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Trends in Fruit and Vegetable Intake Among the Labor Force Population—China,2010-2018

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China CDC weekly 2024年第18期6卷 401-407,I0008页

作者： Lan Wang Mei Zhang Xiao Zhang Zhenping Zhao Chun Li Mengting Yu Taotao Xue Feng Tan Limin Wang division of Chronic Disease and Risk Factor Surveillance National Center for Chronic and Non-communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Chinese Center for Disease Control and Prevention BeijingChina

Introduction:This research investigates trends pertaining to the prevalence of low fruit and vegetable consumption among the labor force population in *** study considered data derived from four nationally representative cross-sectional ***:The data under review for this study was derived from the China Chronic Disease and Risk Factor Surveillance(CCDRFS)carried out in 2010,2013,2015,and 2018,*** utilized a food frequency questionnaire to evaluate the quantity and frequency of fruit and vegetable *** estimated prevalence of low fruit and vegetable consumption was calculated for each survey,while considering factors such as sex,age,location,and socioeconomic status(SES).Participants’SES was ascertained via latent class analysis,serving to identify distinct classes based on criteria such as education,occupation,and household income per *** regression was deployed to determine the statistical significance of ***:From 2010 to 2018,there was a notable increase in the average daily consumption of vegetables and fruits among the working population,rising from 418.6 g/day to 491.8 g/day(P0.05 for trend).Conclusion:Over the past nine years,there has been a notable decline in the prevalence of low fruit and vegetable consumption among the labor force population in ***,the comparatively deficient intake of fruits and vegetables evident among individuals of lower SES warrants further attention.

关键词： intake occupation utilized

A step to the decentralized real-time timekeeping network

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Chinese Physics B 2024年第1期33卷 183-191页

作者：王芳敏陈雨锋周建华蔺玉亭杨军王波王力军 State Key Laboratory of Precision Space-time Information Sensing Technology Department of Precision InstrumentTsinghua UniversityBeijing 100084China Key Laboratory of Photonic Control Technology Tsinghua UniversityBeijing 100084China Beijing Satellite Navigation Center Beijing 100094China Beijing Institute of Radio Metrology and Measurement Beijing 100854China

The composite time scale(CTS) provides an accurate and stable time-frequency reference for modern science and technology. Conventional CTS always features a centralized network topology, which means that the CTS is accompanied by a local master clock. This largely restricts the stability and reliability of the CTS. We simulate the restriction and analyze the influence of the master clock on the CTS. It proves that the CTS's long-term stability is also positively related to that of the master clock, until the region dominated by the frequency drift of the H-maser(averaging time longer than ~10~5s).Aiming at this restriction, a real-time clock network is utilized. Based on the network, a real-time CTS referenced by a stable remote master clock is achieved. The experiment comparing two real-time CTSs referenced by a local and a remote master clock respectively reveals that under open-loop steering, the stability of the CTS is improved by referencing to a remote and more stable master clock instead of a local and less stable master clock. In this way, with the help of the proposed scheme, the CTS can be referenced to the most stable master clock within the network in real time, no matter whether it is local or remote, making democratic polycentric timekeeping possible.

关键词： frequency synchronization network composite time scale frequency stability democratic timekeeping

An all-polarization-maintaining repetition-tunable erbium-doped passively mode-locked fiber laser

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Chinese Physics B 2013年第10期22卷 299-304页

作者：赵光贞肖晓晟孟飞梅佳伟杨昌喜 State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentsTsinghua University division of time and frequency Metrology National Institute of Metrology

An environmentally stable, repetition rate tunable, all-polarization-maintaining, Er-doped pulse fiber laser with a single-wall carbon nanotubes saturated absorber is demonstrated. The ring laser cavity includes a delay line enabling a tunable repetition rate to vary from 35.52 MHz to 35.64 MHz with continuous mode-locked operation. The laser output parameters confirm that the tunable mode-locked operations are stable. High environmental stability is also confirmed by the -130 dBc/Hz low phase noise, a 70-dB signal-to-noise ratio of radio frequency signals, a low amplitude fluctuation of 5.76 × 10-4, and a low fluctuation of reoetition rate of 12 Hz. The laser shows a high de^ree of oolarization of 93%.

关键词： fiber laser modulation tuning and mode locking nanotubes

Development and validation of a nomogram model for predicting the risk of pre-hospital delay in patients with acute myocardial infarction

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World Journal of Cardiology 2024年第2期16卷 80-91页

作者： Jiao-Yu Cao Li-Xiang Zhang Xiao-Juan Zhou Department of Cardiology The First Affiliated Hospital of USTCDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina

BACKGROUND Acute myocardial infarction(AMI)is a severe cardiovascular disease caused by the blockage of coronary arteries that leads to ischemic necrosis of the *** medical contact is critical for successful AMI treatment,and delays increase the risk of death for ***-hospital delay time(PDT)is a significant challenge for reducing treatment times,as identifying high-risk patients with AMI remains *** study aims to construct a risk prediction model to identify high-risk patients and develop targeted strategies for effective and prompt care,ultimately reducing PDT and improving treatment *** To construct a nomogram model for forecasting pre-hospital delay(PHD)likelihood in patients with AMI and to assess the precision of the nomogram model in predicting PHD *** A retrospective cohort design was employed to investigate predictive factors for PHD in patients with AMI diagnosed between January 2022 and September *** study included 252 patients,with 180 randomly assigned to the development group and the remaining 72 to the validation group in a 7:3 *** risk factors influencing PHD were identified in the development group,leading to the establishment of a nomogram model for predicting PHD in patients with *** model's predictive performance was evaluated using the receiver operating characteristic curve in both the development and validation *** Independent risk factors for PHD in patients with AMI included living alone,hyperlipidemia,age,diabetes mellitus,and digestive system diseases(P<0.05).A characteristic curve analysis indicated area under the receiver operating characteristic curve values of 0.787(95%confidence interval:0.716–0.858)and 0.770(95%confidence interval:0.660-0.879)in the development and validation groups,respectively,demonstrating the model's good discriminatory *** Hosmer–Lemeshow goodness-of-fit test revealed no statistically significant disparity between the an

关键词： Pre-hospital delay Acute myocardial infarction Risk prediction Nomogram

Precision frequency measurement of 1^S0–3^P1 intercombination lines of Sr isotopes

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Chinese Physics B 2015年第1期24卷 208-215页

作者：刘辉高峰王叶兵田晓任洁卢本全徐琴芳谢玉林常宏 CAS Key Laboratory of time and frequency Primary Standards National Time Service Center University of Chinese Academy of Sciences

We report on frequency measurement of the intercombination（5s^2）^1S0–（5s5p）^3P1transition of the four natural isotopes of strontium, including88^Sr（82.58%）,87^Sr（7.0%）,86^Sr（9.86%）, and84^Sr（0.56%）. A narrow-linewidth laser that is locked to an ultra-low expansion（ULE） optical cavity with a finesse of 12000 is evaluated at a linewidth of 200 Hz with a fractional frequency drift of 2.8×10^-13 at an integration time of 1 s. The fluorescence collector and detector are specially designed, based on a thermal atomic beam. Using a double-pass acousto-optic modulator（AOM） combined with a fiber and laser power stabilization configuration to detune the laser frequency enables high signal-to-noise ratios and precision saturated spectra to be obtained for the six transition lines, which allows us to determine the transition frequency *** optical frequency is measured using an optical frequency synthesizer referenced to an H maser. Both the statistical values and the final values, including the corrections and uncertainties, are derived for a comparison with the values given in other works.

关键词： optical frequency measurement strontium intercombination transition

Bioceramic scaffolds with two-step internal/external modification of copper-containing polydopamine enhance antibacterial and alveolar bone regeneration capability

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 65-82页

作者： Xiaojian JIANG Lihong LEI Weilian SUN Yingming WEI Jiayin HAN Shuaiqi ZHONG Xianyan YANG Zhongru GOU Lili CHEN Department of Oral Medicine the Second Affiliated HospitalZhejiang University School of MedicineHangzhou310009China Bio-nanomaterials and Regenerative Medicine Research division Zhejiang–California International Nanosystem InstituteZhejiang UniversityHangzhou310058China

Magnesium-doped calcium silicate(CS)bioceramic scaffolds have unique advantages in mandibular defect repair;however,they lack antibacterial properties to cope with the complex oral ***,for the first time,the CS scaffold was functionally modified with a novel copper-containing polydopamine(PDA(Cu^(2+)))rapid deposition method,to construct internally modified(*P),externally modified(@PDA),and dually modified(*P@PDA)*** morphology,degradation behavior,and mechanical properties of the obtained scaffolds were evaluated in *** results showed that the CS*P@PDA had a unique micro-/nano-structural surface and appreciable mechanical *** the prolonged immersion stage,the release of copper ions from the CS*P@PDA scaffolds was rapid in the early stage and exhibited long-term sustained *** in vitro evaluation revealed that the release behavior of copper ions ascribed an excellent antibacterial effect to the CS*P@PDA,while the scaffolds retained good cytocompatibility with improved osteogenesis and angiogenesis ***,the PDA(Cu^(2+))-modified scaffolds showed effective early bone regeneration in a critical-size rabbit mandibular defect ***,it was indicated that considerable antibacterial property along with the enhancement of alveolar bone regeneration can be imparted to the scaffold by the two-step PDA(Cu^(2+))modification,and the convenience and wide applicability of this technique make it a promising strategy to avoid bacterial infections on implants.

关键词： Copper-containing polydopamine Modification Antibacterial property Bone regeneration Angiogenesis Bioceramic scaffold

First Evaluation and frequency Measurement of the Strontium Optical Lattice Clock at NIM

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Chinese Physics Letters 2015年第9期32卷 17-20页

作者：林弋戈王强李烨孟飞林百科臧二军孙震房芳李天初方占军 division of time and frequency National Institute of Metrology (NIM) Beijing 100013 Department of Precision Instrument Tsinghua University Beijing 100084

An optical lattice clock based on 87Sr is built at National Institute of Metrology （NIM） of China. The systematic frequency shifts of the clock are evaluated with a total uncertainty of 2.3×10-16. To measure its absolute frequency with respect to NIM＇s cesium fountain clock NIM5, the frequency of a flywheel H-maser of NIM5 is transferred to the Sr laboratory through a 50-kin-long fiber. reference frequency of this H-maser, is used for the optical this Sr clock is measured to be 429228004229873.7（1.4）Hz. A fiber optical frequency comb, phase-locked to the frequency measurement. The absolute frequency of

关键词： AOM First Evaluation and frequency Measurement of the Strontium Optical Lattice Clock at NIM

Mid-term outcomes of a kinematically designed cruciate retaining total knee arthroplasty

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World Journal of Orthopedics 2024年第2期15卷 118-128页

作者： Jonathan L Katzman Akram A Habibi Muhammad A Haider Casey Cardillo Ivan Fernandez-Madrid Morteza Meftah Ran Schwarzkopf Department of Orthopedic Surgery Division of Adult Reconstructive SurgeryNYU Langone Orthopedic HospitalNYU Langone HealthNew YorkNY 10010United States

BACKGROUND Advances in implant material and design have allowed for improvements in total knee arthroplasty(TKA)outcomes.A cruciate retaining(CR)TKA provides the least constraint of TKA designs by preserving the native posterior cruciate *** research exists that has examined clinical outcomes or patient reported outcome measures(PROMs)of a large cohort of patients undergoing a CR TKA utilizing a kinematically designed *** was hypothesized that the studied CR Knee System would demonstrate favorable outcomes and a clinically significant improvement in pain and functional *** To assess both short-term and mid-term clinical outcomes and PROMs of a novel CR TKA *** A retrospective,multi-surgeon study identified 255 knees undergoing a TKA utilizing a kinematically designed CR Knee System(JOURNEY™II CR;Smith and Nephew,Inc.,Memphis,TN)at an urban,academic medical institution between March 2015 and July 2021 with a minimum of two-years of clinical follow-up with an orthopedic *** demographics,surgical information,clinical outcomes,and PROMs data were collected via query of electronic medical *** PROMs collected in the present study included the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement(KOOS JR)and Patient-Reported Outcomes Measurement Information System(PROMIS■)*** significance of improvements in mean PROM scores from preoperative scores to scores collected at six months and two-years postoperatively was analyzed using Independent Samples *** Of the 255 patients,65.5%were female,43.8%were White,and patients had an average age of 60.6 *** osteoarthritis(96.9%)was the most common primary *** mean surgical time was 105.3 minutes and mean length of stay was 2.1 d with most patients discharged home(92.5%).There were 18 emergency department(ED)visits within 90 d of surgery resulting in a 90 d ED visit rate of 7.1%,including a 2.4%orthopedic-related ED visit ra

关键词： Total knee arthroplasty Cruciate retaining Kinematic design Survivorship Bearing material Prosthetic design Clinical outcomes Patient-reported outcome measures

Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework

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Defence Technology（防务技术） 2024年第1期31卷 278-287页

作者： Jintao Zhang Xingling Shao Wendong Zhang Zongyu Zuo School of Instrument and Electronics North University of ChinaTaiyuan 030051China State Key Laboratory of Dynamic Measurement Technology North University of ChinaTaiyuan 030051China Seventh Research division School of Automation Science and Electrical EngineeringBeihang UniversityBeijing 100191China

This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular *** addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any *** significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient ***,all variables existing in the entire system are analyzed to be *** and experimental results are provided to validate the utility of suggested solution.

关键词： Multi-circular formation Reinforced transient profiles Nonholonomic vehicles Path following