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A co-location pattern is a set of spatial features that are strongly correlated in space. However, some of these patterns could be neglected if the prevalence metrics are based solely on the clique (or star) relationship. Hence, the l-reachability co-location pattern is proposed by introducing the l-reachability clique where the members of each instance pair can be reachable to each other in a given step length l. Because the average size of l-reachability co-location patterns tends to be longer, maximal l-reachability co-location pattern mining is researched in this paper. First, some sparsification strategies are introduced to shorten star neighborhood lists of instances in an updated graph called the l-reachability neighbor relationship graph, and then, they are grouped by their corresponding patterns. Second, candidate maximal l-reachability co-location patterns are iteratively detected in a size-independent way on bi-graphs that contain group keys and their intersection sets. Third, the prevalence of each candidate maximal l-reachability co-location pattern is checked in a binary search way with a natural l-reachability clique called the ⌊l/2⌋-reachability neighborhood list. Finally, the effectiveness and efficiency of our model and algorithms are analyzed by extensive comparison experiments on synthetic and real-world spatial data sets.

This paper presents a novel hybrid in-situ additive manufacturing (AM) method —Laser Shock Forging (LSF), which combines laser shock peening (LSP) with laser melting deposition (LMD). Based on the classical Bar-frame model and inherent strain theory, the mechanisms of the effects of pretreatment and post-treatment on AM process has been firstly elaborated. Towards controlling tensile residual stress (TRS) in the as-built (AB) state of AM parts which has a detrimental effect on their fatigue life, we then developed LSF to introduce tensile inherent strains in LMD built parts in an in-situ manner, which will convert TRS to compressive residual stress (CRS). The laser beam used for shock peening can be adjusted to move synchronously with the laser beam used for metal deposition at a certain distance, ensuring the laser shock peening to act on the region where the material temperature cools down to the forging temperature range. Then experimental works have been conducted on 316L stainless steel, residual stress distributions of the AB, LSP and LSF treated specimens were compared, results show that LSF increases both the magnitude and depth of CRS compared with conventional LSP treatment, thus providing a promising application in enhancing fatigue life in AM process.

The improvement of methyl lactate yield was achieved by constructing water-tolerant Lewis acid sites, which were generated by reducing hydroxyl groups and increasing coordinatively unsaturated sites.

Abstract: Colloidal crystal (CC) fiber has unique light manipulation characteristics, fiber flexibility, and the potential to be used in the textile industry as an alternative to chemical dyes. Introducing polyamide 66 (PA66) into CC fiber can effectively improve the performance of fibers. In this study, polyamide 66 (PA66) CC fibers with various morphologies were fabricated by electrospinning using high-tensile PA66 and P(St-MMA-AA) latex particles as raw materials, such as close-packed, inlaid, noodle-like, spindle knots, bamboo-like, semi-enclosed, hat-like, etc. The formation mechanism of various fibers was analyzed based on the phase separation and assembly interaction. The prepared PA66 CC fiber film was reported to have unique structural color and enhanced mechanical properties, which can be used as a substrate for drawing various patterns. This work will provide a novel idea for the fabrication of functional CC fiber, which is helpful for the potential application in the textile industry.

Neuroblastoma (NB) is one of the most common extracranial tumors with limited therapeutic options. Retinoic acid (RA) has been identified to play anticancer role against NB cells by inducing the differentiation and apoptosis of immature neuroblasts. However, silencing HoxC9 promoter by EZH2-induced H3K27me3 hypermethylation can lead to RA resistance. Previous studies have suggested that arsenic trioxide (ATO), an inhibitor of DNA methylation, could downregulate the expression of EZH2 in breast cancer cells.In our study, we attempted to obtain some insight into the mechanisms of differentiation of RA-resistant NB cells by detecting the expressions of HoxC9 and EZH2 in NB cells treated with ATO, so as to provide a basis for the subsequent treatment of RA-resistant NB by ATO.Two NB cell lines, SK-N-AS (retinoic acid-resistant neuroblastoma cells) and SK-N-SH (retinoic acid-sensitive neuroblastoma cells), were used in our experiments. Cell proliferation and apoptosis were respectively determined with Cell Counting Kit-8 (CCK-8) assay kit and Annexin V staining. The inverted phase contrast microscope was used to observe cell growth and measure the total length of nerve synapses. We employed label-free quantitative proteomic analysis to profile ATO-dependent changes in the proteome of NB cells. Western blot was used to detect the expressions of HoxC9, HoxD8 and EZH2.Arsenic trioxide inhibited the cell proliferation and increased apoptosis and total length of synapses in two NB cell lines. The expressions of HoxC9 and HoxD8 were upregulated, while the expression of EZH2 was downregulated in the SK-N-AS cell line. No significant changes in the 3 proteins mentioned above were observed in the SK-N-SH cell line after ATO treatment.Arsenic trioxide may reactivate the expression of HoxC9 by downregulating EZH2, which leads to restoring RA sensitivity and promoting the differentiation and apoptosis of RA-resistant NB cells.

SUMMARY The integrating technique of multigeophysical data sets has been treated as a feasible way to improve the imaging resolution of the subsurface structure. Based on the limited memory quasi-Newton approach, we obtain the electrical and velocity structure through the individual inversions of magnetotelluric (MT) and ambient noise dispersion data, and propose an alternating joint inversion strategy for integrating the MT and dispersion data with the cross-gradient structure constraints. A synthetic model has been applied to test the reliability and effectiveness of the joint inversion scheme. Some significant improvements have been achieved and shown in the joint inversion maps: the resolution of deep electric features is improved, especially that of the structure beneath the conductive layer; a finer velocity model is obtained than that of the ambient noise tomography. Based on the complementary advantages of the two geophysical methods, resistivity and velocity models with higher geometrical resemblance can be obtained. We also apply the method to the field data from the Tanlu fault zone, Eastern China. Structure similarities have been observed in the main features of the joint inversion models, which further validates the effectiveness and practicality of the proposed joint inversion strategy.

La1-xSrxMnO3 is a well-known oxygen electrode for reversible solid oxide cells (RSOCs). However, its poor ionic conductivity limits its performance in redox reaction. In this study, we selected Sm0.5Sr0.5CoO3-δ (SSC) as catalyst and Sm0.2Ce0.8O1.9 (SDC) as ionic conductor and sintering inhibitor to co-modify the La0.65Sr0.35MnO3 (LSM) oxygen electrode through an alternate infiltration method. The infiltration sequence of SSC and SDC showed an influence on the morphology and performance of LSM oxygen electrode, and the influence was gradually weakened with the increasing infiltration time. The polarization resistance of the alternately infiltrated LSM-SSC/SDC electrode was 0.08 Ω cm2 at 800 °C in air, which was 3.36% of the LSM electrode (2.38 Ω cm2). The Ni-YSZ/YSZ/LSM-SSC/SDC single cell attained a maximum power density of 1205 mW cm−2 in SOFC mode at 800 °C, which was 8.73 times more than the cell with LSM electrode. The current density achieved 1620 mA .cm−2 under 1.5 V at 800 °C in SOEC mode and the H2 generation rate was 3.47 times of the LSM oxygen electrode.

Ordered “nest-like” hierarchical ZSM-48 (NSH-ZSM-48) hollow spheres stacked by uniform nanorods with superior accessibility were synthesized utilizing a novel bolaform s-triazine based surfactant, and the proper formation mechanism was proposed.

The existing literature lacks the classification of product quality upgrading levels and ignores the effect of product quality upgrading at different hierarchical levels on firms' export performance. Based on this, this paper takes Chinese manufacturing exporters as the research subjects, using panel fixed effects and instrumental variables methods, and empirically examines the effect of product quality upgrading (and product quality upgrading at different levels) on firms' export performance using the 2000-2013 China Import and Export Customs Database, the China Industrial Enterprises Database, and a self-curated product quality upgrading database. The results of the research show that the number of Chinese manufacturing exporters that have upgraded their product quality is increasing. The mean and the level of product quality upgrading are both constantly elevating. Product quality upgrading has a significant positive effect on export performance, and the positive effect of product quality upgrading on export performance is greater for high-level product quality upgrading than for low and medium-level product quality upgrading. The positive effect of product quality upgrading on export performance is greater for state-owned enterprises, small enterprises, and enterprises in central and western regions. The empirical results help to refine the understanding of the export growth effect brought by product quality upgrading and provide micro evidence for China's "Great Power of Quality" strategy.

This nonrandomized, multicenter cohort, open-label clinical trial evaluated the efficacy and safety of combined chemotherapy with arsenic trioxide (ATO) in children with stage 4/M neuroblastoma (NB). We enrolled patients who were newly diagnosed with NB and assessed as stage 4/M and received either traditional chemotherapy or ATO combined with chemotherapy according to their own wishes. Twenty-two patients were enrolled in the trial group (ATO combined with chemotherapy), and 13 patients were enrolled in the control group (traditional chemotherapy). Objective response rate (ORR) at 4 weeks after completing induction chemotherapy was defined as the main outcome, and adverse events were monitored and graded in the meantime. Data cutoff date was December 31, 2019. Finally, we found that patients who received ATO combined with chemotherapy had a significantly higher response rate than those who were treated with traditional chemotherapy (ORR: 86.36% vs. 46.16%,p=0.020). Reversible cardiotoxicity was just observed in three patients who were treated with ATO, and no other differential adverse events were observed between the two groups. ATO combined with chemotherapy can significantly improve end-induction response in high-risk NB, and our novel regimen is well tolerated in pediatric patients. These results highlight the superiority of chemotherapy with ATO, which creates new opportunity for prolonging survival. In addition, this treatment protocol minimizes therapeutic costs compared with anti-GD2 therapy, MIBG, and proton therapy and can decrease the burden to families and society. However, we also need to evaluate more cases to consolidate our conclusion.

Summary Designing superwettable surfaces for enhancing the reaction efficiencies has been being attracted attention. Herein, we report a distinct strategy that hydrophobic bis((trifluoromethyl)sulfonyl)imide (NTf2)-based ionic liquids can endow hydrophobic carbon with superhydrophilicity and superoleophilicity simultaneously via a one-step method in a large scale. Wettability mechanisms demonstrate that superhydrophilicity of the as-prepared carbon is mainly attributed to pyridinic N-oxide from the thermolysis of the NTf2 anion, whereas superoleophilicity of the carbon is provided by the elements C and F. Furthermore, superamphiphilic carbon can greatly eliminate the diffusion resistance thereby enhancing the reaction efficiencies in liquid-liquid systems by rapid enrichment of reactants around catalysts and increasing phase interfacial areas. This work provides a general route to construct superamphiphilic carbon that can greatly enhance the reaction efficiencies.

Soft template designing is the most promised strategy for synthesis of zeolites nanosheets. So far, MFI nanosheets directed by soft templates (containing long chain alkyl groups or aromatic groups as hydrophobic component), can be found frequently. However, the MFI nanosheets synthesized by soft template with aromatic heterocycle groups (e.g. s-triazine groups) are rare. Herein, nanosheets stacked hierarchical MFI zeolite (NSHM) has been synthesized utilizing a triply branched s-triazine based surfactant as a bifunctional organic structure-directing agent. On the basis of geometrical match relationship, a formation model has been proposed. Synthesized NSHM was endowed with abundant mesopores stacked by nanosheets and exhibited a high surface area (430 m 2 ‬·g -1 ). The 1 wt% Pd/NSHM attained a significant increase in cyclohexanol/cyclohexanone mixture yield (from 66% to 85%) in oxidation of cyclohexane compared with Silicalite-1 and SBA-15 as supports.

In this work, using the phase-field model, we demonstrated vortex structure can be generated in a lead-free BaTiO3/SrTiO3 superlattice structure. The labyrinth pattern (maze-like) domain structure was observed in a fully relaxed BaTiO3/SrTiO3 superlattice structure. Topological bubble-like rosette structures were found at an out-of-plane field, and polar skyrmions were obtained after the electric field was removed. In a designed fully relaxed nanowire of width ∼8 nm, near-perfect periodical clockwise-counterclockwise ferroelectric vortex pairs were generated due to the interfacial constraints. The simulated topological structures are potentially relevant to the application of high-density ferroelectrics memory devices.

On August 8, 2017, a magnitude 7.0 earthquake occurred in Jiuzhaigou County, Sichuan Province, China. The deep seismogenic environment and potential seismic risk in the eastern margin of Tibetan Plateau have once again attracted the close attention of seismologists and scholars at home and abroad. The post-earthquake scientific investigation could not identify noticeable surface rupture zones in the affected area; the complex tectonic background and the reason(s) for the frequent seismicity in the Jiuzhaigou earthquake region are unclear. In order to reveal the characteristics of the deep medium and the seismogenic environment of the M7.0 Jiuzhaigou earthquake region, and to interpret the tectonic background and genesis of the seismicity comprehensively, in this paper, we have reviewed all available observation data recorded by the regional digital seismic networks and large-scale, dense mobile seismic array (China Array) for the northern section of the North–South Seismic Belt around Jiuzhaigou earthquake region. Using double-difference seismic tomography method to invert the three-dimensional P-wave velocity structure characteristics of the upper crust around the Jiuzhaigou earthquake region, we have analyzed and discussed such scientific questions as the relationship between the velocity structure characteristics and seismicity in the Jiuzhaigou earthquake region, its deep tectonic environment, and the ongoing seismic risk in this region. We report that: the P-wave velocity structure of the upper crust around the Jiuzhaigoug earthquake region exhibits obvious lateral inhomogeneity; the distribution characteristics of the shallow P-wave velocity structure are closely related to surface geological structure and formation lithology; the M7.0 Jiuzhaigou earthquake sequence is closely related to the velocity structure of the upper crust; the mainshock of the M7.0 earthquake occurred in the upper crust; the inhomogeneous variation of the velocity structure of the Jiuzhaigou earthquake area and its surrounding medium appears to be the deep structural factor controlling the spatial distribution of the mainshock and its sequence. The 3D P-wave velocity structure also suggests that the crustal low-velocity layer of northeastern SGB (Songpan–Garze Block) stretches into MSM (Minshan Mountain), and migrates to the northeast, but the tendency to emerge as a shallow layer is impeded by the high-velocity zone of Nanping Nappe tectonics and the Bikou Block. Our results reveal an uneven distribution of high- and low-velocity structures around the Tazang segment of the East Kunlun fault zone. Given that the rupture caused by the Jiuzhaigou earthquake has enhanced the stress fields at both ends of the seismogenic fault, it is very important to stay vigilant to possible seismic hazards in the large seismic gap at the Maqu–Maqen segment of the East Kunlun fault zone.

Monitoring and post-processing of organic solvents are important for environmental protection. Challenges remain in the development of a universal material which can detect any solvent with a large stopband shift and show excellent stability. Herein, we demonstrate a poly 3,4-ethylenedioxythiophene inverse opal (PEDOT-IO) with a large stopband shift toward various solvents based on the insolubility/superoleophilicity properties. The PEDOT-IO film was fabricated by the potentiostatic polymerization of 3,4-ethylene dioxythiophene using a three-electrode system, infiltrating the interstices of the photonic crystal template with PEDOT and subsequently removing the template. The surface of the PEDOT-IO film presented a composite structure: interconnected pores and hollow shells. When the solvent was introduced into the voids of PEDOT-IO film, the effective refractive index (n) of the whole sample increased due to the replacement of air with the solvent, and the pores and hollow shells showed different degrees of swelling. The synergistic effect of increased n and volume expansion contributed to a large redshift of the stopband of the PEDOT-IO film. PEDOT-IO film exhibited excellent resistance to various solvents and high/low temperature. This work further enriches the application of conductive polymers in solvent-responsive PC sensors and provides a novel means of creating PC-based optical materials and devices., Multi-solvent monitoring was achieved based on the insolubility/superoleophilicity properties of PEDOT-IO. The synergistic effect of increased effective refractive index and volume expansion contributed to a large redshift of the stopband.

Although orthostatic hypotension (OH) and orthostatic hypertension (OHT) can independently predict cardiovascular events, the underlying mechanisms remain controversial. Our study aimed to examine the relationships between orthostatic blood pressure (BP) changes and arterial stiffness.In this cross-sectional analysis, 1820 participants were divided into three groups according to BP changes within 3 min of orthostatism: the OH group had a decrease of20 mmHg in SBP or10 mmHg in DBP, the OHT group had an increase of ≥20 mmHg in SBP, and the orthostatic normotensive (ONT) group had normal changes. Arterial stiffness was assessed by measuring the carotid-femoral pulse wave velocity (cfPWV).OH and OHT were observed in 257 (14.1%) and 62 (3.4%) participants, respectively. Subjects in the OH group were significantly older, were more likely to have hypertension and diabetes, and had higher cfPWV than those in the ONT group ( P 0.05); however, no differences were found between the ONT and OHT groups. Stepwise multiple regression analysis of the subgroups stratified by hypertension and diabetes revealed that age was related to increased cfPWV in all stratifications, and the change in SBP was significantly positively correlated with cfPWV in hypertensive subjects; however, this association was not observed in nonhypertensive subjects.We found that arterial stiffness was closely related to OH but not to OHT. In addition to expanding current knowledge of the relationship between orthostatic BP changes and arterial stiffness, our study underlines the importance of age, SBP changes, and hypertension in evaluating arterial stiffness.

A single-chamber solid oxide fuel cell micro-stack with a linear array arrangement has been particularly investigated in methane-oxygen-argon mixture. The stack with four cells connected in series exhibited an open-circuit voltage of 3.7 V and a maximum power output of 353 mW (total active area: 2 cm2) at 700 °C. The performance of the cells was gradually reduced along with the gas flow direction at Ar flow rate of 140 sccm and the performance difference between the cells was decreased with the increasing gas flow rate. Results showed that a CH4/O2 ratio of 1 was the most favorable ratio for the downstream cells. The power output of the linear stack at Ar flow rate of 140 sccm was 50% higher than that of the previous stack with equal inlet gas for each single cell, which proved an advantage for the linear array arrangement at low gas flow rate not only for fuel economy but also for a better stack performance.

In wireless acoustic sensor networks (WASNs), usually each sensor node has an individual clock source and captures the acoustic sources asynchronously. Due to the independent oscillators, a sampling rate offset (SRO) is inevitable between different devices. The SRO has an adverse effect on the performance of algorithms. In this work, we propose a method for estimating the SROs and time difference of arrivals (TDOAs) jointly. The SROs and TDOAs are firstly approximated by a linear-phase difference model in the short-time Fourier transform domain, and then estimated by a least-squares estimator. Further, we analyze the Cramer-Rao lower bound (CRLB) for the considered estimator. Simulation results show that for both SRO estimation and source localization problems, the proposed method achieves an improvement for asynchronous WASNs.

Background Owing to its combined effects, the co-delivery of different therapeutics is a promising option for the treatment of cancer. In the present study, tumor-targeting poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) nanoparticles were developed for the transportation of two molecules, namely chemotherapeutic drug 5-fluorouracil (5Fu) and radionuclide iodine-131 (131I), in a single platform. Methods The obtained nanoparticles (Cetuximab [Cet]-PEG-PLA-5Fu-131I) were spherical (diameter approximately 110 nm) and pH-sensitive. The targeting effect of nanoparticles via Cet was confirmed in colorectal cancer cells using a fluorescent assay. The combined effects of Cet-PEG-PLA-5Fu-131I on cell viability and apoptosis were evaluated in colorectal cancer cells by Cell Counting Kit-8 and flow cytometry assays. Results Blank nanoparticles (Cet-PEG-PLA) showed good biocompatibility, and Cet-PEG-PLA-5Fu-131I nanoparticles were the most effective in terms of inhibition of cell viability and induction of apoptosis compared with monotherapy using Cet-PEG-PLA-5Fu or Cet-PEG-PLA-131I. In the xenograft mouse model, compared with using Cet-PEG-PLA-5Fu or Cet-PEG-PLA-131I alone, Cet-PEG-PLA-5Fu-131I nanoparticles exhibited prolonged circulation in the blood and accumulation in the tumor, thus resulting in enhanced antitumor efficacy. Additionally, combined radio-chemotherapy with Cet-PEG-PLA-5Fu-131I nanoparticles was associated with smaller tumor sizes than monotherapy, revealing the superior antitumor effects of Cet-PEG-PLA-5Fu-131I nanoparticles. These effects were further evidenced by histological and immunohistochemical analyses. Conclusion The multifunctional Cet-PEG-PLA-5Fu-131I nanoparticles are promising candidates for the co-delivery of 5Fu-mediated chemotherapy and 131I-mediated radiotherapy.

The aim of this study was to describe ultrasound (US) and contrast-enhanced ultrasound (CEUS) findings immediately and 1 d after percutaneous irreversible electroporation (IRE) of hepatic malignant tumors. Immediately after IRE, the ablation zone was shown to be a gradually expanding hypo-echoic area around the electrodes. The microcirculation of the ablation zone was markedly reduced on CEUS (before vs. immediately after, p0.001), and the macrocirculation within the ablation zone was preserved. At 1 d after IRE, the ablation zones lost their hypo-echogenicity to become iso-echoic or hyper-echoic (before vs. 1 d after, p = 0.004; immediately after vs. 1 d after, p = 0.002). At this time, further elimination of microcirculation was confirmed on CEUS (before vs. 1 d after, p0.001; immediately after vs. 1 d after, p = 0.003). The size of the ablation zone, which measured by US, was strongly correlated with that measured by CEUS (length: r: = 0.929, width: r = 0.940, p0.001), was significantly enlarged immediately after IRE and shrunk 1 d after IRE.