Intrinsic Scale Research Articles

Dynamics of seaweed-inspired piezoelectric plates for energy harvesting from oscillatory cross flow

Inspired by the vibrations of aquatic plants such as seaweed in the unsteady flow fields generated by free-surface waves, we investigate a novel device based on piezoelectric plates to harvest energy from oscillatory cross flows. Towards this end, numerical studies are conducted using a flow-structure-electric interaction model to understand the underlying physical mechanisms involved in the dynamics and energy harvesting performance of one or a pair of piezoelectric plates in an oscillatory cross flow. In a single-plate configuration, both periodic and irregular responses have been observed depending on parameters such as normalized plate stiffness and Keulegan–Carpenter number. Large power harvesting is achieved with the excitation of natural modes. Besides, when the time scale of the motion and the intrinsic time scale of the circuit are close to each other the power extraction is enhanced. In a two-plate configuration with tandem formation, the hydrodynamic interaction between the two plates can induce irregularity in the response. In terms of energy harvesting, two counteracting mechanisms have been identified, shielding and energy recovery. The shielding effect reduces plate motion and energy harvesting, whereas with the energy recovery effect one plate is able to recovery energy from the wake of another for performance enhancement. The competition between these mechanisms leads to constructive or destructive interactions between the two plates. These results suggest that for better performance the system should be excited at its natural period, which should be close to the intrinsic time scale of the circuit. Moreover, using a pair of plates in a tandem formation can further improve the energy harvesting capacity when conditions for constructive interaction are satisfied.

Noncovalent and Covalent O-H···O Interactions in PPh3O Cocrystals: A Correlation Study Involving QTAIM, SAPT, NBO, and IBSI Methods.

PPh3O.hemihydrate polymorphs and 11 assorted PPh3O cocrystals collectively constitute a reliable stock to pursue a systematic analysis aiming to investigate the impacts of some vital issues on the TPPO.H-bond donor aggregates. The issues highlighted herein are (i) effect of varying acidity of H-bond donors on the degeneracy of lone pairs of the H-bond acceptor (PPh3O), (ii) effectiveness of the |V(r)|/G(r) and H(r)/ρ(r) parameters as a covalency metric, (iii) 3c-4e bonding in the covalent PPh3O.nitric acid cocrystal, (iv) salient features of H-bond interaction energy and an interplay of its components, (v) an intrinsic bond strength scale for the PPh3O cocrystals, and (vi) reliable empirical relations between several bond descriptors for a quick estimation of interaction energy. To be specific about point (vi), we have propounded two promising avenues for a fast semiquantitative calculation of interaction energy from an endearing nonenergetic parameter, viz., bond length: dO-H···O → ρBCP (MAPE = 2.36%) → ESAPT0 (MAPE = 9.26%), and dO-H···O → IBSI (MAPE = 1.87%) → ESAPT0 (MAPE = 9.66%). All the aforesaid issues have been explored in detail through the QTAIM, NBO, and IBSI analyses (M06-2X-D3/def2-TZVP level), as well as by the SAPT study at the SAPT0/aug-cc-pVDZ platform. The statistically valid correlation studies can be particularly conducive for practical purposes as a transformative extension of the established facts into postulates for the unknown cocrystals.

A multiscale symbolic approach to decoding delta and ripple oscillation bands as biomarkers for epileptiform discharges.

We use a multiscale symbolic approach to study the complex dynamics of temporal lobe refractory epilepsy employing high-resolution intracranial electroencephalogram (iEEG). We consider the basal and preictal phases and meticulously analyze the dynamics across frequency bands, focusing on high-frequency oscillations up to 240 Hz. Our results reveal significant periodicities and critical time scales within neural dynamics across frequency bands. By bandpass filtering neural signals into delta, theta, alpha, beta, gamma, and ripple high-frequency bands (HFO), each associated with specific neural processes, we examine the distinct nonlinear dynamics. Our method introduces a reliable approach to pinpoint intrinsic time lag scales τ within frequency bands of the basal and preictal signals, which are crucial for the study of refractory epilepsy. Using metrics such as permutation entropy (H), Fisher information (F), and complexity (C), we explore nonlinear patterns within iEEG signals. We reveal the intrinsic τmax that maximize complexity within each frequency band, unveiling the nonlinear subtle patterns of the temporal structures within the basal and preictal signal. Examining the H×F and C×F values allows us to identify differences in the delta band and a band between 200 and 220 Hz (HFO 6) when comparing basal and preictal signals. Differences in Fisher information in the delta and HFO 6 bands before seizures highlight their role in capturing important system dynamics. This offers new perspectives on the intricate relationship between delta oscillations and HFO waves in patients with focal epilepsy, highlighting the importance of these patterns and their potential as biomarkers.

Can Inexperienced Listeners Hear Who Is Singing? The Role of Motivation in Singer Discrimination Across Pitch

Previous research has shown that in a task identifying singers across pitch, inexperienced listeners perform very poorly compared to their experienced counterparts. This poor performance may partially be due to lower motivation and reduced attention on the part of inexperienced listeners. The current experiment is designed to examine the role of motivation in difficult perceptual tasks through use of an established methodology that uses singing voice stimuli. This study used an ABX paradigm. Listeners heard two different singers, singing /ɑ/ at the same pitch and had to identify which of the two singers produced a third /ɑ/ at a different pitch. Pitches varied across 1.5 octaves. Inexperienced listeners were randomly assigned to 1 of 3 conditions: (1) no feedback, (2) percent correct feedback, and (3) percentile feedback. Prior to the experiment, listeners rated their motivation using the Situational Intrinsic Motivation Scale (SIMS). Data were collected from 99 inexperienced listeners. There were no significant differences between the three feedback conditions, No Feedback, Percent Correct, and Percentile, for any SIMS subscale. Likewise, there were no significant differences in musical experience between the three feedback conditions. A repeated measures ANOVA designed to test the effect of feedback group on mean percent correct responses revealed no significant main or interaction effects of feedback. However, amotivation was a significant predictor of mean percent correct scores. Motivation is a complex construct that, while not being a primary factor in the current audio-perceptual task, could still be an important confounding factor in perceptual research. In the case of the current study, the two feedback conditions utilized in this study, Percent Correct and Percentile, may not have provided sufficiently robust external motivation to elicit differences in performance. Perceptual and behavioral researchers should be vigilant. More research is necessary.

The Correlation Between Eighth-Grade Students’ Metacognitive Reading Awareness, Reading Intrinsic Motivation, and Reading Habits

Reading, which improves language and mental skills, is the most effective way to reach information from the past to the present. The study tried to determine the relationship between the metacognitive reading awareness, reading intrinsic motivations, and reading motivations of eighth-grade students. The study group consists of 132 eighth-grade students in a secondary school in the Battalgazi district of Malatya province—the research design is a relational screening model. The metacognitive reading awareness scale,” “Intrinsic Reading Motivation Scale,” and “Book Reading Habit Scale” were used as data collection tools. As a result of the analyses, the students got moderate scores from the metacognitive reading awareness, intrinsic motivation, and book reading habit scales. Moreover, no notable difference was found in students’ metacognitive reading strategies, reading motivations, and reading habits according to gender. The study suggests no significant link exists between “metacognitive reading awareness” and “intrinsic motivation to read,” based on the correlation analysis conducted on the three scales. Nonetheless, there were exceptionally high positive correlations among the sub-dimensions of the scales.

New expanding cavity model for conical indentation and its application to determine an intrinsic length scale of polymeric materials

New expanding cavity model for conical indentation and its application to determine an intrinsic length scale of polymeric materials

Analysis of changes in intrinsic neural timescales in male smoking addicts based on whole brain resting-state functional magnetic resonance imaging

Objective: To investigate the abnormal changes of intrinsic neural time scale (INT) in male smoking addicts based on whole brain resting state functional magnetic resonance imaging (rs-fMRI). Methods: A case-control study. The clinical data and whole brain rs-fMRI data of 139 male subjects, aged (34.1±8.8) years, recruited through the online platform from January 2019 to December 2021 were retrospectively analyzed. According to the existence of smoking addiction, they were divided into smoking addiction group (n=83) and healthy control group (n=56).INT was calculated to reflect the brain neural activity dynamics. Single sample t test was used to obtain the whole brain spatial distribution maps of INT in smoking addiction group and the control group. Then two-sample t test was conducted to explore the difference of INT between the smoking addition group and the healthy control group, with age and years of education as covariates. Finally, Spearman correlation analysis was used to explore the relationship between INT and nicotine dependence scale score and smoking index. Results: Subjects with smoking addiction and healthy control group showed a similar pattern of hierarchical neural timescales, namely shorter INT in sensorimotor areas and longer INT in parietal lobe, posterior cingulate cortex. In addition, in the smoking addiction group, the left medial occipital gyrus (peak t=-3.18), left suproccipital gyrus (peak t=-3.66), bilateral pericalar cleft cortex (left: peak t=-3.02, right: peak t=-3.22), bilateral lingual gyrus (left: peak t=-3.10, right: t peak=-3.04), left cuneus (peak t=-2.97), default network associated brain region [left anterior cuneus(peak t=-3.23), left angular gyrus (peak t=-3.07), and left posterior cingulate cortex (peak t=-3.54) were significantly lower than those of healthy controls (gaussian random field correction, voxel level all P<0.005, mass level all P<0.05). However, there was no significant correlation between INT and nicotine dependence scale score and smoking index (both P>0.05 after Bonferroni correction). Conclusion: Compared with healthy controls, smoking addicts showed abnormal changes in the dynamics of neural activity in the visual cortex and the default network.

Ultrafast atomic-scale scanning tunnelling spectroscopy of a single vacancy in a monolayer crystal

Defects in atomically thin semiconductors and their moiré heterostructures have emerged as a unique testbed for quantum science. Strong light–matter coupling, large spin–orbit interaction and enhanced Coulomb correlations facilitate a spin–photon interface for future qubit operations and efficient single-photon quantum emitters. Yet, directly observing the relevant interplay of the electronic structure of a single defect with other microscopic elementary excitations on their intrinsic length, time and energy scales remained a long-held dream. Here we directly resolve in space, time and energy how a spin–orbit-split energy level of an isolated selenium vacancy in a moiré-distorted WSe2 monolayer evolves under the controlled excitation of lattice vibrations, using lightwave scanning tunnelling microscopy and spectroscopy. By locally launching a phonon oscillation and taking ultrafast energy-resolved snapshots of the vacancy’s states faster than the vibration period, we directly measure the impact of electron–phonon coupling in an isolated single-atom defect. The combination of atomic spatial, sub-picosecond temporal and millielectronvolt energy resolution marks a disruptive development towards a comprehensive understanding of complex quantum materials, where the key microscopic elementary interactions can now be disentangled, one by one.

Probing active nematics with in situ microfabricated elastic inclusions

In this work, we report a direct measurement of the forces exerted by a tubulin/kinesin active nematic gel as well as its complete rheological characterization, including the quantification of its shear viscosity, η, and its activity parameter, α. For this, we develop a method that allows us to rapidly photo-polymerize compliant elastic inclusions in the continuously remodeling active system. Moreover, we quantitatively settle long-standing theoretical predictions, such as a postulated relationship encoding the intrinsic time scale of the active nematic in terms of η and α. In parallel, we infer a value for the nematic elasticity constant, K, by combining our measurements with the theorized scaling of the active length scale. On top of the microrheology capabilities, we demonstrate strategies for defect encapsulation, quantification of defect mechanics, and defect interactions, enabled by the versatility of the microfabrication strategy that allows to combine elastic motifs of different shapes and stiffnesses that are fabricated in situ.

EEG-based finger movement classification with intrinsic time-scale decomposition.

Brain-computer interfaces (BCIs) are systems that acquire the brain's electrical activity and provide control of external devices. Since electroencephalography (EEG) is the simplest non-invasive method to capture the brain's electrical activity, EEG-based BCIs are very popular designs. Aside from classifying the extremity movements, recent BCI studies have focused on the accurate coding of the finger movements on the same hand through their classification by employing machine learning techniques. State-of-the-art studies were interested in coding five finger movements by neglecting the brain's idle case (i.e., the state that brain is not performing any mental tasks). This may easily cause more false positives and degrade the classification performances dramatically, thus, the performance of BCIs. This study aims to propose a more realistic system to decode the movements of five fingers and the no mental task (NoMT) case from EEG signals. In this study, a novel praxis for feature extraction is utilized. Using Proper Rotational Components (PRCs) computed through Intrinsic Time Scale Decomposition (ITD), which has been successfully applied in different biomedical signals recently, features for classification are extracted. Subsequently, these features were applied to the inputs of well-known classifiers and their different implementations to discriminate between these six classes. The highest classifier performances obtained in both subject-independent and subject-dependent cases were reported. In addition, the ANOVA-based feature selection was examined to determine whether statistically significant features have an impact on the classifier performances or not. As a result, the Ensemble Learning classifier achieved the highest accuracy of 55.0% among the tested classifiers, and ANOVA-based feature selection increases the performance of classifiers on five-finger movement determination in EEG-based BCI systems. When compared with similar studies, proposed praxis achieved a modest yet significant improvement in classification performance although the number of classes was incremented by one (i.e., NoMT).

Analysis of size-dependent response of surface excited functionally graded layer with consideration of couple-stress effects

This paper focuses on a theoretical examination of the mechanical behavior of elastic layers made of functionally graded (FG) materials. It particularly highlights the impact of material microstructures by utilizing the couple stress theory to introduce FG characteristics of the coating material across the thickness direction, along with size effects. The study distinctively addresses both surface loading and contact problems, employing various indenter shapes and eccentric indentation forces. The Fourier transform is utilized to solve for displacements and stress fields resulting from surface tractions. The method for approximating the pressure distribution under the indenter is based on a collocation method with a simple discretization of the contact pressure. Brent's method is applied to determine the unknown contact region when using indenters with non-sharp edges. The results demonstrate that the shear modulus ratio and the intrinsic material length scale significantly influence the pressure intensity, highlighting a substantial dependence on the mechanical properties of materials under indentation force. The research also shows that the effect of the length scale and shear modulus ratio affects the limit eccentricity and tilt angle. The results highlight the necessity of considering both the size effect and material gradation when analyzing FG materials under mechanical stress.

Role of Human Resource Management Value-Added on Financial Performance Efficiency Management: The Mediating Role of Employee Commitment

This study explores the interconnections among transformational leadership, employee motivation, employee commitment, and financial management efficiency in the Central Sulawesi banking sector, Indonesia. It aims to uncover how transformational leadership and employee motivation impact a company's financial management efficiency and assesses the mediating function of employee commitment in this context. The research encompasses a sample of 396 employees drawn from various Central Sulawesi banks, selected via convenient sampling. Inclusion criteria encompassed a minimum one-year tenure at their current organization and direct exposure to their superiors' leadership styles and familiarity with financial management practices. Data collection entailed a self-administered questionnaire comprising four sections. The first segment gathered demographic data, including age, gender, education, job position, and tenure. The second assessed transformational leadership, employing adapted items from the Multifactor Leadership Questionnaire (MLQ). It scrutinized idealized influence, inspirational motivation, intellectual stimulation, and individualized consideration. The third section gauged employee motivation, adapting items from the Work Extrinsic and Intrinsic Motivation Scale (WEIMS), covering extrinsic and intrinsic motivation factors. The fourth section measured financial performance efficiency, considering metrics such as stock price, firm innovativeness, and learning orientation. It also assessed employee commitment, comprising affective, continuance, and normative commitment. Responses utilized a Likert-type scale from 1 (strongly disagree) to 5 (strongly agree). A pilot test ascertained questionnaire clarity and comprehensibility. The findings illuminate the intricate web of factors impacting financial management efficiency, underscoring employee motivation and transformational leadership's pivotal roles, mediated by employee commitment. This study enriches practical and theoretical understanding, offering invaluable insights for leaders, managers, and researchers striving to enhance financial management efficiency and organizational performance.

Validation of an eight-item resilience scale for inpatients with spinal cord injuries in a rehabilitation hospital: exploratory factor analyses and item response theory

Purpose People with spinal cord injury (PwSCI) can experience life changes, including impacts on their physical and mental health. PwSCI often report less life satisfaction and lower subjective well-being than peers without SCI. These challenges and adversities increase the demand on them to be more resilient. Healthcare providers need quick and valid instruments to assess adult patients’ resilience in clinical settings. We aimed to validate the factor validity and discrimination ability of a resilience scale, CD-RISC-10, for clinical usage in adults with SCI during hospitalization. Materials and Methods 93 adults with SCI responded to the self-reported survey, including CD-RISC-10, the Patient Health Questionnaire-9 Scale (PHQ-9), the Satisfaction with Life Scale (SWLS), and the Intrinsic Spirituality Scale. We conducted descriptive statistics, exploratory factor analysis (EFA), and item response theory (IRT). Results Two items were deleted from CD-RISC-10 after EFA, forming CD-RISC-8. The item discriminations of the remaining eight items from the unconstrained IRT model ranged from a high of 3.071 to a relatively low 1.433. CD-RISC-8 is significantly related to PHQ-9 and SWLS. Conclusions The factor validity of the CD-RISC-8 was improved. Significantly, the CD-RISC-8 has excellent potential for clinical usage due to its discriminant ability between low and intermediate resilience.

Differences in Intrinsic and Extrinsic Motivation and Obsessive-Compulsive Symptoms among High School Students in light of Some Variables

The present study investigated whether there are differences in intrinsic and extrinsic motivation and obsessive-compulsive symptoms by gender, academic stream and grade level. The sample of the study consisted of 512 high school students in Northern Almazar District, Jordan. Data were collected using three scales measuring intrinsic and extrinsic motivation and obsessive-compulsive symptoms. Three-way ANOVA, and three-way MANOVA were used. This study used an analytical-descriptive methodology. Results showed that males scored significantly higher on the intrinsic motivation scale, scientific stream students scored significantly higher on the intrinsic motivation scale, literary stream students scored significantly higher on the extrinsic motivation scale, twelfth grade students scored significantly higher on the extrinsic motivation scale, literary stream students scored significantly higher on the slowness subscale of the obsessive-compulsive scale, and twelfth grade students scored significantly higher on the doubting subscale of the obsessive-compulsive scale.

Beam-type acoustic black holes incorporating the microstructure-dependent nonlocal effect

Acoustic black holes (ABHs) are effective passive damping structures for capturing bending waves at wedge edges. However, as the wedge shape continuously reduces in size, the intrinsic length scale of the ABH's tip gradually approaches the external length scale, such as the wavelength of wave, which causes a phenomenon known as the "scale effect" to take hold of the ABH. Despite gaining considerable attention in the past two decades, the influence of intrinsic length on the energy aggregation of ABHs has not been thoroughly investigated. This study aims to explore the significant contribution of microstructure-dependent nonlocal effects on the dynamic behavior of ABHs, which holds great scientific importance. The nonlocality arises from the inherent length of the material being studied. A nonlocal elastic theory (NET) is employed to model the dynamic behavior of one-dimensional ABH beams. Geometric acoustic method is proposed to analyze the power-law beam wave number and microstructure-related reflection coefficient. Results indicate a significant impact of nonlocality on the acoustic energy of beam-type ABHs, particularly when the nonlocal intrinsic length approaches the truncation length of the wedge. Moreover, a comparison between the present study and classical theory reveals an overestimation of the reflection coefficient in conventional works for small truncation lengths. The relationship between the reflection coefficient, truncation length, and nonlocal characteristic lengths is thoroughly examined. Additionally, the influence of the damping layer and different power-law exponents m on ABH behavior is extensively studied.

Cross-National Measurement of Mathematics Intrinsic Motivation: An Investigate of Measurement Invariance with MG-CFA and Aligment Method Across Fourteen Countries

One of the main objectives of international large-scale assessments is to make comparisons between different countries, education policies, education systems, or subgroups. One of the main criteria for making comparisons between different groups is to ensure measurement invariance. The purpose of this study was to test the measurement invariance of the mathematics intrinsic motivation scale across 14 countries. For this purpose, the "students like learning mathematics" scale, which measures intrinsic motivation for mathematics, was included in the TIMSS 2019 cycle. The study sample consisted of a total of 152992 students, 70192 4th grade and 82800 8th grade students from 14 different countries participating in the TIMSS 2019 cycle. Measurement invariance was tested with Multi-Group Confirmatory Factor Analysis (MG-CFA) and Alignment Method. The mathematics intrinsic motivation scale provides only configural invariance according to MG-CFA at the 4th grade level, whereas the scale provides approximate invariance according to the alignment method. At the 8th grade level, the scale provides configural and metric invariance according to MG-CFA, whereas the scale provides approximate invariance according to the alignment method. The results indicate that the mathematics intrinsic motivation scale provides approximate measurement invariance at both grade levels and that comparisons can be made between the scores of the identified countries.

Task-Based Instruction in Enhancing Conversational Skills of Thai Students at Grade 11, YouTube as Teaching Media

Students' English communication abilities in Thailand remain poor due to a lack of a wide range of activities to practice English. Learning English in authentic contexts enables students to develop intrinsic motivation and demonstrate acquired language competency. This study aims to enhance English conversational performances and investigate students' motivation after receiving instruction by integrating TBI and YouTube. The design of this study was pre-experimental research, which used the one-group and pretest-posttest analysis. The sample group included 39 eleventh-grade students from a government senior high school in Mahasarakham province, Thailand chosen by a purposive sampling process. The listening and speaking tests, as well as the intrinsic motivation scale, were used in this study. Data were analyzed by the paired-sample t-test and descriptive statistics (i.e., the arithmetic mean, standard deviation, and percentage). The results revealed that combining TBI with YouTube improved students' English communication skills, and intrinsic motivation in learning. Based on the findings of this study, the researchers recommended that teachers employ the TBL approach and YouTube videos in class as instructional mediums. Furthermore, future studies could combine TBL with other forms of multimedia to help students learn more effectively and enjoyably.

Linking intrinsic scales of ecological processes to characteristic scales of biodiversity and functioning patterns

Ecology is a science of scale, which guides our description of both ecological processes and patterns, but we lack a systematic understanding of how process scale and pattern scale are connected. Recent calls for synthesis between population ecology, community ecology, and ecosystem ecology motivate the integration of phenomena at multiple organizational levels. Furthermore, many studies leave out the scaling of a critical process: species interactions, which may be non‐local through movement or foraging and must be distinguished from dispersal scales. Here, we use simulations to explore the consequences of three different process scales (species interactions, dispersal, and the environment) on emergent patterns of biodiversity, ecosystem functioning, and their relationship, in a spatially‐explicit landscape and stable equilibrium setting. A major result of our study is that the spatial scales of dispersal and species interactions have opposite effects: a larger dispersal scale homogenizes spatial biomass patterns, while a larger interaction scale amplifies their heterogeneity. Interestingly, the specific scale at which dispersal and interaction scales begin to influence landscape patterns depends on the scale of environmental heterogeneity – in other words, the scale of one process allows important scales to emerge in other processes. This interplay between process scales, i.e. a situation where no single process dominates, can only occur when the environment is heterogeneous and the scale of dispersal small. Finally, contrary to our expectations, we observe that the spatial scale of ecological processes is more clearly reflected in landscape patterns (i.e. distribution of local outcomes) than in global patterns such as species–area relationships (SARs) or large‐scale biodiversity–functioning relationships. Overall we conclude that long‐range interactions often act differently and even in opposite ways to dispersal, and that the landscape patterns that emerge from the interplay of long‐ranged interactions, dispersal and environmental heterogeneity are not well captured by often‐used metrics like the SAR.

Influence of teacher autonomy support in feedback on high school students' feedback literacy: the multiple mediating effects of basic psychological needs and intrinsic motivation.

This research presents and confirms an intermediary model, deeply anchored in self-determination theory, to dissect the influence of Chinese high school students' core psychological needs and intrinsic drive on the nexus between educators' autonomous backing and students' proficiency in feedback literacy, highlighting the mediating roles of these elements. A survey of 704 Chinese senior high school students, including 319 males and 385 females, employed the Feedback Literacy Scale, Basic Psychological Needs Scale, Intrinsic Motivation Scale, and Perceived Teacher Autonomy Support Scale. The study's discoveries illuminate that educators' autonomous support not only directly amplifies students' feedback literacy but also has an indirect impact through the intermediation of basic psychological needs and intrinsic motivation, along with their interconnected dynamics. This inquiry not only deepens our grasp of the mechanisms interlinking teacher support with feedback literacy but also critically evaluates the findings to proffer targeted recommendations, thereby enhancing our comprehension of the underlying processes and guiding educational practices and student development.

Fibrotaxis: gradient-free, spontaneous and controllable droplet motion on soft solids

Most passive droplet transport strategies rely on spatial variations of material properties to drive droplet motion, leading to gradient-based mechanisms with intrinsic length scales that limit the droplet velocity or...