Cross Point Research Articles

Tightly focused light field with controllable pure transverse polarization state at the focus.

We report on a facile and flexible scheme for producing the controllable pure transverse polarization state at the focus within a tightly focused field. Toward this aim, a special type of hybrid vector beam exhibiting unusual "8-type" mapping tracks of azimuthal polarization states on the Poincaré sphere is employed. Due to the peculiar polarization structures, at the focus, there is only the transverse component, while the longitudinal component is zero for any 8-type vector beam. More strikingly, the transverse polarization state at the focus is exactly the same as that of the cross point of the 8-type mapping track. Benefiting from this appealing polarization relationship, an arbitrary transverse polarization state can be easily achieved at the focus via altering the mapping track of incident vector beams. These results may have potential applications in nano and spin photonics.

Hierarchical Structured Polyimide-Silica Hybrid Nano/Microfiber Filters Welded by Solvent Vapor for Air Filtration.

Electrospun polymer membranes were considered to be promising materials for fine particulate matter (PM) filtration. However, the poor mechanical properties of the electrospun membrane restricted their application for pressure-driven air filtration. Herein, strength-enhanced electrospun polyimide (PI) membranes were demonstrated via a synergistic approach. Solvent-vapor treatment was utilized to introduce extra bonding at the cross points of PI nanofiber, while SiO2 nanoparticles (SiO2 NPs) were used to reinforce the body of nanofibers. The mechanical strength and filtration performance of hybrid membranes could be regulated by adjusting the quantity of SiO2 NPs. The tensile strength of the pure PI membrane was increased by 33% via adding 1.5% SiO2 NPs, which was further promoted by 70% after solvent-vapor treatment. With a slight reduction in pressure drop (6.5%), the filtration efficiency was not greatly suppressed by welding the SiO2 NP hybrid PI nanofibers. Moreover, the welded composite filter showed high particulate (0.3–1.0 μm) filtration efficiency (up to nearly 100%) and stable pressure drop throughout the 20 tested filtration cycles.

A Track Correlation Algorithm Based on New Space-time Cross-point Feature

To solve the problem of track correlation in practical engineering effectively, a new concept of generalized space-time cross point of track pair is defined in this paper. Then a new algorithm which utilize space-time cross-point as feature points and realizes the track correlation through feature point matching is proposed in this paper. The test experiments with measured data illustrate the proposed algorithm of which the performance is effective, stable and robust, can eliminate redundant tracks and provide a unified situation.

Topological Distillation by Principal Component Analysis in Disordered Fractional Quantum Hall States* *Supported by the National Natural Science Foundation of China (Grant No. 11674282), and the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB28000000).

We study the behavior of two-dimensional electron gas in the fractional quantum Hall (FQH) regime in the presence of disorder potential. The principal component analysis is applied to a set of disordered Laughlin ground state model wave function to enable us to distill the model wave function of the pure Laughlin state. With increasing the disorder strength, the ground state wave function is expected to deviate from the Laughlin state and eventually leave the FQH phase. We investigate the phase transition from the Laughlin state to a topologically trivial state by analyzing the overlap between the random sample wave functions and the distilled ground state wave function. It is proposed that the cross point of the principal component amplitude and its counterpart is the critical disorder strength, which marks the collapse of the FQH regime.

Crushing behavior of honeycomb vs. foam under combined shear-compression loading

This paper conducts a combined compression-shear test on honeycombs and Kelvin foams to compare their yield envelopes. The honeycomb and foam specimens with a similar relative density are fabricated by using the additive manufacturing technique. The quasi-static and dynamic crushing behaviors under combined shear-compression are investigated by employing a universal testing machine and a rotatable Hopkinson bar system, respectively. Five loading angles ranging from 0° to 50° are considered. Results reveal that the normal strengths of both honeycomb and Kelvin foam decrease while the shear strengths increase with the loading angle increasing. Moreover, honeycombs change the deformation mode from the progressive folding mode to the global rotation mode while Kelvin foams maintain the layered folding mode as the loading angle increases. Therefore, honeycombs show the normal strength decreasing more sharply than Kelvin foams. As a result, although honeycombs possess higher normal strengths than Kelvin foams under pure compression, the difference becomes smaller with the increase of loading angle. There is a cross point on the macroscopic yield envelopes of honeycomb and Kelvin foam. At this point, honeycomb and Kelvin foam possess the same normal and shear strengths. Moreover, the dynamic yield envelopes of both honeycombs and Kelvin foams possess an almost isotropic expansion of quasi-static envelopes due to the loading rate effect. These yield envelopes provide design criteria for cellular materials to withstand any applied shear and compressive stress state.

Theoretical distributions of point-defect concentration in a Si ingot grown inside a melt using the noncontact crucible method considering the accumulation effect of diffusion flux

The noncontact crucible (NOC) method has a large and deep low-temperature region in the upper central part of a Si melt to grow a uniform large Si single ingot without contact with the crucible wall. The temperature distribution in the NOC ingot is quite different to that in an ingot grown by the Czochralski (CZ) method because the NOC ingot is grown inside the Si melt. However, the distributions of point defects such as vacancy and interstitial Si atom are not known for the NOC ingot. To clarify the distributions of point defects, a simulation model is proposed to calculate the distribution of point defects in the NOC ingot. The effect of accumulation of diffusion fluxes on the concentrations of both vacancy and interstitial Si atom is considered for NOC growth because these diffusion fluxes are expected to continuously affect such concentrations in the ingot grown with the moving interface under the relatively low temperature gradient inside the melt. This point is one of the large merits of NOC growth. The concentrations of vacancy and interstitial Si atom were also calculated after the dynamic equilibrium pair-annihilation process between the diffused point defects during growth. They were calculated as a function of distance from the growing interface. By selecting the growth conditions, the concentrations of vacancy and interstitial Si atom were found to be very close to each other all over the ingot. The cross point where the concentrations of vacancy and interstitial Si atom were the same was found to strongly depend on G, the temperature gradient in the crystal.

Distinctly Diverse PLQY and Inverse Solid‐State Luminescent Properties in Structure‐Similar Diphenyl Sulfone TADF Molecules: A Role of C─C

AbstractThermally activated delayed fluorescence (TADF) materials can greatly increase internal quantum efficiencies (IQEs) of organic light‐emitting diodes (OLEDs) beyond the spin statistical bottleneck of 25%. However, the mechanisms behind TADF and solid‐state luminescence are not clear. Recently, two diphenyl sulfone TADF molecules with quite similar structures, A1‐D1 and A2‐D1, have been observed to demonstrate distinctly diverse photoluminescence quantum yield (PLQY) and inverse solid‐state luminescent properties. In order to understand the origin of this phenomenon, the TADF mechanism of both molecules is studied using density function theory. The results show that strong spin–orbit coupling, low minimum energy cross point, dense triplet energy level distribution, and a mediate locally excited triplet state (3LE) can facilitate the rapidly reverse intersystem crossing (RISC) process in A1‐D1. Moreover, the solid states of both molecules are characterized via the combined quantum mechanics and molecular mechanics (QM/MM) method. It is attributed to the compact intermolecular stacking; the nonradiative consumption of A2‐D1 is suppressed substantially by the restricted intermolecular rotation (RIR) effect. Therefore, A2‐D1 with low PLQY can exhibit an aggregation‐induced emission (AIE) phenomenon in neat films. This work may benefit the rational design of nondoped OLEDs.

Mechanistic study of Selectfluor-mediated digold-catalyzed Csp3-Csp2 coupling reaction

To obtain preliminary information regarding the number of metal centers involved in redox transformations and address the role of metal centers in the redox steps, we initiated a detailed theoretical study of digold-catalyzed cross-coupling reaction. There would be a cross point of the free energy profiles for bimetallic and monometallic pathways, suggesting that the metal number involving in redox is alterable. Initially, oxidative addition of gold catalyst by Selectfluor takes place via bimetallic manner giving an [AuII aAuII b] complex, which then undergoes disproportionation to afford the mixed-valent [AuI aAuIII b] complex, followed by monometallic reduction.

Three-dimensional analysis of lateral cortical hinge in medial open-wedge high tibial osteotomy: A computational simulation study of adult cadavers.

The objective of this study was to improve the three-dimensional (3D) understanding of optimal lateral cortical hinge in medial open-wedge high tibial osteotomy (MOWHTO) via a computational cadaveric simulation of actual size. The computed tomography data of 117 adult cadavers were imported into Mimics® software to design 3D models of tibia and fibula. To simulate the MOWTHO, a virtual cutting plane was developed inside the safe zone based on established landmarks. After splitting and distracting through the cutting plane, the 10-mm cylinder (Ø 30 mm; height 10 mm) was placed vertically to be occupied properly in the nonosteotomized lateral cortex. The cross points between the round cylinder and cutting plane represented the anterior and posterior hinge points, which were used to validate the 3D position and direction of cortical hinge. A 10-mm cylinder did not violate the proximal tibiofibular joint (PTFJ) and the protruding segment of the condylar area was less than 2 mm in 115 models. The connecting line between anterior and posterior hinge points was an average of 12.1° (range 0-24.1°, SD 4.64) to the lateral side. In the nonoverlapping anteroposterior projection between proximal fibula and tibia, the posterior hinge point was laid over the PTFJ as close as possible. Based on free 360° rotation and magnification without any tilt, no posterior cortical disruption of PTFJ was observed while securing a minimum width of 10 mm. If the posterior hinge point was placed immediately above the PTFJ without involvement, the nonosteotomized portion carried sufficient width greater than 10 mm, despite lateral rotation at an average hinge direction of 12.1°.

A Novel Three-Dimensional High Density Vertical Rram Arrays with Reduced Leakage Current

NAND flash is the most widely used non-volatile memories due to its low cost and rewritable properties. However, some problems exist in NAND flash that need to be solved, such as low writing and reading speed, high operating voltage, and relatively large cell dimensions. Next generation memories, especially resistive random access memory (RRAM) could improve these problems. The technologies of 3D vertical architecture have made a major breakthrough in establishing high-density memory structures. Combined with an array structure, a 3D high density vertical resistive random access memory (VRRAM) cross-point arrays are able to efficiently increase the device density in vertical direction.In this work, a novel 3D VRRAM arrays which contains two VRRAM cells (Pt/ ZnO/ Al and Pt/ ZnO/ Ti) and one normal layered RRAM (Al/ Al2O3/ Ti) at each cross point were constructed. The Al2O3 based device could operate under a lower compliance current, where contained higher resistance than ZnO based cells. With the controlling of compliance current, the leakage current between VRRAM cells and Al/ Al2O3/ Ti cell could be effectively reduced, therefore, the neighboring cells could be operated independently. We demonstrated the introducing of VRRAM structure could achieve high density advantage in vertical direction, and the adjacent cells in 3D vertical structure could be operated independently with scarcely leakage current. The shrinkage of leakage current enhance the stability of devices and increase the feasibility of high density VRRAM structure applications. Figure 1

Evolution of Phase-Change Memory for the Storage-Class Memory and Beyond

In this article, the development history and the technical hurdles of phase-change memory (PCM) are reviewed and recent progress and future directions are discussed. Prospects of PCM for storage-class memory (SCM) are discussed in terms of the technical challenges to satisfy the market requirements, mainly for the performance and cost effectiveness. For a more in-depth discussion, PCM is segmented into the memory part, the access device part, and the sensing scheme part. In the memory part, Set (crystallization)–Reset (amorphization) write characteristics and thermal disturbance (TDB) will be reinterpreted in terms of power consumption and performance of SCM. In the access device part, the application history of various devices, such as the transistor, the diode, and the two-terminal selector, will be reviewed and explained based on the process integration issues and area efficiency. In the next part, various sensing schemes used to make a lower read latency, multilevel cell (MLC), and cross point (X-point) are summarized. Thereafter, future directions and possible evolution pathways of 3-D structures, including X-point and vertical X-point (VXP), will be discussed for the first time. Finally, the feasibility of PCM for neuromorphic application will be followed.

Cervical Fascia Anatomy for Lateral Neck Dissection

Objective: Fascial organization of the neck is quite sophisticated. Fascial layers separate fundamental structures in the neck, and in this way, they build anatomical walls against the spread of malignant lesions. However, metastatic lymph node around the margin of cervical fasciae has a relatively higher incidence of residual disease and local recurrence after surgery. The video aims to demonstrate the strategy of cervical fascia anatomy for lateral neck dissection. Methods: The cervical fascia anatomy is to perform the operation regarding the anatomy of the fascia and biological behavior of tumors. The concept of this procedure is to dissect along the plane of the cervical fasciae in a particular order, which will preserve the functional structures maximally as well as minimize the recurrence of the diseases.1–4 In this video, the concept of cervical fascia anatomy is illustrated through the procedure of lateral neck dissection. Results: There are three typical cervical fasciae in the lateral neck: the investing fascia, the visceral fascia, and the prevertebral fascia. These three hotspots are described as follows: (1) the intermuscular hotspot area located between the sternocleidomastoid and the strap muscles, and here is the attachment of the investing fascia and the visceral fascia. (2) The level II hotspot is in the cross of the internal jugular vein and the accessory nerve, and this is the cross point of all three fasciae. (3) The vertebral artery triangle hotspot is in the crossing of visceral fascia and the pervertible fascia. The procedure of cervical fascia anatomy in lateral neck dissection was as follows: (1) preprocessing the external jugular vein and nerves at level V, (2) separate two layers of investing fasciae enveloped in the sternocleidomastoid muscle, (3) dissect the intermuscular lymph node between the sternocleidomastoid and strap muscles, (4) isolate the vessels in the carotid triangle on the surface of visceral fascia, (5) anatomize the accessory nerve to resect lymph nodes around the nerve, (6) expose the cervical plexus and continue the lateral dissection along the plane of the prevertebral fascia, (7) separate venous corner and anatomize the vertebral triangle, and (8) transfer the specimen to level V and completed the lateral compartment with an entire resection. Conclusion: The concept of cervical fascia anatomy provided an ideal strategy for lateral neck dissection, which will make better protection of the cervical nerve in the lateral compartment. This strategy focuses on dealing of the margin area of cervical fasciae, which will further reduce the residual disease and local recurrence. Authors' Contributions: B.W. (Bo Wang) is the chief surgeon of this operation and provides the original idea of this article, B.W. (Bo Wang), YJ.W., J.Z., YF.Z., and S.L. prepared the article of narration. WX.Z. made a critical revision of this video, SY.Y. was the assistant of this surgery, and B.W. (Brandon Wang) is the English name of Bo Wang. Acknowledgments: Many thanks for the friendship of Professor Gregory Randolph, Dipti Kamani, Ayaka Iwata, and Okenwa Okose in Massachusetts Eye and Ear Infirmary. No competing financial interests exist. Funding Information: This research was supported by the joint funds for the innovation of science and technology, Fujian province (Grant Nos.: 2018Y9093, 2018Y0915, and 2018Y9018); The Health Research Talents Training Project of Fujian Provincial (Grant Nos.: 2019-CX-16 and 2018-CX-17); and the Guiding Social Development Project of Fujian Province (Grant No. 2018Y0035). Additional supporting information may be found in the online version of this article. Runtime of video: 9 mins 32 secs

Mixed-Dimensional Vertical Point p-n Junctions.

Mixed-dimensional van der Waals (vdW) heterostructures composed of one-dimensional (1D) and two-dimensional (2D) materials have exhibited great potential in nanoelectronics and nano-optoelectronics. In this study, we present a vertical point p-n junction (VPpnJ), in which a vertical stacked molybdenum disulfide/tungsten diselenidep-n junction is sandwiched between two cross-stacked metallic carbon nanotubes (CNTs). The device can be transformed from p-n junction to n-n junction via gate modulation. As a photodetector, the VPpnJ device can work in three different modes by setting the appropriate gating voltages. The photosensitive areas are localized around the topCNT, bottom CNT, and the cross point at VG = -10 V, 10 V, and ∼0 V, respectively. In the p-n regime at the negative gate voltage, the VPpnJ device showed an obvious photovoltaic effect. The external quantum efficiency of the VPpnJ can reach 42.7%. The electrical control of the electronic and optoelectronic characteristics can be mainly attributed to the gate-tunable interfacial built-in electric fields in the heterostructures. The progress also reveals the functional diversity of such 1D/2D mixed-dimensional heterostructures, which will be prospects for future nanoelectronics and nano-optoelectronics.

Finite-interval quadratic polynomial inequalities and their application to time-delay systems

This paper proposes two inequality lemmas for the stability analysis of time-delay systems to obtain the stability criteria in terms of linear matrix inequalities from ones in terms of the convex of concave finite-interval quadratic polynomials. The first lemma improves the existing work for the concave finite-interval quadratic polynomial by utilizing the property of a cross point between two tangent lines at the boundaries of the finite interval. The second lemma introduces an inequality for the convex or concave finite-interval quadratic polynomials by decomposing the finite-interval quadratic polynomials into aTMa, where M is a 2 × 2 block matrix and a is a vector consisting of a constant and a variable, and by exploiting information on the finite interval. To illustrate the potential of the proposed lemmas, this paper presents feasible regions for the finite-interval quadratic polynomials and maximum time-delay upper bounds for time-delay systems, comparing to those in the literature.

Novel Segmented Concentration Addition Method to Predict Mixture Hormesis of Chlortetracycline Hydrochloride and Oxytetracycline Hydrochloride to Aliivibrio fischeri.

Hormesis is a concentration-response phenomenon characterized by low-concentration stimulation and high-concentration inhibition, which typically has a nonmonotonic J-shaped concentration-response curve (J-CRC). The concentration addition (CA) model is the gold standard for studying mixture toxicity. However, the CA model had the predictive blind zone (PBZ) for mixture J-CRC. To solve the PBZ problem, we proposed a segmented concentration addition (SCA) method to predict mixture J-CRC, which was achieved through fitting the left and right segments of component J-CRC and performing CA prediction subsequently. We selected two model compounds including chlortetracycline hydrochloride (CTCC) and oxytetracycline hydrochloride (OTCC), both of which presented J-CRC to Aliivibrio fischeri (AVF). The seven binary mixtures (M1–M7) of CTCC and OTCC were designed according to their molar ratios of 12:1, 10:3, 8:5, 1:1, 5:8, 3:10, and 1:12 referring to the direct equipartition ray design. These seven mixtures all presented J-CRC to AVF. Based on the SCA method, we obtained mixture maximum stimulatory effect concentration (ECm) and maximum stimulatory effect (Em) predicted by SCA, both of which were not available for the CA model. The toxicity interactions of these mixtures were systematically evaluated by using a comprehensive approach, including the co-toxicity coefficient integrated with confidence interval method (CTCICI), CRC, and isobole analysis. The results showed that the interaction types were additive and antagonistic action, without synergistic action. In addition, we proposed the cross point (CP) hypothesis for toxic interactive mixtures presenting J-CRC, that there was generally a CP between mixture observed J-CRC and CA predicted J-CRC; the relative positions of observed and predicted CRCs on either side of the CP would exchange, but the toxic interaction type of mixtures remained unchanged. The CP hypothesis needs to be verified by more mixtures, especially those with synergism. In conclusion, the SCA method is expected to have important theoretical and practical significance for mixture hormesis.

Defect inspection system of nuclear fuel pellet end faces based on machine vision

ABSTRACTIn order to effectively conduct the defect detection of nuclear fuel pellets end face and avoid the leakage of nuclear radiation, a defect detection system for the nuclear fuel pellets end face based on machine vision is proposed. Firstly, aiming at the complexity of the defect detection of nuclear fuel pellets, a set of image acquisition system lighted by left-right symmetric grating is designed. Then, after fusing the images of left-right structured light those cross points are extracted which classified based on the Gaussian mixture model (GMM). Finally, a series of morphological operations such as dilation operation are conducted for the classified points to obtain the defect area of nuclear fuel pellets end face. The experimental results show that this method reduces the influence of complex characteristics of form, texture, and color of the sample end face on the defect detection and relatively good detection results are gained for various defects with 99.5% accuracy. It takes less than 0.4 s to fully meet the requirements of industrial automation testing.

Natural Domain Decomposition Algorithms for the Solution of Time-Harmonic Elastic Waves

We study for the first time Schwarz domain decomposition methods for the solution of the Navier equations modeling the propagation of elastic waves. These equations in the time-harmonic regime are difficult to solve by iterative methods, even more so than the Helmholtz equation. We first prove that the classical Schwarz method is not convergent when applied to the Navier equations and can thus not be used as an iterative solver, only as a preconditioner for a Krylov method. We then introduce more natural transmission conditions between the subdomains and show that if the overlap is not too small, this new Schwarz method is convergent. We illustrate our results with numerical experiments, both for situations covered by our technical two subdomain analysis and situations that go far beyond, including many subdomains, cross points, heterogeneous materials in a transmission problem, and Krylov acceleration. Our numerical results show that the Schwarz method with adapted transmission conditions leads systematically to a better solver for the Navier equations than the classical Schwarz method.

How Dysregulated Ion Channels and Transporters Take a Hand in Esophageal, Liver, and Colorectal Cancer.

Over the last two decades, the understanding of how dysregulated ion channels and transporters are involved in carcinogenesis and tumor growth and progression, including invasiveness and metastasis, has been increasing exponentially. The present review specifies virtually all ion channels and transporters whose faulty expression or regulation contributes to esophageal, hepatocellular, and colorectal cancer. The variety reaches from Ca2+, K+, Na+, and Cl- channels over divalent metal transporters, Na+ or Cl- coupled Ca2+, HCO3- and H+ exchangers to monocarboxylate carriers and organic anion and cation transporters. In several cases, the underlying mechanisms by which these ion channels/transporters are interwoven with malignancies have been fully or at least partially unveiled. Ca2+, Akt/NF-κB, and Ca2+- or pH-dependent Wnt/β-catenin signaling emerge as cross points through which ion channels/transporters interfere with gene expression, modulate cell proliferation, trigger epithelial-to-mesenchymal transition, and promote cell motility and metastasis. Also miRs, lncRNAs, and DNA methylation represent potential links between the misexpression of genes encoding for ion channels/transporters, their malfunctioning, and cancer. The knowledge of all these molecular interactions has provided the basis for therapeutic strategies and approaches, some of which will be broached in this review.

NOMINATION AS THE PRINCIPAL AXIS OF PUSHKIN’S THOUGHT

The article deals with the description of a modeling process of nominative units in A. Pushkin language; the units presenting a nominative field with certain value landmarks. The semantic valence of Pushkin`s word related to a primordial image (archetype) is shown in the ability to evolute extensively the meaning energy in a text prospect. The data for study were the units of two synonymic rows with the core units “ арап ” and “ негр ” functioning in A. Pushkin language. The study aimed at revealing the nomination specificity in the poet language, and characterizing the factors determining a nomination process. The author`s reflective vector in a language material analysis became evident at a deep symbolic level. An analytical procedure to reconstruct a meta-semantic text construct was based on a componential analysis combined with a contextual one, as well as on an interpretation technique and a descriptive method. The findings demonstrated the mentioned nominative units to have a specific axiological value, be implemented within the semantic areas “ своё ” (`my ancestors`, `pride of grateful descendants`) and “ чужое ” (`hostile world, which failed to comprehend and accept him`). And their semantic evolution specifies the text sign space arrangement. A nominative frame of Pushkin`s discourse is determined by a cross point of two destinies disconnected by time - the poet`s great grandfather, Abram Petrovich Hannibal, and Alexander Pushkin, a converging point of “racial” drama and public and creative loneliness drama of personalities rejected and unappreciated by their contemporaries. A semantic “tension” of the author’s idea, its dualism reaches the summit when the self-consciousness reason is fathomed: it is inside негр- арап opposition, where there is a semantic, and wider - a mental point haunting the poet’s reflecting consciousness. The conclusion appears to be conceptually significant: черный дед мой Ганнибал, <...> сходно купленный арап <...> Царю наперсник, а не раб . Semantic increments are exhibited against a rich association background of Pushkin cognition: the poet ‘models’ the text with abundant implication, where every “nominative hint” unfolds under the abundance of a semantic prospect. Major components of the process are intertextually loaded units - precedential names. Their usage forms the basis for a cognitive mechanism to convey implication through an “economical” nominative procedure. The study findings can be used to create semantic dictionaries of a complex type.

Phase-Inversion Waves Propagating in an In-Phase Synchronization on Oscillators Coupled as a Cross

A large number of synchronization phenomena are observed in this world, and investigations and analyses of these phenomena are important in various fields. In this study, phase-inversion waves, which continuously propagate the phase-state between adjacent oscillators on a cross system in which van der Pol oscillators are coupled by inductors, are observed using our simulators and actual circuits. We analyze the phase-inversion waves by using the electric power, phase differences between adjacent oscillators, theoretical frequencies, and instantaneous frequencies, and clarify the penetration mechanism of phase-inversion waves at a cross point by using the phase differences as well as the theoretical and simulated instantaneous frequencies.