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Lightweight steel-aluminum structures have broad application prospects because of their lowering weight characteristics, however, the corrosion of welding-brazing joints in steel-aluminum structures is less concerned or studied. In this paper, the corrosion behavior of the laser-MIG (metal inert gas) hybrid welding-brazing joints of steel-aluminum is investigated through the tests and analysis of salt spray, immersion, and electrochemistry. The salt spray and immersion tests show that obvious galvanic corrosion occurs at the welded joints, in which the aluminum side is seriously corroded while the steel side is not corroded. The open-circuit potential (OCP) values of the aluminum alloy and the weld metal are similar (approximately −0.48 V), and the stainless steel has a higher OCP value of −0.33 V. The corrosion resistance of the weld metal is lower than aluminum- and steel-based materials. The corrosion resistance of the joints is controlled by the aluminum alloy part of the two metals based on the OCP and electrochemical impedance spectroscopy (EIS) analysis. A possible corrosion process schematic for the physical/chemical properties of a welding-brazing joint immersed in a sodium chloride solution is proposed according to EIS.

Interferons (IFNs) including type I/III IFNs are the major components of the host innate immune response against porcine epidemic diarrhea virus (PEDV) infection, and several viral proteins have been identified to antagonize type I/III IFNs productions through diverse strategies. However, the modulation of PEDV infection upon the activation of the host’s innate immune response has not been fully characterized. In this study, we observed that various IFN-stimulated genes (ISGs) were upregulated significantly in a time- and dose-dependent manner in LLC-PK1 cells infected with the PEDV G2 strain FJzz1. The transcriptions of IRF9 and STAT1 were increased markedly in the late stage of FJzz1 infection and the promotion of the phosphorylation and nuclear translocation of STAT1, implicating the activation of the JAK-STAT signaling pathway during FJzz1 infection. In addition, abundant type I/III IFNs were produced after FJzz1 infection. However, type I/III IFNs and ISGs decreased greatly in FJzz1-infected LLC-PK1 cells following the silencing of the RIG-I-like receptors (RLRs), including RIG-I and MDA5, and the Toll-like receptors (TLRs) adaptors, MyD88 and TRIF. Altogether, FJzz1 infection induces the production of type-I/III IFNs in LLC-PK1 cells, in which RLRs and TLRs signaling pathways are involved, followed by the activation of the JAK-STAT signaling cascade, triggering the production of numerous ISGs to exert antiviral effects of innate immunity.

内蒙古维拉斯托稀有金属-锡多金属矿床位于大兴安岭南段西坡，是一个以锡为主，共伴生锌、钨、铜、钼、铌、钽、锂和铷的大型矿床。该矿床以发育铌、钽、铷、锂矿化有别于大兴安岭南段的其他锡多金属矿床。本文对维拉斯托地区的北大山岩体和维拉斯托岩体开展了LA-ICP-MS锆石U-Pb定年、全岩地球化学研究和锆石Lu-Hf同位素分析。北大山岩体和维拉斯托岩体的结晶年龄分别为140±2Ma和137±1Ma~138±1Ma。2个岩体均具有高硅、富碱、贫铁镁钙特征，主体为高钾钙碱性的弱过铝质碱长花岗岩，轻重稀土分馏不明显，呈现出显著的负铕异常。2个岩体均富集Rb、Th、U、K、Ta、Hf和轻稀土元素，强烈亏损Ba、Sr、P、Eu和Ti等元素。与北大山岩体相比，维拉斯托岩体有更低的稀土总量，更明显的Eu负异常，展示了明显的稀土元素四分组效应；Ba、Sr、Eu、Ti和Y亏损更强烈。二者的时空关系和地球化学特征表明2个岩体为同一期岩浆活动不同演化阶段的产物，岩浆演化过程经历了钾长石、斜长石、黑云母、独居石、榍石、褐帘石、磷灰石、磷钇矿、锆石和钛铁矿的分离结晶，维拉斯托岩体还发生了熔体-流体相互作用。北大山岩体和维拉斯托岩体锆石的eHf（t）值分别为5.4~8.6和4.2~9.9，两阶段Hf同位素模式年龄分别为643~847Ma和556~921Ma，表明它们的岩浆源区为起源于亏损地幔的新元古代新生地壳物质。北大山岩体属于高分异I型花岗岩，维拉斯托岩体发育钠长石、天河石、黄玉、锂云母和萤石，属于超分异的Li-F花岗岩。花岗质岩浆的高程度分离结晶和熔体-流体相互作用是形成维拉斯托超分异花岗岩并发生稀有金属-锡多金属成矿作用的重要控制因素。维拉斯托稀有金属-锡多金属矿床属于岩浆-热液矿床。维拉斯托地区的早白垩世花岗质岩石形成于伸展环境。

道伦达坝中型铜钨锡矿床位于大兴安岭南段，矿体呈脉状赋存于二叠系板岩及华力西期黑云母花岗岩的断裂破碎带中。道伦达坝矿床发育铜矿体、锡矿体、钨矿体、铜钨矿体、铜锡矿体、钨锡矿体和铜钨锡矿体。矿床的成矿过程可以划分为石英-萤石-白云母-电气石-锡石-黑钨矿阶段（Ⅰ阶段）、石英-萤石-黑钨矿-黄铜矿-毒砂-磁黄铁矿阶段（Ⅱ阶段）、石英-萤石-绢云母-黄铜矿-磁黄铁矿-黄铁矿-银矿物阶段（Ⅲ阶段）和方解石-石英-萤石-黄铁矿阶段（Ⅳ阶段）。道伦达坝矿床外围的张家营子岩体中的细粒花岗岩的LA-ICP-MS锆石U-Pb年龄为136.1±0.4Ma。Ⅱ阶段Cu-W共生矿体中2件独居石的LA-ICP-MS U-Pb年龄分别为136.0±2.3Ma和135.1±2.2Ma。Ⅲ阶段Cu矿体中1件独居石的LA-ICP-MS U-Pb年龄为134.7±2.8Ma。Ⅲ阶段铜矿体中1件绢云母的40Ar-39Ar坪年龄为138.8±0.47Ma，等时线年龄为140.0±1.1Ma。系统的定年结果表明，道伦达坝矿床的铜钨矿体和铜矿体均形成于早白垩世，它们属于同一个成矿系统；成矿与早白垩世高分异花岗岩有密切的成因联系。

Two-stage turbocharging technology is a solution to reduce turbo lag and improve the performance of engine and matching characteristics at high altitudes. In the present study, an engine testing system was established to study combustion performance and matching characteristics of a regulated two-stage turbocharging system (R2S) at different simulated altitudes. An equivalent turbocharger concept was put forward aiming to simplify the R2S with three bypass valves, and the total equivalent turbine flow area and equivalent efficiency of the R2S were obtained based on a theoretical study. Intake characteristics, combustion process, torque, power and fuel economy of the diesel engine matched with R2S were analyzed at different altitudes. The results showed that compared with 0 m, intake pressure, maximum combustion pressure, cumulative heat release, heat release rate decreased by 36.5%, 33.6%, 33.5%, 21.6%, −8.9% at 4000 r/min, and decreased by 12.3%, 2.9%, 16.4%, 8.8%, −5.4% at the speed of 2000 r/min at the altitude of 5000 m. The torque, fuel consumption and fuel consumption rate decreased by 10.1%, 5.1% and 5.4% at engine speed of 2000 r/min and by 35.7%, 27.6% and 8.9% at engine speed of 4000 r/min at 5000 m.

A variable geometry turbocharger in series with a variable geometry turbocharger (Twin-VGT) system was designed to improve engine power at high altitudes. The influence of altitudes on the performance of the Twin-VGT system was investigated in the perspective of available exhaust energy. The interaction between exhaust flow characteristics of Twin-VGT and openings of Twin-VGT vanes was theoretically analyzed at different altitudes. Meanwhile, a model of a diesel engine matched with the Twin-VGT system was built to study the matching performance of the Twin-VGT system with engine at different altitudes. The optimal opening maps of both high-pressure and low-pressure VGT vanes at high altitudes were obtained to achieve the maximum engine power. The results showed that the optimal openings of high-pressure and low-pressure VGT vanes decreased with increase in altitudes. The operating points of the two-stage compressors located at the high efficiency region and the compressor efficiency region both exceeded 62% at different altitudes. The global expansion ratio increased with increase in altitudes and reached 4.9 at 5500 m. Compared with the VGT in series with a fixed geometry turbocharger on testing bed, exhaust energy of Twin-VGT turbines at low speeds was utilized reasonably and global pressure ratio increased by 0.69–0.94, while brake-specific fuel consumption decreased by 11.24–33.62% under low speeds above altitudes of 2500 m.

Additional file 4: Supplementary material 3: Multivariate Cox regression model including smoking information (keep or remove missing values). As smokers or patients with specific malignancies could have increased CEA levels without any correlation with COVID-19, all patients with primary malignancy were excluded from the study. Furthermore, in order to identify the association between CEA levels and smoking, two subgroup Cox proportional hazard regression models including smoking status (keep or remove missing values) were constructed, suggesting that the CEA level (HR 0.547; 95% CI 0.318 to 0.940; P = 0.037) (remove missing values) (HR 0.620; 95% CI 0.384 to 0.990; P = 0.048) (keep missing values) was still an independent prognostic indicator for COVID-19 patients.

Additional file 1. Table S1: Results of Kaplan–Meier survival analysis of 17 laboratory values with more than 20% missing data.

Additional file 3. Supplementary material 2: Converged multivariate Cox regression model including 11 potential prognostic laboratory indicators with significance in univariate analysis (keep missing values). In the cohort keeping missing values, a total of 11 regression models were converged and CEA was an independent prognostic factor in all multivariate models. Additionally, patients with normal PLT (HR 0.624; 95% CI 0.406 to 0.960; P = 0.031), ferritin (HR 0.089; 95% CI 0.010 to 0.750; P = 0.026), IL − 6 (HR 0.494; 95% CI 0.264 to 0.930; P = 0.028) and myoglobin (HR 0.520; 95% CI 0.303 to 0.890; P = 0.017) had better OS than patients with abnormal levels of these laboratory indicators in the multivariate models.

Additional file 2. Supplementary material 1: Converged multivariate Cox regression model including 5 potential prognostic laboratory indicators with significance in univariate analysis (remove missing values). In the cohort where missing values were removed, only the regression models, respectively, including AST, ALT, ferritin, D-dimer and PLT were converged (due to the uneven distribution of some variables level and events number when removing missing values), suggesting that CEA was an independent prognostic factor in all multivariate models and both normal PLT (HR = 0.635, 95% CI (0.408 to 0.990), P = 0.045) and normal ferritin (HR = 0.094, 95% CI (0.010 to 0.860), P = 0.037) were also independent favorable factors compared abnormal levels.

The engine performance test was carried out on the high-performance test bench of opposed-piston engine of UAV (unmanned aerial vehicle) from 0m to 7000m altitudes. The influence of altitudes on power, torque, fuel consumption, and heat balance (cylinder surface temperature and heat flow distribution) of the engine were analyzed. The results showed that power and torque of the engine gradually decrease with the altitudes increasing. The power and torque were reduced by about 11.25% and 12.5% respectively, and the fuel consumption rate increased by 14.4% and 2.8% respectively at low-speed and high-speed with altitude rises 1000m. At the altitude of 0-3000m, the temperature and the surface temperature of the cylinder surface decreased by 18.7 and 7.9 degrees respectively with altitude of sea level per 1000m. At the altitude of 3000m-7000m, the temperature and the surface temperature of the cylinder surface decreased by 31.9 and 21.2. The outlet temperature of cooling water increased first and then decreased with altitudes increasing, and the extent of variation at high-speeds was greater than that at low-speeds. The effective thermal efficiency of the engine is less than 5%, while the percentage of lost heat is over 30% under 3000rpm speed at the altitude of 6000m.

A series of experiments were designed in order to directly heat the billet of 42CrMo4 to the forming temperature in the dies prior to forming and continue to heat the billet during the forming process. Processing parameters during heating and forming were investigated by experimental method and thermo-electro-mechanical coupling FEM. The experimental results show that prior to forming the billet could be rapidly heated to forming temperature under relatively low initial contact pressure, and the heating temperature was proportional to the square of the current intensity. When the heating current remained constant, the heating temperature could not increase with heating time. During the forming process, the billet cooling rate slowed down and the forming time was extended due to the continuous resistance heating during forming. Finally, an incrementally coupled thermo-electro-mechanical model has been developed to analyze the hot-forging process by direct resistance heating. To obtain the transient temperature field prior to forming, a simple model of contact resistance was used in the thermal-electrical simulation, in which the electrical conductance of the contact resistance was proportional to the heating temperature. Contrasted the experimental results and the simulation results, it was found that they coincided well.

Background: To analyze the relative expression of PELI3 and its mechanistic involvement in the non-small cell lung cancer (NSCLC). Methods: PELI3 expression in NSCLC tissue samples was determined by the immunohistochemistry. The transcripts abundance of PELI3 was measured with real-time PCR. The protein intensity was analyzed by western blot. The overall survival in respect to PELI3 or miR-365a-5p expression was plotted by the Kaplan–Meier's analysis. Cell growth was determined by colony formation assay. Cell viability was measured by MTT assay. The migration and invasion were evaluated by wound healing and transwell assay respectively. The regulatory effect of miR-365a-5p on PELI3 was interrogated with luciferase reporter assay. The direct binding between miR-365a-5p and PELI3 was analyzed by pulldown assay. Results: PELI3 was aberrantly up-regulated in NSCLC both in vivo and in vitro. High level of PELI3 associated with poor prognosis. PELI3-deficiency significantly inhibited cell viability, colony formation, migration and invasion. We further identified that miR-365a-5p negatively regulated PELI3 in this disease. Ectopic expression of miR-365a-5p in both A549 and H1299 phenocopied PELI3-deficiency. Meanwhile, PELI3-silencing significantly abolished the pro-tumoral effect elicited by miR-365a-5p inhibition. Conclusion: Our results highlighted the importance of dysregulated miR-365a-5p-PELI3 signaling axis in NSCLC.

Summary For a carbonate reservoir that has low porosity, its validity cannot simply be measured by its total porosity. Therefore, one must find more-effective porosity parameters to indicate reservoir validity. Two parameters that reflect the porosity spectrum's shape are proposed in this paper to characterize the porosity structure from borehole electrical images. One is the length of the right-porosity spectrum (LRPS), and the other is the root mean square (RMS) of the right-porosity spectrum (RMSRPS). Subsequently, the validity of a carbonate reservoir was considered by use of these two parameters. The logging evaluation, processing, and interpretation of multiple wells in a fractured/vuggy reservoir with low porosity in the Tarim Basin indicate that these two parameters reflect the variation of pore structures better than conventional methods, and they agree better with the well-test results.

People commute on daily basis and spend a considerable amount of time on road travels. Unfortunately, due to the dense population and concentration of economic activities in metropolitan areas, urban transportation suffers a lot of challenges, e.g. traffic congestion and parking space storage, which also affect each individual's travel experience. Previous studies have looked into the transportation condition sensing solution using various static or mobile sensors and traffic related recommendation services based on the sensing results, e.g. vehicle routing and parking recommendation. However, human behaviors as the most direct reflection as well as the final modifier of the traffic condition, have not been fully explored to close the sensing-and-control loop in the urban transportation system. This dissertation aims at improving drivers' road travel experience by taking human driver's behavior in vehicle routing and parking search processes into consideration. In the first part of the dissertation, we focus on the traffic condition sensing and routing service design, altering the isolated traffic sensing and the greedy routing strategy based on sensed traffic condition. Instead, we present a participatory system, called Themis, to consider traffic sensing and route planning as a whole: (i) By analyzing time-stamped position reports and route decisions collected from the Themis mobile app, the Themis server estimates both the current traffic rhythm and the future traffic distribution. (ii) The routing requests are then combined with the sensed traffic condition to provide route recommendations that minimize the travel cost of all drivers to proactively alleviate traffic congestions. Themis has been implemented and its performance has been evaluated in both simulation experiments using real data from over 26,000 taxis and a field study. Results from both experiments demonstrate that Themis reduces traffic congestion and average travel time at various traffic densities and system penetration rates. In the second part of the dissertation, we look into the crucial part of parking recommendation, i.e., fine-grained parking availability crowdsourcing and propose a solution based on human's parking and ignoring decisions: a parking decision immediately take an available spot while an ignored spot along a driver's parking search trajectory is likely to be already taken. However, complications caused by drivers' preferences, e.g. ignoring the spots too far from the driver's destination, have to be addressed based on human parking decisions. We build a model based on a dataset of more than 55,000 real parking decisions to predict the probability that a driver would take a spot, assuming the spot is available.Then, we present a crowdsourcing system, called ParkScan, which leverages the learned parking decision model in collaboration with the hidden Markov model to estimate background parking spot availability. ParkScan has been evaluated using real-world data from both off-street scenarios (i.e., two public parking lots) and an on-street parking scenario (i.e., 35 urban blocks in Seattle). Both of the experiments show that ParkScan reduces the error of spot-level parking availability estimation compared to the state-of-art solutions. In particular, ParkScan cuts down over 15% of the estimation errors for the spots along parking search trajectory even if there is a single participant driver.

The solubilities of o -xylene, m -xylene, and p -xylene in mixed solvents of t -butyl alcohol (TBA) and water at T =(283.15, 288.15, 293.15, and 298.15) K have been determined by spectrophotometry. The mole fractions of TBA in the mixed solvents are x =(0.000, 0.010, 0.020, 0.030, 0.040, 0.045, 0.050, 0.060, 0.080 and 0.100), respectively. The Gibbs energies of hydrophobic interaction (HI) for the aggregating process of two methane molecules with one benzene molecule in the mixed solvents have been studied, and the effects of solvent structure and solutes gathering state on the strength of HI have also been discussed.

High-altitude calibration of CA6DL2-35E3R common rail diesel engine was finished on engine high altitude simulating environment test bed. The interactions between injection parameters and its impact on engine high altitude performance were studied. Results show that the fuel delivery per cycle per cylinder increases with the adwance of injection timing and the increase of common rail pressure at the calibration sweep as a whole; fuel delivery per cycle per cylinder increased about 0.1–0.3 mg with advancing 1 ° CA injection timing and it would increase 0.07–0.1 mg with increasing 1 MPa common rail pressure averagely. The fitting error of constructed radial-based function neural network model was below 10−12 and the predictive error of which was between 1.5%, which can fulfill common rail diesel engine characteristics modeling demand. The model can help alleviate the influence of the injection timing and common rail pressure on fuel delivery per cycle per cylinder, and achieve the impact of one single injection parameter on engine performance, which can help increase the understanding of common rail diesel engine injection characteristics.

The performance of CY4102BZLQ turbocharged diesel engine with the HP60 turbocharger at different high altitudes was studied on the engine test bed for simulating high altitude (low air pressure). The conclusion indicated that the engine performance such as power and economy decreases with the increase of altitude, and the temperature of exhaust increases simultaneously. In addition, the rotational speed of the turbocharger and turbocharger ratio increase with the increase of altitude.

In order to improve the plateau adaptability of CY4102BZLQ-A2A turbocharged diesel engine, the matching performances of the diesel engine with TB28 and HP60 turbochargers at different altitudes (0 m, 2,000 m, 3,000 m, 3,500 m, 4,000 m) were investigated on the engine test bed for simulating high altitude (1ow atmosphere pressure). Results show that HP 60 turbocharger is more suitable to match the engine in terms of engine performance, intake air characteristics, turbocharger rotational speed etc. TB28 turbocharger is over speed when the engine runs at 3,500 m altitude and 2,600 r/min rotational speed, while HP60 turbocharger is over speed when the engine runs at 4,000 m altitude and 2,800 r/min rotational speed. No matter which turbocharger is selected to match the engine, the performance of the engine will deteriorate at different extents. The intake air flow mass and the air-fuel ratio decrease by 7.1-10.5% and 7.2-10.3% respectively with altitude increasing every 1,000 m. By contrast with 0 m altitude, engine torque and power at 4,000 m altitude decrease within 1% and the specific fuel consumption increases by 3.2-3.5% at the maximum torque speed, while the engine torque and power decrease by 4.6-5.3% and 4.5-5.2% respectively and the specific fuel consumption increases by 5.3-11.5% at higher and lower engine rotational speed.

Stresses and deformation are important parameters in the vacuum glazing design. Since the symmetry of the vacuum glazing, the unit cell finite element model was established. Stresses and strain of the glazing and the supports was calculated. Maximum contact stress and tensile stress of flat glass occur at the contact areas. Maximum vertical deformation of the unit occurs at the center. The stress of support is not evenly distributed, but increases with the radius of support.