Radial Axis Research Articles

Multidirectional Estimation of Arterial Stiffness Using Vascular Guided Wave Imaging with Geometry Correction

We previously found that vascular guided wave imaging (VGWI) could non-invasively quantify transmural wall stiffness in both the longitudinal (r–z plane, 0°) and circumferential (r–θ plane, 90°) directions of soft hollow cylinders. Arterial stiffness estimation in multiple directions warrants further comprehensive characterization of arterial health, especially in the presence of asymmetric plaques, but is currently lacking. This study therefore investigated the multidirectional estimation of the arterial Young's modulus in a finite-element model, in vitro artery-mimicking phantoms and an excised porcine aorta. A longitudinal pre-stretch of 20% and/or lumen pressure (15 or 70 mm Hg) was additionally introduced to pre-condition the phantoms for emulating the intrinsic mechanical anisotropy of the real artery. The guided wave propagation was approximated by a zero-order antisymmetric Lamb wave model. Shape factor, which was defined as the ratio of inner radius to thickness, was calculated over the entire segment of each planar cross section of the hollow cylindrical structure at a full rotation (0°–360° at 10° increments) about the radial axis. The view-dependent geometry of the cross segment was found to affect the guided wave propagation, causing Young's modulus overestimation in four angular intervals along the propagation pathway, all of which corresponded to wall regions with low shape factors (<1.5). As validated by mechanical tensile testing, the results indicate not only that excluding the propagation pathway with low shape factors could correct the overestimation of Young's modulus, but also that VGWI could portray the anisotropy of hollow cylindrical structures and the porcine aorta based on the derived fractional anisotropy values from multidirectional modulus estimates. This study may serve as an important step toward 3-D assessment of the mechanical properties of the artery.

Visual Working Memory Is Independent of the Cortical Spacing Between Memoranda.

The sensory recruitment hypothesis states that visual short-term memory is maintained in the same visual cortical areas that initially encode a stimulus' features. Although it is well established that the distance between features in visual cortex determines their visibility, a limitation known as crowding, it is unknown whether short-term memory is similarly constrained by the cortical spacing of memory items. Here, we investigated whether the cortical spacing between sequentially presented memoranda affects the fidelity of memory in humans (of both sexes). In a first experiment, we varied cortical spacing by taking advantage of the log-scaling of visual cortex with eccentricity, presenting memoranda in peripheral vision sequentially along either the radial or tangential visual axis with respect to the fovea. In a second experiment, we presented memoranda sequentially either within or beyond the critical spacing of visual crowding, a distance within which visual features cannot be perceptually distinguished due to their nearby cortical representations. In both experiments and across multiple measures, we found strong evidence that the ability to maintain visual features in memory is unaffected by cortical spacing. These results indicate that the neural architecture underpinning working memory has properties inconsistent with the known behavior of sensory neurons in visual cortex. Instead, the dissociation between perceptual and memory representations supports a role of higher cortical areas such as posterior parietal or prefrontal regions or may involve an as yet unspecified mechanism in visual cortex in which stimulus features are bound to their temporal order.SIGNIFICANCE STATEMENT Although much is known about the resolution with which we can remember visual objects, the cortical representation of items held in short-term memory remains contentious. A popular hypothesis suggests that memory of visual features is maintained via the recruitment of the same neural architecture in sensory cortex that encodes stimuli. We investigated this claim by manipulating the spacing in visual cortex between sequentially presented memoranda such that some items shared cortical representations more than others while preventing perceptual interference between stimuli. We found clear evidence that short-term memory is independent of the intracortical spacing of memoranda, revealing a dissociation between perceptual and memory representations. Our data indicate that working memory relies on different neural mechanisms from sensory perception.

Scaled radial axes for interactive visual feature selection: A case study for analyzing chronic conditions

In statistics, machine learning, and related fields, feature selection is the process of choosing a smaller subset of features to work with. This is an important topic since selecting a subset of features can help analysts to interpret models and data, and to decrease computational runtimes. While many techniques are purely automatic, the data visualization community has produced a number of interactive approaches where users can make decisions taking into account their domain knowledge. In this paper we propose a new visualization technique based on radial axes that allows analysts to perform feature selection effectively, in contrast to previous radial axes methods. This is achieved by employing alternative scaled axes that provide insight regarding the features that have a smaller contribution to the visualizations. Therefore, analysts can use the technique to carry out interactive backwards feature elimination, by discarding the least relevant features according to the information on the plots and their expertise. Our approach can be coupled with any linear dimensionality reduction method, and can be used when performing analyses of cluster structure, correlations, class separability, etc. Specifically, in this paper we focus on combining the proposed technique with methods designed for classification. Lastly, we illustrate the effectiveness of our proposal through a case study analyzing high-dimensional medical chronic conditions data. In particular, clinicians have used the technique for determining the most important features that discriminate between patients with diabetes and high blood pressure.

“Twisting” Motions in Erupting Coronal Pseudostreamers as Evidence for Interchange Reconnection

Abstract Using white-light observations from the COR1 coronagraph during 2008–2013, we have identified ∼50 eruptive events in which a narrow streamer structure appears to rotate about its radial axis as it rises into the field of view beyond . Extreme-ultraviolet images and potential-field extrapolations suggest that most of these eruptions involve one arcade of a double-lobed pseudostreamer, which is surrounded by open flux of a single polarity. The “twisting” is manifested by the cavity of the erupting lobe, which evolves from a circular to a narrowing oval structure as it is ejected nonradially in the direction of the original X-point. At the same time, the loop legs on the trailing side of the rising cavity/flux rope expand and straighten out, starting at the outer edge of the lobe and progressing inward; this asymmetric opening-up contributes to the impression of a three-dimensional structure twisting away from the observer. On the leading side of the lobe, collapsing cusps are sometimes detected, suggesting the presence of a current sheet where the cavity loops reconnect with the oppositely directed open flux from the adjacent coronal hole. In some events, the inner loops of the cavity/flux rope may continue to expand outward without undergoing interchange reconnection. The transfer of material to open field lines, as well as the lateral confinement of the pseudostreamer by the surrounding coronal holes, acts to produce a relatively narrow, fan-like ejection that differs fundamentally from the large, bubble-shaped ejections associated with helmet streamers.

3D Anisotropy of Solar Wind Turbulence, Tubes, or Ribbons?

Abstract We study the anisotropy with respect to the local magnetic field of turbulent magnetic fluctuations at magnetofluid scales in the solar wind. Previous measurements in the fast solar wind obtained axisymmetric anisotropy, despite that the analysis method allows nonaxisymmetric structures. These results are probably contaminated by the wind expansion that introduces another symmetry axis, namely, the radial direction, as indicated by recent numerical simulations. These simulations also show that while the expansion is strong, the principal fluctuations are in the plane perpendicular to the radial direction. Using this property, we separate 11 yr of Wind spacecraft data into two subsets characterized by strong and weak expansion and determine the corresponding turbulence anisotropy. Under strong expansion, the small-scale anisotropy is consistent with the Goldreich &amp; Sridhar critical balance. As in previous works, when the radial symmetry axis is not eliminated, the turbulent structures are field-aligned tubes. Under weak expansion, we find 3D anisotropy predicted by the Boldyrev model, that is, turbulent structures are ribbons and not tubes. However, the very basis of the Boldyrev phenomenology, namely, a cross-helicity increasing at small scales, is not observed in the solar wind: the origin of the ribbon formation is unknown.

Estimation of Morphological Characteristics in Asymmetrical Myopic Posterior Staphyloma using Optical Coherence Tomography.

PURPOSE:Posterior staphyloma is an ocular complication associated with high myopia and reflects degenerative changes on the sclera. Its morphology is associated with chorioretinal atrophy and myopic maculopathy. The purpose of this study was to validate the efficacy of optical coherence tomography (OCT) in providing a simple estimation of the staphyloma pattern.MATERIALS AND METHODS:Observational case-series study of high myopic patients with posterior staphylomas. Patients were examined using the star scan pattern OCT in different radial planes. Three-dimensional (3D) magnetic resonance tomography was also performed to visualize the anatomical characteristics of the posterior pole. 3D-segmentation and curvature analysis were also performed.RESULTS:Eight patients were totally enrolled in this pilot study. Our study pool consisted of 2 wide macular staphylomas, 2 narrow macular staphylomas, and 4 barrel-shaped staphylomas. Our preliminary results revealed that patients displayed mirror-image distortion in the steeper staphyloma axis. In the barrel-shaped subtype, no image distortion was displayed in any plane.CONCLUSION:We estimated the axis of the smaller base curvature by noting the distortion pattern in the different radial axis. The recognition of pathologic axial myopia is important since there is a risk of permanent vision loss from vision to threatening sequelae.

Magnetic Geared Radial Axis Vertical Wind Turbine for Low Velocity Regimes

In the 21st century, every country is seeking an alternative source of energy especially the renewable sources. There are considerable developments in the wind energy technology in recent years and in more particular on the vertical axis wind turbine (VAWT) as they are modular, less installation cost and portable in comparison with that of the horizontal axis wind turbine (HAWT) systems. The cut-in speed of a conventional wind turbine is 3.5 m/s to 5 m/s. Mechanical geared generators are commonly found in wind technology to step up power conversion to accommodate the needs of the generator. Wind turbine gearboxes suffer from overload problem and frequent maintenance in spite of the high torque density produced. However, an emerging alternative to gearing system is Magnetic Gear (MG) as it offers significant advantages such as free from maintenance and inherent overload protection. In this project, numerical analysis is done on designed magnetic gear greatly affects the performance of the generator in terms of voltage generation. Magnetic flux density is distributed evenly across the generator as seen from the uniform sinusoidal output waveform. Consequently, the interaction of the magnetic flux of the permanent magnets has shown no disturbance to the output of the generator as the voltage generated shows uniform waveform despite the rotational speed of the gears. The simulation is run at low wind speed and the results show that the generator starts generating a voltage of 240 V at a wind speed of 1.04 m/s. This shows great improvement in the operating capability of the wind turbine.

The 4 axes control magnetic bearing for a ventricular assist device

We propose simple homopolar magnetic bearings for a ventricular assist device. The bearings control radial position and inclination around radial axes of the outer rotor. In this paper, magnetic suspension characteristics of two types of the magnetic bearings which differ from each other in magnet arrangement or magnetization direction are compared using three-dimensional magnetic field analysis. The one is whose magnets are set on the outer rotor (Type A). The other is whose magnet is set on the stator (Type B). The radial control force and tilting control torque of Type A is 17% and 9.5% higher than that of Type B. The Type A magnetic bearing is made based on the analysis results and measured its magnetic flux density and axial restoring force. The bearing indicates the axial stiffness of about 2 N/mm.

Manifestations of geometric phases in a proton electric-dipole-moment experiment in an all-electric storage ring

We consider a proton electric-dipole-moment experiment in an all-electric storage ring when the spin is frozen and local longitudinal and vertical electric fields alternate. In this experiment, the geometric (Berry) phases are very important. Due to the these phases, the spin rotates about the radial axis. The corresponding systematic error is rather important while it can be canceled with clockwise and counterclockwise beams. The geometric phases also lead to the spin rotation about the radial axis. This effect can be canceled with clockwise and counterclockwise beams as well. The sign of the azimuthal component of the angular velocity of the spin precession depends on the starting point where the spin orientation is perfect. The radial component of this quantity keeps its value and sign for each starting point. When the longitudinal and vertical electric fields are joined in the same sections without any alternation, the systematic error due to the geometric phases does not appear but another systematic effect of the spin rotation about the azimuthal axis takes place. It has opposite signs for clockwise and counterclockwise beams.

Revealing chiral cell motility by 3D Riesz transform-differential interference contrast microscopy and computational kinematic analysis

Left–right asymmetry is a fundamental feature of body plans, but its formation mechanisms and roles in functional lateralization remain unclear. Accumulating evidence suggests that left–right asymmetry originates in the cellular chirality. However, cell chirality has not yet been quantitatively investigated, mainly due to the absence of appropriate methods. Here we combine 3D Riesz transform-differential interference contrast (RT-DIC) microscopy and computational kinematic analysis to characterize chiral cellular morphology and motility. We reveal that filopodia of neuronal growth cones exhibit 3D left-helical motion with retraction and right-screw rotation. We next apply the methods to amoeba Dictyostelium discoideum and discover right-handed clockwise cell migration on a 2D substrate and right-screw rotation of subcellular protrusions along the radial axis in a 3D substrate. Thus, RT-DIC microscopy and the computational kinematic analysis are useful and versatile tools to reveal the mechanisms of left–right asymmetry formation and the emergence of lateralized functions.

Role of the deformation imaging in the evaluation of patients with cardiomyopathy

AbstractCardiomyopathies are a heterogeneous group of diseases recognized by specific patterns of myocardial morphology and function. Myocardial deformation imaging, using strain and strain rate as main parameters, is a novel echocardiographic method for the evaluation of global and regional myocardial function. Speckle tracking imaging is currently the best technique for the evaluation of myocardial deformation in the longitudinal, radial, and circumferential axis. The aim of the following review was to analyze the potential role of the deformation imaging in the evaluation of cardiomyopathies, focusing on the recent developments regarding the differential and early diagnosis as well as the prognosis of the disease.

Association of VACTERL with truncus arteriosus, left-sided aortic arch, hypoplastic pulmonary arteries, and severe radial axis defect

Background: VACTERL association is usually a sporadic disorder, the possible etiologies of which have been proposed as familial as well as multiple genetic and environmental factors. VACTERL association usually consists of at least three of the core features of vertebral defects, anal atresia, cardiac defects, tracheoesophageal fistula, renal anomalies, and limb abnormalities. Vertebral anomalies, cardiac malformations, renal anomalies, and limb malformations have been reported to occur in 60-80%, 40-80%, 50-80%, and 40-50% of the patients, respectively. Among the cardiac anomalies, ventricular septal defect is the most prevalent one. Truncus arteriosus is a rarely associated defect. The radial anomalies are the most classic limb defects with different severity levels (types I-IV). Although radial axis defect usually accompanies this association, complete absence of radius is reported only in one third of the cases. Case report: In this case study, we reported a neonate having this association consisting of severe cyanotic congenital heart defect (truncus arteriosus) and unilateral type IV radial aplasia. Conclusion: VACTERL association components can have various new findings.

A yttrium aluminosilicate glass fiber with graded refractive index fabricated by melt‐in‐tube method

AbstractA graded‐index fiber with yttrium aluminosilicate (YAS) glass core was fabricated by a “Melt‐in‐Tube” method. The refractive index and stress profiles of the fibers exhibit a highly symmetrical gradient tendency along the radial axis which is in accordance with the results of element migration. Based on the formation mechanism of YAS glass core, the relationships between the refractive index/stress profile and the spontaneous migration are discussed. A linear all‐fiber laser based on the obtained fiber shows a laser output threshold of 11.48 mW and slope efficiency of 8.3%. The near‐field beam intensity distribution of fiber laser with spectrum FWHM of 0.24 nm indicates the good laser beam quality. The facile “Melt‐in‐tube” method was proved to be reliable in designing graded‐index fiber through the dissolution and diffusion process, which is more advanced than commonly used “Rod‐in‐tube” method.

PLETHORA transcription factors orchestrate de novo organ patterning during Arabidopsis lateral root outgrowth

Plant development is characterized by repeated initiation of meristems, regions of dividing cells that give rise to new organs. During lateral root (LR) formation, new LR meristems are specified to support the outgrowth of LRs along a new axis. The determination of the sequential events required to form this new growth axis has been hampered by redundant activities of key transcription factors. Here, we characterize the effects of three PLETHORA (PLT) transcription factors, PLT3, PLT5, and PLT7, during LR outgrowth. In plt3plt5plt7 triple mutants, the morphology of lateral root primordia (LRP), the auxin response gradient, and the expression of meristem/tissue identity markers are impaired from the "symmetry-breaking" periclinal cell divisions during the transition between stage I and stage II, wherein cells first acquire different identities in the proximodistal and radial axes. Particularly, PLT1, PLT2, and PLT4 genes that are typically expressed later than PLT3, PLT5, and PLT7 during LR outgrowth are not induced in the mutant primordia, rendering "PLT-null" LRP. Reintroduction of any PLT clade member in the mutant primordia completely restores layer identities at stage II and rescues mutant defects in meristem and tissue establishment. Therefore, all PLT genes can activate the formative cell divisions that lead to de novo meristem establishment and tissue patterning associated with a new growth axis.

Dab1 contributes differently to the morphogenesis of the hippocampal subdivisions.

The hippocampal formation (HF) is morphologically and functionally distinguishable into the subdivisions, such as the dentate gyrus (DG), subiculum, and Ammon's horn. The Ammon's horn is further divided into the CA (Cornu Ammonis)1, CA2, and CA3. The Reelin-Dab1 signal is essential for the morphogenesis of the mammalian brain. In the neocortex of Reelin-Dab1 signal mutants the laminar pattern of the neurons is disrupted along the radial axis. Morphological abnormalities in the HF of the Reelin-Dab1 mutants were known, but how these abnormalities appear during development had not been extensively studied. We examined the morphology of the well-developed Dab1 deficient HF by staining with a silver impregnation method in this report, and found that disruption of lamination in the CA1, CA3, and DG was different. Abnormalities observed in the development of Dab1 deficient CA1 were similar to those reported in the neocortical development, while Dab1 deficient CA3 neuronal progenitors radially spreaded beyond presumptive pyramidal layer. The intermediate progenitor cells ectopically located in the Dab1 deficient DG, but neurogenesis was normal in the CA1 and CA3. These observations suggest that the morphogenesis in these HF subdivisions employs different developmental mechanisms involving Dab1 function.

Differential Myocardial Fibre Involvement by Strain Analysis in Patients With Aortic Stenosis

Aortic stenosis (AS) is the most common valvular heart disease and can result in left ventricular (LV) systolic impairment. LV myocardial fibres are organised in layers: the subendocardial layer is orientated longitudinally and the subepicardial layer circumferentially. We hypothesised that there is differential involvement of myocardial fibres in patients with aortic stenosis. We performed multi-directional, multi-layered systolic strain analysis in 70 patients (aged 72±10.7years) with varying grades of AS severity (mean gradient 32.3±20mmHg, aortic valve area 1.1±0.6cm2) and in 30 controls. Clinical, demographic and resting echocardiographic data were recorded. Left ventricular subendocardial and subepicardial systolic strains were measured in the longitudinal, radial and circumferential axes. Systolic subendocardial strain was significantly higher than subepicardial strain in all three axes in patients and in controls. There were significant differences in longitudinal, but not in circumferential and radial strain, or left ventricular ejection fraction (LVEF), between patient groups. Aortic valve mean gradient (MG) and valve area (AVA) correlated better with subendocardial longitudinal strain (r=0.548, p<0.001; r=-0.54, p<0.001 respectively) than with subepicardial longitudinal strain (r=0.496, p<0.001, r=-0.544, p<0.001 respectively). Correlations between circumferential and radial strain and MG or AVA were poor. There was differential impairment in LV systolic strain in all three cardiac axes in patients with AS. Left ventricular longitudinal strain impairment was proportional to AS severity. Subendocardial longitudinal strain correlated better with AS severity than subepicardial longitudinal strain while correlations between circumferential and radial strain and AS severity were weak.

Slow rotation of a spherical particle inside an elastic tube

In this paper, we present an analytical calculation of the rotational mobility functions of a particle rotating on the centerline of an elastic cylindrical tube whose membrane exhibits resistance towards shearing and bending. We find that the correction to the particle rotational mobility about the cylinder axis depends solely on membrane shearing properties while both shearing and bending manifest themselves for the rotational mobility about an axis perpendicular to the cylinder axis. In the quasi-steady limit of vanishing frequency, the particle rotational mobility nearby a no-slip rigid cylinder is recovered only if the membrane possesses a non-vanishing resistance towards shearing. We further show that for the asymmetric rotation along the cylinder radial axis, a coupling between shearing and bending exists. Our analytical predictions are compared and validated with corresponding boundary integral simulations where a very good agreement is obtained.

Wnt9a Can Influence Cell Fates and Neural Connectivity across the Radial Axis of the Developing Cochlea.

Vertebrate hearing organs manifest cellular asymmetries across the radial axis that underlie afferent versus efferent circuits between the inner ear and the brain. Therefore, understanding the molecular control of patterning across this axis has important functional implications. Radial axis patterning begins before the cells become postmitotic and is likely linked to the onset of asymmetric expression of secreted factors adjacent to the sensory primordium. This study explores one such asymmetrically expressed gene, Wnt9a, which becomes restricted to the neural edge of the avian auditory organ, the basilar papilla, by embryonic day 5 (E5). Radial patterning is disrupted when Wnt9a is overexpressed throughout the prosensory domain beginning on E3. Sexes were pooled for analysis and sex differences were not studied. Analysis of gene expression and afferent innervation on E6 suggests that ectopic Wnt9a expands the neural-side fate, possibly by re-specifying the abneural fate. RNA sequencing reveals quantitative changes, not only in Wnt-pathway genes, but also in genes involved in axon guidance and cytoskeletal remodeling. By E18, these early patterning effects are manifest as profound changes in cell fates [short hair cells (HCs) are missing], ribbon synapse numbers, outward ionic currents, and efferent innervation. These observations suggest that Wnt9a may be one of the molecules responsible for breaking symmetry across the radial axis of the avian auditory organ. Indirectly, Wnt9a can regulate the mature phenotype whereby afferent axons predominantly innervate neural-side tall HCs, resulting in more ribbon synapses per HC compared with abneural-side short HCs with few ribbons and large efferent synapses.SIGNIFICANCE STATEMENT Wnts are a class of secreted factors that are best known for stimulating cell division in development and cancer. However, in certain contexts during development, Wnt-expressing cells can direct neighboring cells to take on specific fates. This study suggests that the Wnt9a ligand may play such a role in the developing hearing organ of the bird cochlea. This was shown through patterning defects that occur in response to the overexpression of Wnt9a. This manipulation increased one type of sensory hair cell (tall HCs) at the expense of another (short HCs) that is usually located furthest from the Wnt9a source. The extraneous tall HCs that replaced short HCs showed some physiological properties and neuronal connections consistent with a fate switch.

3D effects on vortex-shedding flow and hydrodynamic coefficients of a vertically oscillating cylinder with a bottom-attached disk

Vortex-shedding flow induced by the vertical oscillation of a cylinder with bottom-attached disks of different diameter ratio D d/D c and thickness ratio t d/D c is studied by a 3D (three-dimensional) numerical model developed in this paper, and compared with the results obtained through 2D (two-dimensional) numerical model. The high-order upwind scheme is applied to stabilize the computation, and convergence is accelerated by the multi-grid method. Qualitative and quantitative analyses of the differences between the 2D and 3D simulation results reveal the 3D effect on the flow field characteristics and hydrodynamic coefficients of the vertically oscillating cylinder with a bottom-attached disk. The 3D effect on the fluid field is mainly reflected in the significance of three vortex-shedding patterns: ω x has a greater effect on the flow fields around the sharp edges relative to the vortices generated in the 2D simulation. In the slice along the axial orientation, the vortex effect of ω y along the radial axis is smaller than that of ω x along the circumferential direction, indicating the radial effect on the velocity more pronounced than the circumferential effect around the sharp edges of the disk. The rotational interaction ω z of the fluid in the horizontal plane during the heave motion is insignificant. Based on the 2D and 3D simulation results, the turning points that separate the increasing regimes of the added mass coefficient and damping ratio are identified. The dependence of the turning point on the diameter ratio D d/D c and thickness ratio t d/D c are discussed in detail.

Phase transition of block copolymer/homopolymer binary blends under 2D confinement

Constraints imposed by nanometer scale confinement lead to the changes in bulk equilibrium behavior of block copolymers (BCPs). Cylindrical pores with diameter corresponding to the equivalent length of several copolymer chains have been employed to investigate the influence of two-dimensional (2D) confinement on the behavior of BCPs. Herein, we reported the microdomain transition behavior of block copolymer/homopolymer (AB/A) binary blends in cylindrical confinement. Lamellae forming poly(styrene-b-butadiene) (PS-b-PBD) and PS homopolymers (hPS) were drawn into the pores of anodized aluminum oxide (AAO) and isolated by selective etching of the AAO templates. Concentric ring morphologies of neat PS-b-PBD in the cylindrical confinement varied with on the addition of hPS. Given the volume fraction of homopolymers, the phase behavior of polymer blends was dependent on the molecular weight of homopolymers. When the ratio between the molecular weight of hPS and PS block was much lower than unity (α«1) (i.e., wet brush regime), the concentric ring structure was transformed into helical or spherical structure depending on the volume fraction of hPS. For α≈1 (i.e., dry brush regime), additional hPS chains were localized at the center of concentric ring where the entropic penalty of copolymer chains induced by confinement is maximized. Over the capability of hPS in the BCP domains in radial axis, the phase transition into microemulsions occurred in the dry brush regime. In both wet and dry brush regimes, the effect of hPS on the phase transition of BCP was significantly enhanced in the nanoscale 2D confinement compared to the bulk state due to the loss of conformational entropy of polymer chains.