bluuebunny/crossref_metadata_2025_split huggingface dataset:
Macrophage network dynamics depend on haptokinesis for optimal local surveillance
Authors: Paterson Neil , Lämmermann Tim 
Published: November 2021

SummaryMacrophages are key immune cells with important roles for tissue surveillance in almost all mammalian organs. Cellular networks made up of many individual macrophages allow for optimal removal of dead cell material and pathogens in tissues. However, the critical determinants that underlie these population responses have not been systematically studied. Here, we investigated how cell shape and the motility of individual cells influences macrophage network responses in 3D culture settings and in mouse tissues. We show that surveying macrophage populations can tolerate lowered actomyosin contractility, but cannot easily compensate for a lack of integrin-mediated adhesion. Although integrins were dispensable for macrophage chemotactic responses, they were crucial to control cell movement and protrusiveness for optimal surveillance by a macrophage population. Our study reveals that β1 integrins are important for maintaining macrophage shape and network sampling efficiency in mammalian tissues, and sets macrophage motility strategies apart from the integrin-independent 3D migration modes of many other immune cell subsets.
Laser Ablation and Fluid Flows Show a Single Force Mechanism Governs Spindle Positioning
Authors: Wu Hai-Yin , Kabacaoğlu Gökberk , Nazockdast Ehssan , Chang Huan-Cheng , Shelley Michael J. , Needleman Daniel J. 
Published: November 2021

ABSTRACTFew techniques are available for elucidating the nature of forces that drive subcellular behaviors. Here we develop two complementary ones: 1) femtosecond stereotactic laser ablation (FESLA), which rapidly creates complex cuts of subcellular structures, thereby allowing precise dissection of when, where, and in what direction forces are generated; and 2) assessment of subcellular fluid flows, by comparing direct flow measurements, using microinjected fluorescent nanodiamonds, to large-scale fluid-structure simulations of different models of force transduction. We apply these to study centrosomes in Caenorhabditis elegans early embryos, and use the data to construct a biophysically-based model of centrosome dynamics. Taken together, we demonstrate that cortical pulling forces provide a general explanation for many behaviors mediated by centrosomes, including pronuclear migration/centration and rotation, metaphase spindle positioning, asymmetric spindle elongation and spindle oscillations. In sum, this work establishes new methodologies for disentangling the forces responsible for cell biological phenomena.
Zinc finger protein Zfp335 controls early T cell development and survival through β-selection-dependent and -independent mechanisms
Authors: Wang Xin , Jiao Anjun , Sun Lina , Li Wenhua , Yang Biao , Su Yanhong , Ding Renyi , Zhang Cangang , Liu Haiyan , Yang Xiaofeng , Sun Chenming , Zhang Baojun 
Published: November 2021

AbstractT cell development in the thymus undergoes the process of differentiation, selective proliferation and survival from CD4-CD8-double negative (DN) stage to CD4+CD8+double positive (DP) stage prior to the formation of CD4+helper and CD8+cytolytic T cells ready for circulation. Each developmental stage is tightly regulated by sequentially-operating molecular networks, of which only limited numbers of transcription regulators have been deciphered. Here we identified Zfp335 transcription factor as a new player in the regulatory network controlling thymocyte development. We demonstrate that Zfp335 intrinsically controls DN to DP transition, as T cell-specific deficiency in Zfp335 leads to a substantial accumulation of DN3 along with reduction of DP, CD4+and CD8+thymocytes. This developmental blockade at DN stage results from the impaired intracellular TCRβ expression as well as increased susceptibility to apoptosis in thymocytes. Transcriptomic and ChIP-seq analyses revealed a direct regulation of transcription factors Bcl6 and Rorc by Zfp335. Importantly, enhanced expression of TCRβ and Bcl6/RorγT restores the developmental defect during DN3 to DN4 transition and improves thymocytes survival, respectively. These findings identify a critical role of Zfp335 in controlling T cell development by maintaining intracellular TCRβ expression-mediated β- selection and independently activating cell survival signaling.
Heterosis of Fitness and Phenotypic Variance in the Evolution of Diploid Gene Regulatory Network
Authors: Okubo Kenji , Kaneko Kunihiko 
Published: November 2021

Heterosis describes the phenomenon whereby a hybrid population has higher fitness than an inbred population, and has previously been explained by either Mendelian dominance or overdominance, where it is generally assumed that one gene controls one trait. How-ever, recent studies have demonstrated that genes interact through a complex gene regulatory network (GRN). Furthermore, phenotypic variance due to noise is reportedly lower for heterozygotes, whereas the origin of such variance-related heterosis remains elusive. There-fore, a theoretical analysis linking heterosis to GRN evolution and stochastic gene expression dynamics is required. Here, we investigate heterosis related to fitness and phenotypic variance in a system with interacting genes, by numerically evolving diploid GRNs. According to the results, the heterozygote population exhibited higher fitness than the homozygote population, that is, fitness-related heterosis resulting from evolution. In addition, the heterozygote population expressed lower noise-related phenotypic variance in expression levels than the homozygous population, implying that the heterozygote population is more robust to noise. Furthermore, the distribution of the ratio of heterozygote phenotypic variance to homozygote phenotypic variance exhibited quantitative agreement with previous experimental results. By applying dominance and over-dominance to the gene expression pattern rather than only a single gene expression, we confirmed the correlation between heterosis and overdominance. We explain our results by proposing that the convex high-fitness region is evolutionarily shaped in the genetic space to gain noise robustness under genetic mixing through sexual reproduction.Significance StatementHeterosis, that is higher fitness in hybrid populations than inbred populations, is a long-standing problem in genetics, evolution, and breeding studies. Heterosis is not necessarily the result of a trait uniquely determined by a single gene, but likely involves stochasticity and interactions among genes. Through numerical evolution of the gene regulatory network, we demonstrate that heterosis is shaped by evolution to achieve robustness against noise and genetic mixing by sexual recombination in gene expression dynamics. That is, a mixed population is more robust to noise than inbred populations, as revealed experimentally by reduced phenotypic variance. The observed link between heterosis and phenotypic robustness, Mendelian dominance, and the convex single-humped fitness landscape represents a novel avenue in evolution and genetics research.
Activity-dependent circuitry plasticity via the regulation of the histamine receptor level in the Drosophila visual system
Authors: Bai Yiming , Suzuki Takashi 
Published: November 2021

AbstractActivity-dependent synaptic plasticity is crucial for responses to the environment. Although the plasticity mechanisms of presynaptic photoreceptor neurons in the Drosophila visual system have been well studied, postsynaptic modifications remain elusive. In addition, further studies on the adaption of the visual system to different light experiences at a circuitry scale are required. Using the modified transcriptional reporter of intracellular Ca2+ method, we describe a way to visualize circuitry changes according to different light experiences. We found enhanced postsynaptic neuronal activity responses in lamina monopolar neuron L2 after prolonged light treatment. Although L1 also has connections with photoreceptors, there were no enhanced activity responses in L1. We also report in this study that activity-dependent transcriptional downregulation of inhibitory histamine receptors (HRs) occurs in postsynaptic neuron L2, but not in L1, during continuous light conditions. We expressed exogenous HR proteins in L2 neurons and found that it attenuated the enhanced activity response caused by constant light exposure. These findings, together with the fact that histamine is the main inhibitory neurotransmitter released by photoreceptors in the Drosophila visual system, confirmed our hypothesis that the activity-dependent transcriptional downregulation of HRs is responsible for the constant light exposure-induced circuitry response changes in L2. The results successfully demonstrated the selective circuit change after synaptic remodeling evoked by long-term activation and provided in vivo evidence of circuitry plasticity upon long-term environmental stimulation.
The different brain areas occupied for integrating information of hierarchical linguistic units: a study based on EEG and TMS
Authors: Pei Changfu , Qiu Yuan , Li Fali , Huang Xunan , Si Yajing , Li Yuqin , Zhang Xiabing , Chen Chunli , Liu Qiang , Cao Zehong , Ding Nai , Gao Shan , Alho Kimmo , Yao Dezhong , Xu Peng 
Published: November 2021

AbstractHuman linguistic units are hierarchical, and our brain responds differently when processing linguistic units during sentence comprehension, especially when the modality of the received signal is different (auditory, visual, or audio-visual). However, it is unclear how the brain processes and integrates language information at different linguistic units (words, phrases, and sentences) provided simultaneously in audio and visual modalities. To address the issue, we presented participants with sequences of short Chinese sentences through auditory or visual or combined audio- visual modalities, while electroencephalographic responses were recorded. With a frequency tagging approach, we analyzed the neural representations of basic linguistic units (i.e., characters/monosyllabic words) and higher-level linguistic structures (i.e., phrases and sentences) across the three modalities separately. We found that audio-visual integration occurs at all linguistic units, and the brain areas involved in the integration varied across different linguistic levels. In particular, the integration of sentences activated the local left prefrontal area. Therefore, we used continuous theta-burst stimulation (cTBS) to verify that the left prefrontal cortex plays a vital role in the audio-visual integration of sentence information. Our findings suggest the advantage of bimodal language comprehension at hierarchical stages in language-related information processing and provide evidence for the causal role of the left prefrontal regions in processing information of audio-visual sentences.
Social learning for enhancing social-ecological resilience to disaster-shocks: a policy Delphi approach
Authors: Haque C. Emdad , Berkes Fikret , Fernández-Llamazares Álvaro , Ross Helen , Chapin III F. Stuart , Doberstein Brent , Reed Maureen G. , Agrawal Nirupama , Nayak Prateep K. , Etkin David , Doré Michel , Hutton David 
Published: November 2021

PurposeThe plethora of contributions to social learning has resulted in a wide range of interpretations, meanings and applications of social learning, both within and across disciplines. However, advancing the concept and using social learning methods and tools in areas like disaster-shocks requires interdisciplinary consolidation of understandings. In this context, the primary focus of this paper is on the contributions of social learning to disaster risk reduction (DRR).Design/methodology/approachBy applying a three-round policy Delphi process involving 18 purposefully selected scholars and expert-practitioners, the authors collected data on the meanings of social learning for two groups of professionals, DRR and social-ecological resilience. The survey instruments included questions relating to the identification of the core elements of social learning and the prospects for enhancing social-ecological resilience.FindingsThe results revealed strong agreement that (1) the core elements of social learning indicate a collective, iterative and collaborative process that involves sharing/networking, changes in attitudes and knowledge and inclusivity; (2) social learning from disasters is unique; and (3) linkages between disciplines can be built by promoting interdisciplinarity, networks and knowledge platforms; collaboration and coordination at all levels; and teaching and practicing trust and respect. Social learning is useful in preparing for and responding to specific disaster events through communication; sharing experience, ideas and resources; creating synergies for collective action and promoting resilience.Research limitations/implicationsThe policy Delphi process involved a limited number of participants to control the quality of the data. To the best of the authors’ knowledge, this paper is the first of its kind to identify the core elements of social learning, specifically, in the disaster-shock context. It also makes significant contributions to the interdisciplinary integration issues.Practical implicationsThe practical implications of this study are related to pre-disaster planning and mitigation through the application of social learning on disaster-shocks.Social implicationsThe social implications of this study are related to valuing social learning for the improvement of disaster planning, management, and policy formulation and implementation in reducing disaster risks.Originality/valueThe study provides a consensus view on the core elements of social learning and its role in DRR and resilience building. Relevant to all stages of DRR, social learning is best characterized as a collective, iterative and collaborative process. It can be promoted by enhancing networking and interdisciplinarity.
From service-dominant orientation to positive customer outcomes: a self-determination model in the custom travel service context
Authors: Li Mingfei , Huang Shanshan , Deng Aimin , Bai Billy , Zhou Shoujiang 
Published: November 2021

Purpose
Drawing on self-determination theory and insights from the literature on service-dominant (S-D) logic and value co-creation, this paper aims to investigate the impacts of an S-D orientation on positive customer outcomes (i.e. customer participation behaviors, customer citizenship behaviors and quality of life) and the underlying mechanisms of these effects.

Design/methodology/approach
Custom travel service (CTS) was chosen as the research setting. In total, 303 valid questionnaires were gathered from tourists in China. The partial least squares structural equation modeling approach was used for model estimation.

Findings
Tourism firms’ S-D orientation positively influences customer participation behaviors via customer psychological need satisfaction (i.e. perceived autonomy, competence and relatedness), customer citizenship behaviors via perceived relatedness and customer quality of life via perceived autonomy and perceived competence.

Research limitations/implications
Although the impact of S-D orientation is studied in the CTS context, this study illustrates how firms embracing S-D logic can facilitate value co-creation and customer quality of life, presenting a more precise picture for academics and practitioners.

Originality/value
This paper is the first attempt to empirically examine the relationships among S-D orientation, customer value cocreation and quality of life. The relevance of customer psychological need satisfaction is acknowledged in this study.
Who is an evangelist? Food tourists’ positive and negative eWOM behavior
Authors: Kim Jin-young , Hwang Johye 
Published: November 2021

PurposeThis study aims to examine food tourists’ engagement in positive and negative electronic word-of-mouth (eWOM) by considering the following questions: Do satisfied customers engage in advocacy, and do dissatisfied customers make the same effort to spread their negative experiences? Which restaurant experience attributes influence eWOM behavior? What demographic and psychographic characteristics contribute to advocacy?Design/methodology/approachUsing data from an online survey of 456 consumers with restaurant experience in the tourism context, this study applied simultaneous Tobit estimation to examine the research hypotheses.FindingsEngagement in negative eWOM because of poor experiences was stronger than engagement in positive eWOM because of positive experiences. Food taste was a critical attribute for both positive and negative eWOM. Authenticity was influential for positive eWOM only, and value was influential for negative eWOM only. Atmosphere, service and location were found to be insignificant, indicating that they are ‘indifferent’ factors for eWOM in the food tourism context. Female customers were more active in negative advocacy, while Generation Y customers were more active in positive advocacy. Food involvement was significantly related to both positive and negative eWOM.Research limitations/implicationsThe results of this study provide useful marketing and service insights for restaurant managers in the digitally connected world, enabling them to formulate services based on factors critical for restaurant eWOM in the tourism context.Originality/valueTo fill a gap in the current literature in the era of digital marketing, this study takes a comprehensive yet industry-specific perspective on eWOM engagement by examining demographic factors and the food involvement of consumers as well as restaurant experience attributes. By investigating both positive and negative eWOM, this study presents meaningful practical and theoretical implications.
Active disturbance rejection motion control of spherical robot with parameter tuning
Authors: Liu Manlu , Lin Rui , Yang Maotao , Nazarova Anaid V. , Huo Jianwen 
Published: November 2021

Purpose
The characteristics of spherical robots, such as under-drive, non-holonomic constraints and strong coupling, make it difficult to establish its motion control model accurately. To improve the anti-interference performance of spherical robots in practical engineering, this paper proposes a spherical robot motion controller based on auto-disturbance rejection control (ADRC) with parameter tuning.

Design/methodology/approach
This paper considers the influences of the spherical shell, internal frame and pendulum on the movement of the spherical robot during the rotation to establish the multi-body dynamics model of the XK-I spherical robot. Due to the serious coupling problem of the dynamic model, the motion control state equation is constructed using linearization and decoupling. The XK-I spherical robot PSO-ADRC motion controller with parameter tuning function is designed by combining the state equation with the particle swarm optimization (PSO) algorithm. Finally, experiments are performed to evaluate the feasibility of PSO-ADRC in an actual case compared to ADRC, PSO-PID and PID.

Findings
By analyzing the required time to reach the expected value, the control stability and the fluctuation range of the standard deviation after reaching the expected value, the superiority of PSO-ADRC to ADRC, PSO-PID and PID is demonstrated in terms of the speed and anti-interference ability.

Practical implications
The proposed method can be applied to the robot control field.

Originality/value
A parameter-tuning method for auto-disturbance-rejection motion control of the spherical robot is proposed. According to the experimental results, the anti-interference ability of the spherical robot moving on uneven ground is improved. Therefore, it provides a foundation for the autonomous environmental monitoring of the spherical robot equipped with sensors.
Club convergence of crime rates in the United States of America
Authors: Ogundari Kolawole 
Published: November 2021

Purpose
The cyclical behavior of US crime rates reflects the dynamics of crime in the country. This paper aims to investigate the US's club convergence of crime rates to provide insights into whether the crime rates increased or decreased over time. The paper also analyzes the factors influencing the probability of states converging to a particular convergence club of crime.

Design/methodology/approach
The analysis is based on balanced panel data from all 50 states and the district of Columbia on violent and property crime rates covering 1976–2019. This yields a cross-state panel of 2,244 observations with 55 time periods and 51 groups. In addition, the author used a club clustering procedure to investigate the convergence hypothesis in the study.

Findings
The empirical results support population convergence of violent crime rates. However, the evidence that supports population convergence of property crime rates in the study is not found. Further analysis using the club clustering procedure shows that property crime rates converge into three clubs. The existence of club convergence in property crime rates means that the variation in the property crime rates tends to narrow among the states within each of the clubs identified in the study. Analysis based on an ordered probit model identifies economic, geographic and human capital factors that significantly drive the state's convergence club membership.

Practical implications
The central policy insight from these results is that crime rates grow slowly over time, as evident by the convergence of violent crime and club convergence of property crime in the study. Moreover, the existence of club convergence of property crime is an indication that policies to mitigate property crime might need to target states within each club. This includes the efforts to use state rather than national crime-fighting policies.

Social implications
As crimes are committed at the local level, this study's primary limitation is the lack of community-level data on crime and other factors considered. Analysis based on community-level data might provide a better representation of crime dynamics. However, the author hopes to consider this as less aggregated data are available to use in future research.

Originality/value
The paper provides new insights into the convergence of crime rates using the club convergence procedure in the USA. This is considered an improvement to the methods used in the previous studies.