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Predicting risk of postpartum hemorrhage using machine learning approach:A systematic review

Gynecology and Obstetrics Clinical Medicine 2023年第3期3卷 170-174页

作者： Amene Ranjbar Sepideh Rezaei Ghamsari Banafsheh Boujarzadeh Vahid Mehrnoush Fatemeh Darsareh Fertility and Infertility Research center Hormozgan University of Medical SciencesBandar AbbasIran Department of Midwifery and Reproductive Health Tehran University of Medical SciencesTehranIran Mother and Child Welfare Research center Hormozgan University of Medical SciencesBandar AbbasIran

Background Postpartum hemorrhage(PPH)could be avoided by identifying high-risk *** objective of this systematic review is to determine PPH predictors using machine learning(ML)*** This strategy included searching for studies from inception through November 2022 through the database included:Cochrane Central Register,PubMed,MEDLINE,EMBASE,ProQuest,Scopus,WOS,IEEE Xplore,and the Google Scholar *** search methodology employed the pico framework(population,intervention,control,and outcomes).In this study,“P”represents PPH populations,“I”represents the ML approach as intervention,“C”represents the traditional statistical analysis approach as control,and“O”represents prediction and diagnosis *** quality assessment of each included study was performed using the PROBAST *** The initial search strategy resulted in 2048 citations,which were subsequently refined by removing duplicates and irrelevant ***,four studies were deemed eligible for inclusion in the *** these studies,three were classified as having a low risk of bias,while one was considered to have a low to moderate risk of bias.A total of 549 unique variables were identified as candidate predictors from the included *** distinct models were chosen as ML algorithms from the four *** of the four studies employed different metrics,such as the area under the curve,false positive rate,false negative rate,and sensitivity,to report the accuracy of their *** ML models exhibited varying accuracies,with the area under the curve(AUC)ranging from 0.706 to *** weighted predictors were identified as significant factors in PPH risk *** included pre-pregnancy maternal weight,maternal weight at the time of admission,fetal macrosomia,gestational age,level of hematocrit at the time of admission,shock index,frequency of contractions during labor,white blood cell count,pregnancy-induced hypertension,the weight of

关键词： Postpartum hemorrhage Risk factors Machine learning

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Dissolution-precipitation growth of uniform and clean two dimensional transition metal dichalcogenides

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National Science Review 2021年第3期8卷 108-116页

作者： Zhengyang Cai Yongjue Lai Shilong Zhao Rongjie Zhang Junyang Tan Simin Feng Jingyun Zou Lei Tang Junhao Lin Bilu Liu Hui-Ming Cheng Shenzhen Geim Graphene center Tsinghua-Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate SchoolTsinghua University Shenyang National Laboratory for Materials Sciences Institute of Metal ResearchChinese Academy of Sciences Department of Physics Southern University of Science and Technology

Two dimensional transition metal dichalcogenides(TMDCs) have attracted much interest and shown promise in many ***,it is challenging to obtain uniform TMDCs with clean surfaces,because of the difficulties in controlling the way the reactants are supplied to the reaction in the current chemical vapor deposition growth ***,we report a new growth approach called’dissolution-precipitation’(DP) growth,where the metal sources are sealed inside glass substrates to control their feeding to the ***,the diffusion of metal source inside glass to its surface provides a uniform metal source on the glass surface,and restricts the TMDC growth to only a surface reaction while eliminating unwanted gas-phase *** feature gives rise to highly uniform monolayer TMDCs with a clean surface on centimeter-scale *** DP growth works well for a large variety of TMDCs and their alloys,providing a solid foundation for the controlled growth of clean TMDCs by the fine control of the metal source.

关键词： dissolution-precipitation growth two dimensional materials transition metal dichalcogenides uniform clean

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DISTRIBUTION OF VIRIOPLANKTON IN THE KUROSHIO CURRENT AND THE ADJACENT AREA IN THE EAST CHINA SEA AS DETERMINED BY FLOW CYTOMETRY

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Chinese Journal of Oceanology and Limnology 2002年第S1期20卷 1-7页

作者：杨燕辉焦念志 Ministry of Education Key Laboratory for Marine Environmental Sciences Center of Marine Environmental Science Xiamen University Xiamen 361005 China

Distribution of one group of marine viral particles along the Kuroshio Current and theadjacent area was investigated in June, 1998 using flow cytometry for the first time. The position of thisgroup of virioplankton in flow cytometry plots coincided with the position of the V-I group reported byMarie et al. （1999）. Abundances of this group of virioplankton in the surface water ranged from 3.4×105 to 2. 3×106 ml-1 in the investigated area. High abundance occurred in the shelf water and low abun-

关键词： virioplankton flow cytometry East China Sea

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EFFECTS OF IRON ON picoPLANKTON IN THE SOUTH CHINA SEA AS REVEALED BY SIMULATED IN SITU INCUBATION EXPERIMENT

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Chinese Journal of Oceanology and Limnology 2002年第S1期20卷 66-73页

作者：杨燕辉焦念志 Ministry of Education Key Laboratory for Marine Environmental Sciences Center of Marine Environmental Science Xiamen University Xiamen 361005 China

Iron （FeCl3） enrichment experiment was carried out at 6. 3°N, 110°E in the SouthChina Sea. Cell abundances of the main groups of picoplankton Synechococcus, Prochlorococcus, picoeu-karyote and heterotrophic bacteria were traced during the experiment by flow cytometry （FCM）. Resultsshowed that picoplankton responded rapidly to iron of nano mole concentration. However, high concentra-

关键词： iron enrichment picoplankton South China Sea

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Diversity and community structure of eukaryotic microalgae in surface sediments in the central Bohai Sea,China,based on a metabarcoding approach

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Journal of Oceanology and Limnology 2022年第6期40卷 2277-2291页

作者： Zhaohui WANG Chaofan WANG Maoting WANG Weiguo LI Wencong ZHONG Lei LIU Tao JIANG College of Life Science and Technology Jinan UniversityGuangzhou 510632China Engineering Research center of Tropical and Subtropical Aquatic Ecological Engineering Ministry of EducationGuangzhou 510632China School of Ocean Yantai UniversityYantai 264005China

Sediment samples were collected at 17 stations in the central Bohai Sea,China,and the diversity and community structure of eukaryotic microalgae were assessed by metabarcoding the V4 region of 18S r DNA.A total of 930 operational taxonomic units(OTUs)were detected for microeukaryotes,including 98algal *** algal communities comprised 42 genera belonging to 19 classes of six phyla,and they were dominated by chrysophytes and *** were also the most diverse microalgal *** nano-sized dinoflagellates Biecheleria halophila and Azadinium trinitatum occurred abundantly in the study area;however,they have not been reported previously,as they may be overlooked or misidentified in light *** pico-sized chlorophytes were detected in the sediment *** of the detected OTUs were assigned to potentially harmful and/or bloom-forming microalgae,suggesting some potential risks of harmful algal blooms in the central Bohai *** capacity of metabarcoding to detect morphologically cryptic and small species makes this method a sufficiently sensitive means of detection for assessing eukaryotic microalgae in sediments.

关键词： microalgae dinoflagellate cysts high throughput sequencing marine sediment the Bohai Sea resting stages

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Electron acceleration in interaction of magnetic islands in large temporal-spatial turbulent magnetic reconnection

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Earth and Planetary Physics 2019年第1期3卷 17-25页

作者： BoJing Zhu Hui Yan David A Yuen YaoLin Shi Yunnan Observatories Chinese Academy of Sciences center for Astronomical Mega-Science Chinese Academy of Sciences National Supercomputer center in Guangzhou Sun Yat-sen University Department of Earth Science and Minnesota Supercomputing Institute University of Minnesota Applied Physics and Applied Mathematics Department Columbia University Key Laboratory of Computing Geodynamics Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences

A new combined Fermi, betatron, and turbulent electron acceleration mechanism is proposed in interaction of magnetic islands during turbulent magnetic reconnection evolution in explosive astrophysical phenomena at large temporal-spatial scale(LTSTMR), the ratio of observed current sheets thickness to electron characteristic length, electron Larmor radius for low-β and electron inertial length for high-β, is on the order of 10^(10)–10^(11); the ratio of observed evolution time to electron gyroperiod is on the order of 10~7–10~9).The original combined acceleration model is known to be one of greatest importance in the interaction of magnetic islands; it assumes that the continuous kinetic-dynamic temporal-spatial scale evolution occurs as two separate independent *** this paper, we reconsider the combined acceleration mechanism by introducing a kinetic-dynamic-hydro full-coupled model instead of the original micro-kinetic or macro-dynamic *** investigate different acceleration mechanisms in the vicinity of neutral points in magnetic islands evolution, from the stage of shrink and breakup into smaller islands(kinetic scale), to the stage of coalescence and growth into larger islands(dynamic scale), to the stages of constant and quasi-constant(contracting-expanding) islands(hydro scale).As a result, we give for the first time the acceleration efficiencies of different types of acceleration mechanisms in magnetic islands' interactions in solar atmosphere LTSTMR activities(pico-, 10^(–2)–10~5 m; nano-, 10~5–10~6 m; micro-, 10~6–10~7 m; macro-, 10~7–10~8 m; large-,10~8–10~9 m).

关键词： hybrid particle acceleration mechanism large temporal-spatial turbulent magnetic reconnection Hydro-Dynamic-Kinetic model

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3D dynamic motion of a dielectric micro-sphere within optical tweezers

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Opto-Electronic Advances 2021年第1期4卷 14-24页

作者： Jing Liu Mian Zheng Zhengjun Xiong Zhiyuan Li Institute of Laser and Intelligent Manufacturing Technology South-Central University for NationalitiesWuhan 430074China China Ship Development and Design center Wuhan 430064China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

Known as laser trapping,optical tweezers,with nanometer accuracy and pico-newton precision,plays a pivotal role in single bio-molecule measurements and controllable motions of *** order to advance the flourishing applications for those achievements,it is necessary to make clear the three-dimensional dynamic process of micro-particles stepping into an optical *** this paper,we utilize the ray optics method to calculate the optical force and optical torque of a micro-sphere in optical *** the influence of viscosity force and torque taken into account,we numerically solve and analyze the dynamic process of a dielectric micro-sphere in optical tweezers on the basis of Newton mechanical equations under various conditions of initial positions and velocity vectors of the *** particle trajectory over time can demonstrate whether the particle can be successfully trapped into the optical tweezers center and reveal the subtle details of this trapping *** in a simple pair of optical tweezers,the dielectric micro-sphere exhibits abundant phases of mechanical motions including acceleration,deceleration,and *** studies will be of great help to understand the particle-laser trap interaction in various situations and promote exciting possibilities for exploring novel ways to control the mechanical dynamics of microscale particles.

关键词： optical tweezers 3D dynamic motion ray optics method Newton mechanical equations

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Processes underlying the laser photochromic effect in colloidal plasmonic nanoparticle aggregates

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Chinese Physics B 2020年第3期29卷 412-419页

作者： A E Ershov V S Gerasimov I L Isaev A P Gavrilyuk S V Karpov Institute of Computational Modeling SB RAS 660036KrasnoyarskRussia Siberian Federal University Krasnoyarsk660041Russia Kirensky Institute of Physics Federal Research Center KSC SB RAS660036KrasnoyarskRussia Siberian State University of Science and Technology Krasnoyarsk 660014Russia

We have studied the dynamic and static processes occurring in disordered multiparticle colloidal Ag aggregates with natural structure and affecting their plasmonic absorption spectra under pico-and nanosecond pulsed laser radiations, as well as the physical origin responsible for these processes. We have shown that depending on the duration of the laser pulse,the mechanisms of laser modification of such aggregates can be associated both with changes in the resonant properties of the particles due to their heating and melting(picosecond irradiation mode) and with the particle shifts in the resonant domains of the aggregates(nanosecond pulses) which depend on the wavelength, intensity, and polarization of the *** mechanisms result in formation of a narrow dip in the plasmonic absorption spectrum of the aggregates near the laser radiation wavelength and affect the shape and position of the dip. The effect of polydispersity of nanoparticle aggregates on laser photochromic reaction has been studied.

关键词： nanoparticle surface plasmon resonance photochromic process pulsed laser radiation

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The spatial and temporal distribution of microalgae in the South China Sea:evidence from GIS-based analysis of 18S rDNA sequences

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Science China(Life Sciences) 2008年第12期51卷 1121-1128页

作者： LI LüYan1, HUANG QiaoJuan1, WU ShuHui1, LIN Duan2, CHEN JiaHui2 & CHEN YueQin1 1 Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, Sun Yat-Sen University, Guangzhou 510275, China 2 South China Sea Environmental Monitoring center, State Oceanic Administration, Guangzhou 510300,China Key Laboratory of Gene Engineering of the Ministry of Education State Key Laboratory for Biocontrol Sun Yat-Sen University Guangzhou China South China Sea Environmental Monitoring center State Oceanic Administration Guangzhou China

The purpose of this study was to estimate the spatial and temporal variation of microalgae in the South China Sea and to demonstrate the environmental factors controlling the diversity of microalgae by GIS (geographic information system)-based analysis of 18S rDNA sequences. Six 18S rDNA libraries were constructed from environmental samples collected at different sites in the study area, and more than 600 18S rDNA sequences were determined. The rDNA sequence data were then analyzed by DIVA-GIS software to display the spatial and temporal variation of phytoplankton’s composition. It was shown that the autotrophic eukaryotic plankton dominated over the heterotrophic cells in most of our clone libraries, and the dominating phytoplankton was Dinophyceae except for Bacillariophyta at the Xiamen harbor. The percentages of these two groups were controlled by water temperature and salinity. Our results also revealed that the species composition of Chlorophyta showed a close relationship with latitude, changing from Prasinophyceae at the high latitude to Trebouxiophyceae at the low latitude. Several newly classified picoplankton lineages were first uncovered in the South China Sea, including the pico-sized green alga Ostreococcus sp. and picochlorum eukaryotum, and picobiliphytes, which was just discovered in 2007 with unknown affinities to other eukaryotes. Their spatial and temporal variation were also analyzed and discussed.

关键词： microalgae GIS-based analysis 18S rDNA South China Sea

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The Energy Transfer Processes between Carotenoid and Chlorophyll Regulated by Electron Exchange Mechanism

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Chinese Chemical Letters 2001年第11期12卷 983-986页

作者： Ye LI Jing Quan ZHAO Li Jin JIANG Zhao Yong SUN Xi Cheng AI Xing Kang ZHANG The center for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080 State Key laboratory for Structure Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100080 Institute of Photographic Chemistry Beijing 100101

The energy transfer efficiency between carotenoids and chlorophyll depend on temperature and viscosity of the media. A 3.5 ps process was detected by the pico-second time-resolved spectra and the process was proved to... 详细信息

关键词： carotenoid chlorophyll phycobilisomes fluorescence

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