrisations have been proposed for aerodynamic shape optimisation [1]. On the one hand we will consider a node-based parametrisation which uses the surface nodes of the CFD grid as design variables. On the other hand, we will consider CAD-based parametrisations based on open-source CAD-kernel OpenCascade Technology (OCCT). Adjoint methods do not penalise the size of the design space, hence we can consider very large spaces that guarantee to incorporate the largest possible number of degrees of freedom. In this work, we use in-house compressible discrete adjoint solver, STAMPS [2], derived from the flow solver using the automatic differentiation (AD) tool Tapenade.