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Rationale: Natural monomer flavors can modify the taste of cigarettes. However, no report was published to establish the quality control method for their chemical compositions. Methods: In this study, licorice, a traditional natural monomer flavor used in tobacco aroma processing, was selected, and the fingerprint was developed by high‐performance liquid chromatography (HPLC). Next, the chemical markers of samples from different places of origin were discovered by multivariate statistical analysis. Then, its chemical constituents were identified by combination of HPLC‐Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR‐MS), direct infusion FT‐ICR‐MS (DI‐FT‐ICR‐MS), and the technology of isotopic fine structures (IFSs). Moreover, its characteristic constituents were quantitatively analyzed using HPLC. Results: The 14 common peaks were assigned in the fingerprint, and 8 of them were considered as qualitative markers by multivariate statistical analysis. A total of 42 chemical constituents were detected using HPLC‐FT‐ICR‐MS, and 13 of them were unambiguously identified by references. Meanwhile, the elemental compositions of other eight unknown chemical components were decisively determined using IFSs. Subsequently, the contents of five characteristic constituents in 11 batches of samples were determined. Conclusions: The integration strategy established here can discover and quantify the chemical markers for improving the quality control standard of natural monomer flavor of licorice. It is expected that the strategy will be valuable for further quality control of other natural monomer flavors in Chinese tobacco industry. [ABSTRACT FROM AUTHOR]

This article proposes a design of a tracking controller for autonomous articulated heavy vehicles (AAHVs) using a nonlinear model predictive control (NLMPC) technique. Despite economic and environmental benefits in freight transportation, articulated heavy vehicles (AHVs) exhibit poor directional performance due to their large sizes, multi-unit vehicle configurations, and high centers of gravity (CGs). AHVs represent a 7.5 times higher risk of traffic accidents than single-unit vehicles (e.g. rigid trucks, cars, etc.) in highway operations. Human driver errors cause about 94% of traffic collisions. However, little attention has been paid to autonomous driving control of AHVs. To increase the safety of AHVs, we design a novel NLMPC-based tracking controller for an AHV, that is, a tractor/semi-trailer combination, and this tracking controller is distinguished from others with the feature of controlling both the lateral and longitudinal motions for both the leading and trailing units. To design the tracking controller, a new prediction AHV model is developed, which represents both the lateral and longitudinal dynamics of the vehicle and captures its rearward amplification feature over high-speed evasive maneuvers. With the proposed tracking controller, the AAHV tracks the predefined reference path and follows a planned forward-speed scheme. Co-simulation demonstrates the effectiveness and robustness of the proposed NLMPC tracking controller. [ABSTRACT FROM AUTHOR]

Shanghai is one of the largest cities in China and has the highest proportion of inbound travelers in the world. The HIV (human immunodeficiency virus) infection status of this population can reflect the global HIV epidemic trend to a certain extent. Therefore, we conducted a retrospective epidemic survey to clarify the prevalence and characteristics of HIV-1 infection among inbound travelers applying for Shanghai residency. The retrospective cohort analysis included a total of 50,830 inbound tourists/travelers who applied for Shanghai residency from 2005 to 2016. HIV-1 infection rates were determined based on HIV-1 antibody testing. Among all the recruited inbound travelers, 245 were HIV-1 positive, with an infection rate of 0.48%. The detection rate of HIV in males was significantly higher than in females (χ2 = 62.584, P < 0.0001). Those aged 18–30 years, 31–40 years, and >40 years accounted for 34.3%, 39.6%, and 26.1% of the infected population, respectively. Although the annual detection rates were different, the trend analysis results showed no increase in HIV-1 prevalence rates among the sampling years (Cochran-Armitage Z = 2.543, P = 0.111). Proportions of individuals infected through homosexual transmission increased over the study period (Cochran-Armitage Z = 5.41, P < 0.001), while the proportion infected through heterosexual declined over time (Cochran-Armitage Z = 3.38, P = 0.001). The rate and characteristics of HIV-1 infection among foreign applicants for residency in Shanghai were identified in the study. The results provide the necessary epidemiological data for monitoring the HIV-1 epidemic among international entry travelers and contribute to establishing relevant policies and regulations for HIV control and prevention. [ABSTRACT FROM AUTHOR]

Ferroptosis is a type of regulatory cell death, caused by excessive lipid peroxidation This study aimed to explore whether ionizing radiation could induce ferroptosis in glioma cells and whether carbonic anhydrase 9 (CA9) knockdown could enhance the killing effect of ionizing radiation on hypoxic glioma cells through ferroptosis. The protein levels of Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) were detected by Western blot in glioma cells irradiated by different doses of X-ray. The relative mRNA levels of ferroptosis markers and intracellular iron-associated proteins were detected by Real-time qPCR. Lipid peroxidation of glioma cells was detected by oxidation-sensitive probe C11-BODIPY581/591 staining. CCK-8 Assay was used to detect cell viability after X-ray irradiation. Cloning formation assay was used to assess the radiosensitivity of glioma cells. The exposure of cell surface calreticulin was measured by immunofluorescence staining. X-ray induced lipid peroxidation and ferroptosis markers expression in U251 and GL261 glioma cells. Knockdown of CA9 in hypoxic glioma cells significantly altered the expression of iron regulation-related proteins and enhanced X-ray-induced ferroptosis and radiosensitivity. The ferroptosis inhibitor significantly improved the survival of cells irradiated by X-ray, while ferroptosis inducers (FINs) enhanced the lethal effect of X-ray on cells. Enhancing ferroptosis in glioma cells promoted the exposure and release of damage-associated molecular patterns (DAMPs). Ionizing radiation can induce ferroptosis in glioma cells. CA9 knockdown can enhance the radiosensitivity of hypoxic glioma cells and overcome the resistance of ferroptosis under hypoxia. Enhancing ferroptosis will become a new idea to improve the efficacy of radiotherapy for glioma. [ABSTRACT FROM AUTHOR]

After irradiation, double-stranded DNA leaked into the cytoplasm activates the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway, leading to the production of type I interferon (IFNI). In this study, we sought to probe the effect of ionizing radiation on activity of cGAS-STING-IFNI pathway in normoxic or hypoxic glioma cells and explore a more effective method to activate the signaling pathway, thereby activating the anti-tumor immune response and improving the therapeutic effect of radiotherapy for glioma. Human glioma cells U251 and T98G cultured in normoxia or hypoxia (1% O2) were irradiated with different doses of X-ray. The relative expressions of cGAS, IFN-I stimulated genes (ISGs), and three-prime repair exonuclease 1 (TREX1) were detected by qPCR. The expression levels of interferon regulatory factor 3 (IRF3) and p-IRF3 proteins were detected by Western blot. The production of cGAMP and IFN-β in the supernatant was detected by ELISA assay. U251 and T98G cell lines with stable knockdown of TREX1 were established after transfection with lentivirus vectors. EdU cell proliferation assay was used to screen suitable metal ions concentrations. The phagocytosis of DCs was observed by immunofluorescence microscope. The phenotype of DCs was detected by flow cytometry. The migration ability of DCs was detected by a transwell experiment. We found that cytosolic dsDNA, 2′3′-cGAMP, cGAS and ISGs expression, and IFN-β in cell supernatant were all increased with the doses of X-ray in the range of 0–16 Gy in normoxic glioma cells. Nevertheless, hypoxia significantly inhibited the radiation-induced dose-dependent activation of cGAS-STING-IFNI pathway. Furthermore, manganese (II) ion (Mn2+) significantly improved cGAS-STING-IFNI pathway activation induced by X-ray in both normoxic and hypoxic glioma cells, thereby promoting the maturation and migration of DCs. The responses of cGAS-STING-IFNI pathway to ionizing radiation were mainly investigated under normoxic condition, but the experiments described here indicated that hypoxia could hinder the pathway activation. However, Mn2+ showed radiosensitizing effects on the pathway under either normoxic or hypoxic conditions demonstrating its potential as a radiosensitizer for glioma through activating an anti-tumor immune response. [ABSTRACT FROM AUTHOR]

The cyclic guanosine monophosphate‐adenosine monophosphate synthase (cGAS)/stimulator of interferon genes (STING) signalling pathway has been a promising target for anticancer immunity, but rationally activating and enhancing this pathway in tumour cells is critical. Herein, a glutathione sensitive ZnFe2O4‐based nanosystem is developed to programmatically initiate and enhance the STING signalling pathway in tumour cells. The prepared ZnFe2O4 nanoparticles were coated with cancer cell membrane (CCM), which enabled the nanosystem target tumour cells. In tumour cells, ZnFe2O4 nanoparticles could be disintegrated by responding to high level glutathione, and the released Fe3+ generated reactive oxygen species to induce the DNA leakage into the cytoplasm to stimulate cGAS. Then Zn2+ promoted cGAS‐DNA phase separation to intensify the cGAS enzymatic activity. In addition, the low dose encapsulation of paclitaxel (PTX) acting as an antimitotic agent (ZnFe2O4‐PTX@CCM) ensured the sustained activation of cGAS/STING pathway. The in vitro and in vivo results confirmed that ZnFe2O4‐PTX@CCM elevated the cGAS/STING activity, promoted dendritic cell maturation, increased cytotoxic T lymphocyte and natural killer cells infiltration, eventually inhibiting the tumour progress and postoperative recurrence. This study provided feasible references on constructing STING activation nanosystem for tumour immunotherapy. [ABSTRACT FROM AUTHOR]

The Oligocene Yacheng Fm contains the most important source rocks that have been confirmed by exploratory wells in the Qiongdongnan Basin. The efficiency of these source rocks is the key to the breakthrough in natural gas exploration in the study area. This paper analyzes the hydrocarbon potential of each sag in this basin from the perspective of control of both source rocks and geothermal heat. Two types of source rocks occur in the Yacheng Fm, namely mudstone of transitional facies and mudstone of neritic facies. Both of them are dominated by a kerogen of type-III, followed by type-II. Their organic matter abundances are controlled by the amount of continental clastic input. The mudstone of transitional facies is commonly higher in organic matter abundance, while that of neritic facies is lower. The coal-measure source rocks of transitional facies were mainly formed in such environments as delta plains, coastal plains and barrier tidal flat-marshes. Due to the control of Cenozoic lithosphere extension and influence of neotectonism, the geothermal gradient, terrestrial heat flow value (HFV) and level of thermal evolution are generally high in deep water. The hot setting not only determines the predominance of gas generation in the deep-water sags, but can promote the shallow-buried source rocks in shallow water into oil window to generate oil. In addition to promoting the hydrocarbon generation of source rocks, the high geothermal and high heat flow value can also speed up the cracking of residual hydrocarbons, thus enhancing hydrocarbon generation efficiency and capacity. According to the theory of joint control of source quality and geothermal heat on hydrocarbon generation, we comprehensively evaluate and rank the exploration potentials of major sags in the Qiongdongnan Basin. These sags are divided into 3 types, of which type-I sags including Yanan, Lingshui, Baodao, Ledong and Huaguang are the highest in hydrocarbon exploration potential.

Heterostructures can not only maintain/avoid the desired characteristics/defects of their monolayers, but also have synergistic effects due to the contribution of an internal electric field from the heterostructure interlayer. Hexagonal boron phosphide (h-BP) and V2CS2 were constructed into heterostructure (h-BP/V2CS2) and homogeneous bilayers (Dh-BP and DV2CS2), which were studied comparatively for their storage performances as anodes for metal (Li/Na/Mg/Ca)-ion batteries (LIBs/NIBs/MIBs/CIBs) using first-principles. The h-BP/V2CS2 can adsorb five layers of Mg atoms while Dh-BP cannot adsorb any Mg atoms; heterostructures with a maximum adsorption concentration are stable at room temperature, while Dh-BP structures are unstable in the same cases, which make Dh-BP unsuitable as LIB/NIB/MIB/CIB anodes. h-BP/V2CS2 completely exceeds DV2CS2 in capacity, average OCV or interlayer barrier for LIBs/NIBs/MIBs/CIBs owing to its stronger internal electric field. In particular, for MIBs/NIBs, the capacity of heterostructure is 1219/732 mA h g−1, which is much higher than the 753/226 mA h g−1 of DV2CS2; the average OCV of heterostructure is 0.07/0.35 V, as low as half of that of DV2CS2. The excellent storage performance of the heterostructure in NIBs/MIBs makes it very worthy of attention due to the urgent need for NIBs/MIBs with high energy density. [ABSTRACT FROM AUTHOR]

The dynamic stability of long combination vehicles (LCVs) is an important part of vehicle safety. An LCV, its driver and the road constitute a unique closed-loop dynamic system. Assessing the dynamic stability is difficult due to the complex interactions of driver-tractor-trailers-road. Rearward amplification (RA) is an effective performance measure of the dynamic stability; various methods are applied for evaluating the RA. However, the measures from different methods may differ significantly. What are the root causes for the disparity of evaluation results? This paper tackles the problem by investigating the typical methods for evaluating the measure of two LCVs, i.e. an A-train double and a B-train double. To this end, simulations of the LCVs are conducted using TruckSim software. The study discloses the main causes for the disparity of the measures from different methods, and recommends the effective approaches to the assessment of the RA. [ABSTRACT FROM AUTHOR]

Car–trailer combinations can experience unstable motion modes such as trailer-sway, jackknifing and rollover that can lead to fatal accidents. These unstable motions can be mitigated with the use of an active trailer steering (ATS) system. Prior studies in ATS have leveraged the linear quadratic regulator (LQR) as an ATS controller but for many of these designs it was assumed that the vehicle and operating parameters were constant. In reality, vehicle and operating parameters may vary and have an impact on the stability of a car–trailer combination. In this paper, the weighting matrices of the LQR controller are determined using the GDE3 evolutionary optimization algorithm with the objective of addressing the design trade off between minimizing the car–trailer's path-following performance for low vehicle speeds and minimizing the rearward amplification for high vehicle speeds. The effectiveness of the approach is demonstrated using a numerical simulation car–trailer model developed in the CarSim simulator. Our results show that the multi-objective tuned gain scheduling controller outperforms a non-tuned gain scheduling controller in terms of improving the lateral stability and the path following performance of car–trailer combinations in driver in the loop single lane-change maneuvers at a constant vehicle forward speed. [ABSTRACT FROM AUTHOR]