Ultrahigh-pressure and Retrograde Metamorphic Ages for Paleozoic Protolith of Paragneiss in the Main Drill Hole of the Chinese Continental Scientific Drilling Project(CCSD-MH),SW Sulu UHP Terrane

Laser Raman spectroscopy and cathodoluminescence （CL） images show that most zircon crystals separated from paragneiss in the main drill hole of the Chinese Continental Scientific Drilling Project （CCSD-MH） at Maobei, southwestern Sulu terrane, contain low-pressure mineral-bearing detrital cores, coesite-bearing mantles and quartz-bearing or mineral inclusion-free rims. SHRIMP U-Pb dating on these zoned zircons yield three discrete and meaningful age groups. The detrital cores yield a large age span from 659 to 313 Ma, indicating the protolith age for the analyzed paragnelss is Paleozoic rather than Proterozoic. The coesite-bearing mantles yield a weighted mean age of 228 ± 5 Ma for the UHP event. The quartz-bearing outmost rims yield a weighted mean age of 213 ± 6 Ma for the retrogressive event related to the regional amphibolite facies metamorphism in the Sulu UHP terrane. Combined with previous SHRIMP U-Pb dating results from orthogneiss in CCSD-MH, it is suggested that both Neoproterozoic granitic protolith and Paleozoic sedimentary rocks were subducted to mantle depths in the Late Triassic. About 15 million years later, the Sulu UHP metamorphic rocks were exhumed to mid-crustal levels and overprinted by an amphibolite-facies retrogressive metamorphism. The exhumation rate deduced from the SHRIMP data and metamorphic P-T conditions is about 6.7 km/Ma. Such a fast exhumation suggests that the Sulu UHP paragnelss and orthogneiss returned towards the surface as a dominant part of a buoyant sliver, caused as a consequence of slab breakoff.

Automatic Keyphrase Extraction from Scientific Chinese Medical Abstracts Based on Character-Level Sequence Labeling

Purpose:Automatic keyphrase extraction(AKE)is an important task for grasping the main points of the text.In this paper,we aim to combine the benefits of sequence labeling formulation and pretrained language model to propose an automatic keyphrase extraction model for Chinese scientific research.Design/methodology/approach:We regard AKE from Chinese text as a character-level sequence labeling task to avoid segmentation errors of Chinese tokenizer and initialize our model with pretrained language model BERT,which was released by Google in 2018.We collect data from Chinese Science Citation Database and construct a large-scale dataset from medical domain,which contains 100,000 abstracts as training set,6,000 abstracts as development set and 3,094 abstracts as test set.We use unsupervised keyphrase extraction methods including term frequency(TF),TF-IDF,TextRank and supervised machine learning methods including Conditional Random Field(CRF),Bidirectional Long Short Term Memory Network(BiLSTM),and BiLSTM-CRF as baselines.Experiments are designed to compare word-level and character-level sequence labeling approaches on supervised machine learning models and BERT-based models.Findings:Compared with character-level BiLSTM-CRF,the best baseline model with F1 score of 50.16%,our character-level sequence labeling model based on BERT obtains F1 score of 59.80%,getting 9.64%absolute improvement.Research limitations:We just consider automatic keyphrase extraction task rather than keyphrase generation task,so only keyphrases that are occurred in the given text can be extracted.In addition,our proposed dataset is not suitable for dealing with nested keyphrases.Practical implications:We make our character-level IOB format dataset of Chinese Automatic Keyphrase Extraction from scientific Chinese medical abstracts(CAKE)publicly available for the benefits of research community,which is available at:https://github.com/possible1402/Dataset-For-Chinese-Medical-Keyphrase-Extraction.Originality/value:By designing comparative experiments,our study demonstrates that character-level formulation is more suitable for Chinese automatic keyphrase extraction task under the general trend of pretrained language models.And our proposed dataset provides a unified method for model evaluation and can promote the development of Chinese automatic keyphrase extraction to some extent.

A Study on the Classification and Well-Logging Identification of Eclogite in the Main Hole of Chinese Continental Scientific Drilling Project

Eclogite, one of the important lithologies in the main hole of the Chinese Continental Scientific Drilling （CCSD） Project, exists above the depth of 3 245 m and has distinctive responses of gamma-ray, compensating density and neutron well-logging, and so on. In this study, according to the diversities of minerals and chemical components and well-logging responses, edogites are classified from three aspects of origin, content of oxygen, and sub-mineral. We studied the logging identification method for eclogite sub-classes based on multi-element statistics and reconstructed 11 kinds of eclogite. As a result, eclogites can be divided into 6 types using well logs. In the light of this recognition, the eclogite in the main hole is divided into 20 sections, and the distribution characters of all sub-classes of eclogite are analyzed, which will provide important data for geological research of CCSD.

Acoustic Borehole Images for Fracture Extraction and Analysis in Second Pre-pilot Drillhole of CCSD

Ultrasonic imaging logging provides continuous and oriented images of structures vs. depth. In the Chinese Continental Scientific Drilling (CCSD) Project, acoustic borehole images were recorded in the second pre-pilot drillhole which penetrates the metamorphic rocks. This paper focuses on fracture evaluation of the drillhole with these images. Both least square fit and a modified Hough transform are used for fracture extraction, and 269 fractures were mapped in the interval from 69.5 to 1 020 m. Most fractures dip steeply, with an average angle of 54°. Fracture dip directions are dominantly in the range of 220°-280° above the depth of 267 m, but 80°-120° in the lower zones. These observations may indicate the differences in structural movements or in-situ stress fields between the upper and lower zones in the drillhole.

Ethnic Chinese Medicine,Borderless Civilization--On the Identity of Humane and Scientific Nature of Chinese and Western Medicines

The identity of Eastern and Western cultures should include aspects such as its concepts of societal development and science and technology.Though this is related to issues like history of the culture and regional cultural psychologies,the essence lies in the identity of social values at its core.

Scientific understanding of toxicity and safety of Chinese medicines

Traditional Chinese medicine is a treasure of traditional culture and medicine which should be inherited and developed. How to cor- rectly understand the toxicity of Chinese materia medica （CMM） is an important guarantee for safe drug use. The history of the applica- tion and research of the toxicity of CMM has been long, and the Chi- nese medicine community ,has never stopped exploring the issues related to the safety of CMM.

Celebrate the 3^(rd) Workshop on Scientific Approaches to Chinese Medicine

The 3^(rd) workshop on Scientific Approaches to Chinese Medicine is held by German-Chinese Research Foundation for Traditional Chinese Medicine (DCFG-TCM)。

3^(rd) Workshop on Scientific Approaches to Chinese Medicine

Date: October 24^(th)-27^(th), 2008 Place: Huangshan City, Anhui Province, China (To be announced for details in October)Organizers:Chinese-German Research

Annotation and Joint Extraction of Scientific Entities and Relationships in NSFC Project Texts

Aiming at the lack of classification and good standard corpus in the task of joint entity and relationship extraction in the current Chinese academic field, this paper builds a dataset in management science that can be used for joint entity and relationship extraction, and establishes a deep learning model to extract entity and relationship information from scientific texts. With the definition of entity and relation classification, we build a Chinese scientific text corpus dataset based on the abstract texts of projects funded by the National Natural Science Foundation of China(NSFC) in 2018–2019. By combining the word2vec features with the clue word feature which is a kind of special style in scientific documents, we establish a joint entity relationship extraction model based on the Bi LSTM-CNN-CRF model for scientific information extraction. The dataset we constructed contains 13060 entities(not duplicated) and 9728 entity relation labels. In terms of entity prediction effect, the accuracy rate of the constructed model reaches 69.15%, the recall rate reaches 61.03%, and the F1 value reaches 64.83%. In terms of relationship prediction effect, the accuracy rate is higher than that of entity prediction, which reflects the effectiveness of the input mixed features and the integration of local features with CNN layer in the model.

Establishing distinctive theories and methods of design science rooted in Chinese traditional culture

The human social development saw the formation of five unique civilizations,with the latter forming their own distinctive cultures.China’s traditional culture is its most fundamental ideological weapon for solving problems.The Chinese are good at comprehensive thinking,dialectical thinking,and systematic analysis.These ideological weapons can solve the problems of formal science and technology and create scientific and technological achievements on par with global advanced scale.Ancient China is filled with original scientific and technological achievements,which strongly prove ancient China’s possession of its own science and technology different from that of Western Renaissance.Therefore,a comprehensive understanding of science,technology,experience,and intuition is necessary.The long-held superstition regarding the West,the lack of confidence,self-denial,blind imitation of ideas,and shackles must be thrown away.Only then can we take the road toward an authentic Chinese creative design as we learn from others.