bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new modulation for three‐phase current source converter
Authors: Teng Yiyina , Guo Xiaoqiang , Wei Yupeng , He Meiling , Wang Baocheng 
Published: August 2024

AbstractThis brief proposes an improved pulse width modulation (PWM) scheme, which uses diode voltage clamping characteristics to achieve the direct control of three‐phase current source converter without any logical transformation. Compared with the traditional indirect carrier modulation scheme—mapping‐PWM, the proposed scheme can solve the disadvantages of low DC current utilization, high switching loss, and complex control process. The generation mechanism of IPWM is analyzed in this brief. Then, based on the generation mechanism, the output characteristics of the system under IPWM are analyzed and compared with the traditional modulation scheme. Finally, the experimental results verify the effectiveness the proposed modulation scheme.
The link between executive skills and neural dynamics during encoding, inhibition, and retrieval of visual information in the elderly
Authors: Parviainen Tiina , Alexandrou Anna Maria , Lapinkero Hanna‐Maija , Sipilä Sarianna , Kujala Jan 
Published: August 2024

AbstractDuring aging the inter‐individual variability in both the neural and behavioral functions is likely to be emphasized. Decreased competence particularly in working memory and general executive control compromises many aspects of the quality of life also within the nonclinical population. We aimed, first, to clarify the brain basis of visual working memory and inhibition during multi‐stage natural‐like task performance, and second, to identify associations between variation in task‐related neural activity and relevant cognitive skills, namely inhibition and general working memory capacity. We recorded, using magnetoencephalography (MEG), the neural modulations associated with encoding, maintenance, and retrieval, as well as interference suppression during a visual working memory task in older adults. We quantified the neural correlates of these cognitive processes through two complementary approaches: evoked responses and oscillatory activity. Neural activity during memory retrieval and interference suppression were correlated with behavioral measures of task switching and general executive functions. Our results show that general inhibitory control induced frontocentral neural modulation across a broad range of frequencies whereas domain‐specific inhibition was limited to right posterior areas. Our findings also suggest that modulations particularly in phase‐locked evoked neural activity can be reliably associated with explicit measures of cognitive skills, with better inhibitory control linked with an early neural effect of distractor inhibition during retrieval. In general, we show that exploiting the inherent inter‐individual variability in neural measures and behavioral markers of cognition in aging populations can help establish reliable links between specific brain functions and their behavioral manifestations.
Brain mechanisms discriminating enactive mental simulations of running and plogging
Authors: Philips Roxane , Baeken Chris , Billieux Joël , Harris James Madog , Maurage Pierre , Muela Ismael , Öz İrem Tuğçe , Pabst Arthur , Sescousse Guillaume , Vögele Claus , Brevers Damien 
Published: August 2024

AbstractEnactive cognition emphasizes co‐constructive roles of humans and their environment in shaping cognitive processes. It is specifically engaged in the mental simulation of behaviors, enhancing the connection between perception and action. Here we investigated the core network of brain regions involved in enactive cognition as applied to mental simulations of physical exercise. We used a neuroimaging paradigm in which participants (N = 103) were required to project themselves running or plogging (running while picking‐up litter) along an image‐guided naturalistic trail. Using both univariate and multivariate brain imaging analyses, we find that a broad spectrum of brain activation discriminates between the mental simulation of plogging versus running. Critically, we show that self‐reported ratings of daily life running engagement and the quality of mental simulation (how well participants were able to imagine themselves running) modulate the brain reactivity to plogging versus running. Finally, we undertook functional connectivity analyses centered on the insular cortex, which is a key region in the dynamic interplay between neurocognitive processes. This analysis revealed increased positive and negative patterns of insular‐centered functional connectivity in the plogging condition (as compared to the running condition), thereby confirming the key role of the insular cortex in action simulation involving complex sets of mental mechanisms. Taken together, the present findings provide new insights into the brain networks involved in the enactive mental simulation of physical exercise.
Uncovering the hidden effects of repetitive subconcussive head impact exposure: A mega‐analytic approach characterizing seasonal brain microstructural changes in contact and collision sports athletes
Authors: Kwiatkowski Anna , Weidler Carmen , Habel Ute , Coverdale Nicole S. , Hirad Adnan A. , Manning Kathryn Y. , Rauscher Alexander , Bazarian Jeffrey J. , Cook Douglas J. , Li David K. B. , Mahon Bradford Z. , Menon Ravi S. , Taunton Jack , Reetz Kathrin , Romanzetti Sandro , Huppertz Charlotte 
Published: August 2024

AbstractRepetitive subconcussive head impacts (RSHI) are believed to induce sub‐clinical brain injuries, potentially resulting in cumulative, long‐term brain alterations. This study explores patterns of longitudinal brain white matter changes across sports with RSHI‐exposure. A systematic literature search identified 22 datasets with longitudinal diffusion magnetic resonance imaging data. Four datasets were centrally pooled to perform uniform quality control and data preprocessing. A total of 131 non‐concussed active athletes (American football, rugby, ice hockey; mean age: 20.06 ± 2.06 years) with baseline and post‐season data were included. Nonparametric permutation inference (one‐sample t tests, one‐sided) was applied to analyze the difference maps of multiple diffusion parameters. The analyses revealed widespread lateralized patterns of sports‐season‐related increases and decreases in mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) across spatially distinct white matter regions. Increases were shown across one MD‐cluster (3195 voxels; mean change: 2.34%), one AD‐cluster (5740 voxels; mean change: 1.75%), and three RD‐clusters (817 total voxels; mean change: 3.11 to 4.70%). Decreases were shown across two MD‐clusters (1637 total voxels; mean change: −1.43 to −1.48%), two RD‐clusters (1240 total voxels; mean change: −1.92 to −1.93%), and one AD‐cluster (724 voxels; mean change: −1.28%). The resulting pattern implies the presence of strain‐induced injuries in central and brainstem regions, with comparatively milder physical exercise‐induced effects across frontal and superior regions of the left hemisphere, which need further investigation. This article highlights key considerations that need to be addressed in future work to enhance our understanding of the nature of observed white matter changes, improve the comparability of findings across studies, and promote data pooling initiatives to allow more detailed investigations (e.g., exploring sex‐ and sport‐specific effects).
Precision fMRI and cluster‐failure in the individual brain
Authors: Ceja Igor Fabian Tellez , Gladytz Thomas , Starke Ludger , Tabelow Karsten , Niendorf Thoralf , Reimann Henning Matthias 
Published: August 2024

AbstractAdvances in neuroimaging acquisition protocols and denoising techniques, along with increasing magnetic field strengths, have dramatically improved the temporal signal‐to‐noise ratio (tSNR) in functional magnetic resonance imaging (fMRI). This permits spatial resolution with submillimeter voxel sizes and ultrahigh temporal resolution and opens a route toward performing precision fMRI in the brains of individuals. Yet ultrahigh spatial and temporal resolution comes at a cost: it reduces tSNR and, therefore, the sensitivity to the blood oxygen level‐dependent (BOLD) effect and other functional contrasts across the brain. Here we investigate the potential of various smoothing filters to improve BOLD sensitivity while preserving the spatial accuracy of activated clusters in single‐subject analysis. We introduce adaptive‐weight smoothing with optimized metrics (AWSOM), which addresses this challenge extremely well. AWSOM employs a local inference approach that is as sensitive as cluster‐corrected inference of data smoothed with large Gaussian kernels, but it preserves spatial details across multiple tSNR levels. This is essential for examining whole‐brain fMRI data because tSNR varies across the entire brain, depending on the distance of a brain region from the receiver coil, the type of setup, acquisition protocol, preprocessing, and resolution. We found that cluster correction in single subjects results in inflated family‐wise error and false positive rates. AWSOM effectively suppresses false positives while remaining sensitive even to small clusters of activated voxels. Furthermore, it preserves signal integrity, that is, the relative activation strength of significant voxels, making it a valuable asset for a wide range of fMRI applications. Here we demonstrate these features and make AWSOM freely available to the research community for download.
Measuring and reducing the carbon footprint of fMRI preprocessing in fMRIPrep
Authors: Souter Nicholas E. , Bhagwat Nikhil , Racey Chris , Wilkinson Reese , Duncan Niall W. , Samuel Gabrielle , Lannelongue Loïc , Selvan Raghavendra , Rae Charlotte L. 
Published: August 2024

AbstractComputationally expensive data processing in neuroimaging research places demands on energy consumption—and the resulting carbon emissions contribute to the climate crisis. We measured the carbon footprint of the functional magnetic resonance imaging (fMRI) preprocessing tool fMRIPrep, testing the effect of varying parameters on estimated carbon emissions and preprocessing performance. Performance was quantified using (a) statistical individual‐level task activation in regions of interest and (b) mean smoothness of preprocessed data. Eight variants of fMRIPrep were run with 257 participants who had completed an fMRI stop signal task (the same data also used in the original validation of fMRIPrep). Some variants led to substantial reductions in carbon emissions without sacrificing data quality: for instance, disabling FreeSurfer surface reconstruction reduced carbon emissions by 48%. We provide six recommendations for minimising emissions without compromising performance. By varying parameters and computational resources, neuroimagers can substantially reduce the carbon footprint of their preprocessing. This is one aspect of our research carbon footprint over which neuroimagers have control and agency to act upon.
Amoreuxia wrightii A. Gray (Cochlospermaceae) neu für Cuba
Authors: Günther Karl‐Friedrich 
Published: August 2024

ZusammenfassungIm Juni 1982 wurde in La Chivera bei Imías (Prov. Guantánamo) nach stärkeren Regenfällen ein Vertreter der Gattung Amoreuxia Moç. et Sessé ex DC. (Fam. Cochlospermaceae) gefunden. Dies ist der erste Fund einer Amoreuxia in Cuba und auf den Antillen überhaupt. Wenn man die Unsicherheiten auβer acht läβt, die z. Zt. bei der morphologischen Umgrenzung der wenigen Arten der Gattung herrschen, ist dieser Neufund zu A. urightii A. Gray zu zählen. Er fügt sich gut in das Areal dieser Art ein.A. wrightii wächst in Cuba auf relativ tiefgründigen Böden über Kalkstein auf der untersten Küstenterrasse in sekundär gelichtetem Trockengebüsch und an Wegrändern.
Chromosome structure rearrangements and genome relationship in Maydeae
Authors: Sharma A. K. , Sarma J. S. P. 
Published: August 2024

SummaryThis review attempts to lay stress on topics of current importance in addition to providing a comprehensive idea of pure and evolutionary aspects of cytogenetics of Maydeae.The classical concepts have been confirmed by experimentation in areas such as cytogenetics of heterochromatin. New insight has been obtained through analysis of genetic fine structure, regardingwxand other loci. Several gross duplications have been well analyzed within the genome of maize. Banding studies have provided an understanding of the structure of chromosomes at mitotic as well as meiotic stages. Mapping of loci for the specific genetic phenomena, utilizing B‐chromosome, is in progress using appropriate B‐A translocation complements. Monosomic studies have been much facilitated with the discovery of r‐xl deficiency. Ultrastructural patterns have revealed the mode of initiation and progress of synapsis. Studies involving hemizygosity have given a new dimension to cytogenetic mapping. Advanced analytical techniques have been employed to study the activity of several enzyme loci. Controlling element which itself should form a review by itself has not been dealt with in the present review.Recent discovery of diploperennial teosinte and intergenomic mapping studies within the American Maydeae, coupled with earlier studies on crossability relationships and pairing in hybrids, are contrary to the tripartite hypothesis Maize as a possible mutant derivative of teosinte is strongly advocated, A new theory — Cataclysmic sexual transmutation theory — has been advanced to explain the origin of maize ear from teosinte tassel.
Changes in peer belonging, school climate, and the emotional health of immigrant, refugee, and non‐immigrant early adolescents
Authors: Thomson Kimberly , Magee Carly , Gagné Petteni Monique , Oberle Eva , Georgiades Katholiki , Schonert‐Reichl Kimberly , Janus Magdalena , Guhn Martin , Gadermann Anne 
Published: August 2024

AbstractIntroductionEarly adolescents who are new to Canada experience dual challenges of navigating developmental changes and multiple cultures. This study examined how changes in early adolescents’ emotional health from ages 9 to 12 differed by immigration background, and to what extent peer belonging and supportive school climate protected or promoted their emotional health.MethodsThis study drew upon linked self‐report and administrative data. Across 10 school districts in British Columbia, Canada, N = 4479 non‐immigrant, immigrant, and refugee adolescents reported on their peer belonging, school climate, and emotional health (life satisfaction, optimism, self‐esteem, sadness, worries) in Grades 4 and 7, using the Middle Years Development Instrument. Immigration background including immigration class (economic, family, refugee) and generation status (first, second) were obtained from linked Immigration, Refugees, and Citizenship Canada data. Multi‐level modeling assessed the effect of time (grade level), immigration group, and changes in peer belonging and school climate on changes in self‐reported emotional health. Analyses were adjusted for gender, English first language, and low family income.ResultsImmigrant and refugee adolescents reported worse emotional health in Grade 4 compared to non‐immigrants. Non‐immigrant and immigrant adolescents reported declines in emotional health from Grades 4 to 7. In contrast, first‐generation refugee adolescents reported significant improvements in life satisfaction, and first‐ and second‐generation refugees reported improvements in worries over this period. Perceived improvements in peer belonging and school climate were associated with positive changes in emotional health for all adolescents.ConclusionsChanges in adolescents’ emotional health from Grades 4 to 7 differed between immigrants, refugees, and non‐immigrants. Immigrants and refugees who enter adolescence with lower emotional health than their non‐immigrant peers may particularly benefit from culturally responsive school and community‐based interventions.
Body composition parameters in initial CT imaging of mechanically ventilated trauma patients: Single‐centre observational study
Authors: Meyer Hans‐Jonas , Dermendzhiev Tihomir , Hetz Michael , Osterhoff Georg , Kleber Christian , Denecke Timm , Henkelmann Jeanette , Werdehausen Robert , Hempel Gunther , Struck Manuel F. 
Published: August 2024

AbstractBackgroundBody composition parameters provide relevant prognostic significance in critical care cohorts and cancer populations. Published results regarding polytrauma patients are inconclusive to date. The goal of this study was to analyse the role of body composition parameters in severely injured trauma patients.MethodsAll consecutive patients requiring emergency tracheal intubation and mechanical ventilation before initial computed tomography (CT) at a level‐1 trauma centre over a 12‐year period (2008–2019) were reanalysed. The analysis included CT‐derived body composition parameters based upon whole‐body trauma CT as prognostic variables for 30‐day mortality, intensive care unit length of stay (ICU LOS) and mechanical ventilation duration.ResultsFour hundred seventy‐two patients (75% male) with a median age of 49 years, median injury severity score of 26 and 30‐day mortality rate of 22% (104 patients) met the inclusion criteria and were analysed. Regarding body composition parameters, 231 patients (49%) had visceral obesity, 75 patients had sarcopenia (16%) and 35 patients had sarcopenic obesity (7.4%). After adjustment for statistically significant univariable predictors age, body mass index, sarcopenic obesity, visceral obesity, American Society of Anesthesiologists classification ≥3, injury severity score and Glasgow Coma Scale ≤ 8 points, the Cox proportional hazard model identified sarcopenia as significant prognostic factor of 30‐day mortality (hazard ratio 2.84; 95% confidence interval 1.38–5.85; P = 0.004), which was confirmed in Kaplan–Meier survival analysis (log‐rank P = 0.006). In a subanalysis of 363 survivors, linear multivariable regression analysis revealed no significant associations of body composition parameters with ICU LOS and duration of mechanical ventilation.ConclusionsIn a multivariable analysis of mechanically ventilated trauma patients, CT‐defined sarcopenia was significantly associated with 30‐day mortality whereas no associations of body composition parameters with ICU LOS and duration of mechanical ventilation were observed.
Exploring the utility of ultrasound to assess disuse atrophy in different muscles of the lower leg
Authors: Hardy Edward J. , Bass Joseph J. , Inns Thomas B. , Piasecki Mathew , Piasecki Jessica , Sale Craig , Morris Robert H. , Lund Jonathan N. , Smith Ken , Wilkinson Daniel J. , Atherton Philip J. , Phillips Bethan E. 
Published: August 2024

AbstractBackgroundSkeletal muscle is a highly plastic tissue crucial for many functions associated with whole‐body health across the life course. Magnetic resonance imaging (MRI) is the current gold standard for measuring skeletal muscle size. However, MRI is expensive, and access to facilities is often limited. B‐mode ultrasonography (U/S) has been proposed as a potential alternative to MRI for the assessment of muscle size. However, to date, no work has explored the utility of U/S to assess disuse muscle atrophy (DMA) across muscles with different atrophy susceptibility profiles, an omission which may limit the clinical application of previous work.MethodsTo address this significant knowledge gap, 10 young men (22 ± years, 24.1 ± 2.3 kg/m2) underwent 15‐day unilateral leg immobilization using a knee‐brace and air boot. Cross‐sectional area (CSA) and muscle thickness (MT) of the tibialis anterior (TA) and medial gastrocnemius (MG) were assessed via U/S before and after immobilization, with CSA and muscle volume assessed via MRI.ResultsWith both muscles combined, there were good correlations between each U/S and MRI measure, both before (e.g., CSAMRI vs. MTU/S and CSAU/S: r = 0.88 and 0.94, respectively, both P < 0.0001) and after (e.g., VOLMRI vs. MTU/S and CSAU/S: r = 0.90 and 0.96, respectively, both P < 0.0001) immobilization. The relationship between the methods was notably stronger for MG than TA at each time‐point (e.g., CSAMRI vs. MTU/S: MG, r = 0.70, P = 0.0006; TA, r = 0.37, P = 0.10). There was no relationship between the degree of DMA determined by the two methods in either muscle (e.g., TA pre‐ vs. post‐immobilization, VOLMRI: 136 ± 6 vs. 133 ± 5, P = 0.08; CSAU/S: 6.05 ± 0.3 vs. 5.92 ± 0.4, P = 0.70; relationship between methods: r = 0.12, P = 0.75).ConclusionsBoth MTU/S and CSAU/S provide comparable static measures of lower leg muscle size compared with MRI, albeit with weaker agreement in TA compared to MG. Although both MTU/S and CSAU/S can discern differences in DMA susceptibility between muscles, neither can reliably assess degree of DMA. Based on the growing recognition of heterogeneous atrophy profiles between muscles, and the topical importance of less commonly studied muscles (i.e., TA for falls prevention in older adults), future research should aim to optimize accessible methods to determine muscle losses across the body.
Factors associated with handgrip strength across the life course: A systematic review
Authors: Ribeiro Leticia W. , Berndt Sara , Mielke Gregore I. , Doust Jenny , Mishra Gita D. 
Published: August 2024

AbstractBackgroundMuscle strength is essential for healthy ageing. Handgrip strength (HGS) has been recommended by expert bodies as the preferred measure of muscle strength, in addition to being considered a strong predictor of overall health. Cross‐sectional studies have shown several potential factors associated with HGS, but a systematic review of factors predicting HGS over time has not previously been conducted. The aim of this study is to systematically review the literature on the factors associated with adult HGS [at follow‐up(s) or its rate of change] across the life course.MethodsSearches were performed in MEDLINE via Ebsco, Embase and SPORTDiscus databases. Longitudinal studies assessing potential factors impacting adult HGS over time were included in the analyses. Based on previously established definitions of consistency of results, a semiquantitative analysis was conducted using the proportions of studies supporting correlations with HGS.ResultsA total of 117 articles were included in this review. Factors associated with HGS were grouped into 11 domains: demographic, socioeconomic, genetic, early life, body composition, health markers/biomarkers, health conditions, psychosocial, lifestyle, reproductive and environmental determinants. Overall, 103 factors were identified, of which 10 showed consistent associations with HGS over time (i.e., in at least four studies with ≥60% agreement in the direction of association). Factors associated with greater declines in HGS included increasing age, male sex, higher levels of inflammatory markers and the presence of cardiovascular diseases. Education level, medication use, and self‐rated health were not associated with the rate of change in HGS. Increased birth weight was associated with a stronger HGS over time, whereas depressive symptoms were linked to a weaker HGS, and smoking habits showed null associations.ConclusionsComparison between studies and estimation of effect sizes were limited due to the heterogeneity in methods. Although sex and age may be the main drivers of HGS decline, it is crucial to prioritize modifiable factors such as inflammation and cardiovascular diseases in health interventions to prevent greater losses. Interventions to improve birth weight and mental health are also likely to produce positive effects on muscle strength. Our results point to the complexity of processes involving muscle strength and suggest that the need to better understand the determinants of HGS remains.