bluuebunny/crossref_metadata_2025_split huggingface dataset:
Global gradients in species richness of marine plankton functional groups
Authors: Benedetti Fabio , Gruber Nicolas , Vogt Meike 
Published: July 2023

AbstractThe patterns of species diversity of plankton functional groups (PFGs) remain poorly understood although they matter for marine ecosystem functioning. Here, we use an ensemble of empirical species distribution models for 845 plankton species to estimate the mean annual global species richness of three phytoplankton and eleven zooplankton functional groups as a function of objectively selected environmental predictors. The species richness of all PFGs decreases from the low to the high latitudes, but the steepness and the shape of this decrease varies significantly across PFGs. Pteropods, small copepods (Oithonids and Poecilostomatoids) and Salps show the steepest latitudinal gradients, whereas Amphipods and the three phytoplankton groups show the weakest ones. While the position of such peaks and troughs in richness is modulated by the presence of upwelling systems, boundary currents and oxygen minimum zones, the gradients of temperature, irradiance, and nutrient concentration are the first-order control on the main latitudinal richness patterns. The species richness of all PFGs increases with net primary production but decreases with particles size and the efficiency of the biological carbon pump. Our study puts forward emergent Biodiversity-Ecosystem Functioning relationships and hypotheses about their underlying drivers for future field-based and modelling research.
Detecting ataxia using an automated analysis of motor coordination and balance of mice on the balance beam
Authors: Wahl Lucas , Kaiser Fabian M.P. , Bentvelzen Mieke , White Joshua , Schonewille Martijn , Badura Aleksandra 
Published: July 2023

AbstractBackgroundThe balance beam assay is a well-known paradigm to assess motor coordination in mouse models of neurodegenerative diseases. Classically, these experiments have been quantified using manual annotation, which is time-consuming and prone to inter-experimenter variability.MethodsWe present an open-source analysis pipeline that allows for the automated quantification of motor function. Using an established ataxia model, we validated the pipeline by comparing its output to three independent observers.ResultsPcp2-Ppp3r1mutant animals showed a significant increase in the number of missteps and increased time to traverse the beam.ConclusionWe show that our pipeline can reliably report crossing time, missteps, stops, and falls, thereby offering a high-throughput option with increased inter-experimenter reliability for the analysis of balance beam data.Significance statementThe analysis of mouse behaviour and motor coordination experiments often lacks automation and standardisation and is thus time-consuming and prone to inter-experimenter variability and poor reproducibility. The balance beam assay is a well-established motor coordination paradigm and currently lacks such an automated, standardised analysis platform. We have developed an open-source pipeline that allows for the automated analysis of crossing time, missteps, stops, and falls. Together with a standardised, easy to assemble balance beam setup, our pipeline offers a cost-effective, and high-throughput option to generate and analyse balance beam data with increased inter-experimenter and intra-experimenter reliability.
Neural envelope tracking predicts speech intelligibility and hearing aid benefit in children with hearing loss
Authors: Van Hirtum Tilde , Somers Ben , Dieudonné Benjamin , Verschueren Eline , Wouters Jan , Francart Tom 
Published: July 2023

AbstractEarly assessment of hearing aid benefit is crucial, as the extent to which hearing aids provide audible speech information predicts speech and language outcomes. A growing body of research has proposed neural envelope tracking as an objective measure of speech, particularly for individuals unable to provide reliable behavioral feedback. However, its potential for evaluating speech intelligibility and hearing aid benefit in hearing-impaired children remains unexplored. This study examined neural envelope tracking in hearing-impaired children through two separate experiments. EEG data was recorded while children listened to age-appropriate stories (experiment 1) or an animated movie (experiment 2) under aided and unaided conditions (using personal hearing aids) at multiple stimulus intensities. Results in the delta band demonstrated that neural tracking increased with increasing stimulus intensity, but only in the unaided condition. In the aided condition, neural tracking remained stable across a wide range of intensities, as long as speech intelligibility was maintained. This suggests that acoustic degradation of the speech signal does not necessarily impact neural tracking. Additionally, the use of personal hearing aids significantly enhanced neural envelope tracking, particularly in challenging speech conditions (which would be inaudible when unaided). Furthermore, neural envelope tracking strongly correlated with behaviorally measured speech intelligibility. Altogether, these findings indicate that neural envelope tracking could be a valuable tool for predicting speech intelligibility benefits derived from personal hearing aids in hearing-impaired children. Incorporating narrated stories or engaging movies expands the accessibility of these methods even in clinical settings, offering new avenues for using objective speech measures to guide pediatric audiology decision-making.
Combining high-density electromyography and ultrafast ultrasound to assess individual motor unit propertiesin vivo
Authors: Carbonaro M. , Rohlén R. , Seoni S. , Meiburger K. M. , Vieira T. , Grönlund C. , Botter A. 
Published: July 2023

AbstractThis study aims to compare two methods for the identification of anatomical and mechanical motor unit (MU) properties through the integration of high-density surface electromyography (HDsEMG) and ultrafast ultrasound (UUS). The two approaches rely on a combined analysis of the firing pattern of active MUs, identified from HDsEMG, and tissue velocity sequences of the muscle cross-section, obtained from UUS. The first method is the spike-triggered averaging (STA) of the tissue velocity sequence based on the occurrences of MU firings. The second is a method based on spatio-temporal independent component analysis (STICA) enhanced with the information of single MU firings. We compared the capability of these two approaches to identify the regions where single MU fibers are located within the muscle cross-section (MU displacement area)in vivo. HDsEMG signals and UUS images were detected simultaneously from biceps brachii in ten participants (6 males and 4 females) during low-level isometric elbow flexions. Experimental signals were processed by implementing both STA and STICA approaches. The medio-lateral distance between the estimated MU displacement areas and the centroid of the MU action potential distributions was used to compare the two methods. We found that STICA and STA are able to detect MU displacement areas. However, STICA provides more precise estimations to the detriment of higher computational complexity.
Dynein and dynactin move long-range but are delivered separately to the axon tip
Authors: Fellows Alexander D , Bruntraeger Michaela , Burgold Thomas , Bassett Andrew R , Carter Andrew P 
Published: July 2023

AbstractAxonal transport is essential for neuronal survival. This is driven by microtubule motors including dynein, which transports cargo from the axon tip back to the cell body. This function requires its cofactor dynactin and regulators LIS1 and NDEL1. Due to difficulties imaging dynein at a single-molecule level, it is unclear how this motor and its regulators coordinate transport along the length of the axon. Here we use neuron-inducible human stem-celllines (NGN2-OPTi-OX) to endogenously tag dynein components and visualise them at a near-single molecule regime. In the retrograde direction, we find that dynein and dynactin can move the entire length of the axon (>500μm) in one go. Furthermore, LIS1 and NDEL1 also undergo longdistance movement, despite being mainly implicated with initiation of dynein transport. Intriguingly, in the anterograde direction, dynein/LIS1 move faster than dynactin/NDEL1 consistent with transport on different cargos. Therefore, neurons ensure efficient transport by holding dynein/dynactin on cargos over long distances, but keeping them separate until required.
Maintenance of colour memoranda in activity-quiescent working memory states: Evidence from impulse perturbation
Authors: Kandemir Güven , Wilhelm Sophia A. , Axmacher Nikolai , Akyürek Elkan G. 
Published: July 2023

AbstractThe neural mechanisms underlying working memory maintenance pose a challenge for investigation, as sustained neural activity may not always be observable. To address this, the method of impulse perturbation has been employed to examine memorized information during activity-quiescent periods. However, this approach has mainly focused on spatially localized or referenced stimuli, leaving it unclear whether non-spatial memoranda share similar neural maintenance mechanisms. This study aimed to fill this gap by applying the impulse perturbation method to working memory for colours, which are inherently non-spatial stimuli. EEG data from 30 participants performing a delayed match-to-sample task were analysed, with one of the presented items being retro-cued as task-relevant. Our findings indicate that both cued and uncued colours could be decoded from impulse-evoked activity, in contrast to previous reports on working memory for orientation gratings. Additionally, we explored colour decoding from ongoing oscillations in the alpha band and discovered that cued items could be decoded, potentially influenced by attention, whereas uncued items could not. These results suggest subtle differences between the representation of colours and stimuli with spatial properties. However, they also demonstrate that both types of information can be accessed through visual impulse perturbation, regardless of their specific neural states.
A unified framework to identify demographic buffering in natural populations
Authors: Santos Gabriel Silva , Gascoigne Samuel J L , Dias André Tavares Corrêa , Kajin Maja , Salguero-Gómez Roberto 
Published: July 2023

AbstractThe Demographic Buffering Hypothesis (DBH) predicts that natural selection reduces the temporal fluctuations in demographic processes (such as survival, development, and reproduction), due to their negative impacts on population dynamics. However, a comprehensive approach that allows for the examination of demographic buffering patterns across multiple species is still lacking. Here, we propose a three-step framework aimed at identifying and quantifying demographic buffering. Firstly, we categorize species along a continuum of variance based on their stochastic elasticities. Secondly, we examine the linear selection gradients, followed by the examination of nonlinear selection gradients as the third step. With these three steps, our framework overcomes existing limitations of conventional approaches to identify and quantify demographic buffering, allows for multi-species comparisons, and offers an insight into the evolutionary forces that shape demographic buffering. We apply this framework to mammal species and discuss both the advantages and potential of our framework.
Exploring the Dose-Dependency of After-Effects: A Computational Model for Theta-Burst Transcranial Magnetic Stimulation
Authors: Ma Ke , Chung Sung Wook , Goetz Stephan M. 
Published: July 2023

AbstractTranscranial magnetic stimulation (TMS) is a non-invasive neurostimulation and neuromodulation technique that is widely applied in brain research and clinical applications. However, the optimal parameters of neuromodulating TMS protocols describing the specific rhythms, such as number of pulses, frequency, and stimulation strength, are widely unknown. Improving previous rather limited and ad-hoc models, we aimed to investigate the dose-dependency of theta-burst stimulation (TBS) protocols with a more elaborate but still parsimonious quantitative model representing the non-linearities of the mechanisms of synaptic plasticity and metaplasticity during repetitive magnetic stimulation. Our model, which considers the interaction between facilitatory and inhibitory processes, successfully reproduced results from TBS experiments and provide testable predictions for prolonged TBS protocols. Moreover, we suggested that the activation of kinases and phosphatases could be potential candidates for later TMS modelling research. Although this model still simplifies the complex dynamics of cellular and molecular processes, it offers a starting basis for future studies to incorporate more intricate mechanisms. By further refining our understanding of the underlying mechanisms and improving the accuracy of prediction models, we can advance the efficacy and clinical application of TBS protocols in various neurological and psychiatric conditions.
Microbiome Prevents Sudden Death Through Occult Cardiac Sub-micrometastasis in Mice
Authors: Aalam Syed Mohammed Musheer , Tang Xiaojia , Hari PS , Salem Salem M. , Al Jarrad Ahmad , Noseworthy Peter A. , Behfar Atta , Sadanandam Anguraj , Kalari Krishna , Kashyap Purna C. , Kannan Nagarajan 
Published: July 2023

AbstractSudden cardiac deaths (SCDs) pose a formidable clinical challenge, and their underlying risk mechanisms are poorly understood. Using a gnotobiotic, germ-free mouse model, we fortuitously discovered SCD incidences resulting from occult cardiac metastases. Female germ-free C57BL/6 mice (n=22) were raised in isolation and injected with mammary Py230 cells. Significantly higher SCD probabilities (36.3%) were observed in germ-free mice compared to gut-colonized groups (0%). Extensive examinations revealed no physical anomalies but demonstrated occult cardiac sub-micrometastasis in three out of four sudden death cases. Further analysis supported the role of occult cardiac sub-micrometastasis as the leading cause of SCDs. The remaining germ-free mice exhibited minimal primary tumors but high levels of cardiac metastases and morbidity. The gnotobiotic SCD model represents a crucial milestone in our understanding of the complex interplay between the gut microbiota and the development of occult oncological processes that ultimately culminate in SCDs and warrants further investigation into their mechanisms.
When the tap runs dry: The physiological effects of acute experimental dehydration inPeromyscus eremicus
Authors: Blumstein Danielle M. , MacManes Matthew D. 
Published: July 2023

AbstractDesert organisms have evolved physiological, biochemical, and genomic mechanisms to survive the extreme aridity of desert environments. Studying desert-adapted species provides a unique opportunity to investigate the survival strategies employed by organisms in some of the harshest habitats on Earth. Two of the primary challenges faced in desert environments are maintaining water balance and thermoregulation. We collected data in a simulated desert environment and a captive colony of cactus mice (Peromyscus eremicus) and used lab-based experiments with real time physiological measurements to characterize the response to water-deprivation. Mice without access to water had significantly lower energy expenditures and in turn, reduced water loss compared to mice with access to water after the first 24 hours of the experiment. Additionally, we observed significant weight loss likely related to dehydration-associated anorexia a response to limit fluid loss by reducing waste and the solute load as well as allowing water reabsorption from the kidneys and gastrointestinal tract. Finally, we observed body temperature correlated with sex, with males without access to water maintaining body temperature when compared to hydrated males while body temperature decreased for females without access to water compared to hydrated, suggesting daily torpor in females.
Purkinje cell dysfunction causes disrupted sleep in ataxic mice
Authors: Salazar Leon Luis E. , Brown Amanda M. , Kaku Heet , Sillitoe Roy V. 
Published: July 2023

AbstractPurkinje cell dysfunction causes movement disorders such as ataxia, however, recent evidence suggests that Purkinje cell dysfunction may also alter sleep regulation. Here, we used an ataxia mouse model generated by silencing Purkinje cell neurotransmission (L7Cre;Vgatfx/fx) to better understand how cerebellar dysfunction impacts sleep physiology. We focused our analysis on sleep architecture and electrocorticography (ECoG) patterns based on their relevance to extracting physiological measurements during sleep. We found that circadian activity is unaltered in the mutant mice, although their sleep parameters and ECoG patterns are modified. TheL7Cre;Vgatfx/fxmutant mice have decreased wakefulness and rapid eye movement (REM) sleep, while non-rapid eye movement (NREM) sleep is increased. The mutant mice have an extended latency to REM sleep, which is also observed in human ataxia patients. Spectral analysis of ECoG signals revealed alterations in the power distribution across different frequency bands defining sleep. Therefore, Purkinje cell dysfunction may influence wakefulness and equilibrium of distinct sleep stages in ataxia. Our findings posit a connection between cerebellar dysfunction and disrupted sleep and underscore the importance of examining cerebellar circuit function in sleep disorders.Summary StatementUtilizing a precise genetic mouse model of ataxia, we provide insights into the cerebellum’s role in sleep regulation, highlighting its potential as a therapeutic target for motor disorders-related sleep disruptions.
Human behavior and comfort during load carrying to autonomous mobile robot
Authors: Tamura Hideki , Konno Taiki , Nakauchi Shigeki , Minami Tetsuto 
Published: July 2023

AbstractInteractions between humans and autonomous mobile robots (AMRs) are expected to grow in smart cities to improve logistics operations, such as depositing packages on AMRs for pickup on the street. However, the way that humans walk and pass objects to an AMR when approaching each other remains largely unknown. We conducted two psychophysical experiments to clarify the behavior and comfort of humans when carrying a package and placing it on an AMR for load carrying. Participants were asked to approach a programmed AMR and pass the package in two experiments: 1) changing the stop distance and AMR speed and 2) changing the stop distance and package weight. Motion trackers quantified the participants’ walking speed and frequency of hesitation to walk. In addition, the subjective heaviness and comfort were recorded through a questionnaire during each trial. The results indicated that the participants’ speed decreased and hesitation probability increased when the stop distance of the AMR decreased. Nevertheless, the participants felt more comfortable with the close approach, whereas the package weight did not affect their behavior. By contrast, they felt uncomfortable when AMR remained still. These findings suggest that humans regard the AMR approach as load-carrying assistance and not as invading their personal space. To achieve a comfortable interaction in load carrying from humans to AMRs, we suggest that the AMR can closely approach a person without eliciting personal space invasion.
SrcapHaploinsufficiency Induced Autistic-Like Behaviors in Mice through Disruption ofSatb2Expression
Authors: Ding Chaodong , Shi Yuhan , Shan Shifang , Yuan Yiting , Zhang Yuefang , Qiu Zilong 
Published: July 2023

AbstractAutism spectrum disorder (ASD) is a complex neurodevelopmental disorder with significant genetic predispositions. Among these, loss-of-function mutations of the chromatin remodeling geneSRCAPhave been identified in individuals with ASD, but their pathogenic mechanisms have yet to be fully elucidated. In this study, we established a germline mutant mouse model harboring a heterozygous frameshift mutation in theSrcapgene (Srcap+/-). TheSrcap+/-mice exhibited notable impairments in social novelty, repetitive and stereotyped behaviors, anxiety, and learning and memory deficits. We observed a decreased number of parvalbumin (PV)-expressing neurons in their retrosplenial cortex (RSC) and dentate gyrus (DG). Furthermore, abnormalities in dendritic structure, synaptic density, and synaptic transmission were noted in the DG ofSrcap+/-mice. RNA sequencing revealed that the expression of 27 genes, implicated in ASD, was dysregulated in theSrcaphaploinsufficiency mice. Among these genes, we found thatSrcaphaploinsufficiency resulted in decreasedSatb2expression due to diminished H2A.z-binding within the promoter region ofSatb2. Remarkably, intervention through retro-orbital injection of AAV vectors expressingSatb2in newbornSrcap+/-mice reversed autistic-like behaviors and developmental defects in the RSC and DG regions. Similarly, in adolescentSrcap+/-mice, stereotactic injection of AAV expressingSatb2into the RSC ameliorated deficits in social novelty. Collectively, these findings highlight the crucial role of theSrcapin neurodevelopment by regulatingSatb2expression, particularly impacting the development of RSC and DG regions.