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The composition of Fe–30Mn–11Al–12Ni–1C lightweight alloy steels was designed and the effect of laser power on the microstructure and properties of the lightweight steels formed by laser powder bed fusion (LPBF) was studied in this paper. The results show that the relative density of lightweight steel samples formed by LPBF increases gradually with the increase of laser power at a constant scanning speed, and the relative density of samples formed at 120 W is the highest, reaching 99.2%. Under the different laser power, the unfused regions appear in the plane parallel to the construction direction (XOY), and the cracks appear in the plane perpendicular to the construction direction (XOZ). The defect types on the XOY observation plane are different from the XOZ observation plane, which are reflected in the following aspects: XOY plane has a large number of unfused pores, spherical powders, and large holes, and with the increase of laser power, the unfused defects and hole areas gradually decrease, and the spherical powders disappear; the defects on the XOZ plane are mainly holes and cracks, with the increase of laser power, the holes decrease gradually, but the crack width increases. The hardness of samples shows anisotropy, and the anisotropy gradually decreases with the increase of laser power. The hardness on the XOZ plane does not change obviously with laser power, but it is higher than the XOY plane. The microhardness on the XOY plane changes greatly, because the laser power increases and the effect of defects is reduced. When the laser power is 120 W, the hardness on the XOZ plane reaches the maximum as HV0.2 441.3. With laser power of 90 W and scanning speed of 800 mm·s−1, the yield strength and tensile strength of the formed light steel samples reach the maximum value, which are 800.8 MPa and 825.4 MPa respectively. There is a large amount of the precipitated phase at the grain boundary of the samples, resulting in the low elongation of all the samples, so the plasticity of the LPBF formed light steel is poor.

Objective To investigate the effect of a small amount of leukocyte mixed in platelets on platelet RNA related study, and to further propose a method to remove leukocyte contamination. Methods The collected platelets were divided into groups and then processed. 1) Control group: Cells were collected by direct centrifugation; 2) Centrifuge purification group: Centrifuge with different centrifugal forces to collect precipitated cells and recover suspended cells; 3) Magnetic bead purification group: Remove CD45 positive leukocyte from platelets using magnetic bead method, and recover CD45 negative platelet cells. Total RNA was extracted from the cells, and cDNA was reverse transcribed from the extracted RNA. The fragments of housekeeping gene β-actin, platelet marker ITGA2B and leukocyte marker PTPRC were PCR amplified using cDNA as a template. The results of the PCR amplification were used to determine the influence of leukocyte contamination in platelet mRNA study and the effect of centrifugation purification and magnetic bead purification. Results PTPRC gene could be detected in cDNA from platelet cells obtained by direct centrifugation. PTPRC gene was also detected in cell segments collected from both precipitated and suspended cells after centrifugation under different conditions. But PTPRC was not detected in platelet after removal of CD45 positive cells by magnetic bead. Conclusion A small amount of leukocyte contamination in platelets can interfere with the mRNA study of platelets. The simple centrifugation could not remove the leukocyte contamination in platelets, but the magnetic bead had a better purification effect.

Objective To investigate the serological characteristics and molecular mechanism of an individual with Am phenotype. Methods The sample with ABO blood group discrepancy was confirmed by serological techniques. The full coding and flanking regions of the ABO gene including intron 1 transcription factor binding site were identified through direct sequencing of PCR-amplified products. PCR products of exon 6-7 were validated to isolate the ABO gene haplotypes by cloning and sequencing individual colonies. Bioinformatics software was used to analyze the structure of the mutant protein. Results The serologic characteristics of ABO blood typing showed the rare Am phenotype. The c.467C/T and c.912C/A heterozygous sites in exon 7 were identified by direct sequencing analysis. Further TA cloning and sequencing revealed that the patient carried an ABO* O.01.01 allele and a novel ABO*A allele. The new allele sequence had one nucleotide alteration (C>A) at position 912 on the background of the ABO*A1.02 allele. The new allele sequence has been included in the GenBank database with the entry number JX489776. The c.912C>A mutation was predicted to be “probably damaging” and “deleterious” by PolyPhen2 and PROVEAN algorithms, respectively. The free energy change (ΔΔG) value predicted it to have a destabilizing effect on the GTA protein. Meanwhile, modeling of the 3D structure predicted that the p.S304R amino acid substitution may alter the hydrogen bond of the GTA protein. Conclusion The p.S304R substitution of α-1,3-N-acetylgalactosaminyltransferase gene may reduce the antigen expression owing to a greatly destabilizing effect on the structure and function of the GTA protein.

Objective To construct a radiomic model based on intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) for preoperative prediction of hepatocellular carcinoma (HCC) differentiation and validate its clinical value. Methods Clinical and imaging data of 187 HCC patients who received surgical treatment in the Third Affiliated Hospital of Chongqing Medical University from June 2018 to January 2024 were collected and retrospectively analyzed. According to the postoperative pathological results, they were divided into low-differentiation group (n=58) and non-low-differentiation group (n=129), and randomly divided into the training group (n=149) and the validation group (n=38) with the ratio of 8 ∶2. Univariate analysis was used to assess the clinical indicators related to HCC differentiation, and then a clinical model was constructed. Pyramidimics software was used to extract the radiomic features of IVIM-DWI functional images, and minimum absolute contraction and selection operator logistic regression algorithm were employed to screen those highly correlated indicators with HCC differentiation. Support vector machine (SVM), logistic regression (LR) and random forest (RF) algorithms were utilized to construct different image omics models. SVM algorithm was applied to construct the combined imaging omics and clinical model. The internal verification of the model was carried out by using ten-fold cross-validation. Receiver operating characteristic (ROC) curve, area under the curve (AUC), calibration curve, and decision curve analysis (DCA) were used to evaluate the diagnostic value and clinical benefits of clinical model, radiomic model, and their combination. Results A total of 4 060 radiological features were extracted, and after feature screening and dimensionality reduction, 24 features were finally included to construct the model. Among all models, the predictive performance of the radiomic model and the radiomic-clinical combined model was better than that of the clinical model. In the comparison between the radiomic model constructed by SVM algorithm and the radiomics-clinical combined model, the AUC value was 0.954 (0.908~1.000) for the former model, and was 0.943 (0.905~0.982) for the latter model in the training set, and there was no significant difference between them. In the validation set, the AUC value was 0.807 (0.640~0.975) and 0.876 (0.743~1.000), respectively, with statistical difference between the 2 models (P < 0.05). Calibration curve analysis showed that the radiomic model and the radiomics-clinical combined model had good goodness of fit. DCA indicated that the net benefit was higher and the threshold probability range was larger in both the radiomic model and the radiomics-clinical combined model, and the net benefit of the combined model was larger. Conclusion Both the radiomic model and the combined radiomics-clinical model constructed on the basis of IVIM-DWI functional images can better predict the severity of HCC differentiation before surgery.

Objective To explore the expression of prohibitin (PHB) in tumor tissues and analyze its effect on the prognosis of patients with digestive system malignant tumor (DT) and its mechanism. Methods ① The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) database were used to compare the expression of PHB in tumor tissues and normal tissues.②Five pairs of gastric cancer and adjacent tissues and 5 pairs of colon cancer and adjacent tissues were collected, and RT-qPCR was used to verify the mRNA expression levels.③RT-qPCR and Western blotting were used to verify the differential expression of PHB in normal gastric mucosa cells (GES-1), gastric cancer cells (AGS, MKN45 and HGC27), normal colon cells NCM-460 and human colon cancer cell line SW480.④R language was used to analyze the effect of PHB on the prognosis, tumor microenvironment, tumor mutation burden and microsatellite instability of DT patients.⑤CIBERSORT algorithm was used to study the correlation between PHB expression in tumor tissues and tumor immune cell infiltration.Gene Set Enrichment Analysis (GSEA) was used to explore the biological function of PHB.⑥R language was used to analyze the relationship between PHB and drug sensitivity. Results ① PHB was highly expressed in colon cancer, cholangiocarcinoma, esophageal cancer, liver cancer, rectal cancer and gastric cancer (P < 0.01).②RT-qPCR and Western blotting showed that PHB was highly expressed in the tissues and cell lines of gastric cancer (P < 0.01) and colon cancer (P < 0.01).③The differential expression of PHB was associated with poor prognosis of hepatocellular carcinoma (P=0.002).In cholangiocarcinoma, gastric cancer, pancreatic cancer, liver cancer and esophageal cancer, PHB was positively correlated with tumor mutation burden and microsatellite instability (P < 0.05).④PHB was positively correlated with M2 macrophages in colon cancer (P=0.03).In cholangiocarcinoma, it was positively correlated with activated CD4+ memory T cells (P < 0.05).In esophageal carcinoma, it was positively correlated with activated hypertrophy (P=0.03).It was positively correlated with M0 and M2 macrophages and monocytes in hepatocellular carcinoma (P < 0.05).It was positively correlated with resting dendritic cells, eosinophils and activated CD4+ memory T cells in rectal cancer (P < 0.05).It was positively correlated with M0 macrophages, activated mast cells, neutrophils, resting natural killer cells, activated CD4+ memory T cells and follicular helper T cells in gastric cancer (P < 0.05).⑤PHB was mainly enriched in class I receptors, PPAR and calcium signaling pathways (P < 0.05).⑥ The expression of PHB was positively correlated with the sensitivity of 13 drugs, including ammonafide, prasinolide and abiraterone (P < 0.05). Conclusion The expression of PHB is significantly related to the infiltration of various immune cells in DT and poor prognosis in DT patients, which may become a new biomarker and potential immunomodulatory target of DT.

Objective In view of the continuous growth of energy consumption in metro stations, in order to accurately evaluate their current energy consumption level, tap energy conservation potential and promote energy conservation of buildings, it is necessary to revise the reasonable energy consumption of ventilation and air-conditioning in platform screen door metro stations. Method Based on the principle model of energy consumption, the reasonable energy consumption benchmark for metro stations in various climate areas is established systematically. For the typical cities in different climate areas including cold area, hot summer and cold winter area, hot summer and warm winter area, the energy consumption constraint value and guiding value of the ventilation and air-conditioning system in platform screen door metro stations under basic working conditions are obtained by simulation. In consideration of the climate differences and station services in different areas, the influence intensity of climate conditions, passenger volume, the number of train departures and tunnel length on the energy consumption of metro station ventilation and air-conditioning system is quantitatively analyzed.The revised calculation method is proposed for reasonable energy consumption of ventilation and air-conditioning system in metro stations with platform screen doors under different service conditions and in different cities and different climate areas. Result & Conclusion The annual mean wet-bulb temperature in climate conditions is highly correlated with energy consumption，showing a correlation coefficient R2 of 0.950. The reasonable energy consumption indicator of each climate area increases by 2.2% to 2.9% when the annual total passenger volume increases from 5 million to 11 million,showing little difference among climate areas. The indicator increases by 2.0% to 7.4% when the number of daily total departure trains increases from 140 to 310 pairs, showing obvious difference between different climate areas.The indicator of stations with a 1 200 m long tunnel is 1.5% to 4.9% higher than that of stations with a 800 m long tunnel,showing obvious differences between different climate areas.

6061 aluminum matrix composites added by 3% diamond particles (mass fraction) were prepared by laser powder bed fusion (LPBF). The microstructure, relative density, and tensile properties of the 3%diamond/6061 aluminum matrix composites were characterized and analyzed by optical microscope, scanning electron microscope, X-ray diffractometer, electronic densitometer, and electronic universal testing machine. Results show that the diamond reacts with the Al matrix, generating the needle-like Al4C3 phase, which deposits in the α-Al matrix. Those formed Al4C3 increases dislocations at the grain boundaries, enhances the materials’ strength, and delays the failure to fracture. The addition of diamond facilitates the elimination of thermal cracks, but the porous defects remain in 6061 aluminum alloys. The lower scanning speed extends the contact duration between the laser spot and the processed material, leading to the graphitization of the added diamond and the partial evaporation of the Al matrix. Thus, the internal defects exist, exhibiting the low densification of the composite (relative density 97%). The addition of diamond significantly increases the tensile strength of the LPBF formed diamond/6061 aluminum matrix composites, and the ultimate tensile strength reaches the maximum value of 244.2 MPa, the yield strength is 211.6 MPa, and the elongation is 2.1%, respectively, when the laser power is 350 W and the scanning speed is 800 mm·s−1.

Considering the effects of time-varying load, time-varying excitation, longitudinal stiffness, radial stiffness and bending stiffness of each pulley, the dynamic analysis model of the inner and outer engine front-end accessory drive system is established by Simdrive software. The static characteristics of the system are evaluated. Galerkin method is used to discretize the system space, the implicit multi-step method is used to solve the dynamic characteristics of the system under acceleration conditions, and the influencing factors of the accessory pulley speed fluctuation, tension fluctuation and belt-pulley slip characteristics are obtained. Based on the analysis results, an improvement plan is proposed to appropriately increase the initial tension and the crankshaft wheel wrap angle, and add an automatic tensioner at the No.2 idler gear. The comparison analysis shows that the dynamic characteristics of the engine front-end accessory drive system are improved effectively when adding automatic tensioner.

Background: The Chinese herbal compound Lian-Gui-Ning-Xin-Tang (LGNXT), composed of 9 herbs, has a significant antiarrhythmic effect. Previous studies have confirmed that preventing intracellular Ca2+ overload and maintaining intracellular Ca2+ homeostasis may be the important antiarrhythmic mechanisms of LGNXT. Recent studies are focused on elucidating the mechanisms and pharmacodynamic substances of LGNXT. Purpose: 1) To investigate the antiarrhythmic mechanisms of LGNXT; 2) to explore the association of pharmacodynamics (PD) and pharmacokinetics (PK) of the potential pharmacodynamic substances in LGNXT to further verify the mechanisms of action. Methods: First, pharmacodynamic studies were conducted to determine the effect of LGNXT in arrhythmia at the electrophysiological, molecular, and tissue levels, and the “effect–time” relationship of LGNXT was further proposed. Next, an HPLC-MS/MS method was established to identify the “dose–time” relationship of the 9 potential compounds. Combining the “effect–time” and “dose–time” curves, the active ingredients closely related to the inhibition of inflammation, oxidative stress, and energy metabolism were identified to further verify the mechanisms and pharmacodynamic substances of LGNXT. Results: Pretreatment with LGNXT could delay the occurrence of arrhythmias and reduce their duration and severity. LGNXT exerted antiarrhythmic effects by inhibiting MDA, LPO, IL-6, and cAMP; restoring Cx43 coupling function; and upregulating SOD, Ca2+-ATPase, and Na+-K+-ATPase levels. PK-PD association showed that nobiletin, methylophiopogonanone A, trigonelline, cinnamic acid, liquiritin, dehydropolisic acid, berberine, and puerarin were the main pharmacodynamic substances responsible for inhibiting the inflammatory response in arrhythmia. Methylophiopogonanone A, dehydropalingic acid, nobiletin, trigonelline, berberine, and puerarin in LGNXT exerted antiarrhythmic effects by inhibiting oxidative stress. Dehydropalingic acid, berberine, cinnamic acid, liquiritin, puerarin, trigonelline, methylophiopogonanone A, nobiletin, and tetrahydropalmatine exerted antiarrhythmic effects by inhibiting the energy-metabolism process. Conclusions: LGNXT had a positive intervention effect on arrhythmias, especially ventricular tachyarrhythmias, which could inhibit inflammation, oxidative stress, and energy metabolism; positively stabilize the structure, and remodify the function of myocardial cell membranes. Additionally, the PD–PK association study revealed that methylophiopogonanone A, berberine, trigonelline, liquiritin, puerarin, tetrahydropalmatine, nobiletin, dehydropachymic acid, and cinnamic acid directly targeted inflammation, oxidative stress, and energy metabolism, which could be considered the pharmacodynamic substances of LGNXT. Thus, the antiarrhythmic mechanisms of LGNXT were further elucidated.

A three-dimensional finite element thermal model was established, combined with the finite element software ANSYS, and the simulation of applying a Gaussian heat source and the printing process of WC-12Co cemented carbide was achieved with the use of APDL commands and the birth-death unit method, and the temperature field distribution of WC-12Co cemented carbide in the laser powder bed fusion (LPBF) shaping process was finally obtained, and the effects of different process parameters (laser power, scanning speed) on its temperature field distribution and melt pool characteristics were investigated. The results show that the forming process of WC-12Co cemented carbide in LPBF process can be effectively simulated by using finite elements. In addition, the isotherms located at the front of the heat source are denser than those at the tail, with a larger temperature gradient; and the temperature in the center of the melt pool at the terminal edge of the scanning path is the highest. As the laser power increases and the scanning speed decreases, the width, depth and length of the molten pool increase accordingly. Relevant experiments were used to analyze the effect of different process parameters on grain size, and it is found that the grain size decreases with the increase of scanning speeds and increaseds with the increase of laser power; but too high laser power can cause certain thermal cracking phenomenon.

Objective To investigate whether sarcopenia before concurrent chemoradiotherapy is prone to grade≥3 acute adverse reactions (AAR) and shorten survival in patients with advanced esophageal squamous cell carcinoma (ESCC). Methods Data of advanced patients with pathologically diagnosed ESCC and CCRT (FP regimen) from August 2018 to July 2022 were reviewed retrospectively.Skeletal muscle mass and body composition were measured using pre-treatment CT images, and patients were divided into sarcopenia and non-sarcopenia groups.Grade≥3 AAR was diagnosed based on CTCAE5.0 and acute radiation injury criteria of the US RTOG.Risk factors for developing grade≥3 AAR were analyzed, and survival rates were calculated by Kaplan-Meier method. Results Among 132 patients with ESCC (87 in the sarcopenia group and 45 in the non-sarcopenia group), 23(17.4%) experienced grade≥3 AAR.In multivariate regression analysis, independent risk factors for grade ≥3 AAR included the following: sarcopenia (OR: 6.034, 95%CI: 1.206-30.190, P=0.029), decreased SMD (OR: 0.693, 95%CI: 0.492-0.976, P=0.036), decreased SMI (OR: 0.841, 95%CI: 0.721-0.982, P=0.028), and increased FMI (OR: 2.433, 95%CI: 1.194-4.958;P=0.014).The OS rates were 16.01 months (95%CI: 14.89-17.13) in the sarcopenia group and 19.27 months (95%CI: 14.45-24.09) in the non-sarcopenia group (χ2=5.326, P=0.021) as well as 14.86 months (95%CI: 11.30-18.42) for patients with grade≥3 AAR and 16.67 months (95%CI: 14.91-18.43) for patients with grade 0-2 AAR (χ2=5.47, P=0.019).Among patients with grade≥3 AAR, the OS rates were 12.13 months (95%CI: 10.15-14.11) in the sarcopenia group and 18.69 months (95%CI: 12.85-21.88) in the non-sarcopenia group (χ2=4.466, P=0.035). Conclusion Sarcopenia, decreased skeletal muscle density, and increased fat mass are important predictors of grade≥3 AAR.The OS of patients with sarcopenia and grade≥3 AAR may be reduced.

Objective: The aim of this study was to investigate the endometrial proteomic profiles of patients with polycystic ovary syndrome (PCOS) with and without insulin resistance (IR). Method of Study: We collected 40 endometrial samples, including PCOS-IR (n = 21), PCOS-non-IR (n = 12), and control (n = 7). Data-independent acquisition (DIA)-based proteomics method is used to identify the expressed proteins among the three groups. The correlation between pregnancy outcomes and identified proteins was analyzed by Lasso regression. Results: A total of 5331 proteins were identified, while 275 proteins were differentially expressed in the PCOS vs. control group and 215 proteins were differentially expressed in the PCOS-IR vs. PCOS-non-IR group. Platelet degranulation, neutrophil degranulation, and very long-chain fatty acid catabolic processes have been found to play important roles in the endometrium of patients with PCOS-IR. Lasso regression analysis found that ACTR1A, TSC22D2, CKB, ABRAXAS2, and TAGLN2 were associated with miscarriage in patients with PCOS. ACTR1A and CKB were higher in the PCOS-IR group and were positively correlated with HOMA-IR (p

Objective To investigate the characteristics of gut microbiome and their associations with lymphocyte subsets and disease activity in patients with ankylosing spondylitis (AS). Methods This study was a retrospective analysis. The subjects of the study were AS patients who were hospitalized in the Second Hospital of Shanxi Medical University from December 2019 to June 2020, as well as gender- and age-matched healthy controls (HCs). The fecal samples were collected, and the V3-V4 variable regions of 16S rRNA gene of gut microbiome were sequenced for bioinformatics analysis. Peripheral venous blood was collected from AS patients to determine peripheral blood lymphocyte subsets and disease activity indicators. Spearman correlation test was used to analyze the correlations between the relative abundances of gut microbiota and peripheral blood lymphocyte subsets as well as disease activity in AS patients. Results A total of 62 AS patients (11 with low disease activity, 26 with high disease activity, and 25 with extremely high disease activity) and 62 healthy people who met the inclusion and exclusion criteria were enrolled. As for α-diversity, ACE and Chao1 indices were lower in AS than in HCs(P < 0.05). Bray curtis distance-based β-diversity analysis revealed significant difference in the microbial community between AS and HCs (P < 0.01). As for the composition of the gut microbiome, Firmicutes, Bacteroidetes, and Proteobacteria were the dominant phyla in the gut microbiota of both groups, but there were differences in the abundance of various bacteria at the phylum and genus levels. In Stamp analysis, fecal microbial communities in AS differed significantly from those in HCs, which were characterized by higher abundances of phylum Proteobacteria and Patescibacteria(all P < 0.05) and a lower abundance of phylum Firmicutes and Fusobacteriota (all P < 0.05). At the genus level, the abundances of Escherichia-Shigella, Klebsiella and Enterococcus were increased while those of Prevotella and Faecalibacterium were decreased in AS patients compared to HCs(all P < 0.05). Spearman correlation analysis showed that the relative abundances of Faecalibacterium, Ruminococcus and Klebsiella in AS patients were significantly positively correlated with disease activity or its related indicators(all P < 0.05). There were positive correlations between Agathobacter and T cell (r=0.302, P=0.017), CD4+T cell (r=0.310, P=0.014), B cell (r=0.292, P=0.021), Th2 cell (r=0.429, P < 0.001), Th17 cell (r=0.288, P=0.023), Streptococcus and B cell (r=0.270, P=0.034), Prevotella and Th1 cell (r=0.279, P=0.028), Th17 cell (r=0.262, P=0.040), CAG-352 and Th1 cell (r=0.283, P=0.030). There were negative correlations between Escherichia-Shigella and Th2 cell(r=-0.261, P=0.040), other Enterobacteriaceae and CD4+T cell (r=-0.255, P=0.046). Conclusions The diversity of gut microbiota is reduced in AS patients. The abundance of pathogenic bacteria in AS patients is increased, which is correlated with changes in peripheral blood lymphocyte subsets and disease activity. Dysbiosis may be involved in the occurrence and development of AS.

Objective To investigate the clinical value of energy spectrum CT volume quantitative parameters in differentiating pathological types of colorectal cancer. Methods The clinical and imaging data of 66 patients (16 cases of mucinous adenocarcinoma and 50 cases of tubular adenocarcinoma) with colorectal cancer confirmed by pathology in our hospital from January 2019 to November 2021 were collected and retrospectively analyzed. The volume parameters and two-dimensional parameters of the tumor, including iodine (water) concentration, water (iodine) concentration and effective atomic number, were measured by different methods of region of interest (ROI) acquisition, and normalized iodine (water) concentration (NIC) was calculated. Student's t test or Mann-Whitney U test was used for comparison between groups, and receiver operating characteristic (ROC) curve was drawn to evaluate the diagnostic efficacy of statistically significant parameters for pathological types of colorectal cancer. Results In terms of energy spectrum volume parameters, iodine (water) concentration, NIC and Eff-Z in arterial and venous phases were significantly different (P < 0.01). The iodine (water) concentration, NIC and Eff-Z of mucinous adenocarcinoma were lower than those of tubular adenocarcinoma. However, in the two-dimensional parameters, only iodine (water) concentration, NIC and Eff-Z in venous phase had significant differences among groups (P < 0.05). The volumetric iodine (water) concentration and NIC in mucinous adenocarcinoma were lower than corresponding two-dimensional parameters. ROC curve showed that the area under the curve of energy spectrum volume parameters was higher than that of two-dimensional parameters. Among them, arterial volume NIC had the highest diagnostic efficiency, with a sensitivity of 82.0% and specificity of 87.5%. Conclusion The quantitative parameters of CT volume of energy spectrum may have greater potential clinical value in differentiating mucinous colorectal adenocarcinoma from tubular adenocarcinoma than two-dimensional parameters.

Tailoring the wavefronts of spoof surface plasmon polaritons (SSPPs) at will, especially with multifunctional integration, is of great importance in near-field photonics. However, conventional SSPP devices suffer from the issues of bulk configurations, limited functionalities, and single operating modes, which are unfavorable for electromagnetic (EM) integration. Here, a novel scheme is proposed to design bifunctional SSPP meta-devices based on the polarization dependent property via satisfying the comprehensive phase distributions and multi-mode momentum matching in a transmission geometry. As proof of the concept, we experimentally demonstrate a bifunctional SSPP meta-device in the microwave regime that can convert incident x- and y-polarized waves to transverse magnetic (TM)-mode SSPP Bessel beams and transverse electric (TE)-mode SSPP focusing beams, respectively. Our findings open a door to achieve near-field manipulation of SSPPs with multi-function and multi-mode integration, which can stimulate the applications of SSPP functional devices, such as near-field sensing, imaging, and on-chip photonics.

Metasurfaces, interacted with artificial intelligence, have now been motivating many contemporary research studies to revisit established fields, e.g., direction of arrival (DOA) estimation. Conventional DOA estimation techniques typically necessitate bulky-sized beam-scanning equipment for signal acquisition or complicated reconstruction algorithms for data postprocessing, making them ineffective for in-situ detection. In this article, we propose a machine-learning-enabled metasurface for DOA estimation. For certain incident signals, a tunable metasurface is controlled in sequence, generating a series of field intensities at the single receiving probe. The perceived data are subsequently processed by a pretrained random forest model to access the incident angle. As an illustrative example, we experimentally demonstrate a high-accuracy intelligent DOA estimation approach for a wide range of incident angles and achieve more than 95% accuracy with an error of less than 0.5° $0.5{}^{\circ}$ . The reported strategy opens a feasible route for intelligent DOA detection in full space and wide band. Moreover, it will provide breakthrough inspiration for traditional applications incorporating time-saving and equipment-simplified majorization.