3D Plate Research Articles

Tuning Organic Microcrystal Morphologies through Crystal Engineering Strategies toward Anisotropic Optical Waveguide.

The construction of organic optoelectronic materials with desirable size and morphology remains a challenge now. Crystal engineering strategies (polymorphs and cocrystals) provide convenience for tailoring molecular packing and further controlling the growth morphology and photofunctionality of materials. Herein, we prepare polymorphic 2D plate crystals and 3D microhelixes by assembly of a cyanostilbene derivative (2-(3',5'-bis(trifluoromethyl)-biphenyl-4-yl)-3-(4-(pyridin-4-yl)phenyl)acrylonitrile, CF3-CN-Py). The former emits blue emission, while the latter emits green emission. Different crystallization environments contribute to the adjustable morphologies. Then, novel cocrystals are fabricated with the introduction of 1,4-diiodotetrafluorobenzene (FDIB) to CF3-CN-Py. Both molecular conformation and packing are totally changed in the cocrystal system. Such cocrystal displays a 1D sky-blue emissive rod shape on account of a long-range ordered π-stacking of molecules. In addition, the 2D plate crystal and 1D rod cocrystal are further applied to optical waveguides. In the plate crystal, a packing of transition dipole moment (μ) inclined to the upper surface leads to an anisotropic optical waveguide. In the cocrystal, owing to the nearly horizontal μ orientation, the cocrystal exhibits light propagation along the primary growth direction and a low optical loss coefficient. The present study supplies an effective way to construct materials with controlled morphology and optical waveguide.

Photocatalytic behavior of Ba(Sb/Ta)2O6 perovskite for reduction of organic pollutants: Experimental and DFT correlation

We have synthesized closely packed hexagonal 2D plates and clustered nanoparticle morphologies of Ba(Sb/Ta)2O6 (BSTO) perovskite via the polymerizable complex method for photocatalytic dye degradation activities. The BSTO crystallized in a hexagonal structure. The presence of Ba2+, Sb5+, Ta5+, and O2− chemical states identified from XPS confirmed the formation of mixed Ba(Sb/Ta)2O6 phase accompanied with a minor amount of TaOx. Furthermore, BSTO showed excellent photocatalytic activity for the degradation of various organic dyes. The kinetic studies revealed 65.9%, 77.3%, 89.8%, and 84.2%, of Crystal Violet (CV), Methylene Blue (MB), Rhodamine blue (RhB), and Methylene Orange (MO), respectively, after irradiation of 180 min without using a cocatalyst. The formation of O2− and OH−surface radicals, which are believed to facilitate the degradation of the dyes, are unveiled through first-principles Density Functional Theory (DFT) calculations and scavenging studies. Our results suggest that BSTO holds promise as an excellent photocatalyst with better degradation efficiency for various organic dyes.

A Comparative Assessment of the Management of Mandibular Fracture using 3D Plates and 2D Miniplates

A Comparative Assessment of the Management of Mandibular Fracture using 3D Plates and 2D Miniplates

An In Vitro Evaluation of a Novel Design Z Plate for Fixation of Mandibular Symphysis and Parasymphysis Fractures-A Finite Element Analysis.

Surgical management of mandibular symphysis and parasymphysis fractures has evolved from rigid fixation to semi-rigid fixation with miniplate osteosynthesis. Various miniplate systems have been developed in recent years including three-dimensional miniplate, microplates and bioresorbable plate, and their advantages and disadvantages have been compared and studied. To overcome the shortcomings of 3D plating system such as difficulty in adaptation and fixation in fractures involving the mental nerve, a novel Z plate has been designed by our institute. An in vitro study was performed to evaluate the biomechanical behaviour of the newly designed Z plate with 3D plate and two-miniplate system using finite element analysis. Our study showed total structural deformation of 0.17mm and 0.31mm of newly designed Z plate after canine loading and molar loading, respectively. The equivalent von Mises force for plate after canine loading had shown the following results-Z plate showed values of 121.3MPa and 58.40MPa after molar loading. Our study concluded that the Z plate produces lowest stresses, lesser total structural deformation, superior stability and support in comparison with the 3D plate and two-miniplate system.

Application of Anatomically Designed 2-Dimensional V Plate in Management of Mandible Fracture: A Pilot Study.

Mandible is the only mobile facial jaw bone and it aides in various functions such as phonation and mastication. Therefore, management of mandible fracture becomes inevitable due to its functional and anatomical importance. Fracture fixation methods and techniques have steadily evolved with various osteosynthesis systems. In this article, we discuss the management of mandible fracture using a newly designed two-dimensional (2D) hybrid V-shaped plate. In this paper, we have evaluated the efficacy of the newly developed 2D V-shaped locking plate in the management of mandibular fractures. We have assessed 12 cases of different mandibular fractures ranging from symphysis, parasymphysis, angle and subcondylar region. Treatment outcome was assessed both clinically and radiologically at regular intervals with various intraoperative and postoperative parameters. Results of this study suggest that fixation of mandible fracture with the 2D hybrid V-shaped plate facilitates anatomic reduction and functional stability and carries a low morbidity and infection rate. The 2D anatomic hybrid V-shaped plate can be a suitable alternative to conventional miniplate and 3D plates as it offers satisfactory anatomic reduction and functional stability. Positioning the plate in relation to the mental nerve and plate adaptation along the angle region are much easier.

Buckling analysis of cracked orthotropic 3D plates and shells via an isogeometric-reproducing kernel particle method

This paper aims to develop a three-dimensional isogeometric-reproducing kernel particle method (IGA-RKPM) coupling approach to study the buckling behavior of cracked isotropic and orthotropic plate and shell structures. The IGA and RKPM-based meshfree methods are coupled successfully through a reproducing condition in the physical domain that guarantees the higher-order polynomial continuity of basis functions and overcomes the barrier of global parameterization in the physical domain. The resulting coupling approach not only preserves the geometry exactness and offers a higher-order approximation based on IGA basis functions but also allows local refinement flexibility. Linear eigenvalue buckling analyses for cracked orthotropic plate and shell structures have been carried out within the framework of the proposed coupling approach. The effects of several parameters such as the crack length ratio, thickness-to-length ratio, and orthotropy angle on the critical buckling stress of the structures have been investigated in detail under different boundary and loading conditions. The efficacy and robustness of the proposed coupling approach have been demonstrated by comparing the present results with those available in literature.

Topological Design of Freely Vibrating Bi-Material Structures to Achieve the Maximum Band Gap Centering at a Specified Frequency

AbstractThe topological design of structures to avoid vibration resonance for a certain external excitation frequency is often desired. This paper considers the topology optimization of freely vibrating bi-material structures with fixed/varying attached mass positions, targeting at maximizing the frequency band gap centering at a specified frequency. A band gap measure index is proposed to measure the size of the band gap with a specified center frequency. Aiming at maximizing this measure index, the topology optimization problem is formulated on the basis of the material-field series-expansion (MFSE) method, which greatly reduces the number of design variables and at the same time keeps the capability to describe relatively complex structural topologies with clear boundaries. As the considered optimization problem is highly non-linear and may yield multiple local minima, a sequential Kriging-based optimization solution strategy is employed to effectively solve the optimization problem. This solution strategy exhibits a relatively strong global search capability and requires no sensitivity information. With the present topology optimization model and the gradient-free algorithm, relative large band gaps with specified center frequencies have been obtained for two-dimensional (2D) beams and three-dimensional (3D) plates, without specifying the frequency orders between which the desired band gap occurs in prior.

Topology optimization of clutch drive plate for commercial vehicles

he drive plate is one of the main components of the clutch disc which transmits the torque from engine to transmission. For commercial vehicle applications, the drive plate works under immense torsional forces thanks to high engine torque values. Therefore, high durability is expected during the operational life of the clutch disc drive plate. On the other hand, the lightweight of the vehicle components has an important role in CO2 emission standards. To be able to assure this regulation, companies conduct studies for decreasing the vehicle mass. In this study, the drive plate's 3D CAD data is created based on the current design by using CATIA solid creation software. Finite Element Analysis (FEA) was carried out in a statical analysis tool and to be verified for real-life working conditions. The topology optimization was performed using CAE software (ANSYS) in order to reduce the weight of the drive plate without compromising on mechanical durability. The optimized design was proposed based on topology optimization outputs. The strength of the proposed design was investigated by using FEA analysis and results are compared to the acceptance criteria of the material. The optimized geometry is equally durable and lighter in weight compared to the existing model. Mass was decreased %18 without compromising mechanical durability.

Commissioning of optical surface imaging systems for cranial frameless stereotactic radiosurgery.

PurposeThis study aimed to evaluate and compare different system calibration methods from a large cohort of systems to establish a commissioning procedure for surface‐guided frameless cranial stereotactic radiosurgery (SRS) with intrafractional motion monitoring and gating. Using optical surface imaging (OSI) to guide non‐coplanar SRS treatments, the determination of OSI couch‐angle dependency, baseline drift, and gated‐delivered‐dose equivalency are essential.MethodsEleven trained physicists evaluated 17 OSI systems at nine clinical centers within our institution. Three calibration methods were examined, including 1‐level (2D), 2‐level plate (3D) calibration for both surface image reconstruction and isocenter determination, and cube phantom calibration to assess OSI‐megavoltage (MV) isocenter concordance. After each calibration, a couch‐angle dependency error was measured as the maximum registration error within the couch rotation range. A head phantom was immobilized on the treatment couch and the isocenter was set in the middle of the brain, marked with the room lasers. An on‐site reference image was acquired at couch zero, the facial region of interest (ROI) was defined, and static verification images were captured every 10° for 0°–90° and 360°–270°. The baseline drift was assessed with real‐time monitoring of the motionless phantom over 20 min. The gated‐delivered‐dose equivalency was assessed using the electron portal imaging device and gamma test (1%/1mm) in reference to non‐gated delivery.ResultsThe maximum couch‐angle dependency error occurs in longitudinal and lateral directions and is reduced significantly (P < 0.05) from 1‐level (1.3 ± 0.4 mm) to 2‐level (0.8 ± 0.3 mm) calibration. The MV cube calibration does not further reduce the couch‐angle dependency error (0.8 ± 0.2 mm) on average. The baseline drift error plateaus at 0.3 ± 0.1 mm after 10 min. The gated‐delivered‐dose equivalency has a >98% gamma‐test passing rate.ConclusionA commissioning method is recommended using the 3D plate calibration, which is verified by radiation isocenter and validated with couch‐angle dependency, baseline drift, and gated‐delivered‐dose equivalency tests. This method characterizes OSI uncertainties, ensuring motion‐monitoring accuracy for SRS treatments.

Experimental and analytical investigation for fatigue crack growth characteristics of an aero-engine fan disc

Crack growth evaluation should be performed to certify that the fan disc is capable of maintaining adequate integrity in presence of cracks. The spin test was carried out using the pre-flawed fan disc to obtain a more intensive insight of crack growth characteristic in the bore area. The variation of the surface crack length was measured by the replication method, and then the crack surface fractography was observed with scanning electron microscope (SEM). Both 3D numerical simulation and rectangular plate model were utilized to predict growth behavior of this crack. The crack surface fractography revealed a typical striated transgranular fatigue fracture characteristic. The comparison of the spin test result and the predicted crack growth showed that the numerical and theoretical analysis provided a good prediction for crack growth behavior for the fan disc. Taking into account the effect of plasticity-induced crack closure, the crack growth disparity at the disk surface and interior was analyzed and as a result, the shape of crack propagation front can be described more realistically.

Hip And Knee Abductor Moments In Normal Subjects And Subjects With Idiopathic Scoliosis During Level Walking: Comparative Study

Background: Kinetic analysis appears to be useful in providing objective information regarding the gait abilities of scoliotic patients, which is difficult to be observed in a clinical setting. Objective: the aim of the study was to analyze and compare the hip and knee peak abductor moments in subjects with idiopathic scoliosis and normal subjects during level walking. Methodology: Forty-four male subjects was aged 14-17 years participated in the study. They were assigned into two groups, scoliosis, and control groups. The scoliosis group included 22 subjects with idiopathic moderate right dorso-lumbar curve. The control group contained normal 22 subjects. 3D motion analysis system and force plates were used for data collection for hip and knee abductor moment. MANOVA was used to study the difference between normal and scoliotic groups’ hip and knee abductor moments in both lower limbs at an alpha level of significance of 0.05. Results: During free walking, there was a significant increase in the hip abductor moment contralateral to the scoliotic side, while the ipsilateral side showed non-significant increase when compared with normal subjects. There was a significant increase in the knee abductor moment ipsilateral and contralateral to the scoliotic side when compared with normal. Conclusion: Idiopathic scoliosis could affect the hip and knee gait kinetics in the frontal plane.

Comparison and evaluation of biomechanical stability of customized plate over monocortical screws, bicortical screws and 3d plate in mandibular fractures – An in-vitro study

Comparison and evaluation of biomechanical stability of customized plate over monocortical screws, bicortical screws and 3d plate in mandibular fractures – An in-vitro study

Enhancement of anti-inflammatory and immunomodulatory effects of adipose-derived human mesenchymal stem cells by making uniform spheroid on the new nano-patterned plates

Human mesenchymal stem cells (MSCs) are known to have anti-inflammatory and immunomodulatory functions; thus, several MSC products have been applied as cell therapy in clinical trials worldwide. Recent studies have demonstrated that MSC spheroids have superior anti-inflammatory and immunomodulatory functions to a single cell suspension. Current methods to prepare MSC spheroids include hanging drop, concave microwell aggregation, spinner flask, and gravity circulation. However, all these methods have limitations such as low scalability, easy cell clumping, low viability, and irregular size distribution. Here, we present a nano-patterned culture plasticware named PAMcell™ 3D plate to overcome these limitations. Nano-sized silica particles (700 nm) coated with RGD peptide were arrayed into fusiform onto the PLGA film. This uniform array enabled the seeded MSCs to grow only on the silica particles, forming uniform-sized semi-spheroids within 48 h. These MSC spheroids have been shown to have enhanced stemness, anti-inflammatory, and immunomodulatory functions, as revealed by the increased expression of stem cell markers (Oct4, Sox2, and Nanog), anti-inflammatory (IL-10, TSG6, and IDO), and immunomodulatory molecules (HGF, VEGF, CXCR4) both at mRNA and protein expression levels. Furthermore, these MSC spheroids demonstrated an increased palliative effect on glycemic control in a multiple low-dose streptozotocin-induced diabetes model compared with the same number of MSC single cell suspensions. Taken together, this study presents a new method to produce uniform-sized MSC spheroids with enhanced anti-inflammatory and immunomodulatory functions in vitro and in vivo.

Compressive damage modeling of fiber-reinforced composite laminates using 2D higher-order layer-wise models

A refined progressive damage analysis of fiber-reinforced laminated composites subjected to compressive loads is presented here. The numerical analysis exploits higher-order theories developed using the Carrera Unified Formulation, specifically 2D plate theories with Lagrange polynomials to enhance the kinematic approximation through each ply's thickness resulting in a layer-wise structural model. The CODAM2 material model, based on continuum damage mechanics, governs the intralaminar composite damage. The Hashin criteria and the crack-band approach provides failure initiation and propagation, respectively. Fiber micro-buckling and kinking is taken into account via the use of nonlinear post-peak softening models. It is shown that linear-brittle stress-strain softening is effective for accurate compressive strength predictions. A series of numerical assessments on coupon-level composite laminates is carried out to verify the proposed numerical framework while its validation is demonstrated by successfully applying the numerical tool to test cases for which experimental data is available from the literature. Various through-the-thickness structural models are evaluated to provide insights for proper modeling. Numerical assessments considered quasi-isotropic laminates, the compressive strength and size-effects under brittle fracture of notched laminates, and progressive damage characteristics due to stable crack growth in compact compression tests. The results show the possibility of using coarser meshes than those used in standard FEM approaches as the accuracy of predictions is preserved through the use of higher-order structural theories.

Free Vibration Analysis of Laminated Composite Double-Plate Structure System with Elastic Constraints Based on Improved Fourier Series Method

An analytical model of laminated composite double-plate system (LCDPS) is established, which efficiently analyzes the common 3D plate structure in engineering applications. The proposed model combines the first-order shear deformation theory (FSDT) and the classical delamination theory, and then the LCDPS’s vibration characteristics are investigated. In the process of analysis, the improved Fourier series method (IFSM) is used to describe the displacement admissible function of the LCDPS, which can remove the potential discontinuities at the boundaries. Five sets of artificial springs are introduced to simulate the elastic boundary constraints, and the restraints of the Winkler elastic layer can be adjustable. The improved Fourier series is substituted into the governing equations and boundary conditions; then, applying the Rayleigh–Ritz method, we take all the series expansion coefficients as the generalized coordinates. After that, a set of standard linear algebraic equations was obtained. On this basis, the natural frequency and mode shapes of the LCDPS can be obtained by solving the standard eigenvalue problem. By the discussion of numerical examples and the comparison with those of the reports in the literature, the convergence and the reliability of the present approach are validated. Finally, the parametric investigations of the free vibration with complex boundary conditions are carried out, including the influence of boundary conditions, lamination scheme, plate geometric parameters, and elastic coefficient between two plates.

3D Metallic Plate Lens Antenna based Beamspace Channel Estimation Technique for 5G Mmwave Massive MIMO Systems

Beamspace channel estimation mechanism for massive MIMO (multiple input multiple output) antenna system presents a major process to compensate the 5G spectrum challenges caused by the proliferation of information from mobile devices. However, this estimation is required to ensure the perfect channel state information (CSI) for lower amount of Radio Frequency (RF) chains for each beam. In addition, phase shifter (PS) components used in this estimation need high power to select the beam in the desired direction. To overcome these limitations, in this work, we propose Regular Scanning Support Detection (RSSD) based channel estimation mechanism. Moreover, we utilise a 3D lens antenna array having metallic plate and a switch in our model which compensates the limitation of phase shifters. Simulation results show that the proposed RSSD based channel estimation surpasses traditional technique and SD based channel estimation even in lower SNR area which is highly desirable in the millimeter wave (mmWave) massive MIMO systems.

Factors contributing to racial differences in gait mechanics differ by sex

BackgroundRacial differences in gait mechanics have been recently reported, but we don’t know what factors may drive differences in gait and whether these factors are innate or modifiable. The answers to those questions will inform both basic research and clinical interventions and outcomes. Research questionDo anthropometric, strength, and health status measures explain racial differences in gait between African Americans (AA) and white Americans (WA)? MethodsVenous blood samples, anthropometric measures, lower extremity strength, and an assessment of health status were collected from 92 participants (18–30 years old) as part of an Institutional Review Board-approved study. 3D motion capture and force plate data were recorded during 7 walking trials at set regular (1.35 m/s) and fast (1.6 m/s) speeds. Racial differences in gait were identified at both speeds. Correlations between anthropometric, strength, and health status independent variables and outcome measures were computed after stratifying data by sex. Stepwise linear regression models evaluated whether the inclusion of anthropometric, strength, and health status independent variables explained racial effects. ResultsIn males, no racial differences in gait were explained by independent variables. Q-angle and ankle dorsiflexion strength accounted for racial differences in self-selected walking speed in females. Racial differences in ankle plantarflexion angle were explained by ankle plantarflexion strength differences. SignificanceFactors that explain racial differences in gait in females were both innate and modifiable. These data make clear that it is important to include racially diverse normative gait databases in research studies. These results also identify potential intervention targets aimed at reducing racial health disparities.

Comparitive assessment of bite forces in subjects treated for anterior mandibular fractures with 3-dimensional plates and standard miniplates

Background: Loss of masticatory function is one of the important effects of mandibular fractures. Therefore the therapeutic goal of management is to restore original anatomic form and function. Considering this, maximal bite force could be a major factor for evaluating the success of treatment. Objective: The purpose of this study was to compare the efficiency of 2.0mm 3-Dimensional plates and two standard 2.0 mm Miniplates in the fixation of anterior mandibular fractures i.e, the parasymphysis and symphysis fractures on the basis of bite force and other clinical parameters. Materials and Methods: The study was conducted on 30 patients with isolated fractures of anterior mandible region. The patients were categorized into two groups with 15 patients in each group. In group A patients were treated with 3-Dimensional miniplate and in group B patients were treated with two conventional Miniplates and these patients were evaluated pre-operatively, immediate post-op, 1st week, 4th week, 3rd month and 6th post-op months using bite force and other clinical parameters. Results: The study results revealed no statistically significant difference between the study groups with respect to root damage and mal-union. There was occlusal discrepancy, mobility of fracture segments, and post-op infection observed in Conventional plate group which was absent in 3D plate group. One patient in Conventional plates group had to undergo implant retrieval due to persistent infection and experienced neurosensory deficit even after 6th post-op month. The bite force measurement between the study groups showed statistical significant increase of bite force in the right premolar and right molar regions at 4th post-op month, 3rd post-op month and 6thpost op-month. In 3D plate group, patients showed increased bite force values in comparison to Conventional plates group throughout the follow up intervals. Conclusion: This study concluded that the use of 3D miniplates in anterior mandibular fractures

Nonlinear finite element analysis within strain gradient elasticity: Reissner-Mindlin plate theory versus three-dimensional theory

Nonlinear plate bending within Mindlin's strain gradient elasticity theory (SGT) is investigated by employing somewhat non-standard finite element methods. The main goal is to compare the bending results provided by the geometrically nonlinear three-dimensional (3D) theory and the geometrically nonlinear Reissner–Mindlin plate theory, i.e., the first-order shear deformation plate theory (FSDT), within the SGT. For the 3D theory, the nonlinear Green–Lagrange strain relations are adopted, while the von Kármán nonlinear strains are employed for the FSDT. The matrix-vector forms of the energy functionals are derived for both models. In order to perform the corresponding finite element discretizations, a quasi-C1-continuous 4-node tetrahedral solid element and a quasi-C1-continuous 6-node triangular plate element are employed for the 3D model and plate model, respectively. The first-order derivatives of the primal problem quantities are employed as additional nodal values to respond to the continuity requirements of class C1. A variety of computational results highlighting the differences between the 3D and FSDT models are given for two different plate geometries: a rectangular plate with a circular hole and an elliptical plate.

Two miniplates versus 3-dimensional plate in the management of mandibular subcondylar fractures: a retrospective analysis.

The aim of the present study was to evaluate the outcomes in patients withsubcondylar fracture of mandible treated with 2 single miniplates compared to a 3-dimensional (3D) plate. This is a retrospective study which included patients diagnosed and treated for mandibular subcondylar fracture from January 2015 to December 2019. Included patients were divided into two groups, group 1: 2 miniplate group and group 2: 3D plate group. The data was obtained from the patients' records and evaluated for various outcomes including occlusal stability, postoperative complications like plate fracture, non-union, plate or screw loosening, and plate or screw infection leading to implant removal, wound dehiscence, salivary fistula, and facial nerve paralysis. The statistical analysis was performed using chi square test and Student's t test. A total 58 patients (43 males and 15 females) were enrolled in the two groups ranging from 21 to 59 years. A total of 35 patients were recruited in group 1, whereas 23 patients were recruited in group 2. There was no statistically significant difference in the two groups with regard to the age range, gender, diagnosis, side of fracture, and accompanying fractures. Occlusal instability, wound dehiscence, and facial nerve paralysis was found in both the groups. Group 1 had 1 patient which required implant removal due to screw loosing, whereas group 2 had 2 patients which required plate removal due to plate fracture. One patient in group 2 required second surgery for fixation of fracture due to non-union. One patient in group 1 developed a sialocele postoperatively. However, there was no statistically significant difference in any of the variables assessed among the two groups (p > 0.05). The results of our study indicate that the 2 miniplates and 3D plate system are effective in the management of mandibular subcondylar fractures.