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The entry of Cd into soil-rice systems is a growing concern as it can pose potential risks to public health. To derive regional soil Cd threshold, a total of 333 paired soil and rice samples was collected in Anhui Province, Eastern China. The results showed that the total soil Cd and soil Zn/Cd were the most significant variables contributing to Cd content in polished rice. The Chinese Soil Quality Standards might overestimate risk posed by Cd-contaminated soil for rice production in the mining area due to high Zn/Cd values of some mining-associated soils. Cd levels in polished rice can be predictable using stepwise multiple linear regression (MLR) model. However, the derived soil Cd threshold based on the MLR model would be unrealistically high. The classification and regression tree method (CART) performed well in simulating Cd levels in polished rice and can be used to derive soil Cd threshold instead of MLR to minimize the uncertainty.

Carbon fiber reinforced plastic (CFRP) thin-walled structures have been widely acknowledged as superior energy absorbers due to comprehensive advantages on crashworthiness and light weight. However, few studies have been reported concerning CFRP thin-walled structures with nonlinearly variable sectional dimensions along the longitudinal direction. Hence, in the present study, a novel CFRP functionally-graded conical square thin-walled structure with variable circumscribed diameter (functionally-graded conical square tube, FGCST) is proposed and comprehensively investigated. Specifically, finite element (FE) models of FGCST under multi-angle crushing loading are first built and validated. Second, a comprehensive crashworthiness comparison among the FGCST, the conventional CFRP conical square tube (CST) and the CFRP straight square tube (SST) under multi-angle crushing loading is executed to explore the relative merits of FGCST over others. Third, a parameter study is implemented on FGCST to explore the action laws of its structural parameters on its overall crashworthiness under multi-angle crushing loading. Finally, the FGCST is multi-objective crashworthiness optimized for maximizing overall specific energy absorption (SEA θ ) and minimizing overall peak crushing force (PCF 0 ) simultaneously through Taguchi method coupled with grey relational analysis (GRA). The optimized FGCST obtains 6.06% higher of SEA θ and meanwhile 40.58% lower of PCF 0 compared with the baseline design, thus demonstrating good potential as a superior candidate for vehicle collision energy absorbers.

Abstract Background Venous thromboembolism (VTE) is a common postoperative complication in patients undergoing surgery for gastric cancer (GC). Although VTE incidence may vary among cancers, guidelines rarely stratify preventive methods for postoperative VTE by cancer type. The risk of VTE in patients undergoing surgery for GC remains unclear. Methods A systematic review and meta-analysis was undertaken to determine the risk of VTE after GC surgery and discuss the clinical value of pharmacological thromboprophylaxis in these cases. Medline, Embase, Web of Science, and Cochrane Library databases were searched for articles published from their inception to September 2022. Results Overall, 13 studies (111,936 patients) were included. The overall 1-month incidence of VTE, deep vein thrombosis (DVT), and pulmonary embolism (PE) after GC surgery was 1.8% (95% CI, 0.8–3.1%; I²=98.5%), 1.2% (95% CI, 0.5–2.1%; I²=96.1%), and 0.4% (95% CI, 0.1–1.1%; I²=96.3%), respectively. The prevalence of postoperative VTE was comparable between Asian and Western populations (1.8% vs. 1.8%; P > 0.05). Compared with mechanical prophylaxis alone, mechanical plus pharmacological prophylaxis was associated with a significantly lower 1-month rate of postoperative VTE and DVT (0.6% vs. 2.9% and 0.6% vs. 2.8%, respectively; all P 0.05). The 1-month postoperative incidence of VTE was not significantly different between laparoscopic and open surgery (1.8% vs. 4.3%, P > 0.05). Conclusion Patients undergoing GC surgery do not have a high risk of VTE. The incidence of VTE after GC surgery is not significantly different between Eastern and Western patients. Mechanical plus pharmacological prophylaxis is more effective than mechanical prophylaxis alone in postoperative VTE prevention. The VTE risk is comparable between open and laparoscopic surgery for GC.

Abstract Background Immunotherapy is currently applied in the first-line treatment regimens for numerous advanced cancers, especially advanced lung cancer. Immune-related adverse events (irAEs) resulting from immunotherapy can vary in severity and cause a substantial symptom burden to patients. However, there are limited data on symptom burden in patients with advanced lung cancer following immunotherapy. To address this deficit, this study aims to provide insight into the symptom burden and severity through patient-reported outcome measurements and conduct an analysis of temporal trends and clinical consequences of symptom burden in patients with advanced lung cancer receiving combination immunotherapy. Methods We will prospectively recruit 168 eligible patients from 14 hospitals in China. Eligible patients will be aged ≥ 18 years, pathologically diagnosed with locally advanced or stage IV primary lung cancer without surgical indications, and agreed to receive immunotherapy in combination with other therapies. The primary outcome of this study is the symptom burden of patients during the immunotherapy course. Longitudinal symptom data will be collected using the MD Anderson Symptom Inventory–Lung Cancer module (MDASI-LC) and the symptomatic irAEs scale at baseline (once before treatment) and weekly after treatment, until 1 month after the last treatment cycle has been completed. The trajectory of symptom burden following combination immunotherapy will be depicted, and by linking it to clinical outcomes (the secondary outcome and exploratory outcome of this study), the consequence of symptom burden in patients with advanced lung cancer receiving combination immunotherapy will be examined further. Discussion This study intends to establish longitudinal symptom trajectories in patients with lung cancer receiving immunotherapy, and explore its association with clinical outcomes. These findings may serve as an important reference for clinicians in the symptomatic management of patients with lung cancer receiving immunotherapy. Trial registration number ChiCTR2200061540. Registered on June 28, 2022.

In this paper, a novel thin-walled double-hexagonal crash box is first proposed and then multi-objective robust optimized for better overall crashworthiness under multi-angle impact loading, using a proposed hybrid method combining aluminum foam-filling and Taguchi-grey relational analysis (GRA). Specifically, the finite element (FE) models of the regularly-shaped double-hexagonal column (DHC) extracted from original irregularly-shaped crash box under multi-angle impact loading, including hollow (H-DHC) and foam-filled (F-DHC), are first built and validated by experiments. On this basis, a comprehensive crashworthiness comparison is conducted to explore relative merits of F-DHC over original H-DHC under multi-angle impact loading. After that, the F-DHC is multi-objective robust optimized for maximizing overall specific energy absorption (SEA θ ) and minimizing overall initial peak crushing force (IPCF 0 ) simultaneously under multi-angle impact loading, using a hybrid method of Taguchi-GRA. At last, a bumper-crash box integrated crashworthiness analysis under multi-angle impact loading is executed to further verify the optimization. The optimal F-DHC and the optimized crash box within the optimal F-DHC demonstrate evident improvement of crashworthiness compared to their respective initial designs, indicating aluminum foam-filling combined with Taguchi-GRA could be an effective approach for multi-objective robust optimization of the novel crash box and other similar vehicle structures.

ObjectiveTo investigate the effect of primary debulking surgery (PDS), NACT followed by interval debulking surgery (NACT-IDS), and chemotherapy alone on the prognosis of FIGO stage IV epithelial ovarian cancer (EOC) with different metastatic patterns.MethodsWe retrospectively analyzed 133 cases of FIGO stage IV EOC with pleural effusion (stage IVA), parenchymal metastases (stage IVB), or extra-abdominal lymph node metastases (stage IVB) at our Hospital between January 2014 and July 2021.ResultsAmong 133 cases with stage IV disease, 16.5% (n=22) presented with pleural effusion, 46.6% (n=62) with parenchymal metastases, and 36.9% (n=49) with extra-abdominal lymph node metastases. Regardless of the metastatic patterns, the 90.2% (n=120) of cases who underwent PDS/NACT-IDS exhibited a significantly superior overall survival (OS) compared to the 9.8% cases (n=13) who received chemotherapy alone (32 vs 17 months, p=0.000). The cohort was further stratified into 58 cases (48.3%) with R0, 41 cases (34.2%) with R1, and 21 cases (17.5%) with R2. The median OS of cases with R0 was significantly better than that of cases with R1/R2 (74 vs 27 months, p=0.000). There was no significant difference in median OS between PDS and NACT-IDS (43 vs 31 months, p=0.676), as well as between FIGO IVA and IVB (35 vs 31 months, p=0.582). Additionally, the metastatic patterns and the number of neoadjuvant chemotherapy cycles (≤4 or >4) did not demonstrate any prognostic significance for median OS (p=0.820 and 33 vs 26 months, p=0.280, respectively).ConclusionRegardless of FIGO IVA and IVB stages or metastatic patterns, patients diagnosed with stage IV EOC may benefit from cytoreductive surgery with abdominal R0, compared with chemotherapy alone.

We explore individual differences in tiger personality. We first asked—is there evidence of personality dimensions (analogous to the Big Five in human personality research) in the Amur tiger? We then asked, are any discoverable personality dimensions associated with measured outcomes, including group status, health and mating frequency? 152 of our participating tigers live in the world's largest semi-wild tiger sanctuary in North Eastern China. Our second sample of 96 tigers also lives in a sanctuary. Having two samples allowed us to assess the replicability of the personality dimensions or factors reported in our first sample. We found that two factors (explaining 21% and 17% of the variance among items) which we call, for descriptive ease, Majesty and Steadiness, provide the best fit to the data. Tigers that score higher on Majesty are healthier, eat more live prey, have higher group status (among other tigers as assessed by human raters) and mate more often. We provide some ethological context to put flesh on the quantitative bones of our findings concerning these magnificent and charismatic animals.

ObjectiveDue to the interaction of leukocytes with platelets and coagulation factors, they may in turn play a role in hemostasis or the formation of thrombi. This study aimed to investigate the association of leukocytosis on admission with an increased risk of acute lower-extremity deep venous thrombosis (LEDVT) in elderly patients with primary intracerebral hemorrhage (ICH).MethodsThis was a single-center, retrospective observational study of consecutive patients observed with spontaneous ICH aged 60 years or above at Lanzhou University Second Hospital from January 2017 to September 2021. Clinical data and demographic information were collected and analyzed. Univariate and multivariate analyses were conducted to identify independent risk factors of acute LEDVT. One-to-one matching was implemented to balance important patient characteristics by the groups' propensity score matching (PSM) analysis.ResultsA total of 371 elderly patients with primary ICH fulfilled requirements for inclusion and exclusion, of whom 33 (8.89%) experienced LEDVT. Leukocyte counts were statistically higher in the LEDVT group compared to the non-LEDVT group [12.89 (8.80–14.61) × 109 cells/L vs. 8.31 (6.60–10.75) × 109 cells /L, p < 0.001]. Multivariate logistic regression models adjusted for several potential confounding factors were performed, and leukocytes were consistently a significant independent predictor of LEDVT. The optimal cut-off value of leukocyte counts calculated from the receiver operating characteristic (ROC) curve to predict LEDVT was 10.22 × 109 cells /L (area under the curve:0.714, 95%CI 0.665–0.759; the sensitivity was 72.73%; the specificity was 71.01%) in elderly patients with primary ICH. After one-to-one PSM, compared to the matched non-LEDVT group, the matched LEDVT group had significantly higher leukocyte counts [11.98 (8.40–13.94) × 109 cells/L vs. 6.12 (4.68–12.00) × 109 cells/L, p = 0.003]. After PSM, the ROC curve was plotted for leukocytes as a predictor of LEDVT, with an AUC of 0.722 (95%CI 0.593–0.828, p = 0.001; the sensitivity was 87.10%, and the specificity was 61.29%). Elevated leukocytes remained independently significant as predictors of LEDVT in elderly patients with primary ICH.ConclusionLeukocyte at admission is an independent risk factor of LEDVT in elderly patients with primary ICH.

Abstract Background Primary debulking surgery (PDS) is the main treatment for patients with advanced ovarian cancer, and neoadjuvant chemotherapy (NACT) is for bulky stage III-IV patients who are poor surgical candidates and/or for whom there is a low likelihood of optimal cytoreduction. NACT can increase the rate of complete cytoreduction, but this advantage has not translated to an improvement in survival. Therefore, we aimed to identify factors associated with the survival of patients who received NACT followed by interval debulking surgery (IDS). Methods A retrospective study was conducted in FIGO stage IIIC-IV epithelial ovarian cancer patients who underwent PDS or IDS in our center between January 1st, 2013, and December 31st, 2018. Results A total of 273 cases were included, of whom 20 were lost to follow-up. Progression-free survival (PFS) and overall survival (OS) of the IDS and PDS groups were found to be similar, although the proportion of patients in stage IV and serum carbohydrate antigen 125 (CA125) levels before treatment in the IDS group were significantly higher than that in the PDS group. Body mass index (BMI), CA125 level before IDS, residual disease after surgery, and the interval between preoperative and postoperative chemotherapy were all found to be independent prognostic factors for PFS; FIGO stage, residual disease after surgery, and CA125 level before IDS were independent prognostic factors for OS. We found that PFS and OS were both significantly longer in patients with normal CA125 levels before IDS and when the interval between preoperative and postoperative chemotherapy was

In the seismic design and analysis of important structures, ground motion time histories are generally required as the input for the conduction of seismic response history analysis. Taking a selected spectrum as the target, the approaches for generating spectral compatible time histories based on artificial or synthetic ground motion and real recorded earthquake ground motion, respectively, are commonly used and discussed in this review. The pure artificial approaches have relative higher effectiveness and computational efficiency, while the approaches by adjusting the real records could simulate the nonstationary in both time domain and frequency domain.

Micrometre level ranging accuracy between satellites on-orbit relies on the high-precision calibration of the antenna phase center (APC), which is accomplished through properly designed calibration maneuvers batch estimation algorithms currently. However, the unmodeled perturbations of the space dynamic and sensor-induced uncertainty complicated the situation in reality; ranging accuracy especially deteriorated outside the antenna main-lobe when maneuvers performed. This paper proposes an on-orbit APC calibration method that uses a reinforcement learning (RL) process, aiming to provide the high accuracy ranging datum for onboard instruments with micrometre level. The RL process used here is an improved Temporal Difference advantage actor critic algorithm (TDAAC), which mainly focuses on two neural networks (NN) for critic and actor function. The output of the TDAAC algorithm will autonomously balance the APC calibration maneuvers amplitude and APC-observed sensitivity with an object of maximal APC estimation accuracy. The RL-based APC calibration method proposed here is fully tested in software and on-ground experiments, with an APC calibration accuracy of less than 2 mrad, and the on-orbit maneuver data from 11–12 April 2022, which achieved 1–1.5 mrad calibration accuracy after RL training. The proposed RL-based APC algorithm may extend to prove mass calibration scenes with actions feedback to attitude determination and control system (ADCS), showing flexibility of spacecraft payload applications in the future.

To explore the application feasibility of high-strength steel in skeleton columns of precipitator casing structures, the bearing behavior of axially compressed H-section high-strength steel columns was investigated by the nonlinear finite element method by considering the stressed-skin effect of wallboard. When the column yield strength does not exceed 460 MPa, the column undergoes elasto-plastic interactive buckling, which means the steel strength can be fully utilized. For the column strength of 550 MPa or 690 MPa, the wallboard yield failure occurs, owing to excessive loading of the relatively weak wallboard, and column stress magnitude is usually in the elastic range without the full utilization of steel strength, whereas if the wallboard is stiff enough, columns will still undergo buckling failure. A welding residual stress measuring test was conducted to validate the residual stress generation simulation via the thermal-mechanical coupling finite element method. Concerning the geometrical imperfections and residual stresses, it was found that their influence becomes less severe when the column steel strength increases. The bearing capacity can be improved by increasing the wallboard thickness and stiffener stiffness, or reducing the wallboard width, the stiffener spacing, the width-to-thickness ratio of column flange, the height-to-thickness ratio of column web, and column torsional slenderness ratio. Column material can be fully utilized when column steel strength does not exceed 460 MPa. Hence, employing high-strength steel is reasonable. When the column steel strength is equal to or higher than 550 MPa, wallboard strength should be sufficient to ensure that the column failure occurs before wallboard failure. In such cases, high-strength steel should be used carefully.

Alongside the reform and opening-up policies in China since 1978, there has been a transformation of China’s governmental functions and of its media system. While adapting to the complex political process towards democratization, the Chinese Communist Party media have further expanded their dual identity as both organizational communicator and mass communicator, and are involved in Chinese political communication in a variety of ways. To improve the role of internal organizational communication, the Party media have extended their sphere of activity from traditional Internal Reference (xinwen neican 新闻内参) to Online Public Opinion Monitoring (yuqing jiance 舆情监测) and Media Think Tank Consultation (meiti zhiku 媒体智库). As leaders in China’s market-oriented media reform and tech-driven media integration, the Chinese Party media have remained dominant and privileged agents in China’s mass media system, and active participants in social political communication in a number of ways, from traditional policy publicity, to media supervision and timely external opinion guiding.

In the process of large-scale urban construction, large amounts of waste slurry are produced. The slurry has a high water content and is difficult to precipitate naturally, resulting in low treatment efficiency. To improve the treatment efficiency of slurry, a variety of inorganic and organic polymer flocculants were used to carry out flocculation settlement tests on the slurry. The changes in the slurry properties and the filtration dewatering effect after flocculation were tested. The results show that the addition of flocculant makes the slurry particles form aggregates, which leads to rapid precipitation of the slurry. The use of an inorganic flocculant significantly reduced the zeta potential of the slurry. Organic polymer flocculant, however, had little effect on the slurry potential, but did cause the slurry to produce larger size aggregates, resulting in a better flocculation effect than inorganic flocculant. Inorganic flocculants and organic flocculants can improve the pressure filtration dewatering performance of slurry. CPAM12 (cationic polyacrylamide, with a relative molecular weight of 12 million Daltons) had the best overall effect. The formation of aggregates after flocculation and the change in the nonuniformity coefficient (Cu) were the main cause of improvement of pressure filtration dewatering performance of the slurry. When Cu decreases from 11.85 to 8.75, the time required for pressure filtration stabilization is shortened by 70%. The nonuniformity coefficient of flocculated slurry can be used to evaluate flocculants, determine the optimal dosage, and predict the dewatering effect.

Objective: In view of the poor prognosis and difficulties in the diagnosis of osteosarcoma, and the functionality of microRNA-Let7A in different types of human cancers, our study aimed to explore the diagnostic and prognostic values of microRNA-Let7A for osteosarcoma. Methods: A total of 39 patients with osteosarcoma and 19 normal healthy people were included in this study. All patients received surgical resection, and tumor tissues as well as pericarcinomatous tissues were collected during surgical operation. Venous blood (2 ml) was extracted from each participant. Expression of microRNA-Let7A in tumor tissues and pericarcinomatous tissues, and expression of E2F2 and microRNA-Let7A in blood of each participant was detected by qRT-PCR. ROC analysis was performed to evaluate the diagnostic values of blood E2F2 and microRNA-Let7A for osteosarcoma, and prognostic values of microRNA-Let7A for osteosarcoma was evaluated by survival curve comparisons. Results: Expression level of microRNA-Let7A was significantly lower in tumor tissues than that in pericarcinomatous tissues. MicroRNA-Let7A expression in blood was significantly downregulated in osteosarcoma patients compared with normal control. Expression of microRNA-Let7A was negatively correlated with the expression of E2F2 in blood of osteosarcoma patients. Compared with E2F2, blood microRNA-Let7A can more effectively predict osteosarcoma. Overall survival rate of osteosarcoma patient with low blood expression level of miRNA-let-7a was significantly lower than that of patients with high blood expression level of miRNA-let-7a. Conclusion: Blood microRNA-Let7A is a promising diagnostic and prognostic biomarker for osteosarcoma. Keywords: Osteosarcoma, MicroRNA-Let7A, Venous blood, qRT-PCR, ROC, Pericarcinomatous

In this study, submillimeter level accuracy K-band microwave ranging (MWR) equipment is demonstrated, aiming to verify the detection of the Earth’s gravity field (EGF) and digital elevation models (DEM), through spacecraft formation flying (SFF) in low Earth orbit (LEO). In particular, this paper introduces in detail an integrated BeiDou III B1C/B2a dual frequency receiver we designed and developed, including signal processing scheme, gain allocation, and frequency planning. The receiver matched the 0.1 ns precise synchronize time-frequency benchmark for the MWR system, verified by a static and dynamic test, compared with a time interval counter synchronization solution. Moreover, MWR equipment ranging accuracy is explored in-depth by using different ranging techniques. The test results show that MWR achieved 40 μm and 1.6 μm/s accuracy for ranging and range rate during tests, using synchronous dual one-way ranging (DOWR) microwave phase accumulation frame, and 6 μm/s range rate accuracy obtained through a one-way ranging experiment. The ranging error sources of the whole MWR system in-orbit are analyzed, while the relative orbit dynamic models, for formation scenes, and adaptive Kalman filter algorithms, for SFF relative navigation designs, are introduced. The performance of SFF relative navigation using MWR are tested in a hardware in loop (HIL) simulation system within a high precision six degree of freedom (6-DOF) moving platform. The final estimation error from adaptive relative navigation system using MWR are about 0.42 mm (range/RMS) and 0.87 μm/s (range rate/RMS), which demonstrated the promising accuracy for future applications of EGF and DEM formation missions in space.

Lightweight design is one of the important ways to reduce automobile fuel consumption and exhaust emissions. At the same time, the fatigue life of automobile parts also greatly affects vehicle safety. This paper proposes a multi-objective reliability optimization method by integrating Monte Carlo simulation (MCS) with the NSGA-II algorithm coupled with entropy weighted grey relational analysis (GRA) for lightweight design of the lower control arm of automobile Macpherson suspension. The dynamic load histories of the control arm were extracted through dynamic simulations of a rigid-flexible coupling vehicle model on virtual proving ground. Then, the nominal stress method was used to predict its fatigue life. Six design variables were defined to describe the geometric dimension of the control arm, while mass and fatigue life were taken as optimization objectives. The multi-objective optimization design of the control arm was carried out based on the Kriging surrogate model and NSGA-II algorithm. Aiming at the uncertainty of design variables, the reliability constraint was added to the multi-objective optimization to improve the reliability of the fatigue life of the control arm. The optimal design of the control arm was determined from Pareto solutions by entropy weighted grey relational analysis (GRA). The optimization results show that the mass of the control arm was reduced by 4.1% and the fatigue life was increased by 215.8% while its reliability increased by 7.8%. The proposed multi-objective reliability optimization method proved to be feasible and effective for lightweight design of a suspension control arm.

In the past studies, the influence of wheel structure design and optimization on the aerodynamic drag of car and heat transfer performance of brake disc was less studied. To study the influence mechanism, the finite element model for wheel aerodynamic analysis was established using computational fluid dynamic method and the correctness of the model was verified by the wind tunnel test data. The influence mechanism of the flow field on aerodynamic drag of car and wheel and heat transfer performance of brake disc was studied. The influence of wheel disc structure on aerodynamic drag coefficient of the car and average convective heat transfer coefficient of the brake discs was studied. The parametric model of the wheel under the computational fluid dynamic analysis was established using mesh morphing technology. A total of 100 and 10 sample points were extracted using the Hammersley Design and Optimal Latin Hypercube Design, respectively, to fit the radial basis function surrogate model and test the accuracy of the surrogate model. Based on the established surrogate model, taking the minimum of the wheel mass, the minimum of the aerodynamic drag coefficient of the car and the maximum of the average surface convective heat transfer coefficient of brake discs as objectives and design variables of wheel as constraints to ensure the wheel structural strength, the non-dominated sorting genetic algorithm was adopted to carry out multi-objective optimization design for the wheel. Pareto frontier was obtained and a compromise solution was selected as the optimization design result. After the optimization design, the wheel mass is reduced by 8.28%, the aerodynamic drag coefficient of the car is reduced by 3.17% and the average surface convective heat transfer coefficient of brake discs is increased by 9.31%.

In order to reduce the negative effect of lightweighting of suspension components on vehicle dynamic performance, the control arm and torsion beam widely used in front and rear suspensions were taken as research objects for studying the lightweight design method of suspension components. Mesh morphing technology was employed to define design variables. Meanwhile, the rigid–flexible coupling vehicle model with flexible control arm and torsion beam was built for vehicle dynamic simulations. The total weight of control arm and torsion beam was taken as optimization objective, as well as ride comfort and handling stability performance indexes. In addition, the fatigue life, stiffness, and modal frequency of control arm and torsion beam were taken as the constraints. Then, Kriging model and NSGA-II were adopted to perform the multi-objective optimization of control arm and torsion beam for determining the lightweight scheme. By comparing the optimized and original design, it indicates that the weight of the optimized control arm and torsion beam are reduced 0.505 kg and 1.189 kg, respectively, while structural performance and vehicle performance satisfy the design requirement. The proposed multi-objective optimization method achieves a remarkable mass reduction, and proves to be feasible and effective for lightweight design of suspension components.

Spacecraft formation flying (SFF) in highly elliptical orbit (HEO) has attracted a great deal of attention in many space exploration applications, while precise guidance, navigation, and control (GNC) technology—especially precise ranging—are the basis of success for such SFF missions. In this paper, we introduce a novel K-band microwave ranging (MWR) equipment for the on-orbit verification of submillimeter-level precise ranging technology in future HEO SFF missions. The ranging technique is a synchronous dual one-way ranging (DOWR) microwave phase accumulation system, which achieved a ranging accuracy of tens of microns in the laboratory environment. The detailed design and development process of the MWR equipment are provided, ranging error sources are analyzed, and relative orbit dynamic models for HEO formation scenes are given with real perturbations considered. Moreover, an adaptive Kalman filter algorithm is introduced for SFF relative navigation design, incorporating process noise uncertainty. The performance of SFF relative navigation while using MWR is tested in a hardware-in-the-loop (HIL) simulation system within a high-precision six degrees of freedom (6-DOF) moving platform. The final range estimation errors from MWR using the adaptive filter were less than 35 μm and 8.5 μm/s for range rate, demonstrating the promising accuracy for future HEO formation mission applications.

In this work, several metal oxides and zinc salts were used to catalyze propylene carbonate (PC) synthesis from urea and propylene glycol (PG). According to the results of catalytic test and characterization, the catalytic pattern of ZnO was different from that of other metal oxides such as CaO, MgO and La2O3, but similar to that of zinc salts. In fact, the leaching of Zn species took place during reaction for ZnO. And ZnO was found to be the precursor of homogenous catalyst for reaction of urea and PG. Thus, the relationship between the amount of dissolved zinc species and the catalytic performance of employed ZnO was revealed. In addition, a possible reaction mechanism over ZnO was discussed based on the catalytic runs and the characterization of XRD, FTIR, and element analysis.

Flexible polyurethane (PU) foams comprising various additive components were synthesized to improve their acoustic performances. The purpose of this study was to investigate the effects of various additive components of the PU foams on the resultant sound absorption, which was characterized by the impedance tube technique to obtain the incident sound absorption coefficient and transmission loss. The maximum enhancement in the acoustic properties of the foams was obtained by adding fluorine-dichloroethane (141b) and triethanolamine. The results showed that the acoustic absorption properties of the PU foams were improved by adding 141b and triethanolamine and depended on the amount of the water, 141b, and triethanolamine.

The present study was conducted to scrutinize the pharmacological effect of Estragole (ESG) against CFA-induced arthritis in rats. The rats underwent induction of arthritis using the administration of CFA and after that, the rats were randomly divided into five different groups, where three groups correspond to diverse dosages of ESG, and the other two were control and CFA-arthritic control. Results of the study suggested that ESG in a dose-dependent manner, improves body weight and arthritis score of rats as evidenced by reduction of hind-paw volume. ESG also improved the antioxidant status of rats by reducing MDA levels and enhancing the concentration of endogenous antioxidants SOD and GPx. The level of pro-inflammatory cytokines was also found to be reduced in the case of ESG treated group as compared to CFA-group. In a western blot analysis, ESH showed downregulation of p-JAK-2/STAT-3. The study provided concrete evidence for the protective effect of ESG against rheumatoid arthritis in rats. [ABSTRACT FROM AUTHOR]