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The biodegradation of polycyclic aromatic hydrocarbons (PAHs) by micro-organisms in the environment is often inhibited by coexisting metal ions. The aim of this work is to study a bacterial consortium for enhancing phenanthrene biodegradation under the inhibition effect of the rare earth (RE) ions Ce3+ and Y3+. This bacterial consortium was composed of two bacteria, namely, the RE-adsorbing Bacillus subtilis MSP117 and the phenanthrene-degrading Moraxella osloensis CFP312. Ce3+ and Y3+ at the concentration of 1·15 mmol l−1 inhibited CFP312 from degrading phenanthrene but not glucose. Using glucose as a co-substrate could promote the proliferation of CFP312 but decreased phenanthrene degradation. Adsorption experiments and electron microscopy imaging showed that CFP312 had no RE ions adsorption capacity for RE ions and that RE elements could not be observed on its cell surfaces. MSP117 could adsorb 0·14 and 0·12 mmol g−1 wet cells of Ce3+ and Y3+ in aqueous solution, respectively, thus demonstrating considerable adsorption capacity. The MSP117 cell surface immobilized part of the free RE ions and reduced their bioaccessibility, thereby alleviating their biotoxic effect on phenanthrene degradation by CFP312. In liquid and slurry systems, glucose, which was used as the co-substrate of the bacterial consortium, must be kept at a low level to avoid the catabolism repression of phenanthrene degradation by CFP312.

Macrophages play an important part in the pathogenesis of osteoarthritis (OA). Our objective was to determine the effects of α-defensin-1 on macrophage polarization and consequently OA.OA synovial tissue and synovial fluid were assessed for the presence of M1 (CD68The quantity of M1 exceeded M2 polarized macrophages in human OA synovial tissue (mean difference 26.1% [13.6-38.6%], P 0.001) and fluid (mean difference 10.5% [5.0-16.1%], P = 0.003). M1 to M2 polarization in vitro was most effectively promoted with 10 ng/mL α-defensin-1. Compared with untreated macrophages, the α-defensin-1 polarized macrophages modified co-cultured OA chondrocytes from a pro-catabolic state to a pro-anabolic (regenerative-like) state based on expression of COL2A1, ACN, MMP3, MMP13 and ADAMTS5. Intra-articular α-defensin-1 decreased severity of cartilage damage and synovitis in the MLI rat model. RNAseq analyses suggested insulin and Toll-like receptor signaling pathways in the chondroprotective α-defensin-1 mechanism of action.α-defensin-1 promotes M1 to M2 macrophage polarization in vitro, has beneficial effects on chondrocytes indirectly via M2 macrophage polarization, and attenuates the severity of OA in vivo, suggesting it might be a candidate treatment for OA.

Let $$n$$ be a positive integer and $$\mathcal{R}$$ be a $$2$$ and $$n!$$ -torsion free commutative ring with unity. Let $$X$$ be a locally finite pre-ordered set. If any two directed edges in each connected component of the complete Hasse diagram $$(X,\mathfrak{D})$$ are contained in one cycle, then every $$n$$ -commuting map on the incidence algebra $$I(X,\mathcal{R})$$ is proper.

This paper proposes an alternating elliptical impingement chamber in the leading edge of a gas turbine to restrain the cross flow and enhance the heat transfer, and investigates the detailed flow and heat transfer characteristics. The chamber consists of straight sections and transition sections. Numerical simulations are performed by solving the three-dimensional (3D) steady Reynolds-Averaged Navier–Stokes (RANS) equations with the Shear Stress Transport (SST) k– $\omega$ turbulence model. The influences of alternating the cross section on the impingement flow and heat transfer of the chamber are studied by comparison with a smooth semi-elliptical impingement chamber at a cross-flow Velocity Ratio (VR) of 0.2 and Temperature Ratio (TR) of 1.00 in the primary study. Then, the effects of the cross-flow VR and TR are further investigated. The results reveal that, in the semi-elliptical impingement chamber, the impingement jet is deflected by the cross flow and the heat transfer performance is degraded. However, in the alternating elliptical chamber, the cross flow is transformed to a pair of longitudinal vortices, and the flow direction at the centre of the cross section is parallel to the impingement jet, thus improving the jet penetration ability and enhancing the impingement heat transfer. In addition, the heat transfer in the semi-elliptical chamber degrades rapidly away from the stagnation region, while the longitudinal vortices enhance the heat transfer further, making the heat transfer coefficient distribution more uniform. The Nusselt number decreases with increase of VR and TR for both the semi-elliptical chamber and the alternating elliptical chamber. The alternating elliptical chamber enhances the heat transfer and moves the stagnation point up for all VR and TR, and the heat transfer enhancement is more obvious at high cross-flow velocity ratio.

The epidermal growth factor receptor (EGFR) signaling is aberrantly overexpressed in many solid malignancies, making it an important target for anti-cancer biologic agents. Among them, epidermal growth factor receptor inhibitors (EGFRIs), which have been widely used in clinical practice, include anti-EGFR monoclonal antibodies and tyrosine kinase inhibitors. A proportion of patients treated with EGFRIs develop specific, dose-dependent skin toxicity such as papulopustular rash, paronychia, xerosis and itch. These side effects can cause physical and psychosocial discomfort that may result in dose reduction, discontinuance, or replacement of the current EGFRIs treatment. Correct diagnosis and treatment of these skin and mucosal adverse effects associated with EGFRIs is of great significance for the tertiary prevention of malignant tumors. A review on EGFRI-related mucocutaneous adverse reactions is presented here, focusing on the pathogenesis, the various clinical manifestations, the strategies for prevention and treatment of these conditions.表皮生长因子受体（EGFR）在多种恶性肿瘤中存在过表达，使其成为抗肿瘤生物制剂治疗的重要靶点。针对该靶点的表皮生长因子受体抑制剂（EGFRIs）临床上应用较广泛，包括抗EGFR单克隆抗体和酪氨酸激酶抑制剂。接受EGFRIs治疗的部分患者可出现特征性的剂量依赖性皮肤黏膜不良反应，常见类型包括痤疮样皮疹、甲沟炎、皮肤干燥和瘙痒等。这些副作用会导致患者身体、心理的不适，致使抗肿瘤靶向药物剂量调整、方案更换甚至治疗中断。正确识别和处置EGFRIs相关皮肤黏膜不良反应对于肿瘤的三级预防具有重要意义。本文就EGFRI相关皮肤黏膜不良反应的发病机制、各种临床表现及其防治策略进行阐述。.

Affected by the COVID-19 pandemic, teaching tasks have gradually shifted from offline to online, which expanded online education resources unprecedentedly. “Concept” is a professional vocabulary in the curriculum. Exploring the prerequisite relations among concepts is of great significance to educational planning. This research extracts concepts from online course introduction and proposes a mixed method for extracting concept prerequisite relations. Experiments on public data set show that this method outperforms existing ones. Tests were also carried out on the datasets of eleven schools, which proves that this model has good scalability. © 2021 Knowledge Systems Institute Graduate School. All rights reserved.

We projected incident surface solar radiation (SSR) over China in the middle (2040–2059) and end (2080–2099) of the 21st century in the Representative Concentration Pathway (RCP) 8.5 scenario using a multi-model ensemble derived from the weighted average of seven global climate models (GCMs). The multi-model ensemble captured the contemporary (1979–2005) spatial and temporal characteristics of SSR and reproduced the long-term temporal evolution of the mean annual SSR in China. However, it tended to overestimate values compared to observations due to the absence of aerosol effects in the simulations. The future changes in SSR showed increases over eastern and southern China, and decreases over the Tibetan Plateau (TP) and northwest China relative to the present day. At the end of the 21st century, there were SSR increases of 9–21 W m−2 over northwest, central, and south China, and decreases of 18–30 W m−2 over the TP in June–July–August (JJA). In northeast China, SSR showed seasonal variation with increases in JJA and decreases in December–January–February. The time series of annual SSR had a decreased linear trend for the TP, and a slightly increased trend for China during 2006–2099. The results of our study suggest that solar energy resources will likely decrease in the TP under future climate change scenarios.

Limited by scarce observations, the sources and transport of aerosols over Central Asia are relatively unclear. In this study, using Terra and Aqua satellite images, Moderate Resolution Imaging Spectroradiometer (MODIS) data, Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite observations and meteorological reanalyze data, the distribution, source and transport of aerosols over Central Asia are investigated. We find that there are 227 aerosol events occurred in Central Asia during 2000–2017 and the aerosols which can be transported from outside to Central Asia are dominated by dust and smoke (organic carbon and black carbon) particles. Statistical analyses show that the contribution of the sources outside of Central Asia (76 times) to all aerosol events (122 times) is greater than that of local emissions in Central Asia (46 times) in the spring and summer during 2000–2017. The smoke events (39 times), sourcing from Russia and Europe with strong northwest wind, account for 51.3% of total aerosol events contributed by sources outside of Central Asia. Additionally, the dust events (37 times), which mainly source from the northern Arabia Peninsula and North Africa with strong southwest wind, account for 48.7% of the total aerosol events contributed by the sources outside of Central Asia. On the contrary, the contribution of local emissions in Central Asia (90 times) to all aerosol events (105 times) is greater than that of outside sources (15 times) in the autumn and winter. Result of clustering analyses for all 157 aerosol events during 2005–2017 is in agreement with the conclusion of statistical analyses based on observations. This study can provide some evidence to understand the aerosol properties over the Central Asia.

This paper aims to investigate the influences of steel diagonal braces (SDB) on the deformation performance and seismic behavior of steel truss-RC tubular column hybrid structures. Firstly,...

In order to cultivate new high-quality lily cultivars with good ornamental and edible traits, hybridization between Lilium brownii var. viridulum and L. davidii var. unicolor was conducted with cut style pollination and embryo rescue. 39 progenies were obtained. FISH with 5S rDNA and 45S rDNA as probes were used to analyze the parents and four progenies. The results showed that all of them are diploid (2n=2x=24); L. brownii has 10 loci of 5S rDNA on chromosomes (CH)-1, -2, -4, -8 and -11 and has 6 loci of 45S rDNA on CH-3, -9 and -10; L. davidii has 6 loci of 5S rDNA distributed on chromosomes CH-8, CH-10, and CH-11 and has 8 loci of 45S rDNA on chromosome CH-1, CH-5, CH-7 and CH-10; all four progenies have 8 loci of 5S rDNA and 7 loci of 45S rDNA, unambiguously, it was concluded that they are true hybrids coming from L. brownii and L. davidii.

A unijunction transistor based on fully-depleted silicon-on-insulator substrate is proposed. The device structure is similar to a junction field effect transistor. By conducting the TCAD simulation, we observe sharp switching and large hysteresis in emitter current-emitter voltage curves with the turn-on voltage linearly controlled by the second base voltage. The operation of the device is mainly determined by the emitter-channel PN junction, which is induced by the backgate voltage. The impact of the backgate voltage on the electrical characteristics is analyzed by changes in the channel potential.

In recent years, the development of miniature gas sensors based on silicon technology is being increasingly emphasized. Most of the devices reported are based on micro-hot plates, but the materials they used are not fully compatible with CMOS and are therefore not suitable for massive production and co-integration with CMOS circuit. In addition, extra process steps are needed to form the sensing device and CMOS circuits separately. In this work, we demonstrate novel gas sensor devices directly based on the MOSFET transistors fabricated in the silicon-on-insulator (SOI) substrate. Both n-type and p-type devices are demonstrated showing opposite sensing polarity under the exposure to NO 2 gas.

In this work, we propose a novel device based on bulk silicon substrate and use it as a dynamic random access memory (DRAM) with TCAD simulation. The operation principle of this device is similar to that of Z 2 -FET which was demonstrated previously in SOI substrate. In our device, LDD doping and gate control are combined to build up the carrier injection barriers which enable feedback mechanism. The designed device shows similar sharp switch and gate-controlled hysteresis in its output characteristics. It is further demonstrated for DRAM application without need of extra capacitor. The DRAM operation shows high speed and reasonably long retention time.

In this work, we review our recent studies on several novel devices built on silicon-on-insulator (SOI) substrates. The sharp-switching Z2- FET , based on a feedback mechanism, has been demonstrated as suitable for many applications. The PISD, capable of in-situ photoelectron sensing, has been used as a one-transistor active pixel sensor (1T-APS). Furthermore, an SOI/MoS 2 heterojunction FET has been demonstrated as both a photodetector with a dynamic response spectrum and as a novel one-transistor wavelength detector (1T-WD) with an output signal sensitive to the variation of wavelength rather than intensity.

Summary Termit Basin belongs to the West African Rift System. The nature of long stretch of regional stress determines the development of normal fault in the whole basin. Antithetic fault block is the most typical style of trap. Hydrocarbon source rocks are developed as the late cretaceous large-scale marine mudstone intrusion. Reservoir beds are developed because lacustrine sand-mudstone alternating beds deposited in Early Paleogene. Caprocks are developed because low velocity mudstone beds deposited in late Paleogene. They formed a generational upper accumulation combination. Faults have an obvious effect to control the hydrocarbon accumulation. Fracture development degree and lateral sealing block are main controlling factors of hydrocarbon accumulation. The development degree of sag determines the distribution of oil and gas enrichment degree. The spatial distribution regularity of fracture decided by regional stress field distribution controls the location of oil and gas enrichment zone and spatial distribution regularity of oil-bearing series in the basin. This study can serve as an record of the breakup of Gondwanaland.

Summary Doseo depression is an underexplored frontier onshore zone, belonging to Central African Rift System. To evaluate the source rock of the depression, we took 112 shale cuttings and 6 oil samples for pyrolysis, elements analysis, vitrinite reflectance, macerals identification, carbon isotopes and mass spectrometry analysis. The results show that three sets of high-quality lacustrine oil-prone source rocks are continuously developed in the Lower Cretaceous of Doseo depression. The organic matter type of three source rock are mainly I-II1, of which Kedeni source rock has the best quality. The maturity of Kedeni source rock is low to medium in the edge of the depression, but in the center of the depression it probably reach the high mature level. Based on the widespread effective source rock in the Doseo depression, the resource potential is considerable in the interbedded sandstone reservoirs of Lower Cretaceous.

In this paper, a finite-time nonlinear control law based on adaptive grey wolf optimization (AGWO) is proposed to obtain a high-efficiency power inverter. Although sliding mode control (SMC) provides robustness against internal parametric changes and external load meddling, the system-state cannot converge to zero in a finite time. The development of a finite-time nonlinear control law (FTNCL) is offered to ensure the finite-time convergence of the system state. But the FTNCL still meets the problem of jitter, which causes harmonic distortion of the output-voltage of the high-efficiency power inverter. In order to effectively suppress the jitter phenomenon, the gain parameters of the FTNCL can be optimally tuned by using the AGWO algorithm. This proposed scheme with the combination of the FTNCL and AGWO has been realized in an actual high-efficiency power inverter operated by a digitized signal processor. Simulations and experiments in a feedback system have revealed that the proposed scheme brings the advantages of fast dynamical reaction, less steady-state error, lessened total harmonic distortion, and relieved jitter.

Wetting behaviors on a hydrophobic nanopatterned surface, which are of primary consideration in the design of superhydrophobic surfaces, are studied on an analytic model that shows the hole-patterned substrate is more favorable for water droplets to nucleate on the inside of holes based on nucleation theory. After droplet nucleation, the transition from Wenzel state to Cassie–Baxter state may occur during the growth stage. The calculation of the free energy of droplets during the growth stage indicates that the wetting transitions depend on the volume of the droplets, and Wenzel state or Cassie–Baxter state depends on the absolute size and relative size of the geometrical morphology of the nanoholes.