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Optical frequency comb technology: from ground to space

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Astronomical Techniques and Instruments 2024年第2期1卷 105-116页

作者： Xiaodong shao Yu yan Hainian Han Zhiyi Wei Beijing National Laboratory of Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

Optical frequency combs,as powerful tools for precision spectroscopy and research into optical frequency standards,have driven continuous progress and significant breakthroughs in applications such as time-frequency transfer,measurement of fundamental physical constants,and high-precision ranging,achieving a series of milestone results in ground-based *** the continuous maturation and evolution of femtosecond lasers and related technologies,optical frequency combs are moving from ground-based applications to astronomical and space-based applications,playing an increasingly important role in atomic clocks,exoplanet observations,gravitational wave measurements,and other *** paper,focusing on astronomical and space-based applications,reviews research progress on astronomical frequency combs,optical clock time-frequency networks,gravitational waves,dark matter measurement,dual-comb large-scale absolute ranging,and high-resolution atmospheric *** enhanced performance and their gradual application in the field of space-based research,optical frequency combs will undoubtedly provide more powerful support for astronomical science and cosmic exploration in the future.

关键词： Optical frequency comb Astronomical comb Optical clock-based time and frequency network Gravitational waves and dark matter Dual-comb ranging

Staging liver fibrosis with various diffusion-weighted magnetic resonance imaging models

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World Journal of Gastroenterology 2024年第9期30卷 1164-1176页

作者： yan-Li Jiang Juan Li Peng-Fei Zhang Feng-Xian Fan Jie Zou Pin yang Peng-Fei Wang shao-Yu Wang Jing Zhang Department of Magnetic Resonance Imaging The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina Second Clinical School Lanzhou UniversityLanzhou 730030Gansu ProvinceChina Gansu Province Clinical Research Center for Functional and Molecular Imaging The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina Department of Hepatology The Second Hospital&Clinical Medical SchoolLanzhou UniversityLanzhou 730030Gansu ProvinceChina MR Scientific Marketing Siemens HealthineersXi’an 710065Shaanxi ProvinceChina

BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver ***,its diagnostic performance is inconsistent among ***,it is worth studying the diagnostic value of various diffusion models for liver fibrosis in one *** To evaluate the clinical potential of six diffusion-weighted models in liver fibrosis staging and compare their diagnostic *** This prospective study enrolled 59 patients suspected of liver disease and scheduled for liver biopsy and 17 healthy *** participants underwent multi-b value *** main DWI-derived parameters included Mono-apparent diffusion coefficient(ADC)from mono-exponential DWI,intravoxel incoherent motion model-derived true diffusion coefficient(IVIM-D),diffusion kurtosis imaging-derived apparent diffusivity(DKI-MD),stretched exponential model-derived distributed diffusion coefficient(SEM-DDC),fractional order calculus(FROC)model-derived diffusion coefficient(FROC-D)and FROC model-derived microstructural quantity(FROC-μ),and continuous-time random-walk(CTRW)model-derived anomalous diffusion coefficient(CTRW-D)and CTRW model-derived temporal diffusion heterogeneity index(CTRW-α).The correlations between DWI-derived parameters and fibrosis stages and the parameters’diagnostic efficacy in detecting significant fibrosis(SF)were assessed and *** CTRW-D(r=-0.356),CTRW-α(r=-0.297),DKI-MD(r=-0.297),FROC-D(r=-0.350),FROC-μ(r=-0.321),IVIM-D(r=-0.251),Mono-ADC(r=-0.362),and SEM-DDC(r=-0.263)were significantly correlated with fibrosis *** areas under the ROC curves(AUCs)of the combined index of the six models for distinguishing SF(0.697-0.747)were higher than each of the parameters alone(0.524-0.719).The DWI models’ability to detect SF was *** combined index of CTRW model parameters had the highest AUC(0.747).CONCLUSION The DWI models were similarly valuable in distinguishing SF in patients with liver *** combined index of CTRW paramet

关键词： Liver fibrosis Magnetic resonance imaging Diffusion-weighted magnetic resonance Liver biopsy Significant fibrosis

PE-Cd复合污染土壤中Cd释放迁移特征及机制

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环境科学 2024年第2期45卷 1069-1079页

作者：王迪徐绍辉邵明艳林青青岛大学环境科学与工程学院青岛266071 青岛地质工程勘察院(青岛地质勘查开发局) 青岛266101

微塑料广泛分布于土壤环境中,不仅改变了土壤的理化性质还可富集重金属等污染物,进而影响它们在环境中的归趋.目前,有关微塑料对土壤中重金属运移影响的作用机制尚不清晰.选取聚乙烯(PE)微塑料和Cd为研究对象,在明确PE对Cd^(2+)吸附作... 详细信息

微塑料广泛分布于土壤环境中,不仅改变了土壤的理化性质还可富集重金属等污染物,进而影响它们在环境中的归趋.目前,有关微塑料对土壤中重金属运移影响的作用机制尚不清晰.选取聚乙烯(PE)微塑料和Cd为研究对象,在明确PE对Cd^(2+)吸附作用机制的基础上,通过土柱淋溶实验研究了不同离子强度和类型(Ca^(2+)、Na^(+))下,PE含量和粒径对土壤中Cd释放迁移行为的影响.结果表明,PE对Cd^(2+)的吸附能力随粒径的增大而降低,以物理吸附为主,受颗粒内扩散过程控制.PE对Cd释放迁移的影响与CaCl_(2)浓度有关,高离子强度下(0.05 mol·L^(-1)和0.1 mol·L^(-1)),PE促进了Cd^(2+)的迁移,Cd^(2+)的出流浓度分别由6.48 mg·L^(-1)和16.79 mg·L^(-1)升高到7.12 mg·L^(-1)和23.45 mg·L^(-1);低离子强度下(0.01 mol·L^(-1))抑制了Cd的迁移,Cd^(2+)的出流浓度由0.66 mg·L^(-1)降低至0.57 mg·L^(-1);且PE添加量越大,促进或抑制作用越显著.同时,Cd的释放迁移也受PE粒径和含量的影响,当添加量较小(1%、4%)时,大粒径对Cd^(2+)迁移的促进效果更加显著;而当添加量较大(7%和20%)时,小粒径更易促进Cd^(2+)的迁移.当淋溶液为NaCl时,土壤的渗透性显著降低,PE对Cd的迁移无显著影响,但改变了土壤团聚体的稳定性.总之,微塑料改变了土壤中Cd的释放迁移行为,作用结果不仅与微塑料的粒径和含量有关,还受土壤溶液化学性质的影响.

关键词：聚乙烯(PE) 微塑料吸附镉(Cd) 淋溶迁移土壤

A novel predictor of unsustained return of spontaneous circulation in cardiac arrest patients through a combination of capnography and pulse oximetry: a multicenter observational study

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World Journal of Emergency Medicine 2024年第1期15卷 16-22页

作者： Jing yang Hanqi Tang Shihuan shao Feng Xu yangyang Fu Shengyong Xu Chen Li yan Li yang Liu Joseph Harold Walline Huadong Zhu Yuguo Chen Xuezhong Yu Jun Xu Emergency Department State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China Emergency Department Peking University People’s HospitalBeijing 100044China Department of Emergency and Chest Pain Center Shandong Provincial Clinical Research Center for Emergency and Critical Care MedicineKey Laboratory of Emergency and Critical Care Medicine of Shandong ProvinceQilu Hospital of Shandong UniversityJinan 250012China Emergency Department Beijing Jishuitan HospitalBeijing 100035China Emergency Department Tianjin Medical University General HospitalTianjin 300052China Department of Emergency Medicine Penn State Health Milton S.Hershey Medical Center and Penn State College of MedicineHershey 17033USA

BACKGROUND:Unsustained return of spontaneous circulation(ROSC)is a critical barrier to survival in cardiac arrest *** study examined whether end-tidal carbon dioxide(ETCO_(2))and pulse oximetry photoplethysmogram(POP)parameters can be used to identify unsustained ***:We conducted a multicenter observational prospective cohort study of consecutive patients with cardiac arrest from 2013 to ***’general information,ETCO_(2),and POP parameters were collected and statistically ***:The included 105 ROSC episodes(from 80 cardiac arrest patients)comprised 51 sustained ROSC episodes and 54 unsustained ROSC *** 24-hour survival rate was significantly higher in the sustained ROSC group than in the unsustained ROSC group(29.2%vs.9.4%,P<0.05).The logistic regression analysis showed that the difference between after and before ROSC in ETCO_(2)(ΔETCO_(2))and the difference between after and before ROCS in area under the curve of POP(ΔAUCp)were independently associated with sustained ROSC(odds ratio[OR]=0.931,95%confi dence interval[95%CI]0.881-0.984,P=0.011 and OR=0.998,95%CI 0.997-0.999,P<0.001).The area under the receiver operating characteristic curve ofΔETCO_(2),ΔAUCp,and the combination of both to predict unsustained ROSC were 0.752(95%CI 0.660-0.844),0.883(95%CI 0.818-0.948),and 0.902(95%CI 0.842-0.962),***:Patients with unsustained ROSC have a poor *** combination ofΔETCO_(2) andΔAUCp showed signifi cant predictive value for unsustained ROSC.

关键词： Return of spontaneous circulation Pulse oximetry photoplethysmogram End-tidal carbon dioxide Cardiac arrest Cardiopulmonary resuscitation

Efficacy and Safety of Bufei Jiedu Granules in Treating Multidrug-Resistant Pulmonary Tuberculosis:A Multi-center,Double-Blinded and Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2024年第7期30卷 579-587页

作者： ZHANG shao-yan QIU Lei ZHANG Shun-xian XIAO He-ping CHU Nai-hui ZHANG Xia ZHANG Hui-qiang ZHENG Pei-yong ZHANG Hui-yong LU Zhen-hui Institute of Respiratory Diseases Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai200032China Clinical Research Center Shanghai University of Traditional Chinese MedicineShanghai200032China Department of Tuberculosis Shanghai Pulmonary HospitalTongji UniversityShanghai200433China Department of Tuberculosis Beijing Chest HospitalCapital Medical UniversityBeijing101100China Department of Tuberculosis the Second Hospital of NanjingNanjing210003China Department of Tuberculosis the First Hospital Affiliated to Xinxiang Medical CollegeXinxiangHenan Province453100China

Objective: To assess the efficacy and safety of Bufei Jiedu(BFJD) Granules as adjuvant therapy for patients with multidrug-resistant pulmonary tuberculosis(MDR-PTB). Methods: A large-scale, multi-center, double-blinded, and randomized controlled trial was conducted in 18 sentinel hospitals in China from December 2012 to December 2016. A total of 312 MDR-PTB patients were randomly assigned to BFJD Granules or placebo groups(1:1) using a stratified randomization method, which both received the long-course chemotherapy regimen for 18 months(6 Am-Lfx-P-Z-Pto, 12 Lfx-P-Z-Pto). Meanwhile, patients in both groups also received BFJD Granules or placebo twice a day for a total of 18 months, respectively. The primary outcome was cure rate. The secondary outcomes included time to sputum-culture conversion, changes in lung cavities and quality of life(QoL) of patients. Adverse reactions were monitored during and after the trial. Results: A total of 216 cases completed the trial, 111 in the BFJD Granules group and 105 in the placebo group. BFJD Granules, as adjuvant treatment, increased the cure rate by 13.6% at the end of treatment, compared with the placebo(58.4% vs. 44.8%, P=0.02), and accelerated the median time to sputum-culture conversion(5 months vs. 11 months). The cavity closure rate of the BFJD Granules group(50.6%, 43/85) was higher than that of the placebo group(32.1%, 26/81;P=0.02) in patients who completed the treatment. At the end of the intensive treatment, according to the 36-item Short Form, the BFJD Granules significantly improved physical functioning, general health, and vitality of patients relative to the placebo group(all P<0.01). Overall, the death rates in the two groups were not significantly different;5.1%(8/156) in the BFJD Granules group and 2.6%(4/156) in the placebo group. Conclusions: Supplementing BFJD Granules with the long-course chemotherapy regimen significantly increased the cure rate and cavity closure rate, and rapidly improved QoL of pati

关键词： alternative medicine Chinese herbal formula Bufei Jiedu Granules multidrug-resistant tuberculosis long-course chemotherapy regimen randomized controlled trial

Changes of the trace metals in ice core during 1915-2016 in coastal eastern Antarctica

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Advances in Climate Change Research 2024年第4期15卷 596-608页

作者： Jing-Wen LIU Chuan-Jin LI Gui-Tao SHI yan LIU Zhi-Heng DU Ming-Hu DING shao-Peng GAO Cun-De XIAO Shi-Chang KANG Bo SUN State Key Laboratory of the Cryosphere Science Northwest Institute of the Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Polar Science of State Oceanic Administration Polar Research Institute of ChinaShanghai 200136China Key Laboratory of Geographic Information Science(Ministry of Education) School of Geographic Sciences and Institute of Eco-ChongmingEast China Normal UniversityShanghai 200241China Institute of Tibetan Plateau and Polar Regions Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Instituie of the Tibetan PlateauChinese Academy of SciencesBeijing 100101China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

Antarctic trace metal records provide important information for grasping the influence of human activities on the environment over the last *** CA2016-75 ice core is located along the East Antarctic Zhongshan Station-Dome A,enhances the record of metals research in the East Antarctic region,and its high-resolution supplies data support for the study of high-frequency climatic drivers and the effect of human activities on the Antarctic environment.A thorough dataset on seven trace metals(Al,Fe,Mn,Cu,Zn,Ba and Pb)in a coastal ice core in eastern Antarctica during the previous 102 years(1915-2016)is presented in this *** has the lowest concentration(9.51±20.95 pg g^(-1)),and Ba has the highest concentration(36.57±51.35 ng g^(-1)).Notable variations are observed between the pre-1968 AD and post-1968 AD phases for Mn,Zn and *** abrupt,remarkable increase in the concentrations coincided with the change of metal smelting production in the southern *** addition to this,it may also be related to local Antarctic scientific research *** and Fe,the primary crustal elements,are essentially obtained from soil dust;Cu shows high crustal enrichment factors(EFc,>10),indicating that it is notably affected by anthropogenic ***,the anthropogenic activities in the Southern Hemisphere have had an impact on lead deposition in *** study not only enriches the trace metal historical record along the Zhongshan Station-Dome A but also provides a high-resolution ice core record,which is very crucial for the reconstruction of trace metal concentration changes in the last 100 years.

关键词： Eastern Antarctica Ice core Trace metals Human activities

Enhanced photothermal dehydration of methanol over W_(18)O_(49)/Au/SAPO-34 catalysts with broadened light absorption

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Rare Metals 2024年第3期43卷 1139-1152页

作者： Ya-Qin Tang Meng-Xia yan Chang-Qian Lu shao-Yuan Li Kui-Xian Wei Tao Qu Wen-HuiMa Yong-Nian Dai Kong-Zhai Li Da-Jun Luo Xue-Liang Zhang Yi-Ke Liu Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China School of Materials and Energy Engineering Guizhou Institute of TechnologyGuiyang550003China

Methanol-to-olefins(MTO)process is one of the most critical pathways to produce low carbon ***,the reaction is driven by thermal catalysis,which inevitably needs to consume large amounts of fossil *** a new technique to substitute for the fuel burning is urgent for MTO process to improve the industry prospects and ***,we report a novel W_(18)O_(49)/Au/SAPO-34(W/Au/S),a multifunctional photothermal catalyst for the MTO reaction.A high methanol conversion was achieved under xenonum(Xe)lamp irradiation,yielding methyl ether(ME)and ethylene as the main *** optimized W/Au/S catalysts showed ethylene yield as high as 250μmol in 60 min,which was 2.5 times higher than that of Au/*** physiochemical characterization revealed that the SAPO-34 molecular sieves were surrounded by Au and W_(18)O_(49)nanoparticles,which exhibited a strong localized surface plasmon resonance excitation around 540 nm and light absorption beyond 500 *** multifunctional catalysts showed a strong photothermal effect,arising from the broadened light absorption of Au and W_(18)O_(49)nanoparticles,leading to a temperature as high as 250℃on the surface of the *** study showed that the superior ethylene selectivity of W/Au/S catalysts was attributed to the moderating acidic sites of W_(18)O_(49)for methanol dehydration to *** research may provide new insight for designing heterostructures to improve photo-to-chemical conversion performance and is expected to accelerate progress toward the excellent multifunctional photothermal catalysts with broad light absorption for methanol activation and C-C bond formation.

关键词： Methanol conversion Ethylene Photothermal catalysis W_(18)O_(49) BrΦnsted-acid

基于特征选择和iJaya-SVR的年度电力消费预测研究

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控制与决策 2024年第3期39卷 1039-1047页

作者：高锋邵雪焱北京大学工学院北京100871 中国科学院科技战略咨询研究院北京100190

准确的电力消费预测对能源规划和政策制定具有重要意义.鉴于已有研究忽略了特征冗余以及智能优化算法控制参数不确定对预测精度的影响,引入最大相关最小冗余(MRMR)算法筛选电力消费的关键影响因素作为预测指标,提出改进的Jaya算法(iJaya... 详细信息

准确的电力消费预测对能源规划和政策制定具有重要意义.鉴于已有研究忽略了特征冗余以及智能优化算法控制参数不确定对预测精度的影响,引入最大相关最小冗余(MRMR)算法筛选电力消费的关键影响因素作为预测指标,提出改进的Jaya算法(iJaya)用于优化支持向量回归(SVR)的超参数,进而构建MRMR-iJaya-SVR预测模型.以我国的年度电力消费数据为例,对MRMR-iJaya-SVR模型的预测效果进行验证,并利用北京市的年度电力消费数据测试其鲁棒性.结果表明:iJaya算法具有较强的全局搜索能力和较好的稳定性, MRMR-iJayaSVR模型在单步预测和多步预测中的表现均优于基准模型.此外,对于不同的数据集, MRMR-iJaya-SVR模型均具有良好的鲁棒性.

关键词：特征选择改进的Jaya算法最大相关最小冗余支持向量回归混合预测模型电力消费预测

Switching On/Off of Guide RNA by Photoinduced Strand Displacement for Functional Control of CRISPR/Cas9

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CCS Chemistry 2024年第5期6卷 1338-1351页

作者： yang Wang Chao-Qun Wu Qiu-Long Zhang Ming shao yan Liu Liang-Liang Wang Zun-Yun Wang Juan Du Liang Xu Central Laboratory Department of the Second Affiliated Hospital School of MedicineThe Chinese University of Hong KongShenzhen&Longgang District People’s Hospital of ShenzhenShenzhen 518172 Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging National-Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringShenzhen University Medical SchoolShenzhen 518060 MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275 School of Pharmacy and Medical Technology Putian UniversityPutian 351100

Functional control of CRISPR/Cas9 is essential for precise gene *** engineering of guide RNA(gRNA)provides diverse approaches for conditional control of CRISPR/Cas9 function with a variety of chemical reactive ***,previous investigations into chemically engineering gRNA only unidirectionally regulated the CRISPR/Cas9 function via stimuli-induced caging/decaging ***,we propose a combinatory strategy to engineer the dynamics of gRNA in which photocontrolled strand-displacement reactions coupled with sequence designs of gRNA can achieve lightinduced switching-on/off control of CRISPR/Cas9 *** analysis and cellular gene regulation indicate this approach is capable of both activating and deactivating CRISPR/Cas9 activities using light ***,photocontrolled multiplex modulations of gene expression for opposite regulatory effects have also been achieved simultaneously under the same cellular *** work establishes an essential principle for construction of stimuli-induced switching-on/off modulations of gRNA that can greatly enrich the versatility of conditional control for a variety of CRISPR/Cas9-based applications.

关键词： modified oligonucleotides gene manipulation optical control CRISPR/Cas9 strand displacement