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Relight of jet engines at high altitude is difficult due to the relatively low pressure and temperature of inlet air. The penetration of initial flame kernel affects the ignition probability in the turbine engine combustor greatly. In order to achieve successful ignition at high altitude, a deeper penetration of initial flame kernel should be generated. In this study, a Gliding Arc Plasma Jet Igniter (GAPJI) is designed to induce initial flame kernel with deeper penetration to achieve successful ignition at high altitude. The ignition performance of the GAPJI was demonstrated in a model combustor. It was found that GAPJI can generate plasma with deeper penetration up to 30.5 mm than spark igniter with 22.1 mm. The discharge power of GAPJI was positively correlated with flow rate of the carrier gas, approaching 200 W in average. Ignition experiments show that GAPJI has the advantage of extending the lean ignition limit. With GAPJI, the lean ignition limit of the combustor is 0.02 at 0 km, which is 55.6% less than that with spark igniter (0.045). The evolution of flame morphology was observed to explore the development of the flame kernel. It is shown that the advantage of a high penetration and continuous releasing energy can accelerate the ignition process and enhance combustion.

PurposeThe purpose of this study was to examine the relationship between leisure involvement (LI), conspicuous sport consumption and subjective well-being (SW) for two luxury leisure activities: golf and skiing.Design/methodology/approachThe authors collected data from Guangdong Province (golf,n = 342) and Jilin Province (skiing,n = 310) and examined the proposed model using structural equation modeling (SEM) and tested the mediating effect of conspicuous sport consumption using bootstrapping method.FindingsThe findings show that the proposed model explained the relationships among LI, conspicuous sport consumption and SW. Furthermore, the findings suggest that LI and conspicuous consumption (CC) can elevate sport participants' perception of SW, enriching leisure-class theory.Originality/valueThe authors’ findings contribute to the domain of CC in sport participant and leisure research and provide significant implications for the sport tourism marketers.

To investigate the levels of serum transforming growth factor-β 1 (TGF-β1), Matrix metalloproteinase-9 (MMP-9) and Interleukin-1 β (IL-1 β) in breast cancer (BC), and analyzing their relationship with pathological features and prognosis. Retrospective analysis of 86 subjects with BC (BC subgroup) and another 50 healthy subjects (control subgroup) during the same period were included. The clinical data were collected. In this research, in BC subgroup, The levels of serum TGF- β 1, MMP-9 and IL-1 β were significantly higher than those in control subgroup. The levels of TGF- β 1 and MMP-9 in serum of BC subjects was correlated with clinical stage, histological grade, lymph node metastasis and molecular classification, but not with age, tumor size and menopausal status. The level of serum IL-1 β was related to tumor size, clinical stage, histological grade and lymph node metastasis. Multivariate Logistic regression analysis showed that the high level of serum TGF- β1 and MMP-9 was independent risk factors for BC. High level of serum IL-1 β was not an independent risk factor for BC. The 3-year disease-free survival rate in high TGF- β1 subgroup and high MMP-9 subgroup was significantly lower than that in low TGF- β 1 subgroup and low MMP- 9 subgroup. To conclude, serum TGF- β 1, MMP-9 and IL-1β are highly expressed in BC, and the subjects with elevated serum levels of TGF- β 1 and MMP-9 suggests poor prognosis.

A cell is an organic whole containing biological macromolecules such as nucleic acid and protein. Human cells contain about 15,000 proteins, which play an important role in the development of cell life. This article aims to study the effect of phytoestrogens on the proliferation of breast cancer cells MCF-7. The estrogen-dependent MCF-7 cells described in this article are grown on average DMEM (containing calf serum 10) and connected to single cell culture. Five days before adding the test product, the cells were washed with PBS and converted into red-free phenol. High-sugar DMEM containing 5 parts of bovine embryo serum was cultured and treated with activated charcoal glucan glycosides. In the experiment, four dose groups of solvent control, estrogen control, anti-estrogens and two test substances were used for control, and the proliferation of MCF-7 cells was analyzed by integration method and flow cytometry. The experimental results in this article show that compared with the solvent control group, GS can significantly inhibit MCF-7 cell proliferation and cell DNA synthesis, and G/M can block the cell cycle and produce a similar inhibitory effect. 96mol/L zein treatment for 24 hours can significantly promote MCF-7 cell proliferation and cell DNA composition, promote cell cycle, and increase cell separation and proliferation index.

Background and Purpose: Berberine, a natural isoquinoline alkaloid, exhibits a variety of pharmacological effects but the pharmacological targets and mechanisms are remained elusive. Here, we report a novel finding that berberine inhibits acetylcholine (ACh)-induced Ca2+ oscillations which may underlie the pathogenesis of the L-arginine-induced mouse model of acute pancreatitis (AP). Experimental approach: Patch-clamp recordings and confocal Ca2+ imaging were applied in acute dissociated pancreatic acinar cells prepared from CD1 mice to examine the effects of berberine on ACh-induced Ca2+ oscillations. The L-arginine-induced acute pancreatitis mouse model was used to evaluate the protective effects of berberine against pathological changes. Key Results: Whole-cell patch-clamp recordings showed that berberine (from 0.1 to 10 µM) reduced ACh-induced Ca2+ oscillations in a concentration-dependent manner, and this inhibition was also depended on ACh concentrations. The inhibitory effect of berberine neither occurred in intracellular targets nor extracellular cholecystokinin (CCK) receptors, chloride (Cl-) channels, and store-operated Ca2+ channels. Together, the results demonstrate that berberine directly inhibits M3 muscarinic receptors, which is further confirmed by the evidence of the interaction between berberine and M3 receptors in acinar cells. In a L-arginine AP model, berberine eliminates the ACh-induced Ca2+ oscillations, the elevation of pancreatic amylase and pulmonary myeloperoxidase, and improves acinar cell pathological injury. Conclusions and Implications: We provide novel evidence that berberine inhibits M3 receptors, in turn eliminates ACh-induced Ca2+ oscillations and L-arginine-enhanced Ca2+ signaling, which underlie the protective effects of berberine on pancreatic acinar cells against pathological changes in an acute pancreatitis model.

This article examines the relationship between golf activities and tourist perceptions and intentions using data from 592 golf tourists on Hainan Island, China. The results obtained from structural equation modeling show that the attractiveness of the destination can improve the identity of the location, and both factors significantly increase the travel intentions of golf tourists (i.e. revisit intentions and word-of-mouth recommendations). The results also show that place identity has significant mediating effects between destination attractiveness and travel intentions. In addition, the results reveal that the disposable income of golf tourists has significant moderating effects on the attractiveness of the destination, the identity of the destination, and the intention to revisit. This study has some important economic implications for golf destination management. Golf course managers can improve the attractiveness of the destination and strengthen the identity of the location to enhance the behavioral intentions of golf tourists.

A new Gd-based borate crystal, Li3K9Gd3(BO3)7, has been successfully obtained via the high-temperature solution method using Li2O-K2O-B2O3 self-flux. It crystallizes in monoclinic space group P2/n (no. 10) with lattice parameters a = 11.3454(6) A, b = 9.9881(4) A, c = 11.4467(7) A, α = γ = 90 o, β = 114.782(7) o, and Z = 2. Li3K9Gd3(BO3)7 exhibits an intriguing sandwich-like three-dimensional (3D) framework constructed from [Gd-B-O]∞ layers, KOn (n = 6 and 8) polyhedra, and LiO4 tetrahedra, in which [Gd-B-O]∞ layers are built from two types of GdO8 polyhedra and triangular BO3 units. Magnetic measurements showed that Li3K9Gd3(BO3)7 exhibits a large magnetocaloric effect with -ΔSm = 39.3 J kg-1 K-1 at 2.0 K for ΔH = 7 T, which is slightly higher than that of the commercial gadolinium gallium garnet under the same conditions. The powder X-ray diffraction, infrared spectrum, and UV-vis-NIR diffuse reflectance spectrum were also performed to characterize Li3K9Gd3(BO3)7. The electronic band structures, partial density of states, and refractive indices of Li3K9Gd3(BO3)7 were investigated via the first-principle calculations.

Materials with excellent nonlinear optical properties, especially the second-harmonic-generation (SHG) ability that can double the frequency of a laser ω to 2ω, are greatly important to modern opti...

A new europium complex Eu(tta)3L1 (1a) based on 1,10-phenanthroline derivative (L1 = (2-(3,5-dimethoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), tta = 2-thenoyltrifluoroacetone) was designed and synthesized. Its structure was characterized by 1H and 13C NMR, elemental analysis, UV-vis, fluorescence spectra and single crystal X-ray diffraction. The crystal of the complex 1a belongs to monoclinic system with the space group P21/n. The europium complex 1a in the solid and in the solution displays the typical emission of Eu(III) ion centered at 612 nm as a result of the electric dipole transition (5D0 → 7F2). It exhibits high quantum yield (20.42%), long lifetime (0.29 ms) and good CIE color coordinate (0.67, 0.33) in solid. In addition, the complex shows high sensitivity and selectivity towards Al3+ and Zn2+ in methanol solution which can be attributed to the Al3+/Zn2+ cation instead of Eu3+ in the complex 1a. The LODs for Al3+ and Zn2+ were calculated to be 5.880 × 10−7 and 7.678 × 10−8 mol/L, respectively. Besides, the additions of Al3+ and Zn2+ express remarkable color changes from red to bright blue and ivory that can be clearly observed by the naked eye respectively.

An alkali-metal bismuth iodate, Na3Bi(IO3)6, was successfully obtained by the hydrothermal method for the first time and contains intriguing one-dimensional [BiI6O18] chains. High-pressure Raman spectra were carried out to investigate the structural transition of Na3Bi(IO3)6. Electronic states and anisotropic optical responses were also investigated by theoretical calculations.

An embedded multi-channel plasma igniter with C-shape and circular cavities is designed to solve the problem of secondary ignition and starting under extreme conditions, and compared with the surface multi-channel plasma igniter without cavity, the ignition process of three igniters at ground state and 12 km altitude state is recorded by high-speed camera. The results show that the ignition probability of C-shape embedded multi-channel plasma igniter is highest with the same fuel-air ratio, the ignition probability of reaching 100% is lower, and the advantage is more obvious at 12 km altitude state than at ground state. In the process of flame development, C-shape embedded multi-channel plasma igniter has the largest flame projection area, the fastest flame development speed and the shortest flame evolution time. At an altitude of 12 km, the flame stagnation stage occurs in the flame development process of the three igniters, and the ignition process of the embedded plasma igniter is less affected by the interference of air flow, which is more advantageous than the surface multi-channel plasma igniter. Flame instability occurs when the global fuel-air ratio approaches the lean ignition limit, and the flame stationary position is related to the flow field and the distribution of fuel-air ratio. The lean ignition fuel-air ratio increases exponentially as the height increases, and the advantages of C-shape embedded multi-channel plasma igniter become more and more obvious. Compared with the surface multi-channel plasma igniter, the widening percentage of lean ignition boundary of the C-shape embedded multi-channel plasma igniter can reach 21.4% at 12 km state, which is better than that of the circular embedded multi-channel plasma igniter.

Background Burnout has gained increasing attention worldwide; however, there is a lack of relevant research in China. This study investigated the prevalence and factors associated with burnout in physicians of the intensive care unit (ICU) in mainland China. Methods This cross-sectional multicenter study included critical care physicians from all provinces in mainland China (except Tibet). A self-administered survey questionnaire was conducted. It included three parts: demographic information, lifestyle and work information, and the Maslach Burnout Inventory. The levels of burnout were calculated. The factors independently associated with burnout were analyzed by logistic regression. Results Finally, 1813 intensivists participated in the survey. The participation rate was 90.7%. The prevalence of burnout and severe burnout was 82.1% (1489/1813) and 38.8% (704/1813), respectively. According to the logistic regression analysis, “difficulty in making treatment decisions” was independently associated with burnout [OR = 1.365, CI (1.060, 1.757)]. “Higher number of children” [OR = 0.714, CI (0.519, 0.981)] and higher “income satisfaction” [OR = 0.771, CI (0.619, 0.959)] were independent protective factors against severe burnout. Conclusions The burnout rate in ICU physicians in China is high. Difficult treatment decisions, the number of children, and income satisfaction are independently associated with burnout rates among ICU physicians in China. Trial registration: Burnout syndrome of the Chinese personnel working in intensive care units: a survey in China, ChiCTR-EOC-17013044, registered October 19, 2017. http://www.chictr.org.cn/showproj.aspx?proj=22329.

Graphitic carbon nitride (g-C3N4) as a metal-free candidate of photocatalyst has received worldwide attention because of its great potentials in solar light-induced degradation and hydrogen evolution, yet the industrial application is seriously hindered by the small specific surface area and rapid recombination rate of carriers. Herein, we demonstrate that porous g-C3N4 (HCl-CNU-X) can be prepared via the co-polymerization of acidified melamine and a green bubble template (urea). Transmission electron microscopy and nitrogen sorption characterization results show that the prepared HCl-CNU-X possesses an in-plane porous structure and large specific surface area, enabling the exposure of more accessible active sites. As a result, HCl-CNU-X exhibits both enhanced photocatalytic tetracycline hydrochloride degradation and higher hydrogen evolution than bulk g-C3N4. The boosted photocatalytic performance was ascribed to the formation of the porous structure, which dramatically promotes the separation of charge-carriers and facilitates the electron transfer. This work demonstrates that the acidification of nitrogen-rich precursors combined with a bubble-template can develop a new paradigm of highly porous photocatalysts for environmental remediation and water splitting.

BACKGROUND: The exact factors and mechanisms involved in the development of hematoma after breast ultrasound (US)-guided vacuum-assisted biopsy (VAB) are not clear. This study aimed to analyze the occurrence, prognosis, and risk factors of hematoma after US-guided VAB for the removal of benign breast lesions. METHODS: This was a retrospective study of consecutive female patients with breast lesions (BI-RADS 3/4a/4b and confirmed as benign by core needle biopsy) removed by percutaneous excisional biopsy by US-guided VAB at the Beijing Chaoyang Hospital from April 2016 to December 2018. Univariable analyses were conducted to identify the factors associated with hematoma (age, nodule size, laterality, nodule location, number of nodules, BI-RADS classification of ultrasound, pathology, breast shape, menstrual period, efficacy time of bandage, and hemostatic agents). Multivariable analysis was performed to identify the factors independently associated with hematoma. RESULTS: A total of 293 patients (343 breast lesions) were included. Lesion removal was successful in all cases. Hematomas ≥1 cm were found in 39 patients. Finally, 38 (97.4%) hematomas were absorbed completely within 6 months. The multivariable logistic regression analysis revealed that lesion size (P

An ultraviolet nonlinear optical (NLO) crystal La2SrB10O19 (LSB) has been firstly grown through the spontaneous crystallization using SrO-Li2O-B2O3-MoO3 flux. LSB crystallizes in noncentrosymmetric...

A gadolinium-rich borate Gd17.33(BO3)4(B2O5)2O16 was successfully grown by the high-temperature solution method using the Rb2O-B2O3 flux. The crystal crystallizes in centrosymmetric space group C2/m with lattice constants a = 18.4300(2) A, b = 3.7400(4) A, c = 14.2047(16) A, and β = 119.8550(12)°. Two different honeycomb-like [GdO] layers alternately arrange in the order ABAB forming the three-dimensional framework, in which the isolated [B2O5] and [BO3] units fill in channels of the 12-membered and 10-membered [GdO] polyhedral rings, respectively. The UV cutoff edge of Gd17.33(BO3)4(B2O5)2O16 is less than 240 nm. The maximum -ΔSm,max is 26.53 J kg-1 K-1 or 174.70 mJ cm-3 K-1 (T = 4.4 K and ΔH = 7 T) as investigated by the isothermal magnetization method.

A new non-centrosymmetric borate crystal, Rb7SrGd2(B5O10)3, was successfully grown via the spontaneous nucleation technique from the Rb2O-B2O3-SrO self-flux system. It crystallizes in the trigonal system space group R32 with lattice parameters a = b = 13.4975(5) A, c = 15.3223(8) A, α = β = 90°, γ = 120°, and Z = 3. Its three-dimensional framework is composed of isolated GdO6 and SrO6 octahedra, RbOn (n = 6 and 8) polyhedra, and [B5O10]5- clusters. Rb7SrGd2(B5O10)3 exhibits multifunctional properties, and has both moderate second harmonic generation (SHG) responses (0.5 × KDP) and paramagnetic characteristics with μeff = 8.18μB. Thermal stability, Fourier transform infrared spectroscopy, and UV-Vis-NIR diffuse reflectance spectroscopy were performed to characterize the title compound. Its electronic band structures and density of states were also investigated via first-principles calculations.

Graphitic carbon nitride (g-C