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Providing high-quality public transport services and enhancing passenger experiences require efficient urban rail transit connectivity; however, passengers’ perceived transfer distance at urban rail transit stations may differ from the actual transfer distance, resulting in inconvenience and dissatisfaction. To address this issue, this study proposed a novel machine learning framework that measured the perceived transfer distance in urban rail transit stations and analyzed the significance of each influencing factor. The framework introduced the Ratio of Perceived Transfer Distance Deviation (R), which was evaluated using advanced XGBoost and SHAP models. To accurately evaluate R, the proposed framework considered 32 indexes related to passenger personal attributes, transfer facilities, and transfer environment. The study results indicated that the framework based on XGBoost and SHAP models can effectively measure the R of urban rail transit passengers. Key factors that affected R included the Rationality of Signs and Markings, Ratio of Escalators Length, Rationality of Traffic Organization outside The Station, Ratio of Stairs Length, and Degree of Congestion on Passageways. These findings can provide valuable theoretical references for designing transfer facilities and improving transfer service levels in urban rail transit stations.

Probiotics have been associated with clinical infections, toxicity, and antimicrobial resistance transfer, raising public concerns. Probiotic enterococci are emerging food risks as opportunistic pathogens, yet little attention has been paid to them. Herein, we collected 88 enterococcal isolates from probiotic products used for humans, companion animals, livestock, and aquaculture. Results showed that all 88 probiotic enterococcal isolates harbored diverse virulence genes, multiple antimicrobial resistance genes, and mobile genetic elements. Notably, 77 isolates were highly resistant to gentamicin. Representative enterococcal isolates exerted toxic activities in both in vitro and in vivo models. Collectively, our findings suggest that probiotic enterococci may be harmful to hosts and pose a potential threat to public health.

Foodborne diseases have been witnessing a constant rising trend worldwide, mainly caused by pathogenic microorganisms, such as Bacillus spp., posing a direct threat to public health. The purpose of this study was to evaluate the biological risk of foodborne and probiotic Bacillus spp. in Beijing markets. A total of 55 Bacillus isolates, including 29 B. cereus, 9 B. licheniformis and 7 B. subtilis, mostly found in dairy products (32.7%), were recovered from 106 samples and identified by matrix-assisted laser desorption/ionization mass spectrometry and polymerase chain reaction methods. The susceptibility towards 16 antibiotics was determined using a broth microdilution method. Bacillus showed a high level of resistance to florfenicol (100%), lincomycin (100%), tiamulin (78.2%) and ampicillin (67.3%), while they were all susceptible or intermediate to vancomycin and rifampin. Additionally, we obtained the whole genome of 19 Bacillus strains using high-throughput sequencing, and the rates of resistance genes van, fosB, erm and tet were 57.9%, 57.9%, 21.1% and 26.3%, respectively. Moreover, 100%, 9.1%, 45.5% and 100% of these isolates carried virulence genes nhe, hbl, cytK and entFM, respectively. Lastly, 60% Bacillus strains were positive in hemolysis tests, and 3 B. licheniformis strains displayed an inhibitory activity on the growth of S. aureus ATCC 29213 using agar overlay technique. Our study outlines the characteristics of foodborne Bacillus spp. and provides information for the monitoring of food safety.

The stability and effective functioning of a power grid depends upon the reliability as well as safety prospects of a transformer which is the principal component of the power system. The natural oil circulation in the oil-immersed transformer drifts the oil flow by the change in the density which is again caused by the change in temperature. But the pressure is comparatively low with respect to the oil pump causing the lower down of velocity which in turn dissipates unimpressionable heat. In this paper, a noble attempt has been made to build a natural oil circulation layer-type winding transformer based on a fluid-solid coupling heat transfer model pertaining to the internal temperature field and flow field by using the fluid mechanics’ simulation software. In the next stage, the authors have analyzed the temperature distribution, hot spot, position condition of the variable winding, the horizontal the oil channel width as well as the temperature of the winding transformer. The paper is of great significance as it examines the influence of the flow characteristics of oil channel on the winding temperature distribution. The outcome can significantly improve the structure of heat dissipation and the operating environment of the transformer.

Female, especially for pregnant female, are vulnerable to psychological stress. The morphology and metabolism of the maternal intestine are both obviously changed during pregnancy, thus making intestinal health status more fragile under psychological stress. The aim of the present study was to investigate the role of CRH and CRHR1 in the pregnant maternal intestine under psychological stress, thus exploring the mechanism of psychological stress in the pregnant maternal intestine. Bama miniature pigs were divided into the control and restraint stress groups from the first day of pregnancy. After restraint stress treatment for 18 consecutive days (D18), the plasma, duodenum, jejunum, ileum and colon were collected for study. Pregnant Bama miniature pigs subjected to restraint stress had significantly elevated CRH, adrenocorticotropic hormone (ACTH) and cortisol (COR) levels in plasma. Consistent with the increase in CRH levels, we observed enhanced oxidative stress levels in the intestine, which resulted in intestinal mucosal injury, including impaired intestinal morphology, a reduced number of goblet cells and proliferating cell nuclear antigen-positive cells, decreased expression of MUC2 and tight junctions, and elevated expression of CRHR1 and caspase-3. Moreover, exogenous CRH could directly promote IPEC-J2 cell apoptosis and influence its cell cycle (S and G2 phase) through CRHR1, and antalarmin could alleviate this phenomenon. Therefore, our results illustrated that the intestinal dysfunction of pregnant Bama miniature pigs was caused by restraint stress, and these changes were associated with the enhanced expression of CRH and CRHR1 in the intestine.

Oxidative stress (OS) is involved in various reproductive diseases and can induce autophagy and apoptosis, which determine the different fates of cells. However, the sequence and the switch mechanism between autophagy and apoptosis are unclear. Here, we reported that chronic restraint stress (CRS) induced OS (decreased T-AOC, T-SOD, CAT and GSH-Px and increased MDA) and then disturbed the endocrine environment of sows during early pregnancy, including the hypothalamic-pituitary-ovarian (HPO) and the hypothalamic-pituitary-adrenal (HPA) axes. Meanwhile, after CRS, the KEAP1/NRF2 pathway was inhibited and attenuated the antioxidative ability to cause OS of the endometrium. The norepinephrine (NE) triggered β2-AR to activate the FOXO1/NF-κB pathway, which induced endometrial inflammation. CRS induced the caspase-dependent apoptosis pathway and caused MAP1LC3-II accumulation, SQSTM1/p62 degradation, and autophagosome formation to initiate autophagy. Furthermore, in vitro, a cellular OS model was established by adding hydrogen peroxide into cells. Low OS maintained the viability of endometrial epithelial cells by triggering autophagy, while high OS induced cell death by initiating caspase-dependent apoptosis. Autophagy preceded the occurrence of apoptosis, which depended on the subcellular localization of FOXO1. In the low OS group, FOXO1 was exported from the nucleus to be modified into Ac-FOXO1 and bound to ATG7 in the cytoplasm, which promoted autophagy to protect cells. In the high OS group, FOXO1 located in the nucleus to promote transcription of proapoptotic proteins and then induce apoptosis. Here, FOXO1, as a redox sensor switch, regulated the transformation of cell autophagy and apoptosis. In summary, the posttranslational modification of FOXO1 may become the target of OS treatment.

A filtering dielectric resonator antenna (FDRA) with wide bandwidth is investigated in this paper. The TE210 mode of the substrate integrated waveguide (SIW) cavity is utilized to feed stacked rectangular dielectric resonators (DRs) for improvement of the gain selectivity. Then, three resonant modes as TE 110 mode, TE 210 mode of SIW and TE 111 mode of DRs are excited. By elaborately arranging the feeding structure and the stacked DRs with different relative permittivity, we can broaden the impedance bandwidth. Three radiation nulls near the lower and higher edges of the gain passband are introduced to improve the gain selectivity. Simulated results of the reflection coefficient, antenna gain and radiation pattern are provided with impedance bandwidth of 19% and average gain of 5.64 dBi within passband.

To extend the spectral response region of squaraine dye (SQ)-sensitized solar cell, eosin Y (EY) is encapsulated in the SQ-sensitized nanocrystalline thin film. EY is first adsorbed on nanocrystalline TiO2 thin film (n-TiO2), then a thin layer of EY contained ZnO (EY-ZnO) is electrodeposited, and SQ dye is finally sensitized to form two dye-sensitized nanocrystalline thin film with a structure of n-TiO2/EY/EY-ZnO/SQ. There is a perfect spectral overlap between the emission of EY and the absorption of SQ; EY as an energy donor simultaneously transfers both electron and hole to the energy acceptor SQ according to the Forster resonance energy transfer (FRET) process. EY shifts the spectral response edge of SQ-sensitized solar cell toward blue from 550 to 450 nm through the FRET process in this new structure. Two dye-sensitized nanocrystalline thin film demonstrates a significant enhancement in light harvesting and photocurrent generation due to the FRET process. The thickness of the EY-ZnO thin layer and spectral overlap between emission of donor dye and absorption of acceptor dye are two important factors that affect the FRET process between EY and SQ in the structure of n-TiO2/EY/EY-ZnO/SQ.

Background: Helicobacter pylori (Hp) is a unipolar, multi-flagellate, spiral,Gram-negative bacterium that is the only stomach bacterium found in humans.Hp is the leading cause of digestive tract disease and can cause stomach diseases, such as chronic gastritis, peptic ulcer, gastric cancer and gastric mucosa-associated lymphoma. Clinical studies have shown that Hp infection rates are significantly higher in patients with hyperlipidaemia than they are in non-hyperlipidaemic patients. In addition,many studies have shown that the serum vitamin D3 levelsare reduced in patients with obesity and hyperlipidaemia.Lower serum vitamin D3 levels diminish the role of fat cells in storing fat;as a result,fat is released into the bloodstream,leading to elevated blood lipid levels.However, a specificmechanism has not been proposed to explain how VD3 can reduce HP infection in patients with hyperlipidaemia by lowering blood lipids. Methods real-time PCR was used to detect the expression of gastrin in VDR, insign-2 and gastric tissues of mice in each group. The expression of jak, stat 3, cox2 and lkba protein in gastric tissue of mice was detected by western blotting. We also detected the expression of IL-6 and IL-8 in the gastric tissue of mice by Elisa method. The liver tissues of each group were stained with HE to observe the balloon-like changes of liver tissue, and the gastric tissues of mice in each group were stained by HE. The degree of gastritis in each group of mice. Conclusions In this article, we conducted animal experiments using VD3 as an intervention in hp-infected mice and then examined molecular changes in the VDR/Insig-2/SREBP-2 pathways in the mouse liver, the serum cholesterol levels, and the JAK-STAT3 and NF-ĸB pathways.Vitamin D3 further reduced the gastric mucosa cholesterol level,destroyed lipid rafts,and reduced assembly of IL-6 receptor subunits by lowering the circulating cholesterol levels, thereby blocking the JAK-STAT3 signalling pathway. Infection of the gastric mucosa by CagA-positive Helicobacter pylori reduced gastrin secretion and inhibited COX2 expression. Moreover, NF-κB activation and inflammatory cytokine expression were inhibited by blocking the JAK-STAT3 signalling pathway. Furthermore, the degree of infection of the gastric mucosal tissue was reduced.

To investigate the effects of equal concentration of Helicobacter pylori suspension on gastric mucosal infection in mice by different gavage methods. Methods: Six-week-old male C57BL/6 mice were infected by a suspension of Brucella broth containing the same amount of NCTC11637 Helicobacter pylori suspension by A, B, C, and D methods. For method A, the mice were intragastrically administered with Helicobacter pylori suspension (0.2 mL per mouse), once two day for 5 times; for method B, the mice were intragastrically administered with Helicobacter pylori (0.2 mL per mouse) once a day for 5 times; for method C, the mice were perfused with 0.4 mL per mouse of Helicobacter pylori suspension on the first day, then once a day and 0.2 mL per mouse for 3 times; for method D, the mice were administrated with 0.4 mL per mouse Helicobacter pylori suspension on the first day, 0.2 mL per mouse every other day for 3 times. For method E, the mice received equal amounts of normal saline. The mice were killed at 2, 4, and 6 weeks after gavage. The gastric mucosa was detected by rapid urease test for Helicobacter pylori infection, and gastric mucosa was taken for HE staining to observe the degree of infection. Results: After 2 weeks of gavage, the infection rates of the mice in A, B, C, and D group were 33.3%, 50.0%, 66.7%, and 33.3%, respectively. The degree of inflammation infection was as following order: C groupB groupD groupA groupE group. The infection rates of mice after 4 weeks of gavage in the A, B, C, and D groups were 50.0%, 83.3%, 83.3%, and 66.7%, respectively. The degree of inflammation infection was as following order: C groupB groupD groupA groupE group. After 6 weeks of gavage, the infection rate in A, B, C, and D groups was 100%, while the degree of inflammation infection was as following order: C groupD groupB groupA groupE group. Conclusion: At the acute stage of Helicobacter pylori infection, different gavage methods show different infection rates in mice, and the degree of inflammation is different. At the chronic stage, different gavage methods display the same infection rate in mice with different degree. The gavage method that 0.4 mL Helicobacter pylori suspension on the first day, then once a day and 0.2 mL for 3 times is most conducive to Helicobacter pylori colonization in the gastric mucosa of mice. This method can induce the the most seriou inflammatory infection and is beneficial to the successful establishment of the Helicobacter pylori infection model.目的：探讨等量幽门螺杆菌不同灌胃方法对小鼠幽门螺杆菌的感染率及小鼠胃黏膜感染幽门螺杆菌程度的影响。方法： 将含等量NCTC11637幽门螺杆菌的布氏肉汤混悬液通过A，B，C，D 4种方法感染6周龄的雄性 C57BL/6小鼠。A方法用幽门螺杆菌悬液0.2 mL/只灌胃小鼠，隔天1次，共5次。B方法用幽门螺杆菌悬液0.2 mL/只灌胃小鼠，每天1次，连续5次。C方法第1天用幽门螺杆菌悬液灌胃小鼠0.4 mL/只，以后连续3 d每天灌胃1次，每次0.2 mL/只。D方法第1天用幽门螺杆菌悬液灌胃小鼠0.4 mL/只，以后隔天灌胃1次，每次0.2 mL/只，共3次。E方法用等量生理盐水灌胃小鼠。灌胃后第2，4，6周处死小鼠，其胃黏膜组织用快速尿素酶检测是否有幽门螺杆菌感染，并取胃黏膜组织进行HE染色，观察胃黏膜组织的感染程度。结果：2周后A，B，C，D组小鼠的感染率分别为33.3%， 50.0%，66.7%，33.3%；炎症的感染程度C方法B方法D方法A方法E方法。4周后A，B，C，D组小鼠的感染率分别为50.0%，83.3%，83.3%，66.7%；炎症的感染程度C方法B方法D方法A方法E方法。6周后A，B，C，D组小鼠的感染率均为100%；炎症的感染程度C方法D方法B方法A方法E方法。结论：在幽门螺杆菌急性感染期，灌胃方法不同小鼠的感染率不同，炎症程度不同；在幽门螺杆菌的慢性感染期，灌胃方法不同小鼠的感染率相同，感染的炎症程度不同。采用第1天灌0.4 mL，以后连续3 d每天1次，0.2 mL/次的灌胃方法最有利于幽门螺杆菌在小鼠胃黏膜定植，感染炎症程度最严重，有利于幽门螺杆菌感染模型的成功建立。.

Pedestrian violations pose a danger to themselves and other road users. Most previous studies predict pedestrian violation behaviors based only on pedestrians’ demographic characteristics. In practice, in addition to demographic characteristics, other factors may also impact pedestrian violation behaviors. Therefore, this study aims to predict pedestrian crossing violations based on pedestrian attributes, traffic conditions, road geometry, and environmental conditions. Data on the pedestrian crossing, both in compliance and in violation, were collected from 10 signalized intersections in the city of Jinhua, China. We propose an illegal pedestrian crossing behavior prediction approach that consists of a logistic regression model and a Markov Chain model. The former calculates the likelihood that the first pedestrian who decides to cross the intersection illegally within each signal cycle, while the latter computes the probability that the subsequent pedestrians who decides to follow the violation. The proposed approach was validated using data gathered from an additional signalized intersection in Jinhua city. The results show that the proposed approach has a robust ability in pedestrian violation behavior prediction. The findings can provide theoretical references for pedestrian signal timing, crossing facility optimization, and warning system design.

SEM and XRD of the ZIF-67 derived thin films

In this paper, an ultra-light and high electromagnetic shielding effectiveness (SE) composite material based on melamine foam with its skeleton metallized was prepared via electroless silver plating techniques. Salt-based colloid palladium was applied as the activator to modify the foam skeleton. X-ray photoelectron spectroscopy was used for tracking the Pd activated process. The effects of silver plating time, dynamic and static electroless plating conditions on the surface morphology, electrical and EMI shielding properties were investigated. The silver content in the foams subjected to electroless plating for different time was measured by thermo gravimetric analysis. Crystal structure of the silver nanoparticles was examined by the X-ray diffraction (XRD). Results show that a dense, uniform, consecutive silver layer forms on the surface of foam skeleton with the electroless silver plating time increases. A relatively dynamic electroless plating conditions do not help to construct a complete silver layer without cracks. The conductivity and SE of the foams is enhanced with the extension of silver plating time. The foam just containing 63.5 wt% silver achieves a minimum resistivity of 0.06 Ω cm and a SE of above 90 dB at the frequency range of 0.05–18 GHz. The foam prepared under a dynamic electroless plating condition exhibits lower SE than that under a static electroless plating condition. The XRD pattern shows the deposited silver coating exists as a typical face-centered cubic crystalline structure and the average crystal size is 14.4 nm. All results imply that such conductive melamine foam exhibits excellent electrical and EMI shielding properties, which can be used in a broad application range.

A novel crawling in-pipe robot was designed to improve the adaptive ability with self-locking principle applied. In the moving, the robot was adaptable to horizontal, vertical and bending pipes with different diameters and sections without exerting additional pressure to the shell. The robot used a telescopic umbrella stand as a basic structure. The force of telescopic mechanism, self-locking principle of supporting mechani sm and shell were deduced from design requirements. The design of supporting and coupling mechanism was completed. The relationship between screw rod thrust and parallelogram driving force was established. A prototype was made and tested according to the suggested design methods. The results show that the robot with powerful traction, good self-locking performance and smooth passage through curve can move forward in the pipe with 90~150 mm inner diameter.

In this article, a high electromagnetic interference shielding effectiveness (EMI SE) polymer composite with multiple conductive networks was manufactured via combining a conductive foam, low loading multi-wall carbon nanotubes (MCNTs), bisphenol A-type epoxy resin NPEL-128, curing agent polyamide Versamid 140, and reactive diluent glycol diglycidyl ether. The conductive foam was prepared using melamine foam (BasotectW®) through an electroless silver plating process. The resistivity of the foam and each composite system were measured by a four-point probe resistivity determiner. The morphology of the composites was observed by scanning electron microscope and the silver contents on the foam skeletons were measured by thermal gravimetric analysis. Dynamic mechanical analysis was employed to studying the mechanical properties and structural changes of the composites. A very low minimum value of 0.06 Ω · cm was obtained by the foam. Due to its intrinsic structure, multiple networks composites exhibited a lower resistivity value which was nearly 5 ~ 8 orders of magnitude lower than that of CNTs/epoxy nanocomposite at the same CNTs loading. The EMI SE of each composite system was measured by a vector network analyzer in 0.2 ~ 18 GHz. The SE value of the multiple networks composites, only containing 2 wt % CNTs and 3.3 wt % silver, reached a maximum of 88 dB and an average of 68 dB. All results above showed that the synergistic effect from the multiple conductive networks was contributed to enhancing the conductivity and EMI SE of the composites.