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EMD empowered neural network for predicting spatio-temporal non-stationary channel in UAV communications

APPLIED INTELLIGENCE 2025年第4期55卷 1-28页

作者： Zhang, Qiuyun Guo, Qiumei Jiang, Hong Yin, Xinfan Mushtaq, Muhammad Umer Luo, Ying Wu, Chun Southwest Univ Sci & Technol Sch Informat Engn 59 Qinglong Rd Mianyang 621010 Sichuan Peoples R China Natl Univ Def Technol Coll Intelligence Sci & Technol 137 Yanwachi St Changsha 410073 Hunan Province Peoples R China Univ Pretoria Dept Comp Sci Cnr Lynnwood Rd & Roper St Hatfield ZA-0082 Pretoria Gauteng South Africa

This paper introduces a novel prediction method for spatio-temporal non-stationary channels between unmanned aerial vehicles (UAVs) and ground control vehicles, essential for the fast and accurate acquisition of channel state information (CSI) to support UAV applications in ultra-reliable and low-latency communication (URLLC). Specifically, an empirical mode decomposition (EMD)-empowered spatio-temporal attention neural network is proposed, referred to as EMD-STANN. The STANN sub-module within EMD-STANN is designed to capture the spatial correlation and temporal dependence of CSI. Furthermore, the EMD component is employed to handle the non-stationary and nonlinear dynamic characteristics of the UAV-to-ground control vehicle (U2V) channel, thereby enhancing the feature extraction and refinement capabilities of the STANN and improving the accuracy of CSI prediction. Additionally, we conducted a validation of the proposed EMD-STANN model across multiple datasets. The results indicated that EMD-STANN is capable of effectively adapting to diverse channel conditions and accurately predicting channel states. Compared to existing methods, EMD-STANN exhibited superior predictive performance, as indicated by its reduced root mean square error (RMSE) and mean absolute error (MAE) metrics. Specifically, EMD-STANN achieved a reduction of 24.66% in RMSE and 25.46% in MAE compared to the reference method under our simulation conditions. This improvement in prediction accuracy provides a solid foundation for the implementation of URLLC applications.

关键词： Neural network EMD Channel prediction UAV Non-stationary

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Composite aramid aerogels with anisotropic layered structure reinforced by tetra-needle-like ZnO whiskers for acoustic and thermal insulations

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JOURNAL OF MATERIALS science 2025年第5期60卷 2344-2362页

作者： Yan, Ran Qin, Wenfeng Gong, Guochong Chen, Wang Peng, Hao Zhong, Rulin Mou, Chenyu Huang, Chuanyong Zhou, Bin Civil Aviat Flight Univ China Aviat Engn Inst Guanghan Peoples R China

High-performance and multifunctional aerogels are a new generation of materials that meet modern needs in areas such as thermal and acoustic insulation, but creating the aerogels with a combination of excellent acoustic performance, good thermal conductivity, and mechanical properties is a great challenge, as these properties often have conflicting structural requirements. In this work, T-ZnOw/ANFs composite emulsion containing a large number of air bubbles is prepared by using aramid fibers as the base material, inspired by the microfoam molding process and through the addition of tetra-needle-like ZnO whiskers (T-ZnOw) with a special three-dimensional tetra-needle structure, and the composite emulsion is rapidly frozen in liquid nitrogen to prepare composite aerogels (T-ANFs) with a well-arranged, layered structure inside. The T-ANFs prepared by this process have excellent performance, and its special internal structure enables it to maintain low density and high porosity while possessing robust mechanical properties (compressive stress of 169.9 kPa at 80% strain), excellent multidimensional acoustic performance (NRC of 0.44), and low thermal conductivity (thermal conductivity down to 0.03 W (m & lowast;K)-1). Overall, the T-ANFs prepared in this work have great potential for practical applications and possess a wide range of application prospects.

关键词： Thermal conductivity

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A Comparative Prospective Study on the Accuracy and Efficiency of Autonomous Robotic System Versus Dynamic Navigation System in Dental Implant Placement

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JOURNAL OF CLINICAL PERIODONTOLOGY 2025年第2期52卷 280-288页

作者： Yu, Muqiao Luo, Yilin Li, Bolin Xu, Lingqiao Yang, Xingmei Man, Yi Sichuan Univ West China Hosp Stomatol State Key Lab Oral Dis Chengdu Sichuan Peoples R China Sichuan Univ Natl Ctr Stomatol Chengdu Sichuan Peoples R China Sichuan Univ Natl Clin Res Ctr Oral Dis Chengdu Sichuan Peoples R China Sichuan Univ West China Hosp Stomatol Dept Oral Implantol Chengdu Sichuan Peoples R China

Aim: This study aimed to evaluate the efficiency of and discrepancies between planned and final implant positions using dynamic computer-assisted implant surgery (d-CAIS) and autonomous robotic computer-assisted implant surgery (r-CAIS) in clinical practice. Materials and Methods: The study included 83 patients, who received 135 implants between December 2022 and March 2024 (r-CAIS group: 43 patients with 71 implants;d-CAIS group: 40 patients with 64 implants). Cone-beam computed tomography scans taken before and after surgery assessed linear and angular deviations between the groups in both 2D and 3D spaces. The duration of surgery was also analysed. Results: The angular deviation between d-CAIS and r-CAIS was 3.61 degrees +/- 1.65 degrees versus 1.62 degrees +/- 0.93 degrees (p < 0.001), the platform deviation was 1.12 +/- 0.51 mm versus 0.50 +/- 0.19 mm (p < 0.001) and the apex deviation was 1.36 +/- 0.57 mm versus 0.58 +/- 0.21 mm (p < 0.001). The d-CAIS group experienced significantly longer drilling and implant placement times compared to the r-CAIS group (10.6 +/- 3.8 vs. 8.3 +/- 3.4 min, p < 0.01), while preparation time showed no statistical difference between the groups (7.2 +/- 3.3 vs. 6.2 +/- 2.7 min, p > 0.05). Conclusions: The robotic system demonstrated higher accuracy and efficiency of implant placement than the dynamic navigation system in partially edentulous patients.

关键词： dental implant dynamic navigation system robotic system surgery efficiency

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Land Use Conflicts Identification and Multi-Scenario Simulation in Mountain Cities, Southwest China: A Coupled Structural and Functional Perspective

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LAND DEGRADATION & DEVELOPMENT 2025年第5期36卷 1492-1512页

作者： Li, Weijie Kang, Jinwen Wang, Yong China West Normal Univ Sch Geog Sci Nanchong Peoples R China China West Normal Univ Sichuan Prov Engn Lab Monitoring & Control Soil Er Nanchong Peoples R China Southwest Univ Sch Geog Sci Chongqing Key Lab Karst Environm Chongqing Peoples R China

Land use conflicts (LUCs) arise during land use change, causing an uncoordinated spatial structure of the land and negatively affecting the synergistic development of multifunctionality, especially in mountain cities. Previous studies have focused on identifying and measuring land use structural conflicts (LUSC), with less attention paid to land use functional conflicts (LUFC), and a lack of simulation for future multi-scenarios. Thus, taking Chongqing as an example, based on the perspective of LUSC-LUFC coupling, this study constructed a comprehensive conflict index to identify and assess LUCs, then applied the PLUS model to predict LUCs under three development scenarios in 2030. This study found that (1) there was a significant positive spatial association between LUSC and LUFC, with high-high agglomeration types in areas of severe LUCs and low-low agglomeration types in areas of light LUCs. (2) During 2000-2020, the LUCs in Chongqing displayed a trend of upward and then downward from 2000 to 2020, with significant agglomeration in their spatial pattern. (3) Two typical areas of LUCs intensification were identified, namely the topographic transition zone located in the Daba and Wuling mountains and the urban-rural interface in the Chongqing metropolitan area. (4) In 2030, the LUCs in Chongqing manifest an overall mitigation in the ecological protection (EP) scenario, while displaying an intensification in the natural development (ND) and economic development (ED) scenarios. Based on the types of spatial interaction between LUSC and LUFC, land use optimization strategies were formulated. The findings will provide scientific references for sustainable land use management decisions in Chongqing and other mountainous cities.

关键词： Chongqing land use conflicts land use functional conflict land use structural conflict scenario simulation

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Dynamic response of rock landslides and avalanche debris flows impacting flexible barriers based on shaking table tests

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SOIL DYNAMICS AND EARTHQUAKE ENGINEERING 2025年 188卷

作者： Fan, Jie Yang, Changwei Yue, Mao Luo, Jia Lian, Jing Wei, Peiyong Southwest Jiaotong Univ Sch Civil Engn Chengdu 610031 Peoples R China Xihua Univ Sch Architecture & Civil Engn Chengdu 610039 Peoples R China China Acad Railway Sci Corp Ltd Railway Engn Res Inst Beijing 100081 Peoples R China

Flexible barrier structures are commonly installed in mountainous regions to resist the impact effects of rock avalanches. Without reliable physical data, the study of rock landslide initiation and the impact mechanism of avalanche debris flow under seismic excitation remains poorly understood. In this study, a model of rock slopeflexible barrier system was developed to simulate seismic slope failure behavior and debris flow impact on flexible barriers. Seismic waves in shaking table tests were triaxially loaded to effectively simulate actual seismic responses. The results indicate that the response of the Acceleration Amplification Factor (AAF) is closely associated with seismic damage and deformation within the overlying rock layers and differential propagation of seismic energy on either side of the shear band triggers rockslide initiation. Furthermore, the progressive failure mode of modeled slopes under multiple seismic events is slip-compression cracking failure. Crushing spreading at the intersection of the cracking and slip surfaces is the source of the loose fractured rock mass. Finally, this paper examines the impact patterns and dynamic responses of large individual blocks and loose fractured deposits on flexible barriers. Large blocks cause localized strong acceleration in the steel wire nets, increasing the risk of local damage, whereas loose deposits tend to induce overall seismic deformation and instability of the supporting structure. The natural seismic damage mechanisms of the barrier structure are revealed. It is recommended that flexible barrier structures in earthquake-prone mountainous areas incorporate a reasonable footing design to ensure the columns can deflect out-of-plane in response to seismic activity.

关键词： Flexible barrier Shaking table tests Rock landslides Debris flows Seismic damage

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Association between interpregnancy interval and adverse perinatal outcomes according to maternal age in the context of China's two-child policy

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BMC PREGNANCY AND CHILDBIRTH 2025年第1期25卷 1-15页

作者： Xiu, Siqin Tang, Li Qin, Chengjie Tian, Di Chen, Yuhong Gu, Lingling Yang, Liu Sun, Yuhao Liu, Xinghui Lin, Yonghong Wang, Yumei Univ Elect Sci & Technol China Chengdu Womens & Childrens Cent Hosp Sch Med Dept Gynecol & Obstet Chengdu Peoples R China Univ Elect Sci & Technol China Chengdu Womens & Childrens Cent Hosp Sch Med Dept Hlth Care Chengdu Peoples R China Tongji Univ Shanghai East Hosp Sch Med Dept Gastroenterol Shanghai Peoples R China Sichuan Univ West China Univ Hosp 2 Dept Obstet & Gynecol Chengdu Peoples R China

Background Since the implementation of China's comprehensive two-child policy, the prevalence of long interpregnancy intervals (IPI) and advanced maternal age has increased. However, previous studies in China have mostly focused on the relationship between short IPIs and adverse perinatal outcomes, while neglecting maternal age as a potential confounder. Methods We conducted a retrospective cohort study of 23,899 pregnant women who delivered between January 1, 2017 and December 31, 2019 at Chengdu Women's and Children's Central Hospital and West China Second Hospital of sichuan University. IPIs were categorized as < 18 months, 18-23 months, 24-59 months, 60-119 months, and >= 120 months. Their relationships with clinical characteristics and pregnancy outcomes were analyzed using chi-square tests and Cochran-Armitage test for trend. Logistic regression modeling, incorporating restricted cubic spline (RCS), was used to assess association between IPI and adverse perinatal outcomes, including full-term low birthweight (LBW), preterm birth (PTB), small-for-gestational age (SGA) and adverse neonatal composite (very low birthweight, very preterm birth, severe neonatal asphyxia or death). Results Women with longer IPIs (>= 120 months) were more likely to be older (>= 35 years) and had higher rates of gestational diabetes and hypertensive disorders of pregnancy (p < 0.05). Compared to an IPI of 24-59 months, the risk of PTB was significantly higher with an IPI of >= 120 months for women aged >= 35 years (aOR,1.17;95% CI, 0.89-1.55) and 30-34 years (aOR 2.17;95% CI, 1.59-2.92), but not for those aged <= 29 years (aOR 1.34;95% CI, 0.20-5.31). The risk of SGA increased with an IPI of >= 120 months for women aged 30-34 years (aOR, 2.19;95% CI, 0.97-4.53) and with an IPI of 60-119 months for women aged <= 29 years (aOR,3.16;95% CI, 1.62-6.30). Full-term LBW risk was elevated among women aged <= 29 years with an IPI of >= 120 months (aOR, 10.42;95% CI, 0.55-59.52). However, there

关键词： Interpregnancy interval Adverse pregnancy outcomes Maternal age Small for gestational age Low birth weight Preterm birth Composite index

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Research on Defect Detection in Lightweight Photovoltaic Cells Using YOLOv8-FSD

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SENSORS 2025年第3期25卷 843-843页

作者： Chen, Chao Chen, Zhuo Li, Hao Wang, Yawen Lei, Guangzhou Wu, Lingling Sichuan Univ Sci & Engn Sch Comp Sci & Engn Zigong 643000 Peoples R China

Given the high computational complexity and poor real-time performance of current photovoltaic cell surface defect detection methods, this study proposes a lightweight model, YOLOv8-FSD, based on YOLOv8. By introducing the FasterNet network to replace the original backbone network, computational complexity and memory access are reduced. A thin neck structure designed based on hybrid convolution technology is adopted to reduce model parameters and computational load further. A lightweight dynamic feature upsampling operator improves the feature map quality. Additionally, the regularized Gaussian distribution distance loss function is used to enhance the detection ability for small target defects. Experimental results show that the YOLOv8-FSD lightweight algorithm improves detection accuracy while significantly reducing the number of parameters and computational requirements compared to the original algorithm. This improvement provides an efficient, accurate, and lightweight solution for PV cell defect detection.

关键词： photovoltaic cell defect detection YOLOv8 lightweighting FasterNet

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Systematic and comprehensive insights into HIF-1 stabilization under normoxic conditions: implications for cellular adaptation and therapeutic strategies in cancer

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CELLULAR & MOLECULAR BIOLOGY LETTERS 2025年第1期30卷 1-39页

作者： Zhang, Jiayi Yao, Mingxuan Xia, Shiting Zeng, Fancai Liu, Qiuyu Southwest Med Univ Sch Pharm Luzhou 646000 Peoples R China Southwest Med Univ Sch Basic Med Sci Lab Biochem & Mol Biol Luzhou 646000 Peoples R China Southwest Med Univ Sch Clin Med Luzhou 646000 Peoples R China

Hypoxia-inducible factors (HIFs) are essential transcription factors that orchestrate cellular responses to oxygen deprivation. HIF-1 alpha, as an unstable subunit of HIF-1, is usually hydroxylated by prolyl hydroxylase domain enzymes under normoxic conditions, leading to ubiquitination and proteasomal degradation, thereby keeping low levels. Instead of hypoxia, sometimes even in normoxia, HIF-1 alpha translocates into the nucleus, dimerizes with HIF-1 beta to generate HIF-1, and then activates genes involved in adaptive responses such as angiogenesis, metabolic reprogramming, and cellular survival, which presents new challenges and insights into its role in cellular processes. Thus, the review delves into the mechanisms by which HIF-1 maintains its stability under normoxia including but not limited to giving insights into transcriptional, translational, as well as posttranslational regulation to underscore the pivotal role of HIF-1 in cellular adaptation and malignancy. Moreover, HIF-1 is extensively involved in cancer and cardiovascular diseases and potentially serves as a bridge between them. An overview of HIF-1-related drugs that are approved or in clinical trials is summarized, highlighting their potential capacity for targeting HIF-1 in cancer and cardiovascular toxicity related to cancer treatment. The review provides a comprehensive insight into HIF-1's regulatory mechanism and paves the way for future research and therapeutic development.

关键词： HIF-1 Normoxia Pseudohypoxia Mechanisms Cancer Cellular response Target therapy

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Treatment of atherosclerosis by biomimetic responsive-targeting hybrid nanoparticles enabled by genetically engineering cell membranes and nucleic acid nanostructures for atorvastatin delivery

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CHEMICAL ENGINEERING JOURNAL 2025年 511卷

作者： Chen, Tianyu Lv, Weitong Yang, Mengxi Jiang, Yuhuan Xiao, Dexuan Qin, Xin Sun, Qiang Lin, Yunfeng Sichuan Univ West China Hosp Stomatol Natl Ctr Stomatol Natl Clin Res Ctr Oral DisState Key Lab Oral Dis Chengdu 610041 Sichuan Peoples R China Sichuan Prov Engn Res Ctr Oral Biomat Chengdu 610041 Sichuan Peoples R China Shanghai Jiao Tong Univ Natl Ctr Translat Med Shanghai 200240 Peoples R China

Cardiovascular disease (CVD) is a common disease worldwide with high morality, with atherosclerosis (AS) being a primary pathological driver. Current pharmacological treatments for AS, particularly statins used for anti-inflammatory and anti-oxidant purposes, exhibit limited therapeutic efficacy due to low utilization rates. In this study, we developed a biomimetic drug delivery system integrating genetically modified cell membranes and an encapsulated tetrahedral framework nucleic acid-based carrier loaded with atorvastatin. This multifunctional system, termed tFNA-AT (TAT for short), enables ROS-responsive drug release and inflammation targeting and exerts anti-inflammatory and lipid-eliminating effects. The shell of the hybrid nanoparticle is fabricated by merging a genetically engineered cell membrane that constitutively expresses very late antigen-4 (VLA-4) with synthetic ROS-responsive liposomes. The specific affinity between vascular cell adhesion molecule-1 (VCAM-1) and (VLA-4) guides the shell to target inflamed sites, where ROS-triggered drug release enhances therapeutic precision. Moreover, the incorporation of tFNAs enhances atorvastatin's pharmacokinetics and targeting ability towards inflammation, synergistically improving therapeutic efficacy. Compared to traditional drug formulations, these membrane-coated hybrid nanoparticles offer considerable advantages such as precise delivery, improved pharmacokinetics, controlled drug release, and excellent biocompatibility, presenting a promising therapeutic strategy for AS.

关键词： Genetically engineered cell membrane Tetrahedral framework nucleic acids (tFNAs) Drug delivery Inflammation targeting Atherosclerosis Vascular cell adhesion molecule-1 (VCAM-1)

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Conformational and Solvent Effects on the Photoinduced Electron Transfer Dynamics of a Zinc Phthalocyanine-Benzoperylenetriimide Conjugate: A Nonadiabatic Dynamics Simulation

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CHEMPHYSCHEM 2025年第2期26卷 e202400631页

作者： Liu, Sha-Sha Wei, Xin Zheng, Yan Liu, Shuai Xu, Dong-Hui Li, Laicai Cui, Ganglong Liu, Xiang-Yang Sichuan Normal Univ Coll Chem & Mat Sci Chengdu 610068 Peoples R China Beijing Normal Univ Coll Chem Key Lab Theoret & Computat Photochem Minist Educ Beijing 100875 Peoples R China

Herein, we employed a combination of static electronic structure calculations and nonadiabatic dynamics simulations at linear-response time dependent density functional theory (LR-TDDFT) level with the optimally tuned range-separated hybrid (OT-RSH) functional to explore the ultrafast photoinduced dynamics of a zinc phthalocyanine-benzoperylenetriimide (ZnPc-BPTI) conjugate. Due to the flexibility of the linker, we identified two major conformations: the stacked conformation (ZnPc-BPTI-1) and the extended conformation (ZnPc-BPTI-2). Since the charge transfer states are much lower than the lowest local excitation in ZnPc-BPTI-1, which is contrary to ZnPc-BPTI-2, the ultrafast electron transfer (similar to 3.6 ps) is only observed in the nonadiabatic simulations of ZnPc-BPTI-1 upon local excitation around the absorption maximum of ZnPc. However, when considering the solvent effects in benzonitrile: the lowest S-1 states are both charge transfer states from ZnPc to BPTI for different conformers. Subsequent nonadiabatic dynamics simulations indicate that both conformers experience ultrafast electron transfer in benzonitrile with two time constants of 90 [100] fs and 1.40 [1.43] ps. Our present work not only agrees well with previous experimental study, but also points out the important role of conformational changes and solvent effects in regulating the photodynamics of organic donor-acceptor conjugates.

关键词： Donor-acceptor conjugates ZnPc-BPTI Solvent effects LR-TDDFT Nonadiabatic dynamics simulation

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