bluuebunny/crossref_metadata_2025 huggingface dataset:
Social Mobility from a Comparative Perspective Between Europe and Latin America
Authors: Fachelli Sandra , Marqués-Perales Ildefonso , Boado Marcelo , Solís Patricio
Published: November 2020

This chapter presents a review of the analysis of social mobility in the international sphere (Europe and Latin America), with a particular focus on the partner countries of the INCASI network. To date, few studies have linked nations whose economic and social aspects are so dissimilar.

As is usual in the specialized literature, the relationship between social origin and class destination is addressed. This is done by noting the comparisons made across the geographical areas. We review the analyses that have been made of the evolution of social fluidity as well as the distance between social classes within each country and the comparisons made between them.

We compare the main theories that have inspired the study of social mobility to date: modernization theory, which predicts an increase in relative mobility rates, and invariance theory, which postulates the constancy of social fluidity. Special attention is devoted to the role played by the family, the state and the market in late industrialized countries.

We study the difficulties for social change, i.e. upward mobility from one class to another, as well as the likelihood of reproduction in comparative terms. To do so, we link these mechanisms with the AMOSIT model. The advances in methodology, techniques, theory and data processing are highlighted.
Corporate Digital Entrepreneurship: Leveraging Industrial Internet of Things and Emerging Technologies
Authors: Ghosh Swapan , Hughes Mathew , Hughes Paul , Hodgkinson Ian
Published: November 2020

Industrial firms are under severe pressure to innovate by leveraging the industrial Internet of things (IIoT) and emerging digital technologies. Digital entrepreneurship for existing organizations (corporate digital entrepreneurship) is a key differentiating factor in a highly competitive and disruptive environment. However, there is limited guidance for corporate digital entrepreneurship and industrial managers do not have a conceptual framework to navigate their organizations for new product and process innovation. This paper discusses the importance of emerging digital technologies for digital entrepreneurship and presents a conceptual framework of corporate digital entrepreneurship highlighting three elements—business model transformation, operating model transformation, and cultural transformation—which is necessary for fostering digital entrepreneurship in organizations. The chapter presents three case studies and discusses practical implications for the future.
New Sources of Entrepreneurial Finance
Authors: Lynn Theo , Rosati Pierangelo
Published: November 2020

Digital technologies are transforming entrepreneurial finance. Near-ubiquitous access to the Internet, platformisation, and advances in cloud computing, machine learning and artificial intelligence, and blockchain are changing the sources, basis, and quantum of funding in ways that were unimaginable at the turn of the century. This chapter outlines the changes to the market for entrepreneurial finance from the perspective of structure and participants. The key sources and characteristics of alternative sources of finance available to entrepreneurs, including start-ups, are presented. Two online alternative finance sources, crowdfunding and token offerings, are discussed in greater detail. These are illustrated with case studies. This chapter concludes with recommendations and a discussion of practical implications.
Pursuing International Opportunities in a Digitally Enabled World
Authors: Song Di , Wu Aiqi
Published: November 2020

Digitalization has tremendously challenged how international opportunities are created and captured. Inspired by researches in the field of both entrepreneurship and international business, this study provides a comprehensive framework toward the impact of digital technologies (DTs) on opportunity pursuit in foreign markets. We identify two perspectives of DTs, i.e., DTs as ‘driving force’ and DTs as ‘disrupting force,’ which characterize DTs as a catalyst of experiential knowledge acquisition, and as a factor altering the relative significance of experiential knowledge to opportunity pursuit, respectively. By bridging these two perspectives with the notion of market-specific knowledge and general knowledge within internationalization process theory, some arguments with regard to what specific influences DTs play on international opportunity pursuit are further introduced. We hope this study can potentially offer some nuances to both practitioners as well as the research in the interaction of digitalization and international opportunity.
Challenges and Opportunities for Digital Entrepreneurship in Developing Countries
Authors: Samara Georges , Terzian Jessica
Published: November 2020

This chapter explores the obstacles and opportunities that digital entrepreneurs encounter when they operate in developing countries. Drawing on the varieties of institutional systems framework and on three interviews (two digital entrepreneurs and one consultant), this chapter chalks out the idiosyncratic challenges and opportunities for digital entrepreneurs operating in a developing context. Our findings indicate that digital entrepreneurs face a weak institutional infrastructure and an environment characterized by corruption that obstructs their operations. These weak infrastructures result in the inaccessibility to necessary start-up funds, the lack of policies and regulations that protect and support e-commerce, a weak digital infrastructure, and to a deficiency in digitally competent and experienced labor capital. At the same time, our findings indicate some opportunities stemming from the unique institutional setting in which digital entrepreneurs operate. The opportunities translate into the use of family wealth as a source of start-up financial capital, the use of personal connections as a source of social and human capital, and the rising education on digital entrepreneurship and its benefits. We conclude with some suggestions to improve the current institutional infrastructure for digital entrepreneurs in developing countries.
Unleashing the Creativity of Entrepreneurs with Digital Technologies
Authors: Hisrich Robert D. , Soltanifar Mariusz
Published: November 2020

For decades, creativity has been used to generate ideas among entrepreneurs and their teams. Although extensive research has been conducted on creativity, the majority of studies have focused on traditional ways of stimulating creativity, such as focus groups, the collective notebook method, brainstorming, brainwriting, reverse brainstorming and problem inventory analysis. However, the digital age appears to challenge much of this existing work on the nature of creativity. It is clear that online creativity and audiences are affecting the meaning, expression and impact of creativity. The traditional techniques of stimulating creativity have been replaced and aided by technology-driven innovations, such as artificial intelligence (AI), virtual reality (VR) and the Internet of things (IoT). This chapter explores ways to activate the creativity of entrepreneurs and their teams through the use of digital technologies. We believe that this chapter provides a rich source of examples on how technology is currently being used to support creativity by encouraging entrepreneurs and their teams to make connections, develop ideas, create meaning, collaborate and communicate. We present, in detail, three case studies and discuss practical implications for the future.
Development and Validation of Platform Businesses in Digital Entrepreneurship
Authors: Göcke Lutz , Meier Philip
Published: November 2020

Platform business models grow in relevance in nearly every industry by an optimization of transaction costs or a significant increase in innovativeness. Many entrepreneurs choose platform business models to create and capture value. Although the benefits of platform business models demonstrably have immense growth potential, these business models are also accompanied by unique challenges for startups in their early stages of development. In this chapter, we aim to discuss the specific challenges that digital entrepreneurs face when validating their platform business model concept. We also develop a processual model, based on the venture pyramid (discussed in Chap. 10.1007/978-3-030-53914-6_4  of this book) to validate the critical assumptions of platform business models. Based on three case studies of early-stage startups, we shed light on the dynamics of testing platform business models and discuss different approaches to develop a minimum viable platform.
Blockchain as an Approach for Secure Data Storage on Digital Consulting Platforms
Authors: Gerth Sebastian , Heim Lars
Published: November 2020

This chapter examines the concept of data security in a society increasingly shaped by digital technologies. We show how secure data storage can be optimised regarding digital documentation in the implementation of health-related service offers based on established procedures. Security and privacy of data are therefore particularly important in this subject area since highly sensitive data is stored and processed during health-related online consultations. The advent of blockchain technology provides a valuable opportunity to create trust in digital platforms. After relevant concepts and terms have been clarified, the functionality of the blockchain in general, as well as the different types, will be discussed. From this, options for the use of online consulting are developed and illustrated on the basis of three use cases.
The Role of an Entrepreneurial Mindset in Digital Transformation-Case Study of the Estonian Business School
Authors: Kooskora Mari
Published: November 2020

This chapter focuses on entrepreneurial mindset in digital transformation and presents a short case study about leading the digital transformation in one Estonian private business school, where the ongoing digital process has changed the organisation itself and also the ways how students are taught and trained for coping and leading in the digital world. In order to better understand the context and environment, a brief introduction to the digitalisation topic and slightly more detailed overview of digitalising in higher education sector is provided first.
Digital Creativity: Upgrading Creativity in Digital Business
Authors: Smailhodžić Edin , Berberović Denis
Published: November 2020

Creativity has become one of the most important driving factors of today’s digital business environments. Businesses are increasingly looking for creative employees who can offer new and out-of-the-box solutions to existing problems. Companies go through the process of digital transformation by increasingly changing the ways in which they employ digital technologies and develop new digital business models that help to create and to capture value. Combined with a creative approach, companies have experienced a surge in creative digital solutions. However, the creative process is not a self-perpetuating mechanism. It must be initiated and supported by organizations. This is done by understanding the creative process itself and by making small but fruitful adjustments to the work environment and the overall management of the workforce. As three chosen real-life examples will illustrate, such approach results in unleashing powerful creative energy that offers new services to the market, new approaches to solving existing problems, or as seen in the case of Uber—bringing in a completely new business model based on creative solutions and innovative approaches to different aspects of business operations.
Was ist Ökonomie? Das Interdisziplinäre Studentische Kolloquium (ISK) an der Humboldt-Universität zu Berlin
Authors: Breljak Anja , Kersting Felix , Miersch Klaas , Stieglitz Timo , Wohnsiedler Iris
Published: November 2020

Das Interdisziplinäre Studentische Kolloquium (ISK) ist ein seit 2013 an der Humboldt-Universität zu Berlin stattfindendes wöchentliches Format zur kritischen Diskussion von Ökonomietheorien und anderen wissenschaftlichen Ansätzen, die sich mit ökonomischen Fragen auseinandersetzen. Das ISK verfolgt dabei drei Ziele: 1) VWL stärker als politische Ökonomie zu verstehen, 2) interdisziplinäre Zugänge zu fördern und 3) die Teilnehmerinnen und Teilnehmer zu empowern. Für die Umsetzung dieser Ziele haben sich eine offene und inklusive Atmosphäre als ebenso förderlich erwiesen wie der Ansatz des selbstbestimmten und autodidaktischen Lernens. Die dauerhafte Schaffung eines Diskussions- und Reflexionsraums nach geisteswissenschaftlichem Vorbild führte unter anderem zu weiteren studentischen Seminaren und einigen veröffentlichten Texten.
Poetry-Slams als Impuls für eine subjektiv begründete Reflexion wirtschaftswissenschaftlicher Denk- und Sprachkulturen
Authors: Hahn Gabriela , Hantke Harald , Fischer Andreas
Published: November 2020

Poetry Slams sind nicht nur unterhaltsam, auch machen sie Lyrik – und damit unterschiedliche sprachliche Ebenen – einem breiteren Publikum zugänglich. Doch birgt ihre Erarbeitung und Präsentation im Rahmen des wissenschaftlichen Hochschulstudiums auch das Potenzial, Bildungsprozesse anzustoßen, die Studierenden die Möglichkeit bieten, drängende gesellschaftliche Probleme zu reflektieren, einzuordnen, wissenschaftlich zu erörtern oder gar zu lösen? Oder anders gefragt: Bieten Poetry-Slams Studierenden die Möglichkeit, (sozio-)ökonomische Themen orientierend, reflektierend und verantwortungsvoll in ihrer eigenen Sprache zu erschließen und sich gemeinsam mit anderen intersubjektiv darüber auszutauschen? Einblicke in die Beantwortung dieser Fragen bietet der vorliegende Beitrag, der ein konkretes Lehr-Lern-Arrangement skizziert, durch das Studierende des Masterstudiengangs „Lehramt an berufsbildenden Schulen – Fachrichtung Wirtschaftswissenschaften“ dazu herausgefordert wurden, eigene Poetry-Slam-Texte zu erarbeiten, präsentieren und reflektieren.
AdS3 wormholes from a modular bootstrap
Authors: Cotler Jordan , Jensen Kristan
Published: November 2020

Abstract

In recent work we computed the path integral of three-dimensional gravity with negative cosmological constant on spaces which are topologically a torus times an interval. Here we employ a modular bootstrap to show that the amplitude is completely fixed by consistency conditions and a few basic inputs from gravity. This bootstrap is notably for an ensemble of CFTs, rather than for a single instance. We also compare the 3d gravity result with the Narain ensemble. The former is well-approximated at low temperature by a random matrix theory ansatz, and we conjecture that this behavior is generic for an ensemble of CFTs at large central charge with a chaotic spectrum of heavy operators.
Model-dependence of minimal-twist OPEs in d > 2 holographic CFTs
Authors: Fitzpatrick A. Liam , Huang Kuo-Wei , Meltzer David , Perlmutter Eric , Simmons-Duffin David
Published: November 2020

Abstract

Following recent work on heavy-light correlators in higher-dimensional conformal field theories (CFTs) with a large central charge CT, we clarify the properties of stress tensor composite primary operators of minimal twist, [Tm], using arguments in both CFT and gravity. We provide an efficient proof that the three-point coupling $$ \left\langle {\mathcal{O}}_L{\mathcal{O}}_L\left[{T}^m\right]\right\rangle $$

O
L

O
L

T
m

, where $$ {\mathcal{O}}_L $$

O
L

is any light primary operator, is independent of the purely gravitational action. Next, we consider corrections to this coupling due to additional interactions in AdS effective field theory and the corresponding dual CFT. When the CFT contains a non-zero three-point coupling $$ \left\langle TT{\mathcal{O}}_L\right\rangle $$

TT

O
L

, the three-point coupling $$ \left\langle {\mathcal{O}}_L{\mathcal{O}}_L\left[{T}^2\right]\right\rangle $$

O
L

O
L

T
2

is modified at large CT if $$ \left\langle TT{\mathcal{O}}_L\right\rangle \sim \sqrt{C_T} $$

TT

O
L

∼

C
T

. This scaling is obeyed by the dilaton, by Kaluza-Klein modes of prototypical supergravity compactifications, and by scalars in stress tensor multiplets of supersymmetric CFTs. Quartic derivative interactions involving the graviton and the light probe field dual to $$ {\mathcal{O}}_L $$

O
L

can also modify the minimal-twist couplings; these local interactions may be generated by integrating out a spin-ℓ ≥ 2 bulk field at tree level, or any spin ℓ at loop level. These results show how the minimal-twist OPE coefficients can depend on the higher-spin gap scale, even perturbatively.
Reduktion der Tinnituslautstärke
Authors: Schilling A. , Krauss P. , Hannemann R. , Schulze H. , Tziridis K.
Published: November 2020

Hintergrund

Tinnitus betrifft ca. 15 % der Bevölkerung, jedoch existiert noch immer kein echtes Heilverfahren. Ein von uns entwickeltes neuartiges Erklärungsmodell erlaubt nun die Erprobung einer gezielten, an den Ursachen der Tinnitusentstehung ansetzenden Behandlung. Diese basiert auf stochastischen Resonanzphänomenen an bestimmten synaptischen Verbindungen im Hörsystem, welche gezielt durch extern zugeführtes schwellennahes Rauschen induziert werden sollen.

Fragestellung

Die vorliegende Pilotstudie soll zeigen, ob ein spektral individuell angepasstes Rauschen erfolgreich chronischen tonalen/schmalbandigen Tinnitus während der Stimulation abschwächen kann.

Material und Methoden

Bei 22 volljährigen Tinnituspatienten (46.6±16.3 Jahre; 4 Frauen) wurden Hörverlust (HV) sowie Tinnitusfrequenzen (TF) und -lautstärken (TL) audiometrisch bestimmt. Darauf basierend wurden bis zu 8 verschiedene Rauschstimuli (RS) mit je 5 Lautstärken (−20 bis +20 dB SL) erzeugt. Diese wurden über audiologische Kopfhörer in einer Schallkammer für jeweils 40 s präsentiert. Nach jeder Präsentation wurde mithilfe einer 5‑stufigen Bewertungsskala (−2 bis +2) ermittelt, ob sich die TL verändert hat.

Ergebnisse

Es fanden sich Patienten ohne Verbesserung der TL (n = 6) und solche mit Verbesserung (n = 16), wobei hier RS um die TF besonders effektiv waren. Die Gruppen zeigten post hoc deutliche Unterschiede in den Audiogrammen: Offenbar ist das hier getestete Verfahren insbesondere bei normalhörenden Tinnituspatienten und solchen mit geringgradigem HV effektiv.

Schlussfolgerung

Die subjektiv wahrgenommene TL war bei 16 von 22 Probanden für die Dauer der Stimulation reduziert. Für den möglichen Erfolg einer zukünftigen Therapie scheint der HV relevant zu sein.
On the Complexity of the Smallest Grammar Problem over Fixed Alphabets
Authors: Casel Katrin , Fernau Henning , Gaspers Serge , Gras Benjamin , Schmid Markus L.
Published: November 2020

In the smallest grammar problem, we are given a word w and we want to compute a preferably small context-free grammar G for the singleton language {w} (where the size of a grammar is the sum of the sizes of its rules, and the size of a rule is measured by the length of its right side). It is known that, for unbounded alphabets, the decision variant of this problem is NP-hard and the optimisation variant does not allow a polynomial-time approximation scheme, unless P = NP. We settle the long-standing open problem whether these hardness results also hold for the more realistic case of a constant-size alphabet. More precisely, it is shown that the smallest grammar problem remains NP-complete (and its optimisation version is APX-hard), even if the alphabet is fixed and has size of at least 17. The corresponding reduction is robust in the sense that it also works for an alternative size-measure of grammars that is commonly used in the literature (i. e., a size measure also taking the number of rules into account), and it also allows to conclude that even computing the number of rules required by a smallest grammar is a hard problem. On the other hand, if the number of nonterminals (or, equivalently, the number of rules) is bounded by a constant, then the smallest grammar problem can be solved in polynomial time, which is shown by encoding it as a problem on graphs with interval structure. However, treating the number of rules as a parameter (in terms of parameterised complexity) yields W[1]-hardness. Furthermore, we present an $\mathcal {O}(3^{\mid {w}\mid })$
O
(

3

∣
w
∣

)
exact exponential-time algorithm, based on dynamic programming. These three main questions are also investigated for 1-level grammars, i. e., grammars for which only the start rule contains nonterminals on the right side; thus, investigating the impact of the “hierarchical depth” of grammars on the complexity of the smallest grammar problem. In this regard, we obtain for 1-level grammars similar, but slightly stronger results.
The diagnostic value of magnetic resonance imaging in differentiating benign and malignant pediatric ovarian tumors
Authors: Janssen Carlijn L. , Littooij Annemieke S. , Fiocco Marta , Huige Josephine C. B. , de Krijger Ronald R. , Hulsker Caroline C. C. , Goverde Angelique J. , Zsiros József , Mavinkurve-Groothuis Annelies M. C.
Published: November 2020

Background

The diagnostic workup of ovarian tumors in children and adolescents is challenging because preserving fertility, in addition to oncological safety, is of particular importance in this population. Therefore, a thorough preoperative assessment of ovarian tumors is required.

Objective

To investigate the diagnostic value of MR imaging in differentiating benign from malignant ovarian tumors in children and adolescents.

Materials and methods

We conducted a retrospective study of all children and adolescents age <18 years who underwent MR imaging of ovarian tumors during 2014–2019 at a pediatric specialty center. Two radiologists reviewed all MR imaging. We used pathology reports to define the histological diagnosis.

Results

We included 30 girls who underwent MR imaging for an ovarian tumor. Signs indicative for malignancy were tumors with a diameter ≥8 cm, with areas of contrast enhancement, irregular margins, extracapsular tumor growth, and ascites. All benign and malignant ovarian tumors were correctly identified by the radiologists.

Conclusion

The diagnostic utility of MR imaging in classifying ovarian tumors in children and adolescents as benign or malignant is promising and might aid in defining the indication for ovarian-sparing versus non-ovarian-sparing surgery. We recommend evaluating these tumors with MR imaging prior to deciding on surgical treatment.
Probing the effect of aroma compounds on the hydrodynamic properties of mucin glycoproteins
Authors: Dinu Vlad , MacCalman Thomas , Yang Ni , Adams Gary G. , Yakubov Gleb E. , Harding Stephen E. , Fisk Ian D.
Published: November 2020

Aroma compounds are diverse low molecular weight organic molecules responsible for the flavour of food, medicines or cosmetics. Natural and artificial aroma compounds are manufactured and used by the industry to enhance the flavour and fragrance of products. While the low concentrations of aroma compounds present in food may leave no effect on the structural integrity of the mucosa, the effect of concentrated aroma volatiles is not well understood. At high concentrations, like those found in some flavoured products such as e-cigarettes, some aroma compounds are suggested to elicit a certain degree of change in the mucin glycoprotein network, depending on their functional group. These effects are particularly associated with carbonyl compounds such as aldehydes and ketones, but also phenols which may interact with mucin and other glycoproteins through other interaction mechanisms. This study demonstrates the formation of such interactions in vitro through the use of molecular hydrodynamics. Sedimentation velocity studies reveal that the strength of the carbonyl compound interaction is influenced by compound hydrophobicity, in which the more reactive short chain compounds show the largest increase in mucin-aroma sedimentation coefficients. By contrast, the presence of groups that increases the steric hindrance of the carbonyl group, such as ketones, produced a milder effect. The interaction effects were further demonstrated for hexanal using size exclusion chromatography light scattering (SEC-MALS) and intrinsic viscosity. In addition, phenolic aroma compounds were identified to reduce the sedimentation coefficient of mucin, which is consistent with interactions in the non-glycosylated mucin region.
Precipitation response to extreme soil moisture conditions over the Mediterranean
Authors: Ardilouze Constantin , Materia Stefano , Batté Lauriane , Benassi Marianna , Prodhomme Chloé
Published: November 2020

The intimate link between soil moisture and precipitation makes it a “chicken-and-egg situation” that challenges climate studies of the continental water cycle. This association is particularly acute over the Mediterranean, increasingly exposed to droughts with climate change. This study aims at deciphering the impact of spring soil moisture state in the Mediterranean on subsequent warm season precipitation. In an idealized setup, two distinct climate models are used to generate extreme dry or wet soil conditions, and run climate simulations initialized and/or forced by these conditions. Changes in precipitation distribution and persistence are analyzed and where applicable compared to composites from a reanalysis. Spring soil moisture anomalies are found to be very persistent, but the precipitation response is largely model dependent. Overall, dry soils lead to a reduction of precipitation for early summer months and conversely for wet soils although with a fainter and less robust signal. On the other hand, wet soils tend to favor the persistence of precipitation throughout summer over several sub-regions. Our results highlight the stringent need to reduce the wide array of uncertainties associated to soil moisture, land-atmosphere coupling and convection in climate models, before ascertaining that soil moisture initialization could provide more skillful sub-seasonal to seasonal precipitation prediction.
Comparison of mechanical circulatory support with venoarterial extracorporeal membrane oxygenation or Impella for patients with cardiogenic shock: a propensity-matched analysis
Authors: Karatolios Konstantinos , Chatzis Georgios , Markus Birgit , Luesebrink Ulrich , Ahrens Holger , Divchev Dimitar , Syntila Styliani , Jerrentrup Andreas , Schieffer Bernhard
Published: November 2020

Background

Percutaneous mechanical circulatory devices are increasingly used in patients with cardiogenic shock (CS). As evidence from randomized studies comparing these devices are lacking, optimal choice of the device type is unclear. Here we aim to compare outcomes of patients with CS supported with either Impella or vaECMO.

Methods

Retrospective single-center analysis of patients with CS, from September 2014 to September 2019. Patients were assisted with either Impella 2.5/CP or vaECMO. Patients supported ultimately with both devices were analyzed according to the first device implanted. Primary outcomes were hospital and 6-month survival. Secondary endpoints were complications. Survival outcomes were compared using propensity-matched analysis to account for differences in baseline characteristics between both groups.

Results

A total of 423 patients were included (Impella, n = 300 and vaECMO, n = 123). Survival rates were similar in both groups (hospital survival: Impella 47.7% and vaECMO 37.3%, p = 0.07; 6-month survival Impella 45.7% and vaECMO 35.8%, p = 0.07). There was no significant difference in survival rates, even after adjustment for baseline differences (hospital survival: Impella 50.6% and vaECMO 38.6%, p = 0.16; 6-month survival Impella 45.8% and vaECMO 38.6%, p = 0.43). Access-site bleeding and leg ischemia occurred more frequently in patients with vaECMO (17% versus 7.3%, p = 0.004; 17% versus 7.7%, p = 0.008).

Conclusions

In this retrospective analysis of patients with CS, treatment with Impella 2.5/CP or vaECMO was associated with similar hospital and 6-month survival rates. Device-related access-site vascular complications occurred more frequently in the vaECMO group. A randomized trial is warranted to examine the effects of these devices on outcomes and to determine the optimal device choice in patients with CS.
Correction to: Influence of Acid Swallows on the Dynamics of the Upper Esophageal Sphincter
Authors: Miller Simone , Ptok Martin , Jungheim Michael
Published: November 2020

The article “Influence of Acid Swallows on the Dynamics of the Upper Esophageal Sphincter”, written by “Simone Miller, Martin Ptok, Michael Jungheim”, was originally published electronically on the publisher’s internet portal on 4 September 2020 without open access. With the author(s)’ decision to opt for Open Choice the copyright of the article changed on 30 October 2020 to © The Author(s) 2020 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
The 3rd Level – Entwicklung der Feinstzerkleinerung und Ausbau der Flotation am Lehrstuhl für Aufbereitung und Veredlung
Authors: Böhm Andreas , Mayer Michael , Ressel Gerald
Published: November 2020

Im Februar dieses Jahres konnte der Lehrstuhl für Aufbereitung und Veredlung auf Basis von lehrstuhlinternen Forschungsarbeiten zur Zerkleinerungstechnik in Kooperation mit dem „Materials Center Leoben Forschung GmbH“ (MCL) die Laboratorien in den 3. Stock des Impulszentrums für Rohstoffe und damit um eine Gesamtfläche von ca. 175 m2 ausdehnen. Mit finanzkräftiger Unterstützung durch die Montanuniversität Leoben, die zwei Anträge der Lehrstuhlleitung (hausinterne Impulsprogramme) positiv bewertete, konnte die apparative Ausrüstung aufgebaut werden, um die Forschungsziele Energieoptimierte Feinstzerkleinerung <5 µm, Smart processing und Integrale Prozessführung „mill as reactor“ in Angriff zu nehmen. Daneben werden ein zusätzliches Flotationslabor und Räumlichkeiten für Analytik mit Ende des Jahres einsatzbereit sein.

Eine mobile Pilotanlage zur Rührwerkskugelmühlenmahlung und eine Labormühle für kryogene Mahlung sowie Mahlung bei erhöhtem Gasdruck sind die Anlagen, die in unterschiedlichen Forschungsprojekten erprobt, genutzt und zur Prozessreife geführt werden sollen.

Die technische Erweiterung erschließt dem Lehrstuhl die Feinstzerkleinerung, Anlagenauslegung, Automatisierung von Zerkleinerungsabläufen und Prozessentwicklung jenseits des herkömmlichen Einsatzes von Mühlen in der Primär- und Sekundärrohstoffaufbereitung.
The effects of art therapy on anxiety, depression, and quality of life in adults with cancer: a systematic literature review
Authors: Bosman J. T. , Bood Z. M. , Scherer-Rath M. , Dörr H. , Christophe N. , Sprangers M. A. G. , van Laarhoven H. W. M.
Published: November 2020

Purpose

While there is increasing evidence for the effectiveness of psychosocial support programs for cancer patients, little attention has been paid to creativity or art as a way of addressing their psychological problems and improving quality of life. This review provides an overview of interventional studies that investigate the effects of art therapy interventions on anxiety, depression, and quality of life in adults with cancer.

Methods

We conducted a literature review with a systematic search. The databases PubMed/MEDLINE, PsycINFO, and EMBASE were searched for articles on art therapy among adult (18 years and above) cancer patients, published between September 2009 up to September 2019. Search terms were established for each database specifically. A total of 731 publications was assessed for relevance by title and abstract. The remaining 496 articles were examined using three inclusion criteria: interventions were guided by an artist or art therapist, participants were actively involved in the creative process, and anxiety, depression, and/or quality of life were included as outcome measures. Methodological quality of the included studies was appraised using specific checklists.

Results

Seven papers met the inclusion criteria. Data was extracted from three non-randomized intervention studies and four randomized controlled trials. All studies used a quantitative design with validated outcome measures. Four articles described positive effects of art therapy on anxiety, depression, or quality of life in adults with cancer.

Conclusion

Art therapy could possibly help decrease symptoms of anxiety and depression, and improve quality of life in adult cancer patients. However, because of the heterogeneity of the interventions and limited methodological quality of the studies, further research using stringent methods is needed.
Tetraparesis and sensorimotor axonal polyneuropathy due to co-occurrence of Pompe disease and hereditary ATTR amyloidosis
Authors: Zimmermann Milan , Deininger Natalie , Willikens Sophia , Haack Tobias B. , Grundmann-Hauser Kathrin , Streubel Berthold , Schreiber Melanie , Lerche Holger , Grimm Alexander
Published: November 2020

Introduction/aims

Hereditary transthyretin amyloidosis with polyneuropathy (hATTRPN) is an autosomal dominant multi-organ disorder manifesting in the third to fifth decade with the key clinical features of distal and painful sensory loss of the lower limbs and autonomic dysregulation. Motor neuropathy and cardiomyopathy evolve in the course of the disease. Pompe disease is an autosomal recessive disease leading to decreased levels of lysosomal enzyme acid α-glucosidase and proximal muscle weakness. We report the clinical features and diagnostic workup in the rare case of a patient with ATTR amyloidosis and late-onset Pompe disease, both genetically confirmed.

Methods

We performed a detailed clinical assessment, exome sequencing, and biochemical measurements.

Results

The patient presented with a distal, painful hypaesthesia of both legs, a cardiomyopathy, and a muscle weakness in the form of a girdle-type pattern of the arms and legs at the beginning and a spreading to distal muscle groups in the course of disease.

Discussion

This study highlights the importance of searching for co-occurrence of rare monogenetic neuromuscular diseases, especially in cases in which all clinical features can be readily explained by a single gene defect.
Dynamic probabilistic constraints under continuous random distributions
Authors: González Grandón T. , Henrion R. , Pérez-Aros P.
Published: November 2020

The paper investigates analytical properties of dynamic probabilistic constraints (chance constraints). The underlying random distribution is supposed to be continuous. In the first part, a general multistage model with decision rules depending on past observations of the random process is analyzed. Basic properties like (weak sequential) (semi-) continuity of the probability function or existence of solutions are studied. It turns out that the results differ significantly according to whether decision rules are embedded into Lebesgue or Sobolev spaces. In the second part, the simplest meaningful two-stage model with decision rules from $$L^2$$

L
2

is investigated. More specific properties like Lipschitz continuity and differentiability of the probability function are considered. Explicitly verifiable conditions for these properties are provided along with explicit gradient formulae in the Gaussian case. The application of such formulae in the context of necessary optimality conditions is discussed and a concrete identification of solutions presented.
A 500-year history of forest fires in Sala area, central Sweden, shows the earliest known onset of fire suppression in Scandinavia
Authors: Pinto Guilherme Alexandre Stecher Justini , Niklasson Mats , Ryzhkova Nina , Drobyshev Igor
Published: November 2020

The Sala fire in the Västmanland County of central Sweden that burned about 14,000 ha in 2014 has been the largest fire recorded in the modern history of Sweden. To understand the long-term fire history of this area, we dendrochronologically dated fire scars on Scots pine (Pinus sylvestris L.) trees (live and deadwood) to reconstruct the fire cycle and fire occurrence in the area affected by the 2014 fire. We identified 64 fire years, using a total of 378 pine samples. The earliest reconstructed fire dated back to 1113 AD. The spatial reconstruction extended over the period of 1480–2018 AD. Lower levels of fire activity (fire cycle, FC = 43 years, with the central 90% of the distribution limited by 35 to 57 years) dominated in the earlier period (1480–1690 AD) that was followed by a strong decrease in fire activity since 1700 (FC = 403 years, with 90% of the distribution being within 149 to 7308 years), with a fire-free period between 1756 and 2014. Sala area, therefore, features the earliest known onset of fire suppression in Scandinavia. The high demand for timber during the peak in mining activities in the study area around the 1700–1800s, accompanied by passive fire suppression policies, were possibly the main drivers of the decline in fire activity. Superposed epoch analysis (SEA) did not show significant departures in the drought proxy during the ten years with the largest area burned between 1480 and1690. It is unclear whether the result is due to the relatively small area sampled or an indication that human controls of fires dominated during that period. However, significant departures during the following period with low fire activity (1700–1756), which just preceded the last fire-free period, suggested that the climate became an increasingly important driver of fire during the onset of the suppression period. We speculate that the lack of major firebreaks, the homogenization of forests, and the lack of burned areas with low fuel loads might contribute to the occurrence of the exceptionally large 2014 fire in Sala.
Environmental niche and functional role similarity between invasive and native palms in the Atlantic Forest
Authors: Bello Carolina , Cintra Ana Laura P. , Barreto Elisa , Vancine Maurício Humberto , Sobral-Souza Thadeu , Graham Catherine H. , Galetti Mauro
Published: November 2020

Invasive species can significantly affect native species when their niches are similar. Ecological and morphological similarities between the invasive Australian palm,Archontophoenix cunninghamiana,and the native palm from the Brazilian Atlantic Forest,Euterpe edulis, suggest that they have similar environmental requirements and functional roles (i.e., the function a species performs in an ecosystem). This similarity raises concerns about how the invasive palm could impact the native species in the present and future. We used spatial (species occurrences) and ecological information (frugivory events) to characterize the environmental niche and functional role of the two palms and assess their overlap. In addition, we predicted the potential area of occurrence of each palm within the Brazilian Atlantic Forest under current and future climate conditions.We estimated the environmental conditions used by the invasive plant based on its native distribution only, and based on all areas where the species is able to establish across the globe. We found that the environmental niches of the two palm species overlap up to 39%, which corresponds to 50% of the current geographic distribution of E. edulis in the Atlantic Forest. In the areas where the two species potentially co-occur, the impact of the invasive species on the native should be influenced by the invasive species interactions with frugivores. We found that the frugivory functional role of the two palms was similar (84% overlap) which suggest thatA. cunninghamianamight disrupt the seed dispersal of the native palm. However, co-occurrence between the palms may decline with future climate change, as the potentially environmental suitable area for the invasive palm is predicted to decline by 10% to 55%. Evaluating the similarity in both the environmental niche, of the native and global extent, and the functional role of native and invasive plants provides a detailed understanding of the potential impact of invasive species on native species now and in the future.
Social equity in supplier–buyer relationships in smallholder agri-food supply chains
Authors: Hernandez-Martinez Nayeli , Mutlu Nevin , Fransoo Jan C.
Published: November 2020

We study supplier–buyer relationships in smallholder agri-food supply chains with equity concerns and under stakeholder engagement. We develop a game theoretic model to study the impact of these socially responsible practices in investment and pricing decisions. We model this as a Stackelberg game and study the impacts of the power structure in the outcomes. Our work was motivated by the business model of socially responsible Mexican company Fractal Café. We provide closed form expressions for the optimal wholesale and retail prices, and numerically study the effect of the model parameters. We show that equity concerns drive a redistribution of the profit towards an equitable outcome, but they do not have the same effect on the investment decisions. Additionally, we show that equity concerns may reverse the advantage of the game leader and transfer utility to the follower. We identify the settings under which the introduction of socially responsible practices increases the total supply chain profit by reducing the double marginalization effect. We find that capacity constraints result in a higher retail price, achieved by increasing the leader’s margin. Finally, we show that a two-part tariff contract with equity concerns is only convenient for the game follower when the leader has a high concern for advantageous inequity.
Comparing the luminosity distance for gravitational waves and electromagnetic signals in a simple model of quadratic gravity
Authors: Fanizza G. , Franchini G. , Gasperini M. , Tedesco L.
Published: November 2020

We compute the modified friction coefficient controlling the propagation of tensor metric perturbations in the context of a generalized cosmological scenario based on a theory of gravity with quadratic curvature corrections. In such a context we discuss the differences between gravitational and electromagnetic luminosity distance, as well as the differences with the standard results based on the Einstein equations. We present numerical estimates of the modified luminosity distance on the cosmic redshift scale typical of Supernovae and standard sirens.
Challenging practical features of Bitcoin by the main altcoins
Authors: Spurr Andrew , Ausloos Marcel
Published: November 2020

We study the fundamental differences that separate: Litecoin; Bitcoin Gold; Bitcoin Cash; Ethereum; and Zcash from Bitcoin, and draw some analysis to how these features are appreciated by the market, to ultimately make an inference as to how future successful cryptocurrencies may be invented and behave. We use Google Trend data, as well as price, volume and market capitalization data sourced from coinmarketcap.com to support this analysis. We find that Litecoin’s shorter block times offer benefits in commerce, but drawbacks in the mining process through orphaned blocks. Zcash holds a niche use for anonymous transactions, benefitting areas of the world lacking in economic freedom. Bitcoin Cash suffers from centralization in the mining process, while the greater decentralization of Bitcoin Gold has generally left it to stagnate. Ether’s greater functionality offers the greatest threat to Bitcoin’s dominance in the market. A coin that incorporates several of these features can be technically better than Bitcoin, but the first-to-market advantage of Bitcoin should keep its dominant position in the market.
Chip formation in machining hybrid components of SAE1020 and SAE5140
Authors: Denkena B. , Breidenstein B. , Krödel A. , Prasanthan V.
Published: November 2020

The requirements for massive high-performance components are constantly increasing. In addition to the reduction of component weight, requirements such as smaller design, more functionality and longer lifetime are increasing. By joining different materials in one component, these contradictory requirements can be met. In the process chain of manufacturing hybrid components, machining as the final step has a decisive influence on the application behavior and service life due to the surface and subsurface properties generated. Thereby thermomechanical loads during machining determine the final subsurface properties and the chip formation mechanisms determine the final surface properties of components. However, for the specific adjustment of required surface and subsurface properties, first of all an understanding of the generation of the addressed properties in the material transition zone is necessary. In the current work, the chip formation and the mechanical loads in the transition zone of hybrid components are presented. Within the scope of orthogonal cutting investigations, the influence of process parameters and tool microgeometry on mechanical loads and chip formation is analyzed. Chip forming has a significant influence on the surface properties of the hybrid component. The chip formation depends on the hardness of the machined material. During machining of hybrid components an abrupt change of the chip shape takes place in the material transition zone. The process variables influence the level in the surface topography of hybrid components.
Combining Big Data and Artificial Intelligence for Managing Collective Knowledge in Unpredictable Environment—Insights from the Chinese Case in Facing COVID-19
Authors: Iandolo Francesca , Loia Francesca , Fulco Irene , Nespoli Chiara , Caputo Francesco
Published: November 2020

The increasing fluidity of social and business configurations made possible by the opportunities provided by the World Wide Web and the new technologies is questioning the validity of consolidated business models and managerial approaches. New rules are emerging and multiple changes are required to both individuals and organizations engaged in dynamic and unpredictable paths.

In such a scenario, the paper aims at describing the potential role of big data and artificial intelligence in the path toward a collective approach to knowledge management. Thanks to the interpretative lens provided by systems thinking, a framework able to explain human-machine interaction is depicted and its contribution to the definition of a collective approach to knowledge management in unpredictable environment is traced.

Reflections herein are briefly discussed with reference to the Chinese governmental approach for managing COVID-19 spread to emphasise the support that a technology-based collective approach to knowledge management can provide to decision-making processes in unpredictable environments.