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Venture capital (VC) significantly contributes to the development of regional economies and fosters innovation. Analyzing the factors that influence VC investments holds key importance. This study employs two methods to ascertain the relative significance of different factors at the city level: the Lindeman, Merenda, and Gold (LMG) approach in multiple linear regression (MLR) and variable importance in random forest (RF) machine learning. The findings reveal that several factors, including economy, finance, innovation, location, and policy, significantly influence VC investments. Both the MLR and RF models highlight the preeminence of economic and financial variables, followed closely by the city's potential for innovation. Moreover, spatial heterogeneity exists in the importance of these variables. In the economically developed and densely populated eastern regions of China, the financial environment of cities emerges as the most crucial, whereas in the central and western regions, the economy and innovation, respectively, take precedence. This research contributes to a deeper understanding of the distribution of VC investments and offers valuable insights for the development of regional policies. [ABSTRACT FROM AUTHOR]

Since monomers in backbone of poly(butylene succinate-co-adipate) (PBSA) are not entirely derived from bio-based sources, limiting its application in the face of increasingly stringent environmental policies. In this study, a novel full bio-based biodegradable random copolyester poly(butylene succinate-co-sebacicate-co-salicylicate) was successfully synthesized. Detailed investigations were conducted on the structural, mechanical, and degradation characteristics resulting from the introduction of salicylicate and sebacicate units. Introduction of salicylicate units effectively enhanced the mechanical performance. In comparison to PBSA, the tensile modulus of copolymer increased by 20.2% with 10% salicylic acid. Introduction of sebacicate units significantly altered the crystalline structure of copolymer and promote the degradation efficiency. Considering both mechanical strength and degradation efficiency, the copolyester with 2% salicylic acid and 20% sebacic acid was found to meet practical application requirements. Relative to PBSA, this copolymer demonstrated a 13.7% increase in tensile modulus and a remarkable 143.1% improvement in degradation efficiency. Importantly, this study focused on the effect of the bio-based rigid monomer salicylic acid and the soft monomer sebacic acid on the degradability of biodegradable polymers. The insights gained provide valuable guidance for tailoring the synthesis of degradable plastics to meet diverse degradation cycle requirements. [ABSTRACT FROM AUTHOR]

Perioperative neurocognitive disorders (PNDs) are now considered the most common neurological complication in older adult patients undergoing surgical procedures. A significant increase exists in the incidence of post-operative disability and mortality in patients with PNDs. However, no specific treatment is still available for PNDs. Recent studies have shown that exercise may improve cognitive dysfunction-related disorders, including PNDs. Neuroinflammation is a key mechanism underlying exercise-induced neuroprotection in PNDs; others include the regulation of gut microbiota and mitochondrial and synaptic function. Maintaining optimal skeletal muscle mass through preoperative exercise is important to prevent the occurrence of PNDs. This review summarizes current clinical and preclinical evidence and proposes potential molecular mechanisms by which perioperative exercise improves PNDs, providing a new direction for exploring exercise-mediated neuroprotective effects on PNDs. In addition, it intends to provide new strategies for the prevention and treatment of PNDs. [ABSTRACT FROM AUTHOR]

In recent years, the frequent occurrence of forest fires has caused serious impact on the environment and economy. Fire detection has become a hot research direction. Despite the remarkable achievements, the unmanned aerial vehicle (UAV) still has some problems such as insufficient precision and excessive parameters. In order to improve the application ability of UAV in forest fire prevention and control, a lightweight target detection model based on YOLOv5 is proposed. The model is based on the overall structure of YOLOv5, MobileNetV3 is used as the backbone network, and semi-supervised knowledge distillation (SSLD) is used for training to improve the convergence speed and accuracy of the model. The final model size was reduced by 94.1% from 107.6 MB to 6.3 MB. mAP0.5 increased by 0.8% and mAP0.95 increased by 2.6%. The improved lightweight YOLOv5 model has fewer parameters and less computation, which confirms that MobileNetV3 has an excellent effect on the compression of model memory, and the semi-supervised knowledge distillation method is beneficial to improve the accuracy of the model. In the future, the accuracy of the model and the detection rate of the covered flame should be further improved. [ABSTRACT FROM AUTHOR]

The generation of alkyl radical from C(sp3)−H substrates via hydrogen atom abstraction represents a desirable yet underexplored strategy in alkylation reaction since involving common concerns remain adequately unaddressed, such as the harsh reaction conditions, limited substrate scope, and the employment of noble metal- or photo-catalysts and stoichiometric oxidants. Here, we utilize the synergistic strategy of photoredox and hydrogen atom transfer (HAT) catalysis to accomplish a general and practical functionalization of unactived C(sp3)−H centers with broad reaction scope, high functional group compatibility, and operational simplicity. A combination of validation experiments and density functional theory reveals that the N-centered radicals, generated from free N − H bond in a stepwise electron/proton transfer event, are the key intermediates that enable an intramolecular 1,5-HAT or intermolecular HAT process for nucleophilic carbon-centered radicals formation to achieve heteroarylation, alkylation, amination, cyanation, azidation, trifluoromethylthiolation, halogenation and deuteration. The practical value of this protocol is further demonstrated by the gram-scale synthesis and the late-stage functionalization of natural products and drug derivatives. Hydrogen atom abstraction from C(sp3)−H substrates for the generation of alkyl radical represents an underexplored strategy in alkylation reactions. Here the authors describe the synergistic utilization of photoredox and hydrogen atom transfer catalysis to accomplish a general and practical functionalization of unactived C(sp3)−H centers. [ABSTRACT FROM AUTHOR]

Background: Choledochoscopy is a highly effective approach for managing intrahepatic bile duct stones (IHDs). However, postoperative infection is a common complication that significantly impacts treatment outcomes. Despite its clinical relevance, the risk factors associated with this procedure remain largely unexplored. Methods: This study focused on a consecutive cohort of patients who underwent choledochoscopy for IHDs at our institution between January 2016 and December 2022. The primary objective was to analyze the relationship between various clinical factors and postoperative infection, and to compare the postoperative infection of different choledochoscopic procedures. Results: The study cohort consisted of 126 patients, with 60 individuals (47.6%) experiencing postoperative infection. Notably, preoperative biliary obstruction (odds ratio [OR] 1.861; 95% confidence interval [CI] 1.314–8.699; p = 0.010) and operation time (OR 4.414; 95% CI 1.635–12.376; p = 0.004) were identified as risk factors for postoperative infection. Additionally, biliary tract infections (60.00%) were primarily responsible for postoperative infection, with Escherichia coli (47.22%) being the predominant bacterial strain identified in bile cultures. Furthermore, biliary tract obstruction (OR 4.563; 95% CI 1.554–13.401; p = 0.006) and body mass index (BMI) (OR 1.186; 95% CI 1.015–1.386; p = 0.031) were determined to be independent risk factors for postoperative biliary tract infection. Conclusions: The occurrence of postoperative infection in patients undergoing choledochoscopy was primarily associated with the duration of the operation and the presence of preoperative biliary obstruction. [ABSTRACT FROM AUTHOR]

The hot extrusion process can effectively refine the coarse grains of metastable β titanium alloy billet, thereby enhancing the material's internal microstructure and mechanical properties. This study explored the hot deformation behavior of as-cast Ti-6554 samples at temperatures ranging from 900 °C to 1150 °C and strain rates between 0.001 s-1 and 1 s-1 by a Gleeble-3500 tester. The Arrhenius constitutive model was established to simulated the hot extrusion process. Parameters such as the degree of deformation (x), metal plastic flow (μ), and deformation temperature (θ) were introduced to quantify the uniformity of distribution under various processes. Based on the simulation results, the optimal extrusion conditions were determined to be an extrusion ratio of 10, an extrusion angle of 60°, an extrusion velocity of 40 mm/s, a preheating temperature of 1100 °C, and an extrusion load of 2500 tf. Examination of the microstructure of the hot-extruded bar revealed that grain sizes consistently decreased from the centers towards the edges. The grains were refined from 2000~5000 μm to 100~200 μm after extrusion, demonstrating that the deformation degree, plastic flow and deformation temperature were well coordinated under these conditions. [ABSTRACT FROM AUTHOR]

Hot compression experiments are conducted on the Gleeble-3500 device to study the flow behaviors and hot workability of typical ultrahigh strength steel (UHSS) during the isothermal forging process. An improved Johnson–Cook (J–C) constitutive model is proposed to describe the flow behaviors, which considers the interaction effect of different deformation parameters. The proposed constitutive model shows a high prediction accuracy with an average absolute error of 5.07%. Furthermore, according to the critical strain and the logarithm of the Zener–Hollomon parameter, the mathematical models for the distribution and size of austenite grains are established, which can be used to quantitatively evaluate the effects of dynamic recrystallization (DRX) on the microstructure evolution. Considering the importance of microstructures, a new evaluation approach for hot workability is proposed, which integrates the grain size and DRX degree in the traditional processing maps. In comparison to the traditional processing maps, the newly proposed optimization method can assure the full occurrence of DRX, uniformity and fineness of grains, and absence of flow instability within the optimized processing parameter range. The processing parameters can be optimized to 0.01–0.075 s−1 and 1263–1363 K by the newly proposed evaluation approach. The average grain size of the UHSS is 20.85–40.66 μm within the optimized processing parameters, which well meets the grain size requirements for forgings. [ABSTRACT FROM AUTHOR]

With the rapid development of synthetic aperture radar (SAR) technology, SAR image ship detection plays a crucial role in fields such as marine environment monitoring and maritime traffic control. Due to the large-scale difference between ship targets and the small spatial feature information of targets in complex environments, the existing network models have low detection accuracy and cannot achieve satisfactory performance. Therefore, in this paper, a SAR ship detection network (FGNet) based on global context and multi-scale feature enhancement is proposed. The method adopts the global context block (GC block) to effectively model the global context information of the feature map and enhance the network's focus on important features. In addition, we propose the feature enhancement module (FEM), which enhances the network's feature representation capability for ships of different scales by designing a multi-branch structure with varying receptive field sizes. Experimental results on the SAR-Ship-Dataset and SSDD datasets show that the average accuracy of our method is 95% and 96.58%, respectively. Compared with other ship detection methods, the method has high detection accuracy and excellent generalization performance. [ABSTRACT FROM AUTHOR]

Rab27A is a small GTPase-mediating exosome secretion, which participates in tumorigenesis of multiple cancer types. Understanding the biological role of Rab27A in non-small cell lung cancer (NSCLC) is of great importance for oncological research and clinical treatment. In this study, we investigate the function and internal mechanism of Rab27A in NSCLC. Results show that Rab27A is overexpressed in NSCLC, and regulates the tumor proliferation, migration, invasion, and cell motility in vitro and in vivo, and is negatively regulated by miR-124. Further research reveals that upregulated Rab27A can induce the production of IFNα in the medium by mediating exosome secretion. Then IFNα activates TYK2/STAT/HSPA5 signaling to promote NSCLC cell proliferation and metastasis. This process can be suppressed by TYK2 inhibitor Cerdulatinib. These results suggest that Rab27A is involved in the pathogenesis of NSCLC by regulating exosome secretion and downstream signaling, and inhibitors targeting this axis may become a promising strategy in future clinical practice. [ABSTRACT FROM AUTHOR]

The construction of super large section (SLS) shallow buried tunnels involves challenges related to their large span, high flat rate, and complex construction process. Selecting an appropriate excavation method is crucial for ensuring stability, controlling costs, and managing the construction timeline. This study focuses on the selection of excavation methods and the mechanical responses of SLS tunnels in different types of surrounding rock. The research is based on the Yangjiashan tunnel project in Zhejiang Province, China, which is a four-line highway tunnel with a span of 21.3 m. Three sequential excavation methods were proposed and simulated using the three-dimensional finite difference method: the "upper first and lower later" side drift (SD) method, the central diaphragm method, and the top heading and bench (HB) method. The mechanical response characteristics of tunnel construction under these methods were investigated, including rock deformation, rock pressure, and the internal forces acting on the primary support. By comparing the performance of the three construction methods in rock masses of Grades III to V, the study aimed to determine the optimal construction method for SLS tunnels considering factors such as safety, cost, and schedule. Field tests were conducted to evaluate the effectiveness of the optimized construction scheme. The results of the field monitoring indicated that the "upper first and lower later" SD method in Grade V rock mass and the HB method in Grade III to IV rock mass are feasible and cost-effective under certain conditions. The research findings provide valuable insights for the design and construction of SLS tunnels in complex conditions, serving as a reference for engineers and project managers. [ABSTRACT FROM AUTHOR]

Efficient removal of silica is the key to alumina extraction from coal fly ash (CFA) by the Bayer process, due to the easy formation of sodium aluminosilicate hydrates during alkaline digestion. Considering the main mineral of well-crystallized mullite in CFA, mechanical activation was used in this work to improve the silica removal during reduction roasting–alkaline leaching. The phase transformations occurring in CFA during mechanical activation, reduction roasting, and alkaline leaching were systemically investigated through MAS-NMR, XRD, and SEM-EDS analyses. The results showed that the mean particle size (d(50)) decreased from 17.98 μm in CFA to 2.03 μm in activated CFA for 10 min with prolonging mechanical activation time, with the corresponding Al(IV) content decreasing from 73.82% to 67.85%. After pre-treatment with mechanical activation, the conversion of CFA into hercynite and silica solid solutions (i.e., quartz solid solution and cristobalite solid solution) was improved during reduction roasting with hematite, and the silica leaching ratio increased from ~ 70% to ~ 90% during the alkaline leaching. The obtained leaching residue with an alumina to silica mass ratio of > 10 was a decent raw material for the Bayer process to extract alumina. This study lays the foundation for comprehensive utilization of CFA. [ABSTRACT FROM AUTHOR]

Action Quality Assessment (AQA) is a critical branch of video understanding, offering impartial evaluations for competitive sports. Existing paradigms tend to assess action quality using equal-length clips that lack sufficient semantics, leading to suboptimal predictions. To address this issue, we propose to conduct AQA with Semantic-Sequence Performance Regression (SSPR). SSPR first divides an action into a series of unequal-length segments according to the semantic continuity of the video, such as jumping, dropping, and entering the water in diving. Specifically, the latest Temporal Convolutional Network (TCN) is adopted for semantic-sequence segmentation. To better achieve SSPR, we design a feature fusion module that integrates the semantics of each segment using cascaded 1D convolutions. Furthermore, the imbalanced distribution phenomenon is usually ignored in AQA and we attempt to propose a new loss called positive-weighting MSE (PW-MSE) to deal with it. PW-MSE encourages the network to focus more on densely distributed samples during training, which further improves the network's ranking performance. Experimental results on the benchmark datasets (i.e., UNLV-Dive and AQA-7) demonstrate that our proposed method outperforms the current state-of-the-arts. [ABSTRACT FROM AUTHOR]

Heavy components of low-alloy high-strength (LAHS) steels are generally formed by multi-pass forging. It is necessary to explore the flow characteristics and hot workability of LAHS steels during the multi-pass forging process, which is beneficial to the formulation of actual processing parameters. In the study, the multi-pass hot compression experiments of a typical LAHS steel are carried out at a wide range of deformation temperatures and strain rates. It is found that the work hardening rate of the experimental material depends on deformation parameters and deformation passes, which is ascribed to the impacts of static and dynamic softening behaviors. A new model is established to describe the flow characteristics at various deformation passes. Compared to the classical Arrhenius model and modified Zerilli and Armstrong model, the newly proposed model shows higher prediction accuracy with a confidence level of 0.98565. Furthermore, the connection between power dissipation efficiency (PDE) and deformation parameters is revealed by analyzing the microstructures. The PDE cannot be utilized to reflect the efficiency of energy dissipation for microstructure evolution during the entire deformation process, but only to assess the efficiency of energy dissipation for microstructure evolution in a specific deformation parameter state. As a result, an integrated processing map is proposed to better study the hot workability of the LAHS steel, which considers the effects of instability factor (IF), PDE, and distribution and size of grains. The optimized processing parameters for the multi-pass deformation process are the deformation parameters of 1223–1318 K and 0.01–0.08 s−1. Complete dynamic recrystallization occurs within the optimized processing parameters with an average grain size of 18.36–42.3 µm. This study will guide the optimization of the forging process of heavy components. [ABSTRACT FROM AUTHOR]

Domain generalization is a key problem to solve the difference between the source domain and the target domain. This paper proposes a person re-identification algorithm based on meta-graph aware (Meta-GA) under the framework of meta-learning, which includes two stages: meta-global aware (M-GA) and meta-graph relationship sampling (M-GRS). In order to reduce inter-domain differences, a meta-global aware mechanism is proposed to construct an interaction model (paired relationship) in the meta training domain by stacking affinity models and dividing saliency features between the pedestrians. Then a learning interaction model is used to construct a global knowledge map to classify and weighted the structural information. In order to accurately learn the discriminative features, a meta-graph relationship sampling model is proposed. The similarity of the pedestrian cross-domain features between the domains is used to construct a feature relationship map between the adjacent classes. To enhance domain invariant features and improve the model generalization, positive samples are sampled cyclically and negative samples are sampled randomly. On this basis, the gradient norm is trimmed to prevent the model overfitting. The experimental results show that the robustness and accuracy of the proposed algorithm have been significantly improved. In the Market-1501 to DukeMTMC-ReID experiment, Rank-1 and mAP increased by 5.25% and 3.73%, respectively. In the DukeMTMC-ReID to Market-1501 experiment, Rank-1 and mAP increased by 1.73% and 0.93%, respectively, which are significantly superior to those of the recent representative algorithms. [ABSTRACT FROM AUTHOR]

Forest fire may have very serious impacts on the natural environments and human beings. It is important to detect the source of a fire before it spreads. The existing flame detection algorithm has the problem of weak generalization and not fully considering the influence of flame target size on detection. To enhance the ability of flame detection of different sizes, ground flame data and UAV forest flame data were combined in this study. Cosine annealing algorithm, label smoothing and multi-scale training were introduced in order to improve the detection accuracy of the model. The experimental results show that our improved YOLOv5 has strong generalization and good detection effect for different sizes of flames. The mAP50 value of the improved YOLOv5 reaches 93.8%, which is 7.4% higher than YOLOv5 (mAP50) and 14.8% higher than YOLOv5 (mAP95). The proposed model has the advantages of strong generalization and low false detection rate, and has high detection accuracy for flame targets at different scales. [ABSTRACT FROM AUTHOR]

Purpose: It was of great significance to identify someone with a high risk of hepatocellular carcinoma (HCC) occurrence and make a diagnosis as early as possible. Therefore, we aimed to develop and validate a new, objective, and accurate prediction model, and convert it into a nomogram to make a personalized prediction of cancer occurrence in cirrhotic patients with different etiologies. Methods: The present study included 938 patients with cirrhosis from January 1, 2011, to December 31, 2012. Patients were prospectively followed-up until January 1, 2018. We used a competing risk model and the Fine–Gray test to develop and validate the prediction model and to plot a nomogram based on the model established. Results: At the end of follow-up, 202 (21.5%) patients developed HCC, with a 5-year incidence of 19.0% (corrected for competing risk model). Based on the competing risk regression method, we built a prediction model including age, gender, etiology, lymphocyte, and A/G ratio. Three groups with different risks were generated on account of tertiles of the 5-year risk predicted by the model. The cumulative 1-, 3-, and 5-year incidences of HCC were 2.0%, 20.8%, and 42.3% in high-risk group, 0.9%, 10.1%, and 17.7% in medium-risk group, and 0%, 2.0%, 8.5% in low-risk group (P < 0.001). The model showed excellent discrimination and calibration in predicting the risk of HCC occurrence in patients with all-cause cirrhosis. Conclusion: The model could make an individual prediction of cancer occurrence and stratify patients based on predicted risk, regardless of the causes of cirrhosis. [ABSTRACT FROM AUTHOR]

The genomic instability (GI) /homologous recombination deficiency (HRD) score, calculated as the sum of the events of loss of heterozygosity (LOH), large-scale state transition (LST) and telomere allele imbalance (TAI), is used to guide the choice of treatment in several cancers, but its relationship with genomic features, clinicopathological characteristics and prognosis in lung cancer is poorly understood, which could lead to population bias in prospective studies. We retrospectively analyzed 1011 lung cancer patients whose tumor samples were successfully profiled by high-throughput sequencing panel including GI/HRD score. Alterations of many cancer suppressor genes were associated with higher GI/HRD scores, biallelic inactivation of TP53 was correlated with a high GI/HRD score. A combination of two gene alterations exhibited a higher GI/HRD scores than single gene alterations. The GI/HRD score was associated with advanced stages in lung adenocarcinoma but not in lung squamous cell carcinoma. Furthermore, patients with higher GI/HRD scores had significantly shorter overall survival and progression-free survival than patients with lower GI/HRD scores. Finally, patients with a combination of a higher GI/HRD scores and TP53 alteration exhibited an extremely poor prognosis compared with patients with a lower GI/HRD scores and wild-type TP53 (overall survival, training cohort, hazard ratio (HR) = 8.56, P < 0.001; validation cohort, HR = 6.47, P < 0.001; progression-free survival, HR = 4.76, P < 0.001). Our study revealed the prognostic value of the GI/HRD score in lung adenocarcinoma, but not for all lung cancer. Moreover, the combination of the GI/HRD score and TP53 status could be a promising strategy to predict the prognosis of patients with lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

The combination of wire arc additive manufacturing (WAAM) technology with traditional manufacturing process provides a promising method for fabricating the large and complex parts with the advantages of high performance, time-saving, low cost and high material utilization. In order to acquire the optimal hybrid manufacturing process, the comparative study of flow behaviors and microstructure evolution of wrought and WAAMed ultrahigh-strength (UHS) steels is carried out under the temperatures of 920–1160 o C and strain rates of 0.01–10 s - 1 . The results show that the coarse prior austenite columnar grains and carbides in the initial microstructure of the WAAMed UHS steel contribute to the higher flow stress and slower dynamic recrystallization (DRX) kinetics during hot deformation as compared to the wrought UHS steel. The hot activation energy under the peak stress of the wrought and WAAMed UHS steels is estimated to be 332.3 kJ/mol and 374.1 kJ/mol, respectively. On the basis of the hot processing maps, the common optimal processing window for WAAMed and wrought UHS steels is determined as the temperatures of 1060–1160 o C and strain rates of 0.08–0.66 s - 1 . Under these deformation parameters, the microstructures of WAAMed and wrought UHS steels consist of fine DRXed grains, and the DRX behaviors are both dominated by the discontinuous DRX and continuous DRX mechanisms. [ABSTRACT FROM AUTHOR]

A highly sensitive method was developed for the determination of 17 nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) in PM2.5 using an ultrasound-assisted extraction (UAE)-online solid phase extraction (online SPE)-liquid chromatography-tandem mass spectrometry (LC/MS). The method underwent comprehensive optimization, encompassing UAE solvents and times, extract filtering, online SPE condition and LC/MS condition. Isomeric separation and detection of mononitro-PAHs, dinitro-PAHs, and OPAHs were achieved based on the proposed MS/MS fragmentation pathway in negative mode atmospheric pressure chemical ionization. Taking the advantage of online SPE, the method achieved lower limits of detection (NPAHs: 0.001 ~ 0.042 μg L−1, OPAHs: 0.01 ~ 0.038 μg L−1). Recovery ranged from 64% ~ 108% at three spiking levels (0.25, 1.0 and 10.0 μg L−1) with the relative standard deviations (RSDs) of 3% ~ 23%. This study represents first application of LC/MS methodology for the quantification of three carcinogenic dinitro-PAHs (1,3-dinitropyrene, 1,6-dinitropyrene, 1,8-dinitropyrene) in atmospheric PM2.5. The established method was successfully employed to determine the wide range concentrations of various NPAHs and OPAHs (∑NPAH: 9.4 ~ 303.3 pg m−3, ∑OPAHs: 125.2 ~ 1948.1 pg m−3) in PM2.5 samples collected in Beijing during the summer and winter seasons. [ABSTRACT FROM AUTHOR]

Urban waterlogging can cause considerable economic damage, public inconvenience, and even mortality. Effective prediction of inundation probability on an urban agglomeration scale is an essential step in adaptation planning. This study proposes an urban waterlogging exposure assessment framework using the Weighted Naive Bayesian (WNB) classifier and a Complex Network Model (CNM). WNB classifier delineates the risk distribution projections by assimilating risk factors and empirical data of urban waterlogging events. This projection was subsequently validated using an overarching accuracy coefficient of 0.85 and a Kappa coefficient of 0.75, these numerical metrics serving as critical evaluative thresholds for the verification of the WNB model's efficacy and precision. CNM is used to analyze the composition and correlation of system risk attributes according to its network topology. We applied the proposed framework to the Guangdong-Hong Kong-Macao Greater Bay Area (GBA). We found that 20.0% of the study areas are exposed to waterlogging risk, of which 1.4% of the study areas are at high risk. There is a clear spatial concentration of urban waterlogging risks in the downtown area of populated cities. In addition, according to CNM, the urban waterlogging hazards of most townships are stressed by multiple factors such as fractional vegetation cover, impervious surface percentage, and soil water retention. The townships stressed by a single factor are attributed to the distance from the waterway or road density. The framework could provide in-depth insights into urban waterlogging preparedness and emergency response. [ABSTRACT FROM AUTHOR]

L 0 norm plays a crucial role in sparse optimization, but discontinuities and non-convexity make the minimization of the l 0 norm be an NP-hard problem. To alleviate this problem, we design a smoothing function based on the sigmoid function to approximate the l 0 norm. To illustrate the physical realizability of the smoothing function and the advanced quality of the approximation, the proposed smoothing function is compared experimentally with several existing smoothing functions. Additionally, we analyze the parameters in the functions to determine the quality of the approximation. We investigate the circuit implementation of the proposed function and five existing smoothing functions; the simulation results show the effectiveness of the designed circuit on the Multisim platform. Experiments on the reconstruction of simulated sparse signals and real image data show that the proposed smoothing function is able to reconstruct sparse signals and images with lower mean square error (MSE) and higher peak signal-to-noise ratio (PSNR), respectively. [ABSTRACT FROM AUTHOR]

Aliphatic and aliphatic–aromatic polyesters are used widely in the food packaging field, which is very concerned about the volatile organic compound (VOC). Typical VOCs in poly (butylene succinate) (PBS) and poly (butylene adipate-co-terephthalate) (PBAT) are oligomers, especially cyclic esters, which were studied using GPC, MALDI-FTICR-MS and UPLC-FTICR-MS technique. Cyclic esters with repeating unit 2–8 were found in PBS; cyclic esters with repeating unit 1–10 (or more) were found in PBAT derived from three monomers with almost all possible random combinations. Cyclic esters with repeating unit 2–4 were the most abundant structures, but only cyclic esters with repeating unit 1–3 were found in the crystalline extracted from the recovered butanediol from the product line. Cyclic esters with repeating unit 1–3 can also be extracted from methanol at 70 °C for 1 h, and the content of linear oligomers increased with increasing temperature to 200 °C. But PBAT resin cannot be decomposed to monomers at 200 °C for 1 h in methanol without other additives. [ABSTRACT FROM AUTHOR]

Intracranial hemorrhage (ICH) is a major cause of early death (ED) and leads to poor prognosis in acute promyelocytic leukemia (APL). We retrospectively described 27 unselected APL patients who experienced early ICH. The ED rate was 37%. The 3-year overall survival (OS) rate was 45.4%, while the 3-year OS rate of patients who survived through induction therapy was 87.5%. No patient experienced central nervous system leukemia (CNSL). Concurrent differentiation syndrome, white blood cell count, prothrombin time and D-dimer were related to death. Although the ED rate among APL patients with early ICH was high, patients with early ICH had a favorable outcome after surviving through induction therapy. CNSL was rare despite a history of ICH during induction therapy. Compared with APL patients without ICH, it seems unnecessary to administer additional measures to prevent CNSL for this subpopulation in the era of all-trans retinoic acid and arsenic trioxide, but this needs further validation in prospective trials. [ABSTRACT FROM AUTHOR]

Lung adenocarcinoma (LUAD) is the main cause of cancer-related death worldwide. Understanding the mechanisms of LUAD progression may provide insights into targeted therapy approaches for this malignancy. Ubiquitin-conjugating enzyme 2 N (UBE2N) has been demonstrated to play key roles in the progression of various cancers. However, the functions and mechanisms underlying UBE2N expression in LUAD are still unclear. In this study, we found that UBE2N is highly expressed in LUAD and patients with high UBE2N expression in their tumors have poor clinical outcomes. Moreover, we showed that UBE2N interference significantly inhibited LUAD progression in vitro and in vivo. At the molecular level, we demonstrated that the UBE2N is a bona fide target of transcription factor SP1. SP1 directly bound to the promoter of UBE2N and upregulated its expression in LUAD cells, which in turn contributed to the progression of LUAD. Furthermore, we found that there is a strong positive correlation between the expression of SP1 and UBE2N in LUAD samples. Importantly, LUAD patients with concomitantly high expression of SP1 and UBE2N were significantly associated with poor clinical outcomes. In conclusion, our study demonstrated that the SP1-UBE2N signaling axis might play a key role in the malignant progression of LUAD, which provides new targets and strategies for the treatment of LUAD. [ABSTRACT FROM AUTHOR]

Flexible photovoltaics have been and will be increasingly in demand in modern and future society in various applications. Searching for ideal flexible photovoltaic technologies that can perfectly meet these expanding demands has long been an active branch of photovoltaic research. Flexible kesterite Cu2ZnSn(S,Se)4 (CZTSSe) has emerged in recent years owning to its great potential to be an abundant, low-cost, stable, and high-efficiency 'green' photovoltaic material that can be widely deployed with the lowest detrimental environmental impact. Here, we review the recent progress with flexible kesterite solar cells in thin-film and monograin technologies, discuss the key challenges and strategies associated with the flexible substrates, and finally provide the future perspectives on further pushing the efficiency toward commercial-competitive levels. [ABSTRACT FROM AUTHOR]

In order to effectively achieve the quality classification of sunflower seeds based on appearance identification in production scenarios, a multi-objective sunflower seed classification method based on a self-attention mechanism was proposed in this paper, which achieves the classification of sunflower seed object images with an accuracy of 94.71% by using a Multi-Head Self-attention mechanism to focus on the classification objects on the basis of effectively extracting context-dependent information from sunflower seed images. However, visualization experiments found that the model's attention could not effectively focus on the class activated regions of the image, resulting in a model that was heavily influenced by background noise and suffered from such defects as high computational cost and large model size. To address the above problems, a self-attention Focusing algorithm was proposed in this paper by evaluating and reconstructing the connections in the attention weight matrix, pruning the less influential connections, and realizing the update of the attention score, which gradually focuses attention on the class activated regions in continuous iterations, effectively shielding the background noise. Experiments have shown that applying the Focusing algorithm improves the accuracy rate to 96.6% based on a 34.3% reduction in the number of model parameters. Model accuracy was successfully improved while achieving model lightweighting, and the model was made more resistant to background noise due to the focused attention region. The self-attention Focusing algorithm's effectiveness in improving accuracy, focusing attention, and compressing model size is demonstrated. In practical production scenarios, it can be used as a popular application of key techniques for sunflower seed classification. [ABSTRACT FROM AUTHOR]

Chronic active EBV infection (CAEBV) is a lymphoproliferative disorder of T- or NK-cell type in Asian countries. CAEBV involving the gastrointestinal tract (GI CAEBV) is a rare condition with poor prognosis that may rapidly progress with hemophagocytic lymphohistiocytosis (HLH) and life-threatening complications such as GI bleeding and/or perforation. The approach to CAEBV with GI tract involvement (GI CAEBV) is still an unmet clinical need. In this case series study, we summarized the clinical features, treatment, and prognosis of seven cases of GI CAEBV with HLH, particularly focusing on its prognosis and the possible salvage therapy combining surgery, novel therapeutic agents, and/or autologous(auto-) hematopoietic stem cell transplantation (HSCT) based on successful cases from our center. GI CAEBV is often misdiagnosed as inflammatory bowel diseases and certain infections. The key to its early recognition is the integrative consideration of its systemic manifestation, serum virology, endoscopic, and imaging findings along with pathology. Surgical intervention should not be hesitated when life-threatening GI complications occur. Resection of the involved bowel segment is an effective way of controlling bleeding and reducing tumor burden. In addition to upfront allogeneic HSCT, new therapeutic modalities including PD-1 antibody and auto-HSCT may be effective in certain patients. [ABSTRACT FROM AUTHOR]

Kesterite Cu2ZnSn(S, Se)4 (CZTSSe) thin film solar cells have been regarded as one of the most promising thin film photovoltaic technologies, offering a low-cost and environmentally friendly solar energy option. Although remarkable advances have been achieved in kesterite solar cells, the performance gap relative to mature thin film photovoltaic technologies such as CIGSe and CdTe remains large. Significant open-circuit voltage (VOC) deficit has been recognized as the main limiting factor to performance improvement, with undesirable intrinsic defects being a key culprit contributing to the low VOC. To realize the promise inherent in kesterite CZTS to become an earth-abundant alternative to existing thin film photovoltaic technologies with comparable performance, significant research effort has been invested to tackle the challenging defect issues. In this review, recent progress and achievements relevant to engineering improvements to the defect properties of the semiconductor have been examined and summarized. Promising strategies include: (i) manipulating the synthesis process to obtain a desirable reaction pathway and chemical environment; (ii) introducing cation substitution to increase the ionic size difference and supress the related band tailing deep-level defects; (iii) applying post deposition treatment (PDT) with alkaline elements to passivate the detrimental defects. These advances obtained from work on kesterite solar cells may lead to future high performance from this material and may be further extended to other earth-abundant chalcogenide photovoltaic technologies. [ABSTRACT FROM AUTHOR]

A series of novel indole derivatives were designed, synthesized and evaluated for the binding affinity of Bcl-2 family proteins and antiproliferative activity against three selected cancer cell lines (PC-3, Jurkat, and MDA-MB-231). The preliminary structure-activity relationship (SAR) for this indole scaffold was summarized. Among all the compounds, compound 9k showed the best inhibitory activity against Bcl-2 and Mcl-1 proteins with IC50 values of 7.63 µM and 1.53 µM, respectively, which is comparable to the positive control AT-101. The docking study of it with Bcl-2 and Mcl-1 proteins indicated that it could bind to the active pocket of them through Van der Waals forces, hydrogen bond, etc. However, the three compounds with good binding affinity of Bcl-2 protein exhibited weaker antitumor activity compared to AT-101, which need further modification. [ABSTRACT FROM AUTHOR]

Recent progress has been made in the application of novel zirconium-loaded amine-grafted walnut shells as multifunctional adsorbents for the remediation of Alizarin red (AR) and bacteria in aqueous solutions. The morphology and functional groups of ACWNS@Zr were studied using Brunauer–Emmett–Teller (BET) techniques, X-ray diffraction (XRD), pH point of zero charges (pHpzc), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. Adsorption and regeneration tests were carried out in batch and column mode. The ACWNS@Zr had a Langmuir maximum capacity of 415.5 ± 6.1 mg g−1 at 303 K. The spread plate technique was used to evaluate the adsorbent's antimicrobial properties against Staphylococcus aureus and Escherichia coli. ACWNS@Zr exhibited inhibitory potential towards S. aureus and E. coli in the suspensions by 53.3% and 15.0%, respectively. Electrostatic interaction and complexation interaction could be the key mechanisms governing AR dye removal. Equilibrium isotherms fit Langmuir models better for both batch and column studies, while adsorption kinetics to pseudo-second-order and Thomas models for batch and column studies, respectively. Thermodynamic studies indicated that the adsorption process was endothermic and spontaneous. Furthermore, columns' mass transfer capacity (B) increased as the concentration increased due to the enhanced driving force for AR adsorption onto ACWNS@Zr. Regeneration with NaOH solution of AR-loaded ACWNS@Zr was remarkable. [ABSTRACT FROM AUTHOR]

Change detection is a fundamental problem in remote sensing image processing. Due to the great advantages in learning the knowledge representations and the complex relationship from large-scale datasets, deep learning has made great progress in change detection tasks in remote sensing community. However, most of the existing methods based on deep learning for change detection are implemented by learning differences of image pairs directly without paying considerations in influences of unstructured and temporal changes, or called nature changes, such as light and seasonal changes. In this paper, an end-to-end deep learning network for remote sensing image change detection is proposed, aiming to accurately detect the change of regions from a high-resolution image pair by learning prototype similarity, in which the metric learning is used and it is one of the meta-learning methods to learn change prototypes from support image pairs. The similarity between the query image pairs and the change prototypes can be measured by a learnable CNN metric. The experimental results based on the two public change detection datasets of high-resolution satellite images, CDD and BCDD, show that our proposed method performs better than other state-of-the-art change detection methods with an improvement of 3.5% and 0.4%, respectively. [ABSTRACT FROM AUTHOR]

Eccrine sweat gland (SG) restrictedly exists in mouse foot pads indicating that mouse plantar dermis (PD) contains the SG lineage-restricted niches. However, it is still unclear how these niches can affect stem cell fate towards SG. In this study, we tried to find the key cues by which stem cells sense and interact with the SG lineage-specific niches both in vivo and in vitro. Firstly, we used transcriptomics RNA sequencing analysis to screen differentially expressed genes between SG cells and epidermal stem cells (ES), and used proteomic analysis to screen differentially expressed proteins between PD and dorsal dermis (DD). Notch1 was found differentially expressed in both gene and protein levels, and was closely related to SG morphogenesis based on Gene Ontology (GO) enrichment analysis. Secondly, the spatial-temporal changes of Notch1 during embryonic and post-natal development of SG were detected. Thirdly, mouse mesenchymal stem cells (MSCs) were introduced into SG-like cells in vitro in order to further verify the possible roles of Notch1. Results revealed that Notch1 was continuously down-regulated along with the process of SG morphogenesis in vivo, and also along with the process that MSCs differentiated into SG-like cells in vitro. Hence, we suggest that Notch1 possibly acts as with roles of "gatekeeper" during SG development and regulates the interactions between stem cells and the SG lineage-specific niches. This study might help for understanding mechanisms of embryonic SG organogenesis. [ABSTRACT FROM AUTHOR]

Electromagnetic incremental forming (EMIF) is employed for forming large-sized parts of aluminum. The basic characteristic of EMIF is multi-electromagnetic forming (EMF). The forming uniformity of a multi-EMF is the key to the success of an EMIF method. In this study, first, several important parameters affecting the forming uniformity of single EMF are studied using orthogonal experimental research scheme. In order to conduct a comparative study on the forming uniformity of the multi-EMF, two-coil moving strategy is selected. Thereafter, the effect of overlap ratio on the forming uniformity of the multi-EMF is studied using the coil sequence moving strategy. The effect of shaping voltage is also investigated using the coil spaced moving strategy. Based on the findings, the optimum conditions of forming uniformity of the multi-EMF are obtained. An experimental verification of the simulation results is also conducted. The obtained results present a viable method and guidance for EMIF of large-sized aluminum alloy sheet metal parts. [ABSTRACT FROM AUTHOR]

Discharge coil is the core component of the traditional electromagnetic forming technology. However, the machining of discharge coil is difficult, and the manufacturing cost is expensive. The durability of the coil is also challenged due to the effect of temperature rise, and accumulated coil deformation leads to a change in coil parameters during multiple discharges, which seriously restricts the industrial application of electromagnetic forming. This paper proposes a new electromagnetic forming method, named direct pulse current electromagnetic forming (DPCEMF). The traditional electromagnetic forming method loads the current to the coil, and then, an eddy is inducted on the surface of the workpiece conductor near the coil. However, the new method is a reverse approach, that is, the workpiece is directly loaded with a pulse current, and the surface of the high-conductivity metal block near the workpiece induces an opposite eddy and produces a repulsive electromagnetic force, which in turn causes the high-speed deformation of the workpiece. The discharge coil of conventional electromagnetic forming is replaced with a high-conductivity metal block, which greatly improves the strength, service life, and reliability of the forming system. The DPCEMF process is thermoplastic electromagnetic forming in which heating and electromagnetic forming are conducted simultaneously and completed in microseconds. The method has been well verified by experiments to overcome the forming of a difficult-to-form material, taking a solid step toward realizing the industrial application of electromagnetic forming. [ABSTRACT FROM AUTHOR]

A new electromagnetic forming method named direct pulse current electromagnetic forming (DPCEMF) is a high-speed forming method which simultaneously combines pulsed current heating and electromagnetic forming. The volumetric heating and electromagnetic forming are completed in microsecond timescale. DPCEMF can solve the forming difficulty for the materials with low conductivity and high strength, such as titanium alloy. The yield stress of titanium alloy sheet is reduced significantly due to the joule heat. The feasibility of the DPCEMF process was validated experimentally in this work. The effect of key parameters on the formation of a corrugated workpiece was investigated. The process window of corrugation workpiece of Ti-6Al-4 V titanium alloy with DPCEM method is proposed. The results show that it can realize the fine replication of the corrugation die and no oxidation occurrence of titanium alloy specimen. This is a consequence of the low flow stress with joule heat and uniform electromagnetic force with high-speed forming. [ABSTRACT FROM AUTHOR]

Quantum dots color conversion (QDCC) is considered as a facial and versatile way to achieve full-color organic light emitting diode (OLED) and micro-LED display due to the wide color gamut performance and easy integration. However, the aggregation of QDs and coffee-ring effects after solvent evaporation lowers the light conversion efficiency and emission uniformity in QDs microarrays, raising blue-light leakage or optical crosstalk. Here, we report the fabrication of perovskite quantum dots (PQDs) microarrays by combining the inkjet printing and in situ fabrication of PQDs during the photopolymerization of precursor ink. The resulting PQDs microarrays exhibit three-dimensional (3D) morphology with hemisphere shape as well as strong photoluminescence, which is desirable for QDCC applications. We demonstrate the dominant role of ultraviolet (UV) curable precursors and surface functionalized substrate in controlling the shape of microarrays, where significantly increased contact angle (100°) and large height to diameter ratio (0.42) can be achieved. We further demonstrate the potential use of the in situ direct print photopolymerization method for fabricating large-area multicolor patterned pixel microarrays with a wide color gamut and high resolution. The fabrication of 3D PQDs microarrays opens up new opportunities in a variety of applications including photonics integration, micro-LED, and near-field display. [ABSTRACT FROM AUTHOR]

Nitric oxide, ammonia and volatile organic compounds are common air pollutants which need to be removed for health security. To reach ultra-low emission standards, photocatalysis has emerged as a environmentally benign and efficient method to lower pollutant levels. Understanding the pollutant removal mechanism is necessary to optimize the design of the photocatalyst. Here, we review air purification by gas–solid photooxidation. We discuss the role of light absorption, charge carrier separation and active sites for designing the photocatalyst. We present reaction processes with emphasis on the adsorption and activation of reactants, the formation of intermediates and byproducts, and the conversion pathways towards the final product. Perspectives of photocatalytic degradation in suppressing by-products, inhibiting deactivation and dealing with pollutant mixtures are discussed. [ABSTRACT FROM AUTHOR]

Alluvial fans are an important land resource in the Qinghai-Tibet Plateau with the expansion of human activities. However, the factors of alluvial fan development are poorly understood. According to our previous investigation and research, approximately 826 alluvial fans exist in the Lhasa River Basin (LRB). The main purpose of this work is to identify the main influencing factors by using machine learning. A development index (Di) of alluvial fan was created by combining its area, perimeter, height and gradient. The 72% of data, including Di, 11 types of environmental parameters of the matching catchment of alluvial fan and 10 commonly used machine learning algorithms were used to train and build models. The 18% of data were used to validate models. The remaining 10% of data were used to test the model accuracy. The feature importance of the model was used to illustrate the significance of the 11 types of environmental parameters to Di. The primary modelling results showed that the accuracy of the ensemble models, including Gradient Boost Decision Tree, Random Forest and XGBoost, are not less than 0.5 (R2). The accuracy of the Gradient Boost Decision Tree and XGBoost improved after grid research, and their R2 values are 0.782 and 0.870, respectively. The XGBoost was selected as the final model due to its optimal accuracy and generalisation ability at the sites closest to the LRB. Morphology parameters are the main factors in alluvial fan development, with a cumulative value of relative feature importance of 74.60% in XGBoost. The final model will have better accuracy and generalisation ability after adding training samples in other regions. [ABSTRACT FROM AUTHOR]

Dicarboxylic acids are one of the important water-soluble organic compounds in atmospheric aerosols, causing adverse effects to both climate and human health. More attention has therefore been paid to organic acids in aerosols. In this study, the molecular distribution and diurnal variations of wintertime dicarboxylic acids in a rural site of Guanzhong Plain, Northwest China, were explored. Oxalic acid (C2, day: 438.9 ± 346.8 ng m−3, night: 398.8 ± 392.3 ng m−3) is the most abundant compound followed by methylglyoxal (mGly, day: 207.8 ± 281.1 ng m−3, night: 222.9 ± 231.0 ng m−3) and azelaic (C9, day: 212.8 ± 269.1 ng m−3, night: 211.4 ± 136.7 ng m−3) acid. The ratios of C9/C6 and C9/Ph indicating that atmospheric dicarboxylic acids in winter in the region mainly come from biomass burning. Furthermore, secondary inorganic ions (NO3−, SO42−, and NH4+), relative humidity, liquid water content, and in-situ pH of aerosols are highly linearly correlated with C2, suggesting that liquid phase oxidation is an important pathway for the formation of dicarboxylic acids. The δ13C analysis of C2 suggested that lighter carbon isotope compositions tend to be oxidized to form aqueous-phase secondary organic aerosols (aqSOA), leading to the decay of 13C in aqSOA products rather than aerosol aging. This study provides a theoretical basis for the mechanism of formation of dicarboxylic acid. [ABSTRACT FROM AUTHOR]

A turn-on fluorescent sensor based on CdTe quantum dots (QDs) is designed for highly sensitive and selective ascorbic acid (AA) detection. CdTe shows a strong emission centered at 578 nm. When assembled with poly(sodium 4-styrenesulfonate) (PSS) and methyl viologen (Mv2+) through electrostatic interaction, the emission is found to be effectively quenched. In the presence of AA, Mv2+ is reduced to Mv+, making the fluorescence of CdTe QDs restored. Under the optimal conditions, the proposed AA sensing method shows a linear proportional response from 0.8 µM to 20 µM, with the detecting limit as low as 50 nM. The developed method was successfully applied in the analysis of AA in human serum samples and cell lysates with satisfactory results. [ABSTRACT FROM AUTHOR]

Change detection is widely used in city construction, remote image detection, autonomous driving and so on. The most important challenge in change detection is how to define the real change, that is to say, how to detect the real changes while ignoring the unexpected changes? such as varying illumination, shadows, seasonal scene changes. Motivated by the key issue, in this paper, we propose a novel two-classified method that utilizes the depth information to assist the semantic information for better detecting changes. A gradual modification strategy is also designed to combine the high-level semantics and the low-level edge-sensitive features to achieve better depth estimation. The proposed framework was evaluated by using the VL-CMU-CD streetscape change detection dataset. Both quantitative and qualitative experiments have been implemented for evaluating the performance of the framework under different light and seasons. Experimental results show that the proposed method outperforms most of the current state-of-the-art results. [ABSTRACT FROM AUTHOR]

Type 2 diabetes mellitus (T2DM) patients have compromised mandibular bone architecture/quality, which markedly increase the risks of tooth loosening, tooth loss, and failure of dental implantation. However, it remains lacks effective and safe countermeasures against T2DM-related mandibular bone deterioration. Herein, we studied the effects of pulsed electromagnetic fields (PEMF) on mandibular bone microstructure/quality and relevant regulatory mechanisms in T2DM db/db mice. PEMF exposure (20 Gs, 15 Hz) for 12 weeks preserved trabecular bone architecture, increased cortical bone thickness, improved material properties and stimulated bone anabolism in mandibles of db/db mice. PEMF also upregulated the expression of canonical Wnt3a ligand (but not Wnt1 or Wnt5a) and its downstream β-catenin. PEMF improved the viability and differentiation of primary osteoblasts isolated from the db/db mouse mandible, and stimulated the specific activation of Wnt3a/β-catenin signaling. These positive effects of PEMF on mandibular osteoblasts of db/db mice were almost totally abolished after Wnt3a silencing in vitro, which were equivalent to the effects following blockade of canonical Wnt signaling using the broad-spectrum antagonist DKK1. Injection with Wnt3a siRNA abrogated the therapeutic effects of PEMF on mandibular bone quantity/quality and bone anabolism in db/db mice. Our study indicates that PEMF might become a non-invasive and safe treatment alternative resisting mandibular bone deterioration in T2DM patients, which is helpful for protecting teeth from loosening/loss and securing the dental implant stability. [ABSTRACT FROM AUTHOR]

Adhesively bonded sandwich structure with dissimilar materials becomes an important means of lightweight for the next generation of autobody closure panels. However, during the baking process, the complicated change of physical properties of the adhesive can lead to structural mismatch deformation. In this paper, a multi-physics coupling numerical model of the curing process is proposed to reveal the deformation mechanism of adhesively bonded sandwich structures quantitatively. The material constitutive model of the one-component hemming adhesive hemming adhesive is established, considering evolution of curing properties. The curing process of typical aluminum alloy and steel-bonded sandwich structure is simulated in COMSOL Multiphysics. The predicted surface deformation of the component is verified by experiment using Digital Image Correlation (DIC) technique, which captures the full-field displacement in a non-intrusive manner. Then, the development process of surface deformation of the outer panel and residual internal stress of the adhesive layer is analyzed, and the influence of temperature cycle on the maximum deformation of the component is discussed. The results show that at the beginning of holding stage, the deformed component slightly rebounds, which is related to the chemical shrinkage. Mechanical strain caused by the coefficient of thermal expansion (CTE) and stiffness difference of the inner and outer panels is dominant in the adhesive layer. Reducing the curing rate and maximum holding temperature can reduce the overall deformation of the structure. [ABSTRACT FROM AUTHOR]

Incompatible polypropylene (PP) and polyethylene (PE) are difficult to separate in mixed recycling streams such as waste plastic packaging, which makes polyolefin mixtures unsuitable for high-quality products. In this work, based on the free radical branching reaction, a co-branching reaction of isotactic polypropylene (iPP) and high-density polyethylene (HDPE) blends was carried out in the presence of the peroxide, free radical regulator and multifunctional acrylate monomer, and a star-like long-chain branching (LCB) copolymer was obtained. The effect of in situ compatibilization on the structures and mechanical properties of iPP/HDPE was investigated, and the compatibilization mechanism was discussed. Results showed that the mechanical properties of the modified blends were largely improved, and efficient in-situ compatibilization of iPP and HDPE could be taken place in a wide process window. Moreover, the sizes of the dispersed phase in the modified blends were clearly decreased, and the interfacial thickness increased. Compared with the pure iPP/HDPE blend, the initial crystallization temperature of iPP in the modified iPP/HDPE blend was increased, and long branched chains of the LCB copolymers were physically entangled with the chemical identical homopolymers or even participated in the crystallization of iPP and HDPE. Thanks to the in situ compatibilization strategy, the compatibility of iPP/HDPE was significantly improved. [ABSTRACT FROM AUTHOR]