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Polyimide (PI) refers to a type of high-performance polymer containing imide rings in the main chain, which has been widely used in fields of aerospace, microelectronic and photonic devices, gas separation technology, and so on. However, traditional aromatic PIs are, in general, the inefficient fluorescence or even no fluorescence, due to the strong inter- and intramolecular charge transfer (CT) interactions causing unavoidable fluorescence quenching, which greatly restricts their applications as light-emitting functional layers in the fabrication of organic light-emitting diode (OLED) devices. As such, the development of fluorescent PIs with high fluorescence quantum efficiency for their application fields in the OLED is an important research direction in the near future. In this review, we provide a comprehensive overview of fluorescent PIs as well as the methods to improve the fluorescence quantum efficiency of PIs. It is anticipated that this review will serve as a valuable reference and offer guidance for the design and development of fluorescent PIs with high fluorescence quantum efficiency, ultimately fostering further progress in OLED research. [ABSTRACT FROM AUTHOR]

Using finite element simulation and single-variable experimental methods, this study analyzes the variations in the microstructure and hardness of a 304 stainless steel wire during Joule heating fused filament fabrication. The effects of current intensity, printing speed, and roller pressure on the macroscopic morphology, microstructure, and microhardness of a single-layer single-channel formation were investigated. The results indicate that when the current intensity is 400 A, the printing speed is 1000 mm/min, and the roller pressure is 0.3 N, the surface of the single-layer single-channel formation is smooth and exhibits optimal forming characteristics with a width-to-height ratio of 3.23, a dilution rate of 51.61%, and an average microhardness of 238.17 HV. As the current intensity increases, the microstructure in the fusion zone initially decreases in size and then increases; similarly, with the increase in printing speed, the microstructure in the fusion zone first decreases and then increases; as the roller pressure increases, the microstructure in the fusion zone initially increases in size and then decreases. The microhardness initially increases and then decreases with the increase in process parameters, resulting in uneven hardness distribution due to the variations in microstructure size. The optimal combination of process parameters achieves a balance between heat input, cooling rate, and growth rate, thereby achieving grain refinement and hardness improvement, ultimately enhancing the mechanical properties of the material. [ABSTRACT FROM AUTHOR]

Purpose: To study the relationship between LARS1 expression and immune infiltration and prognosis in hepatocellular carcinoma (HCC). Patients and Methods: The clinical characteristics together with LARS1 expression levels were obtained from the TCGA database. Immunohistochemistry confirmed LARS1 expression levels in paraneoplastic and tumor tissues. To investigate LARS1-related downstream molecules, a network of protein-protein interactions (PPIs) and the Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) were built. Furthermore, gene set enrichment analysis (GSEA) was used to analyze the pathways associated with LARS1 expression, whereas Single-sample GSEA (ssGSEA) was applied to perform an association study between immune infiltration and LARS1 gene expression. The TISCH Database and the TISIDB database were used to compare the difference of LARS1 expression in hepatocellular carcinoma and immunomodulators. Results: In comparison to that in normal tissues, the LARS1 expression level was elevated in tumor tissues. LARS1 expression exhibited substantial correlation with AFP, Histologic grade, pathologic stage, Residual tumor, and Vascular invasion in HCC. Higher LARS1 expression in HCC was linked to lower progression-free survival (PFS), disease-specific survival (DSS), and overall survival (OS). According to the GO/KEGG study, the important biological process (neutral lipid metabolic process), cellular component (triglyceride-rich plasma lipoprotein), molecular functions (lipase inhibitor activity), and KEGG pathway (cholesterol metabolism) could be a probable function mechanism in promoting HCC. Various pathways as per GSEA revealed that they were enriched in samples with elevated LARS1 expression. The expression level of LARS1 in malignant tumor cells after immunotherapy was significantly higher than that before immunotherapy. LARS1 was also remarkably linked to the infiltration level and the immunomodulators. Conclusion: LARS1 can be used as a biomarker of HCC, which is associated to immune infiltration of HCC. [ABSTRACT FROM AUTHOR]

Perylene dianhydride (PDA), a low-cost, readily available, and chemically stable organic cathode material, has received extensive attention in recent years. However, its large π planar structure often results in poor or difficult-to-control micro-nanostructures during conventional electrode processing methods, such as dry mixing. This leads to limited cycling life and rate performance. Here, we present a simple electrospinning strategy for controlling the micro-nanostructures of electrodes based on PDA, carbon black Super P (SP), and polyvinylidene fluoride (PVDF) composites. The spinnable PVDF polymer not only provides the micro-nanofibrous structure but also realizes the function of the binder in the electrodes, offering the hierarchical micro-nanostructures of the electrospun PDA (PDA-es) electrodes. The unique structure enables PDA-es electrodes to possess rapid charge transport properties and ultrafast reaction kinetics. Specifically, the PDA electrode based on high molecular weight electrospun PVDF (PDA-es-H) demonstrates a high initial specific capacity (126.2 mA h g−1), robust cycling stability (∼95% and ∼60% capacity retention after 100 cycles at 50 mA h g−1 and 1000 cycles at 100 mA h g−1, respectively), and excellent rate performance. This study provides a straightforward and efficient strategy for realizing the micro-nanostructures of organic electrodes for high-performance lithium-organic batteries. [ABSTRACT FROM AUTHOR]

An in situ gel separator based on an electrospun three-layer nanofibrous membrane (PSE11-Gel) is developed for high-performance lithium-organic batteries (LOBs). The highly efficient shuttle effect inhibition of organic cathode molecules or lithiated intermediates has been demonstrated for PSE11-Gel to realize high-capacity stable LOBs. [ABSTRACT FROM AUTHOR]

In this study, a solution to the issue of a large heat-affected zone in Wire Arc Additive Manufacturing is presented by employing the Joule Heat Additive Manufacturing method to create a single layer and single channel with a reduced heat-affected zone. The microstructure of the single layer and single channel is thoroughly investigated using various detection methods, including optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and electron backscatter diffraction (EBSD). The results reveal that the heat-affected zone formed by the Joule Heat Additive Manufacturing method is smaller than that produced by the Wire Arc Additive Manufacturing method. Additionally, the grains in the single layer and single channel progress from planar to columnar, then equiaxed, and finally back to columnar from the fusion line to the top of the wire. The element content and distribution are relatively uniform. The microstructure of the single layer consists of austenite and a small amount of ferrite, with austenite accounting for 99.71% of the content. The grain size in the middle of the wire is mainly around 10 μm, with the smallest angle grain boundaries within 10°. The distribution of local grain orientation differences in the three regions is found to be largely consistent. The analysis of the microstructure of the single layer and single channel serves as a valuable reference for understanding the behavior of single-channel multi-layers in future studies. [ABSTRACT FROM AUTHOR]

To change the situation of shape memory polymers (SMPs) that can only remember very few shapes and enable discretional morphing for practical application, the authors report a reversible stepless multiple SMP derived from ultrahigh molecular weight polyethylene (UHMWPE). As the crystals of semi‐crystalline polymers are assembled by those with slightly different melting temperatures, and each type of crystal can remember a single shape, the crystalline region of UHMWPE is allowed to remember plenty of temporary shapes after programming. Changing the temperature of the programmed polymer within the melting/crystallization temperature ranges would lead to releasing/recovery of the memorized temporary shapes. Accordingly, multiple shape memory effects can be easily realized without an elaborate design of material structure and training process in advance as before. The temperature‐dependent adjustability of the analog capacitor and soft lens with embedded programmed UHMWPE as actuators, characterized by the continuous/random/proportional responsivity, further reveals the utilization prospects of the controllable reversible stepless discretionary morphing effect. Moreover, the maximum work density of the programmed UHMWPE is found to be 210 kJ/m3, which is more than 10 times of piezoelectric ceramics, so that it can serve as a proof‐of‐concept mechanical driver for reversibly pumping of ethanediol‐droplet upon heating/cooling. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) constitutes a major global health threat due to the high incidence and mortality. Sorafenib is known as the first-line medication for advanced HCC; however, it only extends the limited benefit for HCC patients as the development of acquired resistance. Withaferin A exerts broad pharmaceutical applications in several cancers. However, its effects on HCC cell metastatic potential and sorafenib resistance remain elusive. Here, we corroborated that Withaferin A greatly restrained cell viability, invasion, vasculogenic mimicry (VM) formation, and VE-cadherin levels in HepG2 and SNU449 cells. Moreover, Withaferin A sensitized sorafenib (SR)-resistant HCC cells to sorafenib. In striking contrast to the parental cells, lower ferroptosis was observed in SR-resistant cells as the lower ROS, MDA, and higher intracellular GSH levels in SR-resistant cells. Of interest, Withaferin A enhanced ferroptosis in SR-resistant cells, which was reversed by ferroptosis antagonist liproxstation-1. Notably, Withaferin A elevated Keap1 expression to mitigate Nrf2 signaling activation-mediated epithelial to mesenchymal transition (EMT) and ferroptosis-related protein xCT expression. Importantly, blockage of the Keap1/Nrf2 signaling overturned Withaferin A-evoked ferroptosis and facilitated sorafenib resistance. In addition, knockdown of Keap1 antagonized the inhibitory efficacy of Withaferin A on HCC cell viability, invasion, and VM formation. Consequently, Withaferin A may attenuate the metastatic potential and sorafenib resistance by regulating Keap1/Nrf2-associated EMT and ferroptosis. Thus, Withaferin A may serve as a promising agent for HCC therapy, especially for advanced HCC. [ABSTRACT FROM AUTHOR]

A temporary plugging agent is an effective tool for increasing production in old wells. By considering the temporary plugging materials used in the remote WY area, three concentrations and five ratios under different fracture widths were designed and optimized. Thus, the fracture diversion under true triaxial stress was studied. The results showed that when the fracture widths were 2.0, 4.0, and 6.0 mm, the corresponding optimal plugging scheme was that the concentrations of the temporary plugging agent were 12.0, 18.0, and 18.0 kg/m3 and the ratios of 20–70 mesh to 200–300 mesh temporary plugging agent were 4:1, 2:1 and 4:1, respectively. When maintaining the same horizontal stress, an increase in the axial stress was accompanied by an increase in the fracture pressure; the initial fractures almost propagated along the direction of the horizontal maximum principal stress, but the shapes of the turning fractures were different. When the axial stress was the same, an increase in the horizontal stress difference was accompanied by a decrease in the corresponding fracture pressure and a gradual decrease in the degree of fracture turning. This study provides a basis for numerical simulation and field application of temporary plugging fracturing at fracture ends. [ABSTRACT FROM AUTHOR]

Radiation protective materials are widely applied to avoid occupational hazards from either particle emissions or high-energy electromagnetic waves. Herein, we present a boron imidazolate framework (BIF) as a novel neutron shielding additive with high neutron capture cross-section elements B/Li and H. The BIF1-based epoxy resin matrix (Ep-BIF1) possesses high thermal stability and excellent resistance capacity. The neutron radiation shielding property was characterized using an Am–Be source, in which the thermal neutron shielding efficiency of Ep-BIF1 is notably higher than that of Ep-B4C with equal boron concentration, showing potential applications as an advanced efficient neutron radiation shielding composite. [ABSTRACT FROM AUTHOR]

Recently, the siamese convolutional neural network plays an important role in the field of visual tracking, which can obtain high tracking accuracy and good real-time performance. However, the requirement of offline training a specific neural network results in the hardware source and time consumption. In order to improve the tracking efficiency and save computation resources, we adopt pre-trained densely connected neural network to extract robust target features. Since the pre-trained model is mainly used for classification task, it is not appropriate to directly adopt these deep features for visual tracking. We design a regression network to measure the importance of each channel to the target, and then propose a weighting fusion strategy to select the suitable features for visual tracking. Besides, we provide deep analysis about the proposed channel weighting method to demonstrate the superiority of this method through visualization of feature heatmaps. Extensive experiments on four classical benckmarks show that compared with state-of-the-art methods, our algorithm achieves the best results on several standard indicators and comparable results on other indicators. [ABSTRACT FROM AUTHOR]

Background: Advanced liver fibrosis can lead to cirrhosis, portal hypertension and liver failure. Besides, advanced liver fibrosis and cirrhosis are the major risk factors for hepatocellular carcinoma (HCC). Almost all patients with HCC also have liver cirrhosis. This study aims to predict the survival rate of hepatitis B-related hepatocellular carcinoma (HCC) by age, international standardized ratio, albumin and γ-glutamyl transpeptidase (AIAG), an indicator measuring the degree of cirrhosis. Methods: A total of 501 hepatitis B-related HCC patients experiencing radical surgery were analyzed, retrospectively. General data about demographics and labs were collected at the date of diagnosis to calculate AIAG [age, international standardized ratio (INR), albumin and gamma-glutamyl transferase (GGT)]. The Kaplan–Meier curves and Cox analysis were used to evaluate overall survival (OS) and recurrence-free survival (RFS). The C-index was calculated in R software (version 4.0.3) to evaluate the accuracy of the prognostic model. Results: During a median follow-up period of 30 months, 31.1% (156/501) of the patients died, and 34.3% (172/501) experienced the recurrence of HCC. Compared with patients with lower AIAG score, patients with higher AIAG score had higher Child-Pugh grade and were at higher Barcelona Clinic Liver Cancer (BCLC) stage (both P< 0.05). Multivariate analysis suggested that GGT, alpha fetoprotein (AFP), tumor size, BCLC stage and AIAG grade were independent predictors of OS and RFS. Furthermore, the combined use of tumor size, AFP and AIAG stage could predict survival significantly better (C-index=0.710, 95% CI: 0.669– 0.751) than BCLC stage. Conclusion: AIAG is significantly associated with survival of HCC patients, and provides additional prognostic information for patients with HCC. Our findings suggest that the combination of AIAG, tumor size and AFP stage has a better predictive value for the prognosis of patients with hepatitis B-related hepatocellular carcinoma. However, it is necessary for more external evidences to determine clinical utility. [ABSTRACT FROM AUTHOR]

Helical structures are attracting increasing attention owing to their unique typical physical and chemical properties. However, it remains a challenge to construct atypical helical structures at the microscale. This paper proposes a continuous spinning method with a microfluidic-chip-based spinning device to engineer atypical helical microfibers. The strategy causes polymer fluid to form the biomimetic Bulbine torta (BT)-like shape with the aid of the inhomogeneous viscosity rope-coil effect. In particular, the structure parameter of the BT microfibers could be optimized through the synchronous regulation of the microfluidic flow and reaction kinetics, and the obtained microfibers exhibit ultrahigh strain sensitivity, indicating great promise as exceptional candidates for constructing ideal strain sensors. In addition, single- and double-hollow BT microfibers are also prepared by introducing the core flow channel into the microfluidic chip and demonstrate high structural similarity to irregular blood vessels (e.g. varicose veins), which is promising for the actual application of blood vessel tissue engineering. [ABSTRACT FROM AUTHOR]

Effectively guiding and accurately controlling cell adhesion and growth on the surfaces of specific morphological materials are key issues and hot research topics for optimizing biomaterials. Herein, novel polymorphic alginate microfibers formed through microfluidic spinning technology in a single microchip are presented. Through programming the flow and reaction kinetics in microchannels, other than self-modified micromorphic channel geometry, polymorphic microfibers with precisely tuned curvature-adjustable morphology can be obtained. Finite element (FE) simulations of the flow field (unidirectional fluid–solid coupling) proved the efficacy of the proposed control strategy. Moreover, the specific disordered–ordered cell arrangements showed a linear relationship between bioinspired alginate microfibers with different curvatures and the orientation angle of L929 cells, and diversified growth morphologies, including oblate ellipse, star, tree and strip shapes, occurred on the customizable interface curvature of the calcium alginate microfibers, providing a paradigm for using specific structured natural biomedical materials for cell regulation. This work represents a new design concept for manufacturing polymorphic fibrous biomedical materials through a unique marriage of the fields of green chemistry, hydromechanics, and biomaterials, which should be very useful for guiding the controllable construction of alginate materials for use in structural materials for biomedical and engineering purposes. [ABSTRACT FROM AUTHOR]

We propose a novel subsurface pipeline mapping and 3D reconstruction method by fusing ground-penetrating radar (GPR) scans and camera images. To facilitate the simultaneous detection of multiple pipelines, we model the GPR sensing process and prove hyperbola response for general scanning with nonperpendicular angles. Furthermore, we fuse visual simultaneous localization and mapping outputs, encoder readings with GPR scans to classify hyperbolas into different pipeline groups. We extensively apply the J-linkage method and maximum likelihood estimation with error analysis to improve algorithm robustness and accuracy. As a result, we optimally estimate the radii and locations of all pipelines. We have implemented our method and tested it in physical experiments with representative pipeline configurations. Two different kinds of 3-m-long pipes are used, with radii being 4.62 and 3.02 cm, respectively. The results show that our method successfully reconstructs all subsurface pipes. Moreover, the average estimation errors for two orientation angles of pipelines are 1.73° and 0.73°, respectively. The average localization error is 4.47 cm. Note to Practitioners—Automatic and accurate underground pipeline mapping technology is very important in civil construction projects. Lack of 3D utility pipeline maps may lead to accidental damage in civil construction and maintenance. Although ground-penetrating radar (GPR-based pipeline mapping methods have been studied for several years, these methods require the perpendicular scanning with respect to the pipe, which is impossible to guarantee in practice since the orientations of pipelines are unknown. Furthermore, these traditional methods can only estimate one pipeline at a time in a survey area and require prior knowledge of pipe diameter. We propose a robotic subsurface pipeline mapping method with a GPR and a camera to handle difficult factors such as multiple pipes, unknown pipeline orientation, and unknown pipeline diameters. Hence, we can perform GPR scanning along any generic linear trajectories. Our method has been tested in physical experiments with representative pipeline configurations. The results are sufficiently accurate, and it proves that our method can be an effective technology to reconstruct the underground pipelines. [ABSTRACT FROM AUTHOR]

The IR‐drop in the full AMOLED display panel caused by the pixel current is simulated within the mainstream SPICE toolkit to evaluate the display uniformity. Each electrical part of the display panel is simplified and equalized to allow the SPICE doing the very large scale calculation. The implementation of the full panel simulation and the results give better understanding of AMOLED panel design. [ABSTRACT FROM AUTHOR]

Economic growth in the Beijing--Tianjin--Hebei region has been achieved by consuming large amounts of fossil fuels. This produces a large number of pollutants, which damage the physical and mental health of residents, and prevent sustainable economic development. The most urgent task at present is improving the quality of the environment. This paper takes carbon emission as a pollution index, and adopts an extended stochastic impacts by regression on population, affluence, and technology (STIRPAT) model in order to study the impact of the optimization of industry structure (in particular the reduction of the proportion of energy-intensive secondary industry), the optimization of the energy structure, and technological improvements on the atmospheric environmental quality. We obtain some important and enlightening discoveries. First of all, the rapid economic growth that has been based on magnanimous fossil fuel consumption is still the main reason for the deterioration of the atmospheric environment. This means that the main driving force of economic growth still comes from high pollution industries, despite a strategy for the transformation of the pattern of economic growth having been proposed for many years. Second, the optimization of the industrial structure has not played a significant role in promoting the reduction of carbon emissions. Through further research, we believe that this may be due to the low-quality development of the third industry. In other words, the traditional service industry related to high energy consumption accounts for a large proportion in regional total output, while the high-end service industry related to small pollution accounts for a relatively small proportion. Third, reducing the consumption of coal and improving the technological level can effectively curb the deterioration of the environmental quality. In addition, we find that transboundary pollution is an important factor affecting the environment in this region, and the earnings of any unilateral treatment action is small. As a result, joint pollution control under the supervision of the central government can produce greater benefits. Therefore, we believe that the transition of the economic growth pattern, and the optimization of the energy and industry structures (especially developing the high-end service industry) are effective ways to improve the environmental quality. [ABSTRACT FROM AUTHOR]

A Nile red (NR) dye cathode with an asymmetric redox structure of para CN and CO bonds was developed for use in an efficient lithium organic battery with a good capacity of 125 mA h g -1 and two visible discharge/charge voltage plateaus (≈2.0 V and ≈1.7 V). The NR cathode demonstrated the advantages of employing cost-effective dyes to achieve multigradient voltage platform regulation.

Based on the liquid lens focus mechanism, a novel, to the best of our knowledge, optical tactile sensor is designed by taking advantage of the structure simplicity, fast response, and environmental immunity. The design of the tactile sensing mechanism used the liquid-membrane lens structure. To integrate the tactile sensing system, we designed a data acquisition circuit unit. A performance test platform was built, and performance testing and two application demonstrations were conducted. The experiment's result showed that the linear fitting degree was greater than 0.988, the load response time was 0.078 s, the target mass was accurately measured, the maximum error was less than 0.02 N, and the fine adjustment of the LED light intensity was achieved.