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Predicting the thickness distribution of different types of continental lithofacies is a fundamental task for selecting and evaluating continental shale oil-rich zones. Research on oil-bearing conditions, reservoir characteristics, and mobility of different types of lithofacies plays an important role in target area selection and the deployment of horizontal well sections. Based on core observation and logging identification, spectrum analysis of logging data was carried out. Stable astronomical orbital time cycles were introduced to perform spatio-temporal tuning. A high-frequency sequence isochronous lattice for drilling well comparison was established and the planar thickness variation trends of different types of lithofacies in each sequence cycle were quantitatively calculated, providing insights into lithofacies distribution patterns. Research on the 7th member (Chang 7) of Triassic Yan-chang Formation in the Fuxian area of the southern Ordos Basin showed that the natural gamma logging curves contained several sets of astronomical cycle information, among which 6 complete stable 405 kyr long eccentricity astronomical cycles could be identified. Based on the observation of the whole core section of Chang 7 member in well R203 and logging facies characteristics analysis, a reasonable high-frequency isochronous lattice was established for well-to-well comparison. The results showed that mud shale and laminated shale mainly developed in the bottom cyclic strata from Chang 73 to Chang 72 sub-member, and the fine-grained sandstone and siltstone were mostly developed in strata of cycles Ⅳ to Ⅴ from the middle and upper parts of Chang 72 to the bottom of Chang 71. Lateral comparison between wells showed that the mud shale and laminated shale lithofacies in the early cycles were widely distributed. During cycle Ⅰ period, these facies were mainly distributed in the southwest of the study area, and during cycle Ⅱ period, they were distributed in the west and east-northeast, with thicker storage in the central area. The fine-grained sandstone thickness distribution in strata of cycles Ⅳ to Ⅴ was controlled by a northeast-southwest sedimentary system, with a planar distribution from the north-northeast to the south-southwest, further extending to the southwest along wells ZF 27 to ZF 32. Three types of source and reservoir combinations were formed in Chang 7 member. The combination of laminated shale and fine-grained sandstone lithofacies occurred from the middle and upper parts of Chang 73 and Chang 72 sub-members to the lower part of Chang 71 sub-member, primarily distributed in the central-north, north, and northeast parts of the Fuxian area. The shale lithofacies thickness was well developed in Chang 73 sub-member, mainly distributed in the northeast, east, and southwest regions of the Fuxian area.

The shale in the 7th member (Chang 7) of Triassic Yanchang Formation on the southeastern margin of the Ordos Basin is characterized by shallow burial depth, light oil quality, large variability in oil well production capacity, and significant resource potential. Identifying the main controlling factors of reservoir enrichment is key to efficient exploration. Based on analysis results of cast thin sections, physical properties, and scanning electron microscope (SEM) tests of the Chang 7 shale member in the Fuxian area, combined with core, well logging, and seismic data, its layer characteristics are described and the main controlling factors are discussed. The results show that the Chang 7 shale in the research area extensively develops gray, dark gray, and gray black source rocks. The lithology is mainly mudstone and mud shale, with organic matter types mainly classified as type Ⅰ-Ⅱ2. The vitrinite reflectance (Ro) values of source rocks range from 0.81% to 1.10%, indicating strong hydrocarbon generation potential. The sandstone reservoirs are mainly fine-grained feldspathic sandstone, with pore types primarily consisting of intragranular pores, residual intergranular pores, dissolution pores, and primary intergranular pores. Porosity ranges from 2.0% to 16.0%, and permeability ranges from 0.01×10-3 to 1.20×10-3 μm2, indicating tight reservoirs. The oil-bearing properties of the reservoir are impacted by the physical properties of the sandstone interlayers and proximity to faults: coarser-grained reservoirs with better physical properties exhibit better oil and gas bearing potential. Reservoir properties are controlled by two factors, sedimentary microfacies and diagenesis. Subaqueous distributary channel microfacies have the best properties, followed by mouth bar microfacies. Strong early diagenetic chlorite cementation and weak calcite cementation contribute to the formation of sweet spots in the physical properties. The development and nature of faults play a crucial role in the Chang 7 shale oil enrichment. Statistical analysis shows that it is difficult to obtain industrial oil flow when the fault displacement exceeds 10 m and the wellbore is within 1 km of the fault. However, when the fault displacement is less than 7 m or when the wellbore is more than 1 km away from a large fault, industrial oil flow is more easily obtained.

Abstract [Objective] Most intersectional hybrids in Paeonia are triploids and generally sterile, producing a small number of hybrid offspring. Observing the meiotic chromosome behaviors of ‘Bartzella’, an intersectional hybrid with high ornamental value and several hybrid offspring, can provide insight into the formation mechanism of its low fertility. [Methods] The study utilized the anthers of ‘Bartzella’ as materials to observe the meiotic chromosome behaviors of pollen mother cells (PMCs) through the squash method. [Results] (1) In metaphase Ⅰ, a significant number of univalents were formed in ‘Bartzella’ PMCs. In anaphase Ⅰ, various types of chromosomal aneuploid segregation were observed, accounting for up to 89.13%. (2) During the first meiotic division, chromosome bridges and fragments were found in 27.20% of the PMCs; during the second meiotic division, this percentage was increased to 47.68%. (3) In metaphase Ⅱ, spindle positioning abnormalities were relatively common, with fused spindles accounting for 27.06% and tripolar spindles accounting for 12.84%. The meiotic products included up to 72.41% of dyads and 13.43% of triads, which could generate unreduced gametes accounting for about 67%. [Conclusion] Chromosome aneuploidy segregation and loss of chromosome segments during meiosis may be the primary causes of the high sterility of ‘Bartzella’. Fused spindles, tripolar spindles, and abnormal cytokinesis at the end of second meiotic division may result in the production of unreduced gametes. The significant number of unreduced gametes might give ‘Bartzella’ the potential polyploid breeding. However, interploidy hybridization barriers could restrict its hybrid affinity.

Abstract Malicious attacks are often inevitable in cyber-physical systems (CPS). Accuracy in Cyber physical system for position tracking of servos is the major concern now a days. In high precision industrial automation, it is very hard to achieve accuracy in tracking especially under malicious cyber-attacks, control saturations, parametric perturbations and external disturbances. In this paper, we have designed a novel predefined time (PDT) convergence sliding mode adaptive controller (PTCSMAC) for such kind of cyber physical control system. Main key feature of our control is to cope these challenges that are posed by CPS systems such as parameter perturbation, control saturation, and cyber-attacks and the whole system then upgrade to a third-order system to facilitate adaptive control law. Then, we present an adaptive controller based on the novel PDT convergent sliding mode surface (SMS) combined with a modified weight updated Extreme Learning Machine (ELM) which is used to approximate the uncertain part of the system. Another significant advantage of our proposed control approach is that it does not require detailed model information, guaranteeing robust performance even when the system model is uncertain. Additionally, our proposed PTCSMAC controller is nonsingular regardless of initial conditions, and is capable of eradicating the possibility of singularity problems, which are frequently a concern in numerous CPS control systems. Finally, we have verified our designed PTCSMAC control law through rigorous simulations on CPS seeker servo positioning system and compared the robustness and performance of different existing techniques.

Abstract In this study, two new kaurane diterpenes (16, 17), together with 12 lignans (1–12), a triterpene (15), and two other compounds (13, 14) were isolated from the woods of Agathis dammara. The structure of the new compound was determined by HR ESIMS and 1D/2D NMR spectroscopy, and its absolute configuration was determined by electronic circular dichroism (ECD) exciton chirality method. Compounds 5, 11, 14 exhibit significant hypoglycaemic activity in zebrafish, and their mechanism of action is to enhance glucose uptake in zebrafish. Graphical Abstract

Abstract Achieving accurate position tracking for robotics and industrial servo systems is an extremely challenging task, particularly when dealing with control saturation, parameter perturbation, and external disturbance. To address these challenges, a predefined time convergent sliding mode adaptive controller (PTCSMAC) has been proposed for a permanent magnet linear motor (PMLM). A novel sliding mode surface (SMS) with predefined time convergence PDTC has been constructed, which ensures that the error converges to zero within the prescribed time. The system not only meets the expected performance standards but also has a uniformly bounded motor speed. The trajectory tracking error in SMS is proven to converge to zero within the predefined time. This predefined time stability of the closed-loop system has been demonstrated by using the Lyapunov stability criterion with PDTC. The convergence time (CT) can be arbitrarily set, and the upper bound of it is not affected by the initial value and control parameters of the system. A new updated version of extreme learning machine (ELM) is introduced to approximate the uncertain part of the system based on PDTC. The ELM is also provided with the hyperbolic tangent function to estimate the saturation constraint. This is done by converting the function into a linear function concerning the unconstrained control input variable. Then, based on established stability, a novel sliding mode adaptive controller (PTCSMAC) with predefined time convergence is designed. The convergence time (CT) of the controller is unaffected by the initial conditions as well as the control parameters. The rigorous numerical simulations on the PMLM model with complex disturbances verify the strong robustness and high-precision tracking characteristic of the proposed control law.

Objective Commercial oil accumulation in the Jinghe Oilfield of the Southwest Ordos Basin was primarily found in the Northeast area. Previous studies have shown that oil mainly sourced from the oil shale in Member 7 of the Yanchang Formation. However, whether the oil comes from the source rocks spatially located in the Jinghe Oilfield or the basin center has not been determined, which inhibits further exploration of the Jinghe Oilfield. Methods In this paper, the hydrocarbon generation and expulsion history of source rocks in Member 7 of the Yanchang Formation in different tectonic parts of the Jinghe Oilfield and in the basin center have been reconstructed through basin simulation. Then, the accumulation periods of oil in the Yanchang Formation reservoir have been identified using fluid inclusion technology. Results The time window comparison of the oil accumulation in reservoir and the hydrocarbon generation and expulsion of source rocks show that oil in the Jinghe Oilfield limitedly came from the source rocks beneath the Jinghe Oilfield but more widely came from source rocks in the basin center. The oil in the Jinghe Oilfield generally shows the migration direction from Northeast to Southwest. Conclusion Therefore, unlike the traditional model of short-distance vertical migration, a new model can be established as that, the oil in the Jinghe Oilfield mainly laterally migrated from the hydrocarbon kitchen in the basin center along the strike-slip fault belt. The research results can provide an important reference for the prediction of hydrocarbon accumulation zones in the Jinghe Oilfield.

Pore-throat size distribution is a key factor controlling the storage capacity and percolation potential of the tight sandstone reservoirs. However, the complexity and strong heterogeneity make it difficult to investigate the pore structure of tight sandstone reservoirs by using conventional methods. In this study, integrated methods of casting thin section, scanning electron microscopy, high-pressure mercury intrusion (HPMI), and constant-pressure mercury intrusion (CPMI) were conducted to study the pore-throat size distribution and its effect on petrophysical properties of the Shanxi Formation tight sandstones in the northern Ordos Basin (China). Results show that pore types of the Shanxi tight sandstone reservoirs include intergranular pores, dissolution pores, intercrystalline micropores, and microfracture, while the throats are dominated by sheet-like and tube-shaped throats. The HPMI-derived pore-throat size ranges from 0.006 to 10 μm, and the pore-throats with a radius larger than 10 μm were less frequent. The pore body size obtained from CPMI shows similar characteristics with radii ranging from 100 to 525 μm, while the throat size varies greatly with radii ranging from 0.5 to 11.5 µm, resulting in a wide range of pore-throat radius ratio. The full range of pore size distribution curves obtained from the combination of HPMI and CPMI displays multimodal with radii ranging from 0.006 to 525 µm. Permeability of the tight sandstone reservoirs is primarily controlled by relatively larger pore throats with small proportions, and the permeability decreases as the proportions of smaller pore-throats increase. The pervading nanopores in the tight gas sandstone reservoirs contribute little to the permeability but play an important role in the reservoir storage capacity. A new empirical equation obtained by multiple regression indicates that r 15 (pore-throat size corresponding to 15% mercury saturation) is the best permeability estimator for tight gas sandstone reservoirs, which yields the highest correlation coefficient of 0.9629 with permeability and porosity.

A set of favorable source-reservoir-caprock assemblage was found in the Upper Paleozoic transitional facies in the Hangjinqi area of the Ordos Basin, and the large-scale Dongsheng gas field has been discovered. A small amount of crude oil has been produced from the Lower Shihezi Formation reservoir in the area; however, the origin and exploration prospect of the oil are unclear. Based on the studies including physical property, n-alkanes distributions, biomarker compositions, and carbon isotopic ratios, the origin and exploration prospect of the crude oil has been discussed. Results indicate that the Upper Paleozoic crude oil from the Hangjinqi area is mature oil with a low sulfur content and a high wax content, and the steranes are dominated by terrestrial plants and assisted by a small amount of aquatic organism. The Pr/Ph ratio is 2.16-2.26, and the diasteranes and rearranged hopanes are in high contents with a relative low content of gammacerane. The carbon isotopic ratios of the oil range from -27.7‰ to -26.8‰, [JP+1]and the carbon isotopic[JP]compositions of individual n-alkanes are heavy at first and then become light with the increasing of carbon numbers. These characteristics suggest that the oil was generated by the dark mudstone in terrigenous coal measures under weak oxidation environment. The comprehensive analysis combining organic petrography, hydrocarbon generation simulation, and pyrolysis of source rocks in the Shanxi Formation indicates that, the dark mudstone in the Permian Shanxi Formation in the Hangjinqi area displays a certain amount of oil generation potential. In combination with the location of oil producing wells and the spatial distribution of source rocks, the dark mudstone in the Shanxi Formation might be the potential source rocks for the produced oil. The oil exploration of the Upper Paleozoic strata in the Hangjinqi area deserves attention as suggested by the favorable conditions of source-reservoir-caprock assemblage, and the adjacent areas of the Borjianghaizi fault are potential favorable areas for oil accumulation.

The Permian stratum in Hangjinqi area is one of the important fields to increase gas reserves and outputs in the Ordos Basin in recent years. The studies of the origin and source of formation water are still insufficient due to the complexity of relationship between gas and formation water. Based on the analysis of major components, trace elements, as well as hydrogen and oxygen isotopes, the indication of geochemical characteristics for the source of formation water is then revealed. The Permian formation water in Hangjinqi area is mainly of CaCl2 type, and the average total dissolved solids (TDS) of formation water to the north and south of the Borjianghaizi fault are 52.1 and 41.9 g/L, respectively. Different water chemical parameters indicate favorable formation sealing conditions, and the formation water has experienced strong concentrated metamorphism with beneficial preservation conditions for natural gas. The formation water is mainly terrigenous one after evaporation and concentration, and the stratum has experienced albitization of plagioclase and dolomitization of cements. The δD and δ18O values of the formation water are mainly in the ranges of -81‰ to -75‰ and -12.1‰ to -8.8‰, respectively, suggesting weaker water-rock interaction than that in the Sulige gas field. Due to the mixing of condensate water in regional uplift since the Late Cretaceous or the seepage of surface water along faults, a small number of formation water samples display more negative δD values.

Hypertriglyceridemia is caused by defects in triglyceride metabolism and generally manifests as abnormally high plasma triglyceride levels. Although the role of hypertriglyceridemia may not draw as much attention as that of plasma cholesterol in stroke, plasma triglycerides, especially nonfasting triglycerides, are thought to be correlated with the risk of ischemic stroke. Hypertriglyceridemia may increase the risk of ischemic stroke by promoting atherosclerosis and thrombosis and increasing blood viscosity. Moreover, hypertriglyceridemia may have some protective effects in patients who have already suffered a stroke via unclear mechanisms. Therefore, further studies are needed to elucidate the role of hypertriglyceridemia in the development and prognosis of ischemic stroke.

High precision demands in a large number of emerging robotic applications strengthened the role of the modern control laws in the position control of the Permanent Magnet Synchronous Motor (PMSM) servo system. This paper proposes a learning-based adaptive control approach to improve the PMSM position tracking in the presence of the friction uncertainty. In contrast to most of the reported works considering the servos operating at high speeds, this paper focuses on low speeds in which the friction stemmed deteriorations become more obvious. In this paper firstly, a servo model involving the Stribeck friction dynamics is formulated, and the unknown friction parameters are identified by a genetic algorithm from the offline data. Then, a feedforward controller is designed to inject the friction information into the loop and eliminate it before causing performance degradations. Since the friction is a kind of disturbance and leads to uncertainties having time-varying characters, an Adaptive Proportional Derivative (APD) type Iterative Learning Controller (ILC) named as the APD-ILC is designed to mitigate the friction effects. Finally, the proposed control approach is simulated in MATLAB/Simulink environment and it is compared with the conventional Proportional Integral Derivative (PID) controller, Proportional ILC (P-ILC), and Proportional Derivative ILC (PD-ILC) algorithms. The results confirm that the proposed APD-ILC significantly lessens the effects of the friction and thus noticeably improves the control performance in the low speeds of the PMSM.

Abstract Background To aid clinicians strategizing treatment for upper esophageal squamous cell carcinoma (ESCC), this retrospective study investigated associations between primary gross tumor volume (GTVp) and prognosis in patients given surgical resection, radiotherapy, or both resection and radiotherapy. Methods The population comprised 568 patients with upper ESCC given definitive treatment, including 238, 216, and 114 who underwent surgery, radiotherapy, or combined radiotherapy and surgery. GTVp as a continuous variable was entered into the multivariate Cox model using penalized splines (P-splines) to determine the optimal cutoff value. Propensity score matching (PSM) was used to adjust imbalanced characteristics among the treatment groups. Results P-spline regression revealed a dependence of patient outcomes on GTVp, with 30 cm3 being an optimal cut-off for differences in overall and progression-free survival (OS, PFS). GTVp ≥30 cm3 was a negative independent prognostic factor for OS and PFS. PSM analyses confirmed the prognostic value of GTVp. For GTVp

Nanoliposome is a useful dosage form to increase solubility and absorption of simvastatin (SMV), and consequently improves its therapeutic effects. However, in vivo toxicity of SMV could also be elevated accompanied by the absorption enhancement, which is a decisive factor for the clinical application of SMV nanoliposome (SMV-Lipo), but has not been studied systematically and reported so far. In this study, organ toxicity of SMV-Lipo was evaluated in mice in the presence and absence of isoproterenol and compared to those of free SMV. Results demonstrated that compared to free SMV, the SMV-Lipo administrated at an equal dose of 25 mg/kg/d led to severe myocardiotoxicity, hepatotoxicity at baseline and more pronounced liver injury with elevation of alanine aminotransferase. In addition, muscular adverse effect was also observed in SMV-Lipo treated group but not in SMV group. Pharmacokinetic studies revealed that compared to free SMV, the SMV-Lipo administration significantly improved the plasma SMV concentration, and the oral bioavailability was 6.5 times of free SMV. Notably, when the dosage of free SMV increased to 50 mg/kg/d, yielding the comparable plasma concentration as SMV-Lipo given at 25 mg/kg/d, the myocardiotoxicity was observed in free SMV treated mice as well, which further confirmed that the enhanced absorption of SMV by the nanoliposomal formulation resulted in more severe myocardiotoxicity than the equal dose of free SMV. Keywords: Simvastatin, Nanoliposome, Myocardiotoxicity, Muscular toxicity, Hepatotoxicity

Summary: T regulatory (Treg) cells are crucial to maintain immune tolerance and repress antitumor immunity, but the mechanisms governing their cellular redox homeostasis remain elusive. We report that glutathione peroxidase 4 (Gpx4) prevents Treg cells from lipid peroxidation and ferroptosis in regulating immune homeostasis and antitumor immunity. Treg-specific deletion of Gpx4 impairs immune homeostasis without substantially affecting survival of Treg cells at steady state. Loss of Gpx4 results in excessive accumulation of lipid peroxides and ferroptosis of Treg cells upon T cell receptor (TCR)/CD28 co-stimulation. Neutralization of lipid peroxides and blockade of iron availability rescue ferroptosis of Gpx4-deficient Treg cells. Moreover, Gpx4-deficient Treg cells elevate generation of mitochondrial superoxide and production of interleukin-1β (IL-1β) that facilitates T helper 17 (TH17) responses. Furthermore, Treg-specific ablation of Gpx4 represses tumor growth and concomitantly potentiates antitumor immunity. Our studies establish a crucial role for Gpx4 in protecting activated Treg cells from lipid peroxidation and ferroptosis and offer a potential therapeutic strategy to improve cancer treatment.

BackgroundPathophysiological vascular remodeling in response to disturbed flow with low and oscillatory shear stress (OSS) plays important roles in atherosclerosis progression. Pomegranate extraction (PE) was reported having anti-atherogenic effects. However, whether it can exert a beneficial effect against disturbed flow-induced pathophysiological vascular remodeling to inhibit atherosclerosis remains unclear. The present study aims at investigating the anti-atherogenic effects of pomegranate peel polyphenols (PPP) extraction and its purified compound punicalagin (PU), as well as their protective effects on disturbed flow-induced vascular dysfunction and their underlying molecular mechanisms.MethodsThe anti-atherogenic effects of PPP/PU were examined on low-density lipoprotein receptor knockout mice fed with a high fat diet. The vaso-protective effects of PPP/PU were examined in rat aortas using myograph assay. A combination of in vivo experiments on rats and in vitro flow system with human endothelial cells (ECs) was used to investigate the pharmacological actions of PPP/PU on EC dysfunction induced by disturbed flow. In addition, the effects of PPP/PU on vascular smooth muscle cell (VSMC) dysfunction were also examined.ResultsPU is the effective component in PPP against atherosclerosis. PPP/PU evoked endothelium-dependent relaxation in rat aortas. PPP/PU inhibited the activation of Smad1/5 in the EC layers at post-stenotic regions of rat aortas exposed to disturbed flow with OSS. PPP/PU suppressed OSS-induced expression of cell cycle regulatory and pro-inflammatory genes in ECs. Moreover, PPP/PU inhibited inflammation-induced VSMC dysfunction.ConclusionPPP/PU protect against OSS-induced vascular remodeling through inhibiting force-specific activation of Smad1/5 in ECs and this mechanism contributes to their anti-atherogenic effects.

Aiming at the situation that complex natural scene text is difficult to recognize a scene text recognition method based on an encoder-decoder framework is proposed. The method converts the natural text recognition into a sequence mark by combining the connection time classification (CTC) and attention mechanism under the encoder-decoder framework, in order to overcome the problem of character segmentation, using the correlation between image and text sequence. First of all, a convolutional neural network (CNN) is used to generate an ordered feature sequence from the entire word image. Then, the generated feature sequence is feature-coded using the bidirectional long short-term memory (Bi-LSTM) network. Finally, an integrated module of the CTC and attention mechanism is designed to decode and output the text sequence. The experiments show that compared with the comparison method, the recognition accuracy of the method is improved obviously.

Deep learning achieves substantial improvements in face detection. However, the existing methods need to input fixed-size images for image processing and most methods use a single network for feature extraction, which makes the model generalization ability weak. In response to the above problems, our framework leverages a cascaded architecture with three stages of deep convolutional networks to improve detection performance. The network can predict face in a coarse-to-fine manner. We replace the standard convolution with a combination of separable convolution and residual structure in the network. Extensive experiments on the challenging FDDB and WIDER FACE benchmarks demonstrate that our method achieves competitive accuracy to the state-of-the-art techniques while keeps real-time performance.

Femtosecond laser filament-generated plasma can generate electromagnetic pulses (EMPs). These pulses may reduce the instrument’s precision, and, hence, influence the accuracy of the experimental results. They may even cause widespread disruption by disabling of the electronic control systems or distribution networks of power plants. This study investigated the characteristics of EMPs generated from the interaction of filament-generated plasmas with a solid target in air. In this study, ultrafast laser filamentation was used to produce plasma, which was focused on a 3 mm-thick aluminum (Al) alloy target for interaction, and the spatial distribution and main contributors of the EMPs were systematically and extensively studied. The results showed that the EMPs generated from ultrafast laser filament interaction with the Al alloy target had the following characteristics: the EMP energy generated from laser filament interaction with solid targets is tens of times higher than that generated only from the femtosecond laser filament; the maximum EMP signals appeared at a 20°–80°detection angle. The relationship between the energy of EMPs and the width and energy of the laser pulses is presented and discussed. These findings are beneficial for gaining insight into the EMP generation mechanism, spatial distribution, and transmission, and for providing more information for the design of EMPs’ shielding.

The electron density profile on a plasma surface has a decisive influence on the mechanism and characteristics of the plasma high-order harmonic generation. When the pre-pulse has a similar spatial and temporal distribution as the main laser pulse, the plasma surface on the target will expand to form a convex profile of the similar size as the focal spot of the main pulse. We experimentally observed that the divergence of the harmonics generated by the relativistic laser light incident on a silica target has a saddle-shaped structure. The two-dimensional particle-in-cell simulation with convex plasma surfaces explains the experimental results very well and infers a 0.12λL plasma scale length around the center of the convex profile. Further, we qualitatively explained that the asymmetry of the saddle-shaped harmonic divergence is caused by oblique incidence.

Hypercholesterolemia is one of the independent risk factors for the development of cardiovascular diseases such as atherosclerosis. The treatment of hypercholesterolemia is of great significance to reduce clinical cardiovascular events and patient mortality. Simvastatin (SIM) and ezetimibe (EZE) are commonly used clinically as cholesterol-lowering drugs; however, their treatment efficacy is severely affected by their poor water solubility and low bioavailability. In this study, SIM and EZE were made into a co-amorphous system to improve their dissolution, oral bioavailability, storage stability, and cholesterol-lowering effects. The SIM-EZE co-amorphous solids (CO) were prepared successfully using the melt-quenched technique, and the physicochemical properties of CO were characterized accordingly, which exhibited improved physical stability and faster dissolution release profiles than their physical mixture (PM). In the pharmacokinetic study, the SIM-EZE CO or PM was given once by oral gavage, and mouse blood samples were collected retro-orbitally at multiple time points to determine the plasma drug concentrations. In the pharmacodynamic study, low-density lipoprotein receptor-deficient (LDLr−/−) mice were fed with a high-fat diet (HFD) for two weeks to establish a mouse model of hypercholesterolemia. Using PM as a control, we investigated the regulation of CO on plasma lipid levels in mice. Furthermore, the mice feces were collected to determine the cholesterol contents. Besides, the effect of EZE on the NPC1L1 mRNA expression level in the mouse intestines was also investigated. The pharmacokinetics results showed that the SIM-EZE CO has improved bioavailability compared to the PM. The pharmacodynamic studies showed that SIM-EZE CO significantly increased the cholesterol-lowering effects of the drugs compared to their PM. The total cholesterol excretion in the mouse feces and inhibitory effect on NCP1L1 gene expression in the mouse intestines after being given the SIM-EZE CO were more dramatic than the PM. Our study shows that the SIM-EZE CO prepared by the melt-quenched method can significantly improve the stability, bioavailability, and cholesterol-lowering efficacy with excellent development potential as a new drug formulation.

Lie symmetry analysis of differential equations proves to be a powerful tool to solve or at least reduce the order and nonlinearity of the equation. Symmetries of differential equations is the most significant concept in the study of DE’s and other branches of science like physics and chemistry. In this present work, we focus on Lie symmetry analysis to find symmetries of some general classes of KS-type equation. We also compute transformed equivalent equations and some invariant solutions of this equation.

The vague understanding of the coupling relationship among natural gas charging, reservoir densification, and pressure evolution restricted the tight gas exploration in the Lower Shihezi Formation of the Hangjinqi area, north Ordos Basin. In this study, the quantitative porosity evolution model, the pressure evolution process, and the natural gas charging history of tight sandstone reservoirs were constructed by integrated investigation of the reservoir property, the thin section, SEM and cathode luminescence observations, the fluid inclusion analysis and the 1D basin modeling. The results show that the compaction and cementation reduced the primary porosity by 21.79% and 12.41%, respectively. The densification of the reservoir occurred at circa 230 Ma, which was before the natural gas charging time from 192 to 132 Ma. The paleo-overpressure within the tight reservoirs occurred since the Middle Jurassic with the pressure coefficients between 1.1 and 1.55. The continuous uplifting since the Late Cretaceous resulted in the under- and normal-pressure of the Lower Shihezi Formation with the pressure coefficients ranging from 0.67 to 1.05. The results indicate that the densification of the reservoirs was conducive to the formation of paleo-pressure produced by gas generating. The gas predominantly migrated vertically, driven by gas expansion force rather than buoyance and displaced the pore water in the reservoirs near source rocks.

This paper presents a flux-weakening model predictive control (FW-MPC) for the interior permanent magnet synchronous motor (IPMSM) drive system. The FW control is a strategy to extend the IPMSM’s operating region. However, the primary FW needs to track the torque reference and maximize the electrical torque per current amplitude with the current and voltage limitations. The two objects make it impossible to solve the FW problem using the optimization method. We proposed an equivalent optimization problem to simplify the complex FW problem, including two objective functions. The MPC is selected as the controller due to its high robustness and transient performance. The constraints from the equivalent optimization problem are added in the MPC to control the IPMSM in the FW region. The simulation and experiment results indicate that the proposed FW-MPC is feasible and effective in driving the IPMSM in the FW region. The proposed FW-MPC can find the optimal point with the maximum electrical torque satisfying the current and voltage limitations. Therefore, the proposed FW-MPC can extend the IPMSM’s operating region, benefiting the IPMSM’s application.

Tilianin, a representative flavonoid ingredient of Dracocephalum moldavica L., has been used to treat several diseases for centuries, including atherosclerosis (AS). However, pharmacological mechanisms underlying its biological functions remain elusive. In the present study, we investigated the anti-AS mechanisms of tilianin through establishing in vitro models using three types of cells that contributed to AS progression, including macrophage, vascular smooth muscle cells and human umbilical vein endothelial cells, which were proved to be involve in LPS/TNF-α/oxidized low density lipoprotein (ox-LDL)-induced inflammation and ox-LDL induced foam cell formation. Our results indicate that tilianin significantly suppressed LPS induced inflammatory responses on macrophage and remarkably inhibited TNF-α induced VSMCs proliferation and migration. Furthermore, the anti-inflammatory effect of tilianin on macrophages and VSMCs was proved to be mainly by downregulating TNF-α/NF-κB pathway. Moreover, our results demonstrate that tilianin significantly ameliorated ox-LDL induced macrophages oriented foam cells formation through repressing mRNA expression of SR-A1 and inducting the expression of genes related to cholesterol efflux including SRB-1 and ABCA1. However, tilianin had no effect on ox-LDL induced HUVECs injury.

A novel Podoviridae lytic phage AJO2, specifically infecting Acinetobacter johnsonii, was isolated from bulking activated sludge. The one-step growth experiment showed that the latent period and burst size of AJO2 were estimated to be 30 min and 78.1 phages per infected cell, respectively. The viability test indicated that neutral conditions (pH 6–8) were table for AJO2 survival, while it was sensitive to high temperature (≥60°C) and ultraviolet treatment (254 nm). Genomic sequencing revealed that the AJO2 had a linearly permuted, double-stranded (ds) DNA consisting of 38,124 bp, with the G+C content of 41 mol%. A total of 58 putative open reading frames (ORFs), 11 pairs of repeats and 11 promoters were identified. The AJO2 genome had a modular gene structure which shared some similarities to those of A. baumanii phages. However, genomic comparative analysis revealed many differences among them, and novel genes were identified in the AJO2 genome. These results contribute to subsequent researches on the interaction between bacteriophages and hosts in wastewater treatment, especially during the bulking period. Additionally, the newly isolated phage could be a good candidate as a therapeutic agent to control nosocomial infections caused by A. johnsonii.

Measurement of the matched spot size in the hydrogen-filled capillary discharge waveguide based on the spot size oscillation of a collimated laser is presented in this paper. The spot size oscillation trace is retrieved from the laser modes measured at the exits of discharged capillaries of different lengths under the same discharge conditions. With the gas pressure, peak discharge electric current and capillary radius fixed, the radial density profiles are identical in all the discharged capillaries. The measured laser modes are equivalent to the evolution at discrete positions in a long plasma channel. Compared to former researches based on the spot size at the capillary exit, this method is not affected by the multiple solution problem. The use of a collimated laser eliminates the influences of the divergence angle on the fitting accuracy. By this means, the matched spot sizes of hydrogen-filled capillary discharge waveguides under different gas pressures (5-20mbar) are measured. The results can provide a spot size reference for the laser wakefield accelerator guided in a plasma channel.

We experimentally demonstrated the generation of narrow energy-spread electron beams with enhanced energy levels using a hybrid laser-plasma wakefield accelerator. An experiment featuring two-color electron beams showed that after the laser pump reached the depletion length, the laser-wakefield acceleration (LWFA) gradually evolved into the plasma-driven wakefield acceleration (PWFA), and thereafter, the PWFA dominated the electron acceleration. The energy spread of the electron beams was further improved by energy chirp compensation. Particle-in-cell simulations were performed to verify the experimental results. The generated monoenergetic high-energy electron beams are promising to upscale future accelerator systems and realize monoenergetic γ -ray sources.

The evolution of mechanical properties of a third-generation Al–Cu–Li alloy, AA2050, with different initial tempers (as-quenched WQ, naturally aged T34 and peak-aged T84) during creep-ageing has been investigated in this study. A set of creep-ageing tests was carried out under 150 MPa at 155 °C with different durations for all initial temper conditions and tensile tests were performed subsequently to acquire the main mechanical properties of the creep-aged alloys, including the yield strength, ultimate tensile strength and uniform elongation. The evolution of these mechanical properties during creep-ageing has been discussed in association with precipitation behaviour of AA2050 alloys with different initial tempers. The results indicate that the T34 alloy is the best choice for creep age forming (CAF) applications among these initial tempers, as it provides better yield strength and uniform elongation concurrently after creep-ageing. In addition, a work hardening rate analysis has been carried out for all the creep-aged alloys, helping to understand the detailed dislocation/precipitate interaction mechanisms during plastic deformation in the creep-aged AA2050 alloys with WQ, T34 and T84 initial tempers.

This paper presents a model for analyzing a five-phase fractional-slot permanent magnet tubular linear motor (FSPMTLM) with the modified winding function approach (MWFA). MWFA is a fast modeling method and it gives deep insight into the calculations of the following parameters: air-gap magnetic field, inductances, flux linkages, and detent force, which are essential in modeling the motor. First, using a magnetic circuit model, the air-gap magnetic density is computed from stator magnetomotive force (MMF), flux barrier, and mover geometry. Second, the inductances, flux linkages, and detent force are analytically calculated using modified winding function and the air-gap magnetic density. Finally, a model has been established with the five-phase Park transformation and simulated. The calculations of detent force reveal that the end-effect force is the main component of the detent force. This is also proven by finite element analysis on the motor. The accuracy of the model is validated by comparing with the results obtained using semianalytical method (SAM) and measurements to analyze the motor’s transient characteristics. In addition, the proposed method requires less computation time.

Application of a newly developed flexible forming tool to creep age forming (CAF) process has been investigated in this study. The flexible tool mainly consists of sparsely distributed forming pins, splines and elastomeric sheet. The effect of key factors related to the forming tool on the shape of the formed parts has been studied through various CAF experiments. The key factors investigated in this study include: the interval between forming pins, the arrangement of pins, the accuracy requirement of pin height and the material of splines. It has been found that reducing the interval between pins can efficiently smooth the shape of CAFed plates. The feasibility of asymmetric arrangement of pins has been proven, which can decrease the number of used pins, reduce tool weight, and increase efficiency. The forming results are very sensitive to the pin height, thus the experimental set-up error should be carefully controlled. Additionally, compared with mild steel, spring steel is more suitable as the spline material.

The evolution of mechanical properties of a third generation Al-Cu-Li alloy, AA2050, with different initial tempers (T34 and as-quenched (WQ)) during creep-ageing has been investigated and analysed in this study. A set of creep-ageing tests under 150 MPa at 155 °C for up to 24 h was carried out for both initial temper conditions and tensile tests were performed subsequently to acquire the main mechanical properties of the creep-aged alloys, including the yield strength, ultimate tensile strength (UTS) and uniform elongation. Precipitation behaviour of the T34 and WQ AA2050 alloys has been summarised and successfully explains the detailed evolutions of the obtained mechanical properties of the alloy with these two initial tempers during creep-ageing. The results indicate that the T34 alloy can be a better choice for creep age forming (CAF) process compared with WQ alloy, as it provides better yield strength and uniform elongation properties concurrently after creep-ageing. In addition, a work hardening rate analysis has been carried out for all the creep-aged alloys, helping to reveal the detailed dislocation/precipitates interaction mechanisms during plastic deformation in the creep-aged T34 and WQ AA2050 alloys.

By controlling electron injection into the second period of the laser-driven wakefield in a downward density ramp, a high-quality low-energy electron beam can be accelerated in a short segment of high-density plasma. After a second downward density ramp followed by a low-density plasma plateau, the pre-accelerated electron beam can be seeded into the first period of the laser-driven wakefield for cascaded acceleration at an optimized phase. A monoenergetic electron beam with peak energy of ∼1.2 GeV can be generated from plasma with a length of 12 mm and density of 9 × 10 ^17 cm ^−3 , driven by a laser pulse with peak power of 77 TW. By modifying the acceleration stage comprising several density-ascending plasma segments, the peak energy of the quasi-monoenergetic electron beam can be efficiently increased by about 50% via a quasi-phase-stable multiple-cascade acceleration scheme.