Outer Modulation Research Articles

The effect of reduced training in neural architecture search

As neural architecture search becomes an increasingly studied field, it has become apparent that it demands a great number of computational resources. These are usually devoted to computations and utilized to train and evaluate intermediate solutions during the search phase. Although most researchers focus on developing more efficient search methods, the main computational cost in terms of execution time percentage concerns the evaluation of candidate architectures. As such, many works utilize a smaller number of training epochs during search phase evaluations. In this work, we study the effect of reduced training in neural architecture search. We focus on the retention of relative rankings between architectures when they are trained with different optimizers and for various epochs. We discover relatively high rank correlations between various fully and partially trained, arbitrarily connected architectures (Kendall’s tau-b > 0.7). These are generated by mutating a simple convolutional architecture for the CIFAR-10 image recognition dataset. Furthermore, we observe similar behaviors in networks sampled from the NASBench neural architecture dataset, consisting of a fixed outer skeleton and variable cell module composition. Finally, we demonstrate the ability of genetic algorithms to find optimal solutions in noisy environments, by simulating the previous findings with perturbed n-dimensional Rastrigin functions.

Robust Estimation of Absolute Camera Pose via Intersection Constraint and Flow Consensus.

Estimating the absolute camera pose requires 3D-to-2D correspondences of points and/or lines. However, in practice, these correspondences are inevitably corrupted by outliers, which affects the pose estimation. Existing outlier removal strategies for robust pose estimation have some limitations. They are only applicable to points, rely on prior pose information, or fail to handle high outlier ratios. By contrast, we propose a general and accurate outlier removal strategy. It can be integrated with various existing pose estimation methods originally vulnerable to outliers, and is applicable to points, lines, and the combination of both. Moreover, it does not rely on any prior pose information. Our strategy has a nested structure composed of the outer and inner modules. First, our outer module leverages our intersection constraint, i.e., the projection rays or planes defined by inliers intersect at the camera center. Our outer module alternately computes the inlier probabilities of correspondences and estimates the camera pose. It can run reliably and efficiently under high outlier ratios. Second, our inner module exploits our flow consensus. The 2D displacement vectors or 3D directed arcs generated by inliers exhibit a common directional regularity, i.e., follow a dominant trend of flow. Our inner module refines the inlier probabilities obtained at each iteration of our outer module. This refinement improves the accuracy and facilitates the convergence of our outer module. Experiments on both synthetic data and real-world images have shown that our method outperforms state-of-the-art approaches in terms of accuracy and robustness.

Structure of the inner kinetochore CCAN complex assembled onto a centromeric nucleosome.

In eukaryotes, accurate chromosome segregation in mitosis and meiosis maintains genome stability and prevents aneuploidy. Kinetochores are large protein complexes, that by assembling onto specialized Cenp-A nucleosomes 1,2, function to connect centromeric chromatin to microtubules of the mitotic spindle 3,4. Whereas the centromeres of vertebrate chromosomes comprise Mb of DNA and attach to multiple microtubules, the simple point centromeres of budding yeast are connected to individual microtubules 5,6. All 16 budding yeast chromosomes assemble complete kinetochores using a single Cenp-A nucleosome (Cenp-ANuc), each of which is perfectly centred on its cognate centromere 7–9. The inner and outer kinetochore modules are responsible for interacting with centromeric chromatin and microtubules, respectively. Here, we describe the cryo-EM structure of the S. cerevisiae inner kinetochore module - the constitutive centromere associated network (CCAN) complex, assembled onto a Cenp-A nucleosome (CCAN–Cenp-ANuc). The structure explains the inter-dependency of CCAN’s constituent sub-complexes and shows how the ‘Y’-shaped opening of CCAN accommodates Cenp-ANuc to allow specific CCAN subunits to contact the nucleosomal DNA and histone subunits. Interactions with the unwrapped DNA duplex at the two termini of Cenp-ANuc are mediated predominantly by a DNA-binding groove present in the Cenp-LN sub-complex. Disruption of these interactions impairs assembly of CCAN onto Cenp-ANuc. Our data indicate a mechanism of Cenp-A nucleosome recognition by CCAN and how CCAN acts as a platform for assembly of the outer kinetochore for linking centromeres to the mitotic spindle for chromosome segregation.

Metal Reduction and Protein Secretion Genes Required for Iodate Reduction by Shewanella oneidensis

The metal-reducing gammaproteobacterium Shewanella oneidensis reduces iodate (IO3 -) as an anaerobic terminal electron acceptor. Microbial IO3 - electron transport pathways are postulated to terminate with nitrate (NO3 -) reductase, which reduces IO3 - as an alternative electron acceptor. Recent studies with S. oneidensis, however, have demonstrated that NO3 - reductase is not involved in IO3 - reduction. The main objective of the present study was to determine the metal reduction and protein secretion genes required for IO3 - reduction by Shewanella oneidensis with lactate, formate, or H2 as the electron donor. With all electron donors, the type I and type V protein secretion mutants retained wild-type IO3 - reduction activity, while the type II protein secretion mutant lacking the outer membrane secretin GspD was impaired in IO3 - reduction. Deletion mutants lacking the cyclic AMP receptor protein (CRP), cytochrome maturation permease CcmB, and inner membrane-tethered c-type cytochrome CymA were impaired in IO3 - reduction with all electron donors, while deletion mutants lacking c-type cytochrome MtrA and outer membrane β-barrel protein MtrB of the outer membrane MtrAB module were impaired in IO3 - reduction with only lactate as an electron donor. With all electron donors, mutants lacking the c-type cytochromes OmcA and MtrC of the metal-reducing extracellular electron conduit MtrCAB retained wild-type IO3 - reduction activity. These findings indicate that IO3 - reduction by S. oneidensis involves electron donor-dependent metal reduction and protein secretion pathway components, including the outer membrane MtrAB module and type II protein secretion of an unidentified IO3 - reductase to the S. oneidensis outer membrane.IMPORTANCE Microbial iodate (IO3 -) reduction is a major component in the biogeochemical cycling of iodine and the bioremediation of iodine-contaminated environments; however, the molecular mechanism of microbial IO3 - reduction is poorly understood. Results of the present study indicate that outer membrane (type II) protein secretion and metal reduction genes encoding the outer membrane MtrAB module of the extracellular electron conduit MtrCAB are required for IO3 - reduction by S. oneidensis On the other hand, the metal-reducing c-type cytochrome MtrC of the extracellular electron conduit is not required for IO3 - reduction by S. oneidensis These findings indicate that the IO3 - electron transport pathway terminates with an as yet unidentified IO3 - reductase that associates with the outer membrane MtrAB module to deliver electrons extracellularly to IO3.

Подавление турбулентности в течениях с вращением

The possibilities of turbulence control in spherical Couette flow were examined experimentally. It was shown, that with increasing of outer sphere rotational rate modulation amplitude, the suppression of turbulence is possible with transition to laminar flow state. The reverse process - turbulence recovery - is available with amplitude decreasing. It was established that turbulence breaking and recovering is accompanied by hysteresis. It was shown, that at small values of modulation amplitude, suppression of turbulence is available only in narrow frequency band.

Aggregatibacter actinomycetemcomitans LPS binds human interleukin-8

ABSTRACTVarious gram-negative species sequester host cytokines using outer membrane proteins or surface modulation by sulfated polysaccharides. An outer membrane lipoprotein (BilRI) of the periodontal pathogen Aggregatibacter actinomycetemcomitans binds several cytokines, including interleukin (IL)-8. Because IL-8 is positively charged at physiological pH, we aimed to determine whether IL-8 interacts with negatively charged lipopolysaccharide (LPS). Binding was investigated using electrophoretic mobility shift assays and microwell-based time-resolved fluorometric immunoassay. LPS from each tested strain of A. actinomycetemcomitans (N = 13), Pseudomonas aeruginosa (N = 1) and Escherichia coli (N = 1) bound IL-8. The Kd value of the A. actinomycetemcomitans LPS-IL-8 interaction varied between 1.2–17 μM irrespective of the serotype and the amount of phosphorus in LPS and was significantly lower than that of the BilRI-IL-8 interaction. Moreover, IL-8 interacted with whole A. actinomycetemcomitans cells and outer membrane vesicles. Hence, LPS might be involved in binding of IL-8 to the outer membrane of A. actinomycetemcomitans. This raises an interesting question regarding whether other gram-negative periodontal pathogens use LPS for IL-8 sequestering in vivo.

Robust MSE-Balancing Hierarchical Linear/Tomlinson-Harashima Precoding for Downlink Massive MU-MIMO Systems

In this paper, we propose a robust minimum maximum mean square error Tomlinson-Harashima precoding (Min-Max-MSE THP) scheme and a low-complexity robust Min-Max-MSE hierarchical linear/THP (HL-THP) scheme for downlink massive multiuser multiple-input-multiple-output (MU-MIMO) systems with imperfect channel state information (CSI) at the transmitter. The proposed robust Min-Max-MSE HL-THP scheme comprises an inner linear beamformer (BF), which is designed based on second-order CSI statistics, and outer THP modules, which exploit the instantaneous overall CSI of the cascade of the actual channel and the inner BF. Thereby, the user terminals are divided into groups, where for each group a THP module successively mitigates the intra-group interference, whereas the inter-group interference is canceled by the inner BF. To ensure fairness, we adopt the maximization of the asymptotic signal-to-leakage-plus-noise ratio in the large system limit and the Min-Max-MSE as an optimization criterion for designing the inner BF and the per-group THP modules, respectively. Our analytical and simulation results show that the proposed robust Min-Max-MSE HL-THP scheme achieves a substantially improved performance in terms of the Max-MSE, maximum bit error rate, and minimum rate compared to linear regularized zero-forcing precoding. Moreover, the performance loss of the proposed robust Min-Max-MSE HL-THP scheme compared to the robust Min-Max-MSE THP scheme is small. In addition, our complexity analysis reveals that the proposed robust Min-Max-MSE HL-THP scheme has a much lower computational complexity than the Min-Max-MSE THP scheme. Hence, the robust Min-Max-MSE HL-THP scheme provides a favorable tradeoff between complexity and performance.

A method for determining the allocation strategy of on-shore power supply from a green container terminal perspective

The main contribution of this paper is to determine the allocation strategy of on-shore power supply (OPS), comprising additional power capacity of OPS and adopting patterns of OPS at berth, to realize the trade-off between total cost of OPS and carbon emissions of ships. Firstly, carbon emission formulations, adopting patterns of OPS and arrival patterns of ships are described. Then, in order to minimize total cost and carbon emissions, an integer programming model for OPS allocation problem is proposed. Next, a simulation-based solution method is developed to resolve the optimization model, which consists of inner simulation module and outer optimization module. The outer module enumerates all the allocation scenarios and evaluates the results from the inner module. The inner module introduces a simulation model to represent the stochastic operation system in the container terminal and outputs results to outer module. Finally, taking a port in China as an example, this paper designs and conducts a series of experiments and discovers that the sensitivity of results emphasizes the importance of electricity price on the optimal allocation. When electricity price is lower or larger than 0.3 $/kWh, the optimal power capacity is 9200 or 5230 kW, correspondingly.

Evolution of protein transport to the chloroplast envelope membranes.

Chloroplasts are descendants of an ancient endosymbiotic cyanobacterium that lived inside a eukaryotic cell. They inherited the prokaryotic double membrane envelope from cyanobacteria. This envelope contains prokaryotic protein sorting machineries including a Sec translocase and relatives of the central component of the bacterial outer membrane β-barrel assembly module. As the endosymbiont was integrated with the rest of the cell, the synthesis of most of its proteins shifted from the stroma to the host cytosol. This included nearly all the envelope proteins identified so far. Consequently, the overall biogenesis of the chloroplast envelope must be distinct from cyanobacteria. Envelope proteins initially approach their functional locations from the exterior rather than the interior. In many cases, they have been shown to use components of the general import pathway that also serves the stroma and thylakoids. If the ancient prokaryotic protein sorting machineries are still used for chloroplast envelope proteins, their activities must have been modified or combined with the general import pathway. In this review, we analyze the current knowledge pertaining to chloroplast envelope biogenesis and compare this to bacteria.

Novel U-Shaped Structure Switched Reluctance Machine With a Module Outer Rotor

This paper introduces a novel 16/12 outer module rotor-type switched reluctance machine. Unlike conventional structures, the proposed rotor structure includes some discrete module, and every outer module rotor is U-shaped structure and has two rotor poles. Each phase winding is composed of two series coils wrapped on two stator teeth. The short flux lines can be generated by excited adjacent phase and use the U-shaped module rotor. The module rotor can also decrease the mass of the rotor. The proposed U-shaped structure machine can enhance the electrical utilization, decrease the magneto motive force requirement, and reduce the iron loss compared with the conventional machine. The operation and design principle of the proposed U-shaped structure machine are illustrated and elaborated to verify the machine operation performance. The static and dynamic performance of the proposed U-shaped structure 16/12 outer rotor machine and conventional machine is obtained by the finite-element method. The effectiveness and availability of the proposed U-shaped structure outer rotor machine are confirmed by the simulation results.

The Development of Mid-Wavelength Photoresponsivity in the Mouse Retina

ABSTRACTPurpose: Photoreceptors in the mouse retina express much of the molecular machinery necessary for phototransduction and glutamatergic transmission prior to eye opening at postnatal day 13 (P13). Light responses have been observed collectively from rod and cone photoreceptors via electroretinogram recordings as early as P13 in mouse, and the responses are known to become more robust with maturation, reaching a mature state by P30. Photocurrents from single rod outer segments have been recorded at P12, but no earlier, and similar studies on cone photoreceptors have been done, but only in the adult mouse retina. In this study, we wanted to document the earliest time point in which outer retinal photoreceptors in the mouse retina begin to respond to mid-wavelength light.Methods: Ex-vivo electroretinogram recordings were made from isolated mouse retinae at P7, P8, P9, P10, and P30 at seven different flash energies (561 nm). The a-wave was pharmacologically isolated and measured at each developmental time point across all flash energies.Results: Outer-retinal photoreceptors generated a detectable response to mid-wavelength light as early as P8, but only at photopic flash energies. a-wave intensity response curves and kinetic response properties are similar to the mature retina as early as P10.Conclusion: These data represent the earliest recorded outer retinal light responses in the rodent. Photoreceptors are electrically functional and photoresponsive prior to eye opening, and much earlier than previously thought. Prior to eye opening, critical developmental processes occur that have been thought to be independent of outer retinal photic modulation. However, these data suggest light acting through outer-retinal photoreceptors has the potential to shape these critical developmental processes.

Online Combinatorial Optimization for Interconnected Refrigeration Systems: Linear Approximation and Submodularity

This paper proposes a new control method that can save the energy consumption of multi-case supermarket refrigerators by explicitly taking into account their interconnected and switched system dynamics. Its novelty is a bilevel combinatorial optimization formulation to generate ON/OFF control actions for expansion valves and compressors. The inner optimization module keeps display case temperatures in a desirable range and the outer optimization module minimizes energy consumption. In addition to its energy-saving capability, the proposed controller significantly reduces the frequency of compressor switchings by employing a conservative compressor control strategy. However, solving this bilevel optimization problem associated with interconnected and switched systems is a computationally challenging task. To solve the problem in near real time, we propose two approximation algorithms that can solve both the inner and outer optimization problems at once. The first algorithm uses a linear approximation, and the second is based on the submodular structure of the optimization problem. Both are (polynomial-time) scalable algorithms and generate near-optimal solutions with performance guarantees. Our work complements existing optimization-based control methods (e.g., MPC) for commercial refrigerators, as our algorithms can be adopted as a tool for solving combinatorial optimization problems arising in these methods.

Molecular basis of outer kinetochore assembly on CENP-T.

Stable kinetochore-microtubule attachment is essential for cell division. It requires recruitment of outer kinetochore microtubule binders by centromere proteins C and T (CENP-C and CENP-T). To study the molecular requirements of kinetochore formation, we reconstituted the binding of the MIS12 and NDC80 outer kinetochore subcomplexes to CENP-C and CENP-T. Whereas CENP-C recruits a single MIS12:NDC80 complex, we show here that CENP-T binds one MIS12:NDC80 and two NDC80 complexes upon phosphorylation by the mitotic CDK1:Cyclin B complex at three distinct CENP-T sites. Visualization of reconstituted complexes by electron microscopy supports this model. Binding of CENP-C and CENP-T to MIS12 is competitive, and therefore CENP-C and CENP-T act in parallel to recruit two MIS12 and up to four NDC80 complexes. Our observations provide a molecular explanation for the stoichiometry of kinetochore components and its cell cycle regulation, and highlight how outer kinetochore modules bridge distances of well over 100 nm.

Thermal-hydraulic analysis of the coil test facility for CFETR.

BackgroundPerformance test of the China Fusion Engineering Test Reactor (CFETR) central solenoid (CS) and toroidal field (TF) insert coils is of great importance to evaluate the CFETR magnet performance in relevant operation conditions. The superconducting magnet of the coil test facility for CFETR is being designed with the aim of providing a background magnetic field to test the CFETR CS insert and TF insert coils.ResultsThe superconducting magnet consists of the inner module with Nb3Sn coil and the outer module with NbTi coil. The superconducting magnet is designed to have a maximum magnetic field of 12.59 T and a stored energy of 436.6 MJ. An active quench protection circuit and the positive temperature coefficient dump resistor were adopted to transfer the stored magnetic energy.ConclusionsThe temperature margin behavior of the test facility for CFETR satisfies the design criteria. The quench analysis of the test facility shows that the cable temperature and the helium pressure inside the jacket are within the design criteria.

Electromagnetic Optimization and Preliminary Mechanical Analysis of the CFETR CS Model Coil

The central solenoid model coil of China Fusion Engineering Test Reactor consists of two modules: 1) the inner module made of Nb3Sn and 2) the outer module made of NbTi. This paper describes an optimization procedure for the electromagnetic design of the model coil by means of a Fortran code written for this purpose. The target of the optimization was the reduction of the length of the Nb3Sn cable-in-conduit conductor, needed to produce a peak magnetic field of 12 T. The optimization constraints are: 1) the maximum magnetic field on the NbTi module should be lower than 6 T and 2) the unit length of one Nb3Sn conductor should be shorter than 1 km. Based on the electromagnetic optimization, the engineering scheme of the model coil is determined. The feasibility of the engineering scheme is investigated using ANSYS finite element code. Accordingly, a mechanical analysis of the structure under the Lorentz force at 4.5 K is performed. The analysis results indicate that the present design is reasonable and fulfills the design requirements.

Fully automated macromolecule suppressed single voxel glutamate spectroscopy (FAMOUS SVGS).

PurposeThe aim of the study was to develop and validate a new localized 1H MRS pulse sequence and automated post-processing software for the quantification of brain Glutamate (Glu) in clinical conditions at 7.0T in order to get reliable and reproducible results for acute intervention studies.MethodsHere we describe a new localized proton MRS method “Fully Automated MacrOmolecUle Suppressed Single Voxel Glutamate Spectroscopy (FAMOUS SVGS)” for measuring Glu. FAMOUS SVGS method consists of a new pulse sequence with optimized switchable water, metabolites and outer volume suppression modules, as well as a frequency selective inversion pulse and automated post-processing of the five spectra obtained. FAMOUS SVGS method was first validated with glutamate phantoms and then validated with test–retest repeatability studies in the occipital cortex of five normal volunteers at 7.0T.ResultsGlutamate concentrations estimated from phantoms with FAMOUS SVGS method correlated well with actual concentrations. Test–retest repeatability studies in human brain in vivo yielded less than 0.3 mM intra-subject variations in Glu concentrations.ConclusionsFAMOUS SVGS method enables Glu quantification in vivo at 7.0T with test–retest variability of less than 0.3 mM. We expect that we can reliably measure ≥0.5 mM change in glutamate due to any acute intervention.

A mesh adaptivity scheme on the Landau–de Gennes functional minimization case in 3D, and its driving efficiency

This paper presents a 3D mesh adaptivity strategy on unstructured tetrahedral meshes by a posteriori error estimates based on metrics derived from the Hessian of a solution. The study is made on the case of a nonlinear finite element minimization scheme for the Landau–de Gennes free energy functional of nematic liquid crystals. Newton's iteration for tensor fields is employed with steepest descent method possibly stepping in.Aspects relating the driving of mesh adaptivity within the nonlinear scheme are considered. The algorithmic performance is found to depend on at least two factors: when to trigger each single mesh adaptation, and the precision of the correlated remeshing. Each factor is represented by a parameter, with its values possibly varying for every new mesh adaptation. We empirically show that the time of the overall algorithm convergence can vary considerably when different sequences of parameters are used, thus posing a question about optimality.The extensive testings and debugging done within this work on the simulation of systems of nematic colloids substantially contributed to the upgrade of an open source finite element-oriented programming language to its 3D meshing possibilities, as also to an outer 3D remeshing module.

Performance evaluation of hollow fiber air gap membrane distillation module with multiple cooling channels

The hollow fiber air gap membrane distillation (AGMD) module equipped with the multiple cooling channels network made of stainless steel was developed. The performance of the developed AGMD module was evaluated by conducting several experiments, including the effect of feed temperature and flow rate, ratio of membrane surface area to condensation surface area, membrane packing position, comparison with hollow fiber DCMD, and the effect of inner and outer module channels to process performance. Moreover, theoretical model was suggested for the multiple cooling channels module. This study reveals that the produced flux and thermal efficiency of this module were up to 12.5kg/m2h and 81.7%, respectively, which is higher than most of previous studies that used polymeric fibers as coolant channels. Furthermore, the optimum ratio of membrane area to condensation surface area to produce optimum flux and thermal efficiency is known to be around 0.55. Further experimental results show that the outer channel has significant contribution in reducing the amount of heat loss. This is also could be the reason why the average flux of hollow fiber AGMD module was only 22% lower, while the average thermal efficiency is 58% higher than that of hollow fiber DCMD module.

Evaluation of Sensor-less Identification Method for Stable Spindle Rotation against Chatter with Milling Simulation Analysis

Although chatter stability analysis is necessary to enhance cutting accuracy and efficiency, a reliable prediction is difficult to achieve because of the analysis error of frequency response function. Therefore, the investigation proposes an experiment-based identification method for stable spindle rotations in milling by gradually changing the spindle rotation and capturing chatter frequency shift from servo information. In order to evaluate the identification accuracy, this paper presents theoretical approaches to analyze time-dependent variation in chatter and the expected identification error of proposed method by using a time-domain simulator and a frequency-domain model considering amplitude ratio between inner and outer modulations of the chip.

Dual Delivery of EPO and BMP2 from a Novel Modular Poly-ɛ-Caprolactone Construct to Increase the Bone Formation in Prefabricated Bone Flaps.

Poly-ɛ-caprolactone (PCL) is a biocompatible polymer that has mechanical properties suitable for bone tissue engineering; however, it must be integrated with biologics to stimulate bone formation. Bone morphogenetic protein-2 (BMP2) delivered from PCL produces bone when implanted subcutaneously, and erythropoietin (EPO) works synergistically with BMP2. In this study, EPO and BMP2 are adsorbed separately on two 3D-printed PCL scaffold modules that are assembled for codelivery on a single scaffold structure. This assembled modular PCL scaffold with dual BMP2 and EPO delivery was shown to increase bone growth in an ectopic location when compared with BMP2 delivery along a replicate scaffold structure. EPO (200 IU/mL) and BMP2 (65 μg/mL) were adsorbed onto the outer and inner portions of a modular scaffold, respectively. Protein binding and release studies were first quantified. Subsequently, EPO+BMP2 and BMP2 scaffolds were implanted subcutaneously in mice for 4 and 8 weeks, and the regenerated bone was analyzed with microcomputed tomography and histology; 8.6±1.4 μg BMP2 (22%) and 140±29 IU EPO (69.8%) bound to the scaffold and <1% BMP2 and 83% EPO was released in 7 days. Increased endothelial cell proliferation on EPO-adsorbed PCL discs indicated protein bioactivity. At 4 and 8 weeks, dual BMP2 and EPO delivery regenerated more bone (5.1±1.1 and 5.5±1.6 mm(3)) than BMP2 alone (3.8±1.1 and 4.3±1.7 mm(3)). BMP2 and EPO scaffolds had more ingrowth (1.4%±0.6%) in the outer module when compared with BMP2 (0.8%±0.3%) at 4 weeks. Dual delivery produced more dense cellular marrow, while BMP2 had more fatty marrow. Dual EPO and BMP2 delivery is a potential method to regenerate bone faster for prefabricated flaps.