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A new type of disk groove mechanism was developed and manufactured. The effects of the structural and operating factors of the disk groove on the air film loading performance were examined using single factor and orthogonal experimental methods. The results of numerical simulation and experimental studies showed that the air film loading performance correlated positively with the orifice diameter and inlet pressure, with the orifice spacing and diameter having the most significant effects, and that the belt speed boosted the air film uniformity. Meanwhile, a comparative analysis of the corresponding level values showed that an air film thickness of 0.8 mm, orifice diameter of 5 mm, orifice spacing of 30 mm, inlet pressure of 8000 Pa, and conveyor speed of 5 m/s were the optimal parameter combinations for the maximum loading capacity. To verify the accuracy of the model, a field experiment was conducted at Jiangmen Southern Conveying Machinery Engineering Co., Ltd. The air film pressure at the experimental position matched the numerical simulation results. In addition, when the number of rows was one and the air volume was 10 m3/h, the smallest value of traction resistance was obtained under minimum power consumption.

With the development of comprehensive treatment, locoregional transarterial chemotherapy has become an alternative conversion therapy, palliative therapy, and neoadjuvant therapy for many solid malignant tumors. Locoregional transarterial chemotherapy, which is most frequently used for treating liver cancer, has the characteristics of high regional efficacy and few systemic adverse reactions. In recent years, the number of relevant reports of locoregional chemotherapy for treating initially inoperable colorectal cancer (CRC), including non-metastatic and metastatic CRC, has gradually increased. However, the specific treatment options for such locoregional therapy are not the same, and its indications, medication regimens and combined treatments have not reached any consensus. In this review, the application status of locoregional transarterial chemotherapy in primary and metastatic CRC patients has been reviewed and summarized to provide a reference for future clinical work and scientific research.

The advent of the digital era has transformed E-commerce platforms into critical tools for industry, yet traditional recommendation systems often fall short in the specialized context of the electric power industry. These systems typically struggle with the industry's unique challenges, such as infrequent and high-stakes transactions, prolonged decision-making processes, and sparse data. This research has developed a novel recommendation engine tailored to these specific conditions, such as to handle the low frequency and long cycle nature of Business-to-Business (B2B) transactions. This approach includes algorithmic enhancements to better process and interpret the limited data available, and data pre-processing techniques designed to enrich the sparse datasets characteristic of this industry. This research also introduces a methodological innovation that integrates multi-dimensional data, combining user E-commerce activities, product specifics, and essential non-tendering information. The proposed engine employs advanced machine learning techniques to provide more accurate and relevant recommendations. The results demonstrate a marked improvement over traditional models, offering a more robust and effective tool for facilitating B2B transactions in the electric power industry. This research not only addresses the sector's unique challenges but also provides a blueprint for adapting recommendation systems to other industries with similar B2B characteristics.

Universal access to clean fuels in household use is one explicit indicator of sustainable development while currently still billions of people rely on solid fuels for daily cooking. Despite of the recognized clean transition trend in general, disparities in household energy mix in different activities (e.g. cooking and heating) and historical trends remain to be elucidated. In this study, we revealed the historical changing trend of the disparity in household cooking and heating activities and associated carbon emissions in rural China. The study found that the poor had higher total direct energy consumption but used less modern energy, especially in cooking activities, in which the poor consumed 60 % more energy than the rich. The disparity in modern household energy use decreased over time, but conversely the disparity in total residential energy consumption increased due to the different energy elasticities as income increases. Though per-capita household CO2 and Black Carbon (BC) emissions were decreasing under switching to modern energies, the disparity in household CO2 and BC deepened over time, and the low-income groups emitted ∼ 10 kg CO2 more compared to the high-income population. Relying solely on spontaneous clean cooking transition had limited impacts in reducing disparities in household energy and carbon emissions, whereas improving access to modern energy had substantial potential to reduce energy consumption and carbon emissions and its disparity. Differentiated energy-related policies to promote high-efficiency modern heating energies affordable for the low-income population should be developed to reduce the disparity, and consequently benefit human health and climate change equally.

Wear-resistant steel/carbon steel composite plates not only have the double performance advantages of high strength and wear resistance but can also reduce energy consumption and production costs. Based on a 50% reduction rate, the wear resistance of the BTW1/Q345 composite was studied at different annealing temperatures, and the dry friction and wear tests of the BTW1/Q345 composite at different annealing temperatures were carried out using RETC MFT-5000. By using the white-light interference three-dimensional surface profiler, scanning electron microscope (SEM), and backscattered electron diffraction (EBSD) technology, we carried out a detailed analysis of the macroscopic and microscopic morphology and wear mechanism of wear traces at different annealing temperatures. The effects of the annealing process on the thickness and composition of the wear layer were studied, and the causes of wear failure were analyzed based on the results of scanning electron microscopy. It was found that as the annealing temperature gradually increased, the particle size near the scratch of BTW1 in the wear-resistant layer of the composite plate became smaller. On this basis, the effects of different annealing temperatures on the friction and wear characteristics of the composite plate were further studied. At the annealing temperature of 860 ° C, the wear resistance of the material was the best.

The association between sarcopenia and the effectiveness of neoadjuvant chemotherapy (NAC) in triple-negative breast cancer (TNBC) remains uncertain. This study aims to examine the potential of sarcopenia as a predictive factor for the response to NAC in TNBC, and to assess whether its combination with MRI radiomic signatures can improve the predictive accuracy. We collected clinical and pathological information, as well as pretreatment breast MRI and abdominal CT images, of 121 patients with TNBC who underwent NAC at our hospital between January 2012 and September 2021. The presence of pretreatment sarcopenia was assessed using the L3 skeletal muscle index. Clinical models were constructed based on independent risk factors identified by univariate regression analysis. Radiomics data were extracted on breast MRI images and the radiomics prediction models were constructed. We integrated independent risk factors and radiomic features to build the combined models. The results of this study demonstrated that sarcopenia is an independent predictive factor for NAC efficacy in TNBC. The combination of sarcopenia and MRI radiomic signatures can further improve predictive performance.

Purposes In order to meet the requirements of lightweight design of large mining dump truck carriage, the rib layout is optimized on the basis of bionic structure. Methods The basic structure and functional characteristics of a mining dump truck are introduced. The load-bearing characteristics of the carriage under various working conditions are analyzed, and the carriage with full loads and uniform speed or static state is selected as the limit working condition for the bottom plate. The rigidity and strength are studied through simulation analysis. The morphological characteristics of vein branching structure are summarized, and the high similarity between vein branching structure and bottom plate of the carriage is expounded from three aspects of load, structure, and function. A new rib layout and a new carriage are designed according to the morphological characteristics. The mechanical performances of the new carriage are verified through Finite Element Analysis. Conclusion The results show that the load-bearing performance of the new carriage is better, the stress distribution is more uniform, and the load borne by the bottom plate is transferred to the lower rib plates, effectively reducing the bearing capacity of the main beam. Its stiffness and strength are increased by 20.32% and 32.37% respectively, while the weight is reduced by 1.86%.

Acute myeloid leukemia (AML) is a malignant disease of myeloid hematopoietic stem/progenitor cells characterized by the abnormal proliferation of primitive and naive random cells in the bone marrow and peripheral blood. Acute promyelocytic leukemia (APL) is a type (AML-M3) of AML. Most patients with APL have the characteristic chromosomal translocation t(15; 17)(q22; q12), forming PML::RARA fusion. The occurrence and progression of AML are often accompanied by the emergence of gene fusions such as PML::RARA, CBFβ::MYH11, and RUNX1::RUNX1T1, among others. Gene fusions are the main molecular biological abnormalities in acute leukemia, and all fusion genes act as crucial oncogenic factors in leukemia. Herein, we report the first case of LYN::LINC01900 fusion transcript in AML with a promyelocytic phenotype and TP53 mutation. Further studies should address whether new protein products may result from this fusion, as well as the biological function of these new products in disease occurrence and progression.

Abstract Following a series of actions in China, the annual mean fine particle (PM2.5) concentrations have considerably reduced since 2013. However, in some cities, the PM2.5 concentrations exceed the national ambient air quality standard of 35 μg/m3. Herein, we evaluated the historical trends of PM2.5 from 2014 to 2022 in mainland China and found continuously declining trends. However, the annual decline rates decreased despite increasing investments on pollution control, showing considerably diminishing marginal effects of these investments. Accumulative reduction in PM2.5 concentrations is linearly dependent on the log‐transformed accumulative investment in air pollution control. The standard of 35 μg/m3 can be achieved by 2035 if the current efforts continue at the same pace. However, the standard of 35 μg/m3 can weaken the momentum of future actions in cities where the standard has already been implemented. We proposed and tested two tiers with four or six levels of specific regional standards based on the regression model predictions from the historical data and demonstrated that more rigorous standards for regions where the current standard is already attained could provide more momentum for strengthening abatement efforts. The results show that both tiers are feasible if the level of abatement endeavor is maintained even with marginal effects. We also demonstrate that additional 135,000 or 384,000 deaths can be avoided by applying the regional standards. Health benefits are monetized and compared with the control costs, suggesting that compared to Tier‐2, Tier‐1 is more cost‐effective and balanced across the mainland China.

Abstract Background Laryngeal mask airways have been widely used in clinical practice. The aim of this study was to investigate whether the remifentanil requirement for facilitation of i-gel insertion in Parkinson’s disease (PD) patients undergoing deep brain stimulation (DBS) surgery was different from that in non-PD (NPD) patients undergoing intracranial surgery. Study design An up-and-down sequential allocation trial. Methods Male patients aged between 40 and 64 years old were enrolled. The first patient in each group (PD and NPD) group received an effect-site concentration (Ce) of remifentanil (Minto pharmacokinetic model) of 4.0 ng.ml−1 during a target-controlled infusion (TCI) of 3.5 μg.ml−1 propofol (Marsh pharmacokinetic model). The next dose of remifentanil was determined by the response of the previous patient. The Ce of remifentanil required for i-gel insertion in 50% of patients (EC50) was estimated by the modified Dixon’s up-and-down method and by probit analysis. Results The PD group included 24 patients and the NPD group included 23. The EC50 of remifentanil for i-gel insertion during a TCI of 3.5 μg.ml−1 propofol estimated by the modified Dixon’s up-and-down method in PD patients (2.38 ± 0.65 ng.ml−1) was significantly lower than in NPD patients (3.21 ± 0.49 ng.ml−1) (P = 0.03). From the probit analysis, the EC50 and EC95 (effective Ce in 95% of patients) of remifentanil were 1.95 (95% CI 1.52–2.36) ng.ml−1 and 3.12 (95% CI 2.53–5.84) ng.ml−1 in PD patients and 2.85 (95% CI 2.26–3.41) ng.ml−1 and 4.57 (95% CI 3.72–8.54) ng.ml−1 in NPD patients, respectively. Conclusions The remifentanil requirement for successful i-gel insertion is reduced in male PD patients undergoing DBS implantation during propofol TCI induction. Clinicians should closely monitor the remifentanil requirement in patients with PD. Trial registration Registered at http://www.chictr.org.cn ( ChiCTR1900021760 ).

Background and objectivePreoperative transcatheter rectal arterial chemoembolization (TRACE) can enhance the pathological response rate in some patients with locally advanced rectal cancer (LARC). However, how to accurately identify patients who can benefit from this neoadjuvant modality therapy remains to be further studied. Deficient mismatch repair (dMMR) protein plays a crucial role in maintaining genome stability. A proportion of patients with rectal cancer are caused by the loss of mismatch repair (MMR) protein. Given the role of MMR in guiding the efficacy in patients with colorectal carcinoma (CRC), this study is designed to evaluate the effect of dMMR status on the response to neoadjuvant therapy through a retrospective analysis.MethodsWe launched a retrospective study. First, we selected patients with LARC from the database, and these patients had received preoperative TRACE combined with concurrent chemoradiotherapy. Then, the tumor tissue biopsied by colonoscopy before intervention was taken for immunohistochemistry. According to the expression of MLH-1, MSH-2, MSH-6 and PMS-2, these patients were divided into dMMR protein group and proficient MMR (pMMR) protein group. All patients underwent pathological examination at the end of neoadjuvant therapy, either surgically excised tissue or colonoscopically biopsied tissue. The end point was the pathologic complete response (pCR) after TRACE combined with concurrent chemoradiotherapy.ResultsFrom January 2013 to January 2021, a total of 82 patients with LARC received preoperative TRACE combined with concurrent chemoradiotherapy, and the treatment was well tolerated. Among 82 patients, there were 42 patients in the pMMR group and 40 patients in the dMMR group. 69 patients returned to the hospital for radical resection. In 8 patients, the colonoscopy showed good tumor regression grade after 4 weeks of interventional therapy and refused surgery. The remaining five patients were neither surgically treated nor reexamined by colonoscopy. 77 patients were eventually enrolled in the study. Individually, the pCR rates of these two groups (10%, 4/40 vs. 43%, 16/37) showed significant difference (P < 0.05). Biomarker analysis indicated that patients with dMMR protein had a better propensity for pCR.ConclusionIn patients with LARC, preoperative TRACE combined with concurrent chemoradiotherapy showed good pCR rates, especially in patients with dMMR. Patients with MMR protein defects have a better propensity for pCR.

Abstract Background Previous studies have shown that women achieve a better quality of postoperative recovery from total intravenous anesthesia (TIVA) than from inhalation anesthesia, but the effect of anesthesia type on recovery in male patients is unclear. This study therefore compared patient recovery between males undergoing lumbar surgery who received TIVA and those who received sevoflurane anesthesia. Methods Eighty male patients undergoing elective one- or two-level primary transforaminal lumbar interbody fusion (TLIF) were randomly divided into two groups: the TIVA group (maintenance was achieved with propofol and remifentanil) or sevoflurane group (SEVO group: maintenance was achieved with sevoflurane and remifentanil). The quality of recovery-40 questionnaire (QoR-40) was administered before surgery and on postoperative days 1 and 2 (POD1 and POD2). Pain scores, postoperative nausea and vomiting, postoperative hospital stay, anesthesia consumption, and adverse effects were recorded. Results The QoR-40 scores were similar on the three points (Preoperative, POD1 and POD2). Pain scores were significantly lower in the SEVO group than in the TIVA group on POD1 (30.6 vs 31.4; P = 0.01) and POD2 (32 vs 33; P = 0.002). There was no significant difference in the postoperative hospital stay or complications in the postanesthesia care unit between the TIVA group and the SEVO group. Conclusions This study demonstrates that the quality of recovery is not significantly different between male TLIF surgery patients who receive TIVA and those who receive sevoflurane anesthesia. Patients in the TIVA group had better postoperative analgesic effect on POD2. Trial registration This was registered at http://www.chictr.org.cn (registration number ChiCTR-IOR-16007987, registration date: 24/02/2016).

The society has high concerns on the inequality that people are disproportionately exposed to ambient air pollution, but with more time spent indoors, the disparity in the total exposure considering both indoor and outdoor exposure has not been explored; and with the socioeconomical development and efforts in fighting against air pollution, it is unknown how the exposure inequality changed over time. Based on the city-level panel data, this study revealed the Concentration Index (C) in ambient PM2.5 exposure inequality was positive, indicating the low-income group exposed to lower ambient PM2.5; however, the total PM2.5 exposure was negatively correlated with the income, showing a negative C value. The low-income population exposed to high PM2.5 associated with larger contributions of indoor exposure from the residential emissions. The total PM2.5 exposure caused 1.13 (0.63–1.73) million premature deaths in 2019, with only 14 % were high-income population. The toughest-ever air pollution countermeasures have reduced ambient PM2.5 exposures effectively that, however, benefited the rich population more than the others. The transition to clean household energy sources significantly affected on indoor air quality improvements, as well as alleviation of ambient air pollution, resulting in notable reductions of the total PM2.5 exposure and especially benefiting the low-income groups. The negative C values decreased from 2000 to 2019, indicating a significantly reducing trend in the total PM2.5 exposure inequality over time.

The power loss generated by the air cushion belt conveyor when transporting materials mainly depends on the diameter of the orifice, the form of arrangement, and the thickness of the air film. A mathematical model of an air cushion belt conveyor is established through mechanical analysis, and the relationship between load distribution, air film thickness, air film carrying capacity, and power consumption is found. Numerical simulations of orifices of different diameters on the disk groove and the formed air film are carried out, and the loading capacity of the air film was analyzed by observing the stress and deformation of the wire rope core. The results show that the air film formed by the selected type of orifice arrangement in this paper carries the load, which causes the least amount of deformation and stress change in the wire rope core, and the stability of the air film loading capacity is also verified by experiments.

Adults with bowel intussusception caused by malignant tumors are fairly uncommon. We presented a case of a 64-year-old woman whose intussusception was secondary to ascending colon cancer. A color Doppler ultrasonography of the abdomen revealed a low echo mass in the right middle abdomen. Physical examination and digital rectal examination were both unremarkable. Computed tomography (CT) revealed a concentric circle change in the colon, as well as the mesenterium and arteries. Electronic colonoscopy discovered the colonic giant proliferative lesions and stenosis. Adenocarcinoma with moderate differentiation was discovered after a biopsy. Then laparotomy showed intussusception and the tumor was located in the ascending colon. The postoperative pathological test revealed moderately differentiated adenocarcinoma in the right colon invaded the whole layer. After hospitalization, the patient was discharged without any complications. This case highlights that rational use of CT, endoscopy, and timely surgery combines an effective strategy for the treatment of adult intussusception.

Background: Bladder cancer (BCa), among the world’s most common malignant tumors in the urinary system, has a high morbidity and mortality. Though cuproptosis is a new type of cell death mediated by lipoylated tricarboxylic acid (TCA) cycle proteins, the role of cuproptosis-related long noncoding RNAs (crlncRNAs) in bladder tumors awaits further elucidation. In this paper, we tried to explore how important crlncRNAs are for BCa.Methods: The crlncRNAs were first obtained through Pearson correlation analysis of the RNA-seq data and corresponding clinical data downloaded from The Cancer Genome Atlas (TCGA). Then, three lncRNAs were acquired by Cox regression and Lasso regression to build a prognostic model of crlncRNAs for verification. In the meantime, clinicopathological correlation analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, principal component analysis (PCA), immunoassay, and half-maximal inhibitory concentration prediction (IC50) were carried out. Then, an entire tumor was classified into two clusters by crlncRNA expression to further discuss the differences in prognosis, immune status and drug susceptibility among different subgroups.Results: We obtained a total of 152 crlncRNAs and built a risk model for screened crlncRNAs. We validated the model and found that calibration charts feature a high consistency in verifying nomogram prediction. Receiver operating characteristic (ROC) curve and univariate and multivariate Cox regression suggested that this model can be applied as an independent prognostic factor of bladder cancer due to its high accuracy. According to KEGG analysis, high-risk groups were enriched in cancer and immune-related pathways. During tumor immunoassay, noticeable differences were observed in both immune infiltration and checkpoints between high- and low-risk patients. Of the two subgroups divided among patients by consensus clustering, cluster 2 had a better prognosis, whereas cluster 1 had higher immunoreactivity scores, more immune cell infiltrations and immune checkpoint expressions, and different sensitivities to drugs.Conclusion: The research findings demonstrate that crlncRNAs can be used to predict the prognosis and immune microenvironment of patients suffering from BCa, and differentiate between BCa subgroups to improve the individual therapy of BCa.

BackgroundAlthough many studies reported the effectiveness of transarterial chemoembolization (TACE) combined with radiofrequency ablation (RFA) or surgical resection (SR) in the treatment of hepatocellular carcinoma (HCC), the efficacy of these two strategies remains controversial. Therefore, this meta-analysis aimed to evaluate and compare the efficacy of sequential use of TACE plus RFA (TACE + RFA) and SR alone in treating HCC.MethodsRelevant studies with unmatched and propensity score-matched patients were identified by comprehensive search of MEDLINE, PubMed, EMBASE, Web of Science, and Cochrane electronic databases. Meta-analysis was conducted using Review Manager (RevMan) software version 5.4.1. Finally, 12 eligible studies were included in this study, including 11 case–control studies and 1 randomized controlled trial. The primary outcome of interest for this study was to compare the 1-, 3-, and 5-year overall survival (OS) and disease-free survival (DFS), major complications, 5-year OS in different tumor diameters between the two treatment strategies, and hospital stay time.ResultsHCC patients who received TACE + RFA had a lower incidence of complication rates and shorter hospital stay time than those who received SR alone. Among these studies using propensity score-matched cohorts, SR had better 3- and 5-year OS than TACE + RFA, whereas there were no significant differences between TACE + RFA and SR regarding the 1-, 3-, and 5-year DFS. When the tumor diameter is longer than 3 cm, the 5-year OS rate is better when SR is selected.ConclusionThere was no significant difference in the short-term survival outcomes between TACE + RFA and SR in HCC patients. Moreover, SR is superior to TACE + RFA in terms of long-term beneficial effects but may result in a higher risk of major complications and a longer hospital stay time.

Abstract Background Quantifying CO2 emissions from cities is of great importance because cities contribute more than 70% of the global total CO2 emissions. As the largest urbanized megalopolis region in northern China, the Beijing-Tianjin-Hebei (Jing-Jin-Ji, JJJ) region (population: 112.7 million) is under considerable pressure to reduce carbon emissions. Despite the several emission inventories covering the JJJ region, a comprehensive evaluation of the CO2 emissions at the prefectural city scale in JJJ is still limited, and this information is crucial to implementing mitigation strategies. Results Here, we collected and analyzed 8 published emission inventories to assess the emissions and uncertainty at the JJJ city level. The results showed that a large discrepancy existed in the JJJ emissions among downscaled country-level emission inventories, with total emissions ranging from 657 to 1132 Mt CO2 (or 849 ± 214 for mean ± standard deviation (SD)) in 2012, while emission estimates based on provincial-level data estimated emissions to be 1038 and 1056 Mt. Compared to the mean emissions of city-data-based inventories (989 Mt), provincial-data-based inventories were 6% higher, and national-data-based inventories were 14% lower. Emissions from national-data-based inventories were 53–75% lower in the high-emitting industrial cities of Tangshan and Handan, while they were 47–160% higher in Beijing and Tianjin than those from city-data-based inventories. Spatially, the emissions pattern was consistent with the distribution of urban areas, and urban emissions in Beijing contributed 50–70% of the total emissions. Higher emissions from Beijing and Tianjin resulted in lower estimates of prefectural cities in Hebei for some national inventories. Conclusions National-level data-based emission inventories produce large differences in JJJ prefectural city-level emission estimates. The city-level statistics data-based inventories produced more consistent estimates. The consistent spatial distribution patterns recognized by these inventories (such as high emissions in southern Beijing, central Tianjin and Tangshan) potentially indicate areas with robust emission estimates. This result could be useful in the efficient deployment of monitoring instruments, and if proven by such measurements, it will increase our confidence in inventories and provide support for policy makers trying to reduce emissions in key regions.

The web crossed truss boom is one of the commonly used truss boom structures of crawler cranes. However, the existing calculations fail to consider the limiting effect of the web members' bending resistance on the chord members, and cannot give full play to the load-bearing capacity of the existing structure. This paper takes the top section of the Crawler crane truss boom as the research object. The single-span truss theoretical model is established according to Timoshenko's elastic stability theory. And the theoretical critical load of the variable cross-section boom is obtained with full consideration of the limitation of the web member's bending resistance on the chord members. The finite element method simulation model is compared and verified. Compared with a large number of simulation experiments and theoretical calculations, it can be concluded that the theoretical calculations in this article are highly consistent with the simulation results, verified the assumptions that the web members' bending resistance help to improve the bending resistance of the chord members, and this will provide certain reference to the engineering designers.

The deviation of conveyor belts is a key factor that restricts material conveying efficiency of horizontal curves. An evaluation system of the deviation state of curve conveyor belt based on the ARIMA–LSTM combined prediction model is proposed in this study to investigate the deviation state of the conveyor belt. This system has been used for detection, prediction, deviation correction, and early warning of the conveyor belt deviation state. First, the experiment system of the conveyor belt deviation was built. The conveyor belt deviation images were collected using the machine vision method, and the conveyor belt deviation state data set was established. Second, the mechanical model of curve conveyor belt deviation is presented and solved. The correctable deviation range of the idler frame under different elevations and trough angles was obtained by solving the problem. Third, the ARIMA–LSTM combined prediction model of conveyor belt deviation based on series-parallel weighing method was put forward. The analysis results showed that the ARIMA–LSTM combined prediction model is suitable for the prediction of conveyor belt deviation in terms of accuracy, fitting degree, time, and performance. Finally, the deviation state evaluation system was established to realize the visual fusion of the ARIMA–LSTM combined model in the range of correctable deviation of the idler frame. The OCSVM algorithm was used to detect the abnormal deviation of the conveyor belt. The experiment shows that the evaluation system can predict and send out early warning signals according to the detection results, provide corresponding suggestions for adjusting the deviation correction angle, and realize an efficient and intelligent solution for the evaluation of the curved section belt deviation state.

Parkinson’s disease (PD) is a common age-associated neurodegenerative motor disorder, which is mainly caused by dopaminergic neuron loss in the substantia nigra. This study aimed to evaluate the function and the underlying molecular mechanism of itaconate in PD. PD models were established in vivo and in vitro using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 1-methyl-4-phenylpyridinium (MPP+), respectively. Pole and rotarod tests were applied to evaluate the motor coordination of mice. The expression of tyrosine hydroxylase (TH) in MPTP-induced mice and the MPP+ revulsive PD cell model were detected using Western blotting and immunofluorescence. The inflammatory factors level was detected by quantitative real-time polymerase chain reaction. The content of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS) in substantia nigra, striatum, and SH-SY5Y cells were analyzed. Moreover, the apoptosis of MPP+ revulsive SH-SY5Y cells was determined using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) staining and flow cytometry. The expression of apoptosis- and Nod-like receptor family protein 3 (NLRP3) inflammasome-associated proteins was measured using Western blotting and immunofluorescence. Itaconate attenuated motor deficits of MPTP-induced PD mice. Itaconate inhibited dopamine neuronal damage, inflammatory response, oxidative stress, and neuronal apoptosis in MPTP-caused PD mice and the MPP+ revulsive PD cell model. Additionally, itaconate notably repressed the activation of NLRP3 inflammasome. This research demonstrated that itaconate could attenuate neuroinflammation and exert dopamine neuroprotection in PD through inhibiting NLRP3 inflammasome.

This paper presents a control method for the problem of trajectory jitter and poor tracking performance of the end of a three-joint rigid manipulator. The control is based on a high-order particle swarm optimization algorithm with an improved sliding mode control neural network. Although the sliding mode variable structure control has a certain degree of robustness, because of its own switching characteristics, chattering can occur in the later stage of the trajectory tracking of the manipulator end. Hence, on the basis of the high-order sliding mode control, the homogeneous continuous control law and super-twisting adaptive algorithm were added to further improve the robustness of the system. The radial basis function neural network was used to compensate the errors in the modeling process, and an adaptive law was designed to update the weights of the middle layer of the neural network. Furthermore, an improved particle swarm optimization algorithm was established and applied to optimize the parameters of the neural network, which improved the trajectory tracking of the manipulator end. Finally, MATLAB simulation results indicated the validity and superiority of the proposed control method compared with other sliding mode control algorithms.

Residential solid fuel use constitutes a large amount of air pollution but has been gradually replaced by other cleaner energy during the past three decades. Here the authors investigated the contribution of rural residential sector to ambient PM2.5 pollution and the resulting climate forcing and health impacts, and find that the remaining large quantities of solid fuels used in rural households are still a major contributor to ambient air pollution despite of decrease in its pollutant emissions and relative contribution to PM2.5 due to the clean energy transition.

Because of the severe air pollution in northern China, facemasks have gained popularity in this area in recent years. Although the results of previous studies have shown the effectiveness of wearing facemasks for intercepting particles, the individual differences and the overall health benefits of wearing facemasks have not been comprehensively documented. In this study, using both model and personal tests under various conditions, we test eight major brands of facemasks for their removal efficiencies (REs) of particulate matter (PM) in six size ranges (from 0.3 μm to >10 μm). The results are used to assess the overall exposure reduction at the individual and population levels in Beijing. We find significant differences in REs among PM sizes, facemask brands, pollution levels, and genders. Combining the information on the usage of various brands, facemask wearing rates, and PM2.5 concentrations in the ambient and indoor air in this area, we evaluate the overall effect of facemask wearing on PM2.5 exposure reduction. It is quantitatively demonstrated that because people spend most time indoors, facemask protection is limited. For facemask wearers, the overall exposure can be reduced by less than 20%, whereas the reduction rate is as low as 2.4 ± 1.6% for the entire adult populations even in the year with the highest level of pollution with an annual mean PM2.5 concentration of 102 ± 98 μg∙m−3. As a strategy of self-protection from long-term exposure to particulate matter, wearing facemasks outdoors is inferior to the installation of indoor air purifiers.

The friction and wear tests of 2205 dual-phase steel with different solution temperatures were carried out, and the effects of solution temperature on the microstructure and friction and wear properties of the steel were determined. Results show that, as the solution temperature increases, the morphology of the austenite phase in 2205 duplex stainless steel gradually changes from fibrous strips to short rods and islands with a more uniform distribution. Additionally, the ferrite content increases with a rise in solution temperature, reaching 56.3% after solution treatment at 1160°C. It was also found that, between 1000°C and 1160°C, the friction coefficient curves of 2205 dual-phase steel and silicon nitride balls have similar characteristics. Under 100 N dry friction, with the increase of solution temperature and oxygen distribution area, the wear mechanism of 2205 dual-phase steel gradually expanded from local oxidation wear to adhesive wear and exfoliation wear.

Thanks to the geometric and material complexity of additive manufacturing, the design space of mechanical parts has been developed, in which lattice filling structure customization can be applied to the solid filling of mechanical parts to achieve the goal of mechanical structure lightweight. A kind of diamond lattice structure unit is designed by imitating the natural method based on Design for Additive Manufacturing of mechanical parts. The mathematical model of the relative density and mechanical properties of the unit are established, and the relationship between the two is obtained, which is verified by simulations; then the relatively uniform results are obtained. The variable density hypothesis of diamond lattice structure is proposed, the methods of simulations and compression tests are used to verify the hypothesis, and the results show that the variable density structure with the density of the filling element decreasing gradually with the stress point as the center has better compression performance and concurrently verify the correctness and applicability of the equivalent modulus of elasticity mathematical model. The results of this study can be applied to the solid sandwich filling of pressure mechanical parts, and the stress density matching relationship can be carried out to further specific design.

PM2.5 (particulate matter with an aerodynamic size ≤ 2.5 μm) of indoor origins is a dominant contributor to the overall air pollution exposure. Although some sophisticated models have been developed to simulate indoor air quality for individual households, it is still challenging to quantify indoor PM2.5 on a regional scale, which is critical for health impact assessments. In this study, a new model was developed to predict indoor PM2.5 concentrations by quantifying the external penetration, as well as the internal contributions. The model was parameterized based on a set of simultaneously measured indoor and outdoor PM2.5 concentrations at five-second temporal resolution for 53 households in Beijing. This study found that indoor PM2.5 concentrations were significantly correlated with those in the outdoor environment with an approximately 1-h lag-time on average. Outdoor-to-indoor penetration dominated the contribution to indoor PM2.5 during polluted hours with relatively high ambient PM2.5 concentrations, while the indoor PM2.5, during clean hours, was contributed by internal sources, including smoking, cooking, incense burning, and human disturbance. The influence of windows, house area, and air purifier use was addressed in the new model. The model was applied to evaluate indoor PM2.5 concentrations in six urban districts of Beijing via an uncertainty analysis. The model was developed based on and applied to households using clean residential energy, and it would be interesting also important to evaluate it in households using solid fuels.

To obtain the failure evolution law, a pullout test model of the anchor system is proposed based on the digital image correlation (DIC) measurements. By the study of the displacement field, the strain field, and the force transfer law of the anchor system under the pulling load, the failure law of the anchor system is revealed. The results show that (1) the failure mode and the ultimate bearing capacity of the anchor system are related to the thickness of the anchor agent; (2) in the anchor system, the pulling force is gradually transferred from the loading end to the free end along the steel bar, and the greater the thickness of the anchoring agent, the deeper the transfer range; (3) during the loading, the deformation of the anchoring system is mainly concentrated at the interface between the anchoring agent and the concrete and expands to the depth along the steel bar; and (4) the failure evolution rate of the anchorage system is related to the loading stage. The failure evolution of the anchor system can be divided into the elastic phase, the plastic phase, and the deformation rebound phase.

Shallow-water depth information is essential for ship navigation and fishery farming. However, the accurate acquisition of shallow-water depth has been a challenge for marine mapping. Combining Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2) bathymetry data with multispectral data, satellite-derived bathymetry is a promising solution through which to obtain bathymetric information quickly and accurately. This study proposes a photon refraction correction method considering sea-surface undulations to address errors in the underwater photons obtained by the ICESat-2. First, the instantaneous sea surface and beam emission angle are integrated to determine the sea-surface incidence angle. Next, the distance of photon propagation in water is determined using sea-surface undulation and Snell’s law. Finally, position correction is performed through geometric relationships. The corrected photons were combined with the multispectral data for bathymetric inversion, and a bathymetric map of the Yongle Atoll area was obtained. A bathymetric chart was created using the corrected photons and the multispectral data in the Yongle Atoll. Comparing the results of different refraction correction methods with the data measured shows that the refraction correction method proposed in this paper can effectively correct bathymetry errors: the root mean square error is 1.48 m and the R2 is 0.86.

Idlers, one of the important parts of belt conveyors, are substantial and constitute approximately one-third of the equipment cost. Therefore, idlers in conveyor systems must be optimized. This study designs a new kind of idler on the basis of theoretical calculation and coupling simulation, with the shaft, shell, and labyrinth gland of the idler as optimization variables and overall cost and life span of the idler as objective functions. According to each independent variable of the idler, this idler adopts the equal strength beam concept and maximizes the overall carrying capacity of the shaft and the bearing by using a hollow step-shaft. The idler effectively adopts the one-piece casting labyrinth gland, thereby automatically enhancing the sealing effect with a screw structure in different rotation directions. The simulation analysis shows that under certain working conditions, the stress of the new idler shaft is one-third of the stress of the traditional idler shaft, and the strain is one-half of the traditional idler shaft, and the effect is obvious. A reliability analysis of the idler system is described in this work through the establishment of a fault tree, determination of the logical relationship of each component and provides methods for further research. Finally, the idler is verified to be practical in engineering applications, with a 10% cost reduction and considerable economic benefits.

A mine bolter is a fast, safe and economical support equipment, in which the manipulator is the key component for its parallel operation. In this study, the kinematics of mine bolter manipulator is selected as the research object. Aiming at the problem of the dynamic system response estimation of positive solution matrix with uncertain parameters, an interval estimation analysis method based on Chebyshev polynomial is proposed. The response envelope interval of the forward kinematics solution matrix of the manipulator with uncertain parameters is investigated using three types of surrogate models: scanning method, tensor product and collocation method. The feasibility and efficiency of the proposed algorithm are proved by a prototype test. The study of response interval with uncertain parameters has become a new method for predicting the spatial trajectory tracking and location of the manipulator to ensure that its prediction error is minimal.

The indentation rolling resistance of a belt conveyor with stable operation accounts for more than 60% of the total resistance. Thus, the effective reduction of indentation rolling resistance and its energy consumption have attracted considerable attention of engineers. Indentation rolling resistance is due to the viscoelasticity of conveyor belt. A three-parameter Kelvin solid model is used to characterize the viscoelasticity of materials. The parameters of the Kelvin solid model include two elastic moduli E 0 and E 1 and one viscous coefficient η 1 , and their fitting functions are obtained by completing a dynamic tensile test. A mathematical model of indentation rolling resistance is derived, on the basis of theoretical analysis, which is directly expressed by belt speed, idler radius, and cover layer thickness under the conveyor belt, and is indirectly expressed by normal load and temperature. The influence of five factors on indentation rolling resistance and the influence of combined conditions of any two factors on indentation rolling resistance are separately analyzed on the basis of the mathematical model. The theory in this study is accurate based on the consistency between the theoretical calculation and experimental results. In practical engineering, the operating conditions of belt conveyors are any combination of all factors. Various factors should be considered to reduce indentation rolling resistance.

Numerical study was performed to determine the fatigue limit of metallic glass under tension-compression cyclic loading. A revised free-volume theory which considers the hydrostatic stress was utilized to make the predictions. Systematical simulations showed that a higher strain amplitude is prone to making the sample completely damaged earlier. However, lower strain fluctuations could result in a longer fatigue life. Shear banding evolution history described by free-volume localization could reasonably explain the mechanical responses of different samples. In addition, compressive loading could give rise to a higher stress than that under tensile loading because of hydrostatic stress contribution. In the end, a correlation between fatigue life and applied strain amplitude was plotted which could supply a guidance for designing the engineering application of metallic glass under periodic loading.

The calculation of the critical force of the stepped column model of telescopic boom crane is the key to stability calculation of all-terrain crane. In slightly bending theory, differential equation can be built up, and then the deflection curve of ideal column can be obtained. Using this curve and the Rayleigh–Ritz method, the Euler force of the ideal column can be obtained. For n -stepped columns, Euler forces and the effective length coefficients can be acquired using the deflection curve of the ideal column and parabolic curve, respectively, combined with the Rayleigh–Ritz method. Differential equations of the n -stepped telescopic boom are established based on the vertical and horizontal buckling theory. The recursive formula of the stability of the n -stepped telescopic boom is deduced by the mathematical induction method. For the transcendental equation in the recursive formula, combined with the structural force characteristics and supplementary formulas, the Levenberg–Marquardt numerical optimization algorithm is used to solve the equations with n unknowns. Length coefficients obtained by the three methods are compared using GB3811-2008 and ANSYS 17.0. The results show that the accuracy of the numerical algorithm is the highest, and the first two algorithms will produce large errors when the stepped columns have more steps.

At present, it is the conventional inner rotor motor instead of the internal combustion engine that is adopted by most electric cars. However, compared to the traditional centralized driving pattern, cars adopting a distributed direct driving pattern have higher drive efficiency and more stable handling. Given this background, a kind of direct-drive outer rotor motor with 40 poles and 42 slots applied for middle or low speed electric cars was designed. The core of this study included the electromagnetic analysis and structural design of the motor. Firstly, the material and dimension parameters of the stator and rotor were selected and calculated by the traditional method. The air-gap length and pole-arc coefficient were optimized using an RMxprt module, which was developed using the equivalent magnetic circuit method. Then, a two-dimensional finite-element model was established using ANSYS Maxwell. The magnetic field and torque characteristics of the model were then analyzed. Results show that the design of the motor is reasonable. In addition, a method for reducing the torque ripple was proposed and verified by simulation.

Intrinsic short hole diffusion length is a well-known problem for α-Fe2O3 as a visible-light photocatalytic material. In this paper, a nanodisk morphology was designed to remarkably enhance separation of electron-hole pairs of α-Fe2O3. As expected, α-Fe2O3 nanodisks presented superior photocatalytic activity toward methylene blue degradation: more than 90% of the dye could be photodegraded within 30 min in comparison with a degradation efficiency of 50% for conventional Fe2O3 powder. The unique multilayer structure is thought to play a key role in the remarkably improved photocatalytic performance. Further experiments involving mechanism investigations revealed that instead of high surface area, ·OH plays a crucial role in methylene blue degradation and that O·2− may also contribute effectively to the degradation process. This paper demonstrates a facile and energy-saving route to fabricating homogenous α-Fe2O3 nanodisks with superior photocatalytic activity that is suitable for the treatment of contaminated water and that meets the requirement of mass production.

Properly evaluating the overall performance of tubular scraper conveyors (TSCs) can increase their overall efficiency and reduce economic investments, but such methods have rarely been studied. This study evaluated the overall performance of TSCs based on the technique for order of preference by similarity to ideal solution (TOPSIS). Three conveyors of the same type produced in the same factory were investigated. Their scraper space, material filling coefficient, and vibration coefficient of the traction components were evaluated. A mathematical model of the multiattribute decision matrix was constructed; a weighted judgment matrix was obtained using the DELPHI method. The linguistic positive-ideal solution (LPIS), the linguistic negative-ideal solution (LNIS), and the distance from each solution to the LPIS and the LNIS, that is, the approximation degrees, were calculated. The optimal solution was determined by ordering the approximation degrees for each solution. The TOPSIS-based results were compared with the measurement results provided by the manufacturer. The ordering result based on the three evaluated parameters was highly consistent with the result provided by the manufacturer. The TOPSIS-based method serves as a suitable evaluation tool for the overall performance of TSCs. It facilitates the optimal deployment of TSCs for industrial purposes.