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Magnetic field imaging with radio-frequency optically pumped magnetometers [Invited]

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Chinese Optics Letters 2024年第6期22卷 38-45页

作者： Xiyu Liu Junlong han Wei xiao Teng Wu Xiang Peng {2. Guo School of Electronics Peking UniversityBeijing 100871China

High-sensitivity radio-frequency optically pumped magnetometers (RF-OPMs), working without cryogenic condition, play a critical role in magnetic field imaging(MFI) at low frequencies(e.g., 100 Hz to 1 MHz). We introduce the principle of operation and recent developments of RF-OPMs and focus on reviewing the MFI applications in magnetic induction tomography, ultralow-field magnetic resonance imaging, and magnetic particle imaging. For the applications of RF-OPMs, ranging from industrial monitoring to medical imaging and security screening, the unshielded and portable RF-OPMs(and RF-OPM array)techniques are still under the further development for detecting and scanning over the target object for accomplishing the final three-dimensional imaging, and thus extremely require the abilities of active compensation of the ambient magnetic field and sensor miniaturization in the future.

关键词： magnetic field imaging radio frequency optically pumped magnetometer

Ionization state of cosmic hydrogen by early stars and quasars

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Research in Astronomy and Astrophysics 2009年第6期9卷 665-681页

作者： xiao-Chun Mao1,2.1 National Astronomical Observatories, Chinese academy of {2., beijing 100012. china 2.graduate university of Chinese academy of {2., beijing 1.0049, china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate university of Chinese {2. of sciences Beijing 100049 China

Cosmic hydrogen is reionized and maintained in its highly ionized state by the ultraviolet emission attributed to an early generation of stars and quasars. The Lyα opacity observed in absorption spectra of high-redshift quasars permits more stringent constraints on the ionization state of cosmic hydrogen. Based on density perturbation and structure formation theory, we develop an analytic model to trace the evolution of the ionization state in the post-overlap epoch of reionization, in which the bias factor is taken into account. For quasars, we represent an improved luminosity function by utilizing a hybrid approach for the halo formation rate that is in reasonable agreement with the published measurements at 2.≤ z ≤ 6. Comparison with the classic Press-Schechter mass function of dark matter halos, we demonstrate that the biased mass distribution indeed enhances star formation efficiency in the overdense environment by more than 2. per cent following the overlap of ionized bubbles. In addition, an alternative way is introduced to derive robust estimates of the mean free path for ionizing photons. In our model, star-forming galaxies are likely to dominate the ionizing background radiation beyond z = 3, and quasars contribute equally above a redshift of z ～ 2.5. From 5 ≤ z ≤ 6, the lack of evolution in photoionization rate can thus be explained by the relatively flat evolution in star formation efficiency, although the mean free path of ionizing photons increases rapidly. Moreover, in the redshift interval z ～ 2.- 6, the expected mean free path and Gunn-Peterson optical depth obviously evolve by a factor of ～ 500 and ～50 respectively. We find that the relative values of critical overdensities for hydrogen ionization and collapse could be 430% at z ≈2.and 2. at z ≈6, suggesting a rapid overlap process in the overdense regions around instant quasars following reionization. We further illustrate that the absolute estimates of the fraction of neutral hydrogen computed fr

关键词： cosmology theory -- formation galaxies -- quasars general -- diffuse radiation -- intergalactic medium

The acceptance of traditional Chinese medicine among patients with Parkinson's disease:A hospital survey

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Journal of Integrative Medicine 2024年第2期22卷 180-187页

作者： Peng Wang Jing hong Zhu-qian Tang Bi-zhen Gong xiao-rong Qi {2. Jiang Bo Pan Qi Chen Postgraduate School Medical School of Chinese People’s Liberation ArmyBeijing 100853China Senior Department of Traditional Chinese Medicine the Sixth Medical Center of PLA General HospitalBeijing 100853China Department of Integration of Chinese and Western Medicine School of Basic Medical SciencesPeking UniversityBeijing 100191China Department of Integrative Oncology the First Affiliated Hospital of Naval Medical UniversityShanghai 200433China School of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China School of Pharmacy Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina Department of Dermatology the First Clinical Medical CollegeAnhui University of Chinese MedicineHefei 230012Anhui ProvinceChina

Objective:The efficacy of medications for Parkinson’s disease(PD)tend to decline over time,which has a serious impact on patients’health and quality of *** some extent,traditional Chinese medicine(TCM)can resolve the distressing problem of ineffective dopaminergic medication in PD *** purpose of this study was to investigate the attitude,acceptance,and independent predictors of TCM in PD patients admitted to the outpatient department of a tertiary ***:A cross-sectional study of PD patients was conducted in the outpatient department of a large tertiary hospital in beijing from March 2.2. to June 2.2..A self-report questionnaire was developed to investigate PD patients’attitudes and acceptance of TCM based on the *** logistic regression analyses were also performed to further clarify the independent predictors influencing patients’adoption of TCM ***:A total of 397 patients completed the questionnaire,of which 78.09%were willing to be treated with TCM and 2..91%indicated that they were not willing to use *** logistic regression analysis showed that several parameters were correlated with a patient’s willingness to include TCM in their therapeutic *** included education level of a bachelor’s degree(odds ratio[OR)=8.554;95%confidence interval[CI]:4.112.17.794;P2.;95%CI:4.577–14.060;P2.;95%CI:3.078–8.537;P2.5.134;P2.10.047;P=0.006,vs not understood),and being willing to discuss ongoing TCM therapy with an attending physician(OR=62.468;95%CI:30.350–12..574;P<0.001,vs not informed).Conclusion:This study initially investigated the acceptance

关键词： Parkinson's disease Traditional Chinese medicine Cross-sectional study

Observation results of relativistic electrons detected by Fengyun-1 satellite and analysis of relativistic electron enhancement (REE) events

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Science china(Physics,Mechanics & Astronomy) 2008年第12期51卷 1947-1956页

作者： YANG xiaoChao1,2. & WANG ShiJin1 1 Center for Space Science and Applied Research, Chinese academy of {2., beijing 100190, china 2.graduate university of Chinese academy of {2., beijing 1.0049, china 1. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China 2. graduate university of Chinese {2. of sciences Beijing 100049 China

The space particle component detector on Fengyun-1 satellite which works at the sun-synchronous orbit of about 870 km altitude has detected relativistic electrons for a long time. In comparison with the SAMPEX satellite observations during 1999–2.04, the relativistic electron data from Fengyun-1 satellite from June 1999 to 2.05 are used to analyze the relativistic electron enhancement (REE) events at the low earth orbit, and the possible correlation among REE events at the low earth orbit, high-speed solar wind and geomagnetic storms is discussed. The statistical result presents that 45 REE events are found in total during this time period, and the strong REE events with the maximum daily average flux > 400 cm?2.srt-1·s?1 occur mostly during the transition period from solar maximum to solar minimum. Among these 45 REE events, four strong REE events last a longer time period from 2.-to 51-day and correlate closely with high speed solar wind and strong geomagnetic storms. Meanwhile, several strong geomagnetic storms occur continuously before these REE events, and these continuous geomagnetic storms would be an important factor causing these long-lasting strong REE events. The correlation analysis for overall 45 events indicates that the strength of the REE events correlates with the solar wind speed and the strength of the geomagnetic storm, and the correlation for strong REE events is much stronger than that for weak REE events.

关键词： relativistic electron enhancement low earth orbit high-speed solar wind geomagnetic storm

Nonlinear interactions between gravity waves and background winds

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Progress in Natural Science:Materials International 2007年第6期17卷 639-644页

作者： Liu xiao1,2.and Xu Jiyao1(1. State Key Laboratory for Space Weather, Center for Space Science and Applied Research, Chinese academy of {2., beijing 100080, china 2. graduate university of Chinese academy of {2., beijing 100039, china) [a]State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China [b]graduate university of Chinese {2. of sciences Beijing China

Using the nonlinear propagating gravity waves (GW) model in the two-dimensional compressible atmosphere and the linear GW theory, the process of GW propagation in different background winds, e.g. the direction of the background wind is opposite to (dead wind) or the same as (tail wind) the direction of the horizontal phase velocity of GW, is studied. The results show that the dead wind prolongs the vertical wavelength and accelerates GW propagation. Therefore, GW propagates up to a higher height becomes instable in a short time and eventually induces an inverse jet flow. Then, the vertical wavelength is becoming short due to the nonlinear interactions between GW and the inverse jet flow. The vertical wavelength and group velocity decrease after GW propagates into the tail wind. The initial instable time is delayed. Although most of GW is trapped in the instable region, some of GW propagates above the instable region. Compared with GW propagation in the tail wind, the nonlinear interactions between GW and the dead wind are also strong. In contrast, the linear GW theory predicts that GW can propagate freely in the dead wind. The vertical wavelength simulated by the nonlinear numerical model is different from that predicted by the linear theory greatly after GW propagates into the dead wind.

关键词： gravity waves background winds vertical group velocity vertical wavelength nonlinear interactions.

The deep thermal characteristic of continental margin of the northern South china Sea

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Chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZhanG Jian & WANG Jiyang1. graduate School, {2. of Science and Technology of china, Chinese academy of sciences, beijing 100039, china 2. Institute of Geology, Chinese academy of sciences, beijing 10002., china graduate School University of Science and Technology of China Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower t{2. 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.

Research on the method for retrieving soil moisture using thermal inertia model

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Science china Earth sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2.1. Information College, South china Agricultural university, Guangzhou 510642. china 2. graduate university of Chinese academy of sciences, beijing 1.0049, china 1. Information College South China Agricultural University Guangzhou 510642 China 2. graduate university of Chinese {2. of sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

METTL7A-mediated m6A modification of corin reverses bisphosphonates-impaired osteogenic differentiation of orofacial BMSCs

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International Journal of Oral Science 2024年第3期16卷 528-538页

作者： Yizhou Jin xiao han Yuejun Wang Zhipeng Fan beijing Key Laboratory of Tooth Regeneration and Function Reconstruction Beijing Stomatological HospitalSchool of StomatologyCapital Medical UniversityBeijingChina beijing Laboratory of Oral Health Capital Medical UniversityBeijingChina Research Unit of Tooth Development and Regeneration Chinese Academy of Medical SciencesBeijingChina

Bisphosphonate-related osteonecrosis of jaw(BRONJ)is characterized by impaired osteogenic differentiation of orofacial bone marrow stromal cells(BMSCs).Corin has recently been demonstrated to act as a key regulator in bone development and orthopedic ***,the role of corin in BRONJ-related BMSCs dysfunction remains unclarified.A m6A epitranscriptomic microarray study from our group shows that the CORIN gene is significantly upregulated and m6A hypermethylated during orofacial BMSCs osteogenic *** knockdown inhibits BMSCs osteogenic differentiation,whereas corin overexpression or soluble corin(sCorin)exerts a promotion ***,corin expression is negatively regulated by bisphosphonates(BPs).Corin overexpression or sCorin reverses BPs-impaired BMSCs differentiation ***,we find altered expression of phos-ERK in corin knockdown/overexpression BMSCs and BMSCs under sCorin ***98059(a selective ERK inhibitor)blocks the corin-mediated promotion *** regard to the high methylation level of corin during osteogenic differentiation,we apply a non-selective m6A methylase inhibitor,Cycloleucine,which also blocks the corin-mediated promotion ***,we demonstrate that METTL7A modulates corin m6A modification and reverses BPs-impaired BMSCs function,indicating that METTL7A regulates corin expression and thus contributes to orofacial BMSCs differentiation *** conclude,our study reveals that corin reverses BPs-induced BMSCs dysfunction,and METTL7A-mediated corin m6A modification underlies corin promotion of osteogenic differentiation via the ERK *** hope this brings new insights into future clinical treatments for BRONJ.

关键词： impaired cor mediated

Organic Integration of Traditional Chinese and Western Medicines—Future of Clinical Practice Guidelines of Integrated Traditional Chinese and Western Medicines

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Chinese Journal of Integrative Medicine 2024年第4期30卷 359-365页

作者： XIE Ying-lan han Fei JIN Ying-hui DING Yan-bing GUO Jing JI Dong-xiao ZhanG Teng CHENxiao-min ShanG hong-cai Department of Traditional Chinese Medicine Encephalopathy Hubei Provincial Hospital of Traditional Chinese MedicineWuhan(430074)China Department of Traditional Chinese Medicine Encephalopathy Hubei Province Traditional Chinese Medicine Research InstituteWuhan(430074)China Xuanwu Hospital of Traditional Chinese Medicine Beijing(100000)China Center for Evidence-Based and Translational Medicine Zhongnan Hospital of Wuhan UniversityWuhan(430074)China College of Acupuncture and Massage College of Health and RehabilitationNanjing University of Chinese MedicineNanjing(210023)China Department of Ophthalmology Huaihe Hospital of Henan UniversityKaifengHenan Province(475000)China Ministry of Education and beijing Key Laboratory of Internal Medicine of Traditional Chinese Medicine Dongzhimen Hospital of Beijing University of Traditional Chinese Medicine/Ministry of Education and Beijing Key Laboratory of Internal Medicine of Traditional Chinese MedicineBeijing(100700)China

The transformation and implementation of clinical practice guidelines for integrated traditional Chinese medicine(TCM)and Western medicine(WM)is crucial to the adoption of medical science and technological findings and is an important way for TCM to be made available to the ***,clinical practice guidelines(CPGs)of TCM and WM integration in recent years was analyzed to clarify the current situation and problems in the existing guidelines according to the following four perspectives:(1)perspective of TCM and WM integration in guidelines,(2.diagnosis Using integrated TCM and WM,(3)integration of TCM and WM treatment,(4)promoting TCM and WM ***,the information and quality evaluation of CPGs for integrated Chinese and Western medicine in 2.2.–2.2. were analyzed to explore the degree and methods of integration of Chinese and Western medicine *** last this study aimed to lay a foundation for the further establishment of Chinese characteristic,repeatable,and calculable clinical practice guidelines of TCM and WM integration.

关键词： clinical practice guidelines integrated traditional Chinese and Western medicine organic integration