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［Objective］ During the operation of superconducting maglev trains, factors such as inconsistencies in ground coil alignment and large electromagnetic air gaps often generate significant high-order higher harmonics in the magnetic field. These harmonics considerably affect the suspension performance of the train. It is essential to study the electromagnetic characteristics and the distribution of superconducting and suspension magnetic fields under high-speed operation conditions. ［Method］ Using the MLX01 train on Yamanashi Maglev Test Line as a case study, the suspension mechanism of superconducting maglev trains is introduced, and the theoretical foundations for calculating superconducting and suspension magnetic fields are explained. The magnetomotive force distribution models of coil along the train operating and suspension directions are established. The space harmonic method is used to decouple the energy conversion process of ′superconducting magnetic field—8-shaped coil induced current—suspension magnetic field′, and to analyze the proportion of high-order harmonics in the superconducting magnetic field. Based on the 8-shaped coil structure and parameters, the induced current in 8-shaped coils is calculated, and a harmonic analysis of the suspension magnetic field is performed. ［Result & Conclusion］ On the surface of 8-shaped coils, the fundamental wave and the third harmonic dominate the superconducting magnetic field magnetic flux density, with a fundamental wave amplitude of 1.113 T, and a third harmonic proportion of 19.40% of fundamental wave. In the suspension magnetic field magnetic flux density, the fundamental wave and the fifth harmonic dominate, with a fundamental wave amplitude of 0.065 T, and a fifth harmonic proportion of 46.70% of fundamental wave.

Resistance to apoptosis in esophageal squamous cell carcinoma (ESCC) constitutes a significant impediment to treatment efficacy. Exploring alternative cell death pathways and their regulatory factors beyond apoptosis is crucial for overcoming drug resistance and enhancing therapeutic outcomes in ESCC.

C19H17FINO4, triclinic, P1̄ (no. 2), a = 7.1158(2) Å, b = 11.1914(3) Å, c = 12.4974(3) Å, α = 73.015(2)°, β = 87.945(2)°, γ = 78.137(2)°, V = 931.19(4) Å3, Z = 2, R gt(F) = 0.0563, wRref (F 2) = 0.1639, T = 293(2) K.

Abstract Background Anthrax is a global health concern, with cutaneous anthrax accounting for over 95% of cases and generally promising outcomes. Nonetheless, the absence of timely intervention can result in mortality rates of 10–40%. This research aims to explore the clinical presentations and phenotypic characteristics of cutaneous anthrax patients and evaluate the efficacy of various therapeutic approaches. Methods A retrospective study was performed on 76 cutaneous anthrax patients identified at three hospitals from 2017 to 2022. Patients were categorized based on their hospital stay into two groups: those hospitalized for at least seven days and those for shorter durations. We assessed their clinical and phenotypic profiles, including symptoms, general health status, and laboratory findings, alongside treatment outcomes, focusing on corticosteroids therapy and antibiotic regimens. Results The study encompassed 76 diagnosed individuals, predominantly young adult males (78.9%). A significant gender disparity was noted. Hormonal treatment markedly improved edema regression in patients (P

ObjectiveTo investigate the levels of seven organophosphorus esters （OPEs） and six indicator polychlorinated biphenyls （PCBs） in pig liver from Hubei Province， the risk of exposure to OPEs and PCBs in Hubei residents through dietary intake of pig liver were assessed.MethodsA total of 51 pig liver samples were collected from Hubei Province in 2022. By isotope dilution method， OPEs and PCBs in pig liver samples were determined by ultra-high performance liquid chromatography tandem mass spectrometry （UPLC-MS/MS） and high resolution gas chromatography high resolution magnetic mass spectrometry （HRGC-HRMS）， respectively. The source of pollution was explored by analyzing the fingerprint characteristics. Based on the estimation dietary intake （EDI） and hazard index （HI） of Hubei residents， the risk of exposure to OPEs and PCBs through dietary intake of pig liver was assessed.ResultsThe levels of seven OPEs （∑7OPEs） in pig liver ranged from 15.6 to 262 ng/g， with an average of 89.7 ng/g （P50=88.4 ng/g）. The levels of six PCBs （∑6PCBs） ranged from 3.67 to 19.5 pg/g， with an average of 9.02 pg/g （P50=8.21 pg/g）. Tris （1，3-Dichloro-2-Propyl） Phosphate （TDCPP） and PCB 52 was the main characteristic pollutant of OPEs and PCBs in pig liver， respectively. Some OPEs were positively correlated with each other （r=0.278-0.841， P

With the rapid advancement of three-dimensional visual perception devices such as 3D scanners and LiDAR, the field of 3D model recognition is gradually gaining the attention of a growing number of researchers. This domain encompasses two core tasks: 3D model classification and retrieval. Since deep learning has already achieved significant success in two-dimensional visual tasks, its introduction into the realm of three-dimensional visual perception not only breaks free from the constraints of traditional methods but also makes notable strides in areas such as autonomous driving and intelligent robotics. However, the application of deep learning techniques to 3D model recognition tasks still faces several challenges. In light of this, there is a need for a comprehensive review of the application of deep learning in 3D model recognition. This review begins by discussing commonly used evaluation metrics and public datasets, providing relevant information and sources for each dataset. Subsequently, it delves into representative methods from various angles, including point clouds, views, voxels, and multimodal fusion. It also summarizes recent research development in the field. Through performance comparison on these datasets, the strengths and limitations of each method are analyzed. Finally, based on the merits and demerits of these approaches, the review outlines the challenges currently faced by 3D model recognition tasks and provides an outlook on future trends in this field.

Abstract [Objective] Rosa odorata is an important germplasm resource of Rosa, which has high value of appreciation and utilization. In order to promote the development and utilization of the germplasm resources, the chromosome ploidy, floral synthesis, and characteristics of breeding systems of different R. odorata were studied. [Methods] The chromosome ploidy, pollen vitality, stigma vitality, and flower characteristics of 9 R. odorata were observed and determined by flow cytometer and outcrossing analysis. We also analyzed the breeding systems. [Results] (1) 9 R. odorata were identified as diploid, and their flowers were bisexual with bright colors and mostly double or semi-double petals. Male and female flowers of 5 varieties were matured at different time. (2) 9 R. odorata pollen vitalities were low, with the highest vitality of 35.47%. The outcrossing index (OCI) of all varieties was ≥4, and pollen volume-ovule ratio (P/O) values ranged from 6 709 to 75 521. [Conclusion] The breeding system of 9 R. odorata is mainly outcrossing, and the breeding system is affected by many factors, such as the number of pollen grains and petals.

Swept-source optical coherence tomography angiography(SS-OCTA)is a new vascular imaging technique that was recently proposed. It has the advantages of being non-invasive, quick, high-resolution, and automated vascular stratification imaging. It is extremely helpful in the early diagnosis of ophthalmology-related diseases, as well as in the evaluation of treatment effectiveness and the tracking of disease progression. Based on the foundation of OCTA, SS-OCTA utilizes a fast-tuning laser with a wavelength of 1 050 nm for deeper penetration and non-invasive depth-resolved imaging of the retinal and choroidal microvascular systems, deepening the understanding of the characteristics of a wide range of ophthalmic diseases(fundus lesions, glaucoma, neurodegenerative diseases, etc.). The structures of the anterior segment of the eye can also be studied using SS-OCTA, including changes in the depth and density of corneal neovascularization as well as changes in iris neovascularization before and after therapy. This approach provides a novel tool for ophthalmic clinical practice. The development of the clinical use of SS-OCTA technology in ophthalmology is reviewed in this article.

ObjectiveTo investigate the contamination levels of indicator polychlorinated biphenyls （PCBs） in pork in China and the dietary exposure and risks of Chinese residents.MethodsThe concentration of seven indicator PCBs （PCB 28， PCB 52， PCB 101， PCB 118， PCB 138， PCB 153， and PCB 180） in 203 pork samples from 13 provinces （autonomous regions， centrally administered municipality） in China in 2020 as monitoring sites were analyzed by combined isotope dilution-gas chromatography-high resolution mass spectrometry. The health risk of the population exposure of indicator PCBs through pork was assessed in conjunction with date on pork consumption in each province.ResultsThe mean concentrations of the seven indicator PCBs （∑7PCBs） in pork ranged from 0.053 （Guangxi） to 0.826 ng/g fat （Zhejiang）， and P95 concentrations ranged from 0.091 （Guangxi） to 2.702 ng/g fat （Zhejiang）. PCB 28 and PCB 52 were the main fingerprint features. The mean and P95 levels of ∑7PCBs ingested daily by Chinese residents through pork consumption were 0.062±0.076 （ng/kg·BW） and 0.158±0.207 （ng/kg·BW）， respectively， and the exposure risk index （ERI） was less than 1.ConclusionThe contamination level of ∑7PCBs in pork in China， as well as the health risk of residents exposed to indicator PCBs through a pork diet was low.

[Objective]The flow of private data elements plays a crucial role in the food supply chain, and the safe and efficient operation of the food supply chain can be ensured through the effective management and flow of private data elements. Through collaborative computing among the whole chain of the food supply chain, the production, transportation and storage processes of food can be better monitored and managed, so that possible quality and safety problems can be detected and solved in a timely manner, and the health and rights of consumers can be safeguarded. It can also be applied to the security risk assessment and early warning of the food supply chain. By analyzing big data, potential risk factors and abnormalities can be identified, and timely measures can be taken for early warning and intervention to reduce the possibility of quality and safety risks. This study combined the industrial Internet identification and resolution system with the federated learning algorithm, which can realize collaborative learning among multiple enterprises, and each enterprise can carry out collaborative training of the model without sharing the original data, which protects the privacy and security of the data while realizing the flow of the data, and it can also make use of the data resources distributed in different segments, which can realize more comprehensive and accurate collaborative calculations, and improve the safety and credibility of the industrial Internet system's security and credibility.[Methods]To address the problem of not being able to share and participate in collaborative computation among different subjects in the grain supply chain due to the privacy of data elements, this study first analyzed and summarized the characteristics of data elements in the whole link of grain supply chain, and proposed a grain supply chain data flow and collaborative computation architecture based on the combination of the industrial Internet mark resolution technology and the idea of federated learning, which was constructed in a layered and graded model to provide a good infrastructure for the decentralized between the participants. The data identification code for the flow of food supplied chain data elements and the task identification code for collaborative calculation of food supply chain, as well as the corresponding parameter data model, information data model and evaluation data model, were designed to support the interoperability of federated learning data. A single-link horizontal federation learning model with isomorphic data characteristics of different subjects and a cross-link vertical federation learning model with heterogeneous data characteristics were constructed, and the model parameters were quickly adjusted and calculated based on logistic regression algorithm, neural network algorithm and other algorithms, and the food supply chain security risk assessment scenario was taken as the object of the research, and the research was based on the open source FATE (Federated AI Technology) federation learning model. Enabler (Federated AI Technology) federated learning platform for testing and validation, and visualization of the results to provide effective support for the security management of the grain supply chain.[Results and Discussion]Compared with the traditional single-subject assessment calculation method, the accuracy of single-session isomorphic horizontal federation learning model assessment across subjects was improved by 6.7%, and the accuracy of heterogeneous vertical federation learning model assessment across sessions and subjects was improved by 8.3%. This result showed that the single-session isomorphic horizontal federated learning model assessment across subjects could make full use of the data information of each subject by merging and training the data of different subjects in the same session, thus improving the accuracy of security risk assessment. The heterogeneous vertical federated learning model assessment of cross-session and cross-subject further promotes the application scope of collaborative computing by jointly training data from different sessions and subjects, which made the results of safety risk assessment more comprehensive and accurate. The advantage of combining federated learning and logo resolution technology was that it could conduct model training without sharing the original data, which protected data privacy and security. At the same time, it could also realize the effective use of data resources and collaborative computation, improving the efficiency and accuracy of the assessment process.[Conclusions]The feasibility and effectiveness of this study in practical applications in the grain industry were confirmed by the test validation of the open-source FATE federated learning platform. This provides reliable technical support for the digital transformation of the grain industry and the security management of the grain supply chain, and helps to improve the intelligence level and competitiveness of the whole grain industry. Therefore, this study can provide a strong technical guarantee for realizing the safe, efficient and sustainable development of the grain supply chain.

In China, bronchial asthma has emerged as the second most prevalent respiratory disease, with mild asthma constituting 50%-70% of the reported cases. The challenges in diagnosing mild asthma arise from the subtle or atypical symptoms exhibited by patients, coupled with the absence of characteristic wheezing sounds. Notably, pulmonary function tests frequently yield normal indices for large airway functions, contributing to a significant misdiagnosis rate exceeding 70%. This high misdiagnosis rate results in patients seeking medical care repeatedly， and some cases receiving inappropriate treatments, with incresed the risk of progressing to moderate or severe asthma, experiencing acute attacks, and facing the potential threat of mortalitydeath. About one-third of asthma deaths occur in mild asthma. Furthermore, the predominant focus on symptom relief rather than the effective control of airway inflammation raises significant concerns regar-ding the diagnosis and treatment of mild asthma in China. In response, the "Expert consensus on the diagnosis, treatment and management of mild bronchial asthma in China (2023 edition)" introduces two diagnostic pathways, namely definitive and presumptive diagnosis, with the aim of enhancing diagnostic accuracy and standardizing treatment approaches. Based on the limitations associated with methods for definitive diagnosis (such as a bronchodilator test's positive rate less than 10% in mild asthma patients and the low clinical implementation rate of bronchial provocation tests)， and an understanding of the pathophysiological mechanisms of small airway dysfunction, a presumptive diagnosis pathway to address these inherent shortcomings is proposed. Initially, a singular pulmonary function test is employed for presumptive diagnosis, integrating small airway function with airway inflammation indices. The model is fine-tuned based on age and gender considerations. The assessment of large and small airway reversibility in patients with negative bronchodilator tests serves as a pivotal guide for diagnostic treatment, minimizing the risks of misdiagnosis and overdiagnosis. Treatment and management strategies are selected based on the level of symptom control, with an emphasis on anti-inflammatory approaches. Employing a patient-centered shared decision-making model and implementing an "assessment-adjustment-review" asthma management cycle to individualize precision management is executed to establish diagnostic and treatment strategies for mild asthma, enhancing the overall standard of care for mild asthma.

Malnutrition is a common cancer treatment side effect, leading to the decreased treatment tolerance and increased risk of complications induced by chemotherapy and radiotherapy. This paper summarized the studies on malnutrition among patients with lung cancer in perspectives of risk factors, evaluation tools and nursing interventions, in order to provide reference for clinical practice of lung cancer treatment and nursing. (营养不良是肺癌患者常见症状。营养不良可导致患者治疗耐受性下降、放化疗不良反应风险增加, 严重影响肺癌患者生活质量。本文从肺癌患者营养不良发生的危险因素、评估工具、护理干预措施等方面进行综述, 以期为临床护理人员选择合适的评估工具、给予有效的护理干预措施提供参考依据。)

The influence of annealing at various temperatures on the phase stability and microstructure of pulsed-wave laser mode (PW) 316L stainless steel fabricated via Directed Energy Deposition (DED) was systematically investigated. The microstructural alterations resulting from heat treatment were examined to clarify their influence on the mechanical properties of the specimens subjected to tensile loading. The results showed that cell size increased with annealing temperature, with the cellular microstructure disappearing at higher temperatures (T ≥ 1000 °C). A decrease in the mechanical strength of the specimens was observed as annealing temperature increased. Additionally, the influence of different laser pulse frequencies and duty cycles on residual stresses was examined, revealing that moderate laser frequencies and duty cycles effectively reduced residual stress levels.

To address the limitations of traditional optimization methods in achieving high accuracy in high-dimensional problems, this paper introduces the snow leopard optimization (SLO) algorithm. SLO is a novel meta-heuristic approach inspired by the territorial behaviors of snow leopards. By emulating strategies such as territory delineation, neighborhood relocation, and dispute mechanisms, SLO achieves a balance between exploration and exploitation, to navigate vast and complex search spaces. The algorithm’s performance was evaluated using the CEC2017 benchmark and high-dimensional genetic data feature selection tasks, demonstrating SLO’s competitive advantage in solving high-dimensional optimization problems. In the CEC2017 experiments, SLO ranked first in the Friedman test, outperforming several well-known algorithms, including ETBBPSO, ARBBPSO, HCOA, AVOA, WOA, SSA, and HHO. The effective application of SLO in high-dimensional genetic data feature selection further highlights its adaptability and practical utility, marking significant progress in the field of high-dimensional optimization and feature selection.

As global energy demands continue to rise, the development of unconventional oil resources has become a critical priority. However, the complexity and high dimensionality of these problems often cause existing optimization methods to get trapped in local optima when designing key tools, such as deep-sea probes. To address this challenge, this study proposes a novel meta-heuristic approach—the Salmon Salar Optimization algorithm, which simulates the social structure and collective behavior of salmon to perform high-precision searches in high-dimensional spaces. The Salmon Salar Optimization algorithm demonstrated superior performance across two benchmark function sets and successfully solved the constrained optimization problem in deep-sea probe design. These results indicate that the proposed method is highly effective in meeting the optimization needs of complex engineering systems, particularly in the design optimization of deep-sea probes for unconventional oil exploration.

The Cu–15Ni–8Sn alloy ingot was prepared in the medium-frequency induction melting furnace. The hot extruded alloy was treated by solid solution at 840 °C for 60 min and aging at 400 °C for different times (0 miñ480 min). The effect of aging time on the evolution of the nanophase of Cu–15Ni–8Sn alloy and the strengthening-toughening mechanism were studied. The results show that at the beginning of aging, the alloy undergoes spinodal decomposition, the wavelength of the modulated structure is approximately 3∼7 nm, the ordered phase transformation of D022 and L12 occurs simultaneously, and the ordered phase size is approximately 5 nm. With the extension of aging time, the modulated structure became coarser, and the wavelength of the modulated structure increased to 5–9 nm. At the same time, the D022 ordered phase changed to the L12 ordered phase, and a continuous distribution of elliptical discontinuous precipitation appeared at the grain boundary. The ratio of the long and short axes of the discontinuous precipitation was approximately 4.7. In the late aging period, the D022 ordered phase was basically transformed into the L12 ordered phase, and discontinuous precipitation, which is incompatible with the matrix, extended into the crystal. After 120 min of aging at 400 °C, the hardness, strength, and elongation of the alloy are 105.4 HRB, 839.8 MPa and 9.6 %, respectively. The peak-aging states D022 and L12 coexist in an orderly phase at the nanoscale, and this nanoscale strengthening phase is completely integrated with the matrix, which improves the strength and toughness of the alloy. The research results can provide support for the development of high-performance copper alloys in the ocean.

Obtaining the real-time fatigue crack length of a metallic structure is the prerequisite of the fatigue life monitoring and residual life estimation for an aircraft. This paper proposed a metallic structure's fatigue crack prediction model using strain monitoring data based on deep learning method. A cycle consistent adversarial network was developed to map the strain monitoring data from experimental measurement with those from finite element modeling. A crack size classification model and a crack length quantification model were proposed to classify the crack size range and identify the exact crack length, respectively. The proposed model was applied to predict the fatigue crack growth in centeral hole metallic plates subjected to random loading spectrum. The results showed that the prediction is effective and accurate.

Objective: To explore a green and efficient method for extracting chitin. Methods: The crayfish shells were crushed through three mesh sieves to obtain the raw material. Utilizing ultrasonic wave and citric acid and urea to remove calcium and protein from the sample, decolorize it with hydrogen peroxide, filter it, and then dry it to produce chitin products. The particle size of the chitin sample was analyzed by laser scattering particle size distribution analyzer. Infrared absorption characteristics were measured by an infrared spectrometer. Scanning electron microscopy was used to observe the apparent structure of the sample. Results: It was shown that the larger the mesh size, the higher the purity of the chitin product. The yield of chitin from 200 mesh crayfish shell powder increased to 43.93%, and the purity increased to 55.39%. The particle size of chitin samples obtained from shrimp shell powder of three mesh numbers after plasma treatment decreased from 340.05, 184.30, and 137.39 μm without plasma treatment to 195.95, 159.02, and 53.51 μm respectively. Infrared spectrum analysis showed that the crayfish shell powder treated by plasma-assisted ultrasonic-assisted weak acid and weak base method displayed the absorption characteristics of chitin and magenta, indicating that the main component of the treated sample was chitin. The scanning electron microscope results showed that the structure of the chitin sample was looser and the surface was uneven after plasma treatment. Multiple statistical analyses showed that screening and plasma treatment had a significant impact on the whole properties of chitin samples. Conclusion: In this study, plasma and ultrasonic-assisted weak acid and weak base extraction of chitin from crayfish shells can improve the traditional acid-base process, reduce the environmental pollution of acid-base reagents, and effectively improve the extraction rate and purity of chitin.

Significant wave height (SWH) prediction is crucial for marine safety and navigation. A slow failure particle swarm optimization for long short-term memory (SFPSO-LSTM) is proposed to enhance SWH prediction accuracy. This study utilizes data from four locations within the EAR5 dataset, covering 1 January to 31 May 2023, including variables like wind components, dewpoint temperature, sea level pressure, and sea surface temperature. These variables predict SWH at 1-h, 3-h, 6-h, and 12-h intervals. SFPSO optimizes the LSTM training process. Evaluated with R2, MAE, RMSE, and MAPE, SFPSO-LSTM outperformed the control group in 13 out of 16 experiments. Specifically, the model achieved an optimal RMSE of 0.059, a reduction of 0.009, an R2 increase to 0.991, an MAE of 0.045, and an MAPE of 0.032. Our results demonstrate that SFPSO-LSTM provides reliable and accurate SWH predictions, underscoring its potential for practical applications in marine and atmospheric sciences.

ObjectiveTo perform visual analysis of the literature in the field of adolescent social isolation in order to provide reference for research on social isolation of Chinese teenagers.MethodsLiterature related to adolescent social isolation was retrieved from the Web of Science core collection database from September 2013 to September 2022. CiteSpace 6.1.R3 software was used to conduct bibliometric analysis on publication volume， publication organization， keyword clustering， keyword salience， and time⁃line map of hot words.ResultsA total of 1 347 related articles were screened out， and the overall number of publications from 2013 showed an upward trend. The largest number of articles came from the United States with 521 （38.68%）， and China ranked 6th with 79 （5.86%）. The top three institutions were Columbia University in the United States （29 articles）， King's College London in the United Kingdom （28 articles） and the University of London in the United Kingdom （27 articles）. Research hotspots mainly focused on social isolation， physical and mental health， loneliness， quality of life and comprehensive interventions.ConclusionIn recent years， the problem of adolescent social isolation has attracted continuous attention from foreign scholars. Based on our national conditions， we should conduct relevant screening and preventive assessment for social isolation of special youth groups， so as to conduct early management and intervention.

Objective To explore from the perspective of microorganisms the changes in plaque microbial community of children with severe early childhood caries (S-ECC) before and 3 months after dental treatment. Meanwhile to show the effect of treatment on the maintenance of long- term caries-free state. Methods S-ECC children completed dental treatment under general anesthesia. We collected plaque from caries-free dental surfaces before treatment (caries, C) and at the postoperative follow-up review time points of 7 days (C-7D), 1 month (C-1 M), and 3 months (C-3 M). We included caries-free children (caries free, CF) as the control group to analyze the dynamic modification process of the plaque microbial community in the short-term pre- and postdental treatment. Results Species clustering analysis showed that the compositions of the microbial communities of the S-ECC and CF groups were highly similar. The α diversity index was not statistically significant (P>0.05). From the analysis of the relative abundance, Leptotrichia spp. and Aggregatibacter spp. decreased after treatment compared with before treatment (P

Radiation-related teeth damage is a common complication in nasopharyngeal carcinoma (NPC) patients undergoing radiotherapy (RT) that seriously affects their oral health-related quality of life (OHRQoL). However, few studies have focused on protecting teeth function. This study aimed to calculate dental dose limits based on OHRQoL. Analysis was performed on 96 NPC patients who received RT (all received routine pre-radiotherapy dental interventions in our department). Based on the General Oral Health Assessment Index (GOHAI), OHRQoL was assigned into poor (

Objective To investigate the effect of quality control circle (QCC)activity on standard prevention of venous thromboembolism (VTE)among hospitalized pregnant women. Methods Totally 88 hospitalized pregnant women were recruited in this study, in which 44 cases were hospitalized before implementation of QCC activity and another 44 cases were hospitalized after implementation of QCC activity. The rate of standard VTE prevention, VTE awareness, compliance rate of function exercise, rate of sufficient daily intake of water and satisfaction with nursing service were measures before and after implementation of QCC activity. Results The rate of standard VTE prevention increased from 54. 55%(24/44)before implementation of QCC activity to 81. 82%(36/44)after implementation of QCC activity. Higher score of VTE knowledge assessment, rate of function exercise and sufficient daily intake of water were observed after implementation of QCC activity compared with those before implementation of QCC activity(P＜0. 01). Nursing satisfaction rate was increased significantly after implementation of QCC activity(P＜0. 05). Conclusion The QCC activity is potentially effective to improve hospitalized pregnant women’s awareness and behavior of standard VTE prevention, therefore reducing the risk of VTE during pregnancy. (目的 探讨品管圈活动在提高住院孕产妇静脉血栓栓塞(VTE)规范预防率中的应用效果。方法 选取 2021年1月—6月妇产科收治的88位孕产妇为研究对象, 其中实施品管圈活动前收治44例, 活动开展后收治44例。比较活动前和活动后孕产妇VTE规范预防率、VTE相关知识掌握情况、功能锻炼执行率、每日充足饮水达标率及护理满意度。结果 住院孕产妇VTE规范预防率由活动前的54. 55%(24/44)提高至活动后的81. 82%(36/44)。品管圈活动后, 孕产妇VTE知识掌握情况、功能锻炼执行率、每日充足饮水达标率均高于活动前(P＜0. 01); 住院孕产妇对护理满意度高于活动前(P＜0. 05)。结论 对住院孕产妇开展品管圈活动, 可提升其对VTE相关知识的认知程度, 提高VTE规范预防率, 对降低VTE 发生风险具有积极意义。)

Cancer poses a serious threat to human health and is the most common cause of human death. Polymer-based nanomedicines are presently used to enhance the treatment effectiveness and decrease the systemic toxicity of chemotherapeutic agents. However, the disadvantage of currently polymeric carriers is without therapy procedure. Herein, for the first time, glutathione (GSH)-responsive polymer (PRES) with anti-cancer effect was synthesized following the condensation–polymerization method using resveratrol (RES) and 3,3′-dithiodipropionic acid. PRES can not only suppress the tumor cells growth but can also self-assemble into nanoparticles (∼93 nm) for delivering antitumor drugs, such as paclitaxel (PTX@PRES NPs). The system could achieve high drug loading (∼7%) and overcome multidrug resistance (MDR). The results from the in vitro studies revealed that the NPs formed of PRES were stable in the systemic circulation, while could be efficiently degraded in tumor cells high GSH environment. Results from cytotoxicity tests confirmed that PTX@PRES NPs could effectively suppress the growth of cancer cells (A549) and drug-resistant cells (A549/PTX). The NPs could also be used to significantly increase the therapeutic efficacy of the drugs in A549/PTX tumor-bearing mice. In vivo investigations also demonstrated that the PRES-based NPs exhibited tumor inhibition effects. In summary, we report that the GSH-responsive polymer synthesized by us exhibited multiple interesting functions and could be used for effective drug delivery. The polymer exhibited good therapeutic effects and could be used to overcome MDR. Thus, the synthesized system can be used to develop a new strategy for treating cancer.

3D object detection is a new research direction in recent years, and its main task is the location and recognization of targets in space. The existing methods for 3D object detection using monocular or binocular stereo vision are easily affected by object occlusion, viewpoint changing and scale changing in 3D scene, there will be problems such as poor detection accuracy and robustness. LiDAR point cloud can provide 3D scene information, so using deep learning method to complete 3D object detection based on LiDAR point cloud has become a research hotspot in the field of 3D vision. Aiming at the 3D object detection based on LiDAR point cloud, the relevant research in recent years is reviewed. Firstly, the 3D object detection methods based on LiDAR point cloud are divided into point cloud based, point cloud projection based, point cloud voxelization based and multi-modal fusion based 3D object detection methods according to the data form of network input, and the most representative methods in each category are described in detail. Then common datasets are introduced, and the performance of representative methods is evaluated, and the advantages and limitations of each method are discussed from several aspects. Finally, the shortcomings and difficulties are given, and the future development directions are also discussed and put forward.

Nowadays, the vehicle detection technology based on lidar has been widely used in the field of intelligent connected vehicles. Accurate vehicle detection and shape estimation can provide accurate static information for follow-up tracking and prediction. Although the existing vehicle detection algorithm based on lidar can accurately detect and classify each target vehicle, there is a problem of unstable estimation when the vehicle point cloud contour is partially obscured in an "L" shape. In order to solve this problem, this paper proposes a vehicle shape optimization algorithm based on point cloud cluster features, the proposed algorithm outputs vehicle detection results with PointPillars target detection algorithm. Vehicle shape refinement module based on point cloud cluster features is adopted to further estimate the shape and heading of vehicle detection results. The experimental results in multiple scenes show that the vehicle shape refinement algorithm proposed in this paper can effectively improve the stability of vehicle shape and heading estimation to a certain extent compared with the existing vehicle detection algorithms, and the average consuming-time per frame of all algorithm module is 88.93 ms, which can meet the real-time requirement of vehicles.

Internet gaming disorder (IGD) has a great negative impact on teenagers’ study and life. It has been included in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders in 2013. However, the neural mechanism of its effect is yet to be unveiled. In this study, we used resting-state functional magnetic resonance imaging (resting-state fMRI) to explore the differences of rich club structures in the functional brain networks of 30 IGD subjects and 30 age/sex-matched healthy controls. The rich club was found in both IGD subjects and healthy controls, involving important brain regions in default mode, executive control, salience, sensorimotor, auditory and visual networks. IGD subjects had significantly higher rich club connection and higher degree in the right pars orbitalis of inferior frontal gyrus than healthy controls. These findings might suggest that IGD might be more correlated with damage to the rich club connection.

Additive manufacturing technology as revolutionary manufacturing technology has attracted much attention.This technology transformed traditional processing design and manufacturing concepts and promoted the development of intelligent manufacturing. Intelligent material is a kind of material that has the ability of self-perception, autonomous response, self-healing and adaptation. The combination of intelligent materials and additive manufacturing technology can realize the integrated manufacturing of three-dimensional smart devices with the ability to sense external stimuli or environmental activation. This technology has been widely used in fields such as biomedical devices, flexible electronics, soft robotics, and other fields.Additive manufactured intelligent materials, and the advantages and problems of additive manufactured intelligent materials of metals, polymers, and ceramics were reviewed.As a technical means to realize the organic integration of design, material and structure, additive manufacturing technology will become the key to promote the development of intelligent materials.

ObjectiveTo measure perfluoroalkyl and polyfluoroalkyl substances （PFASs） in cord blood of newborns in Henan province and explore influencing factors of PFASs exposure.MethodsThe present study was based on the birth cohort established in Henan Province from 2013 to 2015. The levels of 11 PFASs in cord blood samples （n＝336） were detected. Generalized linear regression was used to analyze the effects of maternal socio­demographic characteristics， life style and dietary intake on the level of PFASs in umbilical blood of newborns.ResultsThe newborns of older mothers （GM ratio 1.03-1.05）， higher average monthly family income （GM ratio 1.30-1.63）， pregnancy smoking （GM ratio 2.90， 95% CI：1.11， 7.56） and passive smoking （GM ratio 1.84， 95%CI： 1.02， 3.32） tend to show higher PFAS exposure in cord blood. Newborns whose mothers worked during pregnancy （GM ratio 0.82， 95%CI：0.67，1.00）， and with multiparous mothers （GM ratio 0.65， 95% CI： 0.51， 0.82） had lower concentrations of PFASs. Mothers who had higher intake frequency of beef or mutton， pumpkin， garlic seedlings and pickles during pregnancy tend to have increased concentrations of PFASs in cord blood （GM ratio was 1.33-1.80）， while the concentration was lower during mothers who consumed more oranges， milk， cabbage and eggplant during pregnancy （GM ratio was 0.68-0.82）.ConclusionMaternal age， family income， history of smoke and passively smoke during pregnancy， parity， frequency of beef or mutton， and plant­based foods intake may affect PFASs exposure of newborns.

Laboratory animal disease models play an important role in clinical translational research, and have been widely used in life sciences, medical chemistry, and biological health. In addition, animal models are often used as effective tools to study cancer occurrence, development, and metastasis. In recent years, with the increasing demand for precision medicine, the patient-derived tumor xenograft (PDX) model has been widely used as an important model for drug screening and translational research in the development of anti-cancer drugs and the introduction of personalized treatment plans for individuals. With the perspective of the development of experimental animal tumor models and the application of immunodeficient animals, this review summarizes the status of PDX models in precision medicine, defines the characteristics of different types of animal models, and provides prospects for future development trends and applications.

The requirement of high power rated, efficient and high power density grid connected converters has increased due to their extended use in multiple applications such as battery chargers. The proliferation of electric vehicles (EVs) in the transportation market is essentially associated with the performance and reliability of battery chargers. An efficient, compact and fast battery charger is indispensable in order to provide a way to charge an EV in a short time. In view of this fact, this article proposes a soft-switching three-level T-type vienna rectifier, which can be used as a front-end power stage converter in an on-board EV battery charger. The proposed topology achieves high efficiency and high power density by employing soft-switching strategy, which is achieved by incorporating a simple auxiliary network in the proposed circuit. The reduced component stresses and simple control strategy make it an appealing candidate for EV industries to develop this front-end PFC rectifier as a fast battery charger. The high switching operation with reduced power losses, regulated DC at the output, low-harmonic grid current and power factor correction operation are achieved with the proposed topology. The construction, operating principle and simulation analysis of the proposed converter are discussed in detail. In order to show the stand-point of the proposed scheme, a fair comparison of the proposed soft-switched converter with an existing soft-switched 3-level neutral-point diode-clamped converter is carried out in terms of the number of components and complexity in the PWM signals generation. Additionally, an efficiency comparison of the suggested converter is carried out with some existing well-known rectifier topologies at different power loads. The practical implementation of the proposed power converter scheme is checked by building a laboratory-prototype to perform an experimental analysis.

The heterogeneous trans-scale structures play important roles in achieving high strength and toughness in austenitic stainless steels fabricated by directed energy deposition (DED). In this study, systematic annealing investigations were demonstrated the evolution of trans-scale heterogeneous structures such as dislocations, chemical cells, nano-oxides, grains and recrystallization behavior. Their effects on yield strength were quantified. The experimentally observed yield strength of as-received and annealed samples agrees well with the estimated yield strength using standard Taylor hardening formulae. The dislocation intensity accounted for 200 MPa and became the main strength contributor, among which GND type of dislocation accounted for more than 60% of the total dislocation. Despite the development of DED steel micro inclusions, the synergistic effect of deformation twinning and pre-existing GND-induced back stress results in high tensile plasticity. This research helps to better understand the interplay between DED processing, the microstructure of 316L stainless steel and the mechanical properties that are crucial to meeting new demands.

ObjectiveTo prepare reference materials of dioxins and dioxin-like polychlorinated biphenyls in fish powder matrix.MethodsUsing fly ash to feed grass carp, the fish samples were peeled, homogenized, dried, packed and sterilized. After homogeneity and stability studies, coordinated values were determined by 8 laboratories, and the uncertainty was evaluated.ResultsThe reference material had good uniformity and the stability was more than 12 months. The characteristic values of PCDD/Fs were 0.017-1.4 pg/g, the expanded uncertainty were 0.02-0.6 pg/g and the characteristic values of DL-PCBs were 0.54-16 pg/g, expanded uncertainty were 0.28-6 pg/g. The matrix reference material was approved by the evaluation committee(GBW(E)100741).ConclusionThe matrix reference material has good homogeneity and stability, which can be used in the quality control for analyzing, laboratory ability verification, analytical instrument calibration, analysis method accuracy evaluation and verification, etc.

Objective: This study aimed to establish a method for quick determination of 3 kinds ofmethylimidazole compounds in food flavor. Methods: The food flavor was extracted with 5% trichloroacetic acid solution and purified with PCX mixed cationic solid phase extraction column. Finally, the qualitative and quantitative analysis was carried out by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) and internal standard method. Results: The linear relationship between the three methyl imidazole compounds was good in the range of 5.0~400.0 ng/mL, with correlation coefficient R2≥0.997. The limits of detection were 0.030~0.450 μg/kg and the limits of quantification (LOQ) were 0.10~1.50 μg/kg. The recoveries of three methylimidazole ranged from 82.8% to 111.7%, and the relative standard deviations (RSDS) ranged from 1.3% to 9.3%. Conclusion: The method is simple, efficient and accurate, and can be used for the quantitative determination of 1-methylimidazole, 2-methylimidazole, 4-methylimidazole in food flavor.

Objective To investigate the changes in the sagittal diameter of the upper airway before and after the treatment of skeletal Class Ⅲ malocclusion in adults with microimplant anchorage and class Ⅲ intermaxillary elastics and to provide a reference for clinical treatment. Methods A total of 35 adult patients with skeletal Class Ⅲ malocclusion were selected to be treated with the straight-wire technique. Microimplant group, 15 cases (group A): patients with severe skeletal Class Ⅲ malocclusion (vertical high angle) were treated with the straight-wire technique combined with microimplant anchorage; class Ⅲ intermaxillary elastics group, 20 cases (group B): Patients with mild or moderate skeletal Class Ⅲ malocclusion (vertical low angle and average angle) were treated with the straight-wire technique combined with class Ⅲ intermaxillary elastics, and cephalometric radiographs obtained before and after treatment in the upper airway in the two groups were measured and analyzed. Results Changes in cranial and maxillofacial measurements after correction: in group A, (sella-nasion-supramental angle) the SNB angle decreased significantly (P < 0.05), and (subspinale-nasion-supramental angle) the ANB angle increased significantly (P < 0.05). In group B, the SNB angle decreased significantly (P < 0.05), while (subspinale-nasion-subspinale angle) the SNA angle、ANB angle and anterior skull base plane-mandibular plane angle (Sn-MP) angle increased significantly (P < 0.05). Changes in sagittal diameter of the upper airway measurements after corrections: In group A, the width of the glossopharyngeal segment of the upper airway (TB-TPPW) decreased significantly (P < 0.05). In group B, first segment width of the upper airway behind the hard palate (PNS-R) increased significantly (P < 0.05). After correction, the decreased SNB and increased ANB in group A was higher than that in group B, and the difference was statistically significant （P < 0.05）. The decreased of TB-TPPW in upper airway of group A was greater than that of group B, and the difference was statistically significant （P < 0.05）. Conclusions In the treatment of skeletal class Ⅲ malocclusion with microimplant anchorage, the sagittal diameter of the glossopharyngeal segment of the upper airway has a negative impact.

In recent years, as a hot spot in the field of computer vision, human pose estimation has broad application prospects in video surveillance, human-computer interaction, and intelligent campus. With the rapid development of neural networks, the use of deep learning methods for 2D human pose estimation, compared with traditional methods that require manual setting of features, can more fully extract image information, and obtain more robust characteristics, so deep learning based methods have become the mainstream of 2D human pose estimation algorithm research. However, deep learning is still developing, there are still problems such as large training scale, and researchers mainly start with designing networks and training methods to improve the human pose estimation algorithm. Fristly, the two-dimensional human pose estimation is divided into two categories: single person and multiple persons. Secondly, single-person pose estimation is divided into coordinate regression and heat map detection according to different ground truth types, and multi-person pose estimation is divided into two-step and single-step method according to different algorithm steps, to summarize and classify the advanced algorithms in recent years, and their advantages and disadvantages as well as scope of application are analyzed. Then, the international standard datasets and the corresponding evaluation indices are introduced, and some classical algorithms are compared experimentally. Finally, the current research problems and the future development trends are summarized.

We investigate the photovoltaic behaviors of magnetic graphene interconnect junctions, which are constructed by zigzag graphene nanoribbons (ZGNRs), with the aim to produce pure spin current by photogalvanic effect (PGE). Two kinds of interconnect junctions are designed by connecting two 6-ZGNR with a carbon hexagon (C6) and a carbon tetragon (C4), respectively. It is found that zero charge current is produced under irradiation of light in both structures due to the presence of spatial inversion symmetry. Nevertheless, behind the zero charge current, net pure spin current is produced in the structure with a C6, but not in the structure with a C4. This difference originates from their different edge state distribution and different spatial inversion symmetry of the spin density. However, interestingly, local edge pure spin current can be obtained in both structures. More importantly, the pure spin current generation is independent of the photon energy, polarization type or polarization angle, suggesting a robust way of generating pure spin current with PGE and new possibility of graphene’s applications in spintronics.

BackgroundApproximately 1.1 million people living with HIV live in the United States, and the incidence is highest in Southeastern United States. Electronic patient portal prevalence is increasing and can improve engagement in primary medical care. Retention in care and viral suppression—measures of engagement in HIV care—are associated with decreased HIV transmission, morbidity, and mortality. ObjectiveWe aimed to determine if patient portal access among people living with HIV was associated with retention and viral suppression. MethodsWe conducted an observational cohort study among people living with HIV in care at the Vanderbilt Comprehensive Care Clinic (Nashville, Tennessee) from 2011-2016. Individual access was defined as patient portal account registration at any point in the year prior. Retention was defined as ≥2 kept appointments or HIV lab measurements ≥3 months apart within a 12-month period. Viral suppression was defined as the last viral load in the calendar year