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Schematic of red emissive carbon dots with an ultra-large Stokes shift for the multi-channel detection of pesticides.

With the development of urbanization, the urban scale of Xi'an continues to expand, and the surrounding counties and villages are administratively divided into the urban development planning of Xi'an. However, the traditional urban-rural dual economic situation has not changed, especially in the urban-rural junction area, the residents' income gap is large, the distribution of infrastructure and public facilities is obviously unbalanced, and the regional governance capacity is significantly different from the main urban area. Through the analysis of the problems in the regional governance of urban-rural integration in Xi'an, and with the help of advanced artificial intelligence technology, the measures to improve the regional governance capacity of urban-rural integration, such as changing the governance concept, enhancing the people's collaborative participation, accelerating the construction of professional personnel, and promoting the modernization of urban governance by accelerating the construction of digital intelligence technology infrastructure, are proposed to change the status quo of Xi'an's dual economy and realize real urban-rural integration, and build a modern pattern of urban governance in Xi'an metropolis.

The rapid development of traffic theory and information technology has provided diversified and large-scale traffic data resources for traffic research and urban traffic management. At the same time, these data also present many challenges, such as missing data and deviations in data collection. Many researchers have reported that inaccurate or incomplete measurements of traffic variables can be corrected based on either traditional traffic flow theory, which ignores the randomness of traffic, or are performed using machine learning methods, which emphasize data quantity, but do not make effective use of domain knowledge. This paper proposes a Traffic Factor State Network framework defined by traffic factors and their links to represent the relationships between traffic factors; this framework includes not only obvious traffic factors like volume and speed, but also hidden traffic factors such as the environmental impact factor, which is a variable used to represent complex road conditions. This variable is used to describe the influence of non-traffic flow parameters such as road condition and environmental factors, and is estimated by the EM (Expectation Maximization) algorithm based on historical data. This study used a high-order multivariate Markov model to implement the TFSN, which was then used to establish a stochastic model of speed and related factors. A large amount of historical data was used to calculate and calibrate the strength of the links between the model factors. Finally, a stochastic model of speed prediction was established. The verification results compared with actual cases demonstrate the validity and applicability of the proposed model.

Recently, the development of enzyme-like catalysts attracts increasing attention owing to their remarkable advantages over natural enzymes. Metal organic frameworks (MOFs) are ideal candidates for building biomimetic systems, because their diverse composition and structure can generate various biomimetic active centers. In this study, the postsynthetic modification was performed to create a peroxidase (POD)-mimicking catalyst through grafting ferrocene group to a Zr-based MOF material (UiO-66-NH2). The obtained UiO-66-Fc shows significant POD-like catalytic ability in the oxidation of 3,3′,5,5′-tetramethylbenzidine with the adding of hydrogen peroxide (H2O2). In addition, benefiting from the MOF moiety, UiO-66-Fc displayed enhanced catalytic activity, improved optimum condition and favorable reusability. Finally, based on the catalytic function of UiO-66-Fc, simple colorimetric methods for the quantitative detection of H2O2, glucose and uric acid were established respectively, which displayed wider linear range and lower limit of detection.

The deformation behavior of 49MnVS3 non-quenched and tempered steel was studied using isothermal compression tests at the temperature range of 750–1000 °C and the strain rate range of 0.1–50 s−1 on a Gleeble-3500 thermal mechanical simulator. The results indicated that the flow stress increases significantly with decreasing temperature and increasing strain rate. Under the whole deformation conditions, the dependence of flow stress on deformation temperature and strain rate was analyzed by hyperbolic sine equation. Besides, the hot deformation activation energy and stress exponent were calculated to be 323.56 kJ/mol and 6.99, respectively. In addition, the processing map based on dynamic material model was established, and the optimum processing condition of the 49MnVS3 non-quenched and tempered steel can be determined to be at the temperature range of 809–850 °C and strain rate of 36.6 s−1–50 s−1.

The widespread promotion and application of big data and artificial intelligence technology has brought new challenges and strong supports to traffic management. The traffic state estimation and traffic flow prediction of urban road network are important issues for intelligent transportation systems. This paper proposes a data-driven model to classify environmental impact factors through cluster analysis of large number of historical data, and then found that environmental impact factors correspond to traffic states of relevant intersections in different traffic conditions. On the basis of obtaining the corresponding traffic state, high-order multivariate Markov chain is used to predict traffic flow under different traffic states, and the accuracy of the traffic flow prediction is effectively improved. In addition, this paper also analyzes the Markov property of traffic flow time series after clustering, and use the index of Markov property to predict prediction performance. The analysis of several practical cases proves the effectiveness of the proposed method.

Glucocorticoid receptor (GR) modulates extensive biological and pathological processes including tumor progression through diverse mechanisms. The regulatory effects of dexamethasone (DEX), a synthetic glucocorticoid, as well as its interaction with GR have been recognized beyond hematologic cancers. In the present study, we investigated the anti-cancer efficacy of DEX and the correlation with GR in pancreatic cancer, a most aggressive malignancy threatening human health. The differential levels of GR expression were examined in two human pancreatic cancer cell lines, PANC-1 and SW1990, as well as in xenografts and patient tumor tissues. DEX significantly inhibited colony formation, migration, and tumor growth of PANC-1 cells expressing abundant GR. The underlying mechanisms involved suppression of nuclear factor κB (NF-κB) phosphorylation and down-regulation of epithelial-to-mesenchymal transition (EMT), interleukin 6 (IL-6) and vascular endothelial growth factor (VEGF). The anti-cancer effects of DEX were partially reversed by GR silencing or combinational administration of GR antagonist, RU486. The dose-dependent efficacy of DEX in tumor growth inhibition was also demonstrated in a GR-positive patient-derived xenograft model along with safety in mice. DEX was less potent, however, in SW1990 cells with poor GR expression. Our findings suggest that DEX effectively inhibits pancreatic tumor growth partially through GR activation. The potential correlation between GR expression and anti-cancer efficacy of DEX may have some clinical implications.

The importance of long non-coding RNAs (lncRNAs) in plant development has been established, but a systematic analysis of lncRNAs expressed during pollen development and fertilization has been elusive. We performed a time series of RNA-seq experiments at five developmental stages during pollen development and three different time points after pollination in Brassica rapa and identified 12 051 putative lncRNAs. A comprehensive view of dynamic lncRNA expression networks underpinning pollen development and fertilization was provided. B. rapa lncRNAs share many common characteristics of lncRNAs: relatively short length, low expression but specific in narrow time windows, and low evolutionary conservation. Gene modules and key lncRNAs regulating reproductive development such as exine formation were uncovered. Forty-seven cis-acting lncRNAs and 451 trans-acting lncRNAs were revealed to be highly coexpressed with their target protein-coding genes. Of particular importance are the discoveries of 14 lncRNAs that were highly coexpressed with 10 function-known pollen-associated coding genes. Fifteen lncRNAs were predicted as endogenous target mimics for 13 miRNAs, and two lncRNAs were proved to be functional target mimics for miR160 after experimental verification and shown to function in pollen development. Our study provides the systematic identification of lncRNAs during pollen development and fertilization in B. rapa and forms the foundation for future genetic, genomic, and evolutionary studies.

A series of PEG-functionalized silica nanoparticles with various molecular weight (MW 200, 400, 550, 2000, 5000 g.mol−1) have been prepared through a one-step synthesis and further used for the elaboration of temperature-responsive Pickering. The physicochemical properties of the nanoparticles were determined by TEM, TGA, DLS, surface tension and zeta potential measurements and the formed emulsions have been characterized by optical microscopy. The ability of SiO2@mPEG 550 to form temperature-responsive emulsions with oils of different nature has been explained by the hydrophilic/hydrophobic balance of the PEG/mPEG chains. The emulsions stabilized with PEG-functionalized SiO2 NPs undergo a clear temperature-triggered destabilization from room temperature to 80 °C due to the modification of the distribution of the PEG/mPEG chain at the oil-water interface.

Usually, traditional poly (ionic liquid)s are prepared to nanoparticles with high surface areas for achieving a quasi-homogeneous reaction system. In this work, a novel poly (ionic liquid) P(VB-VS)HSO4, synthesized by simply using ionic liquids immobilized on the 1-vinylimidazole-based crosslinked copolymer microsphere, was used as heterogeneous catalyst for transesterification of a novel non-edible feedstock soapberry oil to biodiesel. The structure, thermal stability and wetting property characteristics of the crosslinked copolymer microsphere particles and poly (ionic liquid) microspheres were investigated. The results indicated that ionic liquids were successfully functionalized on crosslinked copolymer microsphere, and P(VB-VS)HSO4 possessed high surface areas (100.1 m2/g), abundant meso-macropores (with diameter of ∼18.9 nm), good mechanical strength (81 N) and superior thermal stability. Benefiting from the unique structure features, these poly (ionic liquid) microspheres manifested excellent catalytic performance for transesterification of soapberry oil with methanol. A maximum fatty acid methyl esters (FAMEs) yield of 95.2% could be obtained under the response surface methodology (RSM) optimized conditions of 8.0 h reaction time, 29.1 methanol to oil molar ratio, and 8.7 wt% catalyst amount. Impressively, it was also efficient for the esterification of oleic acid, giving methyl oleate yield of 97.5%. Catalytic tests exhibited that P(VB-VS)HSO4 presented high catalytic activity and good reusability in comparison with traditional acid catalysts. The main physicochemical of the obtained soapberry biodiesel met the biodiesel standard ASTM D6751 . Therefore, this work provides a cheap and facile route to the synthesis of size-controlled poly (ionic liquid) microspheres (the diameter of the catalyst was about 500 μm) for catalyzing the production of clean biofuels.

The transesterification of palm oil and methanol catalyzed by Bronsted acidic ionic liquids was investigated. Four eco-friendly Bronsted acidic ionic liquids were prepared and their structures were characterized by NMR, FT-IR and TG–DTG. The results demonstrated that [CyN 1,1 PrSO 3 H][ p -TSA] was more efficient than the other ionic liquids and chosen as catalyst for further research. The influences of various reaction parameters on the conversion of palm oil to biodiesel were performed, and the orthogonal test was investigated to seek the optimum reaction conditions, which were illustrated as follows: methanol to oil mole ratio of 24:1, catalyst dosage of 3.0 wt% of oil, reaction temperature of 120 °C, reaction time of 150 min, and the biodiesel yield achieved 98.4%. In addition, kinetic study was established for the conversion process, with activation energy and pre-exponential factor of 122.93 kJ·mol − 1 and 1.83 × 10 15 , respectively. Meanwhile, seven-time recycling runs of ionic liquid were completed with ignorable loss of its catalyst activity. The refined biodiesel met the biodiesel standard EN 14214.

Four kinds of nanosilica-supported metallic and metatitanic acid nanocatalysts were synthesised as potential phase transfer catalysts for enhancing heavy oil recovery via a liquid-reduction method. The catalysts were carried by water and transferred into oil phase, and the catalytic performance of catalysts for the aquathermolysis reaction and viscosity reduction of the extra-heavy oil recovered at Shengli Oilfield (Dongying, China) was investigated. At a mass fraction of 1%, an aquathermolysis reaction temperature of 150°C and an aquathermolysis time of 36 h, the as-synthesised silica/zero valence iron and nickel (denoted as SiO2/Fe/Ni) catalyst was able to reduce the apparent viscosity of the two kinds of heavy oils by 79.3 and 77.6%, showing promising application in the industrial production of heavy crude oil.

Two new Bronsted acidic ionic liquids were prepared and characterized by NMR and FTIR. Their catalytic activities for the synthesis of biodiesel fuel via transesterification of tung oil with methanol were evaluated and compared to that of two imidazole-based ionic liquids for the first time. Among them, [Ps-N-Ch(Me)2][p-TSA] exhibited the highest catalytic activity and was chosen as catalyst for further research. A study on optimizing the reaction conditions was performed by orthogonal experiment based on the single factor experiment. It was found that the ranking of the significance of factors on the biodiesel yield is as follows: molar ratio of methanol to oil > reaction temperature > reaction time > catalyst dosage. The maximum biodiesel yield reaches 98.98% under the optimal reaction conditions at a molar ratio of methanol to oil of 21:1, a reaction temperature of 120 °C, a reaction time of 2 h and a catalyst dosage of 5.0 wt.%. Moreover, the reusability experiment exhibits that the catalyst can be reused five times with negligible loss of the activity. The refined biodiesel meets the biodiesel standard ASTM D6751-07, which can be used as fuel in diesel engines.

Previous studies showed that dopamine (DA) significantly reduces the frequency of cancer stem-like cells (CSC) and enhances the efficacy of sunitinib (SUN) in the treatment of breast cancer and non-small cell lung cancer (NSCLC). To overcome the shortcomings of DA in clinical practice, the purpose of this study was to investigate the efficacy as well as the underlying mechanism of an orally available, N-arylpiperazine-containing compound C2, in the treatment of pancreatic cancer when used alone or in combination with SUN. Our results showed that C2 and SUN exerted synergistic effects on inhibiting the growth of SW1990 and PANC-1 pancreatic cancer cells. C2 significantly inhibited colony formation and migration of both cells. SW1990 xenograft and patient-derived xenograft (PDX) models were utilized for pharmacodynamic investigation in vivo. C2 alone showed little inhibition effect on tumor growth but increased the anti-tumor efficacy of SUN in both xenografts. Moreover, C2 down-regulated CSC markers (CD133 and ALDH) of both cancer cells and up-regulated the expression of dopamine receptor D1 (D1DR) in tumor. Besides, the SW1990 tumor growth was dose-dependently inhibited when the cells were pretreated with C2 before implantation. C2 increased intratumoral cAMP level, and the combination with D1DR specific antagonist SCH23390 reversed the above-mentioned effects of C2 both in vitro and in vivo, indicating the activation of D1DR may be involved in the underlying mechanism of C2 action. In summary, C2 could reduce the CSC frequency and enhance the anti-cancer effect of SUN in the treatment of pancreatic cancer, demonstrating its potential in cancer therapy.

The leading causes of death in breast cancer patients are disease recurrence and metastasis. Growing evidence has suggested that metastasis possibly originates from cancer stem-like cells (CSCs). Previous studies indicated dopamine decreased CSC frequency through activating dopamine D

Aims The roles of estrogen receptors (ERs) and the efficacy of anti-estrogen (E2) therapies in pancreatic cancer stay controversial. The main objectives of this study were to investigate the potential roles of ERs in tumor progression and endocrine therapies. Main methods The ER expression status in PANC-1 and SW1990 pancreatic cancer cell lines was determined. SRB assay, colony formation assay and proliferation assay were used to investigate the responses of these cells to E2. ERα-selective agonist propylpyrazoletriol (PPT), ERβ-selective agonist diarylpropionitrile (DPN), ERα over-expressed SW1990 cells, ERα knock-out PANC-1 cells and patient-derived xenografts (PDX) were applied to investigate the potential roles of ERα in pancreatic cancer. The phosphorylation of ERα-related signaling molecules extracellular regulated protein kinases (ERK1/2) and protein kinase B (AKT) were investigated. The in vivo anti-tumor efficacy and safety of letrozole (LTZ) combined with leuprorelin acetate (LA) and gemcitabine (GEM) were also preliminarily studied. Key findings PANC-1 cells expressed much more ERα than SW1990 cells, and ERβ level was with less diversity. Accordingly, the proliferation of PANC-1 rather than SW1990 cells could be stimulated by E2, and only PANC-1 could respond to LTZ endocrine therapy in female but not male mice. The phosphorylation of ERK1/2 but not AKT was altered by over-expressed or knocking out of ERα with or without the addition of E2 and LTZ. The combination therapy of LTZ and GEM showed acceptable efficacy and safety. Significance This study showed the important roles of ERα in tumor progression and endocrine therapies of pancreatic cancer in women.

BcMF11 is a long non-coding RNA that has been identified in Brassica rapa and shown to be involved in pollen development. Here, when re-cloned the gene sequence, multiple paralogous copies of BcMF11 were identified in B. rapa (A genome). Multiple paralogous copies of BcMF11 were also found in B. nigra (B genome) and Brassica oleracea (C genome), the other two primary diploids of Brassica U triangle. While in the early diverging Brassicaceae lineage including Arabidopsis thaliana, no BcMF11 homolog was found. Phylogenetic analysis showed that the BcMF11 homologous sequences cloned from A genome or C genome could be clustered into a separate branch, respectively. However, there was no distinct cluster defined for BcMF11 homologous sequences cloned from B genome. The expression of BcMF11 in B. rapa was investigated and revealed a different result in the previous study. In addition, 12 expressed sequence tags from B. napus and B. rapa showing high similarities with BcMF11 were identified in the NCBI database, which further verified that rather than the useless repeat fragments in the genome, the BcMF11 homologous genes could transcribe. It is possible that BcMF11 and its homologous sequences may form a large gene family which might be originated in the recent ancestral lineage of Brassica.

The leading causes of death in breast cancer patients are disease recurrence and metastasis. Growing evidence has suggested that metastasis possibly originates from cancer stem-like cells (CSCs). Previous studies indicated dopamine decreased CSC frequency through activating dopamine D1 receptor pathway. Hence, this study explored the efficacy of two dopamine D1 receptor agonists in lung metastasis of breast cancer and the preliminary mechanism. The two dopamine D1 receptor agonists, fenoldopam (FEN) and l-stepholidine (l-SPD), performed well in decreasing lung metastasis in 4T1 breast cancer model. And the cGMP in the primary tumor was significantly elevated while cAMP mildly elevated in FEN and l-SPD dosing groups. CSC markers (CD44+/CD24- and ALDH+) and MMP2 in 4T1 primary tumor were repressed after dopamine D1 receptor agonist administration while E-cadherin up-regulated. FEN and l-SPD also inhibited cancer stemness and cell motility in vitro, and the inhibitory effects could be reversed by dopamine D1 receptor antagonist SCH23390. Besides, FEN impacted the white blood cell increase caused by breast cancer disease showing decreased neutrophils but increased lymphocytes. Drug safety was verified in aspects of body weight, organ index and tissue section. In conclusion, dopamine D1 receptor agonists FEN and l-SPD showed efficacy in inhibiting metastasis along with good safety in breast cancer, thus providing an alternative for anti-metastasis therapy in the future. Furthermore, this study also indicates that dopamine D1 receptor may be a possible target for metastatic breast cancer treatment and even other cancers at a late stage.

An imidazoline was prepared by solvent-free microwave-assisted organic synthesis and immobilized on porous silica particles by polymerization. The resulting material was composed of both hydrophobic alkyl ester chains and hydrophilic imidazoline rings, which gave it both hydrophilic interaction and reversed-phase characteristics. The titration curve suggests that the new material has buffering capacity and acquires increasing positive charge over the pH range 9-4, and is "zwitterionic" in the upper part of this pH range. Through investigating the effect of column temperature, the water content, pH and ion strength of mobile phase on the retention time of polar compounds in highly organic eluents, it was found that the new material could be used as a hydrophilic interaction liquid chromatography (HILIC) stationary phase which involved a complex retention process consisting of partitioning, surface adsorption and electrostatic interactions. In addition, the retention behavior of aromatic compounds in different mobile phase conditions was also studied, which showed the new material mainly exhibited a partitioning mechanism in the reversed-phase liquid chromatography (RPLC) mode. The separation of six water-soluble vitamins and five aromatic compounds were achieved by using the new material in the HILIC and RPLC modes, respectively.

In this work, a poly-l-lysine-grafted stationary phase was synthesized by polymerization of N-carboxyanhydride of l-lysine initiated by 3-aminopropylated silica. The resulting material was characterized by FT-IR spectra, elemental analysis and thermogravimetric analysis, which clearly indicated that the new phase had been prepared successfully. The retention of polar solutes depending on acetonitrile content in mobile phase exhibited “U-shaped” curves, which was an indication of hydrophilic interaction liquid chromatography (HILIC)/reversed-phase liquid chromatography (RPLC) mixed-mode retention behavior. The retention mechanisms in HILIC and RPLC modes also were investigated. Phenol compounds, aniline compounds and hydrophilic compounds were separated in RPLC or HILIC mode on the new stationary phase, respectively. This result shows that the new phase could be used for both RPLC and HILIC applications, providing greater flexibility for real sample analysis.

The GaAs MOS capacitor was fabricated with HfTiON as high- k gate dielectric and NH 3 -plasma-treated ZnON as interfacial passivation layer (IPL), and its interfacial and electrical properties are investigated compared to its counterparts with ZnON IPL but no NH 3 -plasma treatment and without ZnON IPL and no plasma treatment. Experimental results show that low interface-state density near midgap (1.17×10 12 cm -2 eV -1 ) and small gate leakage current density have been achieved for the GaAs MOS device with the stacked gate dielectric of HfTiON/ZnON plus NH 3 -plasma treatment. These improvements could be ascribed to the fact that the ZnON IPL can effectively block in-diffusion of oxygen atoms and out-diffusion of Ga and As atoms, and the NH 3 -plasma treatment can provide not only N atoms but also H atoms and NH radicals, which is greatly beneficial to removal of defective Ga/As oxides and As-As band, giving a high-quality ZnON/GaAs interface.

A novel Fe3O4@SiO2@poly-L-alanine peptide brush-magnetic microsphere (PBMMs) was synthesized from amine-functionalized Fe3O4 through the surface-initiated polymerization of N-carboxyanhydrides. Two materials with different peptide lengths were obtained from different amounts of N-carboxyanhydrides. These materials were characterized by Fourier transform infrared, transmission electron microscopy, large-angle powder X-ray diffraction, vibrating sample magnetometer and elemental analysis. Furthermore, the loading and release behavior of ibuprofen and the enrichment of bovine serum albumin on the two materials were investigated and it was shown that the PBMMs have a maximum uptake amount of ibuprofen of 40.3 mg g(-1), and an enrichment of bovine serum albumin of 20.9 mg g(-1). These materials are promising candidates for targeted drug delivery and protein enrichment.