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Abstract Current tools for predicting survival outcomes in colon cancer patients predominantly rely on clinical and pathologic characteristics. However, accumulating evidence demonstrates a significant correlation between nutritional status and patient outcomes. This study aimed to establish a new dynamic nomogram for individualized prediction of postoperative overall survival (OS). The clinicopathological and nutritional data of colon cancer patients undergoing radical resection were retrospectively collected and randomly divided into the primary and validation cohorts. Risk factors on OS rates were investigated by Cox analyses and, the nomogram was constructed using significant predictors. Among 1,024 patients, 341 deaths were observed after median follow-up of 54 months. Five independent prognostic factors, including nutritional status assessments, were incorporated into the nomogram. The C-index regarding 1-, 3-, and 5-year OS were 0.830, 0.859, and 0.757 in the primary cohort and 0.843, 0.870, and 0.773 in the validation cohort, respectively. Calibration curves for the probability of OS exhibited an optimal agreement. Decision curve analyses revealed the greater application value of the nomogram than the TNM staging system. Based on the nomogram, patients could be stratified into three scenarios with significant prognostic classification (P

With the rapid development of the new energy sector and lithium-ion (Li-ion) battery technologies, using Li-ion batteries with high energy density and high discharge rate to form the primary energy subsystem can further improve the compactness and miniaturization level of pulsed power systems. In traditional electric power systems, Li-ion batteries normally operate under the discharge condition of low current and long time. However, as the main power source of pulsed power systems, it is required that Li-ion batteries should have the capability for high-rate pulse discharge. To ensure the safe and reliable operation of the battery energy storage system, it is necessary to conduct the parameter identification of the Li-ion battery model to establish an accurate pulse discharge model under such working conditions. This paper focuses on the discharge characteristics of a cylindrical high-rate single Li-ion battery with a capacity of 3 Ah. At a 20 C rate, the discharge data were obtained when the pulse repetition frequency was 10 Hz and the duty cycle was 90%. By using the mathematical expressions of the Thevenin equivalent circuit model, the recursive relationship of the circuit parameters was obtained, and the parameter identification of the battery model was conducted based on the experimental data by using the genetic algorithm. The results show that the fitting accuracy of the parameter identification reaches 0.9995, indicating the high precision of the model for the Li-ion battery. This work provides a significant reference for the modeling and parameter identification of Li-ion batteries under high-rate pulse discharge conditions.

Abstract Developing advanced engineering polymers that combine high strength and toughness represents not only a necessary path to excellence but also a major technical challenge. Here for the first time a rigid‐flexible interlocking polymer (RFIP) is reported featuring remarkable mechanical properties, consisting of flexible polyurethane (PU) and rigid polyimide (PI) chains cleverly woven together around the copper(I) ions center. By rationally weaving PI, PU chains, and copper(I) ions, RFIP exhibits ultra‐high strength (twice that of unwoven polymers, 91.4 ± 3.3 MPa), toughness (448.0 ± 14.2 MJ m−3), fatigue resistance (recoverable after 10 000 cyclic stretches), and shape memory properties. Simulation results and characterization analysis together support the correlation between microstructure and macroscopic features, confirming the greater cohesive energy of the interwoven network and providing insights into strengthening toughening mechanisms. The essence of weaving on the atomic and molecular levels is fused to obtain brilliant and valuable mechanical properties, opening new perspectives in designing robust and stable polymers.

The improvement in the reliability and lifespan of insulated gate bipolar transistor (IGBT) devices and the enhancement of system efficiency under high-frequency pulse conditions are receiving increasingly wide attention, and all of these are closely related to the evaluation of the power loss of the IGBT. The traditional method for assessing the power loss of the IGBT is through curve fitting of the dual-pulse experimental results, without delving into the conduction process of the IGBT and without considering the IGBT model itself and the parasitic parameters present in the test circuit. In response to the condition of a pulse duration of 100 ns for IGBT single devices, a universal test circuit has been designed to measure the collector-emitter voltage waveform and the collector current waveform. A method based on Computer Simulation Technology for field-circuit co-simulation to evaluate the power loss of the IGBT has been proposed, which takes into account the parasitic parameters in the actual circuit. In this method, the 3D model of the IGBT device, as well as the circuit model of the test circuit, is established. The power loss curve of the IGBT was obtained from the evaluation model, and the results agree well with the power loss curve obtained from experiments. This method provides guidance for seeking lower power loss in order to improve the reliability and lifespan of the IGBT, as well as enhance system efficiency. It also provides theoretical guidance for further research on the thermal damage mechanism of the IGBT.

With the wide application of the Internet of Things (IoT), storing large amounts of IoT data and protecting data privacy has become a meaningful issue. In general, the access control mechanism is used to prevent illegal users from accessing private data. However, traditional data access control schemes face some non-ignorable problems, such as only supporting coarse-grained access control, the risk of centralization, and high trust issues. In this paper, an attribute-based data access control scheme using blockchain technology is proposed. To address these problems, attribute-based encryption (ABE) has become a promising solution for encrypted data access control. Firstly, we utilize blockchain technology to construct a decentralized access control scheme, which can grant data access with transparency and traceability. Furthermore, our scheme also guarantees the privacy of policies and attributes on the blockchain network. Secondly, we optimize an ABE scheme, which makes the size of system parameters smaller and improves the efficiency of algorithms. These optimizations enable our proposed scheme supports large attribute universe requirements in IoT environments. Thirdly, to prohibit attribute impersonation and attribute replay attacks, we design a challenge-response mechanism to verify the ownership of attributes. Finally, we evaluate the security and performance of the scheme. And comparisons with other related schemes show the advantages of our proposed scheme. Compared to existing schemes, our scheme has more comprehensive advantages, such as supporting a large universe, full security, expressive policy, and policy hiding.

ObjectiveHandgrip strength (HGS) and the high-sensitivity modified Glasgow prognostic score (HS-mGPS) are associated with the survival of patients with cancer. However, no studies have investigated the combined effect of HGS and HS-mGPS on the overall survival (OS) of patients with colon cancer.MethodsProspective follow-up data of colon cancer patients undergoing radical resection from April, 2016 to September, 2019 were retrospectively collected. We combined the HGS and HS-mGPS to create a new composite index, HGS-HS-mGPS. The hazard ratio (HR) and 95% confidence interval (CI) were calculated using Cox regression models to assess the association between variables and OS. Risk factors on OS rates were investigated by Cox analyses and the nomogram was constructed using significant predictors and HGS-HS-mGPS. The predictive performance of the nomogram was evaluated by receiver operating characteristic curve and calibration curve.ResultsThis study included a total of 811 patients, of which 446 (55.0%) were male. The HGS optimal cut-off values of male and female patients were 28.8 and 19.72 kg, respectively. Multivariate analysis revealed that low HGS and high HS-mGPS were independent risk factors of colon cancer after adjusting confounders (adjusted HR = 3.20; 95% CI: 2.27–4.50; p

Abstract Recyclability of thermosetting polymers and their composites is a challenge for alleviating environmental pollution and resource waste. In this study, solvent-recyclable thermosetting polyimide (PI) and its composite were successfully synthesized. The tensile strength, elongation at break, and Young’s modulus of PI are 108.70 ± 7.29 MPa, 19.35% ± 3.89%, and 2336.42 ± 128.00 MPa, respectively. The addition of reduced graphene oxide (RGO) not only enhances the mechanical properties of PI but also endows it with excellent tribological properties. The PI illustrates a high recycling efficiency of 94.15%, but the recycled composite exhibits inferior mechanical properties. The recycling and utilization of PI and its composite are realized through imine bonds (–C=N), which provides new guidance for solving the problem of environmental pollution and resource waste and is potential application in the field of sustainable tribology.

Abstract Self-healing and recyclable polymer materials are being developed through extensive investigations on noncovalent bond interactions. However, they typically exhibit inferior mechanical properties. Therefore, the present study is aimed at synthesizing a polyurethane–urea elastomer with excellent mechanical properties and shape-memory-assisted self-healing behavior. In particular, the introduction of coordination and hydrogen bonds into elastomer leads to the optimal elastomer exhibiting good mechanical properties (strength, 76.37 MPa; elongation at break, 839.10%; toughness, 308.63 MJ m−3) owing to the phased energy dissipation mechanism involving various supramolecular interactions. The elastomer also demonstrates shape-memory properties, whereby the shape recovery force that brings damaged surfaces closer and facilitates self-healing. Surprisingly, all specimens exhibite clustering-triggered emission, with cyan fluorescence is observed under ultraviolet light. The strategy reported herein for developing multifunctional materials with good mechanical properties can be leveraged to yield stimulus-responsive polymers and smart seals.

Source and mask optimization is a critical technique for further resolution enhancement in immersion lithography systems, wherein the optimal illumination source shape is widely generated by the micromirror array. Accordingly, the accurate achievement of the allocated angles of micromirrors is a key prerequisite for the implementation of arbitrary illumination patterns. In this paper, we propose an angle monitor to ensure the high-precision tilting of thousands of biaxial micromirrors. As one of the critical modules for closed-loop control of the two-dimensional micromirror array, the online monitor feeds the monitored high-precision tilt angle back to the processing system. The angle monitor mainly consists of the spot scanning module and the angle detection module. Among them, an f-θ lens and a Fourier transform lens with satisfied performances are designed and evaluated by CODE V. Furthermore, a galvanometer and the designed f-θ lens are adopted for the generation of the spot array irradiated on the electrostatic actuated mirrors. Meanwhile, the designed Fourier transform lenses are employed to detect the corresponding tilt angles. In addition, the performance of the proposed system is identified by simulations and experiments individually. It is demonstrated that the monitorable biaxial tilt range of the system is (−2.5°, +2.5°) with a repeatability of better than 0.005°. The large-format micromirror array can be monitored completely without optical cross-talk. Through the device, a 16 × 16 micromirror array is monitored, where the initial angle with no bias voltage applied is captured and the voltage–angle relation for individual micromirrors is obtained. In general, the proposed system can be utilized in the illumination system, providing an efficient and reliable method for complex source shape generation.

Thermoset shape memory polyimides (TPIs) are widely used in the fields of high-temperature smart devices. However, the recent molding of polyimides limits most of potentials in the form of two-dimensional film. In this work, we synthesized a novel shape memory polyimide (SMPI) ink that could be used for both Digital Light Process and extrusion molding 3D printing. Through UV-induced free radical polymerization, 3D custom polyimides ink can be cured rapidly. Remarkably, the 3D printed PI exhibits excellent shape memory performance, with Rf of 99.8%, Rr of 98.3%, therefore the 4D printing PI was successfully prepared. The 3D printed airplane, ultrasonic motor and pagoda can actively recover the film folding, expanding combined compressing, and vertical distorting to their permanent shape, which presents the outstanding 4D printing properties. Moreover, SMPI can be used in extrusion molding to print films, the residual stress induced the self-folding and then a vector model was applied to characterize transformation of extruded plates. In order to develop the application diversity of extruded 4D polyimide, self-folding box and stimuli-response gripper are designed, the gripper is able to pull up steel ball 15 times heavier than itself. Thus, SMPI will be benefit to expand the applied scope of SMPI.

Herein, graphite/Fe3O4/resin-based composite absorbers are prepared by selective laser sintering (SLS) and vacuum impregnation of epoxy resin. The effects of different graphite-Fe3O4 powder compositions on the absorbing and mechanical properties of the composites are investigated. The results show that with the increase of Fe3O4 content, the absorption performance of the composites first increases and then decreases, and the absorption peak gradually moves from high frequency (12-18 GHz) to low frequency (2-8 GHz). The bending strength of composites decreases with the increasing of Fe3O4 content. When the mass ratio of graphite-Fe3O4 is 4:3, the wave absorption performance is the best, the minimum reflection loss is -54.8 dB, the effective absorption bandwidth is 2.8 GHz (8.72-11.52 GHz), and the bending strength is 11 MPa, which is 9 times higher than that of SLS plain billets. This is because the increase of the Fe3O4 content in the hybrid powder increases the number of heterogeneous interfaces, but decreases the number of holes inside the composite, which affects the number of microwave reflections inside the material, resulting in different wave absorption and mechanical properties. The graphite/ferrite/resin matrix composites prepared by SLS technology achieve the synergy of lightweight, high strength, and good wave absorption properties. [ABSTRACT FROM AUTHOR]

The uniform electron gas and the hydrogen atom play fundamental roles in condensed matter physics and quantum chemistry. The former has an infinite number of electrons uniformly distributed over the neutralizing positively charged background, and the latter only one electron bound to the proton. The uniform electron gas was used to derive the local spin density approximation to the exchangecorrelation functional that undergirds the development of the Kohn-Sham density functional theory. We show here that the ground-state exchange-correlation energies of the hydrogen atom and many other 1- and 2-electron systems are modeled surprisingly well by a different local spin density approximation (LSDA0). LSDA0 is constructed to satisfy exact constraints but agrees surprisingly well with the exact results for a uniform two-electron density in a finite, curved three-dimensional space. We also apply LSDA0 to excited or noded 1-electron densities, where it works less well. Furthermore, we show that the localization of the exact exchange hole for a 1- or 2-electron ground state can be measured by the ratio of the exact exchange energy to its optimal lower bound. [ABSTRACT FROM AUTHOR]

Background: miRNAs have been proved to function as diagnostic biomarkers. Extracellular vesicles (EVs) are carriers of miRNAs. This study aimed to investigate the diagnostic potential of miR-1 in plasma and extracellular vesicles (EVs) for patients with colorectal cancer (CRC). Methods: Bioinformatics analysis was used to find a target miRNA and its potential functions. miR-1 was then detected in plasma and EV from 49 control samples and 40 CRC samples. Next, the diagnostic potential of plasma and EV miR-1 were compared based on common biomarkers including CEA and CA211. Results: miR-1 was differentially expressed in CRC. Target gene and function analyses showed that it might participate in cell migration and the regulation of mRNA splicing via the spliceosome. Plasma miR-1 levels in CRC samples were significantly higher than those in control samples, whereas EV miR-1 levels were not statistically different. Based on receiver operating characteristic (ROC) curve analysis, comparing their predictive power compared to that of CEA and CA211, plasma miR-1 performed better and EV miR-1 performed worse. Conclusions: Our data indicate that plasma miR-1, but not EV miR-1, could function as a potential biomarker for CRC diagnosis. [ABSTRACT FROM AUTHOR]

The fundamental energy gap of a periodic solid distinguishes insulators from metals and characterizes low-energy single-electron excitations. However, the gap in the band structure of the exact multiplicative Kohn-Sham (KS) potential substantially underestimates the fundamental gap, a major limitation of KS densityfunctional theory. Here, we give a simple proof of a theorem: In generalized KS theory (GKS), the band gap of an extended system equals the fundamental gap for the approximate functional if the GKS potential operator is continuous and the density change is delocalized when an electron or hole is added. Our theorem explains how GKS band gaps from metageneralized gradient approximations (meta-GGAs) and hybrid functionals can be more realistic than those from GGAs or even from the exact KS potential. The theorem also follows from earlier work. The band edges in the GKS one-electron spectrum are also related to measurable energies. A linear chain of hydrogen molecules, solid aluminum arsenide, and solid argon provide numerical illustrations. [ABSTRACT FROM AUTHOR]