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Investigation of MXene nanosheets based radio-frequency electronics by skin depth effect

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Nano research 2024年第4期17卷 3061-3067页

作者： Rongguo Song Yunfa Si Wei Qian Haoran Zu Bilei Zhou Qinglei Du Daping He Yongliang Wang Air Force early Warning Academy Wuhan 430019China Hubei Engineering research center of RF-Microwave Technology and Application Wuhan University of TechnologyWuhan 430070China Hainan research Institute Wuhan University of TechnologySanya 572000China

Various new conductive materials with exceptional properties are utilized for the preparation of electronic devices.Achieving ultra-high conductivity is crucial to attain excellent electrical performance.However,there is a lack of systematic research on the impact of conductor material thickness on device performance.Here,we investigate the effect of conductor thickness on power transmission and radiation in radio-frequency(RF)and microwave electronics based on MXene nanosheets material transmission lines and antennas.The MXene transmission line with thickness above the skin depth exhibits a good transmission coefficient of approximately-3 dB,and the realized gain of MXene antennas exceeds 2 dBi.Additionally,the signal transmission strength of MXene antenna with thickness above the skin depth is higher than 5-μm MXene antenna approximately 5.5 dB.Transmission lines and antennas made from MXene materials with thickness above the skin depth exhibit stable and reliable performance,which has significant implications for obtaining high-performance RF and microwave electronics based on new conductive materials.

关键词： MXene film radiao-frequency electronics antenna transmission line skin depth

Comparison of ERA5 turbulent fluxes at the air-sea interface with measurements from a wave-following platform

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Atmospheric and Oceanic Science Letters 2024年第3期 34-38页

作者： Sa?d Benjeddou Denis Bourras Christopher Luneau Aix Marseille Université National Center for Scientific ResearchMediterranean Institute of Oceanography Observatory of the Sciences of the universe Pythéas Institute National Center for Scientific Research

Turbulent fluxes at the air-sea interface were estimated with data collected in 2011-2020 with a low-profile platform named OCARINA during eight experiments in five regions:2011,2015,and 2016 in the Iroise Sea;2012 in the tropical Atlantic;2014 in the Chilie-Peru upwelling;2017 and 2018 in the Mediterranean Sea,and 2018 and 2020 in Barbados.The observations were carried out with moderate winds(2-10 m s-1) and average wave heights of 1.5 m.In this study,the authors used the fluxes calculated by the bulk method using OCARINA-sampled data as the input.These data can validate the fluxes estimated from ERAS reanalysis data.The OCARINA and ERA5 data were taken concomitantly.To do this,the authors established an algorithm to extract the OCARINA data as closely as possible to the reanalysis data in time and position.The measurements of the OCARINA platform can conclude on the relevance of the widely used reanalysis data.

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The Impact of Regular Diet Recovery on Postoperative Rehabilitation After Elective Cesarean Section

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Maternal-Fetal Medicine 2024年第2期6卷 78-83页

作者： Caihong Hu Kuilin Fei Yuelan Liu Xiaoe Jiang Wenjing Yong Weishe Zhang Ping Li Department of Obstetrics Xiangya HospitalCentral South UniversityChangsha 410008China Hunan Engineering research center of early Life Development and Disease Prevention Xiangya HospitalCentral South UniversityChangsha 410008China

Objective To determine the role of regular diet recovery after restoration of normal muscle strength of both lower extremities in promoting postoperative recovery in women undergoing elective cesarean section.Methods This was a prospective observational cohort study.Patients who underwent elective cesarean section at Xiangya Hospital,Central South University,from October 2022 to December 2022,were categorized into two groups based on the duration of postoperative fasting:the observation group resumed eating after regaining lower extremity muscle strength,while the control group adhered to traditional postoperative fasting guidelines,waiting 6 hours before eating.Primary outcomes included postoperative pain levels assessed by visual analog scale(VAS)pain scores and time to first flatus.Demographic characteristics,time to first lactation,hospital stay length,and patient satisfaction were also assessed.Statistical analysis was conducted using Student’s t test and Chi-squared test,with significance set at P0.05).Conclusion Food intake after restoration of lower extremity muscle strength improves first flatus,relieves postope

关键词： Obstetrics Cesarean section early food intake

The Short-Duration Heavy Rainfall in Different Quadrants of Northeast China Cold Vortices

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Journal of Meteorological research 2024年第2期38卷 321-338页

作者： Lei YANG Yongguang ZHENG Liaoning Meteorological Disaster Monitoring and early Warning center Shenyang 110166 National Meteorological Centre China Meteorological AdministrationBeijing 100081 China Meteorological Administration Tornado Key Laboratory Foshan 528315

The Northeast China cold vortex(NCCV)is one of the main synoptic-scale systems causing short-duration heavy rainfall(SDHR)in Northeast China.Environmental conditions(e.g.,water vapor,instability,and vertical wind shear)are known to be distinctly different over the four quadrants of NCCVs,rendering prediction of the SDHR related to NCCVs(NCCV_SDHR)more challenging.Based on 5-yr hourly rainfall observations from 3196 automatic weather stations and ERA5 reanalysis data,10,232 NCCV_SDHR events were identified and divided into four quadrant groups according to their relative position to the center of the NCCV(CVC).The results show that the southeast quadrant features the highest frequency of SDHR,with stronger intensity,longer duration,and wider coverage;and the SDHR in different quadrants presents different formation mechanisms and varied temporal evolution.A new coordinate system is established relative to the CVC that uses the CVC as the origin and the radius of the NCCV(r CV)as the unit distance.In this new coordinate system,all of the NCCV_SDHR events in the 5-yr study period are synthesized.It is found that the occurrence frequency of NCCV_SDHR initially increases and then decreases with increasing distance from the CVC.The highest frequency occurs mainly between 0.8 and 2.5 times r CV from the CVC in the southeast quadrant.This can be attributed to the favorable conditions,such as convergence of the low-level shear line and abundant water vapor,which are concentrated in this region.Furthermore,high-frequency NCCV_SDHR larger than 50 mm(NCCV_SDHR50)is observed to be closer to the CVC.When NCCV_SDHR50occurs,the NCCV is in closer proximity to the subtropical high,resulting in stronger low-level convergence and more abundant water vapor.Additionally,there are lower lifting condensation levels and stronger 0-6-and 0-1-km vertical wind shears in these environments.These findings provide a valuable reference for more accurate prediction of NCCV_SDHR.

关键词： Northeast China cold vortex short-duration heavy rainfall statistical characteristics environmental conditions

Near real-time gravitational wave data analysis of the massive black hole binary with TianQin

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 175-186页

作者： Hong-Yu Chen Xiang-Yu Lyu En-Kun Li Yi-Ming Hu MOE Key Laboratory of TianQin Mission TianQin Research Center for Gravitational Physics&School of Physics and AstronomyFrontiers Science Center for TianQinGravitational Wave Research Center of CNSASun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

Space-borne gravitational wave(GW)detectors can detect the merger of massive black holes.The early warning and localization of GW events before merging can be used to inform electromagnetic telescopes and conduct multimessenger observations.However,this requires real-time data transmission and analysis capabilities.The geocentric orbit of the space-borne GW detector Tian Qin makes it possible to conduct real-time data transmission.In this study,we develop a search and localization pipeline for massive black hole binaries(MBHBs)with Tian Qin under both regular and real-time data transmission modes.We demonstrate that,with real-time data transmission,MBHBs can be accurately localized on the fly.With the approaching merger,each analysis can be finished in only 40 min.For an MBHB system at a distance of 1 Gpc,if we receive data every hour,then we can pinpoint its location to within less than 1 deg^(2)on the final day before the merger.

关键词： gravitational wave detectors and experiments black holes data analysis algorithms and implementation data management

An end‐to‐end infant brain parcellation pipeline

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Intelligent Medicine 2024年第2期4卷 65-74页

作者： Limei Wang Yue Sun Weili Lin Gang Li Li Wang Department of Radiology and Biomedical research Imaging center UNC-Chapel HillNew Caledonia27599USA

Objective Accurate infant brain parcellation is crucial for understanding early brain development;however,it is challenging due to the inherent low tissue contrast,high noise,and severe partial volume effects in infant magnetic resonance images(MRIs).The aim of this study was to develop an end-to-end pipeline that enabled accurate parcellation of infant brain MRIs.Methods We proposed an end-to-end pipeline that employs a two-stage global-to-local approach for accurate parcellation of infant brain MRIs.Specifically,in the global regions of interest(ROIs)localization stage,a combination of transformer and convolution operations was employed to capture both global spatial features and fine texture features,enabling an approximate localization of the ROIs across the whole brain.In the local ROIs refinement stage,leveraging the position priors from the first stage along with the raw MRIs,the boundaries of the ROIs are refined for a more accurate parcellation.Results We utilized the Dice ratio to evaluate the accuracy of parcellation results.Results on 263 subjects from National Database for Autism research(NDAR),Baby Connectome Project(BCP)and Cross-site datasets demonstrated the better accuracy and robustness of our method than other competing methods.Conclusion Our end-to-end pipeline may be capable of accurately parcellating 6-month-old infant brain MRIs.

关键词： Infant brain parcellation Isointense magnetic resonance image Convolutional neural networks Transformer

Adaptive ultra-hypofractionated whole-pelvic radiotherapy in high-risk and very high-risk prostate cancer on 1.5-Tesla MR-Linac:Estimated delivered dose and early toxicity results

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Chronic Diseases and Translational Medicine 2024年第1期10卷 51-61页

作者： Linrui Gao Ran Wei Shirui Qin Yuan Tian Wenlong Xia Yongwen Song Shulian Wang Hui Fang Yu Tang Hao Jing Yueping Liu Yuan Tang Shunan Qi Bo Chen Yexiong Li Nianzeng Xing Ningning Lu Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina GCP center/Clinical research center National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Urology State Key Laboratory of Molecular OncologyNational Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Background: Magnetic resonance(MR)-guided ultra-hypofractionated radiotherapy with whole-pelvic irradiation(UHF-WPRT)is a novel approach to radiotherapy for patients with high-risk(HR)and very high-risk(VHR)prostate cancer(PCa).However,the inherent complexity of adaptive UHF-WPRT might inevitably result in longer on-couch time.We aimed to estimate the delivered dose,study the feasibility and safety of adaptive UHF-WPRT on a 1.5-Tesla MR-Linac.Methods: Ten patients with clinical stage T3a-4N0-1M0-1c PCa,who consecutively received UHF-WPRT,were enrolled prospectively.The contours of the target and organ-at-risks on the position verification-MR(PV-MR),beam-on 3D-MR(Bn-MR),and post-MR(after radiotherapy delivery)were derived from the pre-MR data by deformable image registration.The physician then manually adjusted them,and dose recalculation was performed accordingly.GraphPad Prism 9(GraphPad Prism Software Inc.)was utilized for conducting statistical analyses.Results: In total,we collected 188 MR scans(50 pre-MR,50 PV-MR,44 Bn-MR,and 44 post-MR scans).With median 59 min,the mean prostate clinical target volume(CTV)-V_(100%)was 98.59%±2.74%,and the mean pelvic CTVp-V_(100%)relative percentages of all scans was 99.60%±1.18%.The median V29 Gy change in the rectal wall was−2%(−18%to 20%).With a median follow-up of 9 months,no patient had acute Common Terminology Criteria for Adverse Events(CTCAE)grade 2 or more severe genitourinary(GU)or gastrointestinal(GI)toxicities(0%).Conclusion: UHF-RT to the prostate and the whole pelvis with concomitant boost to positive nodes using an Adapt-To-Shape(ATS)workflow was technically feasible for patients with HR and VHR PCa,presenting only mild GU and GI toxicities.The estimated target dose during the beam-on phase was clinically acceptable based on the 3D-MR-based dosimetry analysis.Clinical trial registration Chinese Clinical Trial Registry ChiCTR2000033382.

关键词： dosimetry hypofractionation magnetic resonance imaging prostate cancer radiation dose radiotherapy

Endoscopic features and treatments of gastric cystica profunda

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World Journal of Gastroenterology 2024年第7期30卷 673-684页

作者： Zi-Han Geng Yan Zhu Pei-Yao Fu Yi-Fan Qu Wei-Feng Chen Xia Yang Ping-Hong Zhou Quan-Lin Li Endoscopy center and Endoscopy research Institute Zhongshan HospitalFudan UniversityShanghai 200032China

BACKGROUND Gastric cystica profunda(GCP)represents a rare condition characterized by cystic dilation of gastric glands within the mucosal and/or submucosal layers.GCP is often linked to,or may progress into,early gastric cancer(EGC).AIM To provide a comprehensive evaluation of the endoscopic features of GCP while assessing the efficacy of endoscopic treatment,thereby offering guidance for diagnosis and treatment.METHODS This retrospective study involved 104 patients with GCP who underwent endoscopic resection.Alongside demographic and clinical data,regular patient followups were conducted to assess local recurrence.RESULTS Among the 104 patients diagnosed with GCP who underwent endoscopic resection,12.5%had a history of previous gastric procedures.The primary site predominantly affected was the cardia(38.5%,n=40).GCP commonly exhibited intraluminal growth(99%),regular presentation(74.0%),and ulcerative mucosa(61.5%).The leading endoscopic feature was the mucosal lesion type(59.6%,n=62).The average maximum diameter was 20.9±15.3 mm,with mucosal involvement in 60.6%(n=63).Procedures lasted 73.9±57.5 min,achieving complete resection in 91.3%(n=95).Recurrence(4.8%)was managed via either surgical intervention(n=1)or through endoscopic resection(n=4).Final pathology confirmed that 59.6%of GCP cases were associated with EGC.Univariate analysis indicated that elderly males were more susceptible to GCP associated with EGC.Conversely,multivariate analysis identified lesion morphology and endoscopic features as significant risk factors.Survival analysis demonstrated no statistically significant difference in recurrence between GCP with and without EGC(P=0.72).CONCLUSION The findings suggested that endoscopic resection might serve as an effective and minimally invasive treatment for GCP with or without EGC.

关键词： Gastric cystica profunda early gastric cancer Endoscopic features Endoscopic resection Endoscopy

Emerging roles of exosomes in oral diseases progression

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International Journal of Oral Science 2024年第1期16卷 36-51页

作者： Jiayi Wang Junjun Jing Chenchen Zhou Yi Fan State Key Laboratory of Oral Diseases&National center for Stomatology&National Clinical research center for Oral Diseases&Department of Cariology and Endodontics West China Hospital of StomatologySichuan UniversityChengduChina State Key Laboratory of Oral Diseases&National center for Stomatology&National Clinical research center for Oral Diseases&West China Hospital of Stomatology Sichuan UniversityChengduChina State Key Laboratory of Oral Diseases&National center for Stomatology&National Clinical research center for Oral Diseases&Department of Pediatric Dentistry West China Hospital of StomatologySichuan UniversityChengduChina

Oral diseases, such as periodontitis, salivary gland diseases, and oral cancers, significantly challenge health conditions due to their detrimental effects on patient's digestive functions, pronunciation, and esthetic demands. Delayed diagnosis and non-targeted treatment profoundly influence patients' prognosis and quality of life. The exploration of innovative approaches for early detection and precise treatment represents a promising frontier in oral medicine.

关键词： diseases diagnosis salivary