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Utilization of metal tungsten (W) as the structural material or pressure scale requires accurate knowledge of the equation of state (EOS), which is far beyond the available experimental measurements. In the present work, a direct integral approach (DIA) with ultrahigh efficiency was applied to calculate the EOS of W up to 500 GPa and 3000 K with ab initio calculations. Compared with previous static compression experiments up to 150 GPa under room temperature and 35 GPa at high temperatures up to 1673 K, all the deviations of the calculated pressure are within or comparable to the uncertainty of experiments. Predictions for higher-temperature and simultaneously higher-pressure EOS up to 300 GPa and 3000 K differ slightly from the comprehensive analysis by Litasov et al. [J. Appl. Phys. 113, 133505 (2013)] via fitting available experimental data with the empirical equation. These results indicate that the EOS of crystal W obtained from DIA should be convincible, and DIA without any empirical or artificial parameters may find its wide applications for predicting thermodynamic properties of condensed matter in the future. [ABSTRACT FROM AUTHOR]

AbstractObjectiveMethodsResultsConclusionTo analyze the effectiveness of stent retriever mechanical thrombectomy combined with tirofiban in treating acute ischemic stroke.Markedly effective is defined as an SIS score of over 90, effective is indicated by an SIS score of between 50–90, and a score of below 50 suggests ineffective treatment results.①The treatment’s overall effectiveness in the observation group (91.30%) was significantly higher than that in the control group (75.56%) (p < 0.05). ②The vascular recanalization rate in the observation group (89.13%) was significantly higher than that in the control group (71.11%) (p < 0.05). ③The stent retrieval operation count (2.41 ± 0.23) was significantly lower in the observation group than in the control group (1.29 ± 0.16) (p < 0.05). ④ After treatment, the platelet aggregation rate (10.74 ± 3.95) and NIHSS scores (6.58 ± 1.04) were significantly lower, and the Barthel index (77.86 ± 7.21) was significantly higher in the observation group compared to the control group (26.47 ± 5.12, 7.75 ± 2.36, 68.12 ± 6.15) (p < 0.05). All platelet aggregation rate, NIHSS scores and Barthel Index showed significant improvement after treatment when compared to those before treatment (p < 0.05).The combined application of stent retriever mechanical thrombectomy and tirofiban in acute ischemic stroke treatment shows promising effectiveness. Compared to stent retriever alone, tirofiban adjunctive therapy enhances vascular recanalization, reduces retrieval procedures, shortens treatment duration, inhibits platelet aggregation, and improves neurological function recovery, daily living activities, and prognosis. Moreover, it doesn’t significantly increase symptom-related risks. [ABSTRACT FROM AUTHOR]

Tunnel boring machines (TBMs), excavation tools for tunnel construction, often struggle to penetrate extremely hard rock formations. This study proposes an innovative solution to enhance the construction efficiency of TBMs in such environments: a microwave-assisted TBM cutter. In our experiments, we irradiated basalt samples with 3 kW microwaves for varying durations. We conducted a full-scale rock-breaking experiment using the multifunctional rock-breaking platform at Central South University, China. We then compared the cutting force, cutting coefficient, and specific energy consumption of the cutter at different processing times. Our results indicate that microwave pretreatment can effectively reduce both the cutting force and specific energy consumption of rock. Furthermore, under certain cutting force conditions, the quantity of rock broken can be significantly increased with extended microwave irradiation. However, we found a critical threshold for the processing time of 3 kW microwave-assisted rock breaking. Beyond this threshold, the specific energy consumption of rock breaking is not significantly reduced. For a microwave processing time of 16 min, the optimal ratio of cutter spacing to penetration (s/p) is 16.7. The findings of this study offer valuable insights and guidance for TBM construction operations in extremely hard-rock environments. [ABSTRACT FROM AUTHOR]

The contributions of deeply subducted slabs to post-collisional magmatism are poorly constrained. Here, we present a study of the post-collisional, Early Permian (ca. 279 Ma), Hamisite basalts from the Western Tianshan NW China to trace the geochemical fingerprints of deeply subducted slab. The Hamisite basalts have arc-like trace element patterns but high Nb/Ta ratios (18.4-23.0). They have slightly enriched Sr--Nd isotopic compositions (87Sr/86Sr = 0.7048-0.7052; εNd[t] = 2.02--3.85), which indicates that the basalts were derived from an enriched mantle source. Extremely low δ7Li values (-5.76‰ to 0.20‰) imply the involvement of a deeply subducted slab (i.e., eclogites) in the source. Correlations among Nb/Ta and (Dy/Yb)N ratios, and rare earth element contents, indicate that the deeply subducted slab contained residual rutile and garnet but no epidote. Given that melting of eclogites requires an anomalously hot mantle source, we propose that mantle upwelling during post-collisional extension triggered melting of the deeply subducted slab. Our results indicate that melting of a deeply subducted slab can generate a metasomatized mantle source with high Nb/Ta ratios, which could be a hidden, high-Nb/Ta reservoir on Earth. Low δ7Li values and high Nb/Ta ratios could be a fingerprint of recycling of a deeply subducted slab. [ABSTRACT FROM AUTHOR]

To initially improve the gas production rate and shorten the payback period for tight gas reservoirs, the multiple-fractured horizontal well (MFHW) model is always applied. However, in the late stages of exploitation, it is difficult to adopt reasonable measures for enhanced gas recovery (EGR), particular for continental sedimentary formation with multiple layers, and efficient strategies for EGR in this type of gas field have not yet been presented. Therefore, in this paper, a typical tight gas reservoir in the late stages of exploitation, the Denglouku gas reservoir in Changling gas field, in which MFHWs were utilized and contributed to the communication of the higher Denglouku formation (0.34 mol% CO2) and lower Yingcheng formation (27 mol% CO2) during hydraulic fracturing, is studied comprehensively. Firstly, alongside the seismic, logging, drilling and experimental data, 3D geological and numerical simulation models are developed. According to the differences in CO2 mole fractions for different formations, the gas production rate of MFHWs produced from Denglouku formation is accurately calculated. Then, the well gas production rate (WGPR) and the well bottom-hole pressure (WBHP) history are matched with the calculated values, and thus the types of remaining gas are provided through the fine reservoir description. Finally, in a combination of gas recovery and economics, the optimal infill well type and the adjustment scheme are determined. The results show that there are three main categories of remaining gas, which are areal distribution, abundant points, and marginal dispersion, and the ratios of reaming gas reserve for these three types are 80.3%, 4.2%, and 15.5%, respectively. For the tight gas reservoir developed by MFHWs with parallel and zipper patterns, the best infilling well type is the vertical well. The combination of patching holes, sidetracking, infilling and boosting can obtain the highest gas recovery, while the scheme with patching holes and sidetracking has the best economic benefits. To balance the gas recovery and economics, the measurement of patching holes, sidetracking and infilling with vertical wells is utilized. In the final production period, compared with the basic schemes, the gas recovery can increase by 5.5%. The primary novelty of this paper lies in the determination of the optimal infilling well types and its presentation of a comprehensive adjustment workflow for EGR in tight gas reservoirs. The conclusions in this paper can provide some guidance for other similar tight gas reservoirs developed with MFHWs in the later period. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of gas mixture components on the combustion characteristics of rotating detonation wave, two-dimensional simulation is presented to simulate the propagation process of rotating detonation wave with different methane conversions. The results indicate that there are five propagation modes of rotating detonation wave with different components: single-wave mode, single wave with counter-rotating components mode, double-waves mode, triple-waves mode and quadruple-waves mode. The detonation wave propagates along the forward direction in all five modes. With the increase of methane conversion, multi-wave mode appears in the combustion chamber. The fuel component has a great influence on the heat release ratio of detonation combustion. The velocity of detonation wave decreases with the increase of methane conversion. With the increase of methane conversion, the chemical reaction rate gradually increases, which leads to the intensification of chemical reaction on the deflagration surface. The reaction on the deflagration surface develops to the unburned fuel zone, which eventually leads to the formation of compression waves and shock waves in the fuel refill zone. When the shock wave sweeps through the fresh premixed gas, the reactant is compressed to form a detonation point and then ignite the fuel. A new detonation wave is finally formed. The total pressure ratio decreases with the increasing methane conversion, and the uniformity of the total pressure of outlet decreases with increasing methane conversion. • Component change of multicomponent mixture dictate propagation mode. • The influence of component change on detonation wave velocity and pressure is revealed. • The effect of deflagration surface reaction on the characteristics of detonation wave is analyzed. • Pressure ratio of combustion chamber with mixture of different components is compared. [ABSTRACT FROM AUTHOR]

As the counterpart of classical theorems on cycles of consecutive lengths due to Bondy and Bollobás in spectral graph theory, Nikiforov proposed the following open problem in 2008: What is the maximum C $C$ such that for all positive ε⌊n24⌋ $\rho (G)\gt \sqrt{\lfloor \frac{{n}^{2}}{4}\rfloor }$ contains a cycle of length ℓ $\ell $ for each integer ℓ∈[3,(C−ε)n] $\ell \in [3,(C-\varepsilon)n]$. We prove that C≥14 $C\ge \frac{1}{4}$, improving the existing bounds. Besides several novel ideas, our proof technique is partly inspired by the recent research on Ramsey numbers of star versus large even cycles due to Allen, Łuczak, Polcyn, and Zhang, and with aid of a powerful spectral inequality. We also derive an Erdős–Gallai‐type edge number condition for even cycles, which may be of independent interest. [ABSTRACT FROM AUTHOR]

BACKGROUND: School principals usually have to sacrifice health and family obligations to obtain sufficient work time. This study investigates school principals' somatic and psychological discomfort related to their time allocation to diverse work contexts and life domains, so as to test the optimal allocation of time to each context and domain. METHODS: This study is based on survey data of 347 school principals, from the preexisting 2021 Survey of School Teachers' Living Conditions in Shanghai. Generalized linear regression modeling was adopted to analyze the data according to the research purpose. RESULTS: This study finds that school principals' daily time spent on work at home, sleep, breakfast, exercise, and family obligations significantly predict their somatic or psychological discomfort. However, their time spent on work at school, daytime napping, lunch, and dinner are not of significance. CONCLUSIONS: This study reveals several unhealthy ways of working and lifestyle habits among school principals from a perspective of time allocation, such as extended periods working at home, sleep deficits, hurried breakfast, lack exercise, and failure to meet familial obligations. [ABSTRACT FROM AUTHOR]

Multi-turn dialogue generation is an essential and challenging subtask of text generation in the question answering system. Existing methods focused on extracting latent topic-level relevance or utilizing relevant external background knowledge. However, they are prone to ignore the fact that relying too much on latent aspects will lose subjective key information. Furthermore, there is not so much relevant external knowledge that can be used for referencing or a graph that has complete entity links. Dependency tree is a special structure that can be extracted from sentences, it covers the explicit key information of sentences. Therefore, in this paper, we proposed the EAGS model, which combines the subjective pivotal information from the explicit dependency tree with sentence implicit semantic information. The EAGS model is a knowledge graph enabled multi-turn dialogue generation model, and it doesn't need extra external knowledge, it can not only extract and build a dependency knowledge graph from existing sentences, but also prompt the node representation, which is shared with Bi-GRU each time step word embedding in node semantic level. We store the specific domain subgraphs built by the EAGS, which can be retrieved as external knowledge graph in the future multi-turn dialogue generation task. We design a multi-task training approach to enhance semantics and structure local feature extraction, and balance with the global features. Finally, we conduct experiments on Ubuntu large-scale English multi-turn dialogue community dataset and English Daily dialogue dataset. Experiment results show that our EAGS model performs well on both automatic evaluation and human evaluation compared with the existing baseline models. [ABSTRACT FROM AUTHOR]

The hardness of high‐strength steel gradually decreases from the subsurface layer to the layer that is half its thickness. This hardness distribution reduces the wear resistance of steel plates. To date, there have been few reported solutions to this problem. Herein, an in situ approach is used to prepare TiC‐reinforced steel. The findings demonstrate that the introduction of TiC reinforcement enhances the wear resistance performance along the thickness direction of high‐strength steel. Although the hardness of TiC‐reinforced steel gradually decreases from the surface to the core, the wear resistance of the steel initially increases before decreasing. In addition, compared with normal steel, the wear resistance performance of TiC‐reinforced steel is increased by 15% at the subsurface, 24% at 1/4 thickness, and 31% at 1/2 thickness. This unusual phenomenon is attributed to the size features of TiC, which vary along the thickness of the plate. The proportion of small TiC particles decreases from the subsurface layer to the core, whereas the proportion of large TiC particles increases gradually. This technique can provide an avenue for improving the wear resistance of other large‐thickness wear‐resistant materials along the thickness direction. [ABSTRACT FROM AUTHOR]

A heterogeneous photocatalytic 3-trifluoromethylation and 3-perfluoroalkylation of 4-aminocoumarins was realized from 4-aminocoumarins and CnF2n+1SO2Na under mild conditions using mesoporous graphitic carbon nitride (mpg-C3N4) as an effective and recyclable photocatalyst without any other additives. This transition-metal-free procedure shows wide substrate scope with air as a green oxidant affording 3-trifluoromethylated/perfluoroalkylated 4-aminocoumarins in moderate to good yields. [ABSTRACT FROM AUTHOR]

Background: Desmoid tumor (DT), also known as desmoid-type fibromatosis (DTF) or aggressive fibromatosis (AF) is a rare mesenchymal tumor affecting both children and adults. It is non-metastasis but infiltrative, growing with a high recurrence rate to even cause serious health problems. This study investigates the biology of desmoid tumors through integrated multi-omics studies. Methods: We systematically investigated the clinical data of 98 extra-abdominal cases in our pediatric institute and identified some critical clinical prognostic factors. Moreover, our integrated multi-omics studies (Whole Exome Sequencing, RNA sequencing, and untargeted metabolomics profiling) in the paired PDT tumor/matched normal tissues identified more novel mutations, and potential prognostic markers and therapeutic targets for PDTs. Results: The top mutation genes, such as CTNNB1 (p.T41A and p.S45F) and MUC4 (p.T3775T, p.S3450S, etc.), were observed with a mutation in more than 40% of PDT patients. We also identified a panel of genes that are classed as the FDA-approved drug targets or Wnt/β-catenin signaling pathway-related genes. The integrated analysis identified pathways and key genes/metabolites that may be important for developing potential treatment of PDTs. We also successfully established six primary PDT cell lines for future studies. Conclusions: These studies may promote the development of novel drugs and therapeutic strategies for PDTs. [ABSTRACT FROM AUTHOR]

As an unconventional clean resource with huge reserves and a wide distribution, natural gas hydrates (NGHs) have good application prospects. However, due to limited understanding and available production technology for NGHs, there is still a large gap between current production tests and commercial exploitation. A breakthrough in reservoir stimulation technologies is key to realizing the industrialization of NGHs in the future. Through a comprehensive summary of hydrate production test cases in Japan and China, this paper highlights the difficulties in the transformation of weakly-consolidated reservoirs. By systematically reviewing the theory and technology of hydrate reservoir transformation and engineering applications, this paper elucidates in detail the technical principles and mechanisms of several available stimulation technologies for weakly-consolidated reservoirs, and assesses the feasibility of their application to increase the production of NGHs. Existing problems and challenges are summarized and future prospects are discussed. Finally, suggestions are put forward for research and development of transformation technology for weakly-consolidated NGHs reservoirs in the future. [ABSTRACT FROM AUTHOR]

Anxiety or depression after percutaneous coronary intervention (PCI) is a common clinical disease. Currently, conventional pharmacotherapy primarily involves the administration of anxiolytic or antidepressant medications in conjunction with anticoagulants, antiplatelet agents, and other cardiovascular drugs. However, challenges such as drug dependence, adverse reactions and related concerns persist in the treatment of this disease. Numerous pertinent studies have demonstrated that Traditional Chinese Medicine (TCM) exhibits significant therapeutic efficacy and distinctive advantages in managing post-PCI anxiety or depression. This review attempted to summarize the characteristics of TCM for treating anxiety or depression after PCI, including single Chinese herbs, Chinese medicine monomers, compound TCM prescriptions, TCM patented drugs, and other TCM-related treatment methods, focusing on the analysis of the relevant mechanism of TCM treatment of this disease. By searching the literature on treating anxiety or depression after PCI with TCM in PubMed, Web of Science, CNKI, and other relevant databases, this review focuses on the latest research progress of TCM treatment of this disease. In the treatment of anxiety or depression after PCI, TCM exerts significant pharmacological effects such as anti-inflammatory, antioxidant, anti-anxiety or anti-depression, cardiovascular and cerebrovascular protection, and neuroprotection, mainly by regulating the levels of related inflammatory factors, oxidative stress markers, neurotransmitter levels, and related signaling pathways. TCM has a good clinical effect in treating anxiety or depression after PCI with individualized treatment. TCM has terrific potential and good prospects in the treatment of anxiety or depression after PCI. The main direction of future exploration is the study of the mechanism related to Chinese medicine monomers and the large sample clinical study related to compound TCM prescriptions. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Although low-temperature photothermal therapy (PTT) can sensitize tumors to immune checkpoint inhibition, its efficacy is still restricted in the deep and internal tumors without enough oxygen and lymphocytic infiltration. Non-oxygen-dependent alkyl radicals have been demonstrated to synergistically enhance PTT through up-regulating lipid peroxidation and reactive oxygen species (ROS). Herein, an innovative strategy based on alkyl radicals to augment immunogenetic cell death (ICD) caused by mild PTT was proposed to improve poor efficacy of immunotherapy, which composed of a photothermal material of Chinse ink, an azo-initiator of 2,2-azobis[2-(2- imidazoline -2- acyl) propane ]dihydrochloride (AIPH) and a PD-L1 inhibitor of HY19991 (HY). Upon near-infrared-II laser irradiation, low-temperature (<45℃) stimulation induced a high expression of immune checkpoint receptor (PD-L1) in tumors and triggered a large amount alkyl radicals generated by AIPH. Significantly, the alkyl radicals augmented the ICD and increased the recruitment of tumor-infiltrating lymphocytes against tumors after transformation of the immunologically cold tumor microenvironment into hot by mild PTT. The released HY further enhanced the immunotherapy effect by blocking the binding of activated T lymphocytes and PD-L1. In vivo studies exhibited that the all-in-one hydrogel with synergistic mechanisms had an extraordinary ability to reverse the immunosuppressive microenvironment, stimulate innate and adaptive immune responses to eliminate tumors and prevent metastasis. [ABSTRACT FROM AUTHOR]

This article explored the different clusters of leadership styles and the relationship between principal leadership style and student academic achievement in domains of mathematics, reading, science, and collaborative problem-solving in Germany and China. We used PISA 2015 data covering 6,504 students and 256 school principals from German schools and 9,841 students and 268 school leaders from Chinese schools. Results identified three leadership styles in Germany, namely, transformational (23.4%), instructional (41.3%), and integrated (35.3%) leadership, and two leadership styles in China, namely, transformational (38.6%) and instructional (61.4%) principals. Principals with instructional and integrated leadership had higher student achievements in Germany, whereas only principals with transformational leadership had slightly higher student achievements in China. Moreover, three leadership styles in Germany and two in China showed their relationships with each domain of student achievement. In conclusion, principals in Germany and China had different priorities in leading schools. The differences that principal leadership made on student achievements highlighted the differences in principals' situational context and leading characteristics between Germany and China. [ABSTRACT FROM AUTHOR]

Heterostructural engineering of atomically thin 2D materials offers an exciting opportunity to fabricate atomically sharp interfaces for optoelectronic devices. Herein, GeSe/WS2 heterojunction devices composed of 2D WS2 (n‐type) and few‐layer GeSe (p‐type), are fabricated by transferring mechanically exfoliated GeSe to chemical vapor deposition (CVD)‐grown WS2. Excellent rectification behavior is observed from the I−V characteristics of the GeSe/WS2 heterojunction devices. The reverse photocurrent increases more rapidly than the forward photocurrent under a 635 nm laser illumination, indicating an effective separation of the photogenerated carriers under a minus bias. A large photocurrent on‐off ratio of 103 at −5 V bias, a high responsivity (Rλ) of 1.1 A W−1, a considerable specific detectivity (D*) of 1.3×1010 Jones, and a high external quantum efficiency (EQE) of 214.8%, are obtained. Owing to the large built‐in potential of the heterojunction, efficient charge transfer is achieved from the abrupt interfaces even though vastly different materials are used in the van der Waals (vdW) heterostructure. A convenient route is demonstrated for the preparation of ultra‐thin GeSe/WS2 vdW heterojunctions. The results reveal great potential of the present GeSe/WS2 vertical heterojunction for future applications in optoelectronics. [ABSTRACT FROM AUTHOR]

This research was aimed at investigating the artificial intelligence (AI) segmentation algorithm-based multislice spiral computed tomography (MSCT) in the diagnosis of liver cirrhosis and liver fibrosis. Besides, it was aimed at providing new methods for the diagnosis of liver cirrhosis and liver fibrosis. All patients were divided into the control group, mild liver fibrosis group, and significant liver fibrosis group. A total of 112 patients were included, with 40 cases in the mild liver fibrosis group, 48 cases in the significant liver fibrosis group, and 24 cases who underwent computed tomography (CT) examination in the control group. In the research, deconvolution algorithm of AI segmentation algorithm was adopted to process the images. The average hepatic arterial fraction (HAF) values of patients in the control group, mild liver fibrosis group, and severe liver fibrosis group were 17.59 ± 10.03 %, 18.23 ± 5.57 %, and 20.98 ± 6.63 %, respectively. The average MTT values of patients in the control group, mild liver fibrosis group, and severe liver fibrosis group were 12.69 ± 1.78 S, 12.53 ± 2.05 S, and 12.04 ± 1.57 S, respectively. The average blood flow (BF) values of patients in the control group, mild liver fibrosis group, and severe liver fibrosis group were 105.68 ± 15.57 mL 100 g-1·min-1, 116.07 ± 16.5 mL·100 g-1·min-1, and 110.39 ± 16.32 mL·100 g-1·min-1, respectively. Besides, the average blood volume (BV) values of patients in the control group, mild liver fibrosis group, and significant liver fibrosis group were 15.69 ± 4.35 mL·log-1, 16.97 ± 2.68 mL·log-1, and 16.11 ± 4.87 mL·100 g-1, respectively. According to statistics, the differences among the average HAF, MTT, BF, and BV values showed no statistical meaning. AI segmentation algorithm-based MSCT imaging could promote the diagnosis of liver cirrhosis and liver fibrosis effectively and offer new methods to clinical diagnosis of liver cirrhosis and liver fibrosis. [ABSTRACT FROM AUTHOR]

• An approach is proposed for identification of bridge bending stiffness distribution using improved Gaussian peak function. • The improved Gaussian peak function allows for considering a wider range of stiffness variation models and thus is a general model. • The Levenberg-Marquardt (LM) method is proposed for parameter estimation and shows good robustness with different initial parameter values. • Numerical simulation and laboratory experiment are used to verify the effectiveness of the proposed method in identifying bridge bending stiffness distribution. Bridge damage and bending stiffness deterioration can lead to a decrease in the bearing capacity of a bridge, posing significant safety concerns. To ensure the safe operation of bridges, it is crucial to accurately identify bending stiffness deterioration and assess the bridge performance. The bridge influence line (IL), which reflects the deterioration of bending stiffness, was widely used in the assessment of bending stiffness deterioration. Existing IL-based methods mostly assume a uniform reduction in bending stiffness for identification. In reality, the deterioration of bridge bending stiffness is far more complex, which causes difficulty in accurately identifying the bending stiffness distribution using the uniform reduction model. This paper proposes a novel method for identifying bridge stiffness distribution using an improved Gaussian peak function model. The improved model incorporates additional parameters, allowing for considering a wider range of stiffness variation and thus addressing the limitations of traditional models. The parameters of the improved Gaussian peak function model are estimated by minimizing the residual between the predicted deflection influence line (DIL) and the actual DIL using the Levenberg-Marquardt (LM) algorithm. This approach enables the accurate identification of bending stiffness distribution without baseline information. Numerical simulation and laboratory experiment are used to verify the effectiveness of the proposed method in identifying bridge bending stiffness distribution. A comparison between the identified and actual bending stiffness distribution curves under various forms of damage assesses the applicability of the proposed method. [ABSTRACT FROM AUTHOR]

Limited microscopic simulation models focus on pedestrian movements at signalized intersections, and fewer studies still pay attention to their jaywalking. This paper tries to fill this gap by establishing a microscopic simulation model for pedestrians and vehicles, which can include pedestrians' jaywalking. The acceptable gap theory model and the social force model are modified to develop this model. The model parameters are calibrated using observed speed and trajectory data. Finally, the model performance is verified using both a macroscopic and a microscopic approach. Crossing speeds, crossing positions, the crossing process, conflicts between pedestrians and vehicles, trajectories and their distribution are all analyzed. Based on this research, a countermeasure is proposed to limit pedestrians' jaywalking, and its effectiveness is analyzed through field and simulation experiments. The contrasting results of the simulation and observed data indicate that the proposed model can visually reproduce the crossing behaviors of pedestrians at signalized intersections. [ABSTRACT FROM AUTHOR]

As a promising dielectric material, tantalum pentoxide (Ta2O5) exhibits multi‐phase co‐existing under common fabrication conditions, so it is highly desired to predict theoretically which phase is of the largest dielectric constant. Considering that the specific operations and parameters employed in ab initio calculations may lead to considerably different lattice structure, we set the experimental lattice constants as the criteria to select the functional and parameters in density of functional theory and calculated the dielectric tensors of crystalline δ‐, β‐, LSR‐, B‐, and Z‐Ta2O5, showing that the dielectric constant is very sensitive to the lattice constants and δ‐Ta2O5 possesses the largest dielectric constant, 375.1, which is about 10 times larger than those of the other four phases and the experimental measurement of common Ta2O5 samples with several phases co‐existed, and furthermore, the dielectric constant of δ‐ and β‐Ta2O5 could be enhanced to 1175.2 and 939.5, respectively, with the Ta atom replaced by Ti atom at a molar ratio of 7.14%, which is in qualitative agreement with the experimental observations of Ti‐doped β‐, LSR‐, and H‐Ta2O5. [ABSTRACT FROM AUTHOR]

The bipartite Turán number, denoted by ex(m,n,H), is the maximum number of edges in an H‐free bipartite graph with two parts of sizes m and n, respectively. In this article, we prove ex(m,n,C2t)=(t−1)n+m−t+1 for any positive integers m,n,t with n≥m≥t≥m2+1, which confirms (in a strong form) the unsolved case of a conjecture of Győri. Let G=(X,Y;E) be a bipartite graph with ∣X∣=n and ∣Y∣=m. Suppose that n≥m≥2k+2 for some k∈N. We prove that G contains cycles of all even lengths from 4 to 2m−2k if e(G)≥(m−k−1)n+k+2. This result sharpens a theorem on long cycles in bipartite graphs due to Jackson. As a main tool, for a longest cycle C in a bipartite graph, we prove an upper bound of the number of edges which are incident with at most one vertex in C, which is a bipartite analogue of a classical theorem of Bondy. Our proof technique is structural. [ABSTRACT FROM AUTHOR]

In 1990, Cvetković and Rowlinson conjectured that among all outerplanar graphs on n vertices, K1∨Pn−1 attains the maximum spectral radius. In 2017, Tait and Tobin confirmed the conjecture for sufficientlty large values of n. In this article, we show the conjecture is true for all n≥2 except for n=6. [ABSTRACT FROM AUTHOR]

In petroleum seismic exploration, dense seismic ray coverage is often guaranteed through dense seismic sources and geophones. Dense ray coverage facilitates the high-resolution 3D velocity structure imaging of near surfaces using surface waves. In this study, the 3D velocity and anisotropy structure of a petroleum exploration area are obtained using the azimuth-dependent dispersion curve inversion (ADDCI) method. Imaging results show that low-velocity zones correspond to a river channel. The fast propagation direction (FPD) of S-waves along this channel is basically consistent with the direction of the channel. The eastern part of the study area has a surface sediment layer with a thickness of less than 20 m, which corresponds to the sand and gravel deposits formed by the river alluvial deposition near the surface. In addition, a relatively thick sedimentary layer is formed on the southern side of the study area. The anisotropy shows that the FPD is positively correlated with the direction of alluvial flow and that the magnitude of anisotropy in the deep part is greater than that in the shallow part. Inversion results are basically consistent with the geological data and suggest that the obtained model can truly reflect the 3D velocity structure and anisotropy of the near-surface area. This study shows that the ADDCI method can maximize the high-energy surface waves in exploration data to obtain near-surface velocity structures, which provide a highly accurate model for near-surface static correction. [ABSTRACT FROM AUTHOR]

Background: A number of studies have shown the positive effects of acupuncture on state anxiety. However, the efficacy of acupuncture in treating anxiety disorder remains unclear. This review and meta-analysis aimed to explore whether acupuncture has a positive effect on anxiety disorder. Methods: Randomised controlled trials (RCTs) published in English and Chinese were found through various electronic databases, including PubMed, Scopus, the Cochrane Central Register of Controlled Trials, Embase, and the Chinese databases WanFang data, VIP Chinese Sci tech periodical database, and China National Knowledge Infrastructure. The primary outcome variable was extent of anxiety symptoms. The secondary outcomes included side effects and dropout rate. Effect sizes were pooled by random-effects modelling using Rev Man 5.3. Results: Twenty RCTs were included in this systematic review and meta-analysis. All included studies were designed for patients with generalised anxiety disorder (GAD), and 18 studies were published in Chinese. Egger's test showed that the asymmetry of the funnel plot in all studies was not significant (t = − 0.34, p = 0.74). The meta-analysis of anxiety symptoms showed that acupuncture was more effective than the control condition, with a standard mean effect size of − 0.41 (95% CI − 0.50 to − 0.31; p < 0.001), and that acupuncture intervention showed good tolerance and safety in the treatment of anxiety disorder. Conclusion: Our findings suggest that acupuncture therapy aimed at reducing anxiety in patients with GAD has certain beneficial effects compared to controls. More RCTs with high quality should be conducted to fully understand the role of acupuncture in the treatment of various types of anxiety disorder. The protocol of this review was registered at the Prospero International Prospective Register of Systematic Reviews (Registration ID: PROSPERO 2020CRD42020148536). [ABSTRACT FROM AUTHOR]

For a 2-connected graph G on n vertices and two vertices x , y ∈ V (G) , we prove that there is an (x , y) -path of length at least k , if there are at least n − 1 2 vertices in V (G) \ { x , y } of degree at least k. This strengthens a celebrated theorem due to Erdős and Gallai in 1959. As the first application of this result, we show that a 2-connected graph with n vertices contains a cycle of length at least 2 k , if it has at least n 2 + k vertices of degree at least k. This confirms a 1975 conjecture made by Woodall. As other applications, we obtain some results which generalize previous theorems of Dirac, Erdős-Gallai, Bondy, and Fujisawa et al., present short proofs of the path case of Loebl-Komlós-Sós Conjecture which was verified by Bazgan et al. and a conjecture of Bondy on longest cycles (for large graphs) which was confirmed by Fraisse and Fournier, and make progress on a conjecture of Bermond. [ABSTRACT FROM AUTHOR]

A matching M in a graph G is a set of disjoint edges of G. The matching number ν (G) is the number of edges in a maximum matching of G. The number of cliques of size s in G is denoted by N s (G). Given positive integers n , k , and r , the graph H (n , k , r) is the one obtained from K 2 k + 1 − r by connecting each vertex of an independent set of size n − (2 k + 1 − r) to the same r vertices chosen from K 2 k + 1 − r. Set h s (n , k , r) = N s (H (n , k , r)) = 2 k + 1 − r s + (n − 2 k − 1 + r) r s − 1 . In 1959, Erdős and Gallai proved that if G is a graph with n ≥ 2 k + 2 vertices and ν (G) ≤ k , then e (G) ≤ max { 2 k + 1 2 , h 2 (n , k , k) } and characterized the extremal graphs. In this paper, motivated by a question proposed by Füredi, Kostochka, and Luo, we first extend Erdős and Gallai's result. To be precisely, we prove that if G is a graph with n ≥ 2 k + 2 vertices, minimum degree δ , and ν (G) ≤ k , then N s (G) ≤ max { h s (n , k , δ) , h s (n , k , k) } for each s ≥ 2. Moreover, we are able to prove stability versions of this result specialized to edges. Namely, we prove if e (G) > max { h 2 (n , k , δ) , h 2 (n , k , k − 2) } and n ≥ 2 k + 2 , then G is a subgraph of H (n , k , k) or H (n , k , k − 1). If e (G) > max { h 2 (n , k , δ + 2) , h 2 (n , k , k) } and n ≥ 2 k + 11 , then G is a subgraph of H (n , k , δ) or H (n , k , δ + 1). [ABSTRACT FROM AUTHOR]

Utilizing the Programme for International Student Assessment 2012 Shanghai dataset (N = 5 , 177), this study examined the relationship between school disciplinary climate aggregated from mathematics classrooms and student mathematics learning outcomes, including mathematics achievement and intrinsic and instrumental motivation to learn mathematics, from the perspective of the self-determination theory of academic motivation. The results of the analyses demonstrated challenges supporting students in Shanghai schools to simultaneously perform well in the three mathematics learning outcomes. Meanwhile, an orderly school disciplinary climate might hurt students' instrumental motivation, although it is beneficial to students' mathematics achievement. [ABSTRACT FROM AUTHOR]

In this paper, we first present spectral conditions for the existence of C n − 1 in graphs (2-connected graphs) of order n, which are motivated by a conjecture of Erd ő s. We also prove spectral conditions for the existence of Hamilton cycles in balanced bipartite graphs. This result presents a spectral analog of Moon-Moser's theorem on Hamilton cycles in balanced bipartite graphs, and extends a previous theorem due to Li and the second author for n sufficiently large. We conclude this paper with two problems on tight spectral conditions for the existence of long cycles of given lengths. [ABSTRACT FROM AUTHOR]

To investigate the matching rules of cutters with different blade widths in hard rock and extremely hard rock environments, this study carries out a full-scale cutting test of 432-mm disc cutters with blade widths of 12 mm, 19 mm and 30 mm. A multifunctional cutter performance experimental system was used to test the cutting loads and rock-breaking quantity of rust stone granite (hereinafter referred to as hard rock) and granite (hereinafter referred to as extremely hard rock) as well as to analyse the specific energy consumption for rock breaking under different cutting parameters. The experimental results show that (1) the blade width has a greater influence on the normal force than on the rolling force. The rock-breaking resistance of the 12-mm-blade-width cutters under extremely hard rock conditions is 36.7% lower than that of conventional cutters. (2) Under the same conditions, the smaller the blade width is, the smaller the specific rock-breaking energy consumption is and the smaller the optimal cutter spacing is. Under extremely hard rock condition, the specific energy consumption of the 12-mm-blade-width cutters is 37.9% lower than that of conventional cutters. (3) With a certain gross thrust of a single cutter, the rock-breaking quantity of a single 12-mm-blade-width cutter is much larger than that of the 19-mm-blade-width cutter, regardless of the types of rock. Under extremely hard rock conditions, the S/P of the 12-mm-blade-width cutter with the highest rock-breaking efficiency is approximately 10–12. [ABSTRACT FROM AUTHOR]

In recent years, in order to solve the problem of limited energy of sensor nodes, energy-harvesting wireless sensor network has become a research hotspot. Aiming at the shortcomings such as limited capacity, charging/discharging loss, and energy leakage of batteries in sensor nodes, a harvest-use-store structure with nonideal batteries is proposed. A mathematical model is established by combining three aspects of routing, link scheduling and energy allocation. The shortest frame is obtained by solving the mix integer linear equation. The simulation results show that, the frame length is decreased by up to 48+ with the charging/discharging efficiency increased from 0.6 to 0.9. When the energy leakage ratio is reduced from 0.04 to 0.01, the frame length is reduced by up to 33%. Expanding battery capacity has little effect on the frame length. In contrast to harvest-storage-use structure, the frame length of harvest-use-store structure is decreased by up to 11%. It is verified that the proposed method improves the network throughput greatly by improving the charging/discharging efficiency and reducing the energy leakage rate. [ABSTRACT FROM AUTHOR]

Short-chain fluorocarbon surfactants have been widely adopted as substitutes for long-chain fluorocarbon surfactants and hydrocarbon surfactants due to their biodegradability and excellent surface properties. In particular, fluorocarbon surfactants such as short-chain perfluoropolyethers have become a research hotspot in recent years. In this study, the short-chain perfluoroalkyl polyoxyethylene ether surfactant CF-310 is systematically compared with the traditional nonionic hydrocarbon surfactant alkyl polyoxyethylene ether AEO-7 in terms of its equilibrium surface tension, dynamic surface tension, wetting properties, and foam properties. The results show that CF-310 has better surface properties, better wettability on low-energy surfaces, and better foam properties than AEO-7. Structural optimization based on density functional theory (DFT) also indicates that the CF-310 fluorocarbon chain has a larger volume and a helical conformation, which are the main factors responsible for the superior surface performance, wettability, and foam performance of CF-310 compared with AEO-7. Excellent performance and biodegradability make this short-chain perfluoroalkyl polyoxyethylene ether surfactant CF-310 a more efficient alternative to AEO-7. This study tested the performance of the CF-310 system in hopes of developing its potential applications in personal and home care and foam applications. [ABSTRACT FROM AUTHOR]

Shanghai is dubbed as a role model for science and mathematics education as its fifteen-year-olds have been outperforming all in the Program for International Student Assessment (PISA) since 2009. Shanghai's achievements are attributed to its interest in adopting innovative international trends in education and equally effectively implementing these at its high and low-performing schools. One such trend in science education is based on the univariable and Control of Variable (CoV) strategies. This model is also used in constructing higher-order thinking items in science and mathematics assessments in PISA. Our first objective was to understand if students of Shanghai mastered the CoV strategies. Beyond CoV models, the emerging trend in science education promotes multivariable thinking among young adolescents. Our second objective was to understand if Shanghai has adopted this emerging trend and prepared its students on multivariable thinking. Using specially designed and previously validated assessments, we measured and compared the CoV and multivariable thinking skills of fifteen-year-olds representing one high and one low-performing school. Our results highlighted the equally exceptional performance of both schools in the CoV tasks and comparatively poor performance in the multivariable causal reasoning and prediction tasks. These findings may offer one aspect to understand Shanghai's performance in the PISA, at the same time highlight the weaknesses in its contemporary science education. [ABSTRACT FROM AUTHOR]

Exploitable or potentially exploitable deposits of critical metals, such as rare-earth (REE) and high-field-strength elements (HFSE), are commonly associated with alkaline or peralkaline igneous rocks. However, the origin, transport and concentration of these metals in peralkaline systems remains poorly understood. This study presents the results of a mineralogical and geochemical investigation of the Na-metasomatism of alkali amphiboles and clinopyroxenes from a barren peralkaline granite pluton in NE China, to assess the remobilization and redistribution of REE and HFSE during magmatic-hydrothermal evolution. Alkali amphiboles and aegirine-augites from the peralkaline granites show evolutionary trends from sodic-calcic to sodic compositions, with increasing REE and HFSE concentrations as a function of increasing Na-index [Na#, defined as molar Na/(Na + Ca) ratios]. The Na-amphiboles (i.e., arfvedsonite) and aegirine-augites can be subsequently altered, or breakdown, to form hydrothermal aegirine during late- or post-magmatic alteration. Representative compositions analyzed by insitu LA-ICPMS show that the primary aegirine-augites have high and variable REE (2194-3627 ppm) and HFSE (4194-16,862 ppm) contents, suggesting that these critical metals can be scavenged by alkali amphiboles and aegirine-augites. Compared to the primary aegirine-augites, the presentative early replacement aegirine (Aeg-I, Na# = 0.91-0.94) has notably lower REE (1484-1972) and HFSE (4351-5621) contents. In contrast, the late hydrothermal aegirine (Aeg-II, Na# = 0.92-0.96) has significantly lower REE (317-456 ppm) and HFSE (6.44-72.2 ppm) contents. Given that the increasing Na# from aegirine-augites to hydrothermal aegirines likely resulted from Na-metasomatism, a scavenging-release model can explain the remobilization of REE and HFSE in peralkaline granitic systems. The scavenging and release of REE and HFSE by Na-metasomatism provides key insights into the genesis of globally significant REE and HFSE deposits. The high Na-index of the hydrothermal aegirine might be useful as a geochemical indicator in the exploration for these critical-metals. [ABSTRACT FROM AUTHOR]

Objective: Arteriogenesis is an important mechanism that contributes to restoration of oxygen supply in chronically ischemic tissues, but remains incompletely understood due to technical limitations. This study presents a novel approach for comprehensive assessment of the remodeling pattern in a complex microvascular network containing multiple collateral microvessels. Methods: We have developed a hardware‐software integrated platform for quantitative, longitudinal, and label‐free imaging of network‐wide hemodynamic changes and arteriogenesis at the single‐vessel level. By ligating feeding arteries in the mouse ear, we induced network‐wide hemodynamic redistribution and localized arteriogenesis. The utility of this technology was demonstrated by studying the influence of obesity on microvascular arteriogenesis. Results: Simultaneously monitoring the remodeling of competing collateral arterioles revealed a new, inverse relationship between initial vascular resistance and extent of arteriogenesis. Obese mice exhibited similar remodeling responses to lean mice through the first week, including diameter increase and flow upregulation in collateral arterioles. However, these gains were subsequently lost in obese mice. Conclusions: Capable of label‐free, comprehensive, and dynamic quantification of structural and functional changes in the microvascular network in vivo, this platform opens up new opportunities to study the mechanisms of microvascular arteriogenesis, its implications in diseases, and approaches to pharmacologically rectify microvascular dysfunction. [ABSTRACT FROM AUTHOR]

Background: Parkinson's disease (PD) is the second most common neurodegenerative disease and the most common movement disorder characterized by motor impairments resulting from midbrain dopamine neuron loss. Abnormalities in small pial arteries and arterioles, which are the primary pathways of local delivery of nutrients and oxygen in brain tissue, have been reported in many neurodegenerative diseases including PD. Mutations in LRRK2 cause genetic PD and contribute to sporadic PD. The most common PD-linked mutation LRRK2 G2019S contributes 20–47% of genetic forms of PD in Caucasian populations. The human LRRK2 G2019S transgenic mouse model displays PD-like movement impairment and was used to identify novel LRRK2 inhibitors, which provides a useful model for studying microvascular abnormalities in PD. Objectives: To investigate abnormalities in arteriolar cerebral blood volume (CBVa) in various brain regions using the inflow-based vascular-space occupancy (iVASO) MRI technique in LRRK2 mouse models of PD. Methods: Anatomical and iVASO MRI scans were performed in 5 female and 7 male nontransgenic (nTg), 3 female and 4 male wild-type (WT) LRRK2, and 5 female and 7 male G2019S-LRRK2 mice of 9 months of age. CBVa was calculated and compared in the substantia nigra (SN), olfactory cortex, and prefrontal cortex. Results: Compared to nTg mice, G2019S-LRRK2 mice showed decreased CBVa in the SN, but increased CBVa in the olfactory and prefrontal cortex in both male and female groups, whereas WT-LRRK2 mice showed no change in CBVa in the SN (male and female), the olfactory (female), and prefrontal (female) cortex, but a slight increase in CBVa in the olfactory and prefrontal cortex in the male group only. Conclusions: Alterations in the blood volume of small arteries and arterioles (CBVa) were detected in the G2019S-LRRK2 mouse model of PD. The opposite changes in CBVa in the SN and the cortex indicate that PD pathology may have differential effects in different brain regions. Our results suggest the potential value of CBVa as a marker for clinical PD studies. [ABSTRACT FROM AUTHOR]

At present, most signal-to-noise ratio (SNR) estimation methods can only calculate the global and not the local SNR of seismic data. This paper proposes a calculation method of a structure-oriented-based seismic SNR attribute. The purpose is to characterize the temporal and spatial variation of the seismic data SNR. First, the local slope parameters of the seismic events are calculated using a plane wave decomposition filter. Then, the singular value decomposition method is used to calculate the local seismic data SNR, thereby obtaining it in time and space. The proposed method overcomes the insufficiency of a conventional global SNR to characterize any local seismic data features and uses the SNR as an attribute of seismic data to more accurately describe the signal-noise energy distribution characteristics of seismic data in time and space. The results of a theoretical model test and real data processing show that the SNR attribute can be used not only for seismic data quality evaluation but also for analysis and evaluation of denoising methods. [ABSTRACT FROM AUTHOR]

A novel, reactive, yellow fluorescent organosilicon dye, N -propyl-(diethoxy)methyl-silane-4-dimethylamino-naphthalimide, is designed and synthesized and is used to fabricate a covalently yellow fluorescent silicone oil by polycondensation of hydroxy-terminated polydimethylsiloxane. The chemical structure and optical properties of the N -propyl-(diethoxy)methyl-silane-4-dimethylamino-naphthalimide and covalently yellow fluorescent silicone oil are characterized by 1H nuclear magnetic resonance, 13C nuclear magnetic resonance, mass spectrometry, Fourier transform infrared, UV–Vis, and fluorescence spectra. The results indicate that the fluorescence quantum yields of N -propyl-(diethoxy)methyl-silane-4-dimethylamino-naphthalimide and covalently yellow fluorescent silicone oil are 2.61% and 3.5%, respectively. The λ max values of their dichloromethane solutions are 416 nm, and their λ ex and λ em are 430 and 509 nm, respectively. Furthermore, covalently yellow fluorescent silicone rubbers are prepared using tetraethoxysilane as a cross-linker, and some of their properties are investigated. Thermogravimetric analysis and dynamic mechanical analysis show that heat resistance and tan δ of the covalently yellow fluorescent silicone rubber are improved in comparison with silicone rubbers without N -propyl-(diethoxy)methyl-silane-4-dimethylamino-naphthalimide moieties. Solvent extraction experiments indicate that the solvent resistance of the covalently yellow fluorescent silicone rubber is much better than that of noncovalently yellow fluorescent silicone rubber. [ABSTRACT FROM AUTHOR]

Crustal delamination induced by eclogitization of orogenic roots, in addition to plate subduction, is an important process that transfers crustal materials back into the mantle. Many previous studies have demonstrated a causal link between crustal delamination and eclogitization, but actual magmatic records of the process are rarely documented. Here we present detailed studies on two distinct late Paleozoic adakite suites in the Awulale Mountains (Chinese Western Tianshan), that is, the suites with high (HN) and low (LN) Nb/Ta ratios, to constrain the regional crustal delamination. Both igneous suites have adakitic affinity and formed by partial melting of the juvenile thickened lower crust with different residual mineral assemblages in their source regions. The late Carboniferous HN adakite has superchondritic Nb/Ta (21.4–23.3) and high Dy/Yb (2.66–2.88) ratios and may have formed via rutile‐bearing, eclogite‐controlled melting of the lower crust, implying crustal thickening and eclogitization. In contrast, the Permian LN adakites have varying and lower ranges of Nb/Ta (12.9–20.0) and Dy/Yb ratios (1.35–2.53), which were probably derived from mixing of garnet‐bearing amphibolite with minor rutile‐bearing, eclogite‐controlled melts, implying crustal thinning and the end of eclogitization. The succession of these two adakite suites suggests that during the late Carboniferous to early Permian, eclogitization of the orogenic root, accompanying successive crustal delaminations, occurred in this region. Accordingly, our results imply that adakites with different geochemical features are potential tracers for the mineralogy of orogenic roots and, importantly, provide convincing evidence for eclogitization‐induced crustal delamination in orogenic belts. Key Points: Two distinct adakite groups (with super/subchondritic Nb/Ta ratios) are present in the Awulale Mountains (Chinese Western Tianshan)Adakite geochemical features are controlled by the residual mineral assemblages in the magma sourcesAdakites in orogenic belts could be used to trace eclogitization‐induced crustal delamination events [ABSTRACT FROM AUTHOR]

• Linear tungsten film deposition on silicon through LCVD is performed. • When comparing with PVD/PLD/CVD, the energy consumption of LCVD is the lowest. • Film quality is affected by laser parameters in LCVD. • Strategy for fining the uniformity is obtained and numerical validated. Nano to micro tungsten films are widely used as low resistivity electrical connections in MEMS industry. Pyrolytic laser chemical vapor deposition (LCVD) can directly fabricate thin films or microstructures with the minimum thermal damage. The optimal conditions of the tungsten film growth in LCVD are studied by combining experiments and numerical simulations. A proper region of laser powers is determined by the systematical experiments, which is in the range 40–66 W. Based on a transient numerical model, computational chemistry method within the transition state theory is employed to investigate the deposition rate in the multi-line scanning process. It is found that the energy consumption and vacuum requirement of LCVD are the lowest of all tungsten-film fabrication technologies. From the numerical results the average growth rate is controlled by the laser power and the film uniformity mainly depends on the hatch space. The results provide the guidelines of choosing optimal growing conditions and are helpful in producing high quality tungsten films using laser technique. [ABSTRACT FROM AUTHOR]

Let G be an edge-colored graph. We use e (G) and c (G) to denote the number of edges of G and the number of colors appearing on E (G) , respectively. For a vertex v ∈ V (G) , the color neighborhood of v is defined as the set of colors assigned to the edges incident to v. A subgraph of G is rainbow if all of its edges are assigned with distinct colors. The well-known Mantel's theorem states that a graph G on n vertices contains a triangle if e (G) ≥ ⌊ n 2 4 ⌋ + 1. Rademacher (1941) [8] showed that G contains at least ⌊ n 2 ⌋ triangles under the same condition. Li et al. (2014) proved a rainbow version of Mantel's theorem: An edge-colored graph G has a rainbow triangle if e (G) + c (G) ≥ n (n + 1) ∕ 2. In this paper, we first characterize all graphs G satisfying e (G) + c (G) ≥ n (n + 1) ∕ 2 − 1 but containing no rainbow triangles. Motivated by Rademacher's theorem, we then characterize all graphs G which satisfy e (G) + c (G) ≥ n (n + 1) ∕ 2 but contain only one rainbow triangle. We further obtain two results on color neighborhood conditions for the existence of rainbow short cycles. Our results improve a previous theorem due to Broersma et al. (2005). Moreover, we provide a sufficient condition in terms of color neighborhood for the existence of a specified number of vertex-disjoint rainbow cycles. [ABSTRACT FROM AUTHOR]

Abstract Given a connected graph G , the Randić index R (G) is the sum of (d (u) d (v)) − 1 ∕ 2 over all edges { u , v } of G , where d (u) and d (v) are the degrees of vertices u and v respectively. Let q (G) be the largest eigenvalue of the signless Laplacian matrix of G and n = | V (G) |. Hansen and Lucas (2010) made the following conjecture: q (G) R (G) ≤ 4 n − 4 n 4 ≤ n ≤ 12 ; n n − 1 n ≥ 13 , where the equality holds if and only if G = K n for 4 ≤ n ≤ 12 and G = S n for n ≥ 13 , respectively. Here K n is the complete graph with n vertices and S n is the star with n vertices. Deng et al. verified this conjecture for 4 ≤ n ≤ 11. In this paper, we prove the conjecture for n ≥ 12. [ABSTRACT FROM AUTHOR]

Abstract The nuclear modification of groomed jet splitting in relativistic heavy-ion collisions at RHIC and the LHC is studied based on higher twist jet energy loss formalism. Assuming coherent energy loss for two subjets, we find a non-monotonic dependence on jet energy for the nuclear modification of jet splitting function, which provides a good description of CMS and STAR groomed jet measurements. In contrast, the assumption of independent energy loss for two subjets cannot explain the observed nuclear modification pattern for groomed jet splitting. [ABSTRACT FROM AUTHOR]

Chinese mitten crab is a unique aquatic product in China. As a highly nutritious, delicious, and intriguing food, it is deeply loved by consumers. Through field visits and household interviews in Chongming District of Shanghai and Suzhou of Jiangsu Province, the author collected relevant materials and made a detailed analysis of the strengths and weaknesses, opportunities and threats of the development and application of crab culture in the development of Chinese mitten crab industry in Shanghai by using SWOT model. The results show that the development and application of crab culture in the development of Chinese mitten crab industry in Shanghai can adopt growth‐oriented, transformation and upgrading, diversification and defensive development strategies. It is expected to promote the sustainable development of Chinese mitten crab industry in Shanghai through the development and application of crab culture. [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess the cellular and molecular changes to chondrocytes in a developmental dysplasia of the hip (DDH) model and to investigate the early metabolism of chondrocytes in DDH. Neonatal Wistar rats were used for the DDH model with swaddling position. Primary cultures of chondrocytes were prepared at serial interval stages (2, 4, 6 and 8 weeks) to investigate cellular proliferation. The expression of collagen II and aggrecan mRNA was detected to assess the anabolic ability of chondrocytes. The expression of matrix metallopeptidase (MMP)-13 and ADAM metallopeptidase with thrombospondin type 1 motif 5 (ADAMTS-5) mRNA was measured to investigate the degradation of collagen II and aggrecan, respectively. Morphological changes were observed in coronal dissection samples after the removal of fixation. Primary chondrocytes at serial intervals were assessed using a Cell Counting Kit-8 assay and the results revealed that DDH chondrocytes had more proliferative activity. The expression of collagen II mRNA was upregulated at 2 weeks and was more sensitive to mechanical loading compared with aggrecan. Similar changes occurred at 6 weeks. Furthermore, MMP-13 and ADAMTS-5 mRNA expression levels were upregulated at 2 weeks. It was also demonstrated that DDH chondrocytes exhibited high proliferative activity at the early stages and degeneration later. [ABSTRACT FROM AUTHOR]

In 1962, Erdős proved that if a graph G with n vertices satisfies e ( G ) > max n − k 2 + k 2 , ⌈ ( n + 1 ) ∕ 2 ⌉ 2 + n − 1 2 2 , where the minimum degree δ ( G ) ≥ k and 1 ≤ k ≤ ( n − 1 ) ∕ 2 , then it is Hamiltonian. For n ≥ 2 k + 1 , let E n k = K k ∨ ( k K 1 + K n − 2 k ) , where “ ∨ ” is the “join” operation. One can observe e ( E n k ) = n − k 2 + k 2 and E n k is not Hamiltonian. As E n k contains induced claws for k ≥ 2 , a natural question is to characterize all 2-connected claw-free non-Hamiltonian graphs with the largest possible number of edges. We answer this question completely by proving a claw-free analog of Erdős’ theorem. Moreover, as byproducts, we establish several tight spectral conditions for a 2-connected claw-free graph to be Hamiltonian. Similar results for the traceability of connected claw-free graphs are also obtained. Our tools include Ryjáček’s claw-free closure theory and Brousek’s characterization of minimal 2-connected claw-free non-Hamiltonian graphs. [ABSTRACT FROM AUTHOR]

Abstract New generation spacecraft technology requires more and more deployable, light-weight, thin polymer films, in particular novel polyimide materials with high optical transparency, excellent foldability and superior flexibility. In this work, we develop a highly transparent, ultra-foldable, ultra-flexible and ultra-processable polyimide composite material by incorporating 5–8 wt% of ionic liquid 1-ethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide into colorless polyimide matrices. This 23-μm-thick polyimide composite film exhibits a high optical transmittance of 90.4% even at 450 nm wavelength and an incredibly low cutoff wavelength of 273 nm. It is an extremely strong and flexible material, with a tensile modulus of 844.6 MPa, a tensile strength of 48.2 MPa, a high elongation at break of 108.4%, and an extraordinary minimum bend radius of 1 μ m. It can be easily folded in half 4 times or twisted by 900° without any crack damages. Moreover, it has a low expense cost and good film processability for industrialization manufacturing. All of these superior performances render this ionic liquid/polyimide composite an ideal structural material for solar sails, solar arrays and thin-film photovoltaics, etc. Graphical abstract Image 1 Highlights • Ionic liquid/polyimide composites exhibit outstanding foldability, flexibility, processability and optical transparency. • This 23-μm-thick polyimide composite film exhibits a high optical transmittance of 90.4% even at 450 nm wavelength and an incredibly low cutoff wavelength of 273 nm. • This composite material has a super folding capability with a minimum bending radius of 1 μm, which is to our knowledge the lowest record for polymide materials. [ABSTRACT FROM AUTHOR]

• A scaled beam test was conducted to validate proposed IFCM in influence line extraction. • The proposed IFCM can extract the actual influence line of bridge structures using the dynamic response accurately. • The proposed influence line extraction method can be applied in a flexible testing condition. This paper presents a novel numerical method for accurately extracting bridge influence line (IL) from dynamic responses of general bridge structures. In this method, the IL is approximated by a multi-segment basis function, and a normalized vehicle-induced bridge response is employed as initial IL. Subsequently, an iterative fitting calculation method is proposed to eliminate fluctuation interference in the initial IL curve such that highly accurate actual bridge IL with quasi-static characteristics can be extracted. The feasibility and accuracy of the proposed IL extraction approach for bridges are validated through numerical and experimental studies. Based on which, a parametric study is conducted to identify key parameters affecting the deflection IL extraction performance. The results show that the proposed method can extract the actual bridge IL accurately and efficiently when the segment length is in the range 1/32–1/16 of the bridge span. Compared with conventional methods, the proposed method can extract the actual IL under more flexible testing conditions. Hence, the presented numerical approach is promising for IL-based bridge structure applications. [ABSTRACT FROM AUTHOR]

Motivated by the counting results for color-critical subgraphs by Mubayi (2010), we study the phenomenon behind Mubayi's theorem from a spectral perspective and start up this problem with the fundamental case of triangles. We prove tight bounds for the number of copies of triangle in a graph of order n and size m with spectral radius λ. Our results extend those of Nosal, who proved there is one triangle if λ > m , and of Rademacher, who proved there are at least ⌊ n 2 ⌋ triangles if the size is more than that of bipartite Turán graph. These results, together with two spectral inequalities due to Bollobás and Nikiforov, can be seen as a solution to the case of triangles of a problem of finding spectral versions of Mubayi's theorem. In addition, we give a short proof of the following inequality due to Bollobás and Nikiforov (2007): the number of copies of triangle t (G) ≥ λ (λ 2 − m) 3 , and characterize the extremal graphs. Some problems are proposed in the end. [ABSTRACT FROM AUTHOR]