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The 3-billion fossil question:How to automate classification of microfossils
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作者 Iver Martinsen David Wade +1 位作者 Benjamin Ricaud Fred Godtliebsen 《Artificial Intelligence in Geosciences》 2024年第1期137-145,共9页
Microfossil classification is an important discipline in subsurface exploration,for both oil&gas and Carbon Capture and Storage(CCS).The abundance and distribution of species found in sedimentary rocks provide val... Microfossil classification is an important discipline in subsurface exploration,for both oil&gas and Carbon Capture and Storage(CCS).The abundance and distribution of species found in sedimentary rocks provide valuable information about the age and depositional environment.However,the analysis is difficult and consuming,time-as it is based on manual work by human experts.Attempts to automate this process face two key challenges:(1)the input data are very large-our dataset is projected to grow to 3 billion microfossils,and(2)there are not enough labeled data to use the standard procedure of training a deep learning classifier.We propose an efficient pipeline for processing and grouping fossils by genus,or even species,from microscope slides using self-supervised learning.First we show how to efficiently extract crops from whole slide images by adapting previously trained object detection algorithms.Second,we provide a comparison of a range of self-supervised learning methods to classify and identify microfossils from very few labels.We obtain excellent results with both convolutional neural networks and vision transformers fine-tuned by self-supervision.Our approach is fast and computationally light,providing a handy tool for geologists working with microfossils. 展开更多
关键词 Self-supervised learning Palynology Deep learning Microfossils
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Sound waves in fluidized bed using CFD-DEM simulations 被引量:4
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作者 Hassan Abbas Khawaja 《Particuology》 SCIE EI CAS CSCD 2018年第3期126-133,共8页
The speed of sound waves in a fluidized bed is investigated using CFD-DEM numerical simulations, Appro- priate initial and boundary conditions are applied to reproduce bed phenomena. The effect of varying the height o... The speed of sound waves in a fluidized bed is investigated using CFD-DEM numerical simulations, Appro- priate initial and boundary conditions are applied to reproduce bed phenomena. The effect of varying the height of the bed is also studied. The results of the simulations matched those from the literature. The pressure and particle velocity profiles obtained feature oscillatory behavior to which functions (based on a damped standing wave) were fitted, enabling an explicit dependence on time and space variables to be established. These fitted functions were substituted into the linearized governing equations for the two-phase flow. These solutions enabled a new relationship to be derived for the speed of sound and damping in the system. The conclusion drawn is tbat the damping in the system is governed by the effective bulk viscosity of the solid phase, which arises from the particle viscosity. 展开更多
关键词 Fluidized bed Sound waves Speed of sound Damping time CFD-DEM simulations
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Optimized cutoff maternal age for adverse obstetrical outcomes: a multicenter retrospective cohort study in Urban China during 2011 to 2012 被引量:5
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作者 Xiao-Lei Zhang Huan Liang +3 位作者 Huan-Qiang Zhao Su-Wen Wu Qiong-Jie Zhou Xiao-Tian Li 《Chinese Medical Journal》 SCIE CAS CSCD 2020年第3期269-276,共8页
Background:China’s two-child policy has led to a trend of aging in pregnancy which was associated with adverse outcomes.This study aimed to identify the clinically cutoff maternal age for adverse obstetric outcomes i... Background:China’s two-child policy has led to a trend of aging in pregnancy which was associated with adverse outcomes.This study aimed to identify the clinically cutoff maternal age for adverse obstetric outcomes in China.Methods:This secondary analysis of a multicenter retrospective cohort study included data of childbearing women from 39 hospitals collected in urban China during 2011 to 2012.Logistic regression was used to assess the adjusted odds ratios(aOR)of adverse outcomes in different age groups in comparison to women aged 20 to 24 years.The adjustments included the location of the hospital,educational level,and residence status.Clinically cutoff age was defined as the age above which the aOR continuously become both statistically(P<0.05)and clinically(aOR>2)significant.Results:Overall,108,059 women were recruited.In primiparae,clinically cutoff maternal ages for gestational diabetes(aOR:2.136,95%confidence interval[CI]:1.856-2.458,P<0.001),placenta previa(aOR:2.400,95%CI:1.863-3.090,P<0.001),cesarean section(aOR:2.511,95%CI:2.341-2.694,P<0.001),hypertensive disorder(aOR:2.122,95%CI:1.753-2.569,P<0.001),post-partum hemorrhage(aOR:2.129,95%CI:1.334-3.397,P<0.001),and low birth weight(aOR:2.174,95%CI:1.615-2.927,P<0.001)were 27,31,33,37,41,and 41 years,respectively.In multiparae,clinically cutoff ages for gestational diabetes(aOR:2.977,95%CI:1.808-4.904,P<0.001),hypertensive disorder(aOR:2.555,95%CI:1.836-3.554,P<0.001),cesarean section(aOR:2.224,95%CI:1.952-2.534,P<0.001),post-partum hemorrhage(aOR:2.140,95%CI:1.472-3.110,P<0.001),placenta previa(aOR:2.272,95%CI:1.375-3.756,P<0.001),macrosomia(aOR:2.215,95%CI:1.552-3.161,P<0.001),and neonatal asphyxia(aOR:2.132,95%CI:1.461-3.110,P<0.001)were 29,31,33,35,35,41,and 41 years,respectively.Conclusions:Early cutoff ages for gestational diabetes and cesarean section highlight a reasonable childbearing age in urban China.The various optimized cutoff ages for different adverse pregnancy outcomes should be carefully considered in childbearing women. 展开更多
关键词 Maternal age Pregnancy outcomes Clinical alarms PARITY
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Implementation of International Society Guidelines on Chorionicity Determination in Twins:A Multi-Center Cohort Study in China's Mainland 被引量:1
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作者 Su-Wen Wu Qiong-Jie Zhou +6 位作者 Xi-Rong Xiao Yu Xiong Huan Liang Jie Shen Jon Barrett Hong Wang Xiao-Tian Li 《Reproductive and Developmental Medicine》 CSCD 2020年第1期42-52,共11页
Objective:Ultrasound determination of chorionicity is poor in early pregnancy in China.In an effort to increase the accuracy rate of prompt chorionicity determination,clinical training was provided to primary care phy... Objective:Ultrasound determination of chorionicity is poor in early pregnancy in China.In an effort to increase the accuracy rate of prompt chorionicity determination,clinical training was provided to primary care physicians.This study assesses the effects of implementing clinical guidelines on chorionicity determination.Methods:A multi-centered cohort study was conducted between January 2014 and June 2017 in 12 hospitals without fetal medicine centers.In 2014,the obstetricians and ultrasound physicians were trained in clinical practice and ultrasound examination relating to chorionicity determination.Linear and binary regression analyses were conducted to identify the effects of introducing the new protocols,including the diagnosis rate of chorionicty and perinatal outcomes,taking the data from 2014 as a baseline.Pregnancy outcomes were additionally adjusted for maternal age.Results:During the period of this study,3,599 twin pregnancies from 12 centers were enrolled,and a total of 2,998 twin pregnancies were extracted.The rate of overall chorionicity determination,including antenatal and postpartum diagnosis,increased successively from 49.5% in 2014 to 93.5% in 2017(P<0.0001).The rate of ultrasonic chorionicity diagnosis before 14 weeks increased from 25.2% in 2014 to 65.0% in 2017(P<0.0001).These changes were associated with decreasing incidence of preterm birth,a lower risk of stillbirth,whether for one(P=0.0456 in 2016)or two fetuses(P=0.0470 in 2016;P=0.0042 in 2017)and a decreased rate of admission to neonatal intensive care unit(43.0% in 2014,37.4% in 2017;P=0.0032).Conclusions:The implementation of a clinical practice guideline improved both overall and early chorionicity determinations.Regular training workshops of antenatal care are recommended to further promote capability in clinical diagnosis and treatment. 展开更多
关键词 Chorionicity Determination Clinical and Ultrasound Training Community Hospitals Guideline Implementation Pregnancy Outcome
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The GCC-Russia-China LNG Triangle: The Role of Transnational Knowledge Networks and Epistemic Communities to Govern Complex Systems
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作者 Rasmus GjedssøBertelsen 《Asian Journal of Middle Eastern and Islamic Studies》 2018年第4期484-499,I0006,共17页
This paper analyzes and discusses the prospects for GCC-Russia-China transnational knowledge networks and epistemic communities in natural gas and liquified natural gas(LNG)production and trade.The premise of the arti... This paper analyzes and discusses the prospects for GCC-Russia-China transnational knowledge networks and epistemic communities in natural gas and liquified natural gas(LNG)production and trade.The premise of the article is that transnational knowledge relations between academia,government,business,civil society and wider facilitate political,economic,technological and strategic relations between countries.This article looks at the role and potential of transnational knowledge relations and epistemic communications between the GCC,Russia(focus on Russian Arctic)and China in the field of natural gas and LNG production and trade.In addition,the article will briefly expand on these transnational,transdisciplinary knowledge relations to include Japan,South Korea and other Arctic LNG producers as Norway and Alaska. 展开更多
关键词 GCC Russia China LNG energy politics liquified natural gas
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Dietary intake of advanced glycation endproducts(AGEs)and cancer risk across more than 20 anatomical sites:A multinational cohort study
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作者 Reynalda Córdova Ana-Lucia Mayén +30 位作者 Viktoria Knaze Elom Kouassivi Aglago Casper Schalkwijk Karl-Heinz Wagner Kim Overvad Anne Tjønneland Cecilie Kyrø Verena Andrea Katzke Charlotte Le Cornet Matthias Bernd Schulze Anna Birukov Domenico Palli Sara Grioni Fabrizio Pasanisi Alberto Catalano Torkjel Manning Sandanger Inger Torhild Gram Guri Skeie Marta Crous-Bou Esther Molina-Montes Pilar Amiano Sandra Milena Colorado-Yohar Eva Ardanaz Isabel Drake Jonas Manjer Ingegerd Johansson Anders Esberg Aurora Perez-Cornago Elisabete Weiderpass Mazda Jenab Heinz Freisling 《Cancer Communications》 SCIE 2022年第10期1041-1045,共5页
Dear Editor,In the European region,which shares 22.8%of the global cancer burden for 10%of the global population,there were around 4.4 million new cancer cases and 1.9 million deaths from cancer in 2020[1].The reasons... Dear Editor,In the European region,which shares 22.8%of the global cancer burden for 10%of the global population,there were around 4.4 million new cancer cases and 1.9 million deaths from cancer in 2020[1].The reasons for the high cancer incidence rates are complex;however,diet and dietary components are among the main contributors to cancer risk[2].In modern-day living,a growing proportion of people include in their diets ultra-processed foods.Byproducts of food processing and home-prepared foods are so-called dietary advanced glycation endproducts(AGEs),which are reactive metabolites emerging during the breakdown of reducing sugar.AGEs production is preponderant in dry high-heat processes(e.g.,baking,roasting);hence foods such as cakes,crisps,crackers,cereal products,meat and meat-derived products represent a major source of dietary AGEs[3]. 展开更多
关键词 dietary INTAKE hence
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Towards seamless environmental prediction-development of Pan-Eurasian EXperiment(PEEX)modelling platform
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作者 Alexander Mahura Alexander Baklanov +46 位作者 Risto Makkonen Michael Boy Tuukka Petäjä Hanna KLappalainen Roman Nuterman Veli-Matti Kerminen Stephen R.Arnold Markus Jochum Anatoly Shvidenko Igor Esau Mikhail Sofiev Andreas Stohl Tuula Aalto Jianhui Bai Chuchu Chen Yafang Cheng Oxana Drofa Mei Huang Leena Järvi Harri Kokkola Rostislav Kouznetsov Tingting Li Piero Malguzzi Sarah Monks Mads Bruun Poulsen Steffen M.Noe Yuliia Palamarchuk Benjamin Foreback Petri Clusiu Till Andreas Soya Rasmussen Jun She Jens Havskov Sørensen Dominick Spracklen Hang Su Juha Tonttila Siwen Wang Jiandong Wang Tobias Wolf-Grosse Yongqiang Yu Qing Zhang Wei Zhang Wen Zhang Xunhua Zheng Siqi Li Yong Li Putian Zhou Markku Kulmala 《Big Earth Data》 EI 2024年第2期189-230,共42页
The Pan-Eurasian Experiment Modelling Platform(PEEX-MP)is one of the key blocks of the PEEX Research Programme.The PEEX MP has more than 30 models and is directed towards seamless envir-onmental prediction.The main fo... The Pan-Eurasian Experiment Modelling Platform(PEEX-MP)is one of the key blocks of the PEEX Research Programme.The PEEX MP has more than 30 models and is directed towards seamless envir-onmental prediction.The main focus area is the Arctic-boreal regions and China.The models used in PEEX-MP cover several main components of the Earth’s system,such as the atmosphere,hydrosphere,pedosphere and biosphere,and resolve the physicalchemicalbiological processes at different spatial and temporal scales and resolutions.This paper introduces and discusses PEEX MP multi-scale modelling concept for the Earth system,online integrated,forward/inverse,and socioeconomical modelling,and other approaches with a particular focus on applications in the PEEX geographical domain.The employed high-performance com-puting facilities,capabilities,and PEEX dataflow for modelling results are described.Several virtual research platforms(PEEXView,Virtual Research Environment,Web-based Atlas)for handling PEEX modelling and observational results are introduced.The over-all approach allows us to understand better physical-chemicalbiological processes,Earth’s system interactions and feedbacks and to provide valuable information for assessment studies on evaluating risks,impact,consequences,etc.for population,envir-onment and climate in the PEEX domain.This work was also one of the last projects of Prof.Sergej Zilitinkevich,who passed away on 15 February 2021.Since the finalization took time,the paper was actually submitted in 2023 and we could not argue that the final paper text was agreed with him. 展开更多
关键词 Multi-scale and-processes modelling concept seamless coupling high-performance computing data infrastructure virtual research platforms
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