Hasil untuk "Neurophysiology and neuropsychology"

Annika Delucchi, Vincenzo Di Paola, Andreas Müller et al.

Although strain-based models have been widely adopted in robotics, no comparison beyond the uniform bending test is commonly recognized to assess their performance. In addition, the increasing effort in prototyping continuum robots highlights the need to assess the applicability of these models and the necessity of comprehensive performance evaluation. To address this gap, this work investigates the shape reconstruction abilities of a third-order strain interpolation method, examining its ability to capture both individual and combined deformation effects. These results are compared and discussed against the Geometric-Variable Strain approach. Subsequently, simulation results are experimentally verified by reshaping a slender rod while recording the resulting configurations using cameras. The rod configuration is imposed using a manipulator displacing one of its tips and extracted through reflective markers, without the aid of any other external sensor -- i.e. strain gauges or wrench sensors placed along the rod. The experiments demonstrate good agreement between the model predictions and observed shapes, with average error of 0.58% of the rod length and average computational time of 0.32s per configuration, outperforming existing models.

Galit Karpov, Sara A. Heyn, Justin D. Russell et al.

Background: Adolescence is a period that coincides with a peak in both the onset of psychopathology and a sensitive period for neural development. One transdiagnostic characteristic of psychopathology is impaired emotion regulation (ER), a process with both implicit (automatic) and explicit (voluntary) underpinnings. The current study aims to better understand the normative neurodevelopment of these two components of ER in adolescents. Methods: 139 youth (aged 10–20 years) completed ER assessment during fMRI at baseline and one-year follow-up. Implicit and explicit ER were examined using an emotional N-Back and a cognitive reappraisal task, respectively. Linear-mixed effects modeling was used to identify regions of the frontal cortex (Schaefer atlas) and the amygdala and hippocampus (Tian atlas) whose activity was predicted by ER- and age-related variables, covaried for sex, childhood adversity, and psychopathology symptoms. Results: Regions that displayed change across age were localized to the salience/ventral attention network in the right hemisphere. For implicit ER, mid-insula activity showed changes during early adolescence (∼10 years old), such that activity to negative stimuli increased during this time before plateauing. For explicit ER, the posterior insula, Rolandic Operculum, and paracentral lobule showed linear decreases in activity across the entire age range, where the decrease occurred at a faster rate in response to neutral relative to negative stimuli. Conclusions: Functional changes in frontal circuits related to emotional attention may encode the development of ER during neurodevelopment. Maturation of these circuits seem to reach completion by mid-adolescence for implicit ER, but explicit ER continues developing across adolescence.

Juan Felipe Huan Lew-Yee, Ion Mitxelena, Jorge M. del Campo et al.

In this work, we present the second version of the Donostia Natural Orbital Functional Software, an open-source program for natural orbital functional calculations. The new release incorporates improved optimization algorithms, capabilities for excited-state computations, support for ab initio molecular dynamics, and integration with the libcint library. DoNOF 2.0 also extends its property toolbox by enabling the evaluation of nonlinear optical responses, including static polarizabilities and higher-order hyperpolarizabilities via a finite-field Romberg-Richardson scheme. Program Summary [Title: DoNOF; Developer's repository link: http://github.com/DoNOF/; Program's Manual link: https://donof.readthedocs.io/; Licensing provisions: GPLv3; Programming language: Fortran; additional implementations available in Python (PyNOF) and Julia (DoNOF.jl); Multinode capability: Support for distributed execution through a hybrid OpenMPI and OpenMP implementation]

A.E. Ndou, L. Makhado, O.P. Netshisaulu

Epilepsy is a neurological disorder affecting individuals of all ages, often surrounded by stigma and misconceptions. Despite its prevalence, awareness about epilepsy is limited, particularly among university students. This study investigates the knowledge, attitudes, and perceptions of students at the University of Venda regarding epilepsy to identify gaps and improve educational strategies. A cross-sectional survey was conducted with students from various faculties at the University of Venda. Participants completed a structured questionnaire that collected demographic information and assessed their knowledge about epilepsy, attitudes towards individuals with the condition, and perceptions of public awareness. The survey included questions about awareness of epilepsy, understanding its causes and management, and views on the rights of people living with epilepsy. A total of 326 students participated in the survey. The survey showed that approximately 92.9% of students had heard of epilepsy, but many misconceptions remained. A significant number believed that epilepsy is untreatable and that those with the condition should not drive or participate in certain activities. Only 18.7% knew the correct management practices for seizures. Furthermore, 67% of students felt that insufficient attention was given to epilepsy, yet the study increased interest in learning more, as over 92.9% expressed a desire for additional information. The findings highlight the need for better education about epilepsy among university students to dispel myths and promote informed attitudes. Educational initiatives focused on seizure management and inclusivity could create a more supportive environment for individuals with epilepsy at the University of Venda and beyond.

Anne-Wil Kramer, Lydia Krabbendam, Jessica V. Schaaf et al.

Adolescence is characterized by significant shifts in effort allocation. A well-known neuro-economic framework suggests that rewards help overcome potential effort costs. However, few studies have examined the neurobiological mechanisms by which rewards and associated effort costs drive adolescent learning. This study utilized functional magnetic resonance imaging in a sample of adolescents (N = 146, 13–25 years) and employed a reinforcement-learning paradigm that manipulated effort and reward levels, by varying task demands and varying potential rewards. The analysis of trial-by-trial learning signals (reward prediction errors) and behavioral learning performance demonstrated that greater reward levels enhanced adolescent learning, especially when faced with greater effort demands. Moreover, this effect was more pronounced in those experiencing greater effort demands: younger adolescents and adolescents who place less value on effort for demanding tasks. Neuroimaging results revealed that the dorsal anterior cingulate cortex (dACC) was a key region in signaling the interaction between reward and effort demands. That is, greater reward strengthened prediction error coding in the dACC, particularly under conditions of greater task demands, with these effects being more pronounced in younger adolescents and adolescents who place less value on effort for demanding tasks. These findings support a role for dACC in the engagement of cognitive control, especially in situations where more cognitive control would be beneficial despite its associated effort costs, such as in high-demanding learning situations. This comprehensive approach aims to inform strategies for supporting effort allocation in learning during this crucial developmental period.

Li-Fang Zhu, Fritz Koermann, Qing Chen et al.

Melting properties are critical for designing novel materials, especially for discovering high-performance, high-melting refractory materials. Experimental measurements of these properties are extremely challenging due to their high melting temperatures. Complementary theoretical predictions are, therefore, indispensable. The conventional free energy approach using density functional theory (DFT) has been a gold standard for such purposes because of its high accuracy. However,it generally involves expensive thermodynamic integration using ab initio molecular dynamic simulations. The high computational cost makes high-throughput calculations infeasible. Here, we propose a highly efficient DFT-based method aided by a specially designed machine learning potential. As the machine learning potential can closely reproduce the ab initio phase space, even for multi-component alloys, the costly thermodynamic integration can be fully substituted with more efficient free energy perturbation calculations. The method achieves overall savings of computational resources by 80% compared to current alternatives. We apply the method to the high-entropy alloy TaVCrW and calculate its melting properties, including melting temperature, entropy and enthalpy of fusion, and volume change at the melting point. Additionally, the heat capacities of solid and liquid TaVCrW are calculated. The results agree reasonably with the calphad extrapolated values.

Ben Simner, Alasdair Armstrong, Thomas Bauereiss et al.

To manage exceptions, software relies on a key architectural guarantee, precision: that exceptions appear to execute between instructions. However, this definition, dating back over 60 years, fundamentally assumes a sequential programmers model. Modern architectures such as Arm-A with programmer-observable relaxed behaviour make such a naive definition inadequate, and it is unclear exactly what guarantees programmers have on exception entry and exit. In this paper, we clarify the concepts needed to discuss exceptions in the relaxed-memory setting -- a key aspect of precisely specifying the architectural interface between hardware and software. We explore the basic relaxed behaviour across exception boundaries, and the semantics of external aborts, using Arm-A as a representative modern architecture. We identify an important problem, present yet unexplored for decades: pinning down what it means for exceptions to be precise in a relaxed setting. We describe key phenomena that any definition should account for. We develop an axiomatic model for Arm-A precise exceptions, tooling for axiomatic model execution, and a library of tests. Finally we explore the relaxed semantics of software-generated interrupts, as used in sophisticated programming patterns, and sketch how they too could be modelled.

ZiDong Wang, Zeyu Lu, Di Huang et al.

\textit{Nature is infinitely resolution-free}. In the context of this reality, existing diffusion models, such as Diffusion Transformers, often face challenges when processing image resolutions outside of their trained domain. To address this limitation, we conceptualize images as sequences of tokens with dynamic sizes, rather than traditional methods that perceive images as fixed-resolution grids. This perspective enables a flexible training strategy that seamlessly accommodates various aspect ratios during both training and inference, thus promoting resolution generalization and eliminating biases introduced by image cropping. On this basis, we present the \textbf{Flexible Vision Transformer} (FiT), a transformer architecture specifically designed for generating images with \textit{unrestricted resolutions and aspect ratios}. We further upgrade the FiT to FiTv2 with several innovative designs, includingthe Query-Key vector normalization, the AdaLN-LoRA module, a rectified flow scheduler, and a Logit-Normal sampler. Enhanced by a meticulously adjusted network structure, FiTv2 exhibits $2\times$ convergence speed of FiT. When incorporating advanced training-free extrapolation techniques, FiTv2 demonstrates remarkable adaptability in both resolution extrapolation and diverse resolution generation. Additionally, our exploration of the scalability of the FiTv2 model reveals that larger models exhibit better computational efficiency. Furthermore, we introduce an efficient post-training strategy to adapt a pre-trained model for the high-resolution generation. Comprehensive experiments demonstrate the exceptional performance of FiTv2 across a broad range of resolutions. We have released all the codes and models at \url{https://github.com/whlzy/FiT} to promote the exploration of diffusion transformer models for arbitrary-resolution image generation.

Liu F, Cao T, Liu Y et al.

Fei Liu,1,&ast; Tianqing Cao,1,&ast; Yacong Liu,1 Dian Huang,2 Jingxin Zhang3 1Department of Cardiology, Northern Jiangsu People’s Hospital Affiliated to Yangzhou University, Yangzhou, Jiangsu, 225001, People’s Republic of China; 2Department of Radiology, Affiliated hospital of Jiangsu University, Zhenjiang, Jiangsu, 212001, People’s Republic of China; 3Department of General Surgery, People’s Hospital Affiliated to Jiangsu University, Zhenjiang, Jiangsu, 212002, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Jingxin Zhang, Email zfynjykd@163.comObjective: The main purpose of this study is to evaluate the changes in sleep quality among patients with cirrhotic cardiomyopathy (CCM).Methods: The study included liver cirrhosis patients aged 18– 75 from Northern Jiangsu People’s Hospital Affiliated to Yangzhou University and collected their clinical examination results to assess the clinical characteristics and related risk factors of patients with CCM.Results: The study found that the onset of CCM was not related to the etiology of inducing cirrhosis. Pittsburgh Sleep Quality Index (PSQI) score (odds ratio (OR) = 13.476, 95% confidence interval (CI) = 1.514– 119.923, P = 0.020), absolute GLS (OR = 0.328, 95% CI = 0.210– 0.510, P < 0.001), and N-terminal pro-B-type natriuretic peptide (NT-proBNP) (OR = 1.050, 95% CI = 1.025– 1.076, P < 0.001) were identified as independent risk factors for inducing CCM.Conclusion: In patients with CCM, a decrease in sleep quality often occurs. When cirrhotic patients also have poor sleep quality, along with a decrease in absolute Global Left Ventricular Strain (GLS) levels and an increase in NT-proBNP levels, these factors may pose a higher risk for CCM development. However, further validation of these research findings is required in larger sample sizes.Keywords: cardiomyopathy, liver cirrhosis, sleep quality, cirrhotic cardiomyopathy

Cedric Foucault, Florent Meyniel

Savannah Brannan, Lauren Garbe, Ben D. Richardson

Adverse childhood experiences have been associated with many neurodevelopmental and affective disorders including attention deficit hyperactivity disorder and generalized anxiety disorder, with more exposures increasing negative risk. Sex and genetic background are biological variables involved in adverse psychiatric outcomes due to early life trauma. Females in general have an increased prevalence of stress-related psychopathologies beginning after adolescence, indicative of adolescence being a female-specific sensitive period. To understand the underlying neuronal mechanisms potentially responsible for this relationship between genetic background, sex, stress/trauma, and cognitive/affective behaviors, we assessed behavioral and neuronal changes in a novel animal model of early life stress exposure. Male and female BALB/cJ mice that express elevated basal anxiety-like behaviors and differences in monoamine signaling-associated genes, were exposed to an early life variable stress protocol that combined deprivation in early life with unpredictability in adolescence. Stress exposure produced hyperlocomotion and attention deficits (5-choice serial reaction time task) in male and female mice along with female-specific increased anxiety-like behavior. These behavioral changes were paralleled by reduced excitability of locus coeruleus (LC) neurons, due to resting membrane potential hyperpolarization in males and a female-specific increase in action potential delay time. These data describe a novel interaction between sex, genetic background, and early life stress that results in behavioral changes in clinically relevant domains and potential underlying mechanistic lasting changes in physiological properties of neurons in the LC.

R. R. Ullah, P. Klavins, X. D. Zhu et al.

Two ferromagnetic phases, FM1 and FM2, were first proposed to exist in LaCrGe$_3$ based on a broad maximum in the temperature derivative of resistivity resembling that of the superconducting ferromagnet UGe$_2$ where FM1 and FM2 are well-established. While evidence for two FM phases can be found in certain additional probes, corresponding anomalies in magnetization have not been recognized until now. Our spatially-resolved images of the magnetic domains show a substantial change in the domain structure between the higher temperature FM1 phase and the lower temperature FM2 phase. Furthermore, our measurements of the coercive field and virgin magnetization curves reveal an unconventional magnetic domain pinning region in the FM1 phase, followed by a depinning region at lower temperatures where the system is reported to crossover into the FM2 phase. We incorporate this discovery into a simple domain magnetization model that demystifies the magnetization curve seen in all previous studies. Finally, we find that the unusual domain behavior can be explained by a change in the ferromagnetic exchange interaction and magnetic moment, both of which are consistent with the existence of two FM phases. This revelation may help explain a range of anomalous behaviors observed in LaCrGe$_3$ and rekindles the discussion about the prevalence of multiple FM phases in fragile FM systems.

Krzysztof Sobucki, Wojciech Śmigaj, Piotr Graczyk et al.

We numerically demonstrate the excitation of leaky spin waves (SWs) guided along a ferromagnetic stripe by an obliquely incident SW beam on the thin film edge placed below the stripe. During propagation, leaky waves emit energy back to the layer in the form of plane waves and several laterally shifted parallel SW beams. This resonance excitation, combined with interference effects of the reflected and re-emitted waves, results in the magnonic Woods anomaly and significant increase of the Goos-Hanchen shift magnitude. Hence, we provide a unique platform to control SW reflection and to transfer SWs from a 2D platform into the 1D guiding mode that can be used to form a transdimensional magnonic router.

Sihong Chen, Taisong Pan, Zhengcheng Mou et al.

The sensitivity to deformation plays a key role in determining the applicability of stretchable metamaterials (MMs) to be used for conformal integration or mechanical reconfiguration. Typically, different unit designs are required to achieve the desired sensitivity, but this article proposes a block definition design for stretchable MMs that enables regulation of the MMs' response to deformation by defining various block arrangements with the same precursor structure. The article demonstrates a stretchable MM that employs the block definition design to show the mechanical reconfigurability of resonant frequency. Different block definitions result in modulation ranges of resonant frequency ranging from 39\% to 85\% when applying a 20\% tensile strain. Additionally, the proposed design is also used to realize another MM with contradictory sensitivity to the deformation and electromagnetically induced transparency (EIT) MMs with configurable transmission bandwidth to the deformation, indicating its potential for broader applications.

Zhaowei Chang, Jianhua Zhang, Pan Tang et al.

Terahertz (THz) communication is envisioned as one of the possible technologies for the sixth-generation (6G) communication system due to its rich spectrum. To evaluate the performance of THz communication, it is essential to propose THz channel models within the common framework of the geometry-based stochastic model (GBSM) in the 3rd Generation Partnership Project (3GPP). This paper focuses on THz channel modeling and simulation by a 3GPP-like GBSM, based on channel measurements. We first present channel measurements at 100 GHz in an indoor office scenario and 132 GHz in an urban microcellular scenario. Subsequently, channel characteristics such as path loss, delay spread, angle spread, K-factor, cluster characteristic, cross-correlations, and correlation distances are obtained and analyzed based on channel measurement. Additionally, the channel characteristics are modeled by the statistical distribution of 3GPP channel models, which can be used to reconstruct the channel impulse response (CIR). Furthermore, these obtained distributions are studied referring to the default models in the 3GPP, revealing the channel sparsity in the THz channel. For instance, in the case of line-of-sight links in the indoor office, the mean of the measured cluster number is 4 while the default value is 15. Finally, we propose the THz channel model and its simulation framework to reconstruct CIRs based on the obtained models, which aim at characterizing the sparser THz channels. The obvious channel sparsity is characterized in both scenarios, as the Gini factors obtained by the proposed model only have the maximum deviation of 0.04 for those of the measurement. Overall, these findings are helpful in understanding and modeling the THz channel, facilitating the application of THz communication techniques for 6G.

Abdulrahman Alabduljabbar, Runyu Ma, Ahmed Abusnaina et al.

Free content websites that provide free books, music, games, movies, etc., have existed on the Internet for many years. While it is a common belief that such websites might be different from premium websites providing the same content types, an analysis that supports this belief is lacking in the literature. In particular, it is unclear if those websites are as safe as their premium counterparts. In this paper, we set out to investigate, by analysis and quantification, the similarities and differences between free content and premium websites, including their risk profiles. To conduct this analysis, we assembled a list of 834 free content websites offering books, games, movies, music, and software, and 728 premium websites offering content of the same type. We then contribute domain-, content-, and risk-level analysis, examining and contrasting the websites' domain names, creation times, SSL certificates, HTTP requests, page size, average load time, and content type. For risk analysis, we consider and examine the maliciousness of these websites at the website- and component-level. Among other interesting findings, we show that free content websites tend to be vastly distributed across the TLDs and exhibit more dynamics with an upward trend for newly registered domains. Moreover, the free content websites are 4.5 times more likely to utilize an expired certificate, 19 times more likely to be malicious at the website level, and 2.64 times more likely to be malicious at the component level. Encouraged by the clear differences between the two types of websites, we explore the automation and generalization of the risk modeling of the free content risky websites, showing that a simple machine learning-based technique can produce 86.81\% accuracy in identifying them.

Yiyi Chen, Johannes Bjerva

Colexification refers to linguistic phenomena where multiple concepts (meanings) are expressed by the same lexical form, such as polysemy or homophony. Colexifications have been found to be pervasive across languages and cultures. The problem of concreteness/abstractness of concepts is interdisciplinary, studied from a cognitive standpoint in linguistics, psychology, psycholinguistics, neurophysiology, etc. In this paper, we hypothesize that concepts that are closer in concreteness/abstractness are more likey to colexify, and we test the hypothesis across indigenous languages in Americas.

Adam S. Grabell, Adrelys Mateo Santana, Kari N. Thomsen et al.

Limbic-prefrontal connectivity during negative emotional challenges underpins a wide range of psychiatric disorders, yet the early development of this system is largely unknown due to difficulties imaging young children. Functional Near-Infrared Spectroscopy (fNIRS) has advanced an understanding of early emotion-related prefrontal activation and psychopathology, but cannot detect activation below the outer cortex. Galvanic skin response (GSR) is a sensitive index of autonomic arousal strongly influenced by numerous limbic structures. We recorded simultaneous lateral prefrontal cortex (lPFC) activation via fNIRS and GSR in 73 3- to 5-year-old children, who ranged from low to severe levels of irritability, during a frustration task. The goal of the study was to test how frustration-related PFC activation modulated psychophysiology in preschool children, and whether associations were moderated by irritability severity. Results showed lPFC activation significantly increased, and GSR levels significantly decreased, as children moved from frustration to rest, such that preschoolers with the highest activation had the steepest recovery. Further, this relation was moderated by irritability such that children with severe irritability showed no association between lPFC activation and GSR. Results suggest functional connections between prefrontal and autonomic nervous systems are in place early in life, with evidence of lPFC down-regulation of frustration-based stress that is altered in early psychopathology. Combining fNIRS and GSR may be a promising novel approach for inferring limbic-PFC processes that drive early emotion regulation and psychopathology.

Wanxia Xiong, Min Wei, Li Zhang et al.

Abstract Background The pathogenesis of neuropathic pain (NP) has not been fully elucidated. Gene changes in dorsal root ganglia (DRG) may contribute to the development of NP. Circular RNAs (circRNAs) are a class of endogenous noncoding RNAs that form covalently closed loop structures and are crucial for genetic and epigenetic regulation. However, little is known about circRNA changes in DRG neurons after peripheral nerve injury. Methods A sciatic nerve chronic constriction injury (CCI) model was established to induce neuropathic pain. We performed genome-wide circRNA analysis of four paired dorsal root ganglion (DRG) samples (L4–L5) from CCI and negative control (NC) rats using next-generation sequencing technology. The differentially expressed circRNAs (DEcircRNAs) were identified by differential expression analysis, and the expression profile of circRNAs was validated by quantitative PCR. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to predict the function of DEcircRNAs. Results A total of 374 DEcircRNAs were identified between CCI and NC rats using circRNA high-throughput sequencing. Among them, 290 were upregulated and 84 were downregulated in the CCI group. The expression levels of nine DEcircRNAs were validated by qPCR. Functional annotation analysis showed that the DEcircRNAs were mainly enriched in pathways and functions, including ‘dopaminergic synapse,’ ‘renin secretion,’ ‘mitogen-activated protein kinase signaling pathway,’ and ‘neurogenesis.’ Competing endogenous RNA analysis showed that the top 50 circRNAs exhibited interactions with four pain-related microRNAs (miRNAs). Circ:chr2:33950934–33955969 was the largest node in the circRNA–miRNA interaction network. Conclusions Peripheral nerve injury-induced neuropathic pain led to changes in the comprehensive expression profile of circRNAs in the DRG of rats. DEcircRNAs may advance our understanding of the molecular mechanisms underlying neuropathic pain.

Carlos Bibián, N. Irastorza-Landa, M. Schönauer et al.