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Time difference auto-extraction methods for in situ sound speed measurements in seafloor sediments

GEOPHYSICAL PROSPECTING 2024年第6期72卷 2261-2273页

作者： Hua, Qingfeng Wang, Jingqiang Li, Guanbao Zhang, Linqing Sun, Lei Dong, wuwen MNR Inst Oceanog 1 Key Lab Marine Geol & Metallogeny Qingdao 266061 Peoples R China Qingdao Marine Sci & Technol Ctr Lab Marine Geol Qingdao Shandong Peoples R China Qingdao Baseman Elect Technol Co Ltd Qingdao Shandong Peoples R China

The in situ acoustic measurement of seafloor sediment is an important technical means to obtain the acoustic parameters of seafloor. The time-of-flight method is commonly used to calculate the sound speed in seafloor sediment. Accurate identification of signal feature points is essential for determining travel time or travel time difference of acoustic signals. However, the precise identification of feature points, such as the take-off point of the first wave of a sound wave signal, is challenging. The conventional manual identification method is inefficient and prone to errors. The development of a feature point auto-identification method is imperative for accurately calculating the travel time of acoustic signals. In this study, we employed the cross-correlation method, the level threshold method and the short window-long window energy ratio method to extract the acoustic travel time differences and calculate the sound speeds in seawater and in seafloor sediment. We then analysed the effectiveness of these calculated results. The sound speeds in seawater obtained through the aforementioned methods were compared with the sound speeds measured using a sound velocity profiler. The comparison revealed that these processing methods exhibit a high level of accuracy. The sound speed results in sediments show that the programme-based auto-identification methods significantly reduce the standard deviation compared to the manual identification method. This study successfully assessed the processing accuracy of different methods and expanded the processing methods for in situ acoustic signals of seafloor sediments.

关键词： in situ measurement seafloor sediment signal processing method sound speed time difference auto-extraction

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A novel method for accurate simulations of concentrated forces in finite element analysis

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ENGINEERING WITH COMPUTERS 2022年第3期38卷 2791-2803页

作者： Chen, Junwei Zhou, Xiaoping Yao, wuwen Zi, Weiyi Wuhan Univ Sch Civil Engn Wuhan 430072 Peoples R China Chongqing Univ Sch Civil Engn Chongqing 400045 Peoples R China

In this paper, the analytical displacement solution at the point of the application of a concentrated force is derived using elastic mechanics. Then, the concentrated-force asymptotic function is obtained. Next, by introducing the concentrated-force asymptotic functions into finite element analysis, a method of simulating concentrated forces is developed. The proposed method can obtain an accurate stress field without any mesh refinement at the point of the application of a concentrated force. Meanwhile, the proposed method has considered the effect of the direction of the concentrated forces. The numerical tests reveal that the proposed method is convergent, accurate and feasible for obtaining satisfactory results.

关键词： Concentrated force Numerical simulation Force transmission Finite element analysis Crack problem

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Interplay of student characteristics multidimensional engagement and influencing factors in online computer science education

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SCIENTIFIC REPORTS 2025年第1期15卷 1-15页

作者： Zhang, wuwen Guan, Yurong Hu, Zhihua Wang, Chencheng Lu, Douming Lu, Huaiyu Huanggang Normal Univ Coll Educ Huanggang 438000 Peoples R China Huanggang Normal Univ Coll Comp Sci Huanggang 438000 Peoples R China Donghua Grp Dongguan Guangdong Peoples R China Shishi Expt Sch Foshan Guangdong Peoples R China

Digital technology is reshaping the landscape of higher education, especially in the field of computer science. As digital platforms become central to the learning process, understanding student engagement in these continuously evolving environments is increasingly vital. This study explores the current state of online learning among undergraduate computer science students, investigates factors influencing their engagement, and proposes strategies to enhance online education. The research framework is grounded in the TPACK model, behaviorist learning theory, learning engagement theory, and situated cognition learning theory, encompassing student characteristics, multidimensional online learning engagement, and key influencing factors. Data on participants' basic attributes, levels of engagement, and the major determinants of these engagement levels were collected via a questionnaire survey. Analyses using SPSS 25.0-employing t-tests, ANOVA, and Pearson correlation-revealed significant trends and relationships. Findings show a notable positive correlation between the duration of online learning and overall engagement, whereas gender, home location, and academic major exerted relatively limited influence. Subjective intention, attitude, and motivation emerged as crucial determinants, and interactions with instructors and Peers-reinforced by teaching approaches and feedback-played an essential role in fostering emotional involvement. Building on these insights, the study recommends initiatives to strengthen self-motivation, nurture meaningful online interactions, enhance technical support systems, and reinforce mechanisms for assessing learning outcomes. This work provides empirical evidence for a deeper understanding of online education while indicating directions for ongoing improvement.

关键词： Online learning Learning engagement Influencing factors Computer science major

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Fuzi alleviates cold-related rheumatoid arthritis via regulating gut microbiota and microbial bile acid metabolism

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CHINESE MEDICINE 2025年第1期20卷 1-18页

作者： Liu, Juan Zhang, Dandan Zhou, Yaochuan Wu, Jinlu Feng, wuwen Peng, Cheng Chengdu Univ Tradit Chinese Med Sch Pharm State Key Lab Southwestern Chinese Med Resources Chengdu 611137 Peoples R China Hosp Chengdu Univ Tradit Chinese Med TCM Regulating Metab Dis Key Lab Sichuan Prov Chengdu 610032 Peoples R China Chengdu Univ Tradit Chinese Med Minist Educ Standardizat Chinese Med Key Lab Chengdu 611137 Peoples R China

BackgroundRheumatoid arthritis (RA) with cold pattern is an important type of RA according to the theory of traditional Chinese medicine. Fuzi (also known as the lateral roots of Aconitum carmichaelii Debx.) represents a typical traditional Chinese medicine that has been clinically used for treatment of the RA especially cold-related RA for thousands of years, yet its mechanism remains *** purpose of the research was to study the therapeutic effects of Fuzi on cold-related RA, and to investigate the mechanism of its ***, we investigated the pharmacological effects of Fuzi on cold-related RA using micro-CT, histopathological analysis, and inflammatory cytokine test. Then, a gut microbiota composition analysis in combination with fecal microbiota transplantation were used to confirm the role of gut microbiota in the therapeutic effects of Fuzi. Further, targeted bile acid metabolomics was used to screen the possible differential microbial bile acids involved in the mechanism of Fuzi. In vitro bioactivity analysis of differential bile acids was used to assess their anti-inflammation activity. Finally, western blot was used to investigate the signaling pathways of Fuzi in reducing the inflammation of cold-related *** results showed that Fuzi alleviates cold-related RA by improving arthritis index, paw swelling, bone damage, and inflammatory cytokines. In addition, the ameliorative effect of Fuzi is dependent on gut microbiota such as the taxa Lachnospiraceae and Ruminococcaceae. Targeted analysis of fecal and serum bile acids showed that TCA and THDCA were the main differential metabolites. In vitro, TCA and THDCA showed anti-inflammation effects on RAW264.7 cells. Western blot showed that Fuzi regulates TGR5-cAMP-PKA signaling and NLRP3 inflammasome to reduce cold-related ***, our results demonstrated that Fuzi could regulate gut microbiota and microbial bile acid metabolism, the microbial metabolite THDCA

关键词： Fuzi Rheumatoid arthritis Gut microbiota TGR5-cAMP-PKA signaling NLRP3 inflammasome

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Enhanced Thermal and Electrical Properties of Photosensitive Resin Matrix Composites with Hexagonal Boron Nitride Nanosheets

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JOURNAL OF INORGANIC AND ORGANOMETALLIC POLYMERS AND MATERIALS 2023年第2期33卷 319-327页

作者： Chen, Caifeng Shao, Mingwei Liu, Kai Zhong, wuwen Djassi, Iala Wang, Andong Jiangsu Univ Sch Mat Sci & Engn Zhenjiang 212013 Jiangsu Peoples R China

Hexagonal boron nitride nanosheets (BNNS) and their photosensitive resin-based composites have excellent thermal conductivity, thermal stability, and electrical properties, making them promising applications in electronic devices and packaging. In this paper, BNNS were exfoliated by hydrothermal method, and BNNS/photosensitive resin composite was prepared by ultraviolet curing. The enhancement effect of BNNS on the thermal stability and electrical properties of the composites was studied. The result showed that few-layer BNNS with hexagonal structure were obtained after hydrothermal exfoliation of hexagonal boron nitride (h-BN), part of the B-N bond in BNNS formed a covalent bond with the photosensitive resin matrix. Both of chemical interface and overlapping interface formed between BNNS and the matrix help to form a better and tighter interface, which effectively improves the thermal stability of the photosensitive resin. As the mass percentage of BNNS increases, the temperature required for the decomposition of BNNS/photosensitive resin composites increases, and the relative permittivity also increases significantly because of the interface polarization. When the content of BNNS reaches 10 wt%, it reaches the highest value of 7.623 at the frequency of 1 kHz. Due to the high surface area of the few-layer BNNS, a network structure is formed in the matrix, which improves the breakdown strength of the photosensitive resin.

关键词： Hexagonal boron nitride Nanosheets Hydrothermal method Photosensitive resin Composite

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Real-Time Monitoring of a Single Molecule in Sub-nanometer Space by Dynamic Surface-Enhanced Raman Spectroscopy

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JOURNAL OF PHYSICAL CHEMISTRY LETTERS 2023年第39期14卷 8726-8733页

作者： Yan, wuwen Chen, Siyu Li, Pan Dong, Ronglu Shin, Hyun-Hang Yang, Liangbao Chinese Acad Sci Hefei Inst Phys Sci Inst Hlth & Med Technol Hefei 230031 Anhui Peoples R China Univ Sci & Technol China Hefei 230026 Anhui Peoples R China Chinese Acad Sci Hefei Canc Hosp Dept Pharm Hefei 230031 Anhui Peoples R China Seoul Natl Univ Dept Chem Seoul 08826 South Korea

In biology and chemistry, the ultimate goal is to monitor single molecules without labels. However, long-term monitoring of label-free molecules remains a challenge. Here, on the basis of the photothermal effect of gold nanorods (GNRs), we developed a platform for monitoring of a single molecule employing surface-enhanced Raman spectroscopy (SERS). Laser re-irradiation forms 1.0 nm gaps between GNRs, allowing us to observe single crystal violet (CV) molecules blinking for up to 4 min with dynamic surface-enhanced Raman spectroscopy (D-SERS). Bianalyte experiments confirm single-molecule features at CV concentrations of 10(-14) M. Combining density functional theory (DFT) calculations with a free CV molecule observed in millisecond D-SERS, we propose that CV molecules can be confined to sub-nanometer space and the orientation of an individual CV moving in the range of 50-90(degrees) can be dynamically captured by D-SERS. This will provide a novel idea for effective exploration of the temporal and spatial dynamic processes of different reactions.

关键词： Interfaces Lasers Molecules Neurophysiology Raman spectroscopy

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Revisiting traditional Chinese exercise in prediabetes: effects on glycaemic and lipid metabolism - a systematic review and meta-analysis

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DIABETOLOGY & METABOLIC SYNDROME 2025年第1期17卷 1-18页

作者： Yan, Ruixiang Peng, wuwen Lu, Di He, Jiaxin Sun, Jian Guan, Lingju Liu, Shufang Li, Duanying Guangzhou Sport Univ Sch Athlet Training Guangzhou Peoples R China Guangzhou Sport Univ Dept Sport & Hlth Guangzhou Peoples R China Guangdong Prov Inst Sports Sci Guangzhou Peoples R China

Background and objectivesMost existing studies have primarily focused on the effects of Traditional Chinese Exercises (TCEs) on glycemic control in individuals with prediabetes, while specific recommendations for managing dyslipidemia in this population remain insufficient. Moreover, there is a lack of systematic research and conclusive evidence regarding the optimal exercise dose required to achieve metabolic improvements in individuals with prediabetes. Therefore, this meta-analysis aims to comprehensively evaluate the efficacy of TCEs in improving glycemic and lipid profiles in individuals with prediabetes and to explore the potential impact of exercise dose on these metabolic parameters. MethodsA comprehensive search of six databases (PubMed, Web of Science, Cochrane Library, Embase, CNKI, and WanFang Data) followed PRISMA guidelines to identify randomized controlled trials (RCTs) on TCEs (e.g., "Tai Chi," "Yijinjing," "Baduanjin") and prediabetes (e.g., "impaired glucose tolerance," "impaired glucose regulation") published up to November 10, 2024. Three reviewers independently screened studies, extracted data, and assessed bias risk. Meta-analysis and subgroup/meta-regression analyses were conducted using Stata 17 software. The review protocol is registered in PROSPERO (CRD42024615150). ResultsA total of 15 studies involving 1,839 participants were included. The meta-analysis revealed that TCEs significantly improved HbA1c (MD = -0.28%;95% CI: -0.38% to -0.18%;P = 0.001), FBG (MD = -0.44 mmol/L;95% CI: -0.53 to -0.34 mmol/L;P < 0.001), 2hPG (MD = -1.16 mmol/L;95% CI: -1.48 to -0.85 mmol/L;P < 0.001), TC (MD = -0.31 mmol/L;95% CI: -0.50 to -0.11 mmol/L;P = 0.002), TG (MD = -0.28 mmol/L;95% CI: -0.50 to -0.06 mmol/L;P = 0.012), and HDL (MD = -0.28 mmol/L;95% CI: -0.50 to -0.06 mmol/L;P = 0.012) compared to control groups. ConclusionsTCEs significantly improve prediabetics' blood glucose and lipid levels. The recommended exercise regimen is 30-50 min per session,

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Effect of unilateral and bilateral plyometric training on jumping, sprinting, and change of direction abilities: a meta-analysis

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BMC SPORTS SCIENCE MEDICINE AND REHABILITATION 2025年第1期17卷 1-17页

作者： Zhang, Zhanming Qu, Wenhao Peng, wuwen Sun, Jian Yue, Jiyang Guan, Lingju Lu, Min Li, Duanying Guangzhou Sport Univ Grad Sch Guangzhou Guangdong Peoples R China Guangzhou Sport Univ Sch Athlet Training 1268 Guangzhou Ave Cent Guangzhou 510500 Guangdong Peoples R China Guangdong Prov Inst Sports Sci Guangzhou Guangdong Peoples R China Guangzhou Sport Univ Sch Wushu Guangzhou Guangdong Peoples R China Guangdong Prov Key Lab Human Sports Performance Sc Guangzhou Guangdong Peoples R China

Background Plyometric training is a commonly employed method to enhance explosive strength in athletes. However, to date, no study has provided a comprehensive and systematic evaluation of the effects of unilateral (UNI) versus bilateral (BI) plyometric training. Objectives This meta-analysis investigates the impact of UNI and BI plyometric training on jumping, sprinting, and Change of Direction (COD) abilities. Study eligibility criteria To be eligible for inclusion in the meta-analysis, the study had to be:(1)healthy individuals;(2)UNI and BI plyometric training;(3)conducted on rigid surfaces;(4)the outcome indicators were jumping ability, sprinting, and change of direction ability;(5)randomized controlled trials (RCTs). Study appraisal and synthesis methods We used the random-effects model for meta-analyses. Effect sizes (standardized mean difference), calculated from measures of horizontally oriented performance, were represented by the standardized mean difference and presented alongside 95% confidence intervals (CI). Data sources PubMed, Web of Science, Scopus, ProQuest, CNKI and Google Scholar. Results A total of 11 papers met the inclusion criteria. The meta-analysis revealed that UNI contrast training was more effective than BI contrast training in improving single-leg jump performance (ES = 0.53, 95% CI: 0.02-1.04;Z = 2.05, p = 0.04), double-legs jump performance (ES = -0.07, 95% CI: -0.23-0.09;Z = 0.88, p = 0.38),sprint performance (ES = -0.04, 95% CI: -0.07--0.01;Z = 2.32, p = 0.02), as well as COD (ES = - 0.08, 95% CI: - 0.12 to - 0.03;Z = 3.29, p = 0.001 < 0.01). Conversely, BI contrast training showed a greater effect on bilateral jump performance (ES = -0.07, 95% CI: -0.12--0.03;Z = 3.39, p = 0.0007). Training with low-ground-contact frequencies (LGCF, fewer than 900 contacts) was found to significantly enhance vertical jump performance (ES = 0.64, 95% CI: 0.01-1.27;Z = 2.00, p = 0.05). Conclusions UNI and BI plyometric training offer modality-specif

关键词： Unilateral training Plyometric training Lower Limb Athletic Performance

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Interactions between gut microbiota and berberine,a necessary procedure to understand the mechanisms of berberine

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Journal of Pharmaceutical Analysis 2022年第4期12卷 541-555页

作者： Hao Cheng Juan Liu Yuzhu Tan wuwen Feng Cheng Peng State Key Laboratory of Southwestern Chinese Medicine Resources School of PharmacyChengdu University of Traditional Chinese MedicineChengdu611137China

Berberine(BBR),an isoquinoline alkaloid,has been found in many plants,such as Coptis chinensis Franch and Phellodendron chinense *** BBR has a wide spectrum of pharmacological effects,its oral bioavailability is extremely *** recent years,gut microbiota has emerged as a cynosure to understand the mechanisms of action of herbal *** studies have demonstrated that due to its low bioavailability,BBR can interact with the gut microbiota,thereby exhibiting altered pharmacological ***,no systematic and comprehensive review has summarized these interactions and their corresponding influences on pharmacological ***,we describe the direct interactive relationships between BBR and gut microbiota,including regulation of gut microbiota composition and metabolism by BBR and metabolization of BBR by gut *** addition,the complex interactions between gut microbiota and BBR as well as the side effects and personalized use of BBR are ***,we provide our viewpoint on future research directions regarding BBR and gut *** review not only helps to explain the mechanisms underlying BBR activity but also provides support for the rational use of BBR in clinical practice.

关键词： Berberine Gut microbiota Oral bioavailability Traditional Chinese medicines Short chain fatty acids

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Time-dependent effects of acute stretching on power, balance, and flexibility in contemporary dancers: a randomized crossover trial

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SCIENTIFIC REPORTS 2025年第1期15卷 1-11页

作者： Yan, Ruixiang Lin, Gesheng Peng, wuwen Chen, Yuhuan Sun, Pengpeng Sun, Jian Li, Duanyin Guangzhou Sport Univ Sch Athlet Training Guangzhou Guangdong Peoples R China Guangdong Business & Technol Univ Sch Phys Educ Guangzhou Peoples R China Guangzhou Sport Univ Sch Wushu Guangzhou Peoples R China Guangzhou Sport Univ Guangdong Prov Key Lab Human Sports Performance Sc Guangzhou Peoples R China

To evaluate the acute effects of proprioceptive neuromuscular facilitation (PNF), static (SS) and dynamic (DS) stretching on flexibility, power, and balance in contemporary dancers and to analyze the time-dependent flexibility changes to optimize stretching strategies for training and performance. A randomized crossover trial was conducted with 24 university-level contemporary dancers. In phase one, participants completed sit-and-reach (S&R), countermovement jump (CMJ), and Y-balance (YBT) tests immediately post-stretching. In phase two, only S&R was measured before stretching, immediately after, and at 5, 10, and 15 min post-stretching. PNF (ES = 0.329, p < .001), SS (ES = 0.263, p < .01), and DS (ES = 0.306, p < .01) significantly improved S&R, with PNF and DS being more effective than control (CON) (p < .05). DS and PNF showed progressive improvements over 15 min (p < .01), while SS peaked at 10 min (ES = 0.389, p < .01) before slightly declining (ES = 0.343, p < .01). No significant changes were found in CMJ or YBT (p > .05). For contemporary dancers who require high flexibility, SS, DS, and PNF stretching effectively enhance flexibility within 15 min post-stretching without negatively impacting power or balance.

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