bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study on the Factors Affect the Technology Satisfaction on AI Based Self-service Technology Service Failure in Hotel
Authors: QianTing Lu , Chung Hee Chung , Chung Namho
Published: January 2021

The advancement of technology following the Fourth Industrial Revolution and the surge in demand for untact services caused by COVID-19 will gradually expand the scope of service automation through artificial intelligence (AI) technologies. In practice, numerous hotels are adopting AI-based service technologies, but it is still in its early stage to provide guidelines for the overall service strategy for this technology. Therefore, this study conducted a study on the failure of AI based self-service technologies (SSTs), service recovery, and the psychological expectations of customers’ SST. An online survey was conducted on respondents who had experience using AI based SSTs, and a total of 370 responses were used for analysis. As a result of structural model analysis through AMOS, it was found that adequate service recovery and low expectations for SSTs were satisfied with SSTs and hotels as a result, even if service failures were experienced. These findings provide specific practical guidelines for many hotels promoting AI-based service automation.
Gen Z and Esports: Digitizing the Live Event Brand
Authors: de Freitas Rebecca
Published: January 2021

As digitization converges with globalization, industries across the world establish new standards, platforms and audience engagement methods to delight consumers adjusting to CV19’s virtual space. Within the Tourism and Hospitality industry, gamification provides the events and meetings sector an opportunity to implement hybrid events at a level unseen before. Esports is the newest standard of gamification for hybrid, both live and virtual, events. However, within this new standard, there is a large knowledge gap among event organizers of how to execute an esport experience and why esports dominance is necessary to incorporate into hospitality and tourism models. Through understanding esports’ majority consumer, Gen Z, and accurately reflecting esports culture, event organizers will assist the tourism economy through prosperous esport events.
Coworking and Coliving: The Attraction for Digital Nomad Tourists
Authors: Chevtaeva Ekaterina
Published: January 2021

The study facilitates digital nomadism for tourism research and recognizes a unique product offer on the market: the combined coworking and coliving space in compelling or exotic destinations. The aim of the study is to explore the experience of coworking and coliving by digital nomads and identify valuable elements. Qualitative interview data are used to analyse combined coworking and coliving space environments from the perspective of digital nomad tourists. A better understanding of digital nomad preferences may help destinations and business owners to attract digital nomads during and after the pandemic. The study’s findings, perceived advantages and disadvantages of coworking and coliving spaces, may serve as a guideline for targeting digital nomads.
Robo-Tipping: Are Customers Game?
Authors: Cain Lisa , Berezina Katerina
Published: January 2021

This study sought to investigate customer attitudes towards tipping robotic employees in bars. A convenience sample of participants who were 21 years of age or older and who had patronized a bar was recruited using Amazon’s Mechanical Turk platform. Of the 102 usable responses, only 15 participants had experienced robotic bartender service. Only 11 individuals (10.8%) in total said they would tip a robot; 10 of those were respondents who had acutally experienced robotic bartenders, representing 67% of that subsample. Participants listed efficiency and required maintenance as reasons for giving a tip to a robotic bartender. Out of 91 respondents who initially declined to tip a robotic bartender, 38 study participants (41.8%) agreed to tip if they knew that the collected funds would go to human employees. However, in the same group of respondents, only 14 (15.4%) agreed to tip in the scenario when tipping would serve as a learning experience for a robot to understand customer preferences. The rationale for not tipping included such reasoning as robots are machines that do not need extra income and cannot appreciate the gesture. This study suggests that explaining how the collected funds will be used may positively impact consumer intentions to tip a robotic bartender. This extra revenue may help offset the cost of the robot, and subsequently lower the prices of the drinks served at a robotic bar, thus making the product more affordable for a wider audience.
The Implicit and Explicit Motivations of Tourist Behaviour in Sharing Travel Photographs on Instagram: A Path and Cluster Analysis
Authors: Daxböck Jennifer , Dulbecco Maria Laura , Kursite Sintija , Nilsen Tommy Kristoffer , Rus Andrada Diana , Yu Joanne , Egger Roman
Published: January 2021

Instagram has been an emerging platform for tourists to share their experiences and connect with other users in the multiphasic travel stages. Despite the huge number of photographs shared on Instagram on a daily basis, it remains ambiguous regarding the underlying motives of tourists’ posting behaviour. Thus, this study aims to conceptualise a framework based on the internal and external triggers of sharing travel photographs through a mix methods design involving diary studies and questionnaires. By conducting a path analysis, this study presents and validates a theoretical model including various motivational factors; namely enjoyment, self-esteem, recognition, interests, social norms, goals, social ties, social status and prestige, self-efficiency, outcome expectations and memorabilia. Meanwhile, this research clusters young techsavvy tourists into four distinct segments based on their behaviour of using Instagram while traveling. By bridging motivational theories, social psychology, and social media in the context of tourism, this research extends literature related to user-generated content and Instagram. Practically, this research allows marketers to optimise the effectiveness of marketing strategies based on the characteristics of tourists and their behaviour on social media platforms.
Do Tourists from Different Countries Interpret Travel Experience with the Same Feeling? Sentiment Analysis of TripAdvisor Reviews
Authors: Wang Luyu , Kirilenko Andrei P.
Published: January 2021

National parks attract millions of tourists to enjoy the beauty of nature. The opinions and feelings expressed by tourists in their reviews through social media significantly impact other visitors’ tourism-related decisions. Notably, tourists from different countries visiting the same park may express different sentiments and post different experiences. It is not clear if those differences could be attributed to the differences in sentiment analysis software for different languages, or they reflect existing variability in culturally defined tourists’ sentiments. To address this question, this study analyzed 27,177 TripAdvisor Grand Canyon, US reviews from visitors arriving from ten different countries with the goal of identification of sentiment differences. We found that while all reviews tend to be positive, there are significant regional differences with European and Japanese tourists routinely expressing lesser satisfaction from their visit. We also found differences in the sentiment expressed in different regions of the same country, such as the north and south of Italy. Overall, we suggest that social media reflects the real differences in the sentiment of visitors coming from different origins.
In-room Voice-Based AI Digital Assistants Transforming On-Site Hotel Services and Guests’ Experiences
Authors: Buhalis Dimitrios , Moldavska Iuliia
Published: January 2021

Voice-based artificial intelligence (AI) devices transform human-computer bidirectional interactions with new touchpoints. Despite the recent release of purpose-developed in-room voice assistants for hotels, they have not been widely deployed by hospitality companies. There is limited research on the phenomenon of voice-based digital assistants and a research gap in their adoption by hotels for automating workflows and enhancing guests’ experiences. This study analysed the role of voice devices for mediating interactions between hotels and guests from both the hospitality technology providers’ and guests’ perspectives. This was done by the means of inductive qualitative research using 28 semi-structured interviews. The findings revealed that benefits associated with the application of voice-based digital assistants in hospitality outweigh the drawbacks for both hotels and guests. The paper proposes a model which illustrates the essence of speech-based interactions between hotels and guests via voice assistants. This concept contributes to human-computer interactions in the hotel industry.
Information Characteristics on Instagram and Viewer Behavior
Authors: Kim Eunmi , Park Jae Eun (Francesca) , Kim Jin-Young , Koo Chulmo
Published: January 2021

Image-based social media such as Instagram is actively used as a tourism marketing channel that provides information regarding tourist destinations. Recognizing the importance of viewers’ responses, this study investigated the relationship between viewers’ responsive behavior and the characteristics of texts and images posted on Instagram. The results of multiple regression analysis showed that certain emotional expressions in hashtags and images that include people are positively associated with the number of likes and comments. This study provides insights into social media utilization strategies and post-marketing strategies that are helpful for DMO (Destination Marketing Organization).
Smart Tourism Cities’ Competitiveness Index: A Conceptual Model
Authors: Chung Namho , Lee Hyunae , Ham Juyeon , Koo Chulmo
Published: January 2021

As smart tourism cities are becoming a blur boundary between residents and tourists at a spatial place (e.g., urban city or destination), innovation and technologies should be integrated with tourism applications and urban infrastructure. The idea of smart tourism cities is generated as incorporating tourism business or tourism context into everyday life, opening up opportunities in daily life and travel. We need to explore a possible concept of smart tourism cities and how urban cities can play a role of the duality emphasizing on the blurring boundaries and allowing both residents and travelers to co-create the value of the urban cities’ competitiveness name as ‘smart tourism cities.’ This study aims to develop a competitiveness evaluation index for sustaining urban cities through tourism.
Virtual Reality as a Travel Substitution Tool During COVID-19
Authors: Sarkady Daniel , Neuburger Larissa , Egger Roman
Published: January 2021

The pandemic outbreak of COVID-19 in 2020 has profoundly affected the global leisure and tourism industry, with international travel bans affecting over 90% of the world’s population. Widespread restrictions on community mobility have resulted in a projected decline of international tourism arrivals up to 30%. The rapid development of Virtual Reality (VR) and its effectiveness in the simulation of real-life experiences provides an opportunity for virtual holiday making especially when actual travel is not possible. Based on a quantitative study with 193 participants, the role of VR as a substitute for physical travel during the pandemic outbreak of COVID-19 was examined, more specifically by looking at the relationship between perceived risk to travel and technological acceptance of VR. The findings suggest that tourists use VR as a travel substitute during and even after a pandemic. However, perceived risk does not play a significant role when it comes to using VR.
Cowpea Innovation Platform Interventions and Achievements in TL III Project in Burkina Faso
Authors: Joseph Batieno Benoit , Leandre Poda Saadon , Silamana Barry , Evelyne Compaore , Hamadou Zongo , Hamadou Sidibe , Karidiatou Gnankambary , Adelaide Sanou Ouedraogo , James Neya B.
Published: January 2021

In June 2015, four multi-stakeholder platforms (Sanguie, Zondoma, Soum, and Association Yiye) were established in different regions of Burkina Faso to promote agricultural activities. By 2018, more than 200 farmers had already been trained on different aspects of the cowpea value chain including grain production, storage, and food processing skills. The platforms played a key role in the dissemination of new cowpea varieties through demonstrations, field days, the mass media, and social media. About 160 demonstrations were established by the members of the platforms every year from 2015 to 2018. Each platform was supported to produce 10 ha of certified seeds making a total of 40 ha each year and 160 ha during the four-year period. Due to the demand for foundation seeds that was increasing year after year in Burkina Faso and the inability of INERA to produce enough seeds, the most successful platform members were contracted by the INERA Seed Unit to produce foundation seeds in order to meet the high demand in the country for certified seed production. Although there are no official statistics about certified seeds produced in Burkina Faso in terms of demand, recent happenings have shown their increased production. For instance, in 2018 about 1000 tons of certified seeds were produced compared to previous years which had less than 700 tons.
Impact Assessment of Developing Sustainable and Impact-Oriented Groundnut Seed System Under the Tropical Legumes (III) Project in Northern Nigeria
Authors: Mohammed S. G. , Halliru M. , Jibrin J. M. , Kapran I. , Ajeigbe H. A.
Published: January 2021

Tropical Legumes III project as a development intervention focused on enhancing smallholder farmers’ access to seeds of improved groundnut varieties using multi-stakeholder platforms. Open Data Kit was used to collect information from the platform members using structured questionnaires and focus group discussions (FGDs). Descriptive statistics and adoption score were used to analyze the data. Selection of appropriate project location, reliable beneficiaries, timely supply of seeds, and training on good agronomic practices (GAPs) and effective supervision on production were the major thrusts of the TL III project. The results indicated that the IP members accrued additional income ranging from $214 to $453 per hectare for wet season. The same increase in beneficiaries’ income was reported per hectare for dry season from $193 to $823, respectively; all due to the TL III intervention. The results further indicated increasing access by farmers to services (e.g., improved seeds, extension, credit facilities, market, etc.) and enhanced productivity (farm size, pod and haulm yields). Findings further revealed an average increased market price of 21.5% and 18% for dry and wet season groundnut production, respectively. There was high adoption score (78%) of improved seeds and other GAPs. The study recommends the need to replicate similar interventions in other areas. Continued capacity building on GAPs and improved business management skills to Extension Agents and farmer groups will sustain the successes achieved by the TL III project.
Organized Farmers Towards Chickpea Seed Self-Sufficiency in Bundelkhand Region of India
Authors: Sah Uma , Chaturvedi S. K. , Dixit G. P. , Singh N. P. , Gaur P.
Published: January 2021

Smallholder partner farmers under TL-III project were organized into four registered Farmers’ Seed Societies for addressing the challenge of constrained availability of quality seed of improved chickpea varieties in Bundelkhand region of Uttar Pradesh state, India. These seed societies formed in Banda, Hamirpur and Chitrakoot districts contributed towards strengthening the formal seed system of chickpea by contributing 21.8 tons of chickpea seed (FS/TL) of recommended varieties (kabuli: Ujjawal, Shubhra; Desi: JG 14, JG 16 and JAKI 9218) and marketed it to institutionalized seed chains. More than 1500 partner farmers directly received the improved seed through farmers ‘seed societies while 1788 non-partner farmers received it indirectly through social networks. The interventions boosted chickpea productivity from 0.78 to 1.19 t/ha in the project villages. The efforts of the farmers’ societies to strengthen the informal seed system through farmer-to-farmer horizontal diffusion resulted in area enhancement under the introduced chickpea varieties up to 68% in the project villages while putting in place a system for supply of improved chickpea seed which can be replicated in other districts in India.
Positive geometry, local triangulations, and the dual of the Amplituhedron
Authors: Herrmann Enrico , Langer Cameron , Trnka Jaroslav , Zheng Minshan
Published: January 2021

Abstract

We initiate the systematic study of local positive spaces which arise in the context of the Amplituhedron construction for scattering amplitudes in planar maximally supersymmetric Yang-Mills theory. We show that all local positive spaces relevant for one-loop MHV amplitudes are characterized by certain sign-flip conditions and are associated with surprisingly simple logarithmic forms. In the maximal sign-flip case they are finite one-loop octagons. Particular combinations of sign-flip spaces can be glued into new local positive geometries. These correspond to local pentagon integrands that appear in the local expansion of the MHV one-loop amplitude. We show that, geometrically, these pentagons do not triangulate the original Amplituhedron space but rather its twin “Amplituhedron-Prime”. This new geometry has the same boundary structure as the Amplituhedron (and therefore the same logarithmic form) but differs in the bulk as a geometric space. On certain two-dimensional boundaries, where the Amplituhedron geometry reduces to a polygon, we check that both spaces map to the same dual polygon. Interestingly, we find that the pentagons internally triangulate that dual space. This gives a direct evidence that the chiral pentagons are natural building blocks for a yet-to-be discovered dual Amplituhedron.
On the number of principal ideals in d-tonal partition monoids
Authors: Ahmed Chwas , Martin Paul , Mazorchuk Volodymyr
Published: January 2021

For a positive integer d, a non-negative integer n and a non-negative integer $$h\le n$$

h
≤
n

, we study the number $$C_{n}^{(d)}$$

C

n

(
d
)

of principal ideals; and the number $$C_{n,h}^{(d)}$$

C

n
,
h

(
d
)

of principal ideals generated by an element of rank h, in the d-tonal partition monoid on n elements. We compute closed forms for the first family, as partial cumulative sums of known sequences. The second gives an infinite family of new integral sequences. We discuss their connections to certain integral lattices as well as to combinatorics of partitions.
Zirkulärer Weichteildefekt nach prolongiertem Belassen eines strangulierenden Kompressionsstrumpfes
Authors: Mirtschink Sophia Juliane , Manke Elisabeth , Schneiders Wolfgang
Published: January 2021

Das prolongierte Belassen des Thrombosestrumpfes kann zu tiefgradigen Haut‑/Weichteildefekten führen. In dem konkreten Fall kam es zu einer zirkulären Nekrose mit freiliegender Sehne des M. tibialis anterior und der Achillessehne. Die Defektdeckung mittels M.-peronaeus-brevis-Lappen führte zu einer adäquaten Bedeckung der Achillessehne. Dieser Lappen stellt, insbesondere bei multimorbiden Patienten, aufgrund der kurzen Operations- und Narkosezeit eine gute Möglichkeit zur Defektdeckung am Unterschenkel dar. Dieser Fall sensibilisiert für die Wichtigkeit einer adäquaten Patientenschulung vor Beginn einer Kompressionstherapie.
Concentration–QTc analysis of quizartinib in patients with relapsed/refractory acute myeloid leukemia
Authors: Kang Dongwoo , Ludwig Elizabeth , Jaworowicz David , Huang Hannah , Fiedler-Kelly Jill , Cortes Jorge , Ganguly Siddhartha , Khaled Samer , Krämer Alwin , Levis Mark , Martinelli Giovanni , Perl Alexander , Russell Nigel , Abutarif Malaz , Choi Youngsook , Yin Ophelia
Published: January 2021

Purpose

This analysis evaluated the relationship between concentrations of quizartinib and its active metabolite AC886 and QT interval corrected using Fridericia’s formula (QTcF) in patients with relapsed/refractory acute myeloid leukemia (AML) treated in the phase 3 QuANTUM-R study (NCT02039726).

Methods

The analysis dataset included 226 patients with AML. Quizartinib dihydrochloride was administered as daily doses of 20, 30, and 60 mg. Nonlinear mixed-effects modeling was performed using observed quizartinib and AC886 concentrations and time-matched mean electrocardiogram measurements.

Results

Observed QTcF increased with quizartinib and AC886 concentrations; the relationship was best described by a nonlinear maximum effect (Emax) model. The predicted mean increase in QTcF at the maximum concentration of quizartinib and AC886 associated with 60 mg/day was 21.1 ms (90% CI, 18.3–23.6 ms). Age, body weight, sex, race, baseline QTcF, QT-prolonging drug use, hypomagnesemia, and hypocalcemia were not significant predictors of QTcF. Hypokalemia (serum potassium < 3.5 mmol/L) was a statistically significant covariate affecting baseline QTcF, but no differences in ∆QTcF (change in QTcF from baseline) were predicted between patients with versus without hypokalemia at the same quizartinib concentration. The use of concomitant QT-prolonging drugs did not increase QTcF further.

Conclusion

QTcF increase was dependent on quizartinib and AC886 concentrations, but patient factors, including sex and age, did not affect the concentration–QTcF relationship. Because concomitant strong cytochrome P450 3A (CYP3A) inhibitor use significantly increases quizartinib concentration, these results support the clinical recommendation of quizartinib dose reduction in patients concurrently receiving a strong CYP3A inhibitor.

Clinical Trial Registration

NCT02039726 (registered January 20, 2014).
Exosomes induce endolysosomal permeabilization as a gateway by which exosomal tau seeds escape into the cytosol
Authors: Polanco Juan Carlos , Hand Gabriel Rhys , Briner Adam , Li Chuanzhou , Götz Jürgen
Published: January 2021

The microtubule-associated protein tau has a critical role in Alzheimer’s disease and other tauopathies. A proposed pathomechanism in the progression of tauopathies is the trans-synaptic spreading of tau seeds, with a role for exosomes which are secretory nanovesicles generated by late endosomes. Our previous work demonstrated that brain-derived exosomes isolated from tau transgenic rTg4510 mice encapsulate tau seeds with the ability to induce tau aggregation in recipient cells. We had also shown that exosomes can hijack the endosomal pathway to spread through interconnected neurons. Here, we reveal how tau seeds contained within internalized exosomes exploit mechanisms of lysosomal degradation to escape the endosome and induce tau aggregation in the cytosol of HEK293T-derived ‘tau biosensor cells’. We found that the majority of the exosome-containing endosomes fused with lysosomes to form endolysosomes. Exosomes induced their permeabilization, irrespective of the presence of tau seeds, or whether the exosomal preparations originated from mouse brains or HEK293T cells. We also found that permeabilization is a conserved mechanism, operating in both non-neuronal tau biosensor cells and primary neurons. However, permeabilization of endolysosomes only occurred in a small fraction of cells, which supports the notion that permeabilization occurs by a thresholded mechanism. Interestingly, tau aggregation was only induced in cells that exhibited permeabilization, presenting this as an escape route of exosomal tau seeds into the cytosol. Overexpression of RAB7, which is required for the formation of endolysosomes, strongly increased tau aggregation. Conversely, inhibition of lysosomal function with alkalinizing agents, or by knocking-down RAB7, decreased tau aggregation. Together, we conclude that the enzymatic activities of lysosomes permeabilize exosomal and endosomal membranes, thereby facilitating access of exosomal tau seeds to cytosolic tau to induce its aggregation. Our data underscore the importance of endosomal membrane integrity in mechanisms of cellular invasion by misfolded proteins that are resistant to lysosomal degradation.
Impact of tourniquet during knee arthroplasty: a bayesian network meta-analysis of peri-operative outcomes
Authors: Migliorini Filippo , Maffulli Nicola , Aretini Paolo , Trivellas Andromahi , Tingart Markus , Eschweiler Jörg , Baroncini Alice
Published: January 2021

Introduction

The role of tourniquet during knee arthroplasty is controversial. The present study compares various tourniquet protocols using a Bayesian network meta-analysis of peri-operative data.

Material and methods

The present study was conducted in accordance with the PRISMA extension statement for reporting systematic reviews incorporating network meta-analyses of health interventions. The literature search was conducted in September 2020. All clinical trials investigating the role of tourniquet in knee arthroplasty were considered for inclusion. Methodological quality was assessed using Review Manager 5.3. A Bayesian hierarchical random-effects model analysis was used in all comparisons.

Results

Ultimately, pooled data from 68 studies (7413 procedures) were analysed. Significant inconsistency was found in the data relating to total estimated blood lost; no assumption could be made on this outcome. Full-time tourniquet resulted in the shortest surgical duration and lowest intra-operative blood lost, in both cases followed by incision-to-suture. The incision-to-suture protocol achieved the smallest drop in haemoglobin during the first 72 h post-operatively and the lowest rate of blood transfusion, both followed by full-time tourniquet. Hospitalisation was shortest in the absence (no-tourniquet) group, followed by the cementation-to-end group.

Conclusion

For knee arthroplasty, longer tourniquet use is associated with the shorter duration of surgery, lower intra-operative blood lost, lower drops in haemoglobin and fewer transfusion units. The shortest average hospitalisation was associated with no tourniquet use.
Einstein on involutions in projective geometry
Authors: Sauer Tilman , Schütz Tobias
Published: January 2021

We discuss Einstein’s knowledge of projective geometry. We show that two pages of Einstein’s Scratch Notebook from around 1912 with geometrical sketches can directly be associated with similar sketches in manuscript pages dating from his Princeton years. By this correspondence, we show that the sketches are all related to a common theme, the discussion of involution in a projective geometry setting with particular emphasis on the infinite point. We offer a conjecture as to the probable purpose of these geometric considerations.
CPSDebug: Automatic failure explanation in CPS models
Authors: Bartocci Ezio , Manjunath Niveditha , Mariani Leonardo , Mateis Cristinel , Ničković Dejan
Published: January 2021

Debugging cyber-physical system (CPS) models is a cumbersome and costly activity. CPS models combine continuous and discrete dynamics—a fault in a physical component manifests itself in a very different way than a fault in a state machine. Furthermore, faults can propagate both in time and space before they can be detected at the observable interface of the model. As a consequence, explaining the reason of an observed failure is challenging and often requires domain-specific knowledge. In this paper, we propose approach, a novel CPSDebug that combines testing, specification mining, and failure analysis, to automatically explain failures in Simulink/Stateflow models. In particular, we address the hybrid nature of CPS models by using different methods to infer properties from continuous and discrete state variables of the model. We evaluate CPSDebug on two case studies, involving two main scenarios and several classes of faults, demonstrating the potential value of our approach.
Untersuchungen zum wirksamen Reibdurchmesser in der Auflage für Verschraubungen mit Keilsicherungsscheiben aus Kohlenstoffstahl
Authors: Denkert Christian , Ganschow Jörg , Henkel Knuth-Michael
Published: January 2021

Im Maschinenbau sowie im Stahl- und Metallbau gehört das Verschrauben zu den am weitesten verbreiteten Verfahren, um einzelne Bauteile miteinander zu fügen. Einerseits gewährleisten Verschraubungen eine flexible Montage und Demontage auch abseits von Fertigungs- und Werkstattkapazitäten auf Baustellen oder im „Feld“. Andererseits sind große Konstruktionen in zerlegbaren Baugruppen einfacher transportabel, was einen entscheidenden logistischen Vorteil geschraubter Verbindungen darstellt. Verglichen mit Schweißkonstruktionen entfällt beim Schrauben zudem eine Wärmeeinbringung in die Bauteile. Veränderungen des Werkstoffgefüges, Bauteilverzug sowie die Vor- und Nacharbeiten am Korrosionsschutz müssen bei Schraubenverbindungen nicht in besonderem Ausmaß berücksichtigt werden. Auch das Fügen unterschiedlicher Werkstoffe gelingt mit Schraubenverbindungen vorteilhaft. Neben den Vorteilen müssen jedoch auch die inhärenten Nachteile erwähnt werden. Verschraubungen sind im Allgemeinen auf eine Vorspannkraft angewiesen. Als nachteilig ist anzusehen, dass die Vorspannkraft hierbei stark vom gewählten Montageverfahren abhängt und u. U. starke Streuungen aufweist. Um ein selbsttätiges Losdrehen zu unterbinden, werden bisweilen Keilsicherungsscheiben als wirksame Sicherungsmaßnahme für Verschraubungen eingesetzt. Der vorliegende Beitrag stellt Ergebnisse aus Drehmoment/Vorspannkraft-Versuchen mit Keilsicherungsscheiben vor. Hierfür wird der Auflagereibdurchmesser unter Berücksichtigung der Auflagereibungsmomente in Abhängigkeit der Montagevorspannkraft experimentell bestimmt und ausgewertet.
Correction to: The clinical usage of liposomal amphotericin B in patients receiving renal replacement therapy in Japan: a nationwide observational study
Authors: Obata Yoko , Takazono Takahiro , Tashiro Masato , Ota Yuki , Wakamura Tomotaro , Takahashi Akinori , Sato Kumiko , Miyazaki Taiga , Nishino Tomoya , Izumikawa Koichi
Published: January 2021

The original article can be found online.
Systemic Explanations of Scientific Misconduct: Provoked by Spectacular Cases of Norm Violation?
Authors: Huistra Pieter , Paul Herman
Published: January 2021

In the past two decades, individual explanations of scientific misconduct (‘bad apples’) have increasingly given way to systemic explanations (‘bad systems’). Where did this interest in systemic factors (publication pressure, competition for research funding) come from? Given that research ethicists often present their interventions as responses to scientific misconduct, this article tests the hypothesis that these systemic explanations were triggered by high-visibility cases of scientific norm violation. It does so by examining why Dutch scientists in 2011 explained Diederik Stapel’s grand-scale data fabrication largely in systemic terms, whereas only fifteen years earlier, in the René Diekstra affair (1996), such explanations had been close to absent. Drawing on a wealth of historical sources, the article suggests that cases like Stapel’s as such do not explain why early 21st-century commentators exchanged individual explanations for systemic ones. Only against the background of an existing discourse of criticism of the science system, developed in the 1990s and 2000s in response to rapidly increasing competition for research funding, could the Stapel affair achieve notoriety as an example of how systemic factors provoke bad conduct.
Effects of weeding and fertilization on soil biology and biochemical processes and tree growth in a mixed stand of Dalbergia odorifera and Santalum album
Authors: Zhang Peng , Li Xiaofei , Xue Shiyu , Cui Zhiyi , Xu Daping , Yang Zengjiang
Published: January 2021

In southern China, the eucalyptus plantation industry has been severely restricted by government policy over concerns on negative environmental impacts. In its place, large-scale plantations of high-value tropical tree species such as nitrogen-fixing Dalbergia odorifera and hemiparasite Santalum album have been widely cultivated including in mixed-species plantations. However, despite their poor growth, little information is available on suitable silvicultural practices of these plantations. Therefore, we subjected an 8-year-old mixed stand of D. odorifera and S. album to weeding, fertilization, weeding + fertilization, or no (CK) treatments and measured soil microbial biomass, respiration, nutrients, nitrogen mineralization and leaching and tree growth and litter production. Weeding and fertilization decreased microbial biomass but increased soil respiration, inhibited mineralization, had not effect on leaching of soil nitrogen, and improved the nutrient status of plantation soil. All practices improved the growth of D. odorifera. In the mixed plantation, fertilization increased litter production and nutrient content, but weeding and weeding + fertilization decreased growth of S. album and litter production in mixed plantation because weeding decreased the number of S. album haustoria in underground plant roots. In conclusion, fertilization is recommended; however, weeding-related practices are inappropriate for D. odorifera and S. album mixed plantations. These conclusions have important implications for managing other parasite or mixed-species plantations.
Compensatory and overcompensatory dynamics in prey–predator systems exposed to harvest
Authors: Wikan Arild , Kristensen Ørjan
Published: January 2021

Density dependent prey–predator systems under the impact of harvest are considered. The recruitment functions for both the prey and predator belong to the Deriso–Schnute family which allow us to study how the dynamical behaviour of both populations changes when compensatory density dependence turns overcompensatory. Depending on the degree of overcompensation, we show in the case of no harvest that an increase of the fecundity of the prey always acts in a destabilizing fashion. If the degree of overcompensation becomes sufficiently large, such an increase can lead to large amplitude chaotic oscillations of the prey, which actually may drive the predator population to extinction. The impact of harvest also depends on the degree of overcompensatory density dependence. If only the prey is the target population, increased harvest in general seems to stabilize the dynamics. On the other hand, harvesting only the predator may in some cases tend to stabilize dynamics, but there are also parameter regions where this turns out to be a strong destabilizing effect.
A Systematic Review of Palpitations Prevalence by Menopausal Status
Authors: Carpenter Janet S. , Sheng Ying , Elomba Charles D. , Alwine Jennifer S. , Yue Min , Pike Caitlin A. , Chen Chen X. , Tisdale James E.
Published: January 2021

Purpose of the Review

The purpose was to systematically review evidence on the prevalence of palpitations by menopausal stage. Palpitations are a feeling of missed, irregular, or exaggerated heart beats.

Recent Findings

Carefully delineated search, screening, and data extraction strategies resulted in five articles for review. Articles offered cross-sectional findings from menopausal symptom surveys from five countries between 1974 and 2011 with clinic- and community-based samples of premenopausal, perimenopausal, and postmenopausal women. Reported studies were good (n = 2) to fair (n = 3) quality with low (n = 2) to moderate (n = 3) bias. Menopausal palpitations were not the focus of any study but were assessed as a single item of heart racing, pounding, or discomfort over the past 2 weeks, month, or year. Palpitations prevalence rates by menopausal stage were 3.7 to 40.2% premenopausal, 20.1 to 40.2% perimenopausal, and 15.7 to 54.1% postmenopausal. Three of five articles showed that compared with premenopausal and postmenopausal women, palpitation prevalence was significantly higher among perimenopausal and surgically postmenopausal women.

Good-quality evidence on palpitation prevalence by menopausal stage is limited but suggests that physiological changes of menopause may play a role in this symptom. Measurement varied, suggesting a need to standardize the assessment of menopausal palpitations. The review findings suggest a strong need for clinicians and researchers to collaborate to standardize documentation of menopausal palpitations across the menopause transition.
Performance-based assessment in the 21st century: when the examiner is a machine
Authors: Hodges Brian D.
Published: January 2021

None
What is the best long-term treatment modality for immature permanent teeth with pulp necrosis and apical periodontitis?
Authors: Wikström A. , Brundin M. , Lopes M. F. , El Sayed M. , Tsilingaridis G.
Published: January 2021

Purpose

To evaluate and assess the current knowledge about apexification and regenerative techniques as a meaningful treatment modality and to map the scientific evidence for the efficacy of both methods for the management of traumatised immature teeth with pulp necrosis and apical periodontitis.

Methods

This systematic review searched five databases: PubMed, Web of Science, Cochrane Library, Ovid (Medline), and Embase. Published articles written in English were considered for inclusion. The following keywords were used: Regenerative endodontic treatment OR regenerat* OR revital* OR endodontic regeneration OR regenerative endodontics OR pulp revascularization OR revasculari* OR ‘traumatized immature teeth’. Only peer-reviewed studies with a study size of at least 20 cases followed up for 24 months were included. Eligibility assessment was performed independently in a blinded manner by three reviewers and disagreements were resolved by consensus. Subgroup analyses were performed on three clinical outcomes: survival, success, and continued root development.

Results

Seven full texts out of 1359 citations were included and conventional content analysis was performed. Most of the identified citations were case reports and case series.

Conclusions

In the present systematic review, the qualitative analysis revealed that both regenerative and apexification techniques had equal rates of success and survival and proved to be effective in the treatment of immature necrotic permanent teeth. Endodontic regenerative techniques appear to be superior to apexification techniques in terms of stimulation of root maturation, i.e. root wall thickening and root lengthening. Knowledge gaps were identified regarding the treatment and follow-up protocols for both techniques.
Superlubricity of molybdenum disulfide subjected to large compressive strains
Authors: Wu Shengcong , Meng Zhisen , Tao Xiaoma , Wang Zhao
Published: January 2021

The friction between a molybdenum disulphide (MoS2) nanoflake and a MoS2 substrate was analyzed using a modified Tomlinson model based on atomistic force fields. The calculations performed in the study suggest that large deformations in the substrate can induce a dramatic decrease in the friction between the nanoflake and the substrate to produce the so-called superlubricity. The coefficient of friction decreases by 1–4 orders of magnitude when a high strain exceeding 0.1 is applied. This friction reduction is strongly anisotropic. For example, the reduction is most pronounced in the compressive regime when the nanoflake slides along the zigzag crystalline direction of the substrate. In other sliding directions, the coefficient of friction will reduce to its lowest value either when a high tensile strain is applied along the zigzag direction or when a high compressive strain is applied along the armchair direction. This anisotropy is correlated with the atomic configurations of MoS2.
Joint Estimation of Inconsistency and State of Health for Series Battery Packs
Authors: Che Yunhong , Foley Aoife , El-Gindy Moustafa , Lin Xianke , Hu Xiaosong , Pecht Michael
Published: January 2021

Battery packs are applied in various areas (e.g., electric vehicles, energy storage, space, mining, etc.), which requires the state of health (SOH) to be accurately estimated. Inconsistency, also known as cell variation, is considered a significant evaluation index that greatly affects the degradation of battery pack. This paper proposes a novel joint inconsistency and SOH estimation method under cycling, which fills the gap of joint estimation based on the fast-charging process for electric vehicles. First, fifteen features are extracted from current change points during the partial charging process. Then, a joint estimation system is designed, where fusion weights are obtained by the analytic hierarchy process and multi-scale sample entropy to evaluate inconsistency. A wrapper is used to select the optimal feature subset, and Gaussian process regression is implemented to estimate the SOH. Finally, the estimation performance is assessed by the test data. The results show that the inconsistency evaluation can reflect the aging conditions, and the inconsistency does affect the aging process. The wrapper selection method improves the accuracy of SOH estimation by about 75.8% compared to the traditional filter method when only 10% of data is used for model training. The maximum absolute error and root mean square error are 2.58% and 0.93%, respectively.
A Novel Electric Dual Motor Transmission for Heavy Commercial Vehicles
Authors: Xu Xiangyang , Liang Jiajia , Hao Qingjun , Dong Peng , Wang Shuhan , Guo Wei , Liu Yanfang , Lu Zhonghua , Geng Jiantao , Yan Bin
Published: January 2021

As a vital vehicle part, the powertrain system is undergoing a fast transition towards electrification. The new integrated electric drive system has been widely used, especially for passenger cars. In this work, a novel electric dual motor transmission is proposed for heavy commercial vehicles. The transmission scheme is firstly introduced, which can achieve 9 different operating modes including 5 single motor modes and 4 dual motor modes. Then, the mode shift map with minimum energy consumption is designed based on the motor efficiency map and the proposed energy management strategy. The driving power is appropriately distributed between the two motors in dual motor modes under the condition of minimum power consumption. In addition, a coordinated control strategy is developed for mode shift control without power interruption. The results show that the electric dual motor transmission has advantages in power consumption and power shift ability compared with the conventional single motor automated manual transmission.
Implementation of Dahl’s dynamic friction model to contact mechanics of elastic solids
Authors: Balci Mehmet N.
Published: January 2021

This study presents an analytical method for the solution of dynamic frictional contact problem between a rigid punch and an isotropic elastic solid. Rigid flat punch moves over the isotropic elastic solid at a constant subsonic speed and friction force develops based on Dahl’s friction law instead of Coulomb’s dry friction law. Dahl’s dynamic friction model is adopted since this model is one of the well-known dynamic friction models in the literature. According to this model, friction force depends only on a displacement rather than the speed of the punch since viscous effects are ignored. Influences of the parameters describing Dahl’s friction model on contact stress at slow and high speed sliding cases are examined. Analytical solution is conducted by means of Galilean and Fourier transformations. Friction force is computed numerically by the use of 4th order Runge–Kutta method for various displacements of the punch. Formulation for the contact problem is reduced to a singular integral equation and normal stress over the surface of elastic half-plane is determined. Obtained contact stresses are compared with those generated through finite element method and results display a high degree of accuracy. The influences of direction of motion, Coulomb’s coefficient of friction, pre-sliding displacement, asperity stiffness and shape factor of hysteresis loop upon contact stresses and stress intensity factors are revealed.
Evaluation of furrow fertigation on nitrogen supply and losses as a function of maize growth stages
Authors: Mohseni Amir , Hosseini Hossein Mirseyed , Abbasi Fariborz
Published: January 2021

The purpose of this study was to evaluate the effects of furrow fertigation on nitrate deep leaching, nitrate runoff losses, and plant nitrogen supply in various growth stages of maize (Zea maysL.). Furrow fertigation experiment was conducted in 120 (W1), 100 (W2), 80 (W3), and 60% (W4) levels of required water (560 mm) and 100 (N1), 80 (N2), 60 (N3), and 0% (N4) levels of required nitrogen fertilizer (184 kg N ha−1). N-fertilizer was applied in four split applications (before planting, at the seven-leaf, shooting, and flowering). In the farmers’ conventional fertilization (FCF) method, 120% level of required water and 100% level of the required N-fertilizer were used in two split applications (before planting and at the seven-leaf stage). Results showed that the highest maize aboveground nitrogen content was 3.11% for FCF treatments at the seven-leaf stage. The maximum nitrogen content in the sensitive flowering stage and the maximum grain yield were also observed in W2N1 treatment with 2.27% and 12.93 ton ha−1, respectively. While, there were no significant differences in aboveground nitrogen content and grain yield between W2N1 and W3N1, W2N2, and W3N2. The highest amounts of nitrate leaching out of the 80-cm soil layer and nitrate runoff losses, were also recorded in FCF treatment, followed by W1N1, W2N1, and W3N1. Based on plant nitrogen content, nitrate losses and maize yield, 80% levels of the required N-fertilizer and required irrigation water could be recommended as the optimal levels to reduce nitrate losses and improve maize yield.
Co-pyrolysis of lignite and rapeseed cake: a comparative study on the thermal decomposition behavior and pyrolysis kinetics
Authors: Yaman Elif , Ulusal Aysu , Uzun Başak Burcu
Published: January 2021

In this study, physicochemical properties, co-pyrolysis kinetics and characteristics of lignite and rapeseed cake is investigated. While lignite has high calorific value, rapeseed cake has high volatile matter content and low moisture content that is suitable for the pyrolysis reactions. According to the thermal behavior of lignite and rapeseed cake blends, the addition of rapeseed cake into lignite provides to shift to lower initial decomposition temperature of blends compared to lignite. While rapeseed cake has a significant role in determining activation energies at the lower conversion degrees, lignite plays a vital role in specifying the activation energies at the higher conversion degrees. The char yield considerably decreases under the higher rapeseed cake ratio, while both of the bio-oil and gas yields increase. As conclusion, blending of rapeseed cake with lignite provides a positive synergy with regard to volatile yields and follows through different types of chemicals that can be valorized in various applications such as bio-chemicals and bio-fuel.