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Objective: To evaluate the capacity of the automatic detection system to accurately grade, from smartphones' selfie pictures, the severity of seven new facial signs added to the nine previously integrated. Methods: A two‐step approach was conducted: first, to check on 112 Korean women, how the AI‐based automatic grading system may correlate with dermatological assessments, taken as reference; second, to confirm on 1140 women of three ancestries (African, Asian, and Caucasian) the relevance of the newly input facial signs. Results: The sixteen specific Asian facial signs, detected automatically, were found significantly (P <.0001) highly correlated with the clinical evaluations made by two Korean dermatologists (wrinkles: r =.90; sagging: r =.75‐.95; vascular: r =.85; pores: r =.60; pigmentation: r =.50‐.80). When applied at a larger scale on women of different ethnicities, new signs were found of good accuracy and reproducibility, albeit depending on ethnicity. Due to contrast with the innate skin complexion, the facial signs dealing with skin pigmentation were found of a much higher relevance among Asian women than African or Caucasian women. The automatic gradings were even found of a slightly higher accuracy than the clinical gradings. Conclusion: The previously used automatic grading system is now completed by adding new facial signs apt at being detected. The continuous development is now integrating some limitations with regard to the constitutive skin complexion of the self‐pictured subjects. Presenting reproducible assessments, highly correlated with medical grading, this system could change tremendously clinical researches, like in epidemiological studies, where it offers an easy, fast, affordable, and confidential approach in the objective quantification of facial signs. [ABSTRACT FROM AUTHOR]

The twist mechanism of the fiber strand in the condensing zone in compact spinning is complex. This paper proposes a dynamic model to evaluate the additional twist of the fiber strands. Based on the flow simulation in the condensing zone, the fiber trajectory in the suction slot was simulated and obtained. Several spinning parameters such as suction slot angle, suction slot width, negative pressure, and shape of suction slot, were varied to show their effects on the additional twist. The simulation results indicated that by increasing the suction slot angle from 5° to 10° the additional twist increased significantly. Higher negative pressure also leads to an increase in the additional twist. The suction slot width has a greater effect on the fiber trajectory than on the additional twist. An arc-shape suction slot increased the additional twist compared with a linear-shape one. An experimental test conducted revealed a precise agreement with the simulation results. [ABSTRACT FROM AUTHOR]

The modeling and simulation of the staple fiber spinning process is still a challenging concept in yarn technology due to the complexity of the process and uncontrollable parameters. This work presents a staple fiber yarn formation model based on the ideal assumptions about the configuration of the fibers and the cross-section of the sliver. The model presented utilizes a novel designed computer algorithm that randomly arranges staple fibers of defined length to simulate the typical arrangement of the fibers in a roving in the form of a fiber strand, which is then simulated in ABAQUS software to undergo the yarn formation stages, and the details are analyzed. The simulation results show the entire process of the twisting of the sliver and calculation of the configurational changes of each fiber in the strands is extracted. According to the model, the stages of the twisting of the sliver into the yarn are captured and presented, and the process of how the sliver converts to the yarn is analyzed in detail. In the real twisting experiment of the sliver, the propagation of the twist and the configurational changes of the fibers in the simulation experiment were verified. The experimental and numerical data are in good agreement and the model presents a precise mechanism for yarn formation. The work can be utilized to classify and understand fiber behavior during yarn processing, which can result in optimizing the staple fiber spinning technology. [ABSTRACT FROM AUTHOR]

The conventional rotor spinning unit generates flow vortices in the transfer channel upstream region which affect the fiber configuration and consequently yarn properties. Geometry and spinning parameters such as transfer channel length, inlet width, rotor outlet pressure, opening roller speed, and diameter were found to be key parameters influencing airflow characteristics. To reduce the flow vortices in the upper stream region, modifications of the transfer channel were proposed, and their airflow fields were analyzed using computational fluid dynamics. Three designs were studied: a round transfer channel inlet, a bypass channel for extra air supply, and one with both the bypass and the round inlet. Analysis of airflow revealed that the design with both round transfer channel inlet and a bypass proved to be very effective in properly directing the flow and minimizing vortices. The design was also characterized by smoother velocity streamlines and maximum mass flow across the transfer channel. A conventional rotor spinning unit was modified in which a round transfer channel inlet corner and a bypass channel were utilized to conduct the experimental tests. Three sets of yarn samples were produced using the conventional and modified rotor spinning units under different rotor speed conditions. Yarn properties were tested. Properties such as tenacity, CVm%, and thin and thick places of the spun yarns produced by the new design improved compared to that of the conventional yarn. [ABSTRACT FROM AUTHOR]

In order to regulate turbulence strength and determine airflow characteristics in a new dual-feed rotor spinning unit, the internal flow field is investigated. A computational fluid dynamics technique is employed to numerically study the three-dimensional model of the internal airflow in the new design. The effects of air velocity variation on turbulence strength, negative pressure, Re, and wall pressure distribution are investigated based on simulation data and previous studies. The results show that the turbulence strength and Re increased with increase in inlet air velocity. Pressure profiles inside the rotor varied significantly with positive pressure observed at the channel exits. Minimal inlet velocity maintains the flow field in the rotor interior below 100 m/s, which gives the ideal turbulence required to minimize yarn quality deterioration. The dual-feed rotor spinning unit showed more orderly streamline patterns with fewer vortices compared to the conventional one. The numerical simulation can provide insights on airflow studies and some guidelines for future prototyping and experiments to further improve the new design. [ABSTRACT FROM AUTHOR]

Here we present a solution-based method of growing three-dimensional flower-shaped metal halide perovskite crystals by drop casting solutions of FAxMA1−xPbyI1+2y precursors (FA = formamidinium, MA = methylammonium) on close-packed monolayers of titanium dioxide (TiO2) colloidal particles. The colloidal films directed perovskite crystallization during solvent evaporation, with crystals first nucleating within the confining interstitial sites between colloidal particles and growing perpendicular to the substrate surface. When growth proceeded above the colloidal film, the crystals blossomed outwards to form flower-shaped hopper crystals with a hierarchical 3D structure. The crystal shapes ranging from circular discs to pointed snowflakes were achieved by varying the solution pH and precursor composition. Structural complexity in these crystals was observed across multiple length scales – X-ray diffraction patterns and spatially-resolved photoluminescence mapping revealed three polymorphs present for all compositions tested: two bulk phases and one surface phase. These structures exhibit broad areas for light absorption but small contact areas with the underlying substrate for charge transport, which may be useful for optoelectronic devices, such as 2D photodetectors. [ABSTRACT FROM AUTHOR]

Considering the changes of ply yarn's structure parameters during the axial extension, a new model has been proposed for predicting the tensile curve of polyester twisted ply yarn under large deformation without the tensile strength tests. The relationships between the structural parameters and tensile properties under large deformation were considered. The feasibility and accuracy of the model were studied by comparing the predictive results and the experimental ones. The structural parameters in the model were acquired under every strain before rupture. The radial dimension and twist angle of the yarn were obtained by an observation platform and image processing technique. The true modulus of the yarn was obtained indirectly from the tensile data of the single yarn and the mathematical equations. The tensile curves of the yarns at different twist levels for predicting were plotted. The results demonstrated that the predicted curve tendency and the values were quite close to the experimental ones. The model exhibited a good applicability to predict the tensile curves for low and medium twist yarns. [ABSTRACT FROM AUTHOR]

It is considered that the strength of the ply yarn consisting of continuous filaments mainly depends on the properties of the single yarn and the cohesion forces among the single yarns, thus a mathematical model with relatively few parameters under given assumptions is established to predict the tensile strength of a two-ply yarn from single filament yarn. Relative relationships of the tensile force part and the interaction part are developed, respectively. The single yarn is tested to obtain fundamental data e.g. yarn strength and breaking elongation. After two strands of filament yarns are twisted into the ply yarns under different twist levels, the tensile strength, breaking elongation and structure parameters are measured or calculated for verifying the model later. Finally, the results show good agreement with the experimental values, and this model can be used to predict the performance of the finished strand yarns in actual productions. [ABSTRACT FROM AUTHOR]

With the increasingly accurate modeling and simulation demands and techniques, obtaining the knowledge of the multi-component phase equilibrium states holds the bottleneck challenge in the study of multi-phase fluid flow. In order to resolve the shortages in computational efficiency and stability in the conventional iterative flash calculation, a new phase equilibrium prediction method is proposed by solving the saddle point of the multi-phase system. In this paper, the HiSD (High-index saddle point dynamics) algorithm is used for the first time to calculate the saddle points on the energy landscape of the two-phase two-component NVT flash model based on the Peng-Robinson equation of state, and the up-down search algorithm of HiSD is applied to generate the solution landscape of the flash system. The Rosenbrock-Euler ETD (exponential time differencing) format is involved to reduce the interference of system rigidity to the calculation. It can be referred from the numerical analysis that there are at most the 1 s t -order saddle points in the energy landscape of the two-component two-phase NVT flash system, and all these saddle points are located on one straight line of the hyperplane, where the energy is equal everywhere. All these 1 s t -order saddle points can converge to the same or equivalent local minima, which indicates that the two-component two-phase flash system is a system with only one single solution with physical meanings. In addition, the saddle points also obey a linear relationship and the energy remains the same at different temperatures. Therefore, using the method proposed in this paper, the conventional two-step efforts of phase stability test and phase separation calculation can be simplified. The 1 s t -order saddle points of the system can be directly calculated, reducing the need for an initial guess. The local minima can be directly searched through the downward direction of the saddle point, which greatly reduces the calculation amount of phase equilibrium calculations. Furthermore, the minimum states at different temperatures can be calculated in batch by using one certain initial value, which significantly improves the adaptability and reliability for complex engineering problems with drastic temperature changes. • The HISD algorithm used for the first time in saddle point calculation in NVT flash. • The Rosenbrock-Euler ETD format used to reduce the interference of system rigidity. • At most the 1st-order saddle points in the energy landscape of the 2-component system. • There is only one solution in the 2-component 2-phase NVT flash problem. • All the 1st-order saddle points can converge to the equivalent local minima. [ABSTRACT FROM AUTHOR]

This article presents the use of quadratic general rotary unitized design method in optimization of spinning parameters of T-400/cotton core spun yarn on a ring frame. T-400 is a bicomponent filament based on sorona 3GT polymer form DuPont. An experimental design was generated using MINITAB©15 which included three factors and five levels. Three factors were the twist, filament draw ratio, and the spindle speed with respect to the yarn properties tested by Uster tester. The research draws clear application of quadratic general rotary unitized method on optimization, with step by step analysis of the variable factors in relation to responses. The optimum spinning parameters for hairiness, evenness, and tenacity while holding other yarn qualities as limiting factors were the following: twist value 430 TPM, filament draw ratio of 0.945, and the spindle speed of 7494 rpm. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluated the performance of multiparametric magnetic resonance imaging (MRI)–based fusion radiomics models (MMFRs) to predict telomerase reverse transcriptase (TERT) promoter mutation status and progression-free survival (PFS) in glioblastoma patients. Methods: We retrospectively analysed 208 glioblastoma patients from two hospitals. Quantitative imaging features were extracted from each patient's T1-weighted, T1-weighted contrast-enhanced, and T2-weighted preoperative images. Using a coarse-to-fine feature selection strategy, four radiomics signature models were constructed based on the three MRI sequences and their combination for TERT promoter mutation status and PFS; model performance was subsequently evaluated. Subgroup analyses were performed by the radiomics signature of TERT promoter mutation status and PFS to distinguish patients who could benefit from prolonged temozolomide chemotherapy cycles. Results: TERT promoter mutation status was best predicted by MMFR, with an area under the curve (AUC) of 0.816 and 0.812 for the training and internal validation sets, respectively. The external test set also achieved stable and optimal prediction results (AUC, 0.823). MMFR better predicted patient PFS compared with the single-sequence radiomics signature in the test set (C-index, 0.643 vs 0.561 vs 0.620 vs 0.628). Subgroup analyses showed that more than six cycles of postoperative temozolomide chemotherapy were associated with improved PFS for patients in class 2 (high TERT promoter mutation and high survival rates; HR, 0.222; 95% CI, 0.054 − 0.923; p = 0.025). Conclusion: MMFR is an effective method to predict TERT promoter mutations and PFS in patients with glioblastoma. Moreover, subgroup analysis could differentiate patients who may benefit from prolonged TMZ chemotherapy cycles. [ABSTRACT FROM AUTHOR]

• The role of polyvinylpyrrolidone in inducing mannitol crystals to twist is unclear. • Melt viscosity is not a primary factor in determining twisting intensity. • Steady torsional shear forces during crystallization can affect twisting intensity. Many molecular crystals grow as twisted lamellae from the melt when the driving force is high, but the mechanisms governing the spontaneous formation of helicoidal crystallites are varied and those operative in particular cases are difficult to identify. Polyvinylpyrrolidone (PVP) induces the crystallization of d -mannitol as banded spherulites comprised of twisted fibrils emanating radially from spherulite nucleation centers. The molecular weight of the PVP phase affects the twisting pitch, P , (rotation of the crystallite by 180°), in d -mannitol thin films crystallized from the melt. At a relatively high crystallization temperature (T c = 130 °C), P was sensitive to the PVP molecular weight, ranging from 390 ± 20 μm for d -mannitol films incorporating 15 wt% 10 kDa PVP to 20 ± 3 μm for the same weight of 1300 kDa PVP. Magnitudes of complex viscosities, η ∗ , of d -mannitol/PVP melts measured via small-amplitude oscillatory shearing were strongly dependent on the PVP molecular weight, but were not correlated to P (T). Instead, P was sensitive to the dynamic PVP chain conformation during d - mannitol crystallization. Under steady torsional shear, P decreased from ∼ 30 μm to ∼ 8 μm with increasing shear rates from 0.01 to 100 s−1 for d -mannitol films crystallized at 130 °C in the presence of 15 wt% 10 or 1300 kDa PVP. Shear forces decrease the entanglement density of polymer chains while orienting the chains along the stream lines of the viscometric flow, indicating that the conformations of macromolecular additives can affect the pitch of banded spherulites. By contrast, P in d -mannitol twisted by d -sorbitol was independent of shear rate. [ABSTRACT FROM AUTHOR]

The axisymmetric electrokinetic flows are of great importance in Micro-Electro-Mechanical System (MEMS). In this paper, the Nernst–Planck (NP) model under the cylindrical coordinate system is used to describe the axisymmetric electrokinetic flows. Furthermore, a coupled lattice Boltzmann method (LBM) is proposed to solve the axisymmetric NP model. To validate the capacity of the proposed coupled LBM, the axisymmetric electrokinetic flows in circular tubes and annular ducts are numerically studied. The numerical results agree well with the reported numerical data. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanohybrids GPM with different GO content were synthesized via one-step hydrothermal method. • GPM improved the fire safety of EP with significantly reducing the PHRR, THR, PCOP and TSP with only 3 wt% loading. • Excellent fire safety of EP/GPM attributed to the comprehensive synergistic effect of Mg(OH) 2 and GO. • GPM exhibited superior mechanical properties compared to that of Mg(OH) 2. With the rapid development of Graphene based hybrid materials, various of them were fabricated to improve the fire safety of EP. However, the effect of GO content in the hybrid material on flame retardancy of EP composites is rarely reported. In order to find the optimal ratio of GO/Mg(OH) 2 , platelet-like Mg(OH) 2 functioned graphene (GPM) were synthesized with diverse content GO substance and then presented into EP resin for improving its fire retardancy. Various characterizations confirmed its composition, structure and morphology. The incorporation of GPM contains about 1% GO increased the tensile strength by 31.6% compared to that of untreated Mg(OH) 2. The GPM contains about 5% GO exhibited the finest fire safety in various EP composites. The fire-retardant assessments illustrated that the limiting oxygen index (LOI) of EP composite with 3 wt% GPM progressed to 27.8% compared with virgin EP (24.4%). In parallel, compared to virgin EP, the peak heat release rate, peak smoke production rate, total smoke production and peak CO production rate of EP/5GPM were diminished by 50.9%, 44.0 %, 25.5% and 53.1%, separately. The mechanism investigation revealed that the prominent flame retardancy and smoke suppression were attributed to the physical barrier of GO, the endothermic decomposition of Mg(OH) 2 , the barrier effect of MgO and synergistic effect between GO and Mg(OH) 2 toward the optimized carbonization. In perspective, hierarchical platelet structure with synergistic effect offered an effective approach for the fire-safe polymer. [ABSTRACT FROM AUTHOR]

Inspired by the structure of corn, a NiFe Prussian blue analogue nanocages decorated magnesium hydroxide composite was synthesized for the first time using magnesium hydroxide rods (RMH) as the "corn cob", a Prussian blue analogue (PBA) as the "corn kernels" and polydopamine (PDA) as the membrane linking RMH and PBA. Subsequently, the RMH@PDA@PBA composite was introduced into epoxy resin (EP) to improve its fire retardancy and mechanical properties. The composition, structure and morphology of the RMH@PDA@PBA-incorporated EP composite were investigated. The tensile strength of EP with 3 wt.% RMH@PDA@PBA reached 41.77 MPa, which is higher than that of neat EP (40.51 MPa). The fire-retardant assessments illustrated that the limiting oxygen index and vertical burning tests (UL-94) of EP composite with 3 wt.% RMH@PDA@PBA progressed to 32.3% and the V-0 level as compared to those of virgin EP (24.4% and no rating). In addition, as compared to virgin EP, the peak heat release rate, peak smoke production rate, total heat release at 200 s and total smoke production at 200 s of EP/3RMH@PDA@PBA decreased by 43.1%, 50.0%, 43.9% and 56.3%, respectively. The investigation of the underlying mechanism revealed that the flame retardancy and smoke suppression of EP/3RMH@PDA@PBA were attributed to the endothermic decomposition of RMH, "gauze barrier" mechanism of MgO/FeO, catalytic charring effect of Fe derivatives (MgO/FeO, FeNi 3 , Fe 5 C 2 , Fe 2 N, etc.) and free radical scavenging effect of PBA@Fe[Ⅲ]. Thus, this study on bio-inspired hierarchical nanostructures paves a new pathway for the efficient production of fire-safe polymers. [Display omitted] • A novel low-cost RMH@PDA@PBA with corn structure was first prepared. • The RMH@PDA@PBA significantly improves the fire safety of epoxy resin. • 3 wt.% RMH@PDA@PBA endowed epoxy resin with UL-94 V-0 and reduced smoke production. • The addition of RMH@PDA@PBA enhanced the mechanical properties of epoxy resin. [ABSTRACT FROM AUTHOR]