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Due to effects of the gating ratio on the amount of shrinkage porosities and thereby on mechanical properties of steel components, optimizing the gating system is one of the interested fields for scientists focused on the casting industry. In this paper, the casting of a steel centrifugal pump body has been simulated and influences of the gating ratio on the casting quality of the obtained component have been evaluated. Investigated parameters involve the place of formed hot-spots, the speed of the liquid flowing from gates and its uniformity. The obtained results show that in the case of the evaluated component, both of the suggested gating ratios of 2:1.15 and 1:3:3 can distribute the melt well in such a way that the last solidified parts are far from the portions experiencing high stresses during the service. However, using the gating ratio of 1:2:1.5 lets that the sprue to be full of the liquid metal. So, the sprue can compensate the occurred shrinkage and almost prevent the entrance of the out gases. Moreover, it was observed that the symmetry of gates with respect to each other does not have an important effect but with respect to the position of the sprue has a crucial role to ensure a similar speed and behavior of the metal flowing in the different gates. [ABSTRACT FROM AUTHOR]

Submitted work deals with the analysis of reoxidation processes for aluminium alloys. Due to the aluminium high affinity to the oxygen, the oxidation and consequently reoxidation will occur. Paper focuses on the gating system design in order to suppress and minimize reoxidation processes. Design of the gating system is considered as one of the most important aspect, which can reduce the presence of reoxidation products - bifilms. The main reason for the reoxidation occurrence is turbulence during filling of the mold. By correctly designing the individual parts of gating system, it is possible to minimize turbulence and to ensure a smooth process of the mold filling. The aim of the work is an innovative approach in the construction of gating system by using unconventional elements, such as a naturally pressurized system or vortex elements. The aim is also to clarify the phenomenon during the gating system filling by visualization with the aid of ProCAST numerical simulation software. ProCAST can calculate different indicators which allow to better quantify the filling pattern. [ABSTRACT FROM AUTHOR]

We present and analyze a gated single photon avalanche detector using a sine gating scheme with a simple but effective low-pass filtering technique for fast low-noise single photon detection at telecom wavelength. The detector is characterized by 130 ps short gates applied with a frequency of 1.25 GHz, yields only 70 ps timing jitter and noise probabilities as low as 7·10-7 per gate at 10% detection efficiency. We show that the detector is suitable for high rate quantum key distribution (QKD) and even at room temperature it could allow for QKD over distances larger than 25 km. [ABSTRACT FROM AUTHOR]

In this work we have developed a method to covalently attach butylamine molecules to the sidewall of single-walled carbon nanotubes (SWNTs) starting from fluorinated SWNTs (F-SWNTs) obtained by CF4 plasma treatment at room temperature. Scanning tunneling microscopy images demonstrate that after the sidewall fluorination of SWNTs some bundles with a lower number of single tubes are present. The subsequent amine functionalization of the tubes has been demonstrated by infrared spectroscopy and thermogravimetric measurements. The chemical adsorption of butylamine molecules on F-SWNTs has been also investigated by electrical transport measurements in thin-film transistor geometry. The electrical conductance of SWNTs decreases after adsorption of butylamine. The amine groups in the molecule are electron donating and the observed photoconductivity of amino-functionalized F-SWNTs is presumably due to the injection of electrons from amine groups to SWNTs. [ABSTRACT FROM AUTHOR]

As a member of the transient receptor potential (TRP) channels superfamily, the TRPV1 channel undergoes a closed-to-open gating transition in response to various physical and chemical stimuli including heat. Thanks to recent progress in cryo-electron microscopy, high-resolution structures are becoming available for various TRP channels including TRPV1. This has enabled us to study the molecular mechanism of TRPV1 channel gating by using molecular simulation. Here we review recent progress in molecular simulations of TRPV1 channel by us and others, with focus on our molecular dynamics (MD) simulations of TRPV1 at different temperatures. While no consensus has been reached on the heat activation mechanism of TRPV1, the simulations have offered specific predictions and models for future experimental studies to test. [ABSTRACT FROM AUTHOR]

Background: Automatic extraction of chemical-disease relations (CDR) from unstructured text is of essential importance for disease treatment and drug development. Meanwhile, biomedical experts have built many highly-structured knowledge bases (KBs), which contain prior knowledge about chemicals and diseases. Prior knowledge provides strong support for CDR extraction. How to make full use of it is worth studying. Results: This paper proposes a novel model called "Knowledge-guided Convolutional Networks (KCN)" to leverage prior knowledge for CDR extraction. The proposed model first learns knowledge representations including entity embeddings and relation embeddings from KBs. Then, entity embeddings are used to control the propagation of context features towards a chemical-disease pair with gated convolutions. After that, relation embeddings are employed to further capture the weighted context features by a shared attention pooling. Finally, the weighted context features containing additional knowledge information are used for CDR extraction. Experiments on the BioCreative V CDR dataset show that the proposed KCN achieves 71.28% F1-score, which outperforms most of the state-of-the-art systems. Conclusions: This paper proposes a novel CDR extraction model KCN to make full use of prior knowledge. Experimental results demonstrate that KCN could effectively integrate prior knowledge and contexts for the performance improvement. [ABSTRACT FROM AUTHOR]

Air entrainment during mold filling is a major source of oxide inclusion formation in metal casting. A model was recently developed by the authors to predict the volumetric air entrainment during pouring of metal castings. In the course of validating the model with experimental data for plunging liquid jets, it was shown that the air entrainment rate during mold filling depends fundamentally on the velocity and diameter of the jet formed by the pouring stream. In this study, the effect of more complex pouring conditions and gating system design on air entrainment is examined. Simulations are performed investigating the air entrainment characteristics of castings filled without a gating system, and with bottom-gated and side-gated filling systems. Results indicate that reducing the head height and pouring time, and the addition of a nozzle extension significantly reduces the air entrainment. In addition, using an offset pouring basin with a stopper and pressurizing the gating system further reduces the volume of entrained air. Simulation results also show that the generation of vortex flows inside the filling system is beneficial in reducing free surface turbulence, which results in less air entrainment and oxide inclusion formation during mold filling. [ABSTRACT FROM AUTHOR]

Chemical detection has a wide range of applications. The detection of a certain substance is so vital that new detection mechanisms with features such as low‐cost, accessibility, and readily available visual markers are in demand. Herein, a liquid‐gating‐based chemical‐detection mechanism is reported, which has a dynamic gas/liquid interface due to dipole‐induced interfacial molecular reconfiguration. The mechanism exhibits a sensitive relationship between the dipole‐force‐induced rearrangement of interfacial molecules and transmembrane gating behavior. These features can be utilized to create visual markers for detection by converting the analyte‐mediated interfacial interaction to a pressure‐driven marker movement. This "green" detection mechanism requires no electrical energy input and has readily available markers for anyone to observe directly. This new mechanism opens a window for a more in‐depth exploration of combining liquid‐gating mechanisms with detection mechanisms. [ABSTRACT FROM AUTHOR]

Abstract Recurrent Neural Network (RNN) based approaches have recently shown promising in tackling Natural Language Generation (NLG) problems. This paper presents an approach to leverage gating mechanisms, in which we incrementally propose three additional semantic cells into a traditional RNN model: a Refinement cell to filter the sequential inputs before RNN computations, an Adjustment cell, and an Output cell to select semantic elements and gate a feature vector during generation. The proposed gating-based generators can learn from unaligned data by jointly training both sentence planning and surface realization to generate natural language utterances. We conducted extensive experiments on four different NLG domains in which the results empirically show that the proposed methods not only achieved better performance on all the NLG domains in comparison with previous gating-based, attention-based methods, but also obtained highly competitive results compared to a hybrid generator. [ABSTRACT FROM AUTHOR]

The integration of multiple sensory modalities allows us to adapt to the environment of the outside world. It is widely known that visual stimuli interfere with the processing of auditory information, which is involved in the ability to pay attention. Additionally, visuospatial attention has the characteristic of laterality. It is unclear whether this laterality of visuospatial attention affects the processing of auditory stimuli. The sensorimotor gating system is a neurological process, which filters out unnecessary stimuli from environmental stimuli in the brain. Prepulse inhibition (PPI) is an operational measure of the sensorimotor gating system, which a weaker prestimulus (prepulse), such as a visual stimulus, inhibits the startle reflex elicited by a subsequent robust startling stimulus (pulse) such as a tone. Therefore, we investigated whether the visual stimulus from the left or right visual space affects the sensorimotor gating system in a "rest" task (low attentional condition) and a "selective attention" task (high attentional condition). In the selective attention task, we found that the target prepulse presented in the left and bilateral visual fields suppressed the startle reflex more than that presented in the right visual field. By contrast, there was no laterality of PPI in the no-target prepulse condition, and there was no laterality of PPI in the rest task. These results suggest that the laterality of visuospatial attention affects the sensorimotor gating system depending on the attentional condition. Moreover, the process of visual information processing may differ between the left and right brain. [ABSTRACT FROM AUTHOR]

Abstract P2X receptors are a family of extracellular ATP-gated trimeric cation channels that is widely distributed in human tissues. Quite some drug candidates targeting P2X receptors have entered into preclinical or main phases of clinical trials, but many of them failed due to low subtype-selectivity or species differences in pharmacological activities between human and experimental animals. Here, we identified the distinct inhibitory efficacies of NF110, a competitive inhibitor, between the rat (rP2X3) and human (hP2X3) P2X3 receptors. We demonstrated that this difference is determined by two amino acids located in the dorsal fin (DF) domain of P2X3 receptors. As revealed by mutagenesis, metadynamics, and covalent modification, NF110-mediated rP2X3 inhibition may be through a filling in the cavity formed by the DF, left flipper (LF) and lower body (LB) to partially, rather than fully, occupy the ATP-binding pocket. Moreover, substitution of residues located in the DF and/or LF domains of the rP2X2 receptor, a NF110-insensitive subtype, with the equivalent amino acids of rP2X3, bestowed the sensitivity of rP2X2 to NF110. The critical roles of the DF and LF domains in channel gating of P2X and low conservativity in residue sequences of those two domains raise the possibility that small molecules differentially interacting with the residues of the DF and LF domains of different P2X receptors may modulate channel's activity in a subtype-selective manner. However, the possible species-specificity of P2X inhibitors/modulators makes it more complex when interpreting the preclinical data into clinical researches. Nevertheless, our data provide new insights into the subtype-selectivity of competitive inhibitors and their distinct potencies in the human and experimental animals, both of which are extremely important in the drug discovery of P2X receptors. [ABSTRACT FROM AUTHOR]

Abstract Multi-person activity recognition is a challenging task due to its elusive interactions in activities. We take into account these interactions at two levels. At the individual level, each person behaves depending on both its spatio-temporal features and interactions propagated from others in the scene. At the scene level, the multi-person activity is characterized by interactions between individuals' actions and the high-level activity. It is worth noting that interactions contribute unequally at both levels. To jointly explore these colorful interactions, we propose a two-level attention-based interaction model relying on two time-varying attention mechanisms. The individual-level attention mechanism conditioned on pose features, exploits various degrees of interactions among individuals in a scene while updating their states at each time step. The scene-level attention mechanism proposes an attention-based pooling strategy to explore various levels of interactions between individuals' actions and the high-level activity. We ground our model by a modified two-stage Gated Recurrent Units (GRUs) network to handle the long-range temporal variability and consistency. Our end-to-end trainable model takes as inputs a set of person detections in videos or image sequences and predicts labels of multi-person activities. Experimental results demonstrate comparable performance of our model and show the effectiveness of our attention mechanisms. [ABSTRACT FROM AUTHOR]

We investigate the possibility that slow metabolic, cell-cycle-related oscillations in yeast and associated temporal clustering of cells within the cell cycle could be due to an interplay between near-critical metabolism and cell cycle checkpoints. We construct a dynamical model of the cell cycles of a large culture of cells that incorporates checkpoint gating and metabolic mode switching that are triggered by resource thresholds. We investigate the model analytically and prove that there exist open sets of parameter values for which the model possesses stable periodic solutions that exhibit metabolic oscillations with cell cycle clustering. Simulations of the model give evidence that such solutions exist for large sets of parameter values. This demonstrates that checkpoint gating coupled with critical resources can be a robust mechanism for producing the phenomena observed in experiments. [ABSTRACT FROM AUTHOR]

Purpose: To develop and validate a technique for radiation therapy gating using slow (≤1 frame per second) magnetic resonance imaging (MRI) and a motion model. Proposed uses of the technique include radiation therapy gating using T2-weighted images and conducting additional imaging studies during gated treatments.Methods and Materials: The technique uses a physiologically guided breathing motion model to interpolate deformed target position between 2-dimensional (2D) MRI images acquired every 1 to 3 seconds. The model is parameterized by a 1-dimensional respiratory bellows surrogate and is continuously updated with the most recently acquired 2D images. A phantom and 8 volunteers were imaged with a 0.35T MRI-guided radiation therapy system. A balanced steady-state free precession sequence with a 2D frame rate of 3 frames per second was used to evaluate the technique. The accuracy and beam-on positive predictive value (PPV) of the model-based gating decisions were evaluated using the gating decisions derived from imaging as a ground truth. A T2-weighted gating offline proof-of-concept study using a half-Fourier, single-shot, turbo-spin echo sequence is reported.Results: Model-interpolated gating accuracy, beam-on PPV, and median absolute distances between model and image-tracked target centroids were, on average, 98.3%, 98.4%, and 0.33 mm, respectively, in the balanced steady-state free precession phantom studies and 93.7%, 92.1%, and 0.86 mm, respectively, in the volunteer studies. T2 model-interpolated gating in 6 volunteers yielded an average accuracy and PPV of 94.3% and 92.5%, respectively, and the mean absolute median distance between modeled and imaged target centroids was 0.86 mm.Conclusions: This work demonstrates the concept of model-interpolated gating for MRI-guided radiation therapy. The technique was found to be potentially sufficiently accurate for clinical use. Further development is needed to accommodate out-of-plane motion and the use of an internal MR-based respiratory surrogate. [ABSTRACT FROM AUTHOR]

High pressure die casting (HPDC) is a kind of near net shape manufacturing method. However, air entrapment in HPDC parts has serious effects upon the casting quality. In order to reduce the air entrapment defects in a AlSi10MnMg alloy thin-wall longitudinal load-bearing beam produced by HPDC, different gating systems were designed and simulated by software Flow-3D to evaluate the entrapped air. Simulation results showed that when the beam is produced by the original designed gating system with a middle ingate, there exist obvious air entrapments in the critical area; the volume of air entrapment was reduced by replacing the middle ingate to an overflow well, and the filling of molten metal became more stable. When the middle ingate was removed for further improvement, the volume of air entrapment was decreased drastically. The parts with glossy surface and good microstructure have been successfully produced by using the final optimized gating system based on simulation results. [ABSTRACT FROM AUTHOR]

The design of gating system occupies a very important proportion in the design of the entire casting process. Casting solidification simulation is being a deterministic approach replacing the iterative trial and error method to design gating system in investment casting. However, the experience and knowledge of the engineer have an important impact on the effectiveness to achieving an optimal solution. The purpose of this paper is to get an optimized gating system to decreasing the size of the riser with a safety margin design with no shrinkage cavities and porosities in the impeller. The Box-Behnken Design (BBD) was prepared with three experimental factors and two optimal targets. The experimental factors involved gating system diameter, gating system height, and pouring temperature for open impeller. The targets included volume of shrinkage porosity and distance from shrinkage porosity to casting. The results indicated that the diameter of the riser has the most obvious impact on the volume and position of the shrinkage porosity. Compared with the riser obtained by the modulus method, the results show that the effect of riser optimization is more obvious, the volume of gating system is reduced by 47.85%, and the casting yield is increased by 15.02%. The physical experiments were performed to verify the simulation results, and good agreement between experimental values. [ABSTRACT FROM AUTHOR]

Computer modeling using a commercially available software package was used to explore the optimization of filling systems based on the relatively new concepts of avoiding entrainment of air bubbles and oxides by avoiding surface turbulence. The test casting was based on a pattern for a traditional top poured test bar, whose cross section was a tri-lobed clover-like shape. The study illustrates clearly that the detailed design of the filling system has a major influence on the conditions for defect generation during filling. Traditional steel casting systems using the widely popular assembly of preformed refractory tubes were found to behave poorly. Systems were demonstrated which were capable of delivering highly controlled filling behavior. The latest systems to be developed employed (1) a naturally pressurized filling system and (2) the use of filters placed flush on the top of the runner to act as bubble diverters, together with (3) terminal spin traps. These novel filling systems demonstrated excellent performance in simulation, in agreement with practical experience of the capability (of the trident gate in particular) to produce, for the first time in the history of casting, defect-free castings on a routine basis. [ABSTRACT FROM AUTHOR]

An attempt is made to analyse the performance of an external gate feeder for headed parts (rivets, bolts, etc.). A model is developed to study the effect of different parameters on its performance. The feeder was fabricated and its performance was studied to verify the proposed model. The model covers a wide range of working. [ABSTRACT FROM AUTHOR]

Purpose: Data‐driven gating (DDG) approaches for positron emission tomography (PET) are interesting alternatives to conventional hardware‐based gating methods. In DDG, the measured PET data themselves are utilized to calculate a respiratory signal, that is, subsequently used for gating purposes. The success of gating is then highly dependent on the statistical quality of the PET data. In this study, we investigate how this quality determines signal noise and thus motion resolution in clinical PET scans using a center‐of‐mass‐based (COM) DDG approach, specifically with regard to motion management of target structures in future radiotherapy planning applications. Methods: PET list mode datasets acquired in one bed position of 19 different radiotherapy patients undergoing pretreatment [18F]FDG PET/CT or [18F]FDG PET/MRI were included into this retrospective study. All scans were performed over a region with organs (myocardium, kidneys) or tumor lesions of high tracer uptake and under free breathing. Aside from the original list mode data, datasets with progressively decreasing PET statistics were generated. From these, COM DDG signals were derived for subsequent amplitude‐based gating of the original list mode file. The apparent respiratory shift d from end‐expiration to end‐inspiration was determined from the gated images and expressed as a function of signal‐to‐noise ratio SNR of the determined gating signals. This relation was tested against additional 25 [18F]FDG PET/MRI list mode datasets where high‐precision MR navigator‐like respiratory signals were available as reference signal for respiratory gating of PET data, and data from a dedicated thorax phantom scan. Results: All original 19 high‐quality list mode datasets demonstrated the same behavior in terms of motion resolution when reducing the amount of list mode events for DDG signal generation. Ratios and directions of respiratory shifts between end‐respiratory gates and the respective nongated image were constant over all statistic levels. Motion resolution d/dmax could be modeled as d / d max = 1 − e − 1.52 ( S N R − 1 ) 0.52, with dmax as the actual respiratory shift. Determining dmax from d and SNR in the 25 test datasets and the phantom scan demonstrated no significant differences to the MR navigator‐derived shift values and the predefined shift, respectively. Conclusions: The SNR can serve as a general metric to assess the success of COM‐based DDG, even in different scanners and patients. The derived formula for motion resolution can be used to estimate the actual motion extent reasonably well in cases of limited PET raw data statistics. This may be of interest for individualized radiotherapy treatment planning procedures of target structures subjected to respiratory motion. [ABSTRACT FROM AUTHOR]

Nowadays, there are growing demands on the accuracy of production. Most of this is reflected in precise manufacturing, such as the investment casting process. Foundries are looking for causes of defects in some cases for a very long time, and it may happen that the source of defects is completely different from what was originally assumed. During the casting process there exist potential causes of defects as oxygen inclusions. This paper represents a summary of the beginnings of a wider research that will address the problems of gating systems in investment casting technology. In general, the influence of the melt flow is underestimated and the aim of the whole scientific research is to demonstrate the significant influence of laminar or turbulent flow on the resulting casting quality. Specifically, the paper deals with the analysis of the most frequent types of defects found in castings made of expensive types of materials casted in an open atmosphere and demonstration of connection with the design of gating systems in the future. [ABSTRACT FROM AUTHOR]

Based on the structural characteristics of parts and the metal powders plus polyamide molding characteristics, a metal-powder injection mold was designed, and its molding parts, side core-pulling mechanism, gating system, die release mechanism, fixed distance classification mechanism, orientation system and temperature control system were mainly studied to determine a reasonable mold structure. Through designing a combined structure of hot runner casting, two ejection mechanisms and straight pipe plus buffle-type well cooling water channel, the molded part achieved dimensional tolerance in the range of 0.4% of the basic dimension. Moreover, the angle tolerance and surface roughness reached 0.5° and 0.8, respectively. [ABSTRACT FROM AUTHOR]

A novel dual pH-responsive smart gating membrane is proposed for the first time by skillfully blending poly( N,N ′-dimethylamino-2-ethyl methacrylate) (PDMAEMA) microgels into poly(ether sulfone) membrane as functional gates via liquid-induced phase separation method. The as-prepared membrane exhibits dual pH-responsive characteristics, i.e., this novel membrane is featured with both positively pH-responsive characteristics in acidic environment and negatively pH-responsive characteristics in basic environment. The mechanism of the positively pH-responsive performance is attributed to the pH-responsive volume change of PDMAEMA microgels embedded in the membrane, while that of the negatively pH-responsive performance is originated from the pH-responsive hydrophobicity and stiffness of the microgels. As a result, the permeability of this novel membrane is increased at first and then decreased with increasing the environmental pH value. The dual pH-responsive property of the prepared membrane is reversible and repeatable. The dual pH-responsive membrane proposed in this study provides a novel gating mode for design and development of pH-responsive smart membranes, which is highly potential for myriad applications, such as sewage treatments, sensors, controlled release of drugs and so on. [ABSTRACT FROM AUTHOR]

In order to study the effects of various gating systems on the casting of a complex aluminum alloyed multi-way valve body, both software simulation analysis and optimization were carried out. Following, the aluminum alloyed multi-way valve body was cast to check the pouring of the aluminum alloy valve body. The computer simulation results demonstrated that compared to the single side casting mode, the casting method of both sides of the gating system would reduce the filling of the external gas, while the air contact time would be lower. Adversely, due to the pouring on both sides, the melt cannot reach at the same time, leading to the liquid metal speed into the cavity to differ, which affected the liquid metal filling stability. The riser unreasonable setting led to the solidification time extension, resulting in a high amount of casting defects during solidification. Also, both gating systems led the entire casting inconsequential solidification. To overcome the latter problems, a straight gate was set at the middle pouring and the horizontal gate diversion occurred on both sides of pouring, which could provide better casting results for the aluminum alloyed multi-valve body. [ABSTRACT FROM AUTHOR]

Gating pore currents through the voltage-sensing domains (VSDs) of the skeletal muscle voltage-gated sodium channel NaV1.4 underlie hypokalemic periodic paralysis (HypoPP) type 2. Gating modifier toxins target ion channels by modifying the function of the VSDs. We tested the hypothesis that these toxins could function as blockers of the pathogenic gating pore currents. We report that a crab spider toxin Hm-3 from Heriaeus melloteei can inhibit gating pore currents due to mutations affecting the second arginine residue in the S4 helix of VSD-I that we have found in patients with HypoPP and describe here. NMR studies show that Hm-3 partitions into micelles through a hydrophobic cluster formed by aromatic residues and reveal complex formation with VSD-I through electrostatic and hydrophobic interactions with the S3b helix and the S3-S4 extracellular loop. Our data identify VSD-I as a specific binding site for neurotoxins on sodium channels. Gating modifier toxins may constitute useful hits for the treatment of HypoPP. [ABSTRACT FROM AUTHOR]

Kv11.1 (hERG, KCNH2) is a voltage-gated potassium channel crucial in setting the cardiac rhythm and the electrical behaviour of several non-cardiac cell types. Voltage-dependent gating of Kv11.1 can be reconstructed from non-covalently linked voltage sensing and pore modules (split channels), challenging classical views of voltage-dependent channel activation based on a S4–S5 linker acting as a rigid mechanical lever to open the gate. Progressive displacement of the split position from the end to the beginning of the S4–S5 linker induces an increasing negative shift in activation voltage dependence, a reduced zg value and a more negative ΔG0 for current activation, an almost complete abolition of the activation time course sigmoid shape and a slowing of the voltage-dependent deactivation. Channels disconnected at the S4–S5 linker near the S4 helix show a destabilization of the closed state(s). Furthermore, the isochronal ion current mode shift magnitude is clearly reduced in the different splits. Interestingly, the progressive modifications of voltage dependence activation gating by changing the split position are accompanied by a shift in the voltage-dependent availability to a methanethiosulfonate reagent of a Cys introduced at the upper S4 helix. Our data demonstrate for the first time that alterations in the covalent connection between the voltage sensor and the pore domains impact on the structural reorganizations of the voltage sensor domain. Also, they support the hypothesis that the S4–S5 linker integrates signals coming from other cytoplasmic domains that constitute either an important component or a crucial regulator of the gating machinery in Kv11.1 and other KCNH channels. [ABSTRACT FROM AUTHOR]

This article presents a scalable power-gating scheme approach to reduce leakage power using intermediate poweroff modes. An important limitation in power-gating scheme is its variations with wakeup time during activation mode changes, as is often the case. The authors have proposed a novel power-gating scheme that are accomplished by hierarchical mode activation to reduce worst case delay bound. The system combines the advantages of leakage power reduction and wake up time optimization. The influence of power-gating scheme on circuit performance is studied and concluded that finite power-off modes, scalable modes are important for good performance. Key selection of power-off modes over entire circuit is complex and it is computationally more expensive. To get more accurate modes with finite trade off in wake up time, this new approach gives near-perfect ways of isolating modes from other changes. The complete power-gating scheme system was evaluated on a multiplier logic core as a test sample and also compared against well known power-gating schemes. [ABSTRACT FROM AUTHOR]

The objective of this research is to propose an integrating modeling mechanism for three-dimensional casting process model (TDCPM) based on model-based definition (MBD). Firstly, the structure of the three-dimensional casting process model is put forward, and the TDCPMis comprised of three components: (1) process geometry model, (2) process information, and (3) process dimension information, building the relationship between the three components and give the planning procedure. Secondly, research the construction process of the casting part, gating system, and risering system; provide data structure, analysis method, and rebuilding mechanism of process dimension information; and introduce the casting process parameter and process planning history mechanism for TDCPM. Finally, a casting process planning system prototype is developed based on the proposed modeling mechanism. [ABSTRACT FROM AUTHOR]

The preparation process of complex thin-wall magnesium alloy castings based on numerical simulation and rapid prototyping core making method is presented in this paper. The filling and solidification processes were simulated using ProCAST to optimise the gating system. The simulation results showed that compared with bottom gating system, vertical slitting gating system equipped with a slot ingate and slag tank contributed to provide a stable filling pattern and eliminate casting porosity. Additionally, Profile Failure-based Rapid Prototyping (PFRP) technology was adopted to obtain sand cores due to its complexity. Mg-4.2Zn-1.7Ce-0.8Zr-0.2Ca-0.2Sr (wt.%) alloy was selected as the alloy material because of the excellent fluidity and flame retardancy. JMatPro was utilized to calculate thermo-physical properties of the alloy to ensure the simulation validity. Casting experiments were conducted, indicating that numerical predictions agreed well with experimental results. Sound thin-wall accessory gearbox casting was obtained based on the optimised gating system and PFRP-fabricated sand cores. [ABSTRACT FROM AUTHOR]

Sweden does not have gated communities, but this paper argues that processes of gating and the associated consequences are apparent in Sweden, particularly in metropolitan regions. Based on interviews, observations and analysis of previous research, the article identifies the rise of urban gating and gated housing. Urban gating restricts access to previously public land through material gating and results in a loss of the right to use-value of urban land. The rise of a new and exclusive form of gated housing associated with the lifestyles of the mobile middle class, referred to here, as the residential hotel, is spotlighted, prompting questions about the concentration of affluence in already privileged areas and the reinforcing effect of gating on existing patterns of socio-spatial polarization. [ABSTRACT FROM PUBLISHER]

The presented paper describes a study concerning the synthesis of copper nitride layers by means of the pulsed magnetron sputtering (PMS) method that can work under conditions of various frequencies of modulation. The morphology and phase composition of the layers were determined as a function of the process parameters: the power ( P ) and frequency of power modulation - gating frequency ( f mod ). During the synthesis process, a plasma diagnostic was performed by optical emission spectroscopy (OES). We have observed that the structure of Cu-N layers strongly depends on these parameters. The interpretation of the obtained results of the phase composition was based on OES measurements, focusing mainly on elementary processes in plasma. The duration of target sputtering in each pulse of plasma, controlled by the frequency of power modulation, has been pointed out as the cause of observed differences in the phase composition of the layers. The results of the reported study proved the correct selection of the parameters of Cu 3 N synthesis. Moreover, they showed that the gating frequency can be considered a significant parameter of the magnetron sputtering process affecting the final state of the product of synthesis. [ABSTRACT FROM AUTHOR]

Vortex-induced vibration (VIV) due to periodic vortex shedding around the cylindrical structures is a typical and complicated fluid-structure interaction issue. In this paper, an improved time domain numerical simulation model, which can take the variation effect of added mass into account, is proposed to predict VIV for flexible risers. Originated from forced vibration experimental data, a time-varying function of both response frequency and amplitude is used to describe hydrodynamic forces, and added mass coefficient is considered variable with response frequency. Modal analysis serving VIV hydrodynamic forces calculation is implemented at the beginning of each time step, and dominant frequency of every element will be updated based on real-time structural natural frequency. By validating with model tests of two flexible risers, the proposed model is proved to show better performance for VIV prediction than traditional method (assuming Ca = 1). The added mass variation effect on VIV is discussed qualitatively and quantitatively. [ABSTRACT FROM AUTHOR]

The objective of gating system design and construction process using high pressure die casting is manufacturing of castings with good mechanical and quality properties. The design must take into account various parameters, ranging from the alloy properties through technical parameters of the casting cycle to the construction of the machine and the mould dimensions. If the design of gating system is meant for an existing mould, the runner length depends on the dimensions of the mould. If the design of gating system intends to use a new mould, the runner length depends on the alloy properties, mainly on the melt solidification time when passing the gating system. The article presented deals with the maximum allowed runner length and introduce and defines the term "critical runner length". When designing gating system for a new type of casting, measures were taken using a simulation program, in order to identify the critical runner length, on which the design of mould multiplicity and placement of casting in the mould depend. The critical runner length is defined on the basis of the maximum melt temperature at selected parts of the gating system and the proportion of solid phase in the melt. Based on the measures taken, the temperatures of the melt are described in dependence on time, heat losses are determined in dependence on the runner length and subsequently the maximum allowed runner length is determined. The measurements, the results and conclusions described in the article are further directly implemented in the innovations of die casting in the production. [ABSTRACT FROM AUTHOR]

A laser range-gated viewing experiment in the eye-safe spectral region is demonstrated where a semiconductor based laser illuminator is associated with a corresponding image detector able to operate in high frequency and high sensitivity shutter mode. After experimental validations of the camera developed for accumulation operation, a high power semiconductor based illuminator has been designed and realized. This technology can be used to develop efficient, compact and high average power SWIR illuminators. Images of different scenes were recorded in a test tunnel and the results are compared to those recorded simultaneously with a solid state based laser illuminator working in flash mode. Both results are similar in terms of image intensity whereas semiconductor based recordings exhibits lower speckle noise and better homogeneity. These results open new opportunities for compact and efficient SWIR active imaging systems. [ABSTRACT FROM AUTHOR]

Electrical manipulation of charged ions in electrolyte-gated transistors is crucial for enhancing the electric-double-layer (EDL) gating effect, thereby improving their sensing abilities. Here, indium-zinc-oxide (IZO) based thin-film-transistors (TFTs) are fabricated on flexible plastic substrate. Acid doped chitosan-based biopolymer electrolyte is used as the gate dielectric, exhibiting an extremely high EDL capacitance. By regulating the dynamic EDL charging process with special gate potential profiles, the EDL gating effect of the chitosan-gated TFT is enhanced, and then resulting in higher pH sensitivities. An extremely high sensitivity of ∼57.8 mV/pH close to Nernst limit is achieved when the gate bias of the TFT sensor sweeps at a rate of 10 mV/s. Additionally, an enhanced sensitivity of 2630% in terms of current variation with pH range from 11 to 3 is realized when the device is operated in the ion depletion mode with a negative gate bias of −0.7 V. Robust ionic modulation is demonstrated in such chitosan-gated sensors. Efficiently driving the charged ions in the chitosan-gated IZO-TFT provides a new route for ultrasensitive, low voltage, and low-cost biochemical sensing technologies. [ABSTRACT FROM AUTHOR]

Pouring of liquid aluminium is typically accompanied by disturbance of the free surface. During these disturbances, the free surface oxide films can be entrained in the bulk of liquid, also pockets of air can be accidentally trapped in this oxide films. The resultant scattering of porosity in castings seems nearly always to originate from the pockets of entrained air in oxide films. Latest version of ProCast software allows to identify the amount of oxides formed at the free surface and where they are most likely to end-up in casts. During a filling calculation, ProCast can calculate different indicators which allow to better quantify the filling pattern. The fluid front tracking indicator " Free surface time exposure" has the units [cm2*s]. At each point of the free surface, the free surface area is multiplied by the time. This value is cumulated with the value of the previous timestep. In addition, this value is transported with the free surface and with the fluid flow.Experiments to validate this new functions were executed. [ABSTRACT FROM AUTHOR]

Spider gating modifier toxins (GMTs) are potent modulators of voltage-gated ion channels and have thus attracted attention as drug leads for several pathophysiological conditions. GMTs contain three disulfide bonds organized in an inhibitory cystine knot, which putatively confers them with high stability; however, thus far, there has not been a focused study to establish the stability of GMTs in physiological conditions. We examined the resistance of five GMTs including GpTx-1, HnTx-IV, HwTx-IV, PaurTx-3 and SgTx-1, to pH, thermal and proteolytic degradation. The peptides were stable under physiological conditions, except SgTx-1, which was susceptible to proteolysis, probably due to a longer C-terminus compared to the other peptides. In non-physiological conditions, the five peptides withstood chaotropic degradation, and all but SgTx-1 remained intact after prolonged exposure to high temperature; however, the peptides were degraded in strongly alkaline solutions. GpTx-1 and PaurTx-3 were more resistant to basic hydrolysis than HnTx-IV, HwTx-IV and SgTx-1, probably because a shorter interconnecting loop 3 on GpTx-1 and PaurTx-3 may stabilize interactions between the C-terminus and the hydrophobic patch. Here, we establish that most GMTs are exceptionally stable, and propose that, in the design of GMT-based therapeutics, stability can be enhanced by optimizing the C-terminus in terms of length, and increased interactions with the hydrophobic patch. [ABSTRACT FROM AUTHOR]

We proposed an ultrafast optical gating configuration for ultrafast measuring the characters of a supercontinuum (SC) probe beam. Single femtosecond laser beam pumped transient diffraction (TrD) and transient lens (TrL) effects were realized at the same time, which ensured the measurement in background-free geometry. Experimental results showed that the proposed ultrafast optical gating was robust for very high signal-to-noise ratio (SNR) detecting. [ABSTRACT FROM AUTHOR]

The demand for contactless and wear-free sensor systems for the measurement of different physical values, such as angle, position, or speed has increased over the past years and opened up new application areas for magnetically sensitive sensors. Polymer bonded magnets can be used as signal transmitters in these sensor applications. In general, a high precision and good repeatability of the magnetic field is required, whereas in particular, a high peak flux density and accurate pole length of each pole is demanded for precise measurement. These polymer bonded magnets can be produced economically using the injection molding process with an integrated magnetization of the particles, such that a second magnetization step is unnecessary. This article addresses the influences of the gating system on the magnetic properties of multipolar bonded rings. Further, the particle orientation as well as filler content at different locations, and along the pathway are investigated. It was evaluated that the gating system significantly influences the pole length accuracy, as well as the peak flux density. However, differences in the filler orientation and content cannot be analyzed quantitatively. [ABSTRACT FROM AUTHOR]

This paper presents a silicon-proven fault tolerant FPGA architecture that can repair a wide range of hardware faults. The proposed architecture does not require fine-grained fault location, and the error map is stored in non-volatile resistive memory that is monolithically integrated on top of the CMOS circuit. Redundancy operations are fully self-contained and do not affect data streaming in and out of the FPGA. The power gating scheme is implemented to save idle leakage power and fix hardware faults in the power network. Significant yield enhancement is expected using this architecture. The architecture has been verified in a test chip fabricated in 28nm technology. Redundancy operation is solely controlled by on chip fault locators which are HfO2-based resistive memories monolithically integrated after CMOS process. The maximum shift in performance is about 2 percent when the redundancy is engaged, and the power footprint is unaffected. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study is to propose and validate an alarm gating system for a myocardial ischemia monitoring system that uses ambulatory electrocardiogram. The PeriOperative ISchemic Evaluation study recommended the selective administration of β blockers to patients at risk of cardiac events following noncardiac surgery. Patients at risk are identified by monitoring ST segment deviations in the electrocardiogram (ECG); however, patients are encouraged to ambulate to improve recovery, which deteriorates the signal quality of the ECG leading to false alarms. Methods: The proposed alarm gating system computes a signal quality index (SQI) to quantify the ECG signal quality and rejects alarms with a low SQI. The system was validated by artificially contaminating ECG records with motion artifact records obtained from the long-term ST database and MIT-BIH noise stress test database, respectively. Results: Without alarm gating, the myocardial ischemia monitoring system attained a Precision of 0.31 and a Recall of 0.78. The alarm gating improved the Precision to 0.58 with a reduction of Recall to 0.77. Conclusion: The proposed system successfully gated false alarms with future work exploring the misidentification of fiducial points by myocardial ischemia monitoring systems. Significance: The reduction of false alarms due to the proposed system will decrease the incidence of the alarm fatigue condition typically found in clinicians. Alarm fatigue condition was rated as the top patient safety hazard from 2012 to 2015 by the Emergency Care Research Institute. [ABSTRACT FROM AUTHOR]

Voltage-gated ion channels couple transmembrane potential changes to ion flow. Conformational changes in the voltage-sensing domain (VSD) of the channel are thought to be transmitted to the pore domain (PD) through an α-helical linker between them (S4-S5 linker). However, our recent work on channels disrupted in the S4-S5 linker has challenged this interpretation for the KCNH family. Furthermore, a recent single-particle cryo-electron microscopy structure of KV10.1 revealed that the S4-S5 linker is a short loop in this KCNH family member, confirming the need for an alternative gating model. Here we use "split" channels made by expression of VSD and PD as separate fragments to investigate the mechanism of gating in KV10.1. We find that disruption of the covalent connection within the S4 helix compromises the ability of channels to close at negative voltage, whereas disconnecting the S4-S5 linker from S5 slows down activation and deactivation kinetics. Surprisingly, voltage-clamp fluorometry and MTS accessibility assays show that the motion of the S4 voltage sensor is virtually unaffected when VSD and PD are not covalently bound. Finally, experiments using constitutively open PD mutants suggest that the presence of the VSD is structurally important for the conducting conformation of the pore. Collectively, our observations offer partial support to the gating model that assumes that an inward motion of the C-terminal S4 helix, rather than the S4-S5 linker, closes the channel gate, while also suggesting that control of the pore by the voltage sensor involves more than one mechanism. [ABSTRACT FROM AUTHOR]

Casting defects that are closely related to entrapped air bubbles and metallic oxides occur very frequently in the sand mold casting process. Many researchers have shown that these defects can be reduced by adopting an appropriate gating system design. However, it is difficult for field engineers to identify a specific gating system that is more appropriate for their products. In this study, we tried to draw a comparison between two gating system designs with and without a ceramic foam filter. The ceramic foam filter was added to the horizontal runner just after the down sprue to prevent air bubble generation and reduce turbulence without a change of gating system design. The water modeling experiment was conducted with four different amounts of the initial volumes of water in the reservoir to verify the effects of initial pouring velocity. The results of the experiment applying the filter showed remarkably changed flow characteristics. The use of the filter was found to convert the flow pattern of water in the desired direction. The ceramic foam filter performed well to reduce flow velocity and stabilize the water stream.The flow pattern without a filter can be improved significantly even with the the use of just a 10 PPI irregular filter. Although the study confirmed that use of the filter may change the flow characteristics, it needs to be noted that the use of the ceramic filter alone cannot solve all the problems caused by a poorly designed gating system. [ABSTRACT FROM AUTHOR]

All-printed transistors consisting of interconnected networks of various types of two dimensional nanosheets are an important goal in nanoscience. Using electrolytic gating, we demonstrate all-printed, vertically stacked transistors with graphene source, drain, and gateelectrodes, a transition metal dichalcogenide channel, and a boron nitride (BN) separator, all formed from nanosheet networks. The BN network contains an ionic liquid within its porous interior that allows electrolytic gating in a solid-like structure. Nanosheet network channelsdisplay on:off ratios of up to 600, transconductances exceeding 5 millisiemens, and mobilities of >0.1 square centimeters per volt per second. Unusually, the on-currents scaled with networkthickness and volumetric capacitance. In contrast to other devices with comparable mobility, large capacitances, while hindering switching speeds, allow these devices to carry higher currents at relatively low drive voltages. [ABSTRACT FROM AUTHOR]

The paper presents a methodology of optimization of the gating system for sand casting using the genetic algorithm. Software package for computer-aided design/computer-aided manufacturing (CAD/CAM) was used as the support to the design and verification of the optimized gating system. The geometry of the gating system of sand casting in excavator tooth holder was the subject of optimization. The objective was to maximize filling rate given the constraints posed by both the ingate module and Reynolds number. Mold filling time has been presented as a function of the ingate cross section and casting height. Given the conditions above, as the result of the optimization, a complete geometry of the gating system has been defined. Numerical simulation (software MAGMA) has been used to verify the validity of the optimized geometry of the gating system. [ABSTRACT FROM AUTHOR]

In this article, a method was investigated for elimination of the oxide layers and sand inclusion which have been created by turbulence in a kind of pressure plate part of the gray cast iron that is used in automotive industries. The pressure plate was produced by green sand Disamatic vertical molding line in a four cavities mold. In primary design of the gating system, the parts included some defects after production. After reviewing by optic microscopes and scanning electron microscope equipped to energy dispersive X-ray spectroscopy, it was realized that these defects are double oxide layers. The simulation results showed that the melt velocity was more than critical velocity just before entering into the cavity in the pressurized gating system (PGS). This agent was related to several factors such as size and thickness of the gate, choke position and type of connection ingate to the part at its model. This can lead to create double oxide layers. Reynolds number ( Re) was used to show the turbulence or the non-turbulence of the fluid. Thus, a new version gating system (NVGS) was designed to decrease the melt velocity by changing the design of the pouring cup, vertical and horizontal runners, wells, chokes and ingates. The NVGS design was evaluated by the simulation software and compared with PGS design. The results showed that the melt in the ingate at the NVGS was smooth and non-turbulence. In addition, the Re was less than its critical value. Accordingly, parts produced by NVGS design were produced without any oxide layers and sand inclusion defect and final inspections were confirmed. [ABSTRACT FROM AUTHOR]