Gating Function Research Articles

Gradual wiring of olfactory input to amygdala feedback circuits

The amygdala facilitates odor driven behavioral responses by enhancing the saliency of olfactory signals. Before this processing, olfactory input is refined through the feedback provided by amygdala corticofugal projection (ACPs). Although the saliency of odor signals is subject to developmental changes, the stage at which this cortical feedback first occurs is not known. Using optogenetically-assisted intracellular recordings of the mouse cortical amygdala, we identified changes in the electrophysiological properties of ACPs at different developmental stages. These were consistent with a decrease in neuronal excitability and an increase in the amount of incoming accessory olfactory bulb (AOB) inputs, as confirmed by estimates of release probability, quantal size and contact number at the AOB-to-ACP synapse. Moreover, the proportion of ACPs activated in response to odors was dependent on the stage of development as revealed by c-Fos expression analysis. These results update standard accounts of how the amygdala processes social signals by emphasizing the occurrence of critical periods in the development of its sensory gating functions.

Fault Protection Enabled Gate Drive Circuit for 3-Phase Inverter

Asynchronous motors used in applications like electric vehicles require protection against all possible fault conditions like short circuit, over voltage, over current etc., for their reliable operation. 3-phase inverter is used as power modulator for induction motor. In this paper a novel fault protection scheme is implemented for inverter used in modulating voltage and frequency of power supply driving 3-phase Induction Motor. Function of gate drive circuits used in power electronics converters is to provide isolation for gate signals and shift the voltage level of gate pulses to the required level to enable turn on and turn off the switches as desired. Gate signals are generated using Texas instrument F28069M board. Level shifting is achieved by buffer ICs and fault protection is provided by enabling shut down pin in the DSP on occurrence of fault. Hardware results show that modulation index of gate signals is set to zero under fault conditions and ensure total safety of Inverter driver circuit and power circuit used in the Inverter.

A tetrabenzophenazine low voltage single molecule XOR quantum Hamiltonian logic gate

A tetrabenzo[a,c,j.h]phenazine molecule is functionning like a “2 input – 1 output” XOR Boolean logic gate using the quantum level repulsion effect of the Quantum Hamiltonian Computing approach. The logical inputs are performed using one aluminum atom per input. The logical output is measured by the dI/dV tunnelling spectrum at +1.1 V low bias voltage. On an Au(1 1 1) surface, each Al atom is manipulated in and out of the molecule by scanning tunnelling microscope molecular manipulations. This single molecule XOR gate functions without the need of cascading OR, AND and NAND gates inside its molecular structure.

Modelling for triple gate spin‐FET and design of triple gate spin‐FET‐based binary adder

In this study, an InAs channel-based triple gate spin-field effect transistor (FET) model is proposed. The proposed triple-gate spin-FET offers a high density of integration, consumes low power and offers very high switching speed. By incorporating the suitable parameters like channel length, spin diffusion length, channel resistance and junction polarisation, the modelled triple gate spin-FET is then used to implement 3-input XOR, 3-input XNOR and majority gate functions. The designs of 3-input XOR and majority gates were achieved keeping in view that the sum operation of a 1-bit full adder is obtained through XOR gate and the carry operation of 1-bit full adder is obtained through majority gate. Therefore, for designing a 1-bit full adder, only two spin-FETs will be required which signifies the compact nature of the design. In addition, a 2-bit ripple adder is designed with cascading two 1-bit full-adders. Finally, a comparative analysis of the proposed gates and 1-bit full adder with the reported work and conventional CMOS design was carried out in terms of employed number of devices, power consumption and speed. The analysis shows that proposed gates/adder offer better performance than the reported work and conventional CMOS designs.

Design of on-chip optical logic gates in 2D silicon photonic crystal slab

We have demonstrated the design of two types of on-chip optical logic gates in 2D silicon PC slab, which can support AND and XOR logic gate functions at different input frequencies. Different shapes of the center directional emitting cavity and different input/output directions can lead to different logic operations without nonlinearity or magnetism. More complicated logic networks can be built based on these integrated basic logic gates, which may lead us to construct on-chip large-scale logic circuits.

Ca2+/Calmodulin Binding to STIM1 Hydrophobic Residues Facilitates Slow Ca2+-Dependent Inactivation of the Orai1 Channel.

Store-operated Ca2+ entry (SOCE) through plasma membrane Ca2+ channel Orai1 is essential for many cellular processes. SOCE, activated by ER Ca2+ store-depletion, relies on the gating function of STIM1 Orai1-activating region SOAR of the ER-anchored Ca2+-sensing protein STIM1. Electrophysiologically, SOCE is characterized as Ca2+ release-activated Ca2+ current (ICRAC). A major regulatory mechanism that prevents deleterious Ca2+ overload is the slow Ca2+-dependent inactivation (SCDI) of ICRAC. Several studies have suggested a role of Ca2+/calmodulin (Ca2+/CaM) in triggering SCDI. However, a direct contribution of STIM1 in regulating Ca2+/CaM-mediated SCDI of ICRAC is as yet unclear. The Ca2+/CaM binding to STIM1 was tested by pulling down recombinant GFP-tagged human STIM1 C-terminal fragments on CaM sepharose beads. STIM1 was knocked out by CRISPR/Cas9 technique in HEK293 cells stably overexpressing human Orai1. Store-operated Ca2+ influx was measured using Fluorometric Imaging Plate Reader and whole-cell patch clamp in cells transfected with STIM1 CaM binding mutants. The involvement of Ca2+/CaM in SCDI was investigated by including recombinant human CaM in patch pipette in electrophysiology. Here we identified residues Leu374/Val375 (H1) and Leu390/Phe391 (H2) within SOAR that serve as hydrophobic anchor sites for Ca2+/CaM binding. The bifunctional H2 site is critical for both Orai1 activation and Ca2+/CaM binding. Single residue mutations of Phe391 to less hydrophobic residues significantly diminished SOCE and ICRAC, independent of Ca2+/CaM. Hence, the role of H2 residues in Ca2+/CaM-mediated SCDI cannot be precisely evaluated. In contrast, the H1 site controls exclusively Ca2+/CaM binding and subsequently SCDI, but not Orai1 activation. V375A but not V375W substitution eliminated SCDI of ICRAC caused by Ca2+/CaM, proving a direct role of STIM1 in coordinating SCDI. Taken together, we propose a mechanistic model, wherein binding of Ca2+/CaM to STIM1 hydrophobic anchor residues, H1 and H2, triggers SCDI by disrupting the functional interaction between STIM1 and Orai1. Our findings reveal how STIM1, Orai1, and Ca2+/CaM are functionally coordinated to control ICRAC.

Fan-out enabled spin wave majority gate

By its very nature, Spin Wave (SW) interference provides intrinsic support for Majority logic function evaluation. Due to this and the fact that the 3-input Majority (MAJ3) gate and the inverter constitute a universal Boolean logic gate set, different MAJ3 gate implementations have been proposed. However, they cannot be directly utilized for the construction of larger SW logic circuits as they lack a key cascading mechanism, i.e., fanout capability. In this paper, we introduce a novel ladder-shaped SW MAJ3 gate design able to provide a maximum fanout of 2 (FO2). The proper gate functionality is validated by means of micromagnetic simulations, which also demonstrate that the amplitude mismatch between the two outputs is negligible, proving that an FO2 is properly achieved. Additionally, we evaluate the gate area and compare it with SW state-of-the-art and 15 nm CMOS counterparts working under the same conditions. Our results indicate that the proposed structure requires a 12× less area than the 15 nm CMOS MAJ3 gate and that at the gate level, the fanout capability results in 16% area savings, when compared to the state-of-the-art SW majority gate counterparts.

Analysis on DC and RF/Analog Performance in Multifin-FinFET for Wide Variation in Work Function of Metal Gate

It is well established that increase in number of fins improves the RF/Analog performances of FinFET. In this paper, the effect of work function (ɸM) of metal gate on transfer characteristics, on current (Ion), off current (Ioff), threshold voltage (VT), and subthreshold swing (SS) are reported in Multifin-FinFET. It is seen that both the current ratio (Ion/Ioff) and SS improves as ɸM changes from 4.4 to 4.7 eV. Impact of ɸM on RF/Analog parameters like transconductance (gm), output conductance (gd), intrinsic gain (gm/gd), gate capacitance (Cgg), and cut-off frequency (ft) are investigated for Multifin-FinFET. Analysis reveals that intrinsic gain and cut off frequency improves with increase in ɸM of metal gate.

Experimental and Theoretical Studies on a Simple S-S-Bridged Dimeric Schiff Base: Selective Chromo-Fluorogenic Chemosensor for Nanomolar Detection of Fe2+ & Al3+ Ions and Its Varied Applications.

A simple S–S (disulfide)-bridged dimeric Schiff base probe, L, has been designed, synthesized, and successfully characterized for the specific recognition of Al3+ and Fe2+ ions as fluorometric and colorimetric “turn-on” responses in a dimethylformamide (DMF)-H2O solvent mixture, respectively. The probe L and each metal ion bind through a 1:1 complex stoichiometry, and the plausible sensing mechanism is proposed based on the inhibition of the photoinduced electron transfer process (PET). The reversible chemosensor L showed high sensitivity toward Al3+ and Fe2+ ions, which was analyzed by fluorescence and UV–vis spectroscopy techniques up to nanomolar detection limits, 38.26 × 10–9 and 17.54 × 10–9 M, respectively. These experimental details were advocated by density functional theory (DFT) calculations. The practical utility of the chemosensor L was further demonstrated in electrochemical sensing, in vitro antimicrobial activity, molecular logic gate function, and quantification of the trace amount of Al3+ and Fe2+ ions in real water samples.

Voltage-Energized Calcium-Sensitive ATP Production by Mitochondria

The regulation of ATP production by mitochondria, crucial for multicellular life, is poorly understood. Here, we investigate the molecular controls of this process in the heart and provide a framework for its Ca2+-dependent regulation. We find that the entry of Ca2+ into the matrix through the mitochondrial calcium uniporter (MCU) in the heart has neither an apparent cytosolic Ca2+ threshold nor a gating function, and guides ATP production by its influence on the inner mitochondrial membrane (IMM) potential, ΔΨm. This regulation occurs through matrix Ca2+-dependent modulation of pyruvate and glutamate dehydrogenase activity and not through any effect of Ca2+ on ATP synthase or on electron transport chain complexes II, III or IV. Examining the ΔΨm dependence of ATP production over the range of −60 mV to −170 mV in detail reveals that cardiac ATP synthase has a voltage dependence that distinguishes it fundamentally from the previous standard, the bacterial ATP synthase. Cardiac ATP synthase operates with a different ΔΨm threshold for ATP production than bacterial ATP synthase and reveals a concave-upward shape without saturation. Skeletal muscle MCU Ca2+ flux, while also having no apparent cytosolic Ca2+ threshold, is substantially different from the cardiac MCU, yet the ATP synthase voltage dependence in skeletal muscle is identical to that in the heart. These results suggest that, while the conduction of cytosolic Ca2+ signals through the MCU appears to be tissue dependent, as shown by earlier work1, the control of ATP synthase by ΔΨm appears to be broadly consistent among tissues but is clearly different from that in bacteria. Here the authors provide a regulatory framework for the cardiac mitochondrial ATP synthase, which is shown to be dependent on cellular activity; levels of Ca2+, ADP and NADH; and the potential of the inner mitochondrial membrane.

Effects of Cation Binding to the Intracellular Vestibule of TMEM16 Ion Transport Pathways

TMEM16A and TMEM16F are prototype molecules for the two functional categories of TMEM16 family members, respectively, Ca2+-activated chloride channels and phospholipid scramblases. Upon binding of sub-µM to low µM intracellular Ca2+, TMEM16A conducts anionic currents while TMEM16F is permeable to both cations and anions. In this study, we found another divalent cation, Co2+, while unable to induce current in TMEM16A, inhibits the Ca2+-induced current via competing with Ca2+ for the high-affinity (sub-µM to low µM) channel activation sites. In addition, Co2+ also potentiates the TMEM16A current induced by Ca2+. All alkaline earth divalent cations, including Ca2+ itself, can generate this current potentiation with low affinities—at least hundreds of µM to mM concentrations are required for observing the effect. On the other hand, divalent cations at mM concentrations generate very little potentiation in TMEM16F, likely because the changes in local anion and cation concentrations caused by divalent cation bindings cancel out each other. Nonetheless, divalent cations change the cation/anion selectivity for the TMEM16F current conduction. Manipulating membrane phospholipids alters this low-affinity effect of divalent cations. Recent studies have shown that membrane phospholipids participate in various gating and permeation functions of TMEM16 molecules. Our results suggest that intracellular divalent cations bind to membrane phospholipids with a low affinity to alter the electrostatic potential near or in the ion-transport pathways of TMEM16 molecules. Monovalent cations and polyamine molecules also exert similar effects, although with different apparent affinities. The physiological significance of the TMEM16 current modulation by altering membrane surface potential will be discussed.

A Contextual Bidirectional Enhancement Method for Remote Sensing Image Object Detection

In remote sensing images, the backgrounds of objects include crucial contextual information that may contribute to distinguishing objects. However, there are at least two issues that should be addressed: not all the backgrounds are beneficial, and object information may be suppressed by backgrounds. To address these problems, in this article, we propose the contextual bidirectional enhancement (CBD-E) method to simultaneously remove unexpected background information and enhance objects’ features. CBD-E integrates the features of different background regions sequentially in two directions. On the one hand, a gate function is used to filter out unexpected information in the background and thus improve the recall of detection. On the other hand, a spatial-group-based visual attention mechanism is adopted to enhance the features of objects to reduce the false alarm. The gate function provides an approach to selecting meaningful information in the background, while the spatial-group- based visual attention mechanism enhances the information control ability of the gate function. In the experiments, we have validated the effectiveness of both the gate function and the visual attention mechanism and further demonstrated that the proposed contextual fusion strategy performs well on two published data sets.

Chapter 4 - Amygdala physiology in pain

The amygdala has emerged as an important brain area for the emotional-affective dimension of pain and pain modulation. The amygdala receives nociceptive information through direct and indirect routes. These excitatory inputs converge on the amygdala output region (central nucleus) and can be modulated by inhibitory elements that are the target of (prefrontal) cortical modulation. For example, inhibitory neurons in the intercalated cell mass in the amygdala project to the central nucleus to serve gating functions, and so do inhibitory (PKCdelta) interneurons within the central nucleus. In pain conditions, synaptic plasticity develops in output neurons because of an excitation-inhibition imbalance and drives pain-like behaviors and pain persistence. Mechanisms of pain related neuroplasticity in the amygdala include classical transmitters, neuropeptides, biogenic amines, and various signaling pathways. An emerging concept is that differences in amygdala activity are associated with phenotypic differences in pain vulnerability and resilience and may be predetermining factors of the complexity and persistence of pain.

Biased Mixtures of Experts: Enabling Computer Vision Inference Under Data Transfer Limitations

We propose a novel mixture-of-experts class to optimize computer vision models in accordance with data transfer limitations at test time. Our approach postulates that the minimum acceptable amount of data allowing for highly-accurate results can vary for different input space partitions. Therefore, we consider mixtures where experts require different amounts of data, and train a sparse gating function to divide the input space for each expert. By appropriate hyperparameter selection, our approach is able to bias mixtures of experts towards selecting specific experts over others. In this way, we show that the data transfer optimization between visual sensing and processing can be solved as a convex optimization problem.To demonstrate the relation between data availability and performance, we evaluate biased mixtures on a range of mainstream computer vision problems, namely: (i) single shot detection, (ii) image super resolution, and (iii) realtime video action classification. For all cases, and when experts constitute modified baselines to meet different limits on allowed data utility, biased mixtures significantly outperform previous work optimized to meet the same constraints on available data.

Applying Interval Fuzzy Petri Net to Failure Analysis

In this article, the authors propose a new approach for modelling and failure analysis by combining the graphical representation provided by Petri nets and fuzzy logic. The graphical method is used for describing the relationship between conditions and events. The use of Petri nets in failure analysis enables replacing logic gate functions in fault trees. The Fuzzy logic technique allows natural language descriptions of process entities as well as an if-then rule-based definition of production. In addition, this study devises an alternative, a trapezoidal graph method in order to account for failure scenarios. Examples validating this novel method in dealing with failure analysis are also provided.

Analysis of treatment process time for real-time-image gated-spot-scanning proton-beam therapy (RGPT) system.

We developed a synchrotron‐based real‐time‐image gated‐spot‐scanning proton‐beam therapy (RGPT) system and utilized it to clinically operate on moving tumors in the liver, pancreas, lung, and prostate. When the spot‐scanning technique is linked to gating, the beam delivery time with gating can increase, compared to that without gating. We aim to clarify whether the total treatment process can be performed within approximately 30 min (the general time per session in several proton therapy facilities), even for gated‐spot‐scanning proton‐beam delivery with implanted fiducial markers. Data from 152 patients, corresponding to 201 treatment plans and 3577 sessions executed from October 2016 to June 2018, were included in this study. To estimate the treatment process time, we utilized data from proton beam delivery logs during the treatment for each patient. We retrieved data, such as the disease site, total target volume, field size at the isocenter, and the number of layers and spots for each field, from the treatment plans. We quantitatively analyzed the treatment process, which includes the patient load (or setup), bone matching, marker matching, beam delivery, patient unload, and equipment setup, using the data obtained from the log data. Among all the cases, 90 patients used the RGPT system (liver: n = 34; pancreas: n = 5; lung: n = 4; and prostate: n = 47). The mean and standard deviation (SD) of the total treatment process time for the RGPT system was 30.3 ± 7.4 min, while it was 25.9 ± 7.5 min for those without gating treatment, excluding craniospinal irradiation (CSI; head and neck: n = 16, pediatric: n = 31, others: n = 15); for CSI (n = 11) with two or three isocenters, the process time was 59.9 ± 13.9 min. Our results demonstrate that spot‐scanning proton therapy with a gating function can be achieved in approximately 30‐min time slots.

Somatosensory Processing in Gilles de la Tourette Syndrome

Abstract. In Tourette syndrome, premonitory urges preceding tics play a prominent role, e. g., as an urge to perform a certain action, but also as a cold or warm feeling, the feeling of a mounting tension in the muscles involved in tics or other unpleasant perceptions. The execution of tics results in a temporary reduction of these feelings. Additionally, there is a hypersensitivity to external stimuli and a high level of distractibility. In corroboration of these findings, adolescent Tourette patients show a thinning of the primary somatosensory cortex and secondary somatosensory areas. Also, reduced prepulse inhibition and reductions of short afferent inhibition provide further evidence for deficient inhibitory and gating functions in Tourette patients.

P.485 Imaging brain microglia activation following the peripheral immune challenge Interferon-alpha: A translocation protein study in healthy humans

Matching pedestrians across disjoint camera views, known as person re-identification (re-id), is a challenging problem that is of importance to visual recognition and surveillance. Most existing methods exploit local regions with spatial manipulation to perform matching in local correspondences. However, they essentially extract fixed representations from pre-divided regions for each image and then perform matching based on these extracted representations. For models in this pipeline, local finer patterns that are crucial to distinguish positive pairs from negative ones cannot be captured, and thus making them underperformed. In this paper, we propose a novel deep multiplicative integration gating function, which answers the question of what-and-where to match for effective person re-id. To address what to match, our deep network emphasizes common local patterns by learning joint representations in a multiplicative way. The network comprises two Convolutional Neural Networks (CNNs) to extract convolutional activations, and generates relevant descriptors for pedestrian matching. This leads to flexible representations for pair-wise images. To address where to match, we combat the spatial misalignment by performing spatially recurrent pooling via a four-directional recurrent neural network to impose spatial dependency over all positions with respect to the entire image. The proposed network is designed to be end-to-end trainable to characterize local pairwise feature interactions in a spatially aligned manner. To demonstrate the superiority of our method, extensive experiments are conducted over three benchmark data sets: VIPeR, CUHK03 and Market-1501.

Logic Gate Functions Built with Nonvolatile Resistive Switching and Thermoresponsive Memory Based on Biologic Proteins.

Logic gate functions built with nonvolatile resistive switching and thermoresponsive memory based on biologic proteins were investigated. The "NAND" and "NOR" functions of logic gates in soya protein devices have been built at room temperature by their nonvolatile ternary WORM resistive switching behaviors. Furthermore, heating the devices from room temperature to 358 K results in a switch from tristable state to bistable state WORM resistive switching behavior, indicating that the thermoresponsiveness can be efficiently memorized. The biologic transient nonvolatile memory device consisting of soya protein is illustrated. This device exhibits a long data retention time (104 s) and significant HRS/LRS ratio (∼105); the transient response of the current to voltage of an as-fabricated device is also explored. The soya protein based memory device on a gelatin film substrate is also assessed to validate the feasibility of degradation and biological compatibility for the implantable biological electronic device, that is, innoxious and avirulent to the human body. This can offer alternative avenues for exploring prospective bioelectronic devices.

Deep supervised learning with mixture of neural networks.

Deep Neural Network (DNN), as a deep architectures, has shown excellent performance in classification tasks. However, when the data has different distributions or contains some latent non-observed factors, it is difficult for DNN to train a single model to perform well on the classification tasks. In this paper, we propose mixture model based on DNNs (MoNNs), a supervised approach to perform classification tasks with a gating network and multiple local expert models. We use a neural network as a gating function and use DNNs as local expert models. The gating network split the heterogeneous data into several homogeneous components. DNNs are combined to perform classification tasks in each component. Moreover, we use EM (Expectation Maximization) as an optimization algorithm. Experiments proved that our MoNNs outperformed the other compared methods on determination of diabetes, determination of benign or malignant breast cancer, and handwriting recognition. Therefore, the MoNNs can solve the problem of data heterogeneity and have a good effect on classification tasks.