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Background Antibody-drug conjugates (ADCs) have been the preferred regimens for human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC) after trastuzumab. Unfortunately, there is little data showing which ADCs should be chosen for those patients whose treatment with tyrosine kinase inhibitors (TKIs) failed. This study aims to analyze the efficacy and safety between novel anti-HER2 ADCs and trastuzumab emtansine (T-DM1) for those with TKIs failure. Materials and methods HER2-positive MBC using ADCs from January 2013 to June 2022 were included, and all of them were treated with TKIs. The primary study endpoint was progression-free survival (PFS), and the secondary study endpoints were objective response rate (ORR), clinical benefit rate (CBR), and safety. Results A total of 144 patients with 73 patients in the novel anti-HER2 ADCs group and 71 patients in the T-DM1 group. In these novel ADCs, 30 patients received trastuzumab deruxtecan (T-Dxd), 43 patients receive other novel ADCs. The median PFS in the novel ADCs group and T-DM1 group were 7.0 months versus 4.0 months, respectively, and ORR was 54.8% versus 22.5%, CBR was 65.8% versus 47.9%, respectively. In subgroups analysis, the PFS were both significantly improved in patients receiving T-Dxd and other novel ADCs compared with T-DM1. The most common grades 3-4 adverse events in the novel anti-HER-2 ADCs group were neutropenia (20.5%) and thrombocytopenia (28.1%) in the T-DM1 group. Conclusions In patients with HER2-positive MBC previously treated with TKIs, both T-Dxd and other novel anti-HER2 ADCs yielded statistically significant better PFS than T-DM1 did, with tolerable toxicities.

Purpose: we used the real-world data of Chinese patients to describe clinicopathological characteristics of patients with breast cancer brain metastases (BCBM) and to investigate survival after diagnosis of brain metastases (BM). Methods: The clinicopathological characteristics of 700 patients with BCBM at the fifth Medical Center of Chinese PLA General Hospital between 2003 and 2021 were retrospectively reviewed. Information was collected from the electronic medical records, including patient demographics, tumor characteristics, and dates of diagnosis of original breast carcinoma and subsequent metastases. Sites and number of metastatic lesions were also recorded, along with data on treatments and outcomes. The prognostic and predictive effects of these clinicopathological variables in BCBM were analyzed. Results: The median age at diagnosis of primary breast cancer was 44 years (range, 22-80 years) and all patients were female. Among the 700 patients with BCBM, 30.0%, 49.7%, 18.9%, 1.4% had Luminal, HER2 positive, triple-negative and unknown subtypes, respectively. Based on available clinical information, the proportions of extracranial metastasis at diagnosis included bone (63.7%), lymph nodes (61.6%), lung (55.1%), liver (50.1%), the soft tissues of the thoracic wall (26.1%) and bone marrow (4.9%).The median time from the diagnosis of breast cancer to the development of BM was 52.0 months [95% confidence interval (CI), 44.3-59.7], 36.0 months (95%CI, 31.9-40.1), and 29.0 months (95%CI, 22.4-35.6) for patients with Luminal, HER2 positive and triple-negative, respectively (p Table 1.patient characteristics (n=700)Parametern (%)Mean age, y, at diagnosis (range)44(22-80)Stage at initial diagnosis of cancerI89(12.7)II342(48.9)III167(23.9)IV69(9.9)unknown33(4.7)Molecular subtypesLuminal A/B211(30.0)HER2-positive347(49.7)TNBC132(18.9)Unknown10(1.4)Site of first metastasisBrain128(18.3)Others572(81.7)Number of BM at time of BM diagnosis1189(27.0)248(6.9)≥3454(64.9)Unknown9(1.3)Visceral metastases at diagnosis of BMliver351(50.1)lung386(55.1)bone446(63.7)lymph nodes431(61.6)the soft tissues of the thoracic wall183(26.1)bone marrow34(4.9) Citation Format: Tao Wang, Huiqiang Zhang, Feng Li, Xia Wu, Jinmei Zhou, Shao hua Zhang, Li Bian, Ze fei Jiang. The real word study on clinical features and prognostic factors of Chinese breast cancer patients with brain metastasis [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-21-04.

To investigate the relationship between serum lipid level and cognitive function in middle-aged and elderly patients with type 2 diabetes mellitus(T2 DM).A cross-sectional study was implemented in 2017 to explore the correlation between lipid level and cognitive function in middle-aged and elderly diabetic patients. A random sample of 1526 middle-aged and elderly people were recruited from 2 communities in Beijing. Fasting blood samples were collected for blood lipid level detection, and the cognitive function of the subjects was assessed by the Montreal Cognitive Assessment Scale(MoCA). Logistic regression model was used to analyze the correlation between serum lipid levels and mild cognitive impairment(MCI) in elderly and T2 DM patients and control group.Compared with the control group, there were significant differences in blood lipid levels in T2 DM group. The levels of total cholesterol(TC) and high density lipoprotein cholesterol(HDL-C) in T2 DM group were lower than those in the control group, while triglyceride(TG) and low density lipoprotein cholesterol(LDL-C) were higher than those in the control group. Logistic regression analysis showed that high level of TC was a risk factor for MCI in patients with T2 DM, while high level of LDL-C was a protective factor, but no association was observed in the control population.Phenotype of T2 DM may affect the relationship between lipid level and cognitive function in middle-aged and elderly people.

With the continuous exploitation of coal resources, human safety has been seriously threatened during the mining process. Therefore, it is of great significance to establish an efficient human infrared image recognition system. In this paper, three classes of infrared image data of the human body are collected by a thermal imager, namely Human, Human others and None. According to the characteristics of downhole infrared images, a distributed channel feature extraction module (DCFE) is designed, and DCA-Net is proposed based on this module. The experimental results show that the recognition rate of the network reaches 98%. Compared with other networks, this network has better recognition performance. Among them, the recognition rate of DCA-Net50 reaches 98.214%, the amount of parameters and calculations are relatively small, and the cost-effectiveness is the highest. It is suitable for the human body infrared image recognition system that requires high accuracy and high real-time performance.

At present, local therapy, such as surgery and radiotherapy, is the mainstay treatment for brain metastasis and anti-human epidermal growth factor receptor type 2 (HER2)-targeted therapy has been shown to be efficacious for HER2This retrospective, observational study collected data from 79 HER2The intracranial ORRs were 48.6% in Group A and 20.5% (9/44) in Group B (P=0.015). The intracranial CBRs were 80.0% in Group A and 65.9% in Group B. The median intracranial PFS times (IC-PFS) were 15.0 months and 9.0 months in Group A and Group B, respectively (P=0.385). There was no statistically significant difference in OS between the 2 groups (95.0Pyrotinib combined with radiotherapy is recommended for HER2

CDK4/6 inhibitors combined with endocrine therapy are standard first- or second-line treatment for patients with HR-positive and HER2-negative advanced breast cancer, however, there is currently no optimal recommendation for therapeutic strategies after progression on CDK4/6i. The aim of this study is to analyze the efficacy and safety of HDAC inhibitor Tucidinostat combined with endocrine therapy in patients after prior CDK4/6 inhibitor progression.The pathological and clinical data of 44 HR-positive and HER2-negative breast cancer patients treated with tucidinostat after progression on CDK4/6i at the Breast Oncology Department of the Fifth Medical Center of the PLA General Hospital from July 2019 to October 2021 were retrospectively analyzed. Observation indexes included progression-free survival (PFS), overall survival (OS), clinical benefit rate (CBR), objective response rate (ORR) and adverse events. At the same time, we attempted to identify potential genomic predictors using available next-generation sequencing (NGS).A total of 44 patients were enrolled in this study. Median follow-up was 10 months (1-26 months) by the data cutoff date (February 2022). The CBR was 6.8% (3/44), the median PFS was 2.0 months (95% CI 1.9-2.1), and the median OS was 14 months (95% CI 6.3-21.7). The mPFS was 4.1 months (95%CI: 0-8.2) in patients with 1 metastatic site, and the mPFS was 4.5 months (95%CI: 4.2-4.8) in patients who received sequential tucidinostat after CDK4/6i failure. Multivariate analysis showed that patients with 1 metastatic site or sequential tucidinostat treatment after failure of CDK4/6i were more likely to benefit from tucidinostat combined with endocrine therapy. Preliminary data showed PIK3CA mutation may be associated with resistance of tucidinostat therapy. No grade 4 adverse events and no treatment-related deaths were recorded in the study. Dose reductions because of adverse events occurred in 4 (9.1%) patients.This study preliminarily shows that tucidinostat combined with endocrine therapy may be an optional sequential strategy for patients with HR+/HER2-advanced breast cancer that has progressed on CDK4/6 inhibitor, especially for these with lower tumor burden and fewer prior palliative treatment.

The combustion of combustible gaseous mixture with/without oil droplet is studied based on a rapid compression machine under conditions comparable with the state at the end of compression in SI-eng...

BackgroundNeoadjuvant therapy is a standard treatment for patients with large, nonmetastatic breast cancer and may allow breast-conserving surgery after tumor downsizing while decreasing the risk of subsequent relapse. Dynamic changes of circulation tumor cells (CTCs) have a role in predicting treatment efficacy of breast cancer. However, the relationship between CTC enumeration before neoadjuvant therapy and pathologic complete response rate is still uncertain.MethodsThe study was exploratory. A total of 50 breast cancer patients were enrolled in a phase II clinical study of neoadjuvant therapy for HER-2-positive early breast cancer. They were enrolled for blood draws before and after neoadjuvant therapy. We used two methods (CellSearch and TUMORFISH) to detect CTCs. We compared the sensitivity of the two systems and investigated the correlation of the enumeration on baseline CTCs with the diagnosis, prognosis, and efficacy of neoadjuvant therapy of the patients with HER-2-positive early breast cancer. We also explored the dynamic change of CTCs after neoadjuvant therapy.ResultsThe sensitivity of TUMORFISHER (27/50) method was significantly higher than that of the CellSearch system (15/50, p=0.008). The CTC numbers detected by the two detection systems were not significantly correlated with lymph node status, clinical stage, ki-67 level and hormone receptor status. Patients with ≥1 CTC before neoadjuvant therapy measured by the TUMORFISHER system had a significant high pCR rate (74.1% vs. 39.1%, p = 0.013); whereas, there was no predictive effect on pCR by CellSearch system (73.3% vs. 51.4%, p = 0.15). Patients with a decrease in CTCs enumeration after neoadjuvant therapy were more likely to achieve pCR than those with no change or increase in CTCs enumeration (87.5% vs 50.0%, p = 0.015) by the TUMORFISHER method. Unfortunately, there was no predictive value of CTCs enumeration for EFS before and after neoadjuvant therapy by two methods.ConclusionsOur study demonstrates that the new CTCs detection method TUMORFISHER system has a higher checkout rate in early breast cancer than the CellSearch system, and shows the opportunity of CTC enumeration as a novel assistant biomarker to predict the response of neoadjuvant therapy in patients with HER-2-positive early breast cancer.

Background: Neoadjuvant therapy is a standard treatment for patients with large, nonmetastatic breast cancer and may allow breast-conserving surgery after tumor downsizing while decreasing the risk of subsequent relapse. Dynamic changes of circulation tumor cells (CTCs) have a role in predicting treatment efficacy of breast cancer. However, the relationship between CTC enumeration before neoadjuvant therapy and pathologic complete response rate is still uncertain.Methods: The study was exploratory. A total of 50 breast cancer patients were enrolled in a phase II clinical study of neoadjuvant therapy for HER-2-positive early breast cancer. They were enrolled for blood draws before and after neoadjuvant therapy. We used two methods (CellSearch and Tumor-Fisher) to detect tumor cells in bloodstream. We compared the sensitivity of the two CTC detection systems and investigated the correlation of the enumeration on baseline CTCs with the diagnosis, the prognosis, and the efficacy of the neoadjuvant therapy of the patients with HER-2-positive early breast cancer. We also explored the dynamic change of CTCs after the neoadjuvant therapy in enrolled patients. Results: The sensitivity of CTCs detection by the Tumor-Fisher (27/50) method was significantly higher than that of the CellSearch system (15/50, p=0.008). The CTC levels detected by the two detection systems were not significantly correlated with lymph node status, clinical stage, ki-67 level and hormone receptor status. Patients with ≥1 CTC before neoadjuvant therapy measured by the Tumor-Fisher system had a significant high pCR rate (74.1% vs. 39.1%, p = 0.013); However, CTC levels detected by the CellSearch system did not show a predictive value for pCR (73.3% vs. 51.4%, P = 0.15). Patients with a decrease in CTCs enumeration after neoadjuvant therapy were more likely to achieve pCR than those with no change or increase in CTCs enumeration (87.5% vs 50.0%, P = 0.015) by the Tumor-Fisher method, whereas no predictive effect on pCR by CellSearch system. Unfortunately, there was no predictive value of CTC enumeration for EFS before and after neoadjuvant therapy by two methods. Conclusions: Our study demonstrates that the new CTC detection method Tumor-Fisher system has a higher CTC detection rate in early breast cancer than the CellSearch system, and shows the opportunity of CTC enumeration as a novel assistant biomarker to predict the response of neoadjuvant therapy in patients with HER-2-positive early breast cancer.

In the increasingly complex electromagnetic environment of modern battlefields, how to quickly and accurately identify radar signals is a hotspot in the field of electronic countermeasures. In this paper, USRP N210, USRP-LW N210, and other general software radio peripherals are used to simulate the transmitting and receiving process of radar signals, and a total of 8 radar signals, namely, Barker, Frank, chaotic, P1, P2, P3, P4, and OFDM, are produced. The signal obtains time-frequency images (TFIs) through the Choi–Williams distribution function (CWD). According to the characteristics of the radar signal TFI, a global feature balance extraction module (GFBE) is designed. Then, a new IIF-Net convolutional neural network with fewer network parameters and less computation cost has been proposed. The signal-to-noise ratio (SNR) range is −10 to 6 dB in the experiments. The experiments show that when the SNR is higher than −2 dB, the signal recognition rate of IIF-Net is as high as 99.74%, and the signal recognition accuracy is still 92.36% when the SNR is −10 dB. Compared with other methods, IIF-Net has higher recognition rate and better robustness under low SNR.

Acoustic characteristics of a thrust chamber with quarter-wave resonators are numerically studied based on the unsteady Reynolds-averaged Navier-Stokes (URANS) method. Organized pressure disturbance model and constant-volume bomb model are applied as artificial disturbances to excite pressure oscillations in the chamber. Eigenfrequencies and amplitudes of acoustic modes of the chamber are obtained by fast fourier transform (FFT) analysis, while damping characteristics are evaluated by the half-power bandwidth method. Predicted damping capacities of the chamber with and without quarter-wave resonators agree well with experimental results. Pressure oscillations can be controlled by a quarter-wave resonator mainly through reducing the amplitude of target acoustic mode, rather than increasing damping capacity of the chamber. Major damping mechanism of the resonator is cutting down pressure peak of target acoustic mode and raising up its pressure trough (CPRT); therefore the amplitude of target acoustic mode is reduced significantly. Moreover, acoustic energy can be dissipated by vortex at the orifice and by viscosity on the surface of a resonator, which increase damping capacity of the chamber slightly. Under the condition with multi-modes pressure oscillations, a resonator can still suppress pressure oscillations of target acoustic mode through CPRT. However, it may enhance pressure oscillations of other modes due to redistribution of oscillation energy among all acoustic modes.

The potential advantages of rotating detonation combustion are gradually approved, and it is becoming a stable and controllable energy conversion way adopted to the propulsion devices or ground-engines. This study focuses on the rotating detonation-based turboshaft engine, and the architecture is presented for this form of engine with compatibility between the turbomachinery and rotating detonation combustor being realized. The parametric performance simulation model for the rotating detonation-based turboshaft engine are developed. Further, the potential performance benefits as well as their generation mechanism are revealed, based on the comprehensive performance analysis of the rotating detonation-based turboshaft engine. Comparisons between the rotating detonation turboshaft engine and the conventional one reveal that the former holds significant improvements in specific power, thermal efficiency, and specific fuel consumption at lower compressor pressure ratios, and these improvements decrease with the increase of compressor pressure ratio and increase as turbine inlet temperature increases. The critical compressor pressure ratio corresponding to the disappearance of specific power improvement is higher than that corresponding to the disappearance of thermal efficiency and specific fuel consumption. These critical compressor pressure ratios are positively correlated with flight altitude and negatively correlated with flight velocity. The conductive research conclusion is guidable for the design and engineering application of rotating detonation-based engines.

An efficient and reliable flight Mach controller is specially needed for an aircraft. A Flight mach fuzzy controller based on modern fuzzy control theory is designed for an unmanned aerial vehicle (UAV) using a turbojet engine. The theory and process of designing control law are introduced and its control performance is optimized by changing the scale factors. In order to evaluate the control performance, a mathematical simulation system and a hardware-in-the-loop (HIL) simulation platform are built. The mathematical simulation and HIL simulation are carried out respectively, and the simulation results are compared. The evaluation shows good control performance to stabilize the UAV flight Mach number to the target one quickly by controlling the engine work condition.

In this paper, a dual-loop active disturbance rejection attitude controller design method is proposed for the attitude control of aircraft. Firstly, based on the nonlinear dynamic model of aircraft, the control system model with inner loop as angular velocity and outer loop as attitude angle is established. Secondly, the extended state observer for the inner loop is established to estimate and compensate the state of the system in real time. The controller of the compensated series integral system is designed by using the linear PD control method. Thirdly, the extended state observer and controller for the outer loop are designed by the same method. Finally, the stability proof of the dual-loop attitude control method is given based on the Lyapunov theorem of stability. Simulation results show that compared with the traditional PID attitude control method, the dual-loop ADRC attitude control method has better control quality in tracking speed, tracking error, and system anti-interference ability. The control parameters to be adjusted in this method have distinct physical significance. So this method has a wide range of engineering application prospects.

In this paper, an extended state observer (ESO) is established for the linear model of aircraft with small disturbance, considering wind disturbance, structural disturbance, model uncertainty and measurement noise. The real-time estimation and compensation of the system state are carried out. The nonlinear feedback control law is designed to complete the design of aircraft attitude controller. The simulation results show that the attitude controller with extended state observer and nonlinear control law has better control quality than the traditional attitude control correction network method. In the case of large unknown measurement noise, the system has better filtering characteristics and robustness.

A configuration for a dual-duct rotating detonation aero-turbine engine (DRDATE) is proposed. With the isolator and mixer arranged upstream and downstream from the rotating detonation combustor (RDC) respectively, the compatibility between turbomachinery and RDC can be realized. The conventional single annular RDC is replaced with a multi-annular RDC to expand the stable operation range of the RDC. A low-order analytical model of the rotating detonation process is presented, and comparisons between the results calculated by this model and the CFD solvers show reasonable agreement. Thereafter, a performance simulation model of the DRDATE is established, and further the variations in the overall performances with design parameters under three different flight conditions are investigated. The results demonstrate that, there exists an optimum compressor pressure ratio π opt that maximizes the specific thrust and an optimum pressure ratio π opt ′ that maximizes the thermal efficiency for the DRDATE. With an increase in the compressor and turbine polytropic efficiency and turbine inlet temperature, both π opt and π opt ′ increase monotonically. Comparisons between the DRDATE and conventional turbine engine reveal that, the former exhibits a major improvement in overall performance at low compressor pressure ratios, while the improvement decreases continuously with an increase in the pressure ratio. Moreover, as the turbine inlet temperature increases, the specific thrust improvement increases and the fuel consumption performance improvement decreases monotonically.

In this research, n-hexane flashing jets discharged from two-hole GDI injectors were studied numerically with different superheat levels and inter-hole angles. The mutual interaction between under-expanded flashing jets was discussed in terms of its effect and mechanism. It was found that under certain conditions, the jets deflected towards each other and merged into one jet which moved along the central axis, indicating the occurrence of spray collapse. The spray collapse is ascribed to the pressure drop in the central area between the two jets, which is an effect of the low-pressure cores within individual jets. The pressure drop in the central area is mainly determined by two effects, i.e. the intensity and volume of the low-pressure cores in individual jets, and the formation of the secondary cell which protects the central area from being affected by the ambience. In the transitional stage from non-collapse to fully-collapse, the pressure drop was enhanced with the rise of superheat level or the decrease of inter-hole angle, and the extent of spray collapse increased. Besides, unique shock structures similar to those of under-expanded gaseous twin-jets were formed at high superheat levels, which consist of two primary cells and a secondary cell.

Photoelectrocatalysis (PEC) produces high-efficiency electron-hole separation by applying a bias voltage between semiconductor-based electrodes to achieve high photocatalytic reaction rates. However, using PEC to treat polluted gas in a gas-phase reaction is difficult because of the lack of a conductive medium. Herein, we report an efficient PEC system to oxidize NO gas by using parallel photoactive composites (TiO

Nitrous oxide fuel blend propellants have great potential to be used in rocket engine, and investigations on the fundamental combustion characteristics of such propellants are therefore necessary to control flashback and develop their chemical kinetics mechanism. Laminar burning velocities (LBVs) of C2H4/N2O flames are measured by using spherical expansion flames in this paper at 0.5–2.0 atm and 280 K. The present method for upper and lower limits of effective flame radius is reasonable for the experimental stretched flame speeds can be fitted very well with the flame stretch rates. The LBVs of C2H4/N2O flames are smaller than those of C2H4/N2/O2 flames (same N/O ratio as N2O) at conditions near stoichiometric ratio, while they are larger than those at other conditions especially at fuel-rich side. The LBVs of C2H4/N2O flames are not sensitive to the pressure in the measured range. Two kinds of sub-mechanisms are applied for detailed chemical kinetics mechanisms of C2H4/N2O reactions, which are USC Mech II-2 for hydrocarbon reactions as well as GRI 3.0 mechanism and San Diego mechanism for nitrogen oxide reactions respectively. Eight key elementary reactions are chosen based on the sensitivity analysis, and the effects of their available rate constants from literatures on the LBVs are tested. Modified mechanisms for C2H4/N2O reactions are therefore proposed by replacing the rate constants of these key elementary reactions, which predicts well for LBVs of hydrocarbon/N2O flames. Sensitivity analyses are performed for C2H4/N2O flames at different equivalence ratios, it is found that the N2O decomposition is a dominant reaction in conditions near stoichiometric ratio, while it is the codominant and nondominant reaction in fuel-lean and fuel-rich conditions respectively. Furthermore, the reaction pathways of oxidizers consumption in C2H4/N2O flames and C2H4/N2/O2 flames are analyzed, and the observations on the LBVs of these two flames in the experiment can be well explained through the reaction pathways and their relative changes under fuel-lean, stoichiometric and fuel-rich conditions.

Pulsating instabilities in hydrogen/air double-flame partially premixed counterflow flames are numerically investigated with detailed chemistry and transport. The whole stability map on the equivalence ratio-strain rate plane is obtained. With the increase of the equivalence ratio or strain rate, there are two transitions for combustion patterns from stable to unstable, and to stable again. For the one transition presented at the smaller equivalence ratio and strain rate, it is similar to that in the pure premixed flame. After this transition, the flames do not extinguish with the increase of equivalence ratio or strain rate, but transit from unstable to stable. For the second transition appeared at the larger equivalence ratio and strain rate, the effects of equivalence ratio and strain rate on the pulsating instability are completely contrary to those in pure premixed flames. The effective activation energy of the premixed flame of partially premixed flame predicted by a new method is applied to calculate the Zeldovich number. Then the first transition is proved to satisfy Sivashinsky-like criterion, but the critical value is larger than that for pure premixed flame due to the heat transfer between premixed and non-premixed flames. It means that the pulsating instability is more difficult to happen in partially premixed flames. From the first transition to the second transition along the equivalence ratio or strain rate, though the premixed flame becomes weaker, the increase degree of heat transfer from non-premixed flame to premixed flame is much larger than the decrease degree of max heat release of the premixed flame due to decrease of distance and increase of temperature difference of two flames, which induces the premixed flame stable again. The second transition is therefore controlled by the heat transfer between two flames.

In this paper, n-hexane flashing jets discharged from a single-hole gasoline direct injector (GDI) were studied numerically with the adoption of diffuse Eulerian framework and the homogeneous relaxation model (HRM). The fuel temperature ranged from 30 to 130 °C, and the ambient pressure varied from 20 to 101 kPa. The results showed that considerable vaporization started at the counter bore and a liquid core existed near the nozzle exit. Due to drastic vaporization, the pressure within the liquid core increased so the two-phase flow became under-expanded. Violent expansion then occurred and a low-pressure region was formed, which is believed as the origin of the spray collapse under flashing conditions for multi-hole GDI injectors. At high superheat levels, shock wave structures similar to those in highly under-expanded gaseous jets were identified. However, the transonic position located at some distances from the nozzle rather than at the throttle. Besides, vapor fraction played the dominant role in the onset of expansion, while the expansion was ended by the pressure difference between the two sides of the Mach disk.

A lower combustor inlet Mach number is desirable in order to design a compact, lightweight combustor and boost the overall performance of the scramjet engine. In this study, a thrust control strategy is proposed for a hydrogen-fueled scramjet taking into account the operating limitations, which is called the minimum combustor inlet Mach number rule since the combustor inlet Mach number is used as the control variable. By scheduling the fuel supply and modifying the intake geometry, the combustor inlet Mach number can be minimized while ensuring a certain thrust output within the operation constraints. In this manner, the scramjet engine can be operated with high specific thrust and low fuel consumption throughout the flight envelope. The thrust control strategy is further applied to a hydrogen-fueled scramjet in the hypersonic flight regime. Because the combustor inlet Mach number varies with flight conditions, the thrust strategy can be applied in practice by monitoring the following aerothermodynamic parameters in different flight regimes instead: (1) combustor outlet Mach number, (2) combustor inlet static temperature, and (3) combustor outlet static temperature. Furthermore, the effects of the thrust output on the division of flight regime are investigated, and the overall performance of the hydrogen-fueled scramjet engine obtained from applying the thrust control strategy is discussed in detail.

The present study was designed to explore the neuroprotective effects of docosahexaenoic acid (DHA) and/or vitamin E (VE) in vitro. The PC12 cells were pretreated with DHA and/or VE for 4 h, followed by 50 μmol L-1 Aβ25-35 treatments for another 48 h. The cells were then collected and used for the measurements of oxidative stress parameters. Real time-PCR and western blot were applied to measure fatty acid transporters, Nrf2 and its downstream antioxidant targets' gene and protein expression. Our results indicated that the Aβ25-35 treatment inhibited cellular growth, increased intracellular ROS generation and decreased the mitochondrial membrane potential. The Aβ25-35 treatment decreased the total antioxidant capacity (T-AOC), whereas it increased the MDA levels in neuron cells. Pretreatment of cells with VE or DHA could antagonize the Aβ25-35-mediated cell growth inhibition and mitochondrial membrane potential decline. Activation of the Nrf2 signaling pathway and regulation of CD36, SRB1 and FABP5 expression were observed in DHA- and DHA + VE-pretreated cells. Our results indicated a synergistic effect of DHA and VE in antagonizing the oxidative damage caused by Aβ25-35 in the PC12 cells. The results of the present study will shed light on the application of nutritional intervention for DHA and VE in preventing neuronal damage-related diseases.

In the field of electronic countermeasure, the recognition of radar signals is extremely important. This paper uses GNU Radio and Universal Software Radio Peripherals to generate 10 classes of close-to-real multipulse radar signals, namely, Barker, Chaotic, EQFM, Frank, FSK, LFM, LOFM, OFDM, P1, and P2. In order to obtain the time-frequency image (TFI) of the multipulse radar signal, the signal is Choi–Williams distribution (CWD) transformed. Aiming at the features of the multipulse radar signal TFI, we designed a distinguishing feature fusion extraction module (DFFE) and proposed a new HRF-Net deep learning model based on this module. The model has relatively few parameters and calculations. The experiments were carried out at the signal-to-noise ratio (SNR) of −14 ∼ 4 dB. In the case of −6 dB, the recognition result of HRF-Net reached 99.583% and the recognition result of the network still reached 97.500% under −14 dB. Compared with other methods, HRF-Nets have relatively better generalization and robustness.

The performance analysis of mixed-exhaust turbofan engine with multi-annular rotating detonation duct burner (RDDB) is conducted for the first time, considering that the flow path of the bypass duct is ideal for a rotating detonation combustor (RDC). The configuration of the multi-annular rotating detonation combustor is constructed aiming at the advantages of a wider operation range and uniform outlet parameters over the single-annular one. Then, a parametric analysis model of the mixed-exhaust turbofan engine with a rotating detonation duct burner is developed. Thereafter, the effects of duct burner parameters on the engine performance and operating characteristics are investigated. The mixed-exhaust turbofan engine with a rotating detonation duct burner shows superior overall performance to that of one with an isobaric afterburner (ICAB) over a wide operation range. The separate-exhaust rotating detonation duct burner can hold characteristics that are higher than those of the mixed-exhaust one at lower values of fan pressure ratio, while the mixed-exhaust one corresponds to lower values of turbine inlet temperature. When the rotating detonation duct burner is “on,” the low-pressure rotor operating line moves toward the surge line on the low corrected shaft speed side but away from the surge line on the high corrected shaft speed side.

We demonstrate the quantum-enhanced supervised classification of vectors in a nitrogen-vacancy ($NV$)--center system using the algorithm of Lloyd, Mohseni, and Rebentrost (arXiv:1307.0411). A $^{13}\mathrm{C}$ nuclear spin is employed to encode the vectors with the spin-triplet state of the $NV$ center as an ancilla. We design efficient methods to prepare the initial electron-nuclear entangled state within the coherence time ${T}_{2}^{*}$ of the electron spin, and then compute the distance between the test vector and the center of each class by measuring the level population through maximum likelihood estimation. Our experiment allows more than one reference vector in each class, thus forming an important enabling step toward quantum-enhanced machine learning.

Combustion instabilities in a small MMH/NTO liquid rocket engine used for satellite attitude and course control are numerically investigated. A three-dimensional Navier-Stokes code is developed to simulate two-phase spray combustion for cases with five different droplet Sauter Mean Diameters. As the droplet size increases from 30 microns to 80 microns, pressure oscillations are stronger with larger amplitudes. But an increase of the droplet size in the range of 80 microns to 140 microns indicates a reduction in the amplitudes of pressure oscillations. This trend is the same as the Hewitt criterion. The first tangential (1T) mode and the first longitudinal (1L) mode self-excited combustion instabilities are captured in the 60-micron and 80-micron cases. Abrupt spikes occur in the mass fraction of MMH and coincide with abrupt spikes in the mass fraction of NTO at the downstream regions just adjacent to the impinging points. Thus, local combustible high-dense mixtures are formed, which result in quasiconstant volume combustion and abrupt pressure spikes. The propagation and reflection of pressure waves in the chamber stimulate the combustion instability. When the droplet size is too small or too large, it is difficult to form local high-dense premixtures and combustion is stable in the chamber.

Based on the URANS equation, a numerical simulation is carried out for acoustic properties of the thruster chamber with coaxial injectors and plenum chamber in a liquid rocket engine. Pressure oscillations with multiacoustic modes are successfully excited in the chamber by using the constant volume bomb method. FFT analysis is applied to obtain the acoustic properties of eigenfrequencies, power amplitudes, and damping rates for each excited acoustic mode. Compared with the acoustic properties in the model chamber with and without an injector as well as with and without the plenum chamber, it can be found that the injector with one open end and one half-open end still can work as a quarter-wave resonator. The power amplitudes of the acoustic mode can be suppressed significantly when its eigenfrequency is close to the tuning frequency of the injector, which is achieved by Cutting down the pressure Peak and Raising up the pressure Trough (CPRT). Compared with the acoustic properties in the model chamber with and without the plenum chamber, it can be found that 1L acoustic pressure oscillation is inhibited completely by the plenum chamber and other acoustic pressure oscillations are also suppressed in a different extent. The injector and plenum chamber have a little effect on the eigenfrequencies and damping rate of each acoustic mode. For multimode pressure oscillation, it is better for tuning frequency of the injector closing to the lower eigenfrequency acoustic mode, which will be effective for suppression of these multiacoustic modes simultaneously.

An experimental investigation on the ignition of a single lubricating oil droplet in combustible ambient gaseous mixture was performed on a rapid compression machine, under high-temperature...

In order to numerically evaluate the acoustic characteristics of liquid rocket engine thrust chambers by means of a computational fluid dynamics method, a mathematical model of an artificial constant-volume bomb is proposed in this paper. A localized pressure pulse with a very high amplitude can be imposed on specified regions in a combustion chamber, the numerical procedure of which is described. Pressure oscillations actuated by the released constant-volume bomb can then be analyzed via Fast Fourier Transformation (FFT), and their modes can be identified according to the theoretical acoustic eigenfrequencies of the thrust chamber. The damping performances of the corresponding acoustic modes are evaluated by the half-power bandwidth method. The predicted acoustic characteristics and their damping for a special engine combustor agree well with the experimental data, validating the mathematical model and its numerical procedures. A small-thrust liquid rocket engine chamber is then analyzed by the present model. The First Longitudinal (1L) acoustic mode can be excited easily and is hard to be damped. The axial position of the central constant-volume bomb has little influence on the amplitude and damping capacity of the First Radial (1R) and 1L acoustic modes. Tangential acoustic modes can only be triggered by an off-centered constant-volume bomb, among which the First Tangential (1T) mode is the strongest and regarded as the most harmful one. The amplitude of the 1L acoustic mode is smaller, but its damping factor is larger, as a constant-volume bomb is imposed approaching the injector face. These results are contributed to evaluate the acoustic characteristics and their damping of the combustion chamber. Keywords: Acoustic mode, Constant-volume bomb, Damping characteristics, Damping factor, Half-power bandwidth, Pressure oscillation

The successful application of hierarchically porous structure in environmental treatment has provided new insights for solving environmental problems. Hierarchically structured semiconductor materials were considered as promising photocatalysts for NO oxidation in gas phase. Multi-shelled ZnO microspheres (MMSZ) were controllably shaped with hierarchically porous structures via a facile hydrothermal route using amino acid (N-Acetyl- d -Proline) as template and post-calcination treatment. Symmetric Ostwald ripening was used to explain the morphological evolution of hierarchical nanostructure. MMSZ was proved highly efficient for oxidizing NO (400 ppb) in gas phase under UV light irradiation with a much higher photocatalytic removal rate (77.3%) than that of the as-obtained ZnO crystals with other hierachically porous structures, owing to its higher photocurrent intensity. Such greatly enhanced photocatalytic activity can be assigned to the enhanced crystallinity of ZnO, mesopores and unique multi-shelled structure. Enhanced crystallinity promotes photogenerated charges under light irradiation. Mesoporous porosity can ensure enough light scattering between the shells. Multi-shelled structure endows ZnO with higher specific surface area and high frequency of multiple light reflection, resulting in more exposed active sites, higher light utilization efficiency, and fast separation efficiency of photogenerated charge carriers. The experimental results demonstrated that the photogenerated holes (h+) are the main active species. Hierarchically structured ZnO is not only contributed to directly use solar energy to solving various problems caused by atmospheric pollution, but also has potential applications in energy converse and storage including solar cells, lithium batteries, water-splitting, etc.

A configuration is presented for the rotating detonative airbreathing combined cycle engine with compatibility between the turbomachinery and rotating detonation combustor being realized. Two propulsion units are merged to achieve three different operating modes, which provides a favorable propulsion choice for advanced full range and trans-aerosphere vehicles. For the vehicle taking off from the ground, the engine operates at turbojet mode until the thrust demand could not be satisfied. Then the ramjet unit ignites and the operating mode turns into transition mode, during which the ratio of the thrust generated by ramjet unit to the total thrust increases with an increase in M a 0 . When the ratio reaches 1.0, the engine transforms into the ramjet mode. Thereafter, a mode transition strategy with the thrust and freestream mass flowrate remaining constant is proposed for the combined cycle engine, based on the steady state characteristics of turbine and ramjet units. Furthermore, the parametric performance simulation model of the engine is developed to verify the potential performance improvements generated by the application of rotating detonation technology, and analyze the application characteristics of the mode transition strategy formulated in this study. It is shown the lower initial Mach numbers of mode transition result in higher values of equivalent specific thrust but lower values of equivalent specific impulse during the transition mode. For the detonative combined cycle engine, the minimum value of initial Mach number of mode transition is below 2.0, which is much lower than that of the conventional turbine based combined cycle engine. Therefore, the performance during transition mode is expected to be improved with the application of rotating detonation technology.

The liquid oxygen/methane staged cycle liquid-rocket engine is one of the most potential rocket engines in the future for its higher performance, higher fuel density and reusable capacity. Two working states of this liquid-rocket engine named as full-load state and half-load state are defined in this paper. Based on this liquid-rocket engine, a dual-rocket-based-combined-cycle propulsion system with liquid oxygen /air/methane as propellants is therefore proposed. The dual-rocket-based-combined-cycle system has then five working modes: the hybrid mode, pure ejector mode, ramjet mode, scramjet mode and pure rocket mode. In hybrid mode, the booster and ejector rockets driven by the full-load liquid-rocket engine work together with the purpose of reducing thrust demand on ejector rocket. In scramjet mode, the fuel-rich burned hot gas generated by the half-load liquid-rocket engine is used as fuel, which is helpful to reduce the technical difficulty of scramjet in hypersonic speed. The five working modes of dual-rocket-based-combined-cycle are highly integrated based on the full- or half-load state of the liquid oxygen/methane staged cycle liquid-rocket engine, and the unified single type fuel of liquid methane is adopted for the whole modes. Then a preliminary design of a horizontal takeoff two-stage-to-orbit launch vehicle is conducted based on the dual-rocket-based-combined-cycle propulsion system. Under an averaged baseline thrust and specific impulse, the launch trajectory to reach a low Earth orbit at 100 km is optimized via the pseudo-spectral method subject to maximizing the payload mass. It is shown that the two-stage-to-orbit vehicle based on the dual-rocket-based-combined-cycle can achieve the payload mass fraction of 0.0469 and 0.0576 for polar mission and equatorial mission, respectively. Conclusively, insights gained in this paper can be usefully applied to a more detailed design of the dual-rocket-based-combined-cycle powered two-stage-to-orbit launch vehicle.

The present study was designed to explore the neuroprotective effects of docosahexaenoic acid (DHA) and/or vitamin E (VE) in vitro. The PC12 cells were pretreated with DHA and/or VE for 4 h, followed by 50 μmol L-1 Aβ25-35 treatments for another 48 h. The cells were then collected and used for the measurements of oxidative stress parameters. Real time-PCR and western blot were applied to measure fatty acid transporters, Nrf2 and its downstream antioxidant targets' gene and protein expression. Our results indicated that the Aβ25-35 treatment inhibited cellular growth, increased intracellular ROS generation and decreased the mitochondrial membrane potential. The Aβ25-35 treatment decreased the total antioxidant capacity (T-AOC), whereas it increased the MDA levels in neuron cells. Pretreatment of cells with VE or DHA could antagonize the Aβ25-35-mediated cell growth inhibition and mitochondrial membrane potential decline. Activation of the Nrf2 signaling pathway and regulation of CD36, SRB1 and FABP5 expression were observed in DHA- and DHA + VE-pretreated cells. Our results indicated a synergistic effect of DHA and VE in antagonizing the oxidative damage caused by Aβ25-35 in the PC12 cells. The results of the present study will shed light on the application of nutritional intervention for DHA and VE in preventing neuronal damage-related diseases.

An efficient and reliable flight Mach controller is specially needed for an Aircraft. A Flight Mach Fuzzy Controller (FMFC) based on modern Fuzzy control theory is designed for an Unmanned Aerial Vehicle (UAV) using a turbojet engine. The theory and process of designing control law is introduced and its control performance is optimized by changing the scaling factor. In order to evaluate the control performance, the mathematical simulation and hardware-in-the-loop simulation are carried out respectively, and the simulation results are compared. The evaluation shows good control performance to stabilize the UAV flight Mach number to the target Mach number quickly by controlling the engine work condition.

Peripheral blood gene expression intensity-based methods for distinguishing healthy individuals from cancer patients are limited by sensitivity to batch effects and data normalization and variability between expression profiling assays. To improve the robustness and precision of blood gene expression-based tumour detection, it is necessary to perform molecular diagnostic tests using a more stable approach. Taking breast cancer as an example, we propose a machine learning–based framework that distinguishes breast cancer patients from healthy subjects by pairwise rank transformation of gene expression intensity in each sample. We showed the diagnostic potential of the method by performing RNA-seq for 37 peripheral blood samples from breast cancer patients and by collecting RNA-seq data from healthy donors in Genotype-Tissue Expression project and microarray mRNA expression datasets in Gene Expression Omnibus. The framework was insensitive to experimental batch effects and data normalization, and it can be simultaneously applied to new sample prediction.

A new method for the inlet condition is proposed for the high-accuracy numerical simulation of supersonic reacting mixing layer by considering the conservation of mass, momentum and energy in the mixing process of two freestreams at the inlet. This method can ensure that all parameters at the inlet are compatible. Based on the inlet condition obtained from this method, direct numerical simulations of air/hydrogen supersonic reacting mixing layers are carried out, and the effect of the inlet condition is examined by comparing with that based on traditional inlet conditions. It is shown that the commonly used inlet conditions can lead to abnormal distributions of density and product of gas constant and temperature at the inlet, subsequently causing unreasonable results or even divergence in computation. These problems are avoided by using the proposed compatible inlet condition. The predicted profiles and flowfield are more reasonable, demonstrating the advantages of the proposal.

We investigate passive scalar mixing in spatially developing supersonic shear layer flows formed by two planar streams by means of large eddy simulation. After validation of the numerical procedures employing a high-order hybrid WENO/compact scheme by comparing the results of simulation with the results obtained from a well characterized experimental case, the effects of the convective Mach number, M c , flow velocity ratio, r = U 1 / U 2 , and fluid density ratio, s = ρ 1 / ρ 2 , between Stream 1 and Stream 2 on passive scalar mixing are considered by examining the variation of mixing layer thickness and the mixing efficiency represented by the transport of the passive scalar. M c is specified from 0.2 to 0.8. The evolution of large-scale coherent structures is well reproduced, with vortices undergoing rolling up, pairing, merging, and breaking up. The mixing layer thickness and mixing efficiency both decrease as M c increases. As s increases, the mixing layer thickness increases, and the mixing efficiency of an entrained fluid decreases. As r increases, the mixing layer thickness decreases while the mixing efficiency increases. While the present results are not applicable to the examination of micro-mixing properties, which require assessment by experimental methods or high computing cost direct numerical simulation, they are useful for evaluating the effects of different flow parameters on macro-performance, which is equally important for scramjet combustor design and evaluation in engineering.

Objective: The current study evaluated the relationship between circulating fat soluble vitamin status and cognition in aging Chinese population. Methods: A cross-sectional study was carried out in 1754 community residents aged 55-80 years aiming to evaluate the relationship between circulating α-tocopherol and retinol status and cognition. The effect of ApoE genetic polymorphism on the relationship between vitamins and cognition was also explored. Results: Our results indicated that serum retinol status positively correlated with cognitive performance; while, serum α-tocopherol (α-TOH)/retinol ratio negatively correlated with cognitive performance. Mild cognitive impairment (MCI) subject demonstrated higher serum α-TOH status (P < 0.05), α-TOH/retinol ratio (P < 0.01) and lower retinol status (P < 0.01) than normal subjects. Subjects with ApoE4 genotype have lower serum retinol level (P < 0.05) and higher α-TOH/retinol ratio (P < 0.01) than subjects with ApoE3 genotype. MCI-ApoE4 carriers demonstrated the worst cognitive performance (P < 0.05) and exhibited higher serum TC, α-TOH and α-TOH/retinol ratio levels (P < 0.05), and lower LDL-C, retinol and lipid-adjusted retinol status (P < 0.05). MCI-ApoE2 subjects showed higher serum TC, HDL-C content and α-TOH/retinol ratio (P < 0.05); and lower serum retinol and lipid-adjusted retinol status (P < 0.05). Conclusion: Lower circulating retinol and higher α-TOH/retinol ratio potentially predicts an increased risk for the development of cognitive decline in aging Chinese adults. ApoE2 or E4 carriers with higher circulating α-TOH/retinol ratio infer poor cognitive performance and an increased risk of developing MCI.

Quantum entanglement, the essential resource for quantum information processing, has rich dynamics under different environments. Probing different entanglement dynamics typically requires exquisite control of complicated system-environment coupling in real experimental systems. Here, by a simple control of the effective solid-state spin bath in a diamond sample, we observe rich entanglement dynamics, including the conventional asymptotic decay as well as the entanglement sudden death, a term coined for the phenomenon of complete disappearance of entanglement after a short finite time interval. Furthermore, we observe counter-intuitive entanglement rebirth after its sudden death in the same diamond sample by tuning an experimental parameter, demonstrating that we can conveniently control the non-Markovianity of the system-environment coupling through a natural experimental knob. Further tuning of this experimental knob can make the entanglement dynamics completely coherent under the same environmental coupling. Probing of entanglement dynamics, apart from its fundamental interest, may find applications in quantum information processing through control of the environmental coupling.

Background: Epidemiology studies have indicated an association of apolipoprotein E (ApoE) genetic polymorphism and circulating serum steroid hormone levels with the risk of Alzheimer’s disease (AD). The established physiologic relationship between apolipoproteins and steroid hormone indicate an important role of ApoE polymorphism in impacting the relationship between serum steroid hormones and cognition in the elderly population. Study Design: 500 Chinese adults aged between 50 and 75 participated in this community based cross-sectional study. Blood samples were collected in the morning for ApoE genotyping and serum parameter assessment. Cognitive performance of participants was evaluated by Montreal Cognitive Assessment (MoCA) test. Results: Age, gender, educational level, smoking and physical activity levels are factors associated with cognitive performance in this elderly older Chinese populationadults. Compared to the controlnormal subjects, MCI subjects demonstrated higher serum TC, HDL-C and estradiol status (P < 0.05). ApoE genotype difference of serum lipid profile was observed with a relatively higher mean serum TG levels in ApoE2 and ApoE4 carriers (P < 0.05), and lower mean serum HDL-C level in ApoE4 carriers (P < 0.05). Memory and delayed recall ability was serum estradiol level related; and subjects with higher circulating estradiol concentration exhibited lower memory and delayed recall ability (P < 0.05). The association of serum estradiol and cortisol concentration with cognitive performance was ApoE genotypes dependent. Poor cognitive performance was observed in ApoE2 and ApoE4 carriers with higher serum estradiol level (P < 0.05). Moreover, ApoE2 and ApoE4 carriers with higher serum cortisol status demonstrated decreased language ability (P < 0.05). Multiple logistic regression analysis indicates that subjects with higher serum estradiol status may susceptibly have an increased risk for MCI (OR = 2.004, 95% CI: 1.135, 3.540; P = 0.017). ApoE2 carriers with higher serum steroid levels may be potentially predisposed to an increased risk of MCI (OR = 3.353; 95% CI: 1.135, 9.907; P = 0.029). Conclusion: Cognitive outcomes in elderly older Chinese adults are associated with serum steroid hormone statesstatus. Higher serum steroid levels in ApoE2 carriers might pose an increased risk of MCI in the elderly.

Super knock induced by pre-ignition in highly boosted spark ignition engines can cause very high peak pressure, which may lead to severe engine damage. Although it is difficult to investigate the mechanism of super-knock due to its inherent randomness, the very high peak pressure implies that super knock may relate to detonation. In this study, a tube-like one-dimensional constant volume bomb, which simplifies the geometry of a real engine's combustion chamber near top dead center, was used to better understand the fundamental phenomenon underlying super knock. H 2 /O 2 mixture was used to maintain reaction intensity even at lower pressure than that in real highly boosted engines. Simultaneous high speed shadowgraphy and pressure measurement were conducted to study the effects of initial pressure and temperature on combustion mode and flame propagation. By comparing the frequencies of super knock pressure oscillation in the boosted engine and after-detonation pressure wave in the constant volume bomb, a relation can be found between the super knock and detonation. The experimental results also show that the detonation tendency of H 2 /O 2 mixture in the constant volume bomb increases with increasing initial pressure but decreases with increasing initial temperature, indicating that the mixture density i.e. energy density plays an important role in detonation onset.