Behavioral Output Research Articles

Hierarchical Integration of Organic Core/Shell Microwires for Advanced Photonics

AbstractThe combination of multiple components or structures into integrated micro/nanostructures for practical application has been pursued for many years. Herein, a series of hierarchical organic microwires with branch, core/shell (C/S), and branch C/S structures are successfully constructed based on organic charge transfer (CT) cocrystals with structural similarity and physicochemical tunability. By regulating the intermolecular CT interaction, single microwires and branch microstructures can be integrated into the C/S and branch C/S structures, respectively. Significantly, the integrated branch C/S microwires, with multicolor waveguide behavior and branch structure multichannel waveguide output characteristics, can function as an optical logic gate with multiple encoding features. This work provides useful insights for creating completely new types of organic microstructures for integrated optoelectronics.

Glial regulators of ions and solutes required for specific chemosensory functions in Caenorhabditis elegans.

Glia and accessory cells regulate the microenvironment around neurons and primary sensory cells. However, the impact of specific glial regulators of ions and solutes on functionally diverse primary cells is poorly understood. Here, we systemically investigate the requirement of ion channels and transporters enriched in Caenorhabditis elegans Amsh glia for the function of chemosensory neurons. Although Amsh glia ablated worms show reduced function of ASH, AWC, AWA, and ASE neurons, we show that the loss of glial enriched ion channels and transporters impacts these neurons differently, with nociceptor ASH being the most affected. Furthermore, our analysis underscores the importance of K+, Cl-, and nucleoside homeostasis in the Amphid sensory organ and uncovers the contribution of glial genes implicated in neurological disorders. Our findings build a unique fingerprint of each glial enriched ion channel and transporter and may provide insights into the function of supporting cells of mammalian sensory organs.

The topological space of subjective experience.

Subjective experiences often feel rich, yet are most often quantified with simple metrics, such as a few levels on a predefined scale. What are the dimensions and topological organization of subjective experience? How do they relate to behavioral output? And how do they map onto the classical cognitive domains?

What evidence is there for implicating the brain orexin system in neuropsychiatric symptoms in dementia?

Neuropsychiatric symptoms (NPS) affect people with dementia (PwD) almost universally across all stages of the disease, and regardless of its exact etiology. NPS lead to disability and reduced quality of life of PwD and their caregivers. NPS include hyperactivity (agitation and irritability), affective problems (anxiety and depression), psychosis (delusions and hallucinations), apathy, and sleep disturbances. Preclinical studies have shown that the orexin neuropeptide system modulates arousal and a wide range of behaviors via a network of axons projecting from the hypothalamus throughout almost the entire brain to multiple, even distant, regions. Orexin neurons integrate different types of incoming information (e.g., metabolic, circadian, sensory, emotional) and convert them into the required behavioral output coupled to the necessary arousal status. Here we present an overview of the behavioral domains influenced by the orexin system that may be relevant for the expression of some critical NPS in PwD. We also hypothesize on the potential effects of pharmacological interference with the orexin system in the context of NPS in PwD.

A wavelet-based dynamic mode decomposition for modeling mechanical systems from partial observations

Dynamic mode decomposition (DMD) has emerged as a popular data-driven modeling approach to identifying spatio-temporal coherent structures in dynamical systems, owing to its strong relation with the Koopman operator. For dynamical systems with external forcing, the identified model should not only be suitable for a specific forcing function but should generally approximate the input–output behavior of the underlying dynamics. A novel methodology for modeling those classes of dynamical systems is proposed in the present work, using wavelets in conjunction with the input–output dynamic mode decomposition (ioDMD). The wavelet-based dynamic mode decomposition (WDMD) builds on the ioDMD framework without the restrictive assumption of full state measurements. Our non-intrusive approach constructs numerical models directly from trajectories of the full model’s inputs and outputs, without requiring the full-model operators. These trajectories are generated by running a simulation of the full model or observing the original dynamical systems’ response to inputs in an experimental framework. Hence, the present methodology is applicable for dynamical systems whose internal state vector measurements are not available. Instead, data from only a few output locations are only accessible, as often the case in practice. The present methodology’s applicability is explained by modeling the input–output response of an Euler–Bernoulli finite element beam model. The WDMD provides a linear state-space representation of the dynamical system using the response measurements and the corresponding input forcing functions. The developed state-space model can then be used to simulate the beam’s response towards different types of forcing functions. The method is further validated on a real (experimental) data set using modal analysis on a simple free–free beam, demonstrating the efficacy of the proposed methodology as an appropriate candidate for modeling practical dynamical systems despite having no access to internal state measurements and treating the full model as a black-box.

Wear and triboelectric performance of polymers with non-polar lubricants

Triboelectric nanogenerators (TENGs) convert kinetic energy into electrical energy based on triboelectrification and electrostatic induction. There are many benefits to TENGs, such as inexpensiveness, processability, and high applicability. However, friction and wear, in solid–solid contact TENGs, affect their lifespans. In this study, we evaluated the tribological behavior and electrical output of polymers in TENG systems with non-polar lubricants reducing friction and wear. The lubricant-dependent tribological behavior of polymers was influenced by the viscosity of lubricants and the wetting and mechanical characteristics of polymers. Furthermore, the electrical outputs of lubricant-based TENG system were improved and powered the electronic device. The comprehensive analysis on tribological behavior of lubricant-based TENGs in this study contributes to promote the reliability of lubricant-based TENG system.

Alterations of presynaptic proteins in autism spectrum disorder.

The expanded use of hypothesis-free gene analysis methods in autism research has significantly increased the number of genetic risk factors associated with the pathogenesis of autism. A further examination of the implicated genes directly revealed the involvement in processes pertinent to neuronal differentiation, development, and function, with a predominant contribution from the regulators of synaptic function. Despite the importance of presynaptic function in synaptic transmission, the regulation of neuronal network activity, and the final behavioral output, there is a relative lack of understanding of the presynaptic contribution to the pathology of autism. Here, we will review the close association among autism-related mutations, autism spectrum disorders (ASD) phenotypes, and the altered presynaptic protein functions through a systematic examination of the presynaptic risk genes relating to the critical stages of synaptogenesis and neurotransmission.

Cohesin Dependency in Npm1c/+ and Flt3-ITD Mutant Hematopoietic Stem and Progenitor Cells

Acute myeloid leukemia (AML) is an aggressive myeloid malignancy with high relapse (40-60%) and low median survival rate (5-7 months post treatment in relapse setting), particularly for patients over 65 years old. Genomic investigations of AML have identified recurrent mutations, such as FMS-like tyrosine kinase 3 (FLT3, 20-25%) and Nucleophosmin (NPM1, 30%). When mutated, FLT3 acquires an internal tandem duplication (FLT3-ITD) and causes aberrant STAT5/AKT signaling. For NPM1, mutation frequently occurs at nuclear export signal, which results in cytoplasmic localization (NPM1c). In AML, these driver mutations co-occur with other genetic lesions, particularly in epigenetic regulators. Clincally, patients with FLT3-ITD mutations have a very poor prognosis. While the pathophysiology is not completely understood, direct inhibition of FLT3 by tyrosine kinase inhibitors have, to-date, been underwhelming. In contrast, the NPM1c mutation in AML patients is favorable and chemotherapy sensitive when NPM1c is the sole driver mutation. Yet, co-mutation of NPM1c with other known AML mutations, such as Flt3-ITD, negates this favorable prognosis. STAG2 (Stromal Antigen 2) is a member of cohesin complex that is recurrently mutated in >10 cancers and is essential in maintaining the integrity of the 3-dimensional genome partitioning structure known as topologically structural domains (TADs). Previously, our work has demonstrated that depletion of various cohesin factors, including Stag2, leads to increased hematopoietic stem and progenitor cell (HSPC) self-renewal and myeloid-biased differentiation. Loss of Stag2 leads to impairment of sub-TADs and affects the capability of key hematopoietic transcription factors, such as PU.1, to access and engage their target genes. In the context of AML, disruption of TADs can lead to altered transcriptional output and cellular behavior. Mutation of STAG2 frequently arises in AML (16%) and co-occurs with NPM1 and FLT3 oncogenes. To examine the consequences of co-occurring Stag2/Npm1c or Stag2/Flt3-ITD mutations, we generated two compound mutant murine models crossed to conditional alleles of Stag2, Npm1c and constitutively active Flt3-ITD in the Ubc-CreER background. At 6-8 weeks of age, tamoxifen was administered to mice harboring Stag2/Npm1c or Stag2/Flt3-ITD mutations to delete Stag2 or activate Npm1c alleles respectively, while the Flt3-ITD mutation is active since birth. Immunophenotyping analysis was performed at 4 weeks post mutation activation in the bone marrow and peripheral blood. For mice carrying double Stag2/Npm1c mutation, there was no change in the number of stem cell population (HSCLT). In contrast, comparing to Npm1c/+ mice, Stag2-/-Npm1c/+ mice had an elevated myeloid-biased multipotent progenitor population (MPP3, LSK flk2- CD150- CD48+). However, there was no change in granulocyte-monocyte progenitor (GMP) number (Figure 1A). To determine if the myeloid bias was due to lack of the entire cohesin complex, we generated the Smc3/Npm1c mutant mice, where both Stag1-cohesin and Stag2-cohesin complexes were partially depleted upon heterozygous deletion of Smc3. Interestingly, there were no changes in MPP3 population in Smc3+/-Npm1c/+ mice, pointing to a Stag2-cohesin specific phenomenon. In the Stag2/Flt3-ITD co-mutation model, loss of Stag2-cohesin resulted in no changes in MPP3 cells compared to monogenic Flt3-ITD mutation. However, we did observe a normalization of GMPs, suggesting that Stag2-cohesin loss is crucial for abnormal myeloid differentiation in Flt3-ITD background (Figure 1B). In order to evaluate whether the order of mutations impacted immunophenotypic aberrancy, we additionally generated a stepwise Stag2/Flt3-ITD mutational model by deleting Stag2 first (via Mx1-Cre) for 4 weeks followed by tamoxifen-inducible Frt activated Flt3-ITD mutation (Flt3 frt-ITD/+) for 4 weeks. Interestingly, there was no difference in the normalization effect between constitutive and conditional activation of Flt3-ITD mutation, suggesting the loss of Stag2-cohesin is not required prior to Flt3-ITD acquisition. Further characterization of these co-mutational murine models is in progress. With these models, we aim to uncover the dependency of Stag2-cohesin in leukemia maintenance. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Sexually dimorphic architecture and function of a mechanosensory circuit in C. elegans

How sensory perception is processed by the two sexes of an organism is still only partially understood. Despite some evidence for sexual dimorphism in auditory and olfactory perception, whether touch is sensed in a dimorphic manner has not been addressed. Here we find that the neuronal circuit for tail mechanosensation in C. elegans is wired differently in the two sexes and employs a different combination of sex-shared sensory neurons and interneurons in each sex. Reverse genetic screens uncovered cell- and sex-specific functions of the alpha-tubulin mec-12 and the sodium channel tmc-1 in sensory neurons, and of the glutamate receptors nmr-1 and glr-1 in interneurons, revealing the underlying molecular mechanisms that mediate tail mechanosensation. Moreover, we show that only in males, the sex-shared interneuron AVG is strongly activated by tail mechanical stimulation, and accordingly is crucial for their behavioral response. Importantly, sex reversal experiments demonstrate that the sexual identity of AVG determines both the behavioral output of the mechanosensory response and the molecular pathways controlling it. Our results present extensive sexual dimorphism in a mechanosensory circuit at both the cellular and molecular levels.

Human thirst behavior requires transformation of sensory inputs by intrinsic brain networks

BackgroundTo survive and thrive, many animals, including humans, have evolved goal-directed behaviors that can respond to specific physiological needs. An example is thirst, where the physiological need to maintain water balance drives the behavioral basic instinct to drink. Determining the neural basis of such behaviors, including thirst response, can provide insights into the way brain-wide systems transform sensory inputs into behavioral outputs. However, the neural basis underlying this spontaneous behavior remains unclear. Here, we provide a model of the neural basis of human thirst behavior.ResultsWe used fMRI, coupled with functional connectivity analysis and serial-multiple mediation analysis, we found that the physiological need for water is first detected by the median preoptic nucleus (MnPO), which then regulates the intention of drinking via serial large-scale spontaneous thought-related intrinsic network interactions that include the default mode network, salience network, and frontal-parietal control network.ConclusionsOur study demonstrates that the transformation in humans of sensory inputs for a single physiological need, such as to maintain water balance, requires large-scale intrinsic brain networks to transform this input into a spontaneous human behavioral response.

Virtual reality stimulation and organizational neuroscience for the assessment of empathy

This study aimed to evaluate the viability of a new procedure based on machine learning (ML), virtual reality (VR), and implicit measures to discriminate empathy. Specifically, eye-tracking and decision-making patterns were used to classify individuals according to their level in each of the empathy dimensions, while they were immersed in virtual environments that represented social workplace situations. The virtual environments were designed using an evidence-centered design approach. Interaction and gaze patterns were recorded for 82 participants, who were classified as having high or low empathy on each of the following empathy dimensions: perspective-taking, emotional understanding, empathetic stress, and empathetic joy. The dimensions were assessed using the Cognitive and Affective Empathy Test. An ML-based model that combined behavioral outputs and eye-gaze patterns was developed to predict the empathy dimension level of the participants (high or low). The analysis indicated that the different dimensions could be differentiated by eye-gaze patterns and behaviors during immersive VR. The eye-tracking measures contributed more significantly to this differentiation than did the behavioral metrics. In summary, this study illustrates the potential of a novel VR organizational environment coupled with ML to discriminate the empathy dimensions. However, the results should be interpreted with caution, as the small sample does not allow general conclusions to be drawn. Further studies with a larger sample are required to support the results obtained in this study.

AWC thermosensory neuron interferes with information processing in a compact circuit regulating temperature-evoked posture dynamics in the nematode Caenorhabditis elegans

Elucidating how individual neurons encode and integrate sensory information to generate a behavior is crucial for understanding neural logic underlying sensory-dependent behavior. In the nematode Caenorhabditis elegans, information flow from sensory input to behavioral output is traceable at single-cell level due to its entirely solved neural connectivity. C. elegans processes the temperature information for regulating behavior consisting of undulatory posture dynamics in a circuit including two thermosensory neurons AFD and AWC, and their postsynaptic interneuron AIY. However, how the information processing in AFD-AWC-AIY circuit generates the posture dynamics remains elusive. To quantitatively evaluate the posture dynamics, we introduce locomotion entropy, which measures bandwidth of the frequency spectrum of the undulatory posture dynamics, and assess how the motor pattern fluctuates. We here found that AWC disorders the information processing in AFD-AWC-AIY circuit for regulating temperature-evoked posture dynamics. Under slow temperature ramp-up, AWC adjusts AFD response, whereby broadening the temperature range in which animals exhibit fluctuating posture undulation. Under rapid temperature ramp-up, AWC increases inter-individual variability in AIY activity and the fluctuating posture undulation. We propose that a compact nervous system recruits a sensory neuron as a fluctuation inducer for regulating sensory-dependent behavior.

A statistical mechanics approach to cultural evolution of structured behavior in non-human primates: From disorder to tetris-like structures

This paper explores a statistical mechanics approach to cultural evolution of structured behavior in non-human primates. Previous works on cultural evolution have proposed Iterated Learning procedures, in which the behavioral output of one individual becomes the target behavior for the next individual in the chain. Within this line of research, previous work has suggested that even in non-human primates this paradigm shows that cultural transmission can lead to the progressive emergence of tetris-like structures. Our simulations are based on several interrelated statistical mechanics measurements, which quantify the way structures become closer to each other and the tendency to put activated cells together (understood by means of a number of measures and an energy-like function). With these tools, we suggested the hypothesis that the appearance of tetris-like structures might be an indirect consequence of the energy-like minimization. From this, it is plausible to think that the preference of the participants for tetris-like structures is strongly related to some kind of minimization towards simplicity in cognition.

Functional Role of Pulvinar In the Sustained Attention

Sustained attention is important for survival in a challenging environment. Oscillatory activities in the pulvinar have been reported to correlate with sustained attention. However, whether pulvinar can causally establish and maintain sustained attention is elusive. To address this question, in this study, we opto-genetically activated pulvinar neurons during delay period in the five-choice serial reaction time task and measured the behavioral outputs. We found that pulvinar firing rates were significantly increased after optogenetic stimulation. Also, in the behavioral test, the correct rates were remarkably increased with decreased omission rates, but the reaction time and reward retrieval time remained the same. Together, these results deepen our understanding of the functional role of pulvinar in sustained attention.

Investigating Unused Tools for the Animal Behavioral Diversity Toolkit.

Behavioral diversity is a commonly used tool used to quantify the richness and evenness of animal behaviors and assess the effect of variables that may impact an animal's quality of life. The indices used in behavioral diversity research, and the study subjects, have not been formally reviewed. This paper aims to identify which indices are being used in behavioral diversity research, and under which scenarios, and uncover novel indices from other disciplines that could be applied to behavioral diversity. To investigate the techniques and species investigated in behavioral diversity literature, a Web of Science literature search was conducted. Two methods: behavioral richness and the Shannon-Wiener index, were the most frequently used indices, whereas the Behavioral Variability index featured rarely. While a range of species appeared in the behavioral literature, mammals were the most frequently studied Class, whereas amphibians did not feature in any papers. There are several diversity indices which did not feature in behavioral diversity including Simpson's index, and Chao. Such indices could be used to better understand animal behavioral study outputs or be used to estimate the number of 'unobserved' behaviors that an animal may express. Future studies could therefore extend beyond the Shannon-Wiener and richness indices.

Post-embryonic remodeling of the C. elegans motor circuit

During development, animals can maintain behavioral output even as underlying circuitry structurally remodels. After hatching, C.elegans undergoes substantial motor neuron expansion and synapse rewiring while the animal continuously moves with an undulatory pattern. To understand how the circuit transitions from its juvenile to mature configuration without interrupting functional output, we reconstructed the C.elegans motor circuit by electron microscopy across larval development. We observed the following: First, embryonic motor neurons transiently interact with the developing post-embryonic motor neurons prior to remodeling of their juvenile wiring. Second, post-embryonic neurons initiate synapse development with their future partners as their neurites navigate through the juvenile nerve cords. Third, embryonic and post-embryonic neurons sequentially build structural machinery needed for the adult circuit before the embryonic neurons relinquish their roles to post-embryonic neurons. Fourth, this transition is repeated region by region along the body in an anterior-to-posterior sequence, following the birth order of neurons. Through this orchestrated and programmed rewiring, the motor circuit gradually transforms from asymmetric to symmetric wiring. These maturation strategies support the continuous maintenance of motor patterns as the juvenile circuit develops into the adult configuration.

A Review of the Self-Powered Wiegand Sensor and Its Applications

Self-powered magnetic sensors are fundamental for the development of Industry 4.0, the Internet of things (IoT), wireless sensor networks, unmanned vehicles, smart cities, and sustainability. This review aimed to elucidate the working principles, materials, manufacture, output properties, and perspectives of Wiegand sensors. A Wiegand sensor is composed of a magnetic sensing wire, which is called a Wiegand wire, and a pick-up coil for the output of an electrical signal and energy. The Wiegand sensor requires an external magnetic field of about 70 Gauss to induce Wiegand wire flux changes, which, in turn, generate an output pulse in the pick-up coil. Output energy of more than 3000 nJ per single pulse (open circuit) can be harvested. The output pulse is derived from the large Barkhausen effect. Therefore, the behavior of the sensor output is independent of the triggering and sensing frequencies. The objective of this review article was to comprehensively highlight research endeavors devoted to Wiegand sensors. Furthermore, application scenarios of current research results are highlighted to find potential gaps in the literature and future contributions. Perspectives and research opportunities of Wiegand sensors are proposed.

Cannabidiol, but Not Δ9-Tetrahydrocannabinol, Has Strain- and Genotype-Specific Effects in Models of Psychosis.

Introduction: Cannabis use has been associated with an increased incidence of psychiatric disorders, yet the underlying neurobiological processes mediating these associations are poorly understood. Whereas exposure to Δ9-tetrahydrocannabinol (THC) has been associated with the development or exacerbation of psychosis, treatment with cannabidiol (CBD) has been associated with amelioration of psychosis. In this study, we demonstrate a complex effect of CBD in mouse models of psychosis, based on factors, including dose, strain, and genotype. Methods: Adult GluN1 knockdown (GluN1KD) and dopamine transporter knockout (DATKO) mice (almost equally balanced for male/female) were acutely treated with vehicle, THC (4 mg/kg), CBD (60, 120 mg/kg), or THC:CBD (1:15, 4:60 mg/kg) and tested in behavioral assays. Results: GluN1KD and DATKO mice displayed hyperactivity, impaired habituation, and sensorimotor gating, along with increased stereotypy and vertical activity. THC, alone and in combination with CBD, produced a robust "dampening" effect on the exploratory behavior regardless of strain or genotype. CBD exhibited a more complex profile. At 60 mg/kg, CBD had minimal effects on horizontal activity, but the effects varied in terms of directionality (increase vs. decrease) in other parameters; effects on stereotypic behaviors differ by genotype, while effects on vertical exploration differ by strain×genotype. CBD at 120 mg/kg had a "dampening" effect on exploration overall, except in GluN1KD mice, where no effect was observed. In terms of sensorimotor gating, both THC and CBD had minimal effects, except for 120 mg/kg CBD, which exacerbated the acoustic startle response. Conclusions: Here, we present a study that highlights the complex mechanism of phytocannabinoids, particularly CBD, in models of psychosis-like behavior. These data require careful interpretation, as agonism of the cannabinoid receptor 1 (CB1) resulting in a decrease in locomotion can be misinterpreted as "antipsychotic-like" activity in murine behavioral outputs of psychosis. Importantly, the THC-mediated decrease in hyperexploratory behavior observed in our models (alone or in combination) was not specific to the genetic mutants, but rather was observed regardless of strain or genotype. Furthermore, CBD treatment, when comparing mutants with their wild-type littermate controls, showed little to no "antipsychotic-like" activity in our models. Therefore, it is not only important to consider dose when designing/interpreting therapeutically driven phytocannabinoid studies, but also effects of strain or genetic vulnerability respective to the general population.

Machine Learning Based Surrogate Models for the Thermal Behavior of Multi-Plate Clutches

Multi-plate clutches play safety-critical roles in many applications. For this reason, correct functioning and safe operation are essential. Spontaneous damages are particularly critical because the failure of the clutch can lead to a failure of the system. Such damage mainly occurs due to very high loads and ultimately very high temperatures. Finite Element Analysis (FEA) enables simulation and prediction of these temperatures, but it is very time-consuming and costly. In order to reduce this computational effort, surrogate models can be created using machine learning (ML) methods, which reproduce the input and output behavior. In this study, various ML methods (polynomial regression, decision tree, support vector regressor, Gaussian process and neural networks) are evaluated with respect to their ability to predict the maximum clutch temperature based on the loads of a slip cycle. The models are examined based on two use cases. In the first use case, the axial force and the speed are varied. In the second use case, the lining thickness is additionally modified. We show that ML approaches fundamentally achieve good results for both use cases. Furthermore, we show that Gaussian process and backpropagation neural network provide the best results in both cases and that the requirement to generate predictions during operation is fulfilled.

Effect on Diesel Engine Performance Parameters Using Hydrogen and Oxygen Produced on Demand

Hydrogen is seen as a future energy carrier since its chemical compounds make up a large part of the Earth’s surface. This study sought to analyze the impact related to the inclusion of hydrogen and oxygen gases produced on demand by an alkaline electrolyzer to the engine added directly through the fuel intake line. For this purpose, performance parameters were monitored, such as liquid fuel consumption and greenhouse gas emissions, and correlated to any effect observed on the engine’s power output and combustion behavior. A 58 kVA nominal power motor-generator was used, coupled with a resistive load bank (20 kW), where two fuel configurations were tested (diesel injection only and a mixture of diesel, hydrogen and oxygen) and compared. A total of 42 tests were performed considering both the admission gases into the fuel intake line and also diesel supply only for baseline. A substantial decrease in fuel consumption was observed (7.59%) when the blend configuration was used despite a decrease in the engine’s work (1.07%). It was also possible to see a common pattern between NO and NO2 emissions for both fuel configurations, while the behavior of the CO2 and CO emissions indicated a higher complete diesel burning fraction when using the gases on demand. Therefore, we can verify that the use of hydrogen and oxygen gases produced on demand in the fuel intake line is a promising alternative to provide a decrease in liquid fuel consumption and an overall improvement in engine combustion.