bluuebunny/crossref_metadata_2025 huggingface dataset:
Patterns of brain degeneration in early-stage relapsing-remitting multiple sclerosis
Authors: Meijboom Rozanna , York Elizabeth N , Kampaite Agniete , Harris Mathew A , White Nicole , Valdés Hernández Maria del C , Thrippleton Michael J , Connick Peter , Hunt David , Chandran Siddharthan , Waldman Adam D
Published: November 2021

Recurrent neuroinflammation in relapsing-remitting MS (RRMS) is thought to lead to neurodegeneration, resulting in progressive disability. Repeated magnetic resonance imaging (MRI) of the brain provides non-invasive measures of atrophy over time, a key marker of neurodegeneration. This study investigates regional neurodegeneration of the brain in early-stage RRMS using volumetry and voxel-based morphometry (VBM).

RRMS patients (N=354) underwent 3T structural MRI at diagnosis and 1-year follow-up, as part of the Scottish multicentre ‘FutureMS’ study. MRI data were processed using FreeSurfer to derive volumetrics, and FSL for VBM (grey matter (GM) only), to establish patterns of change in GM and normal-appearing white matter (NAWM) over time throughout the cerebrum, cerebellum and brainstem.

Volumetric analyses showed a decrease over time (q<0.05) in bilateral cortical GM and NAWM, multiple subcortical structures, cerebellar GM and the brainstem. Additionally, NAWM and GM volume decreased respectively in the following cortical regions, frontal: 14 out of 28 regions and 17/28; temporal: 18/18 and 15/18; parietal: 14/14 and 11/14; occipital: 7/8 and 8/8. Left GM and NAWM asymmetry was observed in the frontal lobe. GM VBM analysis showed three major clusters of decrease over time: 1) temporal lobe and subcortical areas, 2) cerebellum, 3) anterior cingulum and supplementary motor cortex; and four smaller clusters within the occipital lobe.

Widespread neurodegeneration was observed in early-stage RRMS; particularly in the brainstem, cerebellar GM, and subcortical and occipital-temporal regions. Volumetric and VBM results emphasise different as well as overlapping patterns of longitudinal change, and provide potential response markers for existing therapies and trials of neuroprotective agents.
Missing genetic links between general factors of brain resting-state functional magnetic resonance imaging, cognition and psychopathology
Authors: Guimaraes JPOFT , Franke B , Beckmann CF , Bralten J , Sprooten E
Published: November 2021

General factors capturing the shared genetics in psychiatric (genomic p-factor) and cognitive traits (genomic g-factor), and more recently in resting-state functional magnetic resonance imaging-derived brain networks, have contributed to our increased understanding of the etiologies in their respective domains. Yet it remains unclear whether general factors can capture the three-way genetic overlap of psychopathology, cognition and brain function. Here we tested for the presence of this genetic overlap via genetic correlation analyses using summary statistics of genome-wide association studies of the p-factor (N = 162,151 cases and 276,846 controls), the g-factor (N = 269,867), and the two genomic factors estimated from the amplitude in resting-state functional magnetic resonance imaging-derived brain networks (N = 31,688). Unlike hypothesized, only the genetic correlation between the p-factor and the g-factor was significant. We conclude that specific functional brain network constructs may have more potential than their derived general dimensions to capture relevant genetic variation for cognition and psychopathology.
Exploration of the antimicrobial synergy between selected natural substances on Streptococcus mutans to identify candidates for the control of dental caries
Authors: Prince Alisha , Roy Soumya , McDonald David
Published: November 2021

Dental caries is caused by dental plaque, a community of micro-organisms embedded in an extracellular polymer matrix as a biofilm on the tooth surface. Natural products that are widely available could be used as an alternative or adjunctive anti-caries therapy. Sometimes, when two products are used together, they yield a more powerful antimicrobial effect than the anticipated additive effect. These synergistic combinations are often better treatment options because individual agents may not have sufficient antimicrobial action to be effective when used alone. Cranberries contain phenolic compounds like proanthocyanidins (PAC) that disrupt biofilm formation. Manuka honey has high concentrations of the agent methylglyoxal, which is cariostatic. Because these agents have varied modes of antimicrobial action, they show potential for possible synergistic effects when paired.

Various cranberry extracts were tested pairwise with manuka honey or methylglyoxal by well-diffusion assays and 96-well checkerboard assays in the presence of Streptococcus mutans to test for synergy. Synergy was demonstrated in two of the cranberry extracts paired with manuka honey. The synergistic combinations found in this research thus can be considered as candidates for the formulation of a dentifrice that could be used to inhibit the formation of dental plaque and thereby avoid the development of caries.

Significance and Impact

The emergence of bacteria resistant to antimicrobial agents has led to a shortage of options when choosing effective treatment agents. Further, some antibiotics used at therapeutic doses can produce undesired side effects. However, by utilizing synergistic combinations of antimicrobial agents, the desired antimicrobial effects can often be produced without subjecting the patient to toxic or irritating doses of individual agents. Streptococcus mutans growth and biofilm formation is a major contributor towards dental caries. In this study, a synergistic combination of Manuka honey and cranberry extracts gives evidence that it can be used as an alternative or adjunctive anti-caries therapy.
A structured scaffold underlies activity in the hippocampus
Authors: Mulders Dounia , Yim Man Yi , Lee Jae Sung , Lee Albert K. , Taillefumier Thibaud , Fiete Ila R.
Published: November 2021

Place cells are believed to organize memory across space and time, inspiring the idea of the cognitive map. Yet unlike the structured activity in the associated grid and head-direction cells, they remain an enigma: their responses have been difficult to predict and are complex enough to be statistically well-described by a random process. Here we report one step toward the ultimate goal of understanding place cells well enough to predict their fields. Within a theoretical framework in which place fields are derived as a conjunction of external cues with internal grid cell inputs, we predict that even apparently random place cell responses should reflect the structure of their grid inputs and that this structure can be unmasked if probed in sufficiently large neural populations and large environments. To test the theory, we design experiments in long, locally featureless spaces to demonstrate that structured scaffolds undergird place cell responses. Our findings, together with other theoretical and experimental results, suggest that place cells build memories of external inputs by attaching them to a largely prespecified grid scaffold.
Large scale PVA modelling of insects in cultivated grasslands: the role of dispersal in mitigating the effects of management schedules under climate change
Authors: Leins Johannes A. , Grimm Volker , Drechsler Martin
Published: November 2021

In many species, dispersal is decisive for survival in a changing climate. Simulation models for population dynamics under climate change thus need to account for this factor. Moreover, large numbers of species inhabiting agricultural landscapes are subject to disturbances induced by human land use. We included dispersal in the HiLEG model that we previously developed to study the interaction between climate change and agricultural land use in single populations. Here, the model was parameterized for the large marsh grasshopper (LMG) in cultivated grasslands of North Germany to analyze (1) the species development and dispersal success depending on severity of climate change in sub regions, (2) the additional effect of grassland cover on dispersal success, and (3) the role of dispersal in compensating for detrimental grassland mowing. Our model simulated population dynamics in 60-year periods (2020-2079) on a fine temporal (daily) and high spatial (250 × 250 m2) scale in 107 sub regions, altogether encompassing a range of different grassland cover, climate change projections and mowing schedules. We show that climate change alone would allow the LMG to thrive and expand, while grassland cover played a minor role. Some mowing schedules that were harmful to the LMG nevertheless allowed the species to moderately expand its range. Especially under minor climate change, in many sub regions dispersal allowed for mowing early in the year, which is economically beneficial for farmers. More severe climate change could facilitate LMG expansion to uninhabited regions, but would require suitable mowing schedules along the path.

These insights can be transferred to other species, given that the LMG is considered a representative of grassland communities. For more specific predictions on the dynamics of other species affected by climate change and land use, the publicly available HiLEG model can be easily adapted to the characteristics of their life cycle.
Macrophage network dynamics depend on haptokinesis for optimal local surveillance
Authors: Paterson Neil , Lämmermann Tim
Published: November 2021

Macrophages 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

Few 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

T 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 Statement

Heterosis, 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

Activity-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

Human 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.
Intergenic ORFs as elementary structural modules of de novo gene birth and protein evolution
Authors: Papadopoulos Chris , Callebaut Isabelle , Gelly Jean-Christophe , Hatin Isabelle , Namy Olivier , Renard Maxime , Lespinet Olivier , Lopes Anne
Published: November 2021

The noncoding genome plays an important role in de novo gene birth and in the emergence of genetic novelty. Nevertheless, how noncoding sequences’ properties could promote the birth of novel genes and shape the evolution and the structural diversity of proteins remains unclear. Therefore, by combining different bioinformatic approaches, we characterized the fold potential diversity of the amino acid sequences encoded by all intergenic open reading frames (ORFs) of S. cerevisiae with the aim of (1) exploring whether the structural states’ diversity of proteomes is already present in noncoding sequences, and (2) estimating the potential of the noncoding genome to produce novel protein bricks that could either give rise to novel genes or be integrated into pre-existing proteins, thus participating in protein structure diversity and evolution. We showed that amino acid sequences encoded by most yeast intergenic ORFs contain the elementary building blocks of protein structures. Moreover, they encompass the large structural state diversity of canonical proteins, with the majority predicted as foldable. Then, we investigated the early stages of de novo gene birth by reconstructing the ancestral sequences of 70 yeast de novo genes and characterized the sequence and structural properties of intergenic ORFs with a strong translation signal. This enabled us to highlight sequence and structural factors determining de novo gene emergence. Finally, we showed a strong correlation between the fold potential of de novo proteins and one of their ancestral amino acid sequences, reflecting the relationship between the noncoding genome and the protein structure universe.
Delayed DNA replication in haploid human embryonic stem cells
Authors: Edwards Matthew M. , Zuccaro Michael V. , Sagi Ido , Ding Qiliang , Vershkov Dan , Benvenisty Nissim , Egli Dieter , Koren Amnon
Published: November 2021

Haploid human embryonic stem cells (ESCs) provide a powerful genetic system but diploidize at high rates. We hypothesized that diploidization results from aberrant DNA replication. To test this, we profiled DNA replication timing in isogenic haploid and diploid ESCs. The greatest difference was the earlier replication of the X Chromosome in haploids, consistent with the lack of X-Chromosome inactivation. We also identified 21 autosomal regions that had delayed replication in haploids, extending beyond the normal S phase and into G2/M. Haploid-delays comprised a unique set of quiescent genomic regions that are also underreplicated in polyploid placental cells. The same delays were observed in female ESCs with two active X Chromosomes, suggesting that increased X-Chromosome dosage may cause delayed autosomal replication. We propose that incomplete replication at the onset of mitosis could prevent cell division and result in re-entry into the cell cycle and whole genome duplication.
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

Purpose

The 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/approach

By 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.

Findings

The 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/implications

The 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 implications

The practical implications of this study are related to pre-disaster planning and mitigation through the application of social learning on disaster-shocks.

Social implications

The 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/value

The 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

Purpose

This 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/approach

Using 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.

Findings

Engagement 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/implications

The 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/value

To 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.
Success criteria-based impacts of risk factors on education building projects in southwestern Nigeria
Authors: Adedokun Olufisayo Adewumi , Egbelakin Temitope , Adedokun Deborah Oluwafunke , Adafin Johnson
Published: November 2021

Purpose

Despite the huge capital outlay in tertiary education building projects (TEBP), these projects undoubtedly failed in meeting the set objectives of cost, time and quality, among others. Therefore, rather than the impacts of risks on the overall project performance, which is common in the construction management literature, the purpose of this study is to assess the impacts of risk factors on the criteria for measuring the success of public TEBP.

Design/methodology/approach

The paper adopted a quantitative research method where the data collection was via a questionnaire survey. The researcher administered 452 questionnaires to the client representatives, consultants and contractors involved in building projects across five public tertiary education institutions in Ondo State, Nigeria. Of 452 questionnaires, 279 were retrieved and suitable for the analysis, translating to a 61.73% response rate. The reliability analysis of the research instrument showed 0.965 and 0.807, via Cronbach’s alpha test, indicating high reliability of the instrument used for data collection.

Findings

The study found different risk factors affecting the criteria for measuring the success of TEBP. For instance, the environmental risk factor significantly impacted completion to cost, while financial and political risk factors significantly impacted completion to time. In addition, while environmental, legal and management risks significantly impacted end-user satisfaction, safety performance was significantly impacted by logistic, legal, design, construction, political and management risks. Besides, the logistic, legal, design, construction, financial, political and management risk factors impacted profit. However, despite profit being one of the criteria for measuring the success of building projects, it recorded the highest risk impacts amounting to 41% variance.

Research limitations/implications

The findings are limited to the public tertiary education building projects procured via competitive tendering; therefore, the results might differ when considering other procurement methods.

Practical implications

The practical implication is that rather than focusing on all risk factors, the project stakeholders could give adequate attention to the significant risk factors impacting each of the parameters for measuring the success of education building projects.

Originality/value

The study revealed specific risk factors impacting the criteria for measuring the success of TEBP, which extend beyond the use of the overall project performance approach.
Consumer interpretations of fashion sustainability terminology communicated through labelling
Authors: Ritch Elaine L.
Published: November 2021

Purpose

The purpose of this research is to examine how consumers interpret and understand sustainable fashion production and how this informs their fashion consumption practice.

Design/methodology/approach

The research adopts an interpretivist approach with in-depth interviews with 28 participants. Sampling criterion sought consumers already engaged with sustainable production – professionally working mothers – to explore how their sustainability knowledge was evaluated for sustainable fashion claims. Garment labels that descripted facets of sustainable production were introduced to encourage discourse of sustainable fashion knowledge.

Findings

The findings illustrate that sustainable fashion production is not understood and efforts to apply sustainability concepts were often misunderstood which led to scepticism for higher pricing and marketing claims. Despite this, there was concern for the wider implications of sustainability.

Research limitations/implications

Limitations include the small sample from one geographical area (Edinburgh), despite the richness of the data collected.

Practical implications

The research offers practical advice for fashion marketers to educate consumers through effective communication strategies how sustainable fashion concepts improve consumer concerns surrounding fashion production.

Social implications

The research indicates increased concern for fashion sustainability, something that fashion retailers should be mindful of.

Originality/value

There has been little research examining consumer interpretation of sustainable fashion terminology, and this research adds to understanding how sustainability is evaluated within fashion production.
Moderated mediation and J-curve emergence in path models: an information systems research perspective
Authors: Kock Ned
Published: November 2021

Purpose

J-curve relationship analyses can provide valuable insights to information systems (IS) researchers. This paper aims to discuss moderated mediation in IS research and the related emergence of J-curve relationships.

Design/methodology/approach

Building on an illustrative study in the field of IS, the author Lays out three steps to combine moderation and J-curve analyses, with the goal of more fully understanding the underlying moderated mediation relationships. The paper proposes a new segmentation delta method to test for J-curve emergence, as part of this framework.

Findings

The paper shows, in the context of this study, the complementarity of moderation and J-curve analyses.

Research limitations/implications

Currently, IS researchers rarely conduct moderation and J-curve analyses in a complementary way, even though there are software tools, and related methods, which allow them to do so in a relatively straightforward way.

Originality/value

The analyses were conducted with the software WarpPLS, a widely used tool that allows for moderated mediation and J-curve analyses, in a way that is fully compatible with the set of steps presented in this paper.
Program evaluation practices and the training of PhD students in STEM
Authors: Reeves Philip M. , Claydon Jennifer , Davenport Glen A.
Published: November 2021

Purpose

Program evaluation stands as an evidence-based process that would allow institutions to document and improve the quality of graduate programs and determine how to respond to growing calls for aligning training models to economic realities. This paper aims to present the current state of evaluation in research-based doctoral programs in STEM fields.

Design/methodology/approach

To highlight the recent evaluative processes, the authors restricted the initial literature search to papers published in English between 2008 and 2019. As the authors were motivated by the shift at NIH, this review focuses on STEM programs, though papers on broader evaluation efforts were included as long as STEM-specific results could be identified. In total, 137 papers were included in the final review.

Findings

Only nine papers presented an evaluation of a full program. Instead, papers focused on evaluating individual components of a graduate program, testing small interventions or examining existing national data sets. The review did not find any documents that focused on the continual monitoring of training quality.

Originality/value

This review can serve as a resource, encourage transparency and provide motivation for faculty and administrators to gather and use assessment data to improve training models. By understanding how existing evaluations are conducted and implemented, administrators can apply evidence-based methodologies to ensure the highest quality training to best prepare students.
Recent advances in structural studies of the Legionella pneumophila Dot/Icm type IV secretion system
Authors: Kitao Tomoe , Kubori Tomoko , Nagai Hiroki
Published: November 2021

The intracellular bacterial pathogen Legionella pneumophila utilizes the Dot/Icm type IV secretion system to translocate approximately 300 effector proteins to establish a replicative niche known as the Legionella‐containing vacuole. The Dot/Icm system is classified as a type IVB secretion system, which is evolutionarily closely related to the I‐type conjugation systems and is distinct from type IVA secretion systems, such as the Agrobacterium VirB/D4 system. Although both type IVA and IVB systems directly transport nucleic acids or proteins into the cytosol of recipient cells, the components and architecture of type IVB systems are much more complex than those of type IVA systems. Taking full advantage of rapidly developing cryo‐electron microscopy techniques, the structural details of the transport apparatus and coupling complexes in the Dot/Icm system have been clarified in the past few years. In this review, we summarize recent progress in the structural studies of the L. pneumophila type IVB secretion system and the insights gained into the mechanisms of substrate recognition and transport.
The association between elevated serum interleukin‐22 and the clinical diagnosis of axial spondyloarthritis: A retrospective study
Authors: Sagiv Michal , Adawi Mohammad , Awisat Abid , Shouval Aniela , Peri Regina , Sabbah Firas , Rosner Itzhak , Kessel Aharon , Slobodin Gleb
Published: November 2021

Objective

There is an unmet need for a reliable biomarker for the differentiation of axial spondyloarthritis (AxSpA) from its mimickers. Serum levels of interleukin‐22 (IL‐22) have previously been found to be significantly elevated in patients with AxSpA compared with healthy individuals or persons with osteoarthritis.

Methods

Consecutive patients with established or suspected AxSpA were enrolled. The clinical data, as well as results of laboratory and imaging studies, were acquired from patients’ charts. The final diagnosis of definite or probable SpA, or an alternative diagnosis, was determined, and the serum levels of IL‐22 were examined by enzyme‐linked immunosorbent immunoassay.

Results

Interleukin‐22 levels were significantly higher in patients with definite AxSpA (29 patients) compared with patients with alternative diagnoses (14 patients) and healthy volunteers (16 individuals; P < 0.001 for both comparisons). The sensitivity and specificity of the serum IL‐22 for the AxSpA diagnosis were 0.68 (95% CI 0.49‐0.84) and 0.86 (95% CI 0.68‐0.95), respectively, for the cut‐off value of 5 pg/mL. In patients with AxSpA, serum IL‐22 levels did not correlate with modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS), or serum C‐reactive protein.

Conclusion

Serum IL‐22 levels are elevated in patients with the clinical diagnosis of AxSpA and can potentially serve as an independent biomarker for the differentiation of AxSpA from its non‐inflammatory mimickers.
Aspirin for the prevention of pre‐eclampsia in women with pre‐existing diabetes: Systematic review
Authors: Zen Monica , Haider Rabbia , Simmons David , Peek Michael , Nolan Christopher J. , Padmanabhan Suja , Jesudason Shilpa , Alahakoon Thushari I. , Cheung Ngai Wah , Lee Vincent W.
Published: November 2021

Background

There is a lack of evidence for pre‐eclampsia prophylaxis with aspirin in women with pre‐existing diabetes mellitus (DM).

Aims

To examine the evidence for aspirin in pre‐eclampsia prophylaxis in women with pre‐existing DM.

Material and Methods

An electronic search using Ovid MEDLINE, Embase, CinicalTrials.gov and the Cochrane CENTRAL register of controlled trials through to February 2021 was performed. Reference lists of identified studies, previous review articles, clinical practice guidelines and government reports were manually searched. Randomised controlled trials (RCTs) of aspirin vs placebo for pre‐eclampsia prophylaxis were included. Articles were manually reviewed to determine if cohorts included women with DM. The systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. Data from included trials were extracted independently by two authors who also independently assessed risk of bias as per the Cochrane Handbook criteria version 5.1.0. Data were analysed using Rev‐Man 5.4.

Results

Forty RCTs were identified, of which 11 included a confirmed subset of women with DM; however, data were insufficient for meta‐analysis. Meta‐analysis of 930 women with DM, from individual patient data included in a systematic review and unpublished data from one of the 11 RCTs, showed a non‐significant difference in the outcome of pre‐eclampsia in participants treated with aspirin compared to placebo (odds ratio 0.58; 95% CI 0.20–1.71; P = 0.33).

Conclusions

Pre‐eclampsia risk reduction with aspirin prophylaxis in women with pre‐existing DM may be similar to women without pre‐existing DM. However, randomised data within this meta‐analysis were insufficient, warranting the need for further studies within this high‐risk group of women.