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In actual production,the key components of the suspension such as the stabilizer bar,the rubber bushing and the spring are unstable due to the unstable manufacturing process,which greatly affects the vehicles’ smoothness and stability. In this paper,the McPherson front suspension is used as the research carrier,the stiffness characteristics of the components are taken as the noise variable,the hard point coordinate value is taken as the design variable,and the high-precision approximate model is established by the quadratic response surface method. Based on the same constraints, the sequence quadratic optimization algorithm is used to deterministic optimize of the suspension and the robustness design of it. The Monte Carlo simulation is used to analyze the robustness of each optimization result. The results show that the 6σ-based robustness optimization design not only optimizes the performance of the suspension but also has an advantage in terms of reliability.

A lightweight design method based on the idea of secondary optimization was proposed for a certain commercial vehicle front axle.The finite element model of the front axle was established and simulated.Combined with the fatigue endurance test,the true load of the front axle was investigated to verify the accuracy of the finite element model.The static tensile load and bending fatigue test of the real material of the front axle are taken as the light weight reference for obtaining the mechanical performance index of the front axle material after heat treatment.The overall model of the front axle is optimized and secondary optimization based on the mechanical model to ensure that the structure of the front axle meets the requirements of strength,stiffness and service life while achieving a lightweight design.The final total mass reduced 5.7 kg,to achieve the purpose of lightweight design.

To optimize and improve the impact performance of a hydraulic rock drill, it is helpful to test the stress waves of the drill and analyze the impact energy, impact frequency, and energy utilization rate. For this study, a stress wave test bench was designed and built, according to international standards, in order to study the impact process of a hydraulic rock drill under the working pressures of 18 MPa and 23 MPa. The impact energy, impact frequency, and energy utilization rate of two different hydraulic rock drill pistons in low, middle, and high gear were analyzed using a control variable method. The results demonstrate that the impact stress waves of the rock drill periodically occur in the drill rod, and then decay exponentially until they become close to zero. Moreover, the amplitude of the incident stress wave determines the rock-breaking ability of the drill. The impact energy of the short piston is greater than that of the long piston, with a maximum average value of 346.1 J; the impact frequency of the long piston is higher than that of the short piston, with a maximum average value of 62 Hz; and the energy utilization rate of the short piston is higher than that of the long piston, with a maximum average value of 56.92%, which is close to the theoretical ideal efficiency. Therefore, it can be concluded that the impact performance of a hydraulic rock drill can be effectively tested using the proposed horizontal bench, and that piston characteristics and the working pressure are the main factors affecting impact performance. Accordingly, when developing a hydraulic rock drill, it is advisable to select a shorter piston and a higher working pressure, thus allowing the drill to provide good impact performance. [ABSTRACT FROM AUTHOR]

With the gradual depletion of fossil energy sources and the improvement in environmental protection attention, efficient use of energy and reduction in carbon emissions have become urgent issues. The integrated electricity and heating energy system (IEHS) is a significant solution to reduce the proportion of fossil fuel and carbon emissions. In this paper, a stochastic optimization model of the IEHS considering the uncertainty of wind power (WP) output and carbon capture power plants (CCPs) is proposed. The WP output in the IEHS is represented by stochastic scenarios, and the scenarios are reduced by fast scenario reduction to obtain typical scenarios. Then, the conventional thermal power plants are modified with CCPs, and the CCPs are equipped with flue gas bypass systems and solution storage to form the integrated and flexible operation mode of CCPs. Furthermore, based on the different load demand responses (DRs) in the IEHS, the optimization model of the IEHS with a CCP is constructed. Finally, the results show that with the proposed optimization model and shunt-type CCP, the integrated operation approach allows for a better reduction in carbon capture costs and carbon emissions. [ABSTRACT FROM AUTHOR]

The enhancement of the breakdown power during the spark discharge process has been proved to be beneficial for the flame kernel formation process under lean/diluted conditions. Such a strategy is realized by using a conventional transistor coil ignition system with an add-on capacitance in parallel to the spark plug gap in this paper. In practical application, the use of different ceramic material other than aluminum oxide can change the parasitic capacitance of the spark plug, achieving similar effect in terms of rescheduling the discharge energy released during the breakdown phase. Detailed research has been carried out to investigate the effect of the parallel capacitance and the cross flow velocity on the flame kernel formation and propagation process. With the increase in parallel capacitance, more spark energy is delivered during the breakdown phase, while less energy is released during the arc/glow phase. Shadowgraph images of the spark plasma reveal that the high-power spark discharge can generate a larger high-temperature area with enhanced electrically prompted turbulence under quiescent conditions, as compared with that using the conventional transistor coil ignition discharge strategy under the same condition. The breakdown enhanced turbulence of the high-power spark is proved to be beneficial for the flame kernel development, especially with the lean or exhaust gas recirculation diluted combustible mixtures, given that sufficient spark energy is available for the high-power spark strategy to successfully generate the breakdown event. The results of combustion tests under flow conditions reveal that the breakdown enhanced turbulence of the high-power spark tends to be overshadowed by the turbulence generated from the flow field, and both the increase in flow velocity and parallel capacitance contribute to the reduction in discharge duration of the arc/glow phase. Therefore, the benefits brought about by the high-power spark discharge tend to diminish with the intensification of flow velocity. [ABSTRACT FROM AUTHOR]

Bone metastasis caused by breast cancer leads to significant complications in treatment, and the resulting osteolysis considerably affects patients' overall survival and quality of life. Gö6983 is a broad spectrum protein kinase C inhibitor. In this study, based on our finding that the Gö6983 inhibits osteolysis, we applied Gö6983 to the MDA‐MB‐231 breast cancer‐induced mouse bone metastasis model. And we found that Gö6983 has a strong inhibitory effect on the tumorigenic model of breast cancer by promoting the mitochondrial apoptosis pathway. Our study, therefore, demonstrates that Gö6983 has a potential inhibitory effect on breast cancer‐induced osteoclast activation and provides mechanistic insight that may prove useful for designing future treatments. [ABSTRACT FROM AUTHOR]

Spark discharge under flow conditions in different gas media is compared. The gases include nitrogen, pure methane, and methane–air mixtures with different volume ratios. The self-illuminated spark plasma photos, and the discharge current and voltage waveforms are recorded. [ABSTRACT FROM AUTHOR]

Chelating 1,2,3-triazole-4-carboxylic acids were successfully introduced onto the cross-linked PGMA microsphere surfaces by the combination of ring-opening reactions and the click chemistry process between the alkynyl groups of propiolic acid (PA) and the epoxy groups on the surfaces of the PGMA microspheres. The resultant PA-conjugated PGMA microspheres were found to be an effective adsorbent for Pb(ii) removal from aqueous solutions. Success in each functionalization step was ascertained by ATR-FTIR, XPS and SEM characterization. Batch and column adsorption experiments were performed to determine the adsorption kinetics, adsorption isotherms and thermodynamics of Pb(ii) ions on the as-synthesized microspheres. The Langmuir-fitted maximum adsorption capacity for Pb(ii) ions was found to be 69.41 mg g−1 at a solution pH of 5.0, together with the adsorption equilibrium being achieved within 60 min. The thermodynamic studies demonstrated an endothermic and spontaneous adsorption process of Pb(ii) ions on the PA-conjugated PGMA microspheres. Column adsorption studies revealed the decrease in the adsorption capacities of the breakthrough and exhaustion points with increasing flow rate. The postulated adsorption mechanism was attributed to the electrostatic interactions from carboxylic groups and chelation or coordination of Pb(ii) ions from the triazole moieties, which was facilitated to form a pluralistic potential trap for Pb(ii) ions, as confirmed by XPS characterization. [ABSTRACT FROM AUTHOR]

Engine tests were conducted to investigate the efficiency and the peak pressure rise rate performance of different fuel injection strategies for the direct injection of neat n-butanol in a compression ignition engine. Three different strategies were tested: a single-shot injection; a pilot injection; a post-injection. A single-shot injection timing sweep revealed that early injections had the highest indicated efficiency while late injections reduced the peak pressure rise rate at the cost of a slightly reduced thermal efficiency. Delayed single-shot injections also had increased emissions of nitrogen oxides, total hydrocarbon and carbon monoxide. Addition of a pilot injection had a negative effect on the peak pressure rise rate. Because of the low cetane number of butanol and the relatively lean and well-premixed air–fuel mixture, the pilot injection failed to autoignite and instead ignited simultaneously with the main injection. This resulted in slightly increased peak pressure rise rates and significantly increased unburned butanol hydrocarbon emissions. Conversely, the use of an early post-injection produced a noticeable engine power output and allowed the main injection to be shortened and the peak pressure rise rate to be substantially reduced. However, relatively early post-injections slightly reduced the indicated efficiency and increased the nitrogen oxide emissions and the carbon monoxide emissions compared with the single-shot injection strategy. These results recommended the use of a single-shot injection for low loads and medium loads owing to a superior thermal efficiency and suggested that the application of a post-injection may be more suited to high-load conditions because of the substantially reduced peak pressure rise rates. [ABSTRACT FROM AUTHOR]

Characterized by its customary symbol system and simple and vivid expression patterns, cyber language acts as not only a tool for convenient communication but also a carrier of abundant emotions and causes high attention in public opinion analysis, internet marketing, service feedback monitoring, and social emergency management. Based on our multidisciplinary research, this paper presents a classification of the emotional symbols in cyber language, analyzes the cognitive characteristics of different symbols, and puts forward a mechanism model to show the dominant neural activities in that process. Through the comparative study of Chinese, English, and Spanish, which are used by the largest population in the world, this paper discusses the expressive patterns of emotions in international cyber languages and proposes an intelligent method for affective computing on cyber language in a unified PAD (Pleasure-Arousal-Dominance) emotional space. [ABSTRACT FROM AUTHOR]

This paper proposed an analytical model on the deterioration of magnetic sensitivity of sectorial split-drain magnetic field-effect transistors (SD-MAGFETs). The deterioration is governed by the trap fill rate at the channel boundary traps, which is geometric dependent. Experimental results are presented which show good consistency with the analytical derivation. The deterioration is the most severe at a sector angle of 54.6^\circ, which shows a design tradeoff with sensing hysteresis. Design guidelines for sectorial SD-MAGFET to obtain high sensitivity hysteresis and slow sensitivity deterioration are also presented which provide important information for efficient design. [ABSTRACT FROM PUBLISHER]

This paper proposed an analytical model on the geometric dependence of the transient sensitivity and transient sensing hysteresis of sectorial split-drain magnetic field-effect transistors (SD-MAGFETs). We also conjectured that the transient sensing hysteresis is caused by the charge trapped on channel boundary, and is also geometric dependent. Experimental results are presented which show good consistence with the analytical derivation. The derived analytical model and experimental results can be used as a design guideline for the optimization and trade-off of the transient sensitivity and transient sensing hysteresis of the sectorial SD-MAGFETs. [ABSTRACT FROM AUTHOR]

The relationships between above-ground stem, branch, leaf masses and stand density index (SDI) were analysed in Populus × euramericana (Dode) Guinier stands in Jiangsu Province, China. The allometric equations developed in this study accurately estimated masses of above-ground and specific above-ground tree components in stands with different SDIs. The relationship between the mean above-ground mass w and the ratio of stem to the above-ground (wS/w) was examined. With increasing w, the stem mass ratio wS/w increased. Mean masses of above-ground and tree components decreased significantly with increasing SDI at age 9 years, indicating the presence of competition-induced limitations to growth. The mean above-ground mass–SDI and mean component mass–SDI were strongly correlated with above-ground mass-SDI and tree component mass–SDI, respectively. An equation describing the relationship between the mean leaf area u and SDI was developed, which fitted well for the u-SDI data. Stem mass increment exponentially increased with increasing leaf area index. [ABSTRACT FROM PUBLISHER]

A belt of khondalite-series rocks in the Western Block of the North China craton (NCC) are considered to represent products of the collision between the north Yinshan and the south Ordos terranes before final amalgamation of the NCC basement. The Jining Complex of Inner Mongolia occurs in the eastern part of the Khondalite Belt and is crosscut by the Trans-North China Orogen. Khondalite rocks of the Jining Complex mainly comprise sillimanite-garnet gneiss, garnet/sillimanite-bearing granite, massive porphyritic granite, garnet quartzite, calc-silicate, and marble with minor felsic gneiss and mafic granulite. LA-ICP-MS, U-Pb dating and cathodoluminescence (CL) image analysis of zircons from five rocks from the complex, i.e. Sil-Bt-Grt leptynite gneiss, Spl-Sil-Ksp-Grt vein in (Crd)-Sil-Grt gneiss, Sil-Grt-K-Fsp mylonite from a shear zone, Crd-bearing Sil-Grt gneiss, and granite were used to determine protolith and metamorphic ages of the khondalite-series rocks. Results of 315 detrital zircon grains indicate five age populations: 2410-2550 Ma, 2162 Ma, 2047-2099 Ma, 1950-1993 Ma, and 1866 Ma. CL investigation reveals that zircon grains of most samples are rounded, unzoned with low Th/U, indicating a metamorphic origin, whereas quite a few grains in some rocks are characterized by magmatic oscillatory zoning and comparatively high Th/U, and are typically overgrown by metamorphic, low CL rims with low Th/U. Three samples of Sil-Bt-Grt gneiss record oldest ages of ∼2550-2480 Ma, suggesting an Archaean/early Palaeoproterozoic provenance for the Jining Complex. Ages of ∼2162-2047 Ma are interpreted as the metamorphic modified inherited source of supercrustal protoliths of the khondalite-series rocks. The khondalite depositional age is defined as 2228-2027 Ma by concordant ages obtained in this research. The Sil-Ksp-Grt vein and the granite have single population ages of 1985 ± 28 Ma and 1957 ± 19 Ma, respectively, and are inferred to record the same metamorphic event, i.e. formation of the Khondalite Belt within the Western Block owing to the collision of the north Yinshan and the south Ordos terranes. The Sil-Grt-K-Fsp mylonite yields a single group age of 1866 ± 22 Ma, which may date final suturing of the Eastern Block and the Western Block and stabilization of the NCC. [ABSTRACT FROM AUTHOR]

Synthetic aperture imaging radiometers (SAIRs) are powerful passive microwave systems for high-resolution imaging by use of synthetic aperture technique. However, the ill-posed inverse problem for SAIRs makes it difficult to reconstruct the high-precision brightness temperature map. The traditional regularization methods add a unique penalty to all the frequency bands of the solution, which may cause the reconstructed result to be too smooth to retain certain features of the original brightness temperature map such as the edge information. In this paper, a multi-parameter regularization method is proposed to reconstruct SAIR brightness temperature distribution. Different from classical single-parameter regularization, the multi-parameter regularization adds multiple different penalties which can exhibit multi-scale characteristics of the original distribution. Multiple regularization parameters are selected by use of the simplified multi-dimensional generalized cross-validation method. The experimental results show that, compared with the conventional total variation, Tikhonov, and band-limited regularization methods, the multi-parameter regularization method can retain more detailed information and better improve the accuracy of the reconstructed brightness temperature distribution, and exhibit superior noise suppression, demonstrating the effectiveness and the robustness of the proposed method. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative disease of the cartilage that is prevalent in the middle-aged and elderly demography. Polydatin (PD), a natural resveratrol glucoside, has shown significant anti-inflammatory and anti-arthritic potential in previous studies. This study was designed to evaluate the therapeutic properties of PD in vitro and in vivo, and elucidate their underlying mechanisms. The expression levels of all relevant factors were evaluated by qRT-PCR, western blotting, and immunohistochemistry (IHC) where suitable. Reactive oxygen species (ROS) and apoptosis were analyzed using the suitable probes and flow cytometry. The histological evidence of cartilage was assessed in rat models, moreover, the several serum cytokines levels and autophagy levels were evaluated. The result showed PD displayed significant chondro-protective effects, inferred in terms of reduced inflammation and cartilage degradation, apoptosis inhibition, and lower ROS production. The protective effects were attenuated by the autophagy inhibitor 3-MA, indicating a mediating role of autophagy in PD action. Mechanistically, PD exerted its effects by inhibiting the MAPK and PI3K/Akt signaling pathways which led to the down-regulation of mTOR. In conclusion, PD protects against cartilage degeneration by activating the autophagy flux in the chondrocytes via the MAPK and PI3K/Akt signaling pathways. [ABSTRACT FROM AUTHOR]

Cross-linked chitosan (CCS) microspheres tethered with melamine-conjugated poly(hydroxyethyl methacrylate) (PHEMA) brushes were synthesized by combination of surface-initiated atom transfer radical polymerization (ATRP) of HEMA and subsequent covalent immobilization of melamine onto the chain ends of PHEMA brushes. The as-synthesized CCS microsphere was used as a novel adsorbent for effective uptake of Cu(II) ions from aqueous solution. Success in each functionalization step was ascertained by SEM, ATR-FTIR and XPS characterization. Batch adsorption experimental results demonstrated that the adsorption equilibrium of Cu(II) ions on the melamine-grafted CCS microsphere was rapidly established within 20 min, and the adsorption process was found to be governed by intra-particle diffusion and chemisorption processes. The Langmuir-fitted maximum adsorption capacity of Cu(II) ions on the as-synthesized CCS microspheres was as high as circa 4.67 mmol L −1 (299 mg g −1 ). The calculated thermodynamic parameters revealed an endothermic and spontaneous adsorption process of Cu(II) ions on the melamine-grafted CCS microspheres. XPS spectra revealed that the adsorption mechanism was attributed to coordination (or chelation) interactions between amino (or hydroxyl) groups with cationic Cu(II) ions. [ABSTRACT FROM AUTHOR]

Daphnetin (DAP) is a traditional Chinese drug usually used to treat cardiovascular diseases. Studies have confirmed the anti-inflammatory, antioxidant, anti-bacterial and insecticidal, anti-tumor and neuro-protective effects of DAP. However, its anti-arthritic potential remains unexplored. The aim of this study is to investigate the in vitro and in vivo chondroprotective effects of DAP. The effect of DAP on primary rabbit chondrocytes was examined using recombinant human IL-1β for 24 h. For the in vivo studies, rabbits were randomly divided into groups: a normal control group and osteoarthritis (OA) groups. The OA groups received three different doses of DAP for 4 or 8 weeks. The anti-arthritic effect of DAP was assessed using histopathological examinations, qRT-PCR, western blotting and immunohistochemical analysis. Both in vitro and in vivo results indicate that DAP exerts a protective effect against IL-1β in chondrocytes. In vitro , DAP inhibits the expression of IL-6, IL-12, MMP-3, MMP-9 and MMP-13, induced by IL-1β in rabbit chondrocytes, and stimulates the production of IL-10. The inhibitory effect of DAP on the MMPs is partially regulated by the inhibition of the PI3K/AKT, MAPK and NF-κB signaling pathways. The effect of DAP on OA may be attributed to the suppression of inflammatory factor secretion, chondrocyte apoptosis observed by the decrease in pro-apoptotic Caspase-3 and BAX, and the activation of anti-apoptotic BCL-2. DAP has a broad range of prospects in the treatment of OA, which provides a novel therapeutic strategy for OA. [ABSTRACT FROM AUTHOR]

Background: The aim was to explore the optimal neoadjuvant therapy strategy for resectable, borderline resectable, and locally advanced pancreatic cancer, in order to provide a theoretical basis for the development of new neoadjuvant treatment protocols for clinical use., Patients and Methods: The authors reviewed literature titles and abstracts comparing three treatment strategies (neoadjuvant chemoradiotherapy, neoadjuvant chemotherapy, and upfront surgery) in PubMed, Embase, The Cochrane Library, Web of Science from 2009 to 2023 to estimate relative odds ratios for resection rate and hazard ratios (HRs) for overall survival (OS) in all include trials., Results: A total of nine studies involving 889 patients were included in the analysis. The treatment methods included upfront surgery, neoadjuvant chemotherapy, and neoadjuvant chemoradiotherapy followed by surgery. The network meta-analysis results demonstrated that neoadjuvant chemoradiotherapy followed by surgery was an effective approach in improving OS for resectable and borderline resectable pancreatic cancer (RPC) patients compared to upfront surgery (HR: 0.79, 95% CI: 0.64-0.98) and neoadjuvant chemotherapy (HR: 0.79, 95% CI: 0.64-0.98). Additionally, neoadjuvant chemoradiotherapy significantly increased the margin negative resection (R0) rate and pathological negative lymph node (pN0) rate in patients with resectable and borderline RPC. However, it is worth noting that neoadjuvant chemoradiotherapy increased the risk of grade 3 or higher treatment-related adverse events, including in patients with locally advanced pancreatic cancer., Conclusions: The current evidence suggests that neoadjuvant chemoradiotherapy followed by surgery is the optimal choice for treating patients with resectable and borderline RPC. Future research should focus on optimizing neoadjuvant chemoradiotherapy regimens to effectively improve OS while reducing the occurrence of adverse events., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: In the past decades, substantial effort has been made to explore the genetic influence on brain structural/functional abnormalities in schizophrenia, as well as cognitive impairments. In this work, we aimed to extend previous studies to explore the internal mediation pathway among genetic factor, brain features and cognitive scores in a large Chinese dataset., Methods: Gray matter (GM) volume, fractional amplitude of low-frequency fluctuations (fALFF), and 4522 schizophrenia-susceptible single nucleotide polymorphisms (SNP) from 905 Chinese subjects were jointly analyzed, to investigate the multimodal association. Based on the identified imaging-genetic pattern, correlations with cognition and mediation analysis were then conducted to reveal the potential mediation pathways., Findings: One linked imaging-genetic pattern was identified to be group discriminative, which was also associated with working memory performance. Particularly, GM reduction in thalamus, putamen and bilateral temporal gyrus in schizophrenia was associated with fALFF decrease in medial prefrontal cortex, both were also associated with genetic factors enriched in neuron development, synapse organization and axon pathways, highlighting genes including CSMD1, CNTNAP2, DCC, GABBR2 etc. This linked pattern was also replicated in an independent cohort (166 subjects), which although showed certain age and clinical differences with the discovery cohort. A further mediation analysis suggested that GM alterations significantly mediated the association from SNP to fALFF, while fALFF mediated the association from SNP and GM to working memory performance., Interpretation: This study has not only verified the impaired imaging-genetic association in schizophrenia, but also initially revealed a potential genetic-brain-cognition mediation pathway, indicating that polygenic risk factors could exert impact on phenotypic measures from brain structure to function, thus could further affect cognition in schizophrenia., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)