bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morse Theory for S-balanced Configurations in the Newtonian n-body Problem
Authors: Asselle Luca , Portaluri Alessandro 
Published: July 2021

AbstractFor the Newtonian (gravitational) n-body problem in the Euclidean d-dimensional space, the simplest possible solutions are provided by those rigid motions (homographic solutions) in which each body moves along a Keplerian orbit and the configuration of the n-body is a (constant up to rotations and scalings) central configuration. For $$d\le 3$$

d
≤
3

, the only possible homographic motions are those given by central configurations. For $$d \ge 4$$

d
≥
4

instead, new possibilities arise due to the higher complexity of the orthogonal group $$\mathrm {O}(d)$$

O
(
d
)

, as observed by Albouy and Chenciner (Invent Math 131(1):151–184, 1998). For instance, in $$\mathbb {R}^4$$

R

4

it is possible to rotate in two mutually orthogonal planes with different angular velocities. This produces a new balance between gravitational forces and centrifugal forces providing new periodic and quasi-periodic motions. So, for $$d\ge 4$$

d
≥
4

there is a wider class of S-balanced configurations (containing the central ones) providing simple solutions of the n-body problem, which can be characterized as well through critical point theory. In this paper, we first provide a lower bound on the number of balanced (non-central) configurations in $$\mathbb {R}^d$$

R

d

, for arbitrary $$d\ge 4$$

d
≥
4

, and establish a version of the $$45^\circ $$

45
∘

-theorem for balanced configurations, thus answering some of the questions raised in Moeckel (Central configurations, 2014). Also, a careful study of the asymptotics of the coefficients of the Poincaré polynomial of the collision free configuration sphere will enable us to derive some rather unexpected qualitative consequences on the count of S-balanced configurations. In the last part of the paper, we focus on the case $$d=4$$

d
=
4

and provide a lower bound on the number of periodic and quasi-periodic motions of the gravitational n-body problem which improves a previous celebrated result of McCord (Ergodic Theory Dyn Syst 16:1059–1070, 1996).
Spectral Shape Recovery and Analysis Via Data-driven Connections
Authors: Marin Riccardo , Rampini Arianna , Castellani Umberto , Rodolà Emanuele , Ovsjanikov Maks , Melzi Simone 
Published: July 2021

AbstractWe introduce a novel learning-based method to recover shapes from their Laplacian spectra, based on establishing and exploring connections in a learned latent space. The core of our approach consists in a cycle-consistent module that maps between a learned latent space and sequences of eigenvalues. This module provides an efficient and effective link between the shape geometry, encoded in a latent vector, and its Laplacian spectrum. Our proposed data-driven approach replaces the need for ad-hoc regularizers required by prior methods, while providing more accurate results at a fraction of the computational cost. Moreover, these latent space connections enable novel applications for both analyzing and controlling the spectral properties of deformable shapes, especially in the context of a shape collection. Our learning model and the associated analysis apply without modifications across different dimensions (2D and 3D shapes alike), representations (meshes, contours and point clouds), nature of the latent space (generated by an auto-encoder or a parametric model), as well as across different shape classes, and admits arbitrary resolution of the input spectrum without affecting complexity. The increased flexibility allows us to address notoriously difficult tasks in 3D vision and geometry processing within a unified framework, including shape generation from spectrum, latent space exploration and analysis, mesh super-resolution, shape exploration, style transfer, spectrum estimation for point clouds, segmentation transfer and non-rigid shape matching.
Slowing down as we age: aging of the cardiac pacemaker’s neural control
Authors: Choi Sabrina , Baudot Matthias , Vivas Oscar , Moreno Claudia M. 
Published: July 2021

AbstractThe cardiac pacemaker ignites and coordinates the contraction of the whole heart, uninterruptedly, throughout our entire life. Pacemaker rate is constantly tuned by the autonomous nervous system to maintain body homeostasis. Sympathetic and parasympathetic terminals act over the pacemaker cells as the accelerator and the brake pedals, increasing or reducing the firing rate of pacemaker cells to match physiological demands. Despite the remarkable reliability of this tissue, the pacemaker is not exempt from the detrimental effects of aging. Mammals experience a natural and continuous decrease in the pacemaker rate throughout the entire lifespan. Why the pacemaker rhythm slows with age is poorly understood. Neural control of the pacemaker is remodeled from birth to adulthood, with strong evidence of age-related dysfunction that leads to a downshift of the pacemaker. Such evidence includes remodeling of pacemaker tissue architecture, alterations in the innervation, changes in the sympathetic acceleration and the parasympathetic deceleration, and alterations in the responsiveness of pacemaker cells to adrenergic and cholinergic modulation. In this review, we revisit the main evidence on the neural control of the pacemaker at the tissue and cellular level and the effects of aging on shaping this neural control.
Looking back at “our science” and “our history”: an exploration of Korean preservice science teachers’ encounters with East Asian history of science
Authors: Park Wonyong , Song Jinwoong 
Published: July 2021

AbstractDespite the long-standing interest among science educators in using history of science in science teaching, little has been discussed around whether and how non-Western histories of science could be incorporated into science education. This study considers some opportunities and challenges of addressing East Asian history of science (EAHOS) in the science teacher education context, drawing on postcolonial science studies and global history of science. Eight undergraduate preservice science teachers (PSTs) participated in sessions on EAHOS. Our aim was to investigate the PSTs’ perceptions relating to the nature of EAHOS and its relevance to science teaching. Using interviews and reflective essays, we explore the tension coming from their dual positions as science teachers and East Asian people as they entered into the unfamiliar territory of EAHOS. When they were considering themselves specifically as science teachers, they tended to focus on the aspects of EAHOS as knowledge and concluded that it has little to do with achieving the aims of science teaching because is not part of modern science. On the contrary, when they were talking about their roles as teachers in general, they were able to come up with several educational benefits that EAHOS can offer to students, particularly in its relation to worldview and history. Additionally, several mixed feelings were expressed about the way EAHOS is often portrayed as “our” history about “our” science. Overall, the experience of exploring and discussing EAHOS provided the PSTs with an opportunity to critically reflect on science education and their responsibility as teachers in the context of broader society and culture.
Archetypes of Driver Combinations Leading to Foreign Market Exit: An Investigation into European Grocery Retailing
Authors: Schmid David , de Thomas Wagner Finn , Morschett Dirk 
Published: July 2021

AbstractExisting research into retailers’ foreign market exits has uncovered a number of drivers that lead multinational retailers to divest from certain countries. While scholars have investigated these drivers in isolation from one another, combinations of drivers that affect divestment decisions simultaneously remain under-researched despite scholars having indicated their importance and having called for a detailed, more holistic analysis. In this study, using a case study approach and qualitative content analysis of a wide variety of publicly available contemporary documents from different perspectives and experts, we investigate the drivers leading to all 32 country exits of the 50 largest grocery retailers in Europe in the 5-year period between 2014 and 2018. In line with previous research, the study shows the most frequent exit drivers are a low performance of the subsidiary, a low performance of the parent company, and a strategic refocus of the parent company. However, we demonstrate that for most exits, combinations of multiple interrelated drivers at the subsidiary level, the host-country level, and the parent level have a joint influence on retailers’ decisions to exit foreign markets. We also show that exits often include both failure-related drivers and strategy-related drivers. Furthermore, using the configurational approach, we identify exemplary combinations of market exit drivers that occur frequently and propose five archetypes of such combinations that suffice to explain all market exits in the dataset. For future research, we propose extending our typology through the application of a similar approach to different contexts and to use quantitative research based on the qualitative findings to generate more generalizable results.
Using citizen science data to monitor the Sustainable Development Goals: a bottom-up analysis
Authors: Ballerini Laura , Bergh Sylvia I. 
Published: July 2021

AbstractOfficial data are not sufficient for monitoring the United Nations Sustainable Development Goals (SDGs): they do not reach remote locations or marginalized populations and can be manipulated by governments. Citizen science data (CSD), defined as data that citizens voluntarily gather by employing a wide range of technologies and methodologies, could help to tackle these problems and ultimately improve SDG monitoring. However, the link between CSD and the SDGs is still understudied. This article aims to develop an empirical understanding of the CSD-SDG link by focusing on the perspective of projects which employ CSD. Specifically, the article presents primary and secondary qualitative data collected on 30 of these projects and an explorative comparative case study analysis. It finds that projects which use CSD recognize that the SDGs can provide a valuable framework and legitimacy, as well as attract funding, visibility, and partnerships. But, at the same time, the article reveals that these projects also encounter several barriers with respect to the SDGs: a widespread lack of knowledge of the goals, combined with frustration and political resistance towards the UN, may deter these projects from contributing their data to the SDG monitoring apparatus.
New examples of subsets of c with the FPP and stability of the FPP in hyperconvex spaces
Authors: Espínola-García Rafael , Japón María , Souza Daniel 
Published: July 2021

AbstractThe purpose of this work is two-fold. On the one side, we focus on the space of real convergent sequences c where we study non-weakly compact sets with the fixed point property. Our approach brings a positive answer to a recent question raised by Gallagher et al. in (J Math Anal Appl 431(1):471–481, 2015). On the other side, we introduce a new metric structure closely related to the notion of relative uniform normal structure, for which we show that it implies the fixed point property under adequate conditions. This will provide some stability fixed point results in the context of hyperconvex metric spaces. As a particular case, we will prove that the set $$M=[-1,1]^\mathbb {N}$$

M
=

[
-
1
,
1
]

N

has the fixed point property for d-nonexpansive mappings where $$d(\cdot ,\cdot )$$

d
(
·
,
·
)

is a metric verifying certain restrictions. Applications to some Nakano-type norms are also given.
Crowdsourcing and open innovation: a systematic literature review, an integrated framework and a research agenda
Authors: Cricelli Livio , Grimaldi Michele , Vermicelli Silvia 
Published: July 2021

AbstractIn recent years, Open Innovation (OI) and crowdsourcing have been very popular topics in the innovation management literature, attracting significant interest and attention, and inspiring a rich production of publications. Although these two topics share common themes and address similar managerial challenges, to the best of our knowledge, there is no systematic literature review that digs deep into the intersection of both fields. To fill in this gap a joint review of crowdsourcing and OI topics is both timely and of interest. Therefore, the main objective of this study is to carry out a comprehensive, systematic, and objective review of academic research to help shed light on the relationship between OI and crowdsourcing. For this purpose, we reviewed the literature published on these two topics between 2008 and 2019, applying two bibliometric techniques, co-citation and co-word analysis. We obtained the following results: (i) we provide a qualitative analysis of the emerging and trending themes, (ii) we discuss a characterization of the intersection between OI and crowdsourcing, identifying four dimensions (strategic, managerial, behavioral, and technological), (iii) we present a schematic reconceptualization of the thematic clusters, proposing an integrated view. We conclude by suggesting promising opportunities for future research.
On functorial (co)localization of algebras and modules over operads
Authors: Gutiérrez Javier J. , Röndigs Oliver , Spitzweck Markus , Østvær Paul Arne 
Published: July 2021

AbstractMotivated by calculations of motivic homotopy groups, we give widely attained conditions under which operadic algebras and modules thereof are preserved under (co)localization functors.
Chronic Exposure to Hypoxia Inhibits Myelinogenesis and Causes Motor Coordination Deficits in Adult Mice
Authors: Chen Lin , Ren Shu-Yu , Li Rui-Xue , Liu Kun , Chen Jing-Fei , Yang Yu-Jian , Deng Yong-Bin , Wang Han-Zhi , Xiao Lan , Mei Feng , Wang Fei 
Published: July 2021

AbstractExposure to chronic hypoxia is considered to be a risk factor for deficits in brain function in adults, but the underlying mechanisms remain largely unknown. Since active myelinogenesis persists in the adult central nervous system, here we aimed to investigate the impact of chronic hypoxia on myelination and the related functional consequences in adult mice. Using a transgenic approach to label newly-generated myelin sheaths (NG2-CreERTM; Tau-mGFP), we found that myelinogenesis was highly active in most brain regions, such as the motor cortex and corpus callosum. After exposure to hypoxia (10% oxygen) 12 h per day for 4 weeks, myelinogenesis was largely inhibited in the 4-month old brain and the mice displayed motor coordination deficits revealed by the beam-walking test. To determine the relationship between the inhibited myelination and functional impairment, we induced oligodendroglia-specific deletion of the transcription factor Olig2 by tamoxifen (NG2-CreERTM; Tau-mGFP; Olig2 fl/fl) in adult mice to mimic the decreased myelinogenesis caused by hypoxia. The deletion of Olig2 inhibited myelinogenesis and consequently impaired motor coordination, suggesting that myelinogenesis is required for motor function in adult mice. To understand whether enhancing myelination could protect brain functions against hypoxia, we treated hypoxic mice with the myelination-enhancing drug-clemastine, which resulted in enhanced myelogenesis and improved motor coordination. Taken together, our data indicate that chronic hypoxia inhibits myelinogenesis and causes functional deficits in the brain and that enhancing myelinogenesis protects brain functions against hypoxia-related deficits.
Characterizing HIV discussions and engagement on Twitter
Authors: Malik Aqdas , Antonino Angi , Khan M Laeeq , Nieminen Marko 
Published: July 2021

AbstractThe novel settings provided by social media facilitate users to seek and share information on a wide array of subjects, including healthcare and wellness. Analyzing health-related opinions and discussions on these platforms complement traditional public health surveillance systems to support timely and effective interventions. This study aims to characterize the HIV-related conversations on Twitter by identifying the prevalent topics and the key events and actors involved in these discussions. Through Twitter API, we collected tweets containing the hashtag #HIV for a one-year period. After pre-processing the collected data, we conducted engagement analysis, temporal analysis, and topic modeling algorithm on the analytical sample (n = 122,807). Tweets by HIV/AIDS/LGBTQ activists and physicians received the highest level of engagement. An upsurge in tweet volume and engagement was observed during global and local events such as World Aids Day and HIV/AIDS awareness and testing days for trans-genders, blacks, women, and the aged population. Eight topics were identified that include “stigma”, “prevention”, “epidemic in the developing countries”, “World Aids Day”, “treatment”, “events”, “PrEP”, and “testing”. Social media discussions offer a nuanced understanding of public opinions, beliefs, and sentiments about numerous health-related issues. The current study reports various dimensions of HIV-related posts on Twitter. Based on the findings, public health agencies and pertinent entities need to proactively use Twitter and other social media by engaging the public through involving influencers. The undertaken methodological choices may be applied to further assess HIV discourse on other popular social media platforms.
Mindfulness Versus Cognitive Reappraisal: the Impact of Mindfulness-Based Stress Reduction (MBSR) on the Early and Late Brain Potential Markers of Emotion Regulation
Authors: Kaunhoven Rebekah Jane , Dorjee Dusana 
Published: July 2021

Abstract
Objectives
A positive association between trait mindfulness and cognitive reappraisal has previously been found. Using event-related potentials (ERPs), we investigated the impact of an 8-week MBSR course on early and late stages of emotion regulation using mindfulness and reappraisal.

Methods
Participants were allocated into an 8-week MBSR training group (n = 14 for task reports and self-reports; n = 10 for ERPs) or a wait-list control group (n = 15 for task reports and self-reports; n = 11 for ERPs). Pre and post the 8-week training, participants completed an affective picture viewing task and were instructed to regulate their responses to negative and neutral images using mindfulness, cognitive reappraisal and expressive suppression.

Results
At post-test, only the training group showed significant improvements in self-reported trait mindfulness and trait cognitive reappraisal, together with improvements in the self-reported ability to employ mindfulness and cognitive reappraisal during the task. The training group showed decreased 200–280 ms positivity across all three strategies at post-test. The LPP did not change over time but overall showed more positive mean amplitudes to cognitive appraisal.

Conclusions
These findings suggest that MBSR may adaptively modulate early attention deployment to emotional stimuli, but modulations of later stages of emotion processing may require more extensive mindfulness training. In addition, conscious employment of mindfulness may require less cognitive effort than cognitive reappraisal.
Improving team performance prediction in MMOGs with temporal communication networks
Authors: Ghawi Raji , Müller Siegfried , Pfeffer Jürgen 
Published: July 2021

AbstractVirtual teams are becoming increasingly important. Since they are digital in nature, their “trace data” enable a broad set of new research opportunities. Online Games are especially useful for studying social behavior patterns of collaborative teams. In our study, we used longitudinal data from the massively multiplayer online game Travian collected over a 12-month period that included 4753 teams with 18,056 individuals and their communication networks. For predicting team performance, we selected several social network analysis-based attributes frequently used in team and leadership research. We find that using these features, the accuracy of predicting the team performance, in terms of $$R^2$$

R
2

, is about 60%; whereas the accuracy of classifying the top-performing teams exceeds 95%. Moreover, we examine the ability to predict the team performance based on historic data of the network features, i.e., before several weeks. We find that the best accuracy can be achieved using the features in the present and the past, as well as the past performance. For a delay of one week, the accuracy of this model is about $$R^2$$

R
2

= 97%.
Increasing risks for emerging infectious diseases within a rapidly changing High Asia
Authors: Mishra Charudutt , Samelius Gustaf , Khanyari Munib , Srinivas Prashanth Nuggehalli , Low Matthew , Esson Carol , Venkatachalam Suri , Johansson Örjan 
Published: July 2021

AbstractThe cold and arid mountains and plateaus of High Asia, inhabited by a relatively sparse human population, a high density of livestock, and wildlife such as the iconic snow leopard Panthera uncia, are usually considered low risk for disease outbreaks. However, based on current knowledge about drivers of disease emergence, we show that High Asia is rapidly developing conditions that favor increased emergence of infectious diseases and zoonoses. This is because of the existing prevalence of potentially serious pathogens in the system; intensifying environmental degradation; rapid changes in local ecological, socio-ecological, and socio-economic factors; and global risk intensifiers such as climate change and globalization. To better understand and manage the risks posed by diseases to humans, livestock, and wildlife, there is an urgent need for establishing a disease surveillance system and improving human and animal health care. Public health must be integrated with conservation programs, more ecologically sustainable development efforts and long-term disease surveillance.