bluuebunny/crossref_metadata_2025 huggingface dataset:
ACE2 activation protects against cognitive decline and reduces amyloid pathology in the Tg2576 mouse model of Alzheimer’s disease
Authors: Evans Charles E. , Miners James S. , Piva Giulia , Willis Christine L. , Heard David M. , Kidd Emma J. , Good Mark A. , Kehoe Patrick G.
Published: January 2020

Mid-life hypertension and cerebrovascular dysfunction are associated with increased risk of later life dementia, including Alzheimer’s disease (AD). The classical renin–angiotensin system (cRAS), a physiological regulator of blood pressure, functions independently within the brain and is overactive in AD. cRAS-targeting anti-hypertensive drugs are associated with reduced incidence of AD, delayed onset of cognitive decline, and reduced levels of Aβ and tau in both animal models and human pathological studies. cRAS activity is moderated by a downstream regulatory RAS pathway (rRAS), which is underactive in AD and is strongly associated with pathological hallmarks in human AD, and cognitive decline in animal models of CNS disease. We now show that enhancement of brain ACE2 activity, a major effector of rRAS, by intraperitoneal administration of diminazene aceturate (DIZE), an established activator of ACE2, lowered hippocampal Aβ and restored cognition in mid-aged (13–14-month-old) symptomatic Tg2576 mice. We confirmed that the protective effects of DIZE were directly mediated through ACE2 and were associated with reduced hippocampal soluble Aβ42 and IL1-β levels. DIZE restored hippocampal MasR levels in conjunction with increased NMDA NR2B and downstream ERK signalling expression in hippocampal synaptosomes from Tg2576 mice. Chronic (10 weeks) administration of DIZE to pre-symptomatic 9–10-month-old Tg2576 mice, and acute (10 days) treatment in cognitively impaired 12–13-month-old mice, prevented the development of cognitive impairment. Together these data demonstrate that ACE2 enhancement protects against and reverses amyloid-related hippocampal pathology and cognitive impairment in a preclinical model of AD.
Ramsay Hunt syndrome: characteristics and patient self-assessed long-term facial palsy outcome
Authors: Kanerva Mervi , Jones Sanna , Pitkaranta Anne
Published: January 2020

Purpose

To explore the characteristics, medical treatments, and long-term facial palsy outcome in Ramsay Hunt syndrome.

Methods

Patient questionnaire including self-assessment of long-term facial palsy outcome and retrospective chart review. Initial facial palsy grade was compared to self-assessed or patient record stated palsy outcome. Occurrence of different characteristics (blisters, hearing loss, vertigo, etc.) of the syndrome were assessed.

Results

Altogether 120 patients were included of which 81 answered the questionnaire. All but one patient had received virus medication (aciclovir, valaciclovir), and half received simultaneous corticosteroids. If the medication was started within 72 h of Ramsay Hunt diagnosis, facial palsy recovered totally or with only slight sequelae in over 80% of the patients. Only a minority of the patients experienced varicella blisters simultaneously with facial palsy, blisters more often preceded or followed the palsy. Approximately 20% of the patients had their blisters in hidden places in the ear canal or mouth.

Conclusions

The long-term outcome of facial palsy in medically treated Ramsay Hunt syndrome was approaching the outcome of Bell’s palsy. It is crucial to ask and inform the patient about the blisters and look for them since, more often than not, the blisters precede or follow the palsy and can be in areas not easily seen.
Treatment patterns and survival after 18F-fluorodeoxyglucose positron emission tomography/computed tomography-guided local consolidation therapy for oligometastatic non-small cell lung cancer: a two-center propensity score-matched analysis
Authors: Song Ying-Qiu , Wang Nan , Qiao Yun , He Lei , Li Xia , Zhang Xiao-Fang , Yang Qian-Kun , Wang Run-Ze , He Rong , Wang Chen-Yu , Ren Yang-Wu , Li Guang , Wang Tian-Lu
Published: January 2020

Purpose

In this retrospective study, we evaluated the treatment patterns and survival after positron emission tomography-computed tomography (PET/CT)-guided local consolidation therapy (LCT) for oligometastatic non-small cell lung cancer (NSCLC).

Methods

We reviewed the medical records of Chinese patients with oligometastatic stage IV non-small cell lung cancer (≤ 5 metastases) who had undergone PET/CT and were eligible for systemic therapy at two centers between May 2005 and August 2019. Propensity score matching (1:1) was used to reduce selection bias and imbalanced distribution of confounding factors.

Results

We identified 84 eligible patients and used propensity scores to create well-matched groups of 35 patients who did or did not undergo LCT. Among all patients, the 1-year overall survival (OS) rate was 47.6% and the 2-year OS rate was 22.6%. Relative to the group that did not receive LCT, the LCT group had a significantly higher OS rate (13 months vs. 7 months, p = 0.002). The two groups had similar incidences and classifications of LCT-related side effects. In multivariable analysis, LCT was found to be strongly associated with a favorable OS (hazard ratio: 0.508, 95% confidence interval: 0.311–0.828, p = 0.001).

Conclusion

We concluded that LCT was significantly associated with improved clinical outcomes among the Chinese patients with oligometastatic NSCLC who were eligible for systemic treatment and could undergo PET/CT evaluation.
Mathematical modelling supports the existence of a threshold hydrogen concentration and media-dependent yields in the growth of a reductive acetogen
Authors: Smith Nick W. , Shorten Paul R. , Altermann Eric , Roy Nicole C. , McNabb Warren C.
Published: January 2020

The bacterial production of acetate via reductive acetogenesis along the Wood–Ljungdahl metabolic pathway is an important source of this molecule in several environments, ranging from industrial bioreactors to the human gastrointestinal tract. Here, we contributed to the study of reductive acetogens by considering mathematical modelling techniques for the prediction of bacterial growth and acetate production. We found that the incorporation of a hydrogen uptake concentration threshold into the models improves their predictions and we calculated this threshold as 86.2 mM (95% confidence interval 6.1–132.6 mM). Monod kinetics and first-order kinetics models, with the inclusion of two candidate threshold terms or reversible Michaelis–Menten kinetics, were compared to experimental data and the optimal formulation for predicting both growth and metabolism was found. The models were then used to compare the efficacy of two growth media for acetogens. We found that the recently described general acetogen medium was superior to the DSMZ medium in terms of unbiased estimation of acetogen growth and investigated the contribution of yeast extract concentration to acetate production and bacterial growth in culture. The models and their predictions will be useful to those studying both industrially and environmentally relevant reductive acetogenesis and allow for straightforward adaptation to similar cases with different organisms.
Tracking changes in user activity from unlabelled smart home sensor data using unsupervised learning methods
Authors: Gupta Prankit , McClatchey Richard , Caleb-Solly Praminda
Published: January 2020

This paper investigates the utility of unsupervised machine learning and data visualisation for tracking changes in user activity over time. This is done through analysing unlabelled data generated from passive and ambient smart home sensors, such as motion sensors, which are considered less intrusive than video cameras or wearables. The challenge in using unlabelled passive and ambient sensors data for activity recognition is to find practical methods that can provide meaningful information to support timely interventions based on changing user needs, without the overhead of having to label the data over long periods of time. The paper addresses this challenge to discover patterns in unlabelled sensor data using kernel density estimation (KDE) for pre-processing the data, together with t-distributed stochastic neighbour embedding and uniform manifold approximation and projection for visualising changes. The methodology is developed and tested on the Aruba CASAS smart home dataset and focusses on discovering and tracking changes in kitchen-based activities. The traditional approach of using sliding windows to segment the data requires a priori knowledge of the temporal characteristics of activities being identified. In this paper, we show how an adaptive approach for segmentation, KDE, is a suitable alternative for identifying temporal clusters of sensor events from unlabelled data that can represent an activity. The ability to visualise different recurring patterns of activity and changes to these over time is illustrated by mapping the data for separate days of the week. The paper then demonstrates how this can be used to track patterns over longer time-frames which could be used to help highlight differences in the user’s day-to-day behaviour. By presenting the data in a format that can be visually reviewed for temporal changes in activity over varying periods of time from unlabelled sensor data, opens up the opportunity for carers to then initiate further enquiry if variations to previous patterns are noted. This is seen as an accessible first step to enable carers to initiate informed discussions with the service user to understand what may be causing these changes and suggest appropriate interventions if the change is found to be detrimental to their well-being.
Early cost-utility analysis of tissue-engineered heart valves compared to bioprostheses in the aortic position in elderly patients
Authors: Huygens Simone A. , Ramos Isaac Corro , Bouten Carlijn V. C. , Kluin Jolanda , Chiu Shih Ting , Grunkemeier Gary L. , Takkenberg Johanna J. M. , Rutten-van Mölken Maureen P. M. H.
Published: January 2020

Objectives

Aortic valve disease is the most frequent indication for heart valve replacement with the highest prevalence in elderly. Tissue-engineered heart valves (TEHV) are foreseen to have important advantages over currently used bioprosthetic heart valve substitutes, most importantly reducing valve degeneration with subsequent reduction of re-intervention. We performed early Health Technology Assessment of hypothetical TEHV in elderly patients (≥ 70 years) requiring surgical (SAVR) or transcatheter aortic valve implantation (TAVI) to assess the potential of TEHV and to inform future development decisions.

Methods

Using a patient-level simulation model, the potential cost-effectiveness of TEHV compared with bioprostheses was predicted from a societal perspective. Anticipated, but currently hypothetical improvements in performance of TEHV, divided in durability, thrombogenicity, and infection resistance, were explored in scenario analyses to estimate quality-adjusted life-year (QALY) gain, cost reduction, headroom, and budget impact.

Results

Durability of TEHV had the highest impact on QALY gain and costs, followed by infection resistance. Improved TEHV performance (− 50% prosthetic valve-related events) resulted in lifetime QALY gains of 0.131 and 0.043, lifetime cost reductions of €639 and €368, translating to headrooms of €3255 and €2498 per hypothetical TEHV compared to SAVR and TAVI, respectively. National savings in the first decade after implementation varied between €2.8 and €11.2 million (SAVR) and €3.2–€12.8 million (TAVI) for TEHV substitution rates of 25–100%.

Conclusions

Despite the relatively short life expectancy of elderly patients undergoing SAVR/TAVI, hypothetical TEHV are predicted to be cost-effective compared to bioprostheses, commercially viable and result in national cost savings when biomedical engineers succeed in realising improved durability and/or infection resistance of TEHV.
High-energy events in the Frasnian–Famennian boundary interval of the Płucki section in the Holy Cross Mountains, Poland
Authors: Szrek Piotr , Salwa Sylwester
Published: January 2020

Of all the Devonian stratigraphic boundaries, the Frasnian–Famennian transition (372.2 ± 1.6 Ma) preserves the record of one of the most significant crises in the history of life, the final stages of which lie buried in the distinctive Kellwasser limestone. The Kellwasser facies occur in Western and Central Europe and the commonly cited Płucki area of Poland’s geologically rich Holy Cross Mountains is the only site in that region where the Frasnian–Famennian boundary is considered to occur within Kellwasser facies. At this locality, the limestone contains slump structures, comprising contorted beds and folds. Actually the Kellwasser-like limestone from Płucki is composed of a mixture of three distinct types of sediment, occurring as clasts, commonly deformed and sheared, and matrix, rather than being one homogenous bed, as previously considered. Thus, earlier studies and interpretations of this limestone may need revising. This paper documents the evidence for sediment erosion and reworking, debris flows, sliding and soft-sediment deformation on a submarine slope, and suggests that seismic events were the likely triggering mechanism for slumping and resedimentation.
Assignment constraints in shared transportation services
Authors: Gansterer Margaretha , Hartl Richard F. , Wieser Sarah
Published: January 2020

Competitive markets, increased fuel costs, and underutilized vehicle fleets are characteristics that currently define the logistics sector. Given an increasing pressure to act in a manner that is economically and ecologically efficient, mechanisms that help to benefit from idle capacities are on the rise. In the Sharing Economy, collaborative usage is typically organized through platforms that facilitate the exchange of goods or services. Our study examines a collaborative pickup and delivery problem where carriers can exchange customer requests. The aim is to quantify the potential of horizontal collaborations under a centralized framework. An Adaptive Large Neighborhood Search is developed to solve yet unsolved test instances. A computational study confirms the results of past studies which have reported cost savings between 20 and 30%. In addition, the numerical results indicate an even greater potential for settings with a high degree of regional customer overlap. Unfortunately, these high collaborative gains typically come at the cost of an uneven customer distribution, which is known to be one of the main barriers that prevent companies from entering into horizontal collaborations. To generate acceptable solutions for all participants, several constraints are included in the model. The introduction of these constraints to single-vehicle instances, decreases the potential collaborative gain considerably. Surprisingly, this does not happen in more realistic settings of carriers operating multiple vehicles. Overall, the computational study shows that centralized collaborative frameworks have the potential to generate considerable cost savings, while at the same time limiting customer or profit share losses and enabling carriers to keep some of their most valued customers.
Range-wide patterns of human-mediated hybridisation in European wildcats
Authors: Tiesmeyer Annika , Ramos Luana , Manuel Lucas José , Steyer Katharina , Alves Paulo C. , Astaras Christos , Brix Mareike , Cragnolini Margherita , Domokos Csaba , Hegyeli Zsolt , Janssen René , Kitchener Andrew C. , Lambinet Clotilde , Mestdagh Xavier , Migli Despina , Monterroso Pedro , Mulder Jaap L. , Schockert Vinciane , Youlatos Dionisios , Pfenninger Markus , Nowak Carsten
Published: January 2020

Hybridisation between wild taxa and their domestic congeners is a significant conservation issue. Domestic species frequently outnumber their wild relatives in population size and distribution and may therefore genetically swamp the native species. The European wildcat (Felis silvestris) has been shown to hybridise with domestic cats (Felis catus). Previously suggested spatially divergent introgression levels have not been confirmed on a European scale due to significant differences in the applied methods to assess hybridisation of the European wildcat. We analysed 926Felisspp. samples from 13 European countries, using a set of 86 selected ancestry-informative SNPs, 14 microsatellites, and ten mitochondrial and Y-chromosome markers to study regional hybridisation and introgression patterns and population differentiation. We detected 51 hybrids (four F1 and 47 F2 or backcrosses) and 521 pure wildcats throughout Europe. The abundance of hybrids varied considerably among studied populations. All samples from Scotland were identified as F2 hybrids or backcrosses, supporting previous findings that the genetic integrity of that wildcat population has been seriously compromised. In other European populations, low to moderate levels of hybridisation were found, with the lowest levels being in Central and Southeast Europe. The occurrence of distinct maternal and paternal markers between wildcat and domestic cat suggests that there were no severe hybridisation episodes in the past. The overall low (< 1%) prevalence of F1 hybrids suggests a low risk of hybridisation for the long-term genetic integrity of the wildcat in most of Europe. However, regionally elevated introgression rates confirm that hybridisation poses a potential threat. We propose regional in-depth monitoring of hybridisation rates to identify factors driving hybridisation so as to develop effective strategies for conservation.
Pupil Response to Affective Stimuli: a Biomarker of Early Conduct Problems in Young Children
Authors: Burley Daniel T. , van Goozen Stephanie H.M.
Published: January 2020

Childhood conduct problems have been associated with reduced autonomic arousal to negative cues indicative of an insensitivity to aversive stimuli, with mixed evidence in response to positive cues. Autonomic arousal to affective stimuli has traditionally been measured through galvanic skin responses and heart-rate, despite evidence that pupillometry is more reliable and practically beneficial (i.e., no wires are attached to the participant). The current study is the first to examine abnormal pupillary responsivity to affective stimuli as a biomarker for childhood conduct problems. We measured pupil reactivity to negative, positive and neutral images in 131 children aged 4–7 years, who were referred by their teachers for being at risk of future psychopathology. We assessed relationships between pupil response to the images and teacher-rated scores on the Strengths and Difficulties Questionnaire (SDQ), which indexed child conduct problems and their overlapping emotional, behavioural and social difficulties. Reduced pupil dilation to negative images was associated with significantly increased conduct, hyperactivity, emotional and peer problems, as well as reduced prosocial behaviour. Composite scores for disruptive behaviour and emotional difficulties both uniquely predicted blunted pupil response to negative threat stimuli; there were no relations with pupil responses to positive images. These findings highlight that blunted pupil responsivity to negative stimuli serves as a biomarker for early disruptive behavioural problems and affective difficulties. Pupillometry offers an inexpensive, fast and non-intrusive measure to help identify children who are showing early disruptive behaviour or experiencing affective difficulties, which can provide opportunities for preventative intervention to avoid further psychopathology.
Semiparametric regression and risk prediction with competing risks data under missing cause of failure
Authors: Bakoyannis Giorgos , Zhang Ying , Yiannoutsos Constantin T.
Published: January 2020

The cause of failure in cohort studies that involve competing risks is frequently incompletely observed. To address this, several methods have been proposed for the semiparametric proportional cause-specific hazards model under a missing at random assumption. However, these proposals provide inference for the regression coefficients only, and do not consider the infinite dimensional parameters, such as the covariate-specific cumulative incidence function. Nevertheless, the latter quantity is essential for risk prediction in modern medicine. In this paper we propose a unified framework for inference about both the regression coefficients of the proportional cause-specific hazards model and the covariate-specific cumulative incidence functions under missing at random cause of failure. Our approach is based on a novel computationally efficient maximum pseudo-partial-likelihood estimation method for the semiparametric proportional cause-specific hazards model. Using modern empirical process theory we derive the asymptotic properties of the proposed estimators for the regression coefficients and the covariate-specific cumulative incidence functions, and provide methodology for constructing simultaneous confidence bands for the latter. Simulation studies show that our estimators perform well even in the presence of a large fraction of missing cause of failures, and that the regression coefficient estimator can be substantially more efficient compared to the previously proposed augmented inverse probability weighting estimator. The method is applied using data from an HIV cohort study and a bladder cancer clinical trial.
Reactive Astrocytes as Therapeutic Targets for Brain Degenerative Diseases: Roles Played by Metabotropic Glutamate Receptors
Authors: Planas-Fontánez Talia M. , Dreyfus Cheryl F. , Saitta Kyle S.
Published: January 2020

Astrocytes are well known to play critical roles in the development and maintenance of the central nervous system (CNS). Moreover, recent reports indicate that these cells are heterogeneous with respect to the molecules they express and the functions they exhibit in the quiescent or activated state. Because astrocytes also contribute to pathology, promising new results raise the possibility of manipulating specific astroglial populations for therapeutic roles. In this mini-review, we highlight the function of metabotropic glutamate receptors (mGluRs), in particular mGluR3 and mGluR5, in reactive astrocytes and relate these to three degenerative CNS diseases: multiple sclerosis, Alzheimer’s disease and Amyotrophic Lateral Sclerosis. Previous studies demonstrate that effects of these receptors may be beneficial, but this varies depending on the subtype of receptor, the state of the astrocytes, and the specific disease to which they are exposed. Elucidating the role of mGluRs on astrocytes at specific times during development and disease will provide novel insights in understanding how to best use these to serve as therapeutic targets.
Peptide transporter2 (PTR2) enhances water uptake during early seed germination in Arabidopsis thaliana
Authors: Choi Myoung-Goo , Kim Eui Joong , Song Ji-Young , Choi Sang-Bong , Cho Seong-Woo , Park Chul Soo , Kang Chon-Sik , Park Youn-Il
Published: January 2020

Key message

PTR2 inArabidopsis thalianais negatively regulated by ABI4 and plays a key role in water uptake by seeds, ensuring that imbibed seeds proceed to germination.

Peptide transporters (PTRs) transport nitrogen-containing substrates in a proton-dependent manner. Among the six PTRs inArabidopsis thaliana, the physiological role of the tonoplast-localized, seed embryo abundant PTR2 is unknown. In the present study, a molecular physiological analysis of PTR2 was conducted usingptr2mutants andPTR2COcomplementation lines. Compared with the wild type, theptr2mutant showed ca. 6 h delay in testa rupture and consequently endosperm rupture because of 17% lower water content and 10% higher free abscisic acid (ABA) content. Constitutive overexpression of thePTR2gene under the control of the Cauliflower mosaic virus (CaMV)35Spromoter inptr2mutants rescued the mutant phenotypes. After cold stratification, a transient increase inABA INSENSITIVE4(ABI4) transcript levels during induction of testa rupture was followed by a similar increase inPTR2transcript levels, which peaked prior to endosperm rupture. ThePTR2promoter region containing multiple CCAC motifs was recognized by ABI4 in electrophoretic mobility shift assays, andPTR2expression was repressed by 67% inABI4overexpression lines compared with the wild type, suggesting that PTR2 is an immediate downstream target of ABI4. Taken together, the results suggest that ABI4-dependent temporal regulation ofPTR2expression may influence water status during seed germination to promote the post-germinative growth of imbibed seeds.
What drives the gap? Applying the Blinder–Oaxaca decomposition method to examine generational differences in transportation-related attitudes
Authors: Etezady Ali , Shaw F. Atiyya , Mokhtarian Patricia L. , Circella Giovanni
Published: January 2020

Considerable recent work suggests that Millennials’ behaviors may be converging with those of Generation X as they enter later life stages, but few have investigated whether attitudes, which are often strong predictors of behavior, are undergoing the same convergence. In this study, we analyze the existing generational gap in four transportation-related attitudes (currently pro-urban, long-term pro-urban, pro-car ownership, and pro-environment), and examine the differential effects of other characteristics, including life-stage variables, on these attitudinal gaps. We apply the threefold Blinder–Oaxaca decomposition method to a statewide (weighted) sample of 1029 Millennials and 946 Generation Xers from California to unravel these effects. The method distinguishes among: (1) effects due to the cohorts having different characteristics (endowments); (2) effects due to those characteristics having different influences on attitudes (coefficients); and (3) the interaction of those two effects. We observe that Millennials’ attitudes: (1) differ from those of Generation X only by small, albeit statistically significant, amounts on average; and (2) are closer to those of Generation X as they gain on a host of life-stage variables such as marital status, income, and education. For example, if Millennials were married, employed, and earning higher incomes at the same rates as Generation X (but retaining their own model coefficients), the generational gap in the currently pro-urban attitude would be reduced by 24%. This study brings an econometric approach to the study of generational divides in transportation-related attitudes, with findings suggesting that Millennials might be leaving part of their uniqueness behind as they enter later life stages.
On the Impact of Learning Cycle Teaching on Austrian High School Students’ Emotions, Academic Self-Concept, Engagement, and Achievement
Authors: Riffert Franz , Hagenauer Gerda , Kriegseisen Josef , Strahl Alexander
Published: January 2020

Over the past several decades, empirical support for inquiry-based forms of science teaching has accumulated. Critical voices, however, also exist, claiming that minimally guided teaching approaches might be less effective than guided forms; they might even be harmful, particularly for novice students, due to the production of cognitive overload. In this study, a more guided type of inquiry-based forms of instruction was therefore selected, which can be traced back to Alfred N. Whitehead: the so-called learning cycle approach. This approach was applied to science classes with 280 socioeconomically disadvantaged students in lower secondary education at low-track schools in Austria. Using a pre-test post-test experimental-control group design, this study investigated the effects of this instructional approach not only concerning students’ cognitive development but also concerning their state and trait emotions, their behavioral engagement in class, and their academic self-concept. The results indicated that the application of the learning cycle approach had a positive impact on most of the measured students’ trait emotions and state emotions during the romance and generalization phases of a full learning cycle. It further improved the students’ behavioral engagement during lessons and strengthened their academic self-concept. Finally, it was found that the learning cycle approach positively affected the students’ cognitive development after the 2-year treatment. Suggestions for improving the implementation of this teaching approach in science classes are given; some proposals for optimizing future research on learning cycle teaching are also made.
Forecasting emerging technologies using data augmentation and deep learning
Authors: Zhou Yuan , Dong Fang , Liu Yufei , Li Zhaofu , Du JunFei , Zhang Li
Published: January 2020

Deep learning can be used to forecast emerging technologies based on patent data. However, it requires a large amount of labeled patent data as a training set, which is difficult to obtain due to various constraints. This study proposes a novel approach that integrates data augmentation and deep learning methods, which overcome the problem of lacking training samples when applying deep learning to forecast emerging technologies. First, a sample data set was constructed using Gartner’s hype cycle and multiple patent features. Second, a generative adversarial network was used to generate many synthetic samples (data augmentation) to expand the scale of the sample data set. Finally, a deep neural network classifier was trained with the augmented data set to forecast emerging technologies, and it could predict up to 77% of the emerging technologies in a given year with high precision. This approach was used to forecast emerging technologies in Gartner’s hype cycles for 2017 based on patent data from 2000 to 2016. Four out of six of the emerging technologies were forecasted correctly, showing the accuracy and precision of the proposed approach. This approach enables deep learning to forecast emerging technologies with limited training samples.
Discovering seminal works with marker papers
Authors: Haunschild Robin , Marx Werner
Published: January 2020

Bibliometric information retrieval in databases can employ different strategies. Commonly, queries are performed by searching in title, abstract and/or author keywords (author vocabulary). More advanced queries employ database keywords to search in a controlled vocabulary. Queries based on search terms can be augmented with their citing papers if a research field cannot be curtailed by the search query alone. Here, we present another strategy to discover the most important papers of a research field. A marker paper is used to reveal the most important works for the relevant community. All papers co-cited with the marker paper are analyzed using reference publication year spectroscopy (RPYS). For demonstration of the marker paper approach, density functional theory is used as a research field. Comparisons between a prior RPYS on a publication set compiled using a keyword-based search in a controlled vocabulary and three different co-citation RPYS analyses show very similar results. Similarities and differences are discussed.
Investigating the process of entrepreneurial team member exits: a systematic review and future research directions
Authors: Gregori Patrick , Parastuty Zulaicha
Published: January 2020

Entrepreneurial teams are dynamic entities that frequently experience the exit of individual team members. Such entrepreneurial team member exits (ETMEs) entail serious consequences for the exiting individual, the remaining team, and the performance of the affected venture. While ETMEs are receiving increasing scholarly attention, the research landscape is still considerably fragmented. This is the first article to take stock, analyze, and discuss this crucial and emerging field of research by providing a systematic review of the literature on ETMEs. We identify central themes comprising of antecedents, routes, consequences, and the contextual embeddedness of ETMEs and integrate them into a comprehensive processual framework. Based on this framework, we contribute to the research on ETMEs by discussing the themes in the light of promising theoretical perspectives, introducing novel ideas, concepts, and approaches to enrich future avenues. Specifically, we propose to expand the concept of team heterogeneity to advance our understanding of antecedents as well as to investigate power relations and negotiation behavior within ETME routes. In addition, we offer ways to resolve the sometimes inconsistent findings in terms of venture consequences and present a fertile approach for a more in-depth cultural contextualization of the phenomenon.
Comparative study on physicochemical status and diversity of macrophytes and zooplanktons of two urban ponds of Chandannagar, WB, India
Authors: Sarkar Rituparna , Ghosh Apurba Ratan , Mondal Naba Kumar
Published: January 2020

Present investigation has made an attempt to assess the variations in physicochemical status of two urban ponds (constructed boundary: Pond A and natural boundary: Pond B) of Chandannagar and also established the variations in the diversity of macrophytes and zooplankton of the study areas during winter (Nov–Dec, 2017). Limnological parameters recorded from two spots collected in three phases, such as temperature, pH, transparency, conductivity, DO, BOD, total dissolved solids (TDS), total suspended solids (TSS), total alkalinity, total hardness and chloride, were evaluated. From this observation, it is reported that there are marked variations in different water quality parameters of two urban ponds during the study period. The value of water temperature in Pond A and B was 22.0 and 21.3 °C, respectively. pH value (7.9) was highest in Pond B. Pond B water was more turbid than Pond A. The highest values of other parameters like conductivity (218.50 µS/cm) DO (8.47 mg/l), BOD (5.69 mg/l), TDS (135.19 mg/l), TSS (67.60 mg/l), total alkalinity (181.15 mg/l), total hardness (145.66 mg/l) and chloride (58.94 mg/l) were found in case of Pond B. Maximum macrophytic vegetations were found in Pond B in comparison with Pond A. The study of the zooplankton community reveals that the maximum occurrence of rotifers in Pond B indicates pollution status.
Mean stress correction in fatigue design under consideration of welding residual stress
Authors: Hensel Jonas
Published: January 2020

The fatigue strength of welded steels is affected by the applied load mean stress and the residual stress in the vicinity of the weld. The mean stress correction in fatigue design concepts used for welded structures commonly distinguishes between three subjective generalized residual stress conditions, “low, medium, and high” tensile residual stress. This qualitative treatment of residual stress leads to imprecise evaluation of residual stress effects, in particular when compressive residual stress is present or high-strength steels are applied. The objectives of the underlying study are to emphasize the interaction of load mean stress with residual stress and to provide an approach for the combined treatment of those stress components in the nominal stress concept. The principles of mean stress and residual stress effects on fatigue are presented and discussed. Furthermore, the role of residual stress relaxation is emphasized and cyclically stabilized local residual stress is combined with mean stress to effective mean stress. The fatigue design concept of local endurance limits and effective mean stress is introduced for the quantitative evaluation of residual and mean stress effects. Finally, the effective mean stress approach is applied to longitudinal stiffeners made from different steel grades containing various residual stress conditions. It is shown how design S-N curves can be adjusted based on quantitative effective mean stress. Finally, an improved bonus factor concept based on effective mean stress is presented, which allows a mean stress correction under consideration of the residual stress condition.
Three-Dimensional Self-assembled Hairball-Like VS4 as High-Capacity Anodes for Sodium-Ion Batteries
Authors: Ding Shuangshuang , Zhou Bingxin , Chen Changmiao , Huang Zhao , Li Pengchao , Wang Shuangyin , Cao Guozhong , Zhang Ming
Published: January 2020

Sodium-ion batteries (SIBs) are considered to be attractive candidates for large-scale energy storage systems because of their rich earth abundance and consistent performance. However, there are still challenges in developing desirable anode materials that can accommodate rapid and stable insertion/extraction of Na+ and can exhibit excellent electrochemical performance. Herein, the self-assembled hairball-like VS4 as anodes of SIBs exhibits high discharge capacity (660 and 589 mAh g−1 at 1 and 3 A g−1, respectively) and excellent rate property (about 100% retention at 10 and 20 A g−1 after 1000 cycles) at room temperature. Moreover, the VS4 can also exhibit 591 mAh g−1 at 1 A g−1 after 600 cycles at 0 °C. An unlike traditional mechanism of VS4 for Na+ storage was proposed according to the dates of ex situ characterization, cyclic voltammetry, and electrochemical kinetic analysis. The capacities of the final stabilization stage are provided by the reactions of reversible transformation between Na2S and S, which were considered the reaction mechanisms of Na–S batteries. This work can provide a basis for the synthesis and application of sulfur-rich compounds in fields of batteries, semiconductor devices, and catalysts.
On the Number of Simple $$K_4$$ Groups
Authors: Zhang Shaohua , Shi Wujie
Published: January 2020

In this paper, by solving Diophantine equations involving simple $$K_4$$

K
4

-groups, we will try to point out that it is not easy to prove the infinitude of simple $$K_4$$

K
4

-groups. This problem goes far beyond what is known about Dickson’s conjecture at present.
Simulation of the response of a segmented high-purity germanium detector for gamma emission tomography of nuclear fuel
Authors: Andersson Peter , Rathore Vikram , Senis Lorenzo , Anastasiadis Anastasios , Andersson Sundén Erik , Atak Haluk , Holcombe Scott , Håkansson Ane , Jansson Peter , Nyberg Johan
Published: January 2020

Irradiation testing of nuclear fuel is routinely performed in nuclear test reactors. For qualification and licensing of accident-tolerant fuels or generation IV reactor fuels, an extensive increase in irradiation testing is foreseen in order to fill the gaps of existing validation data, both in normal operational conditions and in order to identify operational limits. Gamma emission tomography (GET) has been demonstrated as a viable technique for studies of the behavior of irradiated nuclear fuel, e.g., measurement of fission gas release and inspection of fuel behavior under loss-of-coolant accident conditions. In this work, the aim is to improve the technique of GET for irradiated nuclear fuel, by developing a detector concept that allows for a higher spatial resolution and/or faster interrogation. We present the working principles of a novel concept for gamma emission tomography using a segmented high-purity germanium (HPGe) detector. The performance of this concept was investigated using the Monte Carlo particle transport code MCNP. In particular, the data analysis of the proposed detector was evaluated, and the performance, in terms of full energy efficiency and misidentification rate (i.e., localization failure), was assessed. We concluded that the segmented HPGe detector has an advantageous performance as compared to the traditional single-channel detector systems. Due to the scattering nature of gamma rays, a trade-off is presented between efficiency and cross-talk; however, the performance is nevertheless a substantial improvement over the currently used single-channel HPGe detector systems.
Full‐information factor analysis of the Daily Routine and Autonomy (DRA) questionnaire among adolescents with autism spectrum disorder
Authors: Lamash Liron , Josman Naomi
Published: January 2020

Introduction

Adolescents with autism spectrum disorder (ASD) show poor independence in daily activities. Unlike existing instruments, the innovative self‐report Daily Routine and Autonomy questionnaire (DRA) addresses their level of and desire for independence in activities throughout a full daily routine. This study describes the DRA development, explores its psychometric properties and internal consistency reliability using full‐information factor analysis (FIFA), and identifies levels of and desire for independence among adolescents with ASD.

Methods

Seventy‐two Israeli adolescents with ASD (58 boys and 14 girls) aged 11–19 years (M = 14.59, SD = 1.61) completed the DRA. Statistical analyses were performed using SPSS and R. Internal consistency reliability, FIFA, Spearman's correlations, t‐tests, and Wilcoxon signed‐rank were conducted to assess relationships and differences between the DRA parts.

Results

The FIFA revealed three factors with high sum‐of‐squared loadings (4.09–5.13). Of the 31 DRA items, 28 had factor loadings higher than 0.35 and were retained in the study questionnaire. The DRA had moderate‐to‐high internal reliability for factors (α = 0.65–0.84) and total scores (α = 0.86–0.90). Participants showed partial independence in most daily activities, with high desire for independence in social and leisure activities. Significant gaps in half of the DRA items indicate the participants' desire for independence was significantly higher than their independence level.

Conclusion

The DRA provides crucial information about levels of and desire for autonomy that can be used to promote participation of adolescents with ASD in setting their own goals for independent living.
Cross-Media Consumption: Insights from Super Bowl Advertising
Authors: Bharadwaj Neeraj , Ballings Michel , Naik Prasad A.
Published: January 2020

When viewers engage in cross-media consumption—view television advertising and social media posts on another medium—how do stimuli from multiple screens influence their response? To address this question, we construct a comprehensive dataset to estimate the effects of Super Bowl advertising and the advertised brands’ Facebook content on ad likability. The novel insights emerging from the analyses include that: both media directly and significantly impact the response, contributing 60% and 40%, respectively; thinking hurts liking; and an ad's serial position does not matter, which differs from the primacy and recency effects previously reported in advertising studies. This study contributes to the theory and practice by: (i) testing open research questions empirically regarding the complementary effects of two screens; (ii) extracting the formal, analytic, and narrative thinking styles from the actual words in social media comments; and (iii) demonstrating that divided attention across screens has negative consequences on viewer appraisals.
Additive manufacturing of soft and hard magnetic materials used in electrical machines
Authors: Bernier Fabrice , Ibrahim Maged , Mihai Mihaela , Thomas Yannig , Lamarre Jean-Michel
Published: January 2020

Soft and hard magnetic materials were fabricated using additive manufacturing (AM) for use in 3D electrical machines. The effect of the characteristics and the nature of the magnetic feedstock powders was evaluated for both the cold spray (CS) and the fused filament fabrication (FFF) processes. 3D finite element analysis (FEA) was used to develop new motor topologies based on the advantages offered by AM. FEA optimization also allowed the identification of the most critical material properties and is thus a powerful tool to facilitate material development.
Reclaiming rare earth metals
Authors: Nickels Liz
Published: January 2020

A new project to recycle and process rare earth metal powders could help free up the supply chain for these sought-after materials.
Network distribution of molybdenum among pure titanium powders for enhanced wear properties
Authors: Yamanoglu Ridvan
Published: January 2020

A homogeneous network distribution of molybdenum particles among pure titanium particles was successfully produced by powder metallurgy. The Ti–xMo mixtures were consolidated by uniaxial hot pressing under a 10−4 mbar vacuum atmosphere at 950 °C for 30 min. The distribution of the molybdenum particles in the structure was investigated by optical and scanning electron microscopy in polished and etched conditions. The dry sliding wear properties of the Ti–xMo compacts and the Ti6Al4V alloy was carried out using a ball on disc test using a 250 m distance, 150 rpm and 20 N load. 100Cr6 steel was selected as the counterface material during the wear tests. The results showed that titanium alloy with a content of 10 wt.% Mo has the highest wear resistance within the Ti–xMo alloys. In addition, Ti–10Mo alloys showed an intensive wear resistance compared to the Ti6Al4V alloy.
Identification of contribution and lacks of the ecodesign education to the achievement of sustainability issues by analyzing the French education system
Authors: Perpignan Catherine , Robin Vincent , Baouch Yacine , Eynard Benoit
Published: January 2020

The sustainability concept is becoming ingrained in the international engineering community. The next generation of engineers has to be trained to appreciate economic, environmental, and societal impacts of its decisions, with an international perspective and at a local and global scale. The aim of this paper is to contribute to identifying the strengths and limits of current sustainability education practices to will be able to improve future decision-makers' and product designers' training. The first step of our research concerns the identification of knowledge, skills, attitudes, and values associated with sustainability and ecodesign to highlight what kind of engineers' competencies for sustainability have to be trained. Based on this identification, we examine the French education system from secondary school to university to study sustainability and ecodesign integration in different technological French curricula and practices. The objective is to estimate the effective place of sustainable development and ecodesign in the technological training courses. We analyze programs and complete our approach by observing teachers in their classrooms or by conducting interviews. Even if concepts, knowledge and skills related to ecodesign appear in many different programs, our study emphasizes that there is not a continuum between pre-secondary school, high school, and university. As a consequence, teachers have difficulties to understand the aims and the coherence of the program, and students are not really comfortable with the issues of sustainability and ecodesign. We propose to improve programs and practices by developing multidisciplinary curricula covering most of the sustainable issues and integrating best practices of international universities.
Living in the “What Might Be”
Authors: Chappell Charles Richard
Published: January 2020

In a short period of time in the late 1950s and early 1960s two American presidents set forth challenges for our country to commit itself to space exploration, first with launching a satellite into orbit and then by putting American astronauts on the Moon and returning them safely to Earth. This leadership of Presidents Eisenhower and Kennedy sent a clear message to all Americans, particularly young people, about the importance of committing their lives to becoming space explorers. It was a clarion call to thousands to begin their personal journeys of exploration by dedicating themselves to the study of science, mathematics, and engineering. This is the story of one of these young people who, in the face of early failure, responded to the nation's call and found his self‐esteem and ultimately his entire career living in the “what might be” of the explorer's life.