bluuebunny/crossref_metadata_2025 huggingface dataset:
Copper metal‐organic framework toward flame‐retardant enhancement of thermoplastic polyurethane elastomer composites based on ammonium polyphosphate
Authors: Chen Xilei , Chen Xihong , Li Shaoxiang , Jiao Chuanmei
Published: April 2021

In this article, copper metal‐organic framework (MOF‐Cu) was synthesized and used as synergism with ammonium polyphosphate (APP) to prepare flame‐retardant thermoplastic polyurethane (TPU) composites. The synergistic flame‐retardant effects between MOF‐Cu and APP in TPU composites were studied by cone calorimeter (CCT), limiting oxygen index tests (LOI), vertical burning tests (UL‐94), smoke density test, etc. The results showed that MOF‐Cu had some flame‐retardant effects on TPU, and APP had good flame retardancy in TPU/APP composites. And, the flame retardancy of TPU/APP was further enhanced when MOF‐Cu was used as synergism with APP. It has been found that the peak heat release rate (pHRR) and total heat release (THR) values of TPU/Cu0.0625 sample were reduced by 26.0% and 1.3% compared with pure TPU, respectively. And the pHRR and THR values of TPU/APP sample were reduced by 70.3% and 15.8% compared with pure TPU. In the case of TPU/APP/Cu0.0625 sample, the pHRR and THR values were furtherly reduced by 19.2% and 63.4% compared with TPU/APP, because of the minor amount of MOF‐Cu. It has been found MOF‐Cu cannot suppress the smoke release and reduce the total smoke release (TSR) value. However, 0.125 wt% MOF‐Cu can make the TSR value of TPU/APP/Cu0.125 sample reduce to 227.8 m2/m2, which was 23.4% lower than that of TPU/APP. The good synergistic flame‐retardant effect between MOF‐Cu and APP was obtained by the catalyzing carbonization process to form the char residue layer with high graphitization and expansion degree.
Mechanical properties and foaming behavior of polypropylene/elastomer/recycled carbon fiber composites
Authors: Ghanbari Abbas , Seyedin Shayan , Nofar Mohammadreza , Ameli Amir
Published: April 2021

Research on lightweight products for transportation industry, to address fuel efficiency and lower carbon footprint, has attracted great attention due to public environmental awareness. Polymer composites containing carbon fiber are boosted by automotive original equipment manufacturers (OEMs) as a replacement for steel. However, their high cost has generated interest to find cost‐effective alternatives. In this report, a recycled carbon fiber and an elastomer are introduced to polypropylene impact copolymers to modify matrix properties in terms of strength and toughness. Fractography analysis is carried out to elucidate the failure mechanisms governing the mechanical performance of the compatibilized carbon fiber reinforced thermoplastic polyolefin (TPO) composites. The results suggest that for the TPO composites, toughened by an ethylene‐1‐octene copolymer, the complex interplay of intrinsic and extrinsic toughnesses in impact resistance is predominantly governed by the presence of the fibers. Incorporating 20 wt% recycled carbon fibers into the matrix resulted in an improvement of the heat distortion temperature (HDT) by 100 °C, and ~ 3.5 and ~ 11.5 times enhancements in tensile strength and stiffness, respectively. Moreover, microcellular foams with expansion ratios higher than 11 and 5 were achieved for the neat samples and reinforced composites, respectively, confirming the foamability of composites with such a high carbon fiber content.
Function‐based adaptive exponentially weighted moving average dispersion control chart
Authors: Arshad Asma , Noor‐ul‐Amin Muhammad , Hanif Muhammad
Published: April 2021

In this study, a new process dispersion monitoring control chart is proposed based on a function‐based adaptation to select the smoothing constant value, named as a function‐based adaptive exponentially weighted moving average (EWMA) dispersion control chart. It is suggested to track shift ranges first expected in process dispersion by opting for smoothing constant computation with the help of a function. The shift magnitude assessment is made by an unbiased estimator that determines the smoothing constant value through the proposed function. The enhanced efficiency of the proposed chart can be assessed in terms of smaller run‐length profiles, which are determined through Monte Carlo simulations. The proposed chart is compared with the existing adaptive EWMA dispersion chart, and it turned out to perform substantially efficiently in detecting all kinds of decreasing and increasing process dispersion shift magnitudes. Moreover, a real‐life dataset application is explained in the example section to elaborate on the ease of implementation in the real‐life scenario.
Understanding Within‐ and Cross‐Language Relations Among Language, Preliteracy Skills, and Word Reading in Bilingual Learners: Evidence From the Science of Reading
Authors: Gottardo Alexandra , Chen Xi , Huo Michelle Ru Yun
Published: April 2021

Research has shown that language and literacy skills in a first language (L1) are related to performance in a second language (L2) and that these relations are reciprocal. However, cross‐linguistic skills related to word reading are influenced by numerous factors. These include linguistic factors such as the specific language and literacy skills being examined and the languages being compared. They also include societal/contextual factors, such as the linguistic and educational contexts where learners reside. Specifically, contextual factors include the use of the L1 and L2 in the curriculum (e.g., immersion, dual language, heritage language, available supports), teaching methods, and whether the L1 and L2 are societal languages. Research based on the science of reading for bilinguals has shown that phonological awareness is highly related across languages, whereas other language skills have shown differential levels of relations to reading. Word‐reading skills are also related, but these relations are more complex and are due to linguistic factors such as script and linguistic typology and societal/contextual factors, such as instruction and exposure to each language, which are consistent with various theories. Consideration of a wider range of L1s and L2s and specific contextual/societal factors should be included more systematically. Additionally, learner experiences and specific L1 and L2 variables should be considered in educational decisions.
Feeding Steel Strip Technology in Continuous Casting Process: A Review
Authors: Geng Yi-Feng , Zhao Cheng-Lin , Zang Xi-Min , Wang Yi-Dong , Li Hua-Bing , Li De-Jun , Jiang Zhou-Hua , Zhang Shu-Cai
Published: April 2021

Feeding strip into continuous casting mold is a technique that can reduce the central segregation and increase the equiaxed zone ratio of continuous casting slab. Over the past decades, some steel mills have gradually applied this technique, but it still lacks a comprehensive understanding of the control theory of process parameters. Many parameters joint the influence of the steel strip melting process and strip feeding ratio, deciding the inner quality of the slab eventually. Herein, the mechanism and heat transfer of feeding strip technology are analyzed. Parameter sensitivity studies and feeding strip experiments are summarized and some new conclusions are proposed. Finally, some suggestions for industrial production will give an outlook for future work.
A case of reactive hypoglycemia caused by Kampo medicine
Authors: Yamasaki Genzo
Published: April 2021

Case

Reactive hypoglycemia can occur due to postprandial insulin hypersecretion. However, no Kampo medicine is known to cause this effect. Herein, we describe a case of reactive hypoglycemia that occurred postprandially as an effect of Kampo medicine. A 42‐year‐old woman was admitted because of chest pain. We prescribed saikokaryukotsuboreito, following which the patient's symptoms improved. However, after 9 months, she experienced persistent fatigue after developing a cold. Therefore, we changed the prescription to hochuekkito and keishikaryukotsuboreito. Nevertheless, discomfort in the epigastric region and back pain developed within a few hours after administration of these medications.

Outcome

Results of 75 g oral glucose tolerance test (OGTT) showed excessive insulin secretion, potentially as a result of changing Kampo administration. Therefore, the treatment was changed back to saikokaryukotsuboreito, which resolved the postprandial symptoms. Moreover, the insulin hypersecretion disappeared on subsequent 75 g OGTT.

Conclusion

The promotion of gastric peristaltic function as an effect of Kampo may cause reactive hypoglycemia.
Scales of Change and Diagnostic Contradictions: Shifting Relations Between an Emigrant Community and Its Diaspora
Authors: Trémon Anne-Christine
Published: April 2021

The specific question this chapter addresses is how to account ethnographically for change that unfolds on spatial and temporal scales larger than those of the ethnographic field study without opposing the local site to global forces. My research engages a processual approach which examines the effects of China’s transformations and the creation of the Shenzhen Special Economic Zone on the relationship between the members of a former emigrant community and their diaspora. I propose an analytical distinction between two relational dimensions of scale in which social action can be considered: scale as the scope of social systems or chains of interdependence that extend in space and time and in which actions and interactions take place, and scale as valence, i.e., the desirability of scale defined relative to other scales, generating “scalar projects.” I focus on how contradictions in the collected field materials are telling signs of accelerated change that generate conflicts of scale, and use such “diagnostic contradictions” as a starting point for understanding how people attempt to make sense of rapid change and reconceptualize the valence of local and global scales.
Rescuing Biography from the Nation: Discrete Perspectives on Political Change in Morocco
Authors: Bono Irene
Published: April 2021

Political biographies and the narratives of the nation-state may exert a reciprocal fictional influence: the nation as imagined community is often embodied in the biographies of imaginary actors. Since the 2004 launch of the transitional justice process in Morocco this tendency has led to increased attention for the stories of the victims of the violations committed by the State between 1956 and 1999 as if they were the main witnesses of the political change. In parallel, the protagonists of the nationalist struggle that led to independence from the French protectorate in 1956 have been acknowledged without, apparently, feeling it necessary to hear what they have to say about it. This chapter reflects on theoretical and methodological perspectives that allow the use of biography to explore political change beyond taken-for-granted conceptions of the nation-state and its trajectories of change. Reflecting on the relationship that developed between the author and a single actor called Abk, who wanted to tell his life story, the chapter proposes the writing of biography as a form of archival research and a fieldwork practice for exploring memory. It shows how paying attention to personal ways of conserving memory and remembering enables us to approach politics beyond predefined horizons of change without seeing a priori social configurations as ineluctable givens. Such a perspective, which the author calls “discrete”, suggests considering politics as a phenomenon that is difficult to fit into formal models of explanation, and taking subjectivity, the variability of life paths and contingency as relevant objects of inquiry for understanding political change.
“A Proper House, Not a Barn”: House Biographies and Societal Change in Urban Kyrgyzstan
Authors: Isabaeva Eliza
Published: April 2021

In Kyrgyzstan, scholars disagree about the outcomes of the Tulip Revolution of 2005: while some argue that the revolution has not resulted in noteworthy changes in the country, others see it as the beginning of major political change. To trace the materiality of such change it is necessary to look at the micro-level of a society, as this chapter does by focusing on the house as the unit of analysis for a close study of change. It examines the gradual transformation of dwellings in Ak Jar, an illegal squatter settlement on the northern edge of Kyrgyztan’s capital city Bishkek. The immediate aftermath of the Tulip Revolution saw the emergence of numerous illegal squatter settlements on the outer fringes of the city. Ak Jar, the largest of these, has some 15,000 inhabitants who arrived in Bishkek as internal migrants in search of employment. The dwellings in Ak Jar have changed over the course of time: most began as small mud shacks, and changed when a family generated enough money to improve and expand them. The development of these houses was central for the gradual official recognition of the illegal settlements that emerged in post-revolutionary Kyrgyzstan. House biographies are therefore intrinsically tied to wider developments in Kyrgyz society and throw new light on the ruptures, power struggles, and consolidation of power relations after the Tulip Revolution.
Spatializing Social Change: Artisanal and Small-Scale Gold Mining in Upper Guinea
Authors: Dessertine Anna
Published: April 2021

This chapter proposes a spatial perspective on the analysis of social change in the making via a study of artisanal and small-scale gold-mining sites in Guinea based on twenty-two months of fieldwork between 2011 and 2019 in the region of Upper Guinea, where increasing numbers of inhabitants have been circulating between artisanal and small-scale mining sites to search for gold since the price of gold rose between 2008 and 2012. The chapter starts by discussing artisanal and small-scale mining spaces through the notion of hotspots of transition, insisting on their liminal character. This liminality is analyzed as a spatial framework in which new opportunities emerge regarding gender—women’s adoption of what is considered masculine behavior, for instance—and where instantaneity is more privileged than continuity in some actions, such as those associated with consumption. More generally, it shows how the potential for change in artisanal and small-scale mining spaces is closely linked to their ephemeral nature. The relationship between space and temporality is more explicitly discussed in the second part of the chapter, which explores how the ephemerality of artisanal and small-scale mining spaces has recently been challenged by the Guinean government’s move to control mining mobility and fix mining sites spatially by delimiting legal mining territories. Since 2015–2016, multiple military operations have been conducted to expel miners from land for which the Guinean State has given industrial companies legal permits to prospect for and mine gold. This part of the chapter analyzes the socio-spatial consequences of this situation and shows that perceptions of time and of social change are constructed by the forms that space take.
Cross-National Variation in the Link Between Parental Socio-Economic Status and Union Formation and Dissolution Processes
Authors: Brons M. D.
Published: April 2021

The main objective of this chapter is to understand the link between parental socio-economic status (SES) and union formation and dissolution processes from a cross-national comparative perspective. According to the Second Demographic Transition (SDT) theory, it can be expected that the impact of parental background on these union dynamics differs across societal contexts. Integrated results from prior studies using meta-analytical tools indicate that in many European countries, young adults from advantaged backgrounds delay their first co-residential union and have a higher risk to dissolve their union compared to young adults from disadvantaged backgrounds. The strength of this link between parental SES and union dynamics varies across countries. There is suggestive evidence that the link between parental SES and union dynamics is weakest in North-Western European countries that are most advanced in the SDT. However, next to these SDT-related indicators that focus more on cultural change, institutional country-level indicators, like the extent of educational expansion, and economic country-level indicators, such as the level of economic uncertainty, might also play a role.
Meta-Analysis and Meta-Regression: An Alternative to Multilevel Analysis When the Number of Countries Is Small
Authors: Liefbroer Aart C. , Zoutewelle-Terovan Mioara
Published: April 2021

Hierarchically nested data structures are often analyzed by means of multilevel techniques. A common situation in cross-national comparative research is data on two levels, with information on individuals at level 1 and on countries at level 2. However, when dealing with few level-2 units (e.g. countries), results from multilevel models may be unreliable due to estimation bias (e.g. underestimated standard errors, unreliable country-level variance estimates). This chapter provides a discussion on multilevel modeling inaccuracies when using a small level-2 sample size, as well as a list of available alternative analytic tools for analyzing such data. However, as in practice many of these alternatives remain unfeasible in testing hypotheses central to cross-national comparative research, the aim of this chapter is to propose and illustrate a new technique –the 2-step meta-analytic approach – reliable in the analysis of nested data with few level-2 units. In addition, this method is highly infographic and accessible to the average social scientist (not skilled in advanced simulation techniques).
Modeling the Genesis of Life Courses
Authors: Han Sapphire Yu , Elzinga Cees H.
Published: April 2021

Life course research has been dominated by methods and models that focus on the description of life course patterns and on the causal patterns between agency- and structure-related variables on the one hand and, on the other hand, outcomes in later life. Little attention has been paid to modelling the driving force, the mechanism, that generates the chain of successive events and stages of the life course: the sequences of individual decisions pertaining to all facets of the life course. This paper presents the minimal requirements that models should satisfy in order to be considered as life course generating models. The paper then proposes Hidden Markov Models as one of the main building blocks of life course generating models and discusses a few applications of these models in the domains of family formation, school-to-work transition and their interaction.
Understanding the Mechanisms of Intergenerational Social Inequality in Demographic Behavior
Authors: Hiekel Nicole
Published: April 2021

In this chapter I contrast the economic and cultural perspective of intergenerational transmission processes of social inequality in demographic behavior. I systematically compile the underlying social mechanisms that are scattered across the literature and apply them to the relationships investigated within the CONOPP project. Identifying a predominant focus on the parental resource perspective in the literature linking family background and young adult demographic behavior, I argue in favor of widening the theoretical perspective. Greater theoretical width will enable social scientists to more comprehensively grasp the persistent social stratification of demographic behavior across generations and the role of context in moderating these relationships. I conclude with some suggestions on how future research can further push the boundaries of understanding these relationships.
Product Eco-Design in the Era of Circular Economy: Experiences in the Design of Espresso Coffee Machines
Authors: Favi Claudio , Marconi Marco , Rossi Marta , Cappelletti Federica
Published: April 2021

Product eco-design includes several methodologies aimed at supporting companies in the development of sustainable products. Currently, this theme is assuming an important role in both the academia and industry worlds due to the increasing attention to environmental problems and the need for a transition toward circular economy business/organizational models. In this context, the present paper focuses on the industrial sector of espresso coffee machines manufacturing which has several unexploited potentialities. The analysis of the sector specificity (internal and external contexts), as well as of the product lifecycle allowed to define an eco-design framework to guide companies involved in the design and production of espresso coffee machines. Effective eco-design strategies should include the combined use of specific methods, tools and metrics to manage all the most important lifecycle phases (beginning of life, middle of life, end of life) during the design activities in order to set preventive actions that avoid future potential environmental impacts. Only in this way, the environmental and economic benefits of the circular economy paradigm (e.g. remanufacturing/reuse of selected components) can be practically exploited in real industrial contexts. The presented case studies confirmed that the application of design for disassembly rules positively contributes to increase the product performances during maintenance and end of life, while a re-design oriented to component modularity could be a key strategy to pursue remanufacturing for boilers, a key and expensive component included in espresso coffee machines.
Two-loop leading colour QCD corrections to $$ q\overline{q} $$ → γγg and qg → γγq
Authors: Agarwal Bakul , Buccioni Federico , von Manteuffel Andreas , Tancredi Lorenzo
Published: April 2021

Abstract

We present the leading colour and light fermionic planar two-loop corrections for the production of two photons and a jet in the quark-antiquark and quark-gluon channels. In particular, we compute the interference of the two-loop amplitudes with the corresponding tree level ones, summed over colours and polarisations. Our calculation uses the latest advancements in the algorithms for integration-by-parts reduction and multivariate partial fraction decomposition to produce compact and easy-to-use results. We have implemented our results in an efficient C++ numerical code. We also provide their analytic expressions in Mathematica format.
Mehr Evidenzbasierung in Prävention und Gesundheitsförderung: Kriterien für evidenzbasierte Maßnahmen und notwendige organisationale Rahmenbedingungen und Kapazitäten
Authors: De Bock Freia , Rehfuess Eva
Published: April 2021

Für die Umsetzung des Präventionsgesetzes in einem sich entwickelnden System Prävention und Gesundheitsförderung (PGF) ist die Anforderung der Evidenzbasierung formuliert. Vor diesem Hintergrund stellt sich die Frage, welche Schritte, Prozesse und Vorgehensweisen in diesem System benötigt werden, um der Anforderung zunehmend gerecht zu werden. Dieser Übersichtsartikel diskutiert für Deutschland, wie evidenzbasierte Maßnahmen in der Praxis operationalisiert werden können und welche organisationalen Rahmenbedingungen und Kapazitäten für ein evidenzbasiertes Handeln von AkteurInnen notwendig sind.

Aufbauend auf internationalen wissenschaftlichen Erkenntnissen und dem Memorandum Evidenzbasierte Prävention und Gesundheitsförderung der Bundeszentrale für gesundheitliche Aufklärung (BZgA) wird zunächst das Verständnis von evidenzbasierten Maßnahmen erläutert und im Weiteren werden Elemente zur Umsetzung von mehr Evidenzbasierung skizziert.

Neben der transparenten und einheitlichen Darstellung in Datenbanken und Empfehlungen ist es notwendig, bei EntscheidungsträgerInnen in Praxis und Politik ein gemeinsames Verständnis von evidenzbasierten Interventionen und von Anforderungen für eine Evaluation, die Evidenzbasierung sichert, zu schaffen. Darüber hinaus kann evidenzbasiertes Handeln von EntscheidungsträgerInnen gefördert werden durch Wertschätzung gegenüber Evidenzbasierung in ihren Organisationen, durch Gewährleistung eines regelhaften Zugangs zu Evidenzdatenbanken, durch verbesserte Kompetenzen in Bezug auf Interpretation von Evidenz und durch eine systematische Zusammenarbeit mit der Wissenschaft.

Mehr Evidenzbasierung ist eine Voraussetzung für die nachhaltige Verankerung von PGF als fünfte Säule des Gesundheitssystems.
Vergleich der DRG-Erlöse zwischen Fast- und Slow-Track-Verfahren beim zweizeitigen Prothesenwechsel bei periprothetischen Hüftinfektionen im aG-DRG-System 2020
Authors: Hierl Katja , Rupp Markus , Worlicek Michael , Baumann Florian , Pfeifer Christian , Alt Volker
Published: April 2021

Hintergrund

Die Behandlung periprothetischer Hüftinfektionen ist meist kostenintensiv und gilt im Allgemeinen als nicht kostendeckend für die Kliniken. Bei chronischen Infektionen ist oft ein zweizeitiger Prothesenwechsel indiziert, der als Fast-Track mit kurzem prothesenfreiem Intervall (2–4 Wochen) oder als Slow-Track mit langem prothesenfreiem Intervall (über 4 Wochen) erfolgen kann.

Ziel

Ziel dieser Arbeit war die Erfassung der Erlössituation beider Behandlungsformen im aktuellen aG-DRG-System 2020 unter Berücksichtigung erlösrelevanter Einflussfaktoren.

Methoden

Für Fast-Track und Slow-Track bei zweizeitigem septischem Hüftprothesenwechsel mit Nachweis eines Staphylococcus aureus (MSSA) wurden mittels einer Grouper-Software (3M KODIP Suite) anhand der Diagnosen (ICD-10-GM) und Prozeduren (OPS) Behandlungsfälle simuliert und in DRG eingruppiert. Erlösrelevante Parameter wie Verweildauer (VWD) und Nebendiagnosen (ND) wurden berücksichtigt. Zusätzlich wurden zwei reale Behandlungsfälle mit Fast-Track und Slow-Track miteinander verglichen.

Ergebnisse

Die Gesamterlöse betrugen beim Slow-Track bei einer VWD von 25 Tagen (ohne ND) 27.551 € und bei einer VWD von 42 Tagen (mit ND) 40.699 €. Beim Fast-Track hingegen lag der Gesamterlös bei 23.965 € bei einer VWD von 25 Tagen (ohne ND) und bei 27.283 € bei einer VWD von 42 Tagen (mit ND). Bei den realen Behandlungsfällen zeigte sich ebenfalls eine deutliche Differenz des Gesamterlöses von 12.244 € zugunsten des Slow-Tracks.

Diskussion

Auch im aG-DRG-System 2020 scheint der zweizeitige Hüftprothesenwechsel mit langem Interimsintervall insbesondere bei multimorbiden Patienten aus Krankenhaussicht ökonomisch vorteilhafter zu sein als das Fast-Track-Konzept, wodurch ein finanzielles Hemmnis zur Behandlung solcher Patienten mit kurzem Interimsintervall geschaffen wird.
The wizard and I: How transparent teleoperation and self-description (do not) affect children’s robot perceptions and child-robot relationship formation
Authors: van Straten Caroline L. , Peter Jochen , Kühne Rinaldo , Barco Alex
Published: April 2021

It has been well documented that children perceive robots as social, mental, and moral others. Studies on child-robot interaction may encourage this perception of robots, first, by using a Wizard of Oz (i.e., teleoperation) set-up and, second, by having robots engage in self-description. However, much remains unknown about the effects of transparent teleoperation and self-description on children’s perception of, and relationship formation with a robot. To address this research gap initially, we conducted an experimental study with a 2 × 2 (teleoperation: overt/covert; self-description: yes/no) between-subject design in which 168 children aged 7–10 interacted with a Nao robot once. Transparency about the teleoperation procedure decreased children’s perceptions of the robot’s autonomy and anthropomorphism. Self-description reduced the degree to which children perceived the robot as being similar to themselves. Transparent teleoperation and self-description affected neither children’s perceptions of the robot’s animacy and social presence nor their closeness to and trust in the robot.
Improving AR-powered remote assistance: a new approach aimed to foster operator’s autonomy and optimize the use of skilled resources
Authors: Calandra Davide , Cannavò Alberto , Lamberti Fabrizio
Published: April 2021

Augmented reality (AR) has a number of applications in industry, but remote assistance represents one of the most prominent and widely studied use cases. Notwithstanding, although the set of functionalities supporting the communication between remote experts and on-site operators grew over time, the way in which remote assistance is delivered has not evolved yet to unleash the full potential of AR technology. The expert typically guides the operator step-by-step, and basically uses AR-based hints to visually support voice instructions. With this approach, skilled human resources may go under-utilized, as the time an expert invests in the assistance corresponds to the time needed by the operator to execute the requested operations. The goal of this work is to introduce a new approach to remote assistance that takes advantage of AR functionalities separately proposed in academic works and commercial products to re-organize the guidance workflow, with the aim to increase the operator’s autonomy and, thus, optimize the use of expert’s time. An AR-powered remote assistance platform able to support the devised approach is also presented. By means of a user study, this approach was compared to traditional step-by-step guidance, with the aim to estimate what is the potential of AR that is still unexploited. Results showed that with the new approach it is possible to reduce the time investment for the expert, allowing the operator to autonomously complete the assigned tasks in a time comparable to step-by-step guidance with a negligible need for further support.
8,000 years of climate, vegetation, fire and land-use dynamics in the thermo-mediterranean vegetation belt of northern Sardinia (Italy)
Authors: Pedrotta Tiziana , Gobet Erika , Schwörer Christoph , Beffa Giorgia , Butz Christoph , Henne Paul D. , Morales-Molino César , Pasta Salvatore , van Leeuwen Jacqueline F. N. , Vogel Hendrik , Zwimpfer Elias , Anselmetti Flavio S. , Grosjean Martin , Tinner Willy
Published: April 2021

Knowledge
about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record covering the past ~ 8,000 years from Lago di Baratz, north-west Sardinia. Vegetation and fire history are reconstructed by pollen, spores, macrofossils and charcoal analyses and environmental dynamics by high-resolution element geochemistry together with pigment analyses. During the period 8,100–7,500 cal bp, when seasonality was high and fire and erosion were frequent, Erica arborea and E. scoparia woodlands dominated the coastal landscape. Subsequently, between 7,500 and 5,500 cal bp, seasonality gradually declined and thermo-mediterranean woodlands with Pistacia and Quercus ilex partially replaced Erica communities under diminished incidence of fire. After 5,500 cal bp, evergreen oak forests expanded markedly, erosion declined and lake levels increased, likely in response to increasing (summer) moisture availability. Increased anthropogenic fire disturbance triggered shrubland expansions (e.g. Tamarix and Pistacia) around 5,000–4,500 cal bp. Subsequently around 4,000–3,500 cal bp evergreen oak-olive forests expanded massively when fire activity declined and lake productivity and anoxia reached Holocene maxima. Land-use activities during the past 4,000 years (since the Bronze Age) gradually disrupted coastal forests, but relict stands persisted under rather stable environmental conditions until ca. 200 cal bp, when agricultural activities intensified and Pinus and Eucalyptus were planted to stabilize the sand dunes. Pervasive prehistoric land-use activities since at least the Bronze Age Nuraghi period included the cultivation of Prunus, Olea europaea and Juglans regia after 3,500–3,300 cal bp, and Quercus suber after 2,500 cal bp. We conclude that restoring less flammable native Q. ilex and O. europaea forest communities would markedly reduce fire risk and erodibility compared to recent forest plantations with flammable non-native trees (e.g. Pinus, Eucalyptus) and xerophytic shrubland (e.g. Cistus, Erica).
Micro-perforated panels for noise reduction
Authors: Floss Sebastian , Czwielong Felix , Becker Stefan , Kaltenbacher Manfred
Published: April 2021

Space limitations in duct applications, new industrial and health safety regulations require new absorber configurations. Micro-perforated panels (MPP) as used in micro-perforated absorbers (MPA) allow new sound absorber concepts in the category of metamaterials. In this contribution we investigate MPA designs for the low and mid-to-high frequency range and apply finite element (FE) simulations to precisely design absorber configurations for applications in room acoustics and axial fans. The investigations show that the MPA’s cavity configuration must be customized for the desired frequency range and has significant influence on fan performance when applied in a duct flow setup.
Anterior deltoid muscle tension quantified with shear wave ultrasound elastography correlates with pain level after reverse shoulder arthroplasty
Authors: Schmalzl Jonas , Fenwick Annabel , Reichel Thomas , Schmitz Benedikt , Jordan Martin , Meffert Rainer , Plumhoff Piet , Boehm Dirk , Gilbert Fabian
Published: April 2021

Introduction

Reverse shoulder arthroplasty (RSA) leads to medialization and distalization of the centre of rotation of the shoulder joint resulting in lengthening of the deltoid muscle. Shear wave ultrasound elastography (SWE) is a reliable method for quantifying tissue stiffness. The purpose of this study was to analyse if deltoid muscle tension after RSA correlates with the patients’ pain level. We hypothesized that higher deltoid muscle tension would be associated with increased pain.

Material and methods

Eighteen patients treated with RSA were included. Constant score (CS) and pain level on the visual analogue scale (VAS) were analysed and SWE was performed on both shoulders. All three regions of the deltoid muscle were examined in resting position and under standardized isometric loading.

Results

Average patient age was 76 (range 64–84) years and average follow-up was 15 months (range 4–48). The average CS was 66 points (range 35–89) and the average pain level on the VAS was 1.8 (range 0.5–4.7). SWE revealed statistically significant higher muscle tension in the anterior and middle deltoid muscle region in patients after RSA compared to the contralateral non-operated side. There was a statistically significant correlation between pain level and anterior deltoid muscle tension.

Conclusion

SWE revealed increased tension in the anterior and middle portion of the deltoid muscle after RSA in a clinical setting. Increased tension of the anterior deltoid muscle portion significantly correlated with an increased pain level. SWE is a powerful, cost-effective, quick, dynamic, non-invasive, and radiation-free imaging technique to evaluate tissue elasticity in the shoulder with a wide range of applications.

Level of evidence

Diagnostic study, Level III.
Die Ausbildung von Lehrerinnen und Lehrern als Multiplikatoren für den Wiederbelebungsunterricht an Schulen
Authors: Wingen Sabine , Rott N. , Dirks B. , Greif R. , Papaspyrou H. , Eckstein A. , Lambertz P. , Koch-Schultze R. , Böttiger B. W.
Published: April 2021

Zielsetzung

Die Einführung des Wiederbelebungsunterrichts an Schulen soll die Reanimationsbereitschaft in der Gesellschaft und das Überleben von Menschen mit einem außerklinischen Herz-Kreislauf-Stillstand nachhaltig verbessern. Ziel der vorliegenden Untersuchung war es zu prüfen, wie Lehrkräfte als qualifizierte Multiplikatoren den Wiederbelebungsunterricht in ihren Schulen eigenständig durchführen.

Methodik

Die Uniklinik Köln qualifizierte in Kooperation mit dem Deutschen Rat für Wiederbelebung e. V. in einem speziell entwickelten Kurs Lehrkräfte von weiterführenden Schulen. Von Juli bis November 2019 erfolgte die Evaluation dieses Lehrermultiplikationskonzepts mittels einer webbasierten Umfrage.

Ergebnisse

An der Befragung nahmen 23 von 26 Schulen teil (88 %). Insgesamt haben 96 % (n = 22) der an der Befragung teilnehmenden Schulen den Wiederbelebungsunterricht eingeführt. Es wurden 229 Lehrkräfte ausgebildet, die in dem 2‑jährigen Beobachtungszeitraum 8612 Schüler trainierten. Im Mittel trainierte eine qualifizierte Lehrkraft in ihrer Schule 38 Schüler in Wiederbelebung. Die Multiplikationsfaktoren (Anzahl der trainierten Schülerinnen und Schüler pro Lehrkraft) waren schulindividuell unterschiedlich (Minimum/Maximum: 10/1747). Die schulintern projektverantwortlichen Lehrkräfte gaben an, sich sehr sicher in der eigenständigen Durchführung des Wiederbelebungsunterrichts zu fühlen.

Speziell qualifizierte Lehrkräfte führen den Wiederbelebungsunterricht an ihren Schulen zuverlässig ein. Um noch mehr Schüler mit dem Wiederbelebungstraining zu erreichen, müssen die Multiplikationsfaktoren durch gezielte Unterstützungsangebote weiter erhöht werden.
Olfactory responses of Argentine stem weevil to herbivory and endophyte-colonisation in perennial ryegrass
Authors: Hennessy Louise M. , Popay Alison J. , Glare Travis R. , Finch Sarah C. , Cave Vanessa M. , Rostás Michael
Published: April 2021

Argentine stem weevil adults (ASW,Listronotus bonariensis) feed on the leaves of agricultural grasses and their larvae mine the pseudostem, causing extensive damage that can result in plant death. Plants emit volatiles that serve as signals to host-searching insects and these odours can be altered by both herbivory and fungal endophyte-infection. This study investigated whether ASW adults utilise olfaction to identify their host plants, perennial ryegrass (Lolium perenne), and if conspecific herbivory or the presence ofEpichloë festucaevar.loliifungal endophytes (strain wild-type or AR1) influenced such responses. Results from olfactometer bioassays established that ASW adults were able to utilise their olfactory response to orient towards volatiles released by perennial ryegrass and further, the weevils displayed a preference for plants previously damaged by conspecific weevils. However, there was no evidence that weevils had the ability to distinguish between endophyte-infected and endophyte-free plants using olfaction alone. Using a push–pull extraction technique, thirteen volatile compounds were identified in the blend released by perennial ryegrass. Endophyte and herbivory were found to alter these volatile compounds and quantities emitted by this forage grass. This study suggests that despite observing differences in the plant volatile blend, ASW do not perceive endophyte (wild-type and AR1) using olfaction alone and must rely on other cues, e.g. contact chemoreception or post-ingestional malaise, to detect the presence of a bioactive endophyte in an otherwise acceptable host plant.
Rapid continental spread of a salt-tolerant plant along the European road network
Authors: Fekete R. , Haszonits Gy. , Schmidt D. , Bak H. , Vincze O. , Süveges K. , Molnár V. A.
Published: April 2021

The spread of alien species with the expansion of road networks and increasing traffic is a well-known phenomenon globally. Besides their corridor effects, road maintenance practices, such as the use of de-icing salts during winter facilitate the spread of halophyte (salt tolerant) species along roads. A good example isPlantago coronopus, a mainly coastal halophyte which has started spreading inland from the Atlantic and Mediterranean coastal habitats, recently reaching even Central European countries (e.g. Hungary). Here we studied the spread of this halophyte and tried to identify factors explaining its successful dispersion along roads, while also comparing native and non-native roadside occurrences with regard to altitude of the localities, size of roadside populations and frequency of roadside occurrences. We completed a comprehensive literature review and collected more than 200 reports of occurrence from roadsides spanning a total of 38 years. During systematic sampling the frequency of the species along roads was significantly higher in the Mediterranean (native area), than along Hungarian (non-native area) roads, however the average number of individuals at the sampling localities were very similar, and no significant difference could be detected. Using a germination experiment, we demonstrate that although the species is able to germinate even at high salt concentrations, salt is not required for germination. Indeed salt significantly decreases germination probability of the seeds. The successful spread of the species could most likely be explained by its remarkably high seed production, or some special characteristics (e.g. seed dimorphism) and its ability to adapt to a wide range of environmental conditions. Considering the recent and rapid eastward spread ofP. coronopus, occurrences in other countries where it has not been reported yet can be predicted in coming years.
Genetic programming for feature model synthesis: a replication study
Authors: Vescan Andreea , Pintea Adrian , Linsbauer Lukas , Egyed Alexander
Published: April 2021

Software Product Lines (SPLs) make it possible to configure a single system based on features in order to create many different variants and cater to a wide range of customers with varying requirements. This configuration space is often modeled using Feature Models (FMs). However, in practice, the SPL (and consequently the FM) is often created after a set of variants has already been created manually. Automating the task of reverse engineering a feature model that describes a set of variants makes the process of adopting an SPL easier. The genetic programming pipeline is a good fit for feature models and has been shown to produce good reverse engineering results. In this paper, we replicate the results of such an existing approach with a larger set of feature models and investigate the effects of various genetic programming parameters and operators on the results. The design of our replication experiments employs three perspectives: duplicate the exact conditions using various features models, study the interaction of two parameters of the genetic programming approach, and optimize the values for the population and generation parameters and for the mutation and crossover operators. Results reinforce the previously obtained outcome, the original study being confirmed. The relations between the number of features and number of generations, respectively number of features and size of populations were also investigated and best values based on obtained results are provided. The current study also aimed to optimize various parameters of the genetic programming approach, the interpretation of those experiments discovering concrete values.
Preservice Teachers’ Perception of Plagiarism: A Case from a College of Education
Authors: Romanowski Michael H.
Published: April 2021

Few studies examine plagiarism in a Middle Eastern context, specifically from the perspectives of preservice teachers. As future gatekeepers of academic integrity, preservice teachers need to understand plagiarism. This study surveyed 128 female preservice teachers in one university in the Gulf Cooperation Council (GCC) countries. The survey explores preservice teachers regarding their understandings and reasons for academic plagiarism and their responses to particular scenarios. Findings indicate that preservice teachers have a thorough comprehension of plagiarism and suggest a lack of knowledge of citing sources, weak writing skills, a lack of time, and not knowing the research process as reasons for plagiarism. Informants' responses to six scenarios are presented to illustrate their perspectives further. Discussion addresses language and cultural issues to contextualize the study.
The Co-development of Friends’ Delinquency with Adolescents’ Delinquency and Short-term Mindsets: The Moderating Role of Co-Offending
Authors: Defoe Ivy N. , van Gelder Jean-Louis , Ribeaud Denis , Eisner Manuel
Published: April 2021

The companions in crime hypothesis suggests that co-offending moderates the link between peer delinquency and adolescent delinquency. However, this hypothesis has rarely been investigated longitudinally. Hence, this study investigated the co-development of friends’ delinquency and adolescents’ delinquency, as well as the co-development of friends’ delinquency and short-term mindsets (impulsivity and lack of school future orientation). Whether this co-development is stronger when adolescents engage in co-offending was also investigated. Three data waves with two year lags from an ethnically-diverse adolescent sample (at wave 1: N = 1365; 48.6% female; Mage = 13.67; age range = 12.33–15.09 years) in Switzerland were used. The results from parallel process latent growth modeling showed that the co-development between friends’ delinquency and adolescents’ delinquency was stronger when adolescents engaged in co-offending. Thus co-offending likely provides direct access to a setting in which adolescents continue to model the delinquency they learned with their peers.
Human cardiac fibroblasts produce pro-inflammatory cytokines upon TLRs and RLRs stimulation
Authors: Li Zhe , Nguyen Tuan T. , Valaperti Alan
Published: April 2021

Heart inflammation is one of the major causes of heart damage that leads to dilated cardiomyopathy and often progresses to end-stage heart failure. In the present study, we aimed to assess whether human cardiac cells could release immune mediators upon stimulation of Toll-like receptors (TLRs) and Retinoic acid-inducible gene (RIG)-I-like receptors (RLRs).

Commercially available human cardiac fibroblasts and an immortalized human cardiomyocyte cell line were stimulated in vitro with TLR2, TLR3, and TLR4 agonists. In addition, cytosolic RLRs were activated in cardiac cells after transfection of polyinosinic-polycytidylic acid (PolyIC). Upon stimulation of TLR3, TLR4, MDA5, and RIG-I, but not upon stimulation of TLR2, human cardiac fibroblasts produced high amounts of the pro-inflammatory cytokines IL-6 and IL-8. On the contrary, the immortalized human cardiomyocyte cell line was unresponsive to the tested TLRs agonists. Upon RLRs stimulation, cardiac fibroblasts, and to a lesser extent the cardiomyocyte cell line, induced anti-viral IFN-β expression.

These data demonstrate that human cardiac fibroblasts and an immortalized human cardiomyocyte cell line differently respond to various TLRs and RLRs ligands. In particular, human cardiac fibroblasts were able to induce pro-inflammatory and anti-viral cytokines on their own. These aspects will contribute to better understand the immunological function of the different cell populations that make up the cardiac tissue.