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Heterostacks formed by combining two-dimensional materials show novel properties which are of great interest for new applications in electronics, photonics and even twistronics, the new emerging field born after the outstanding discoveries on twisted graphene. Here, we report the direct growth of tin nanosheets at the two-dimensional limit via molecular beam epitaxy on chemical vapor deposited graphene on Al2O3(0001). The mutual interaction between the tin nanosheets and graphene is evidenced by structural and chemical investigations. On the one hand, Raman spectroscopy indicates that graphene undergoes compressive strain after the tin growth, while no charge transfer is observed. On the other hand, chemical analysis shows that tin nanosheets interaction with sapphire is mediated by graphene avoiding the tin oxidation occurring in the direct growth on this substrate. Remarkably, optical measurements show that the absorption of tin nanosheets show a graphene-like behavior with a strong absorption in the ultraviolet photon energy range, therein resulting in a different optical response compared to tin nanosheets on bare sapphire. The optical properties of tin nanosheets therefore represent an open and flexible playground for the absorption of light in a broad range of the electromagnetic spectrum and technologically relevant applications for photon harvesting and sensors., Comment: 14 pages, 7 figures

Background: Molecules, bearing an active methylene bridge, are deemed to be one of the most fruitful and remarkable precursors that have been incorporated in the synthetic strategy of an assortment of bioactive compounds. Objective: The reactive methylene derivatives have been endowed with multiple reactions, which target biological and medicinal applications and are resultant from their structural multiplicity and discrete reactivity. Methods: The present report endeavors to synthesize, characterize, and in-vitro evaluate several novel propanoic acid, coumarin, and pyrazole derivatives as antimicrobial and antiproliferative agents. The in-silico molecular docking, physicochemical, pharmacokinetic/ADMET, bioactivity, and drug likeness predictions were conducted for all the synthesized compounds. Results: The highest docking score is -9.9 and -8.3 kcal/mol respectively for compound 9 (azo-coumarin) and 13 (acrylic acid derivative) with the target proteins E. coli topoisomerase II, DNA gyrase subunit B and PI3K p110α domain, respectively. Moreover, this study predicts the synthesized molecules that may inhibit the novel COVID-19, obtained through virtual screenings only, where compounds 9, 13, 14, 17, and 19 came to the limelight with good docking scores i.e more than 8 Kcal/mol. Safety profiling of the most potent compound 9 was utilized against normal cell line and hemolytic effect on RBCs. Conclusion: The in-silico ADMET studies of the synthesized compounds revealed moderate to good drug likeness, high gastro intestinal (GI) absorption, inhibits the Cytochrome CYP2C19 and CYP2C9 and all the derivatives possess non-cancerous nature. The in-vitro screening demonstrated that several of the novel molecules are promising drug candidates. The density function theory (DFT) theoretical calculations were performed to calculate the energy levels of the FMOs and their energy gabs, dipole moment as well as the molecular electrostatic potential. Such parameters along with the physicochemical parameters could be good tool to confirm the biological activity.

The study investigated the cortical activity changes and time production task performance induced by changes in motion speed of a non-immersive 3D virtual stimulus.Twenty-one individuals were participated in the crossover study with the visual-time reproduction task under three-speed conditions: original, slow and fast virtual stimulus. In addition, the electroencephalographic analysis of the theta band power in the dorsolateral prefrontal cortex was done simultaneously with time production task execution.The results demonstrated that in the slow speed condition, there is an increase in the error in the time production task after virtual reality (We propose that the modulations of speed of virtual stimulus may underlie the accumulation of temporal pulses, which could be responsible for changes in the performance of the production task of the time intervals and a substantial increase in right dorsolateral prefrontal cortex activity related to attention and memory, acting in cognitive domains of supraseconds.

Stabilization of silicene and preservation of its structural and electronic properties are essential for its processing and future integration into devices. The stacking of silicene on stanene, creat- ing a Xene-based heterostructure, proves to be a viable new route in this respect. Here we demonstrate the effectiveness of a stanene layer in breaking the strong interaction between silicene and the Ag(111) substrate. The role of stanene as a ‘buffer’ layer is investi- gated by analyzing the optical response of epitaxial silicene through both power-dependent Raman spectroscopy and reflectivity mea- surements in the near infrared (NIR)–ultraviolet (UV) spectral range. Finally, we point out a Xene-induced shift of the silver plasma edge that paves the way for the development of a new approach to engineering the metal plasmonic response.

International audience; Bismuth-Antimony alloys () is the first reported 3D Topological Insulator (TI). Among many TIs reported to the date, it remains the most promising for spintronic applications thanks to its large conductivity, its colossal spin Hall angle, and the possibility to build low current spin-orbit-torque (SOT) magnetoresistive random access memories (MRAM). Nevertheless, the 2D integration of TIs on industrial standards is lacking. In this work, we report the inte

This study investigated whether time-estimation task exposure influences the severity of Attention Deficit Hyperactivity Disorder (ADHD), as well as theta band activity in the dorsolateral prefrontal cortex and ventrolateral prefrontal cortex.Twenty-two patients with ADHD participated in a crossover experiment with a visual time-estimation task under control conditions (without exposure to time estimation tasks) and experimental (thirty days exposure to time-estimation tasks) in association with electroencephalographic analysis of theta band.ADHD patients with thirty days of time-estimation task exposure presented a worse performance of the time-estimation task, as revealed by the measurements of the absolute error and relative error (We propose that the decrease in EEG theta power may indicate an efficient accumulation of temporal pulses, which could be responsible for the improvement in the patient cognitive aspects as demonstrated by the current study. Time-estimation task improves ADHD cognitive symptoms, with a substantial increase in cortical areas activity related to attention and memory, suggesting its use as a tool for cognitive timing function management and non-invasive therapeutic aid in ADHD.

Several studies have demonstrated that stroke subjects present impairment of functions related to decision-making and timing, involving the information processing in the neural circuits of the cerebellum in association with the prefrontal cortex. This review is aimed to identify the gaps, and demonstrate a better understanding of decision-making and timing functions in the patients with stroke. Electronic literature database was searched and the findings of relevant studies were used to explore the mechanisms of decision-making and timing in patients with stroke, as well as the circuit connections in timing mediated by prefrontal cortex and cerebellum. A literature review was conducted with 65 studies that synthesized findings on decision-making and time perception in individuals with stroke. Types of neurobiological modalities in this study included: Relationships among decision-making, time perception, related cognitive aspects (such as discrimination tasks, verbal estimation, bisection tasks, time production and motor reproduction), and motor control. We demonstrate that the timing processes are important for the performance in cognitive tasks and that the cerebellum and prefrontal cortex are involved in decision-making and time perception. In the context, the decision-making is impaired in stroke patients has a great impact on executive functions, and this seems to be important in determining neurobiological aspects relevant to the time interval interpretation.

Integrating self-catalyzed InAs nanowires on Si(111) is an important step toward building vertical gate-all-around transistors. The complementary metal oxide semiconductor (CMOS) compatibility and the nanowire aspect ratio are two crucial parameters to consider. In this work, we optimize the InAs nanowire morphology by changing the growth mode from Vapor–Solid to Vapor–Liquid–Solid in a CMOS compatible process. We study the key role of the Hydrogen surface preparation on nanowire growths and bound it to a change of the chemical potential and adatoms diffusion length on the substrate. We transfer the optimized process to patterned wafers and adapt both the surface preparation and the growth conditions. Once group III and V fluxes are balances, aspect ratio can be improved by increasing the system kinetics. Overall, we propose a method for large scale integration of CMOS compatible InAs nanowire on silicon and highlight the major role of kinetics on the growth mechanism.

This study investigated the bromazepam effects in male subjects during the time estimation performance and EEG alpha asymmetry in electrodes associated with the frontal and motor cortex.This is a double-blind, crossover study with a sample of 32 healthy adults under control (placebo) vs. experimental (bromazepam) during visual time-estimation task in combination with electroencephalographic analysis.The results demonstrated that the bromazepam increased the relative error in the 4 s, 7 s, and 9 s intervals (p = 0.001). In addition, oral bromazepam modulated the EEG alpha asymmetry in cortical areas during the time judgment (p ≤ 0.025).The bromazepam decreases the precision of time estimation judgments and modulates the EEG alpha asymmetry, with greater left hemispheric dominance during time perception. Our findings suggest that bromazepam influences internal clock synchronization via the modulation of GABAergic receptors, strongly relating to attention, conscious perception, and behavioral performance.

This study investigated the differences in frontoparietal EEG gamma coherence between expert meditators (EM) and naïve meditators (NM).This is a cross-sectional study with a sample of twenty-one healthy adults divided under two groups (experts meditators vs. naive-meditators), with analyzing the intra-hemispheric coherence of frontoparietal gamma oscillations by electroencephalography during the study steps: EEG resting-state 1, during the open presence meditation practice, and EEG resting-state 2.The findings demonstrated greater frontoparietal EEG coherence in gamma for experts meditators in the Fp1-P3, F4-P4, F8-P4 electrode pairs during rest 1 and rest 2 (p ≤ 0.0083). In addition, we evidenced differences in the frontoparietal EEG coherence for expert meditators in F4-P4, F8-P4 during the meditation (p ≤ 0.0083).Our results can support evidence that the connectivity of the right frontoparietal network acts as a biomarker of the enhanced Open monitoring meditation training.

The voluntary movement demands integration between cognitive and motor functions. During the initial stages of motor learning until mastery of a new motor task, and during a demanding task that is not automatic, cognitive and motor functions can be perceived as independent from each other. Areas used for actually performing motor tasks are essentially the same used by Motor Imagery (MI). The main objective of this study was to investigate inhibition effects on cognitive functions of motor skills induced by low-frequency (1 Hz) Repetitive Transcranial Magnetic Stimulation (rTMS) at the sensory-motor integration site (Cz). In particular, the goal was to examine absolute alpha and beta power changes on frontal regions during Execution, Action observation, and Motor Imagery of finger movement tasks. Eleven healthy, right-handed volunteers of both sexes (5 males, 6 females; mean age 28 ± 5 years), with no history of psychiatric or neurological disorders, participated in the experiment. The execution task consisted of the subject flexing and extending the index finger. The action observation task involved watching a video of the same movement. The motor imagery task was imagining the flexion and extension of the index finger movement. After performing the tasks randomly, subjects were submitted to 15 min of low-frequency rTMS and performed the tasks again. All tasks were executed simultaneously with EEG signals recording. Our results demonstrated a significant interaction between rTMS and the three tasks in almost all analyzed regions showing that rTMS can affect the frontal region regarding Execution, Action observation, and Motor Imagery tasks.

Temporal structure of cognitive and sensory processing holds the key to understanding complex neural mechanisms involved in higher order brain functions like perception of time. A hypothesis of embodied cognition posits that cognitive processes are deeply rooted in the interactions with the external world (Wilson et al., 2002; Anderson et al., 2012). These interactions of the brain with the external world depend on the accurate representation of the time-dimension in neural circuits (Gupta, 2014). For example, one cannot catch a flying ball unless the timing of the movements matches the speed of the ball. Many real world situations depend on the mapping between the neural and physical representation of time, which is maintained at different hierarchical levels. Hierarchical processing, consistent with multiple time scales, is manifested during goal-driven tasks, such as interval timing, duration judgement, and movement coordination. Contributions to this Research Topic elucidate how key aspects of the time-dimension such as the temporal binding of neural events play important roles in various cognitive processes, which include perception, mental time travel, and speech production. Additionally, the multi-scale representation of such processes from the micro to meso scales—from single neurons to a population of neurons to field potentials and macroscopic scales of EEG - is, discussed.

The storage of temporally precise spike patterns can be realized by a single neuron. A spiking neural network (SNN) model is utilized to demonstrate the ability to precisely recall a spike pattern after presenting a single input. We show by using a simulation study that the temporal properties of input patterns can be transformed into spatial patterns of local dendritic spikes. The localization of time-points of spikes is facilitated by phase-shift of the subthreshold membrane potential oscillations (SMO) in the dendritic branches, which modifies their excitability. In reference to the points in time of the arriving input, the dendritic spikes are triggered in different branches. To store spatially distributed patterns, two unsupervised learning mechanisms are utilized. Either synaptic weights to the branches, spatial representation of the temporal input pattern, are enhanced by spike-timing-dependent plasticity (STDP) or the oscillation power of SMOs in spiking branches is increased by dendritic spikes. For retrieval, spike bursts activate stored spatiotemporal patterns in dendritic branches, which reactivate the original somatic spike patterns. The simulation of the prototypical model demonstrates the principle, how linking time to space enables the storage of temporal features of an input. Plausibility, advantages, and some variations of the proposed model are also discussed.

Methylphenidate produces its effects via actions on cortical areas involved with attention and working memory, which have a direct role in time estimation judgment tasks. In particular, the prefrontal and parietal cortex has been the target of several studies to understand the effect of methylphenidate on executive functions and time interval perception. However, it has not yet been studied whether acute administration of methylphenidate influences performance in time estimation task and the changes in alpha band absolute power in the prefrontal and parietal cortex. The current study investigates the influence of the acute use of methylphenidate in both performance and judgment in the time estimation interpretation through the alpha band absolute power activity in the prefrontal and parietal cortex. This is a double-blind, crossover study with a sample of 32 subjects under control (placebo) and experimental (methylphenidate) conditions with absolute alpha band power analysis during a time estimation task. We observed that methylphenidate does not influence task performance (p > 0.05), but it increases the time interval underestimation by over 7 s (p

AIM OF THE STUDY Previous studies have shown that several cortical regions are involved in temporal tasks in multiple timescales. However, the hemispheric predominance of the dorsolateral prefrontal cortex (DLPFC) during time reproduction after repetitive low-frequency transcranial magnetic stimulation (rTMS) is relatively unexplored. Here, we study the effects of 1 Hz rTMS and sham stimulation applied medially over the superior parietal cortex (SPC) on the DLPFC alpha and beta band asymmetry and on time reproduction. MATERIALS AND METHODS For this purpose, we have combined rTMS with electroencephalography in 20 healthy subjects who performed the time reproduction task in two conditions (sham and 1 Hz). RESULTS The worst performance was observed in sham and 1Hz conditions for longer time intervals (p

Parkinson disease causes several changes in gait, such as postural stability, which consequently induces fall risk factors and loss of quality of life. Alternative forms of treatment through rhythmic and dance stimuli have been used to minimize the Parkinson disease effects, which have been shown to be effective in improving gait and providing social well-being and quality of life in the patient. Aim: This review aims to demonstrate the efficiency of music and dance for gait improvement and symptom alleviation in Parkinson disease. Methodology: Studies that analyzed sound stimuli and dance in gait improvement in Parkinson disease were searched through PubMed, Scopus, Doaj, MEDLINE, and ScienceDirect databases from November 2017 to April 2018 and repeated in September 2018. Results and Discussion: Forty-five studies met the inclusion criteria to synthesize the findings on dance and music performance as a treatment for classical symptoms of Parkinson disease. Five reviews and 40 experimental papers have shown that rhythmic stimulation and dance provide the motor, cognitive, and quality of life benefits for participants with Parkinson disease. Thus, sound stimuli and dance offer satisfactory effects for gait, improving cognitive abilities such as motor control and adjustment and spatial memory. In addition, these new treatment modalities stimulate the elderly population to practice physical exercise, generating well-being and helping self-esteem. Conclusion: Dance and music therapy interventions are noninvasive, simple treatment options, which promote gait and cognition.

Background Parkinson’s disease is described as resulting from dopaminergic cells progressive degeneration, specifically in the substantia nigra pars compacta that influence the voluntary movements control, decision making and time perception. Aim This review had a goal to update the relation between time perception and Parkinson’s Disease. Methodology We used the PRISMA methodology for this investigation built guided for subjects dopaminergic dysfunction in the time judgment, pharmacological models with levodopa and new studies on the time perception in Parkinson’s Disease. We researched on databases Scielo, Pubmed / Medline and ISI Web of Knowledge on August 2017 and repeated in September 2017 and February 2018 using terms and associations relevant for obtaining articles in English about the aspects neurobiology incorporated in time perception. No publication status or restriction of publication date was imposed, but we used as exclusion criteria: dissertations, book reviews, conferences or editorial work. Results/Discussion We have demonstrated that the time cognitive processes are underlying to performance in cognitive tasks and that many are the brain areas and functions involved and the modulators in the time perception performance. Conclusions The influence of dopaminergic on Parkinson’s Disease is an important research tool in Neuroscience while allowing for the search for clarifications regarding behavioral phenotypes of Parkinson’s disease patients and to study the areas of the brain that are involved in the dopaminergic circuit and their integration with the time perception mechanisms.

Perception and motor interaction with physical surroundings can be analyzed by the changes in probability laws governing two possible outcomes of neuronal activity, namely the presence or absence of spikes (binary states). Perception and motor interaction with the physical environment are partly accounted for by a reduction in entropy within the probability distributions of binary states of neurons in distributed neural circuits, given the knowledge about the characteristics of stimuli in physical surroundings. This reduction in the total entropy of multiple pairs of circuits in networks, by an amount equal to the increase of mutual information, occurs as sensory information is processed successively from lower to higher cortical areas or between different areas at the same hierarchical level, but belonging to different networks. The increase in mutual information is partly accounted for by temporal coupling as well as synaptic connections as proposed by Bahmer and Gupta (Front. Neurosci. 2018). We propose that robust increases in mutual information, measuring the association between the characteristics of sensory inputs&rsquo, and neural circuits&rsquo, connectivity patterns, are partly responsible for perception and successful motor interactions with physical surroundings. The increase in mutual information, given the knowledge about environmental sensory stimuli and the type of motor response produced, is responsible for the coupling between action and perception. In addition, the processing of sensory inputs within neural circuits, with no prior knowledge of the occurrence of a sensory stimulus, increases Shannon information. Consequently, the increase in surprise serves to increase the evidence of the sensory model of physical surroundings

Perception and motor interaction with physical surroundings can be analyzed by the changes in probability laws governing two possible outcomes of neuronal activity, namely the presence or absence of spikes (binary states). Perception and motor interaction with physical environment are accounted partly by the reduction in entropy within the probability distributions of binary states of neurons in distributed neural circuits, given the knowledge about the characteristics of stimuli in physical surroundings. This reduction in the total entropy of multiple pairs of circuits in networks, by an amount equal to the increase of mutual information among them, occurs as sensory information is processed successively from lower to higher cortical areas or between different areas at the same hierarchical level but belonging to different networks. The increase in mutual information is partly accounted by temporal coupling as well as synaptic connections as proposed by Bahmer and Gupta [1]. We propose that robust increases in mutual information, measuring the association between the characteristics of sensory inputs and neural circuits connectivity patterns, are partly responsible for perception and successful motor interactions with physical surroundings. It is also argued that perception from a sensory input is the result of networking of many circuits to a common circuit that primarily processes the given sensory input.

Bromazepam emulates the inhibitory effect of the neurotransmitter gamma-aminobutyric acid (GABA) and can lead to impaired visuomotor performance. However, few studies have evaluated its effects on cortical coupling in target shooting activities. The present study aimed to analyze the acute effects of bromazepam administration in a target shooting task and the EEG theta rhythm coherence between frontal, temporal, and motor cortical areas in four shooting preparation periods. Thus, a double blind, crossover study was conducted with 30 subjects under two conditions: bromazepam (6mg) and placebo, with electroencephalographic analysis to simultaneously study the theta rhythm coherence in frontal, temporal, and motor cortex in a target shooting task; and the possible interferences of bromazepam administration. Subjects in the bromazepam group showed lower performance on the task compared to placebo (p=0.001). In addition, our analysis showed decreased coherence between regions in the same hemisphere, increased theta rhythm coherence in interhemispheric regions in frontal, temporal and motor cortex at different intervals in the preparation preceding the shooting (p=0.001). The use of bromazepam may influence task execution, possibly due to neurochemical modulation, during decision making, developing shooting preparation strategies, as well as interfering with the flow of information at the level of attention during task execution. El bromazepam imita el efecto inhibidor del neurotransmisor ácido gamma-aminobutírico (GABA) y puede provocar un deterioro del rendimiento visuomotor. Sin embargo, pocos estudios han evaluado sus efectos sobre el acoplamiento cortical en las actividades de tiro al blanco. El presente estudio tuvo como objetivo analizar los efectos agudos de la administración de bromazepam en una tarea de tiro al blanco y la coherencia del ritmo theta del EEG entre las áreas corticales frontales, temporales y motoras en cuatro períodos de preparación de tiro. Así, se realizó un estudio cruzado y a doble ciego con 30 sujetos en dos condiciones: bromazepam (6 mg) y placebo, con análisis electroencefalográfico para estudiar simultáneamente la coherencia del ritmo theta en la corteza frontal, temporal y motora en una tarea de tiro al blanco; y las posibles interferencias de la administración de bromazepam. Los sujetos del grupo de bromazepam mostraron un menor rendimiento en la tarea en comparación con el placebo (p=0,001). Además, nuestro análisis mostró una disminución de la coherencia entre regiones del mismo hemisferio y un aumento de la coherencia del ritmo theta en regiones interhemisféricas de la corteza frontal, temporal y motora a diferentes intervalos en la preparación que precede al disparo (p=0,001). El uso de bromazepam puede influir en la ejecución de la tarea, posiblemente debido a la modulación neuroquímica, durante la toma de decisiones, el desarrollo de estrategias para preparar el tiro, así como la interferencia en el flujo de información a nivel de la atención durante la ejecución de la tarea. O bromazepam imita o efeito inibidor do neurotransmissor ácido gama-aminobutírico (GABA) e podem levar ao prejuízo do desempenho visuomotor. No entanto, poucos estudos avaliaram seus efeitos no acoplamento cortical em atividades de tiro ao alvo. O presente estudo objetivou analisar os efeitos agudo da administração de bromazepam numa tarefa de tiro ao alvo e a coerência do ritmo teta do EEG entre as áreas da cortical frontal, temporal, e motora em quatro períodos preparatórios de tiro. Desse modo, foi realizado um estudo crossover e duplo cego, com 30 sujeitos sob duas condições: bromazepam (6mg) e placebo, com análise eletroencefalográfica para estudar simultaneamente a coerência do ritmo teta no córtex frontal, temporal e motor, numa tarefa de tiro ao alvo; e as possíveis interferências da administração do bromazepam. Os sujeitos do grupo bromazepam apresentaram um desempenho inferior na tarefa em comparação com o placebo (p=0,001). Além disso, a nossa análise mostrou uma diminuição da coerência entre regiões no mesmo hemisfério, um aumento da coerência do ritmo teta nas regiões interhemisféricas no córtex frontal, temporal e motor em diferentes intervalos na preparação que antecedeu o tiroteio (p=0,001). O uso de bromazepam pode influenciar a execução da tarefa, possivelmente devido à modulação neuroquímica, durante a tomada de decisões, desenvolvendo estratégias de preparação do tiro, além de interferir com o fluxo de informação ao nível da atenção durante a execução da tarefa.

Catching a thrown ball requires a tight coupling between perception and motor control. In this review, we examine multidimensional information processing across various perceptual and motor tasks. We summarize how perception, timing and action can be understood in terms of the coupling of gamma band oscillations, which represent the local activities of brain circuits, to a specific phase of long-range low-frequency oscillations. We propose a temporal window of integration that emerges from cross-frequency coupling that serves to produce optimized action.

Transcranial direct current stimulation (tDCS) has been used as a non-invasive method for enhanced motor and cognitive abilities. However, no previous study has investigated if the tDCS application in unskilled shooters on cortical sites, selected based on the cortical activity of skilled shooters, improves the accuracy and shot grouping. Sixty participants were selected, which included 10 skilled shooters and 50 unskilled shooters. After we identified the right dorsolateral prefrontal cortex (DLPFC) as the area with the highest activity in skilled shooters, we applied anodal tDCS over the right DLPFC in the unskilled shooters under two conditions: sham-tDCS (placebo) and real-tDCS (anodal tDCS). We also analyzed electroencephalography. Our results indicated that anodal tDCS application enhanced the shot accuracy (p = 0.001). Furthermore, the beta power in the EEG recording was higher in the left DLPFC, left and right parietal cortex (p = 0,001) after applying anodal tDCS, while the low-gamma power was higher in the right DLPFC in sham-tDCS (p = 0.001) and right parietal cortex after anodal-tDCS (p = 0.001). Our findings indicate that anodal tDCS can improve accuracy and shot grouping when applied over the unskilled shooters' right DLPFC. Furthermore, beta and low-gamma bands are influenced by anodal tDCS over the right DLPFC, which may be predictive of skill improvement.

Background and objectives Several studies indicate that subjects with Parkinson’s disease present motor impaired, timing and many interventions used to improve their motor behavior, but so far no training protocols that use time-estimation tasks. In this preliminary study, we aimed to report the effects of the time-estimation task training on motor behaviour and the electroencephalographic activity of the dorsolateral prefrontal cortex and motor cortex. Methods We analysed motor-exploration behaviour in 5 Parkinson’s patients using the Unified Parkinson’s Disease Rating Scale, in addition to the alpha band absolute power activity of the electroencephalogram. Results Our results show the motor-exploration behaviour improvement in Parkinson patients after the training (p

The low-frequency repetitive transcranial magnetic stimulation (rTMS) application has been associated with changes in cognitive processes embedded during time perception tasks. Although several studies have investigated the influence of neuromodulation on time perception, the effect of the 1-Hz rTMS application on the superior parietal cortex is not clearly understood. This study analyzes the effect of the low-frequency rTMS on time estimation when applied in the parietal medial longitudinal fissure. For the proposed study, 20 subjects were randomly selected for a crossover study with two conditions (sham and 1 Hz). Our findings reveal that participant underestimate 1-s time interval and overestimate 4-s and 9-s time intervals after 1-Hz rTMS (p ≤ 0.05). We conclude that the 1-Hz rTMS in the parietal medial longitudinal fissure delays short interval and speed up long time intervals. This could be due to the effect of parietal inhibition on the attentional level and working memory functions during time estimation.

We review the role of oscillations in the brain and in the auditory system showing that the ability of humans to distinguish changes in pitch can be explained as a precise analysis of temporal information in auditory signals by neural oscillations. The connections between auditory brain stem chopper neurons construct neural oscillators, which discharge spikes at various constant intervals that are integer multiples of 0.4 ms, contributing to the temporal processing of auditory cochlear output. This is subsequently spatially mapped in the inferior colliculus. Electrophysiological measurements of auditory chopper neurons in different species show oscillations with periods which are integer multiples of 0.4 ms. The constant intervals of 0.4 ms can be attributed to the smallest synaptic delay between interconnected simulated chopper neurons. We also note the patterns of similarities between microcircuits in the brain stem and other parts of the brain (e.g., the pallidum, reticular formation, locus coeruleus, oculomotor nuclei, limbic system, amygdala, hippocampus, basal ganglia and substantia nigra), dedicated to the processing of temporal information. Similarities in microcircuits across the brain reflect the importance of one of the key mechanisms in the information processing in the brain, namely the temporal coupling of different neural events via coincidence detection.

Background Studies at the molecular level aim to integrate genetic and neurobiological data to provide an increasingly detailed understanding of phenotypes related to the ability in time perception. Main Text This study suggests that the polymorphisms genetic SLC6A4 5-HTTLPR, 5HTR2A T102C, DRD2/ANKK1-Taq1A, SLC6A3 3’-UTR VNTR, COMT Val158Met, CLOCK genes and GABRB2 A/C as modification factor at neurochemical levels associated with several neurofunctional aspects, modifying the circadian rhythm and built-in cognitive functions in the timing. We conducted a literature review with 102 studies that met inclusion criteria to synthesize findings on genetic polymorphisms and their influence on the timing. Conclusion The findings suggest an association of genetic polymorphisms on behavioral aspects related in timing. However, order to confirm the paradigm of association in the timing as a function of the molecular level, still need to be addressed future research.

A novel approach for measurement of stable carbon isotopic ratio of atmospheric aerosols was developed by tandem operation of two instruments: a Sunset Organic Carbon-Elemental Carbon (OC-EC) analyzer and an online Carbon Dioxide Stable Isotope Analyzer (LGR, CCIA-36d). Sensitivity, accuracy and measurement uncertainty of the CCIA was comprehensively investigated using the standard reference CO_2 gas with known concentration and isotopic ratio. Drift in CCIA measurement due to varying CO_2 and water vapor concentration was evaluated and a humidity stabilizer was designed and developed to control the water vapor concentration of exhaust gas flow from OC-EC prior to entering the CCIA. A Keeling approach was applied to separate the ratio in the samples from the mixture of PM sample-produced CO_2 and reference gas and we developed a protocol to derive the isotopic composition of the particle samples. A lithium carbonate standard (in powder form) from National Institute of Standards and Technology (NIST) was used to validate measurement of δ^(13)C ratios by CCIA. Offline measurement on ambient aerosol and diesel exhaust aerosols produced comparable results of isotopic ratio with literature values. This study demonstrates the utility of this tandem operation for carbon isotopic measurement of atmospheric particles with better than 1.0 per mille precision as a cost-effective alternative of conventional Isotopic Ratio Mass Spectrometer (IR-MS).

The present study investigated the association of 3′-UTR VNTR and intron 8 VNTR polymorphisms with a time estimation task performance. One hundred and eight men in a Brazilian Northeast population (18–32 years old) participated in the experiment. The 3′-UTR VNTR and intron 8 VNTR polymorphisms were associated alone and combined to absolute error (AE) and relative error (RE) in a time estimation task (target duration: 1 s, 4 s, 7 s and 9 s). We found an association of the behavioral variable with intron 8 VNTR for the time intervals of 1 s and 9 s (p

The development of lung tumors after transplacental N-ethyl-N-nitrosourea (ENU) exposure has been demonstrated in Swiss and Balb/c mice F1 mice. We also suggest the molecular changes that could be affecting the susceptibility to chemical carcinogens during tumor development in the fetus. In this study, ENU administered on the 17th day of gestation resulted in the formation of lung tumors in Balb/c F1 mice, while only lymphocytic infiltration was observed in Swiss F1 mice, at the end of three months. Molecular changes were observed in both strains, but the degree of alteration in some genes was greater in Balb/c F1 mice than in Swiss F1 mice. Administration of 2% inositol hexaphosphate (IP6) to F1 mice attenuated proliferation, inflammation and upregulated the apoptotic machinery, in terms of the expression of cyclin D1, NF-κβ p50, COX-2, mut p53, Bax, Bcl-2, and Bcl-XL including caspase enzyme activities and DNA damage. These could be important pathways involved in lung tumor development in offspring of the carcinogen-predisposed mothers; IP6 attenuated lymphocytic infiltration and tumor development by modulating these events. Analysis of the molecular changes and the chemopreventive potential of IP6 during ENU-induced transplacental lung tumorigenesis suggests that the susceptibility to the induction of lung tumors in Balb/c F1 mice could possibly be due to greater over-expression in Balb/c F1 mice than Swiss F1 mice, of genes involved in proliferation and inflammation in transplacental lung tumor development.

International audience; Anisotropic carbonyl iron-PolyDiMethylSiloxane (PDMS) composites were developed and implemented in microfluidic devices to serve as magnetic flux concentrators. These original materials provide technological solutions for heterogeneous integration with PDMS. Besides microfabrication advantages, they offer interesting modular magnetic properties. Applying an external magnetic field during the PDMS reticulation leads to the formation of 1D-agglomerates of magnetic particles, organized in the non-magnetic polymer matrix. This induces an increase of susceptibility as compared to composites with randomly dispersed particles. In this report, we explored the gain in reachable magnetophoretic forces in operating microfluidic devices, from the study of magnetic micro-beads motion injected in the microchannel. We show that even at relatively large distances from the magnetically-functionalized channel wall, the anisotropic composite leads to a factor two increase in the magnetophoretic force. Finally, further investigations based on finite element description suggest that the measured benefit of anisotropic composite polymers does not only rely on the global susceptibility increase but also on the local magnetic field gradients originating from the microstructure.

Dopaminergic system plays a key role in perception, which is an important executive function of the brain. Modulation in dopaminergic system forms an important biochemical underpinning of neural mechanisms of time perception in a very wide range, from milliseconds to seconds to longer daily rhythms. Distinct types of temporal experience are poorly understood, and the relationship between processing of different intervals by the brain has received little attention. A comprehensive understanding of interval timing functions should be sought within a wider context of temporal processing, involving genetic aspects, pharmacological models, cognitive aspects, motor control and the neurological diseases with impaired dopaminergic system. Particularly, an unexplored question is whether the role of dopamine in interval timing can be integrated with the role of dopamine in non-interval timing temporal components. In this review, we explore a wider perspective of dopaminergic system, involving genetic polymorphisms, pharmacological models, executive functions and neurological diseases on the time perception. We conclude that the dopaminergic system has great participation in impact on time perception and neurobiological basis of the executive functions and neurological diseases.

Spatial working memory has been extensively investigated with different tasks, treatments, and analysis tools. Several studies suggest that low frequency of the repetitive transcranial magnetic stimulation (rTMS) applied to the parietal cortex may influence spatial working memory (SWM). However, it is not yet known if after low-frequency rTMS applied to the superior parietal cortex, according to Pz electroencephalography (EEG) electrode, would change the orientation interpretation about the vertical and horizontal axes coordinates in an SWM task. The current study aims at filling this gap and obtains a better understanding of the low-frequency rTMS effect in SWM. In this crossover study, we select 20 healthy subjects in two conditions (control and 1-Hz rTMS). The subjects performed an SWM task with two random coordinates. Our results presented that low-frequency rTMS applied over the superior parietal cortex may influence the SWM to lead to a larger distance of axes interception point (p

In the present study, we showed the correlation of EZH2, SUV39H1 or G9a expression and histone modifications with the urethane induced mouse lung tumorigenesis in the presence or absence of antitumor agent, inositol hexaphosphate (IP6). Tumorigenesis and the molecular events involved therein were studied at 1, 4, 12 or 36 weeks after the exposure. There were no tumors at 1 or 4 weeks but tumors started appearing at 12 weeks and grew further till 36 weeks after urethane exposure. Among the molecular events, upregulation of EZH2 and SUV39H1 expressions appeared to be time dependent, but G9a expression was altered significantly only at later stages of 12 or 36 weeks. Alteration in miR-138 expression supports the upregulation of its target, EZH2. H3K9me2, H3K27me3 or H4K20me3 was found to be altered at 12 or 36 weeks. However, ChIP analysis of p16 and MLH1 promoters showed their binding with H3K9me2 and H3K27me3 which was maximum at 36 weeks. Thus, histone modification and their interactions with gene promoter resulted in the reduced expression of p16 and MLH1. IP6 prevented the incidence and the size of urethane induced lung tumors. IP6 also prevented the urethane induced alterations in EZH2, SUV39H1, G9a expressions and histone modifications. Our results suggest that the alterations in the histone modification pathways involving EZH2 and SUV39H1 expressions are among the early events in urethane induced mouse lung tumorigenesis and could be exploited for cancer control.

Air pollution becomes severe when air contains small particles, toxic gases, dust and smoke emitted from numerous sources such as vehicles, industries, fires or fumes in harmful amount. Aerosols of highly reflective in nature increases albedo of the earth and thereby cools the surface and thus effectively offsets greenhouse gases warming by about 25-50%; whereas, absorbing type of aerosols absorbs solar radiation hence increases the surface temperature. Absorbing type aerosols are largely present in the urban environment due to presence of relatively larger number of vehicular fleet and subsequent more fossil fuel combustion than in rural area. Excessive inhalation of particulate matter is detrimental to human health as it can lead to asthma, lung cancer and cardiovascular diseases. Thus, it becomes essential to monitor aerosols accurately using affordable device having widespread presence and potential to address the related problematic issues. One of the important parameters in aerosol measurement is aerosol optical depth (AOD). Several instruments and techniques are used to measure AOD such as with satellite and ground based sun-photometry, ground and airborne radiometers and LIDARs which are generally costly and non-portable. Hence, an effort has been made to develop an affordable sun photometer using photo-detectors and light filters which will track the sun automatically and retrieve AOD of that location. Device measurement thus built has been correlated with standard instrument measurement like Microtops Sunphotometer

An extensive filter-based ambient aerosol measurement was carried out at a region that is mostly affected by fog almost every winter. A few fogwater samples were also collected during the study period. Water soluble organic matter (WSOM) was extracted in the aqueous media. The filter extracts and fogwater were analyzed for their chemical constituents using a High Resolution-Time of Flight-Aerosol Mass Spectrometer (HR-ToF-AMS). Data from the HR-ToF-AMS were used in positive matrix factorization (PMF) for the source apportionment to understand the sources of WSOM. Three major sources were identified, namely water soluble biomass burning organic aerosol (WS-BBOA), water soluble oxygenated organic aerosol (WS-OOA), and water soluble primary aerosol (WS-PA). The contributions of WS-BBOA and WS-OOA to WSOM were lower during foggy episodes than during clear (nonfoggy) episodes. The wet scavenging and removal of the aerosols from these sources were the prime causes of their lower contributions. The contribution of WS-PA to WSOM was higher during foggy episodes than during nonfoggy episodes. The higher contribution of this source is attributed to the accumulation of aerosol generated from this source, due to poor dispersion and the calm conditions prevalent during foggy episodes. Surprisingly, the contribution of WS-PA to WSOM was highest among the three sources during both foggy and nonfoggy episodes.

The aim of this study conducted at Kanpur (26.51°N, 80.23°E), India, was to quantify chemical properties of dust and the intensity of mixing, due to its interaction with various emissions from anthropogenic activities, during its long range transport. Aerosol mass was collected at Indian Institute of Technology, Kanpur (IIT-K) located in the Indo-Gangetic Plain from April–July 2011, a period marked by intense dust storms and onset of monsoon. The sampling days were classified as Dust, Polluted Dust1 (PD1), Polluted Dust2 (PD2) and Continental days. PM10 (coarse mode) and PM2.5 (fine mode) collected on filter substrates were analysed for chemical composition. Elemental concentrations were measured using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The results show that crustal elements like Ca, Fe, K, Na and Mg were dominant in coarse mode during dusty days, whereas, elements of anthropogenic origin like Cu, Ni, Se and V were mostly concentrated in fine mode during PD1 as well as PD2. Very low elemental concentrations were found during continental days. SO4 2– , Cl – and NO3 – were found to be high during PD1 and PD2 days. Very good correlations of NH4 + with Cl – and SO4 2– ions in PD1 days indicate their common sources of origin and formation of ammonium chloride and ammonium sulphate. Water Soluble Inorganic Carbon (WSIC) was found during all dust days, Water Soluble Organic Carbon (WSOC) was found to be highest during PD1 and PD2 days.

A number of thiazolidin-4-one and thiazinan-4-one derivatives were prepared by three component condensation in one pot reaction method. These compounds were evaluated for anti-hyperglycemic activity by in vitro and in vivo assay systems. The compounds with thiazolidin-4-one and thiazinan-4-one moieties exhibited significant anti-hyperglycemic activity. A few compounds (3a, 3b, 4a and 4b) have exhibited both anti-hyperglycemic and anti-dyslipidemic activities. Among them the thiazinan-4-one derivative 4a showed maximal (45%) improvement in oral glucose tolerance test in db/db mice at 30 mg/kg oral dose.