Circuitry Operating Research Articles

High-dimensional cortical signals reveal rich bimodal and working memory-like representations among S1 neuron populations

Complexity is important for flexibility of natural behavior and for the remarkably efficient learning of the brain. Here we assessed the signal complexity among neuron populations in somatosensory cortex (S1). To maximize our chances of capturing population-level signal complexity, we used highly repeatable resolvable visual, tactile, and visuo-tactile inputs and neuronal unit activity recorded at high temporal resolution. We found the state space of the spontaneous activity to be extremely high-dimensional in S1 populations. Their processing of tactile inputs was profoundly modulated by visual inputs and even fine nuances of visual input patterns were separated. Moreover, the dynamic activity states of the S1 neuron population signaled the preceding specific input long after the stimulation had terminated, i.e., resident information that could be a substrate for a working memory. Hence, the recorded high-dimensional representations carried rich multimodal and internal working memory-like signals supporting high complexity in cortical circuitry operation.

Development of charge-discharge circuitry based on supercapacitor and its application to limiter probe diagnostics in EAST

The EAST limiter probe is installed on the front surface of guard limiter, which consists of two columns and can operate in floating potential mode, ion saturation current mode, and swept single-probe mode simultaneously. When Langmuir probe operates in the ion saturation current mode, it requires a stable biasing voltage. To meet this requirement, a large capacitor is used to provide a biasing voltage for the probe. Comparing with the 9 V dry batteries that are commonly used in magnetic confinement fusion devices, employing a large capacitor offers advantages such as flexible voltage adjustment, easy maintenance, and environmental friendliness. Therefore, we have designed and tested a complete set of supercapacitor charge-discharge control circuitry. In this work, a control software is developed for the supercapacitor charge-discharge control circuitry based on the Python language to enable the remote and automatic controlling of the circuitry operation. As demonstrated in experiments, the capacitor charge-discharge control circuitry can supply stable biasing voltage output for the probe under long-pulse discharge, and it is workable in complex electromagnetic environment of magnetic confinement fusion device. By implementing the supercapacitor charge-discharge control circuitry in EAST limiter probe diagnostics, the three-dimensional distributions of plasma parameters are measured, such as ion saturation current, floating potential, electron temperature, and plasma density. In a lower hybrid wave (LHW) heating experiment, the 2.45 GHz LHW is found to generate larger electron density than the 4.6 GHz LHW, and the largest electron density appears when both the 2.45 GHz and 4.6 GHz LHWs are turned on simultaneously. These experimental results confirm that supercapacitor charge-discharge control circuitry can be operated reliably and stably.

PPARγ and NOTCH Regulate Regional Identity in the Murine Cardiac Outflow Tract.

The arterial pole of the heart is a hotspot for life-threatening forms of congenital heart defects (CHDs). Development of this cardiac region occurs by addition of Second Heart Field (SHF) progenitor cells to the embryonic outflow tract (OFT) and subsequently the base of the ascending aorta and pulmonary trunk. Understanding the cellular and genetic mechanisms driving arterial pole morphogenesis is essential to provide further insights into the cause of CHDs. A synergistic combination of bioinformatic analysis and mouse genetics as well as embryo and explant culture experiments were used to dissect the cross-regulatory transcriptional circuitry operating in future subaortic and subpulmonary OFT myocardium. Here, we show that the lipid sensor PPARγ (peroxisome proliferator-activated receptor gamma) is expressed in future subpulmonary myocardium in the inferior wall of the OFT and that PPARγ signaling-related genes display regionalized OFT expression regulated by the transcription factor TBX1 (T-box transcription factor 1). Modulating PPARγ activity in ex vivo cultured embryos treated with a PPARγ agonist or antagonist or deleting Pparγ in cardiac progenitor cells using Mesp1-Cre reveals that Pparγ is required for addition of future subpulmonary myocardium and normal arterial pole development. Additionally, the non-canonical DLK1 (delta-like noncanonical Notch ligand 1)/NOTCH (Notch receptor 1)/HES1 (Hes family bHLH transcription factor 1) pathway negatively regulates Pparγ in future subaortic myocardium in the superior OFT wall. Together these results identify Pparγ as a regulator of regional transcriptional identity in the developing heart, providing new insights into gene interactions involved in congenital heart defects.

WITHDRAWN: A high gain multi-port bidirectional converter with reduced voltage stress

Abstract The energy storage becomes an essential part to exploit the intermittent form of renewable resources more effectively. Further it is mandate for a battery source to have a built in port for charging and discharging phenomena. A novel idea on multi port non-isolated bidirectional converter (M-NIBC) is proposed and experimented for improved voltage gain and reduced voltage stress in this paper. M-NIBC topology is devised with four electronic switches with a freewheeling diode across each and moreover two inductors and three capacitors certainly make the passive circuitry operation. Energy derived from the regenerative braking is sufficient to charge the battery and it can be done through the feedback control of bidirectional power flow. The voltage is shared in the respective module and thereby the stress across the switch is minimized to an extent. The successive reduction in voltage stress controls the ON state resistance of the semiconductor device eventually. Voltage gain of the proposed M-NIBC is comparatively lower than the conventional cascaded bidirectional converter (CBC) during the charging cycle whereas it is relatively higher in discharging cycle. The proposed M-NIBC is configured in a simpler way to control and this approach is tested in the simulation laboratory for validating its novel performance under the charging and discharging cycles respectively.

SMaRT lncRNA controls translation of a G‐quadruplex‐containing mRNA antagonizing the DHX36 helicase

Guanine‐quadruplexes (G4) included in RNA molecules exert several functions in controlling gene expression at post‐transcriptional level; however, the molecular mechanisms of G4‐mediated regulation are still poorly understood. Here, we describe a regulatory circuitry operating in the early phases of murine muscle differentiation in which a long non‐coding RNA (SMaRT) base pairs with a G4‐containing mRNA (Mlx‐γ) and represses its translation by counteracting the activity of the DHX36 RNA helicase. The time‐restricted, specific effect of lnc‐SMaRT on the translation of Mlx‐γ isoform modulates the general subcellular localization of total MLX proteins, impacting on their transcriptional output and promoting proper myogenesis and mature myotube formation. Therefore, the circuitry made of lnc‐SMaRT, Mlx‐γ, and DHX36 not only plays an important role in the control of myogenesis but also unravels a molecular mechanism where G4 structures and G4 unwinding activities are regulated in living cells.

Line-defect photonic crystal terahertz quantum cascade laser

The terahertz (THz) quantum cascade laser (QCL) provides a versatile tool in a plethora of applications ranging from spectroscopy to astronomy and communications. In many of these fields, compactness, single mode frequency emission, and low threshold are highly desirable. The proposed approach, based on line defects in a photonic crystal (PhC) matrix, addresses all these features while offering unprecedented capabilities in terms of flexibility, light waveguiding, and emission directionality. Nine line-defect QCLs were realized in a triangular lattice of pillars fabricated in the laser active region (AR), centered around ∼2 THz by tuning the photonic design. A maximal 36% threshold reduction was recorded for these ultraflat dispersion line-defect QCLs in comparison to standard metal-metal QCL. The mode selectivity is an intrinsic property of the chosen fabrication design and has been achieved by lithographically scaling the dimension of the defect pillars and by acting on the PhC parameters in order to match the AR emission bandwidth. The measured line-defect QCLs emitted preferentially in the single frequency mode in the propagation direction throughout the entire dynamic range. An integrated active platform with multiple directional outputs was also fabricated as proof-of-principle to demonstrate the potential of this approach. The presented results pave the way for integrated circuitry operating in the THz regime and for fundamental studies on microcavity lasers.

Configurable error correction of code-division multiplexed TES detectors with a cryotron switch.

The development of a superconducting analog to the transistor with extremely low power dissipation will accelerate the proliferation of low-temperature circuitry operating in the milliKelvin regime. The thin-film, magnetically actuated cryotron switch is a candidate building block for more complicated and flexible milliKelvin circuitry. We demonstrate its utility for implementing reconfigurable circuitry by integrating a cryotron switch into flux-summed code-division SQUID multiplexed readout for large arrays of transition-edge-sensor (TES) microcalorimeters. Code-division multiplexing eliminates the noise penalty of time-division multiplexing while being drop-in compatible with the latter's control electronics. However, code-division multiplexing is susceptible to single-point failure mechanisms which can result in an unconstrained demodulation matrix and the loss of information from many sensing elements. In the event of a failure, the integrated cryotron switch provides a zero-signal output from a single TES, enabling the demodulation matrix used to compute TES signals from SQUID signals to be constrained and data recovered from the remaining sensors. This demonstration of configurable error correction provides both a realworld application of the cryotron switch and a foundation for more complex circuitry at milliKelvin temperatures.

Towards accessible nanophotonics: multimode interferometer on strip-loaded slot waveguide

Nano- and micro-photonics are the key-enabling tools for future integrated components and circuitry operating at low power and high speed. By using a strip-loaded platform, we show how we can dramatically reduce the complexity, in terms of fabrication and tolerances, of the most advanced devices. Different configurations of multimode interference devices are presented. We show the design, fabrication, and optical characterization of these components.

Atomic scale shot-noise using cryogenic MHz circuitry.

By implementing dedicated cryogenic circuitry operating in the MHz regime, we have developed a scanning tunneling microscope (STM) capable of conventional, low frequency (<10 kHz), microscopy as well spectroscopy and shot-noise detection at 1 MHz. After calibrating our AC circuit on a gold surface, we illustrate our capability to detect shot-noise at the atomic scale and at low currents (<1 nA) by simultaneously measuring the atomically resolved differential conductance and shot-noise on the high temperature superconductor Bi2Sr2CaCu2O8+x . We further show our direct sensitivity to the temperature of the tunneling electrons at low voltages. Our MHz circuitry opens up the possibility to study charge and correlation effects at the atomic scale in all materials accessible to STM.

Intracellular Dynamics in Cuneate Nucleus Neurons Support Self-Stabilizing Learning of Generalizable Tactile Representations.

How the brain represents the external world is an unresolved issue for neuroscience, which could provide fundamental insights into brain circuitry operation and solutions for artificial intelligence and robotics. The neurons of the cuneate nucleus form the first interface for the sense of touch in the brain. They were previously shown to have a highly skewed synaptic weight distribution for tactile primary afferent inputs, suggesting that their connectivity is strongly shaped by learning. Here we first characterized the intracellular dynamics and inhibitory synaptic inputs of cuneate neurons in vivo and modeled their integration of tactile sensory inputs. We then replaced the tactile inputs with input from a sensorized bionic fingertip and modeled the learning-induced representations that emerged from varied sensory experiences. The model reproduced both the intrinsic membrane dynamics and the synaptic weight distributions observed in cuneate neurons in vivo. In terms of higher level model properties, individual cuneate neurons learnt to identify specific sets of correlated sensors, which at the population level resulted in a decomposition of the sensor space into its recurring high-dimensional components. Such vector components could be applied to identify both past and novel sensory experiences and likely correspond to the fundamental haptic input features these neurons encode in vivo. In addition, we show that the cuneate learning architecture is robust to a wide range of intrinsic parameter settings due to the neuronal intrinsic dynamics. Therefore, the architecture is a potentially generic solution for forming versatile representations of the external world in different sensor systems.

The Cholinergic Anti-Inflammatory Pathway: A Novel Paradigm for Translational Research in Neuroimmunology

Inflammation is a complex biologic response to gross traumatic injury, endogenous ligands, or exogenous ligands. The inflammatory response is essential for reestablishing organismal homeostasis. It must be meticulously monitored and tightly regulated as over- or under activation of the inflammatory response can cause morbidity and even mortality. Emerging evidence has begun to depict the molecular mechanisms by which inflammation is regulated via the nervous system; that is, inflammation is controlled by neuroimmunologic circuitry operating in a reflexive continuum. Known as the inflammatory reflex arc, this pathway exhibits an afferent and efferent arc: both of which derive from vagal nerve fibers. The afferent arc is comprised of vagal receptors detecting specific ligands indicating injury. An activated afferent arc will initiate the efferent arc, the cholinergic anti-inflammatory pathway, which regulates immunologically-mediated inflammation. Recent research has demonstrated that this pathway can be modulated with vagus nerve stimulation, providing a potential therapeutic option for a variety of inflammatory conditions. Here, we review the neuroimmunological mechanisms of the inflammatory reflex arc. Furthermore, we analyze current research and discuss potential therapeutic implications of the cholinergic antiinflammatory pathway.

Closed circuitry operation influence on microbial electrofermentation: Proton/electron effluxes on electro-fuels productivity

A novel biocatalyzed electrofermentor (BEF) was designed which uncovers the intricate role of biocatalyst involved in cogeneration of electro-fuels (hydrogen and electricity). The specific role of external resistance (Rext, electrical load) on the performance of BEF was evaluated. Four BEFs were operated separately with different resistances (25, 50, 100 and 200Ω) at an organic load of 5g/L. Among the tested conditions, external resistance (R3) with 100Ω revealed maximum power and cumulative H2 production (148mW and 450mL, respectively). The competence of closed circuitry comparatively excelled because it facilitates congenial ambiance for the enriched EAB (electroactive bacteria) resulting high rate of metabolic activity that paves way for higher substrate degradation and electro-fuel productivity. Probing of electron kinetics was studied using voltammetric analyses wherein electron transfer by redox proteins was noticed. The designed BEF is found to be sustainable system for harnessing renewable energy through wastewater treatment.

Adaptive Supply Voltage Management for Low Power Logic Circuitry Operating at Subthreshold

Adaptive Supply Voltage Management for Low Power Logic Circuitry Operating at Subthreshold

Fault Tolerant Design for Magnetic Memories

This study presents a Fault Tolerant memory cores based on the property of Component Reusability, a method for Fault Tolerance for content addressable memories. The memories used in the design are 256, 512, 1024 and 2048 bytes. The fault is injected into the circuitry operation by using Automatic Test Pattern Generators (ATPGs). The design has been implemented in Cadence 90 nm technology and tested with Fault Injection Circuits and ATPG effectiveness was found out to be 100% at a frequency of 500 MHZ.

Polymeric foil optical waveguide with inkjet printed gas sensitive film for colorimetric sensing

The design of low-cost and low-power optical transducers on plastic foil for colorimetric gas sensors is proposed. The transducer was fabricated from PET or PEN foil on which polymeric micro-mirrors and colorimetric film were patterned using additive techniques. It consisted of a planar optical waveguide that was covered with an inkjet printed ammonia sensitive film for its evaluation. A parametric study was performed on the waveguide configuration to reduce the light loss and improve the gas sensing characteristics. The use of polymeric substrate made the device more cost effective and compatible with large scale fabrication, such as roll-to-roll processes. Combined with a low-power interface circuitry operating in pulsed mode, the limit of detection was defined as a function of the power consumption. Sub-ppm concentrations of NH 3 were measured at a consumption of 868 μW. Such potentially low-cost and low-power sensors foresee applications in the field of wireless systems, for environmental and safety monitoring.

Quorum sensing is necessary for the virulence of Pseudomonas aeruginosa during urinary tract infection

Quorum sensing is a signaling pathway used by bacteria to monitor their population density by detecting small diffusible molecules. To understand the role of quorum sensing in pathogenesis of urinary tract infections, wild type Pseudomonas aeruginosa, having both functional las and rhl quorum sensing systems, and its isogenic single and double mutants were used in a mouse model of ascending urinary tract infection. Mice were evaluated on the basis of bacteriological and histopathological examinations, detection of acyl homoserine lactone, and the pathologic index factors of renal and bladder tissue. Single as well as double mutant strains were able to reach renal tissue, but they were not able to multiply and cause tissue damage. Reduced rates of infection, mild histopathologic lesions, and decreased production of pathologic index factors like myeloperoxidase, malondialdehyde, and reactive nitrogen intermediates were found in these groups of mice as compared to mice infected with a standard strain (PAO1) possessing both functional sensing systems. Loss of any one of the quorum-sensing components significantly reduced the in vivo virulence of P. aeruginosa in this mouse model of ascending urinary tract infection. Our results suggests that quorum-sensing signals may act as virulence factors and are essential for P. aeruginosa multiplication and virulence during the course of urinary tract infection.

Animated musical alligator

This invention relates to an animated musical alligator which features movement while playing music. The object of the animated musical alligator is to provide an original, amusing toy and novelty item for adults and children, alike. When it plays songs, mouth movements occur in synchronization with the singing, as a result of its circuitry and mechanical operation system. In addition, the alligator produces realistic walking movements and up-and-down, as well as side-to-side head movements. The invention's integrated circuit, which creates sound signal and movement signal outputs, produces music through its amplifier and speaker. Additionally, the IC activates various motors, which trigger gears to create leg movements and side-to-side and up-and-down head movements. This operation system also creates mouth movements in synchronization with the playing of songs.

High-speed operation of demultiplexer up to 56 GHz

A 1-to-4 demultiplexer (DEMUX) was designed based on Single Flux Quantum (SFQ) circuitry and high-speed operation was confirmed using on-chip testing. The circuit was designed with a binary-tree structure to enable high-speed operation. We also investigated timing between clock and data signals in detail. Monte Carlo simulation was applied to vary the design parameters pseudo-randomly and the spread of timing was obtained by circuit simulation. Even if the circuit parameters varied as a result of the fabrication process, proper timing was maintained by optimizing the length of Josephson transmission line. The 1-to-4 DEMUX we fabricated distributed data signals correctly at operating frequencies up to 56 GHz with a bias margin of /spl plusmn/7%.

Suppressor T cell circuits in contact sensitivity. III. A monoclonal T cell hybrid-derived suppressor factor specifically suppresses local DTH transfer by a DNP-specific T cell clone.

Herein we described the direct suppressive effects of a monoclonal T cell hybridoma-derived, DNP-specific suppressor T cell factor (26.10.2 TsF) on the local transfer of delayed-type hypersensitivity (DTH) by a DNP-specific BALB/c T cell clone (dD1.9). The L3T4+, Lyt-2- dD1.9 T cell clone proliferated in response to DNP-OVA and DNBS, but not TNP-OVA or TNBS, in association with I-Ed determinants present on antigen-presenting cells. Similarly, local injection of histopaque-purified dD1.9 cell blasts resulted in DNP-specific, radioresistant, I-Ed-restricted, mononuclear cell-rich ear swelling responses. Incubation in 26.10.2 TsF specifically suppressed local transfer of DNP-specific DTH by dD1.9, but not local DTH responses transferred by BALB/c T cell clones specific for TNP or GAT. The suppressive effect of 26.10.2 TsF correlated with targeting on DNP-major histocompatibility complex determinants associated with the DTH T cell (TDH) targets. 26.10.2 TsF-mediated suppression was most pronounced after exposure of dD1.9 target cells to antigen (after the stimulation phase of the T cell clone maintenance procedure), and greatly reduced when dD1.9 was cultured for long periods in the absence of DNP (after the rest phase of clone maintenance). In additional support of this hypothesis, GAT-specific TDH, normally resistant to 26.10.2 TsF-mediated suppression, were rendered susceptible to suppression after surface DNPylation. The results demonstrate a direct, antigen-specific, effector phase regulatory effect of a monoclonal TsF on a cloned, antigen-specific T cell target, and strongly suggest that suppression is mediated via targeting on DNP determinants associated with the TDH target. Simplification of complex Ts circuitry operating in suppression of the efferent limb of DTH by the use of monoclonal TsF and cloned T cell targets should provide a basis for the future study of the molecular mechanisms of immune suppression.

100-Mhz 1000-bit ultrasonic digital delay-line time-compression store

Digital information is stored in a recirculating loop that consists of an otc glass delay line and associated circuitry operating in the 100mhz range. A maximum retiming margin of 67 % was observed. The circuitry is designed to use only those components that can be implemented using integrated-circuit technology; all critical tolerances are related to component parameter ratios. A minimum retiming margin of 54 % is expected for typical ic tolerances. The economical advantages of operating the loop at 100 mhz, the size of the store, and the 1000-bits storage capacity can be retained at considerably lower external bit rates if sequential bit locations are accessed only one per n recirculation cycles (n=1,2,3,...). This generalized deltic access mode has potential use in speed converting buffer stores between fast computer processors and slower peripheral data-processing devices.