Prognostic evaluation of the novel blueprint of DNA methylation sites by integrating bulk RNA-sequencing and methylation modification data in endometrial cancer.

INTRODUCTION: Endometrial cancer (EC) is a prevalent malignancy affecting the female population, with an increasing incidence among younger age groups. DNA methylation, a common epigenetic modification, is well-established to play a key role in cancer progression. We suspected whether DNA methylation could be used as biomarkers for EC prognosis. METHODS: In the present study, we analyzed bulk RNA-sequencing data from 544 EC patients and DNA methylation data from 430 EC patients in the TCGA-UCEC cohort. We applied weighted correlation network analysis to select a key gene set associated with panoptosis. We conducted correlation analysis between transcriptomic data of the selected key genes and DNA methylation data to identify valuable DNA methylation sites. These sites were further screened by Cox regression and least absolute shrinkage and selection operator analysis. Immune microenvironment differences between high-risk and low-risk groups were assessed using single-sample gene set enrichment analysi, xCell and MCPcounter algorithms. RESULTS: Our results identified five DNA methylation sites (cg03906681, cg04549977, cg06029846, cg10043253 and cg15658376) with significant prognostic value in EC. We constructed a prognostic model using these sites, demonstrating satisfactory predictive performance. The low-risk group showed higher immune cell infiltration. Notably, methylation of site cg03906681 was negatively related to CD8 T cell infiltration, whereas cg04549977 exhibited positive correlations with immune infiltration, particularly in macrophages, activated B cells, dendritic cells and myeloid-derived suppressor cells. PD0325901_1060 was strongly correlated with risk scores, indicating a potential therapeutic response for high-risk EC patients. CONCLUSION: We have developed a robust DNA methylation-based prognostic model for EC, which holds promise for improving prognosis prediction and personalized treatment approaches. These findings may contribute to better management of EC patients, particularly in identifying those at higher risk who may benefit from tailored interventions.

Comparison of NAFLD, MAFLD and MASLD characteristics and mortality outcomes in United States adults.

BACKGROUND & AIMS: Following the classification of metabolic dysfunction-associated fatty liver disease (MAFLD), non-alcoholic fatty liver disease (NAFLD) has recently been redefined again as metabolic dysfunction-associated steatotic liver disease (MASLD). However, the distinctions in characteristics and mortality outcomes between NAFLD, MAFLD and MASLD remain unclear. METHODS: We analysed data from 7519 participants in the third National Health and Nutrition Examination Surveys of United States (US) and their linked mortality until 2019. Survey weight-adjusted multivariable Cox proportional model was used to study the mortality over three terms. RESULTS: The prevalence of NAFLD, MAFLD and MASLD was 18.5%, 19.3% and 20.8%, respectively. Most individuals with NAFLD (94.5%) or MAFLD (100%) can be classified as MASLD, while a relatively low percentage of those with MASLD were also diagnosed with either NAFLD (84.1%) or MAFLD (92.7%). During a median follow-up of 26.9 years, both MAFLD and MASLD were associated with increased risk of all-cause mortality (adjusted hazard ratio [aHR] 1.18, 95% CI 1.04-1.33 and 1.19, 1.06-1.34, respectively), this association was mainly observed in NAFLD-/MASLD+ subgroups. NAFLD was not associated with all-cause mortality. However, all three terms were associated with an increased risk of all-cause mortality in individuals with advanced fibrosis (aHR: 1.71-1.81). Subgroup analyses showed that higher risk of all-cause mortality for both MAFLD and MASLD were observed among older adults (≥65 year), non-Hispanic whites and those without diabetes. CONCLUSIONS: Both MASLD and MALFD were linked to higher all-cause mortality risk, but MASLD identified a greater number of individuals compared to MAFLD.

Humoral responses after primary and booster SARS-CoV-2 inactivated vaccination in patients with chronic hepatitis B virus infection: A longitudinal observational study.

Given the pandemic of severe acute respiratory syndrome coronavirus 2 Omicron variants, booster vaccination (BV) using inactivated virus vaccines (the third dose) has been implemented in China. However, the immune responses after BV, especially those against Omicron, in patients with chronic hepatitis B virus (HBV) infection (CHB) are unclear. In this prospective longitudinal study, 114 patients with CHB and 68 healthy controls (HCs) were recruited after receiving inactivated vaccination. The anti-receptor-binding domain (RBD) immunoglobulin G (IgG), neutralizing antibodies (NAbs), neutralization against Omicron (BA2.12.1, BA.4/5), and specific B/T cells were evaluated. In patients, anti-RBD IgG was elevated significantly after BV; the titers were as high as those in HCs. Similar results were obtained for the NAbs. However, compared with that against wild type (WT), the neutralization against Omicron was compromised after BV. The frequency of RBD+ atypical memory B cells increased, but spike-specific cluster of differentiation 4+ /8+ T cells remained unchanged after BV. Moreover, no serious adverse events or HBV reactivation were observed after BV. These results suggest that BV significantly enhanced antibody responses against WT; however, it resulted in compromised antibody responses against Omicron in patients with CHB. Hence, new all-in-one vaccines and optimal vaccination strategies should be studied promptly.

Design, synthesis, and evaluation of JTE-013 derivatives as novel potent S1PR2 antagonists for recovering the sensitivity of colorectal cancer to 5-fluorouracil.

Targeting sphingosine-1-phosphate receptor 2 (S1PR2) has been proved as a promising strategy to reverse 5-fluorouracil (5-FU) resistance. Here, we report the discovery of the novel JTE-013 derivative compound 37 h as a more effective S1PR2 antagonist to reverse 5-FU resistance in SW620/5-FU and HCT116DPD cells than JTE-013 and previously reported compound 5. Compound 37 h could effectively bind S1PR2 and reduce its expression, thus leading to decreased expression of JMJD3 and dihydropyrimidine dehydrogenase (DPD), while also increasing the level of H3K27me3 to decrease the degradation of 5-FU and thereby increase its intracellular concentration in SW620/5-FU, HCT116DPD, and L02 cells. Furthermore, compound 37 h showed good selectivity to other S1PRs and normal colon cell line NCM460. Western blot analysis demonstrated that compound 37 h could abrogate the FBAL-stimulated upregulation of DPD expression by S1PR2. Importantly, compound 37 h also showed favorable metabolic stability with a long half-life (t1/2) of 7.9 h. Moreover, compound 37 h significantly enhanced the antitumor efficacy of 5-FU in the SW620/5-FU animal model. Thus, the JTE-013-based derivative compound 37 h represents a promising lead compound for the development of novel 5-FU sensitizers for colorectal cancer (CRC) therapy.

Identification of new reference genes for colony counting by reverse-transcription quantitative PCR in Bifidobacterium animalis.

Bifidobacterium animalis, one of the predominant bacteria in the intestines of humans and other mammals, is widely added to dairy products. We employed RNA sequencing to analyze gene expression variance on a genome-wide scale and found stable reference genes (RG) in B. animalis. A total of 1,665 genes were identified by analyzing the data from the transcriptome under 4 different conditions, and 13 probable candidate RG with variation coefficient values <0.1 were validated using reverse-transcription quantitative PCR (RT-qPCR). The amplification efficiency of candidate RG were ranging from 94.16% to 126.25%. We integrated the analysis results of BestKeeper, geNorm, NormFinder, and RefFinder algorithms and revealed that rplD and atpA comprehensive ranked 1.68 and 2.82, respectively, which were more stable than traditional RG. Compared with plate count (1.58 × 106 cfu/mL), the concentrations of B. animalis AR668 by RT-qPCR using rplD, atpA, and 16S rRNA as RG were 2.27 × 106, 2.24 × 106, and 6.66 × 106 cfu/mL, respectively, after 10 h of fermentation in fermented skim milk. It suggested that rplD and atpA as RG can be accurate for colony counting of B. animalis. Our study provides the foundation for more accurate analysis of colony counting by RT-qPCR of B. animalis in dairy foods.

Fault Root Cause Tracking of the Mechanical Components of CNC Lathes Based on Information Transmission.

This study proposes a new method for the immediate fault warning and fault root tracing of CNC lathes. Here, the information acquisition scheme was formulated based on the analysis of the coupling relationship between the mechanical parts of CNC lathes. Once the collected status signals were de-noised and coarse-grained, transfer entropy theory was introduced to calculate the net entropy of information transfer between the mechanical parts, after which the information transfer model was constructed. The sliding window method was used to determine the probability threshold interval of the net information transfer entropy between the lathe mechanical parts under different processing modes. Therefore, the transition critical point was determined according to the information entropy, and the fault development process was clarified. By analyzing the information transfer changes between the parts, fault early warning and fault root tracking on the CNC lathe were realized. The proposed method realizes the digitalization and intelligentization of fault diagnosis and has the advantages of timely and efficient diagnosis. Finally, the effectiveness of the proposed method is verified by a numerical control lathe tool processing experiment.

Safety and antibody response to inactivated COVID-19 vaccine in patients with chronic hepatitis B virus infection.

BACKGROUND AND AIMS: The safety and antibody responses of coronavirus disease 2019 (COVID-19) vaccination in patients with chronic hepatitis B (CHB) virus infection is still unclear, and exploration in safety and antibody responses of COVID-19 vaccination in CHB patients is significant in clinical practice. METHODS: 362 adult CHB patients and 87 healthy controls at an interval of at least 21 days after a full-course vaccination (21-105 days) were enrolled. Adverse events (AEs) were collected by questionnaire. The antibody profiles at 1, 2 and 3 months were elucidated by determination of anti-spike IgG, anti-receptor-binding domain (RBD) IgG, and RBD-angiotensin-converting enzyme 2 blocking antibody. SARS-CoV-2 specific B cells were also analysed. RESULTS: All AEs were mild and self-limiting, and the incidence was similar between CHB patients and controls. Seropositivity rates of three antibodies were similar between CHB patients and healthy controls at 1, 2 and 3 months, but CHB patients had lower titers of three antibodies at 1 month. Compared to healthy controls, HBeAg-positive CHB patients had higher titers of three antibodies at 3 months (all P < .05) and a slower decline in antibody titers. Frequency of RBD-specific B cells was positively correlated with titers of anti-RBD IgG (OR = 1.067, P = .004), while liver cirrhosis, antiviral treatment, levels of HBV DNA, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and total bilirubin (TB) were not correlated with titers of anti-RBD IgG. CONCLUSIONS: Inactivated COVID-19 vaccines were well tolerated, and induced effective antibody response against SARS-CoV-2 in CHB patients.

ICP-MS and Photothermal Dual-Readout Assay for Ultrasensitive and Point-of-Care Detection of Pancreatic Cancer Exosomes.

Pancreatic cancer is known to have a high mortality rate, and its early diagnosis remains challenging due to the occult location of the pancreas. Exosomes derived from pancreatic cancer cells specifically express glypican-1, which may provide a liquid biopsy opportunity for the early diagnosis of pancreatic cancer. Herein, an inductively coupled plasma mass spectrometry (ICP-MS) and photothermal dual-readout platform was proposed for the ultrasensitive and point-of-care analysis of pancreatic cancer exosomes. In our design, exosomes were specifically captured by the sandwich immunoassay, and simultaneously, alkaline phosphatase was introduced in a low-background manner. The alkaline phosphatase triggered the hydrolysis of l-ascorbic acid 2-phosphate to produce ascorbic acid, followed by the etching of Fe3O4@MnO2 nanoflowers. As a result, the Mn2+ generated by etching stripped off the Fe3O4 and was quantified using ICP-MS. Meanwhile, the reduced Fe3O4@MnO2 was applied for the photothermal assay by oxidizing dopamine with MnO2. The protocol exhibits a detection limit down to 19.1 particles mL-1, which is the most sensitive protocol reported so far. To our knowledge, this is the first endeavor for exosome quantification using ICP-MS and photothermal methods. The developed dual-readout platform not only is capable of distinguishing pancreatic cancer patients from healthy people, but also shows excellent discernibility of individual differences at low concentrations of exosomes. This dual-readout assay is a promising platform for the ultrasensitive and point-of-care detection of exosomes in liquid biopsy-based early cancer diagnosis.

High concentrations of hypochlorous acid-based disinfectant in the environment reduced the load of SARS-CoV-2 in nucleic acid amplification testing.

During the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic, chlorine-containing disinfectants have been widely used in nucleic acid amplification testing laboratories. Whether the use of disinfectants affect the results of viral nucleic acid amplification is unknown. We examined the impact of different hypochlorous acid (HOCl) concentrations on the quantitative results of SARS-CoV-2 by real-time reverse-transcription polymerase chain reaction (RT-PCR). We also explored the mechanisms and models of action of chlorine-containing disinfectants that affected the detection of SARS-CoV-2. The results showed that different HOCl concentrations and different action times had an impact on the SARS-CoV-2 results. High concentrations of ambient HOCl have a greater impact than low concentrations, and this effect will increase with the extension of the action time and with the increase in ambient humidity. Compared with the enzymes or the extracted RNA required for RT-PCR, the impact of HOCl on the SARS-CoV-2 detection is more likely to be caused by damage to primers and probes in the PCR system. The false negative result still existed after changing the ambient disinfectant to ethanol but not peracetic acid. The use of HOCl in the environment will have an unpredictable impact on the nucleic acid test results of SARS-CoV-2. In order to reduce the possibility of false negative of SARS-CoV-2 nucleic acid test and prevent the spread of epidemic disease, environmental disinfectants should be used at the beginning and end of the experiment rather than during the experimental operation.

Plasmonic Colorimetric Biosensor for Sensitive Exosome Detection via Enzyme-Induced Etching of Gold Nanobipyramid@MnO2 Nanosheet Nanostructures.

Exosomes involved in tumor-specific processes display excellent potential in the early diagnosis of cancer. Herein, a highly sensitive plasmonic colorimetric biosensor was proposed for exosome quantification. The sensing strategy mainly includes two steps: exosome-triggered competitive reaction and etching of gold nanobipyramid@MnO2 nanosheet nanostructures (Au NBP@MnO2 NSs). A competitive reaction between exosomes and placeholder chains induced by exosomes can translate the signal of exosomes into the amount of alkaline phosphatase, which simplifies the experimental process and amplifies the signal. The etching of Au NBP@MnO2 NSs by ascorbic acid generated from the hydrolysis of l-ascorbic acid 2-phosphate by alkaline phosphatase changes the refractive index of Au NBPs, accompanied by the blue shift of the longitudinal localized surface plasmon resonance peak. Profiting from the signal amplification of the competitive reaction and superior refractive index sensitivity of colorimetric substrates, this protocol exhibits high sensitivity toward exosomes within 8.5 × 102 to 8.5 × 104 particles µL-1, along with a detection limit of 1.35 × 102 particles µL-1, which is more sensitive than previously reported colorimetric methods. In addition, a sensitive multicolor visual detection of exosomes was realized by adjusting the aspect ratio of Au NBPs. It is worth mentioning that the Au NBP@MnO2 NSs was synthesized through in situ growth of MnO2 nanosheets on Au NBPs, and the attractive optical properties and ease of etching make Au NBP@MnO2 NSs promising candidates for plasmonic detection.

Multiplexed detection of micro-RNAs based on microfluidic multi-color fluorescence droplets.

In this work, simple, rapid, and low-cost multiplexed detection of tumor-related micro-RNAs (miRNAs) was achieved based on multi-color fluorescence on a microfluidic droplet chip, which simplified the complexity of light path to a half. A four-T-junction structure was fabricated to form uniform nano-volume droplet arrays with customized contents. Multi-color quantum dots (QDs) used as the fluorescence labels were encapsulated into droplets to develop the multi-path fluorescence detection module. We designed an integrated multiplex fluorescence resonance energy transfer system assisted by multiple QDs (four colors) and one quencher to detect four tumor-related miRNAs (miRNA-20a, miRNA-21, miRNA-155, and miRNA-221). The qualitative analysis of miRNAs was realized by the color identification of QDs, while the quantitative detection of miRNAs was achieved based on the linear relationship between the quenching efficiency of QDs and the concentration of miRNAs. The practicability of the multiplex detection device was further confirmed by detecting four tumor-related miRNAs in real human serum samples. The detection limits of four miRNAs ranged from 35 to 39 pmol/L was achieved without any target amplification. And the linear range was from 0.1 nmol/L to 1 µmol/L using 10 nL detection volume (one droplet) under the detection speed of 320 droplets per minute. The multiple detection system for miRNAs is simple, fast, and low-cost and will be a powerful platform for clinical diagnostic analysis. Graphical abstract.

Colloidal photonic crystal array chip based on nanoparticle self-assembly on patterned hydrophobic surface for signal-enhanced fluorescent assay of adenosine.

A controllable approach for preparing a portable colloidal photonic crystal (CPC) array chip is presented. The approach was inspired by the confinement effect of nanoparticle self-assembly on patterned surface. Hydrophobic polydimethylsiloxane substrate with reproducible micro-region array was fabricated by soft-lithography. The substrate was employed as the patterned template for self-assembly of monodisperse polystyrene nanoparticles. The CPC units can be prepared in several minutes, and exhibit consistent reflection wavelength. By adjusting the size of polystyrene nanoparticles and the shape of micro-regions, CPC units with multiple structure, colors and geometries were obtained. The CPC array chip features fluorescence enhancement owing to the optical modulation capability of the periodic nanostructure of the self-assembled CPC. With the reflection wavelength (523 nm) of green CPC units overlapping the emission wavelength (520 nm, with excitation wavelength of 490 nm) of 6-carboxyfluorescein-labeled DNA probe, the fluorescence intensity increased more than 10-fold. For signal-amplified assay of adenosine, the concentration range of linear response was 5.0 × 10-5 mol L-1 to 1.0 × 10-3 mol L-1, and the limit of detection was 1.3 × 10-6 mol L-1. Because of the enhancement effect of photonic crystal, the fluorescence images were more readable from the CPC array chip, compared with those from the planar substrate. The chip has potential applications in multiplex determination with high-throughput via encoding strategy based on the tunable structure, color or geometric shape. Graphical abstractSchematic diagram of signal-enhanced fluorescent detection of adenosine based on the colloidal photonic crystal array chip (PDMS, polydimethylsiloxane; PS NPs, polystyrene nanoparticles; CPC, colloidal photonic crystal; GO, graphene oxide; FAM, 6-carboxyfluorescein).

High-throughput ultra high performance liquid chromatography combined with mass spectrometry approach for the rapid analysis and characterization of multiple constituents of the fruit of Acanthopanax senticosus (Rupr. et Maxim.) Harms.

Acanthopanax senticosus (Rupr. et Maxim.) Harms, a traditional Chinese medicine, has been widely used to improve the function of skeleton, heart, spleen and kidney. This fruit is rich in nutrients, but the chemical constituents of Acanthopanax senticosus fruit are still unclear. A rapid method based on ultra high performance liquid chromatography with time-of-flight mass spectrometry was developed for the compound analysis of Acanthopanax senticosus fruit in vitro and in vivo. In this study, the Acanthopanax senticosus fruit could significantly increase the weight of immune organs, promote the proliferation of lymphatic T cells, regulate the lymphatic B cell function, and decrease the ability of natural killer cells. A total of 104 compounds of Acanthopanax senticosus fruit including lignans, flavones, triterpenoidsaponins, phenolic acids, and other constituents were identified. Among them, seven chemical compounds were reported for the first time in the Acanthopanax senticosus fruit. Compared with the serum sample of blank and dosed samples, 24 prototype compositions were characterized. The results of our experiment could be helpful to understand the complex compounds of Acanthopanax senticosus fruit in vitro and in vivo for further pharmacological activity studies.

Characterization of the multiple components of Acanthopanax Senticosus stem by ultra high performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry.

Acanthopanax Senticosus Harms. has been used widely in traditional Chinese medicine for the treatment of chronic bronchitis, neurasthenia, hypertension and ischemic heart disease. However, the in vivo constituents of the stem of Acanthopanax Senticosus remain unknown. In this paper, ultra high performance liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometry and the MarkerLynx(TM) software combined with multiple data processing approach were used to study the constituents in vitro and in vivo. The aqueous extract from the Acanthopanax Senticosus stem and the compositions in rat serum after intragastric administration were completely analyzed. Consequently, 115 compounds in the aqueous extract from Acanthopanax Senticosus stem and 41 compounds absorbed into blood were characterized. Of the 115 compounds in vitro, 54 were reported for first time, including sinapyl alcohol, sinapyl alcohol diglucoside, and 1-O-sinapoyl-ß-D-glucose. In the 41 compounds in vivo, 7 were prototype components and 34 were metabolites which were from 21 components of aqueous extract from Acanthopanax Senticosus stem, and the metabolic pathways of the metabolites were elucidated for first time. The results narrowed the range of screening the active components and provided a basis for the study of action mechanism and pharmacology.

Development of database of real-world diesel vehicle emission factors for China.

A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China, NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT (Computer Programmer to calculate Emissions from Road Transport) and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5 (Highway Vehicle Particulate Emission Modeling Software) models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent, which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-based models will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models.

Analysis of Pharmacy Student Perceptions and Attitudes Toward Web 2.0 Tools for Educational Purposes.

Background: The use of Wikis, blogs, and podcasts can engage students in collaborative learning, allow peer feedback, and enhance reflective learning. However, no survey to date has been performed across all professional years of pharmacy students in order to obtain a comprehensive overview of student perceptions. Objectives: To identify the familiarity of pharmacy students with Web 2.0 resources available for medical education, and what barriers exist. Methods: This study surveyed students enrolled in the professional program of a US-accredited pharmacy school to assess their knowledge and current use of available online resources and attitudes toward the use of Web 2.0 technologies for educational purposes. Results: Of the 836 surveys distributed, 293 were collected and analyzed (35.0% response rate). Students reported using the following Web 2.0 technologies in the didactic and experiential settings, respectively: Wikipedia (88%, 70%), YouTube (87%, 41%), Khan Academy (40%, 5%), and medical or scientific blogs (25%, 38%). Although these technologies were more commonly used in the classroom, students agreed or strongly agreed such resources should be used more often in both the didactic (n = 187, 64%) and experiential settings (n = 172, 59%). The barriers associated with the use of Web 2.0 in both the didactic and experiential settings that were ranked highest among students included accuracy and quality of information and lack of familiarity among faculty members and preceptors. Conclusion: Pharmacy students across all professional years actively use Web 2.0 tools for educational purposes and believe that opportunities exist to expand use of such technologies within the didactic and experiential settings.

Identification of 3-chloro-1,2-propandiol using molecularly imprinted composite solid-phase extraction materials.

A novel molecularly imprinted material based on silica microparticles was synthesized by surface polymerization with 3-chloro-1,2-propandiol (3-MCPD) as a template molecule. The molecularly imprinted polymer (MIP) was characterized by infrared spectroscopy and scanning electron microscopy. The adsorption of 3-MCPD by MIP was measured by gas chromatography with electron capture detection (GC-ECD) and an equilibrium binding experiment. Scatchard analysis revealed that the maximum apparent binding capacities of the MIP and non-imprinted polymer (NIP) were 67.64 and 23.31 µmol/g, respectively. The new adsorbent was successfully used in solid-phase extraction (SPE) to selectively enrich and determine 3-MCPD in soy sauce samples. The MIP-SPE column achieves recoveries higher than 92.7% with a relative standard deviation of less than 1.83%. The MIP-SPE-GC protocol improved the selectivity and eliminated the effects of template leakage on quantitative analysis and could be used for the determination of 3-MCPD in other complex food samples.

Construction safety influencing factor analysis of bridge-erecting machines based on structural equation modeling.

To reduce the frequency of bridge-erecting machine accidents and ensure construction safety, it is necessary to correctly understand the factors affecting the construction safety of bridge-erecting machines and their relative importance. Through a literature review and a field investigation, 15 factors were identified affecting the construction safety of bridge-erecting machines. Then, questionnaire survey items are established. Structural equation modeling (SEM) was used to build the relationship model among the factors. The model included four aspects-human, mechanical equipment, and environmental safety and management-to discuss the influence of each factor on the safety of bridge-erecting machine construction. Additionally, the relationships between the influencing factors is studied and analyzed. The results show that human, mechanical equipment, and environmental safety and management capacity have significant normal influences on the construction safety of bridge-erecting machines. Human safety has the greatest influence on the construction safety of bridge-erecting machines, followed by management capacity, mechanical equipment safety, and environmental safety. In addition, the four influencing factors have a certain degree of mutual influence.

A dynamic prediction model of landslide displacement based on VMD-SSO-LSTM approach.

Addressing the limitations of existing landslide displacement prediction models in capturing the dynamic characteristics of data changes, this study introduces a novel dynamic displacement prediction model for landslides. The proposed method combines Variational Mode Decomposition (VMD) with Sparrow Search Optimization (SSO) and Long Short-Term Memory (LSTM) techniques to formulate a comprehensive VMD-SSO-LSTM model. Through the application of VMD, the method dissects cumulative displacement and rainfall data, thereby extracting distinct components such as trend, periodicity, and fluctuation components for displacement, as well as low-frequency and high-frequency components for rainfall. Furthermore, leveraging Gray Correlational Analysis, the interrelationships between the periodic component of displacement and the low-frequency component of rainfall, as well as the fluctuation component of displacement and the high-frequency component of rainfall, are established. Building upon this foundation, the SSO-LSTM model dynamically predicts the interrelated displacement components, synthesizing the predicted values of each component to generate real-time dynamic forecasts. Simulation results underscore the effectiveness of the proposed VMD-SSO-LSTM model, indicating root-mean-square error (RMSE) and mean absolute percentage error (MAPE) values of 1.2329 mm and 0.1624%, respectively, along with a goodness of fit (R2) of 0.9969. In comparison to both back propagation (BP) prediction model and LSTM prediction model, the VMD-SSO-LSTM model exhibits heightened predictive accuracy.

Assessment of identification performance for high emission heavy-duty diesel vehicles by means of remote sensing.

To improve the accuracy of detecting high NO (nitric oxide) emissions from heavy-duty diesel vehicles (HDDV) by remote sensing (RS), the emissions of one HDDV complied with China V regulation and one HDDV complied with China VI regulation at constant speeds, with and without after-treatment devices, are tested by a portable emission measurement system (PEMS) and RS. The optimized measurement procedures for detecting high NO emissions from China V and China VI HDDVs by RS are summarized. The correlation of RS and PEMS data shows that the ratio of NO to CO2 (carbon dioxide) is a more appropriate RS measurement than NO concentration alone for identifying high emitters, although NO concentrations of 600 ppm and 100 ppm can be used as a basis for distinguishing between China V and China VI HDDVs, respectively. When the NO/CO2 ratio is >200 × 10-4 and 25 × 10-4, identifying China V and China VI HDDV high emitters, respectively, is possible. Additionally considering the vehicle speed can reduce the high emitter identification error rate, and excluding data where vehicle acceleration is less than -0.1 m/s2 can further improve identification accuracy. Four new high-emitter identification methods based on different combinations of measurements are shown to improve identification efficiency with only small increases in identification error. This study provides evidence to support the future development of high-precision RS methodologies for identifying high-emission vehicles.