bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analytical Model for Two-Dimensional Electron Gas Charge Density in Recessed-Gate GaN High-Electron-Mobility Transistors
Authors: Sharbati Samaneh , Gharibshahian Iman , Ebel Thomas , Orouji Ali A. , Franke Wulf-Toke 
Published: April 2021

AbstractA physics-based analytical model for GaN high-electron-mobility transistors (HEMTs) with non-recessed- and recessed-gate structure is presented. Based on this model, the two-dimensional electron gas density (2DEG) and thereby the on-state resistance and breakdown voltage can be controlled by varying the barrier layer thickness and Al mole fraction in non-recessed depletion-mode GaN HEMTs. The analytical model indicates that the 2DEG charge density in the channel increases from 2.4 × 1012 cm−2 to 1.8 × 1013 cm−2 when increasing the Al mole fraction from x = 0.1 to 0.4 for an experimental non-recessed-gate GaN HEMT. In the recessed-gate GaN HEMT, in addition to these parameters, the recess height can also control the 2DEG to achieve high-performance power electronic devices. The model also calculates the critical recess height for which a normally-ON GaN switch becomes normally-OFF. This model shows good agreement with reported experimental results and promises to become a useful tool for advanced design of GaN HEMTS.
Diagnostik und Therapie der residualen Tagesschläfrigkeit bei Patienten mit therapierter obstruktiver Schlafapnoe
Authors: Fietze Ingo , Blum Hans-Christian , Grüger Hartmut , Käßner Frank , Maurer Joachim T. , Nilius Georg , Penzel Thomas , Triché Dora , Arzt Michael 
Published: April 2021

ZusammenfassungDie residuale Tagesschläfrigkeit tritt bei 12–65 % der Schlafapnoe-Patienten unter eingeleiteter Positivdrucktherapie („positive airway pressure“) auf. Eine häufige Ursache ist die geringe PAP-Nutzungszeit. Mögliche weitere Gründe sind ein hoher Rest-Apnoe-Hypopnoe-Index und eine vorhandene Komorbidität. Prädiktoren sind ein initial hoher Epworth-Schläfrigkeitsscore, jüngeres Alter und die erst kurze PAP-Nutzung. Gesichert wird die Restschläfrigkeit mittels objektiver Testverfahren (z. B. multipler Wachbleibetest oder Oxford Sleep Resistance Test [Osler-Test]). Eine der wesentlichen Ursachen für die residuale Schläfrigkeit nach Ausschluss konkurrierender Auslöser ist die stattgehabte intermittierende nächtliche Hypoxämie, die zu nervalen Zellschädigungen, zu hormonellen und genetischen Veränderungen und zu Änderungen des Mikrobioms führen kann.Die klinischen Beschwerden werden bestimmt durch eine ausgeprägte Tagesschläfrigkeit, depressive Verstimmung und eine Minderung der Lebensqualität.Nach Ausschluss möglicher therapiebedingter Ursachen kann die residuale Tagesschläfrigkeit medikamentös mit u. a. Modafinil, Armodafinil, Pitolisant oder Solriamfetol behandelt werden. Die genannten Arzneimittel haben unterschiedliche Wirkmechanismen. Die Studien und die Effekte der Substanzen auf die Tagesschläfrigkeit, die Lebensqualität und die Leistungsfähigkeit der Betroffenen werden vorgestellt. Das Nebenwirkungsprofil der Wirkstoffe ist ähnlich. Für die Indikation residuale Schläfrigkeit einer therapierten obstruktiven Schlafapnoe ist in Europa derzeit nur Solriamfetol zugelassen.Ein vom Autorenteam entworfener Behandlungspfad für Patienten mit therapierter obstruktiver Schlafapnoe mit residualer Tagesschläfrigkeit, von der Erstvorstellung nach Therapiebeginn über die Therapieoptimierung bis hin zu einer medikamentösen Behandlung, wird vorgestellt.
It takes two to tango: the interplay between decision logics, communication strategies and social media engagement in start-ups
Authors: Rudeloff Christian , Pakura Stefanie , Eggers Fabian , Niemand Thomas 
Published: April 2021

AbstractThis manuscript analyzes start-ups’ usage of different communication strategies (information, response, involvement), their underlying decision logics (effectuation, causation, strategy absence) and respective social media success. A multitude of studies have been published on the decision logics of entrepreneurs as well as on different communication strategies. Decision logics and according strategies and actions are closely connected. Still, research on the interplay between the two areas is largely missing. This applies in particular to the effect of different decision logics and communication models on social media success. Through a combination of case studies with fuzzy-set Qualitative Comparative Analysis this exploratory study demonstrates that different combinations of causal and absence of strategy decision logics can be equally successful when it comes to social media engagement, whereas effectuation is detrimental for success. Furthermore, we find that two-way-communication is essential to create engagement, while information strategy alone cannot lead to social media success. This study provides new insights into the role of decision logics and connects effectuation theory with the communication literature, a field that has been dominated by causal approaches.
Clustering activity at Mt Etna based on volcanic tremor: A case study
Authors: Nunnari Giuseppe 
Published: April 2021

AbstractThis paper deals with the classification of volcanic activity into three classes, referred to as Quite, Strombolian and Paroxysm. The main purpose is to give a measure of the reliability with which such a classification, typically carried out by experts, can be performed by Machine Learning algorithms, by using the volcanic tremor as a feature. Both supervised and unsupervised methods are considered. It is experimentally shown that at least the Paroxysm activity can be reliably classified. Performances are rigorously assessed, in comparison with the classification made by expert volcanologists, in terms of popular indices such as thef1-score and the Area under the ROC curve (AuC). The work is basically a case study carried out on a dataset recorded in the area of the Mt Etna volcano. However, as volcanic tremor is a geophysical signal widely available, considered methods and strategies can be easily applied to similar volcanic areas.
On diverse arts: crucible metallurgy and the polymetallic cycle at Scandinavia’s earliest Viking town, Ribe (8th–9th c. CE), Denmark
Authors: Orfanou V. , Birch T. , Sindbæk S. M. , Feveile C. , Barfod G. H. , Lesher C. E. 
Published: April 2021

AbstractThis study presents results from the analytical investigation of the polymetallic, non-ferrous metallurgical cycle at early Viking Age Ribe, Denmark, in the 8th and 9th centuries CE. We combine extensive surface analyses of crucibles and moulds (handheld XRF) with targeted micro-destructive examination (micro XRF, electron microprobe spectroscopy—EPMA) of crucibles, moulds, ingots, blanks, and finished objects from the different stages of the secondary metallurgical production. Results show the working of a range of copper alloys with (leaded) brass as the most common, alongside small-scale working of silver and gold. Analytical evidence suggests a move towards technological standardisation at Ribe workshops from the pre-Viking period to the early Viking Age as reflected in the tighter compositional groupings for the crucible fabrics, the alloy choices for specific artefact types, e.g. keys and brooches, and an overall move towards high Zn brass from the 8th century to the first half of the 9th century CE. Finally, we discuss the limitations and potentials of the surface and micro-destructive analytical methods used and the insights gained from each data set and propose a direction for future research.
On the dimension of totally geodesic submanifolds in the Prym loci
Authors: Colombo Elisabetta , Frediani Paola 
Published: April 2021

AbstractIn this paper we give a bound on the dimension of a totally geodesic submanifold of the moduli space of polarised abelian varieties of a given dimension, which is contained in the Prym locus of a (possibly) ramified double cover. This improves the already known bounds. The idea is to adapt the techniques introduced by the authors in collaboration with A. Ghigi and G. P. Pirola for the Torelli map to the case of the Prym maps of (ramified) double covers.
Enhanced Wastewater Treatment by Immobilized Enzymes
Authors: Zdarta Jakub , Jankowska Katarzyna , Bachosz Karolina , Degórska Oliwia , Kaźmierczak Karolina , Nguyen Luong N. , Nghiem Long D. , Jesionowski Teofil 
Published: April 2021

Abstract
Purpose of Review
In the presented review, we have summarized recent achievements on the use of immobilized oxidoreductases for biodegradation of hazardous organic pollutants including mainly dyes, pharmaceuticals, phenols, and bisphenols. In order to facilitate process optimization and achievement of high removal rates, effect of various process conditions on biodegradation has been highlighted and discussed.

Recent Findings
Current reports clearly show that immobilized oxidoreductases are capable of efficient conversion of organic pollutants, usually reaching over 90% of removal rate. Further, immobilized enzymes showed great recyclability potential, allowing their reuse in numerous of catalytic cycles.

Summary
Collected data clearly indicates immobilized oxidoreductases as an efficient biocatalytic tools for removal of hazardous phenolic compounds, making them a promising option for future water purification. Data shows, however, that both immobilization and biodegradation conditions affect conversion efficiency; therefore, process optimization is required to achieve high removal rates. Nevertheless, we have demonstrated future trends and highlighted several issues that have to be solved in the near-future research, to facilitate large-scale application of the immobilized oxidoreductases in wastewater treatment.
Adaptive dynamic programming-based feature tracking control of visual servoing manipulators with unknown dynamics
Authors: Ren Xiaolin , Li Hongwen 
Published: April 2021

AbstractThis paper investigates a feature tracking control method for visual servoing (VS) manipulators adaptive dynamic programming (ADP)-based the unknown dynamics. The major superiority of ADP-based optimal control lies in that the visual tracking problem is converted to the feature tracking error control with optimal cost function. Moreover, an adaptive neural network observer is developed to approximate the entire uncertainties, which are utilized to construct an improved cost function. By establishing a critic neural network, the Hamilton–Jacobi–Bellman (HJB) equation is solved, and the approximate optimal error control policy is derived. The closed-loop VS manipulator system is verified to be ultimately uniformly bounded with the developed ADP-based feature tracking control strategy according to the Lyapunov theory. Finally, simulation results under various situations demonstrate that the proposed method achieves higher tracking accuracy than other methods, as well as satisfies energy optimal requirements.
Sniffing Bacteria with a Carbon-Dot Artificial Nose
Authors: Shauloff Nitzan , Morag Ahiud , Yaniv Karin , Singh Seema , Malishev Ravit , Paz-Tal Ofra , Rokach Lior , Jelinek Raz 
Published: April 2021

Highlights

Novel artificial nose based upon electrode-deposited carbon dots (C-dots). Significant selectivity and sensitivity determined by “polarity matching” between the C-dots and gas molecules.

The C-dot artificial nose facilitates, for the first time, real-time, continuous monitoring of bacterial proliferation and discrimination among bacterial species, both between Gram-positive and Gram-negative bacteria and between specific strains.

Machine learning algorithm furnishes excellent predictability both in the case of individual gases and for complex gas mixtures.

Abstract
Continuous, real-time monitoring and identification of bacteria through detection of microbially emitted volatile molecules are highly sought albeit elusive goals. We introduce an artificial nose for sensing and distinguishing vapor molecules, based upon recording the capacitance of interdigitated electrodes (IDEs) coated with carbon dots (C-dots) exhibiting different polarities. Exposure of the C-dot-IDEs to volatile molecules induced rapid capacitance changes that were intimately dependent upon the polarities of both gas molecules and the electrode-deposited C-dots. We deciphered the mechanism of capacitance transformations, specifically substitution of electrode-adsorbed water by gas molecules, with concomitant changes in capacitance related to both the polarity and dielectric constants of the vapor molecules tested. The C-dot-IDE gas sensor exhibited excellent selectivity, aided by application of machine learning algorithms. The capacitive C-dot-IDE sensor was employed to continuously monitor microbial proliferation, discriminating among bacteria through detection of distinctive “volatile compound fingerprint” for each bacterial species. The C-dot-IDE platform is robust, reusable, readily assembled from inexpensive building blocks and constitutes a versatile and powerful vehicle for gas sensing in general, bacterial monitoring in particular.
Trust in the European Union project and the role of ECB
Authors: Liotti Giorgio , Canale Rosaria Rita 
Published: April 2021

AbstractWas the European Central Bank able to assure the relaunch of the European project after the weakening of the post-crisis period? To answer this question, this paper presents an empirical analysis connecting citizen trust in the European Union with a variable intended to be a measure of the monetary policy strategy of the European Central Bank, namely, the interest rate on government bonds extracted from the 1-year maturity yield curve. The dynamic panel technique, applied to nineteen Eurozone countries for the time span of 2004–2018, estimates the presence of a long-run common relationship between the variables despite allowing different short-run adjustment mechanisms. Results are revealed to be not univocal: the easy monetary policy strategy is associated for the whole period with a decline of trust, and therefore, despite its impressiveness, it was not sufficient to relaunch the European Union project. However, when considering the change in strategy of the post-2013 period, it seemed to have contributed to a slight inversion of the decline of trust. These results highlight the importance of non-conventional measures and call for further support from coordinated policy action as a response to the negative shock deriving from the COVID-19 pandemic.
Ein Epigone bekennt sich zu den Herausgebern der Gesamtausgabe der Werke von Friedrich List und sieht sich in deren Nachfolge
Authors: Wendler Eugen 
Published: April 2021

ZusammenfassungSeit 5 Jahrzehnten steht die Erforschung von Leben, Werk und Wirkungsgeschichte von Friedrich List (1789–1846) im Zentrum der wissenschaftlichen Arbeit von Eugen Wendler. Im Laufe der Zeit sind ca. 30 Monographien und eine größere Anzahl von wissenschaftlichen Aufsätzen und journalistischen Artikeln entstanden. Dabei baute Eugen Wendler auf der unschätzbaren Vorarbeit der Herausgeber der Gesamtausgabe von Lists Werken von 1925 bis 1935 auf.Der vorliegende Aufsatz vermittelt einen Überblick über die Buchpublikationen von Eugen Wendler zur List-Forschung. Mit seinem eindrucksvollen Oeuvre bekennt er sich zum letzten lebenden Fossil in der Nachfolge der FLG und erweist damit den Herausgebern die gebührende und längst überfällige Wertschätzung und Achtung.
Physical stabilization of expansive subgrade soil using locally produced geogrid material
Authors: Aga Samson Yonas 
Published: April 2021

AbstractThis paper illustrates application of a locally produced geogrid material for strength improvement of expansive subgrade soil. Samples of black, soft soil predominating the study area were collected from south western parts of Modjo town, inside the rift valley region of central parts of Ethiopia. X-Ray diffraction as well as index property tests were executed to identify and categorize the expansiveness of the highly plastic soft soil. The effects of two locally manufactured geogrid reinforcement materials; namely, polypropylene (PP) and high density polyethylene (HDPE) on the California bearing ratio (CBR) values of the expansive soil have been investigated. The test results indicated that the use of the geogrid reinforcement can significantly improve the bearing capacity of weak subgrade soil. The soaked CBR of the untreated soil sample, which was about 2.98%, was able to be raised to 10.16% and 7.48% by the application of PP and HDPE type of geogrid respectively, that were placed at 0.35H from the top of specimen. The research demonstrated the potential of using locally produced geogrid material for the improvement of weak subgrade soil.
Gaussian Based Non-linear Function Approximation for Reinforcement Learning
Authors: Haider Abbas , Hawe Glenn , Wang Hui , Scotney Bryan 
Published: April 2021

AbstractReinforcement learning (RL) problems with continuous states and discrete actions (CSDA) can be found in classic examples such as Cart Pole and Puck World, as well as real world applications such as Market Making. Solutions to CSDA problems typically involve a function approximation (FA) of the mapping from states to actions and can be linear or nonlinear. Linear FAs such as tile-coding (Sutton and Barto in Reinforcement learning, 2nd ed, 2009) suffer from state information loss due to state discretization, whilst non-linear FAs such as DQN (Mnih et al. in Playing atari with deep reinforcement learning,https://arxiv.org/abs/1312.5602, 2013) are practically infeasible in infinitely large state spaces due to their cubic time complexity ($$O(n^3)$$O(n3)). In this paper, we propose a novel, general solution to CSDA problems, called Gaussian distribution based non-linear function approximation (GBNLFA). Experimentation on three CSDA RL problems (Cart Pole, Puck World, Market Marking) demonstrates the superiority of GBNLFA over state-of-the-art FAs, namely tile-coding and DQN. In particular, GBNLFA resolves the state information loss problem with linear FAs and provides an asymptotically faster algorithm (O(n)) than linear FAs ($$O(n^2)$$O(n2)) and neural network based nonlinear FAs ($$O(n^3)$$O(n3)).
The Burden of Illness of Migraine in Canada: New Insights on Humanistic and Economic Cost
Authors: Amoozegar Farnaz , Khan Zaeem , Oviedo-Ovando Mariana , Sauriol Stephanie , Rochdi Driss 
Published: April 2021

ABSTRACT:Background:The aim of this study was to characterize the burden of illness of migraine in Canada. The primary objective was to estimate the annual direct medical resource use and associated costs in migraine patients who failed at least two prophylactic therapies for migraine.Methods:Adults with at least four migraine days per month and who had failed at least two prophylactic migraine therapies were included. Participation in a clinical trial within 12 months of enrollment was the sole exclusionary criterion. Patient demographic and clinical characteristics, migraine-related treatment and medical history, and direct medical resource utilization were collected through a retrospective medical chart review. Data on patient characteristics, lifestyle factors, treatments, medical resource utilization, out-of-pocket expenses, and indirect costs were collected through a cross-sectional patient survey. The patient survey also included validated patient-reported outcome instruments to assess migraine impact on quality of life and work productivity loss.Results:In total, 287 migraine patients were included. The mean time since migraine diagnosis was 14.3 years and patients experienced a mean of 14.1 migraine days per month. The total estimated annual cost of chronic migraine (CM) was $25,669 per patient, while the annual total costs for high-frequency episodic and low-frequency episodic migraine (EM) were estimated to be $24,885 and $15,651, respectively.Conclusion:Migraine is associated with moderate to severe disability. This results in substantial economic burden, directly from healthcare costs such as prescription medications and indirectly through lost work productivity. We also observed that patients with high-frequency EM experience significant burden, similar to that observed for patients with CM.
Auctions and the Making of the Nabob in Late Eighteenth-Century Calcutta and London
Authors: Rasico Patrick D. 
Published: April 2021

AbstractThis article examines the meanings and controversies surrounding sales by public auction in British colonial Calcutta and in London during the last decades of the eighteenth century. For Britons living in Calcutta's European sector, auctions were essential for acquiring imported European items that granted a sense of gentility and Britishness abroad. Public sales in Calcutta provided Britons with goods that instilled the fantasy of living in a British geography in India. However, by the last quarter of the century, ‘sales by hammer’ throughout the colonial world carried association with corruption, cruelty, and orientalization in the metropolitan imagination. In Britain, textual and visual accounts circulated of Europeans transforming into debauched ‘nabobs’, of the horrors of American slave auctions, and of the British East India Company's use of public sales to defraud and abuse prominent Indians. For some metropolitan observers, sales by hammer were a deceitful means of seizing property and status from the traditional landed elite of India and Britain. British critics feared that colonial auction practices could become common in Britain and could lead to the upending of social hierarchization and the normalization of slavery in the metropolis.
Using social media data to assess the impact of COVID-19 on mental health in China
Authors: Zhu Yongjian , Cao Liqing , Xie Jingui , Yu Yugang , Chen Anfan , Huang Fengming 
Published: April 2021

Abstract

Background
The outbreak and rapid spread of coronavirus disease 2019 (COVID-19) not only caused an adverse impact on physical health, but also brought about mental health problems among the public.

Methods
To assess the causal impact of COVID-19 on psychological changes in China, we constructed a city-level panel data set based on the expressed sentiment in the contents of 13 million geotagged tweets on Sina Weibo, the Chinese largest microblog platform.

Results
Applying a difference-in-differences approach, we found a significant deterioration in mental health status after the occurrence of COVID-19. We also observed that this psychological effect faded out over time during our study period and was more pronounced among women, teenagers and older adults. The mental health impact was more likely to be observed in cities with low levels of initial mental health status, economic development, medical resources and social security.

Conclusions
Our findings may assist in the understanding of mental health impact of COVID-19 and yield useful insights into how to make effective psychological interventions in this kind of sudden public health event.
Kierkegaard's Socratic Alternative to Hegel inFear and Trembling
Authors: Dinan Matthew 
Published: April 2021

AbstractSøren Kierkegaard'sFear and Tremblinghas traditionally attracted interest from scholars of political theory for its apparent hostility to political philosophy, and more recently for its compatibility with Marxism. This paper argues for a reconsideration of Kierkegaard's potential contributions to political theory by suggesting that the work's shortcomings belong to its pseudonymous author, Johannes de Silentio, and are in fact intended by Kierkegaard. Attentiveness to the literary development of the pseudonym allows us to see a Kierkegaard who is a deeper and more direct critic of Hegel's political philosophy than is usually presumed. By creating a pseudonym whose argument ultimately fails, Kierkegaard employs Socratic irony in order to point readers to the need to recover Socratic political philosophy as the appropriate adjunct to the faith of Abraham, and as an alternative to Hegelian, and post-Hegelian, political thought.