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Polyprotein Cross-linked Hydrogels with High Stretchability,Fracture Toughness and Low Hysteresis

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Chemical Research in Chinese Universities 2020年第6期36卷 1141-1142页

作者： liu dongsheng Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084P.R.China

It is challenging to realize both high fracture toughness and low hysteresis perfectly in synthetic systems,which restricts the use of stretchable hydrogels in load-bearing ***,by imbedding the folded polyprotein cross-linker in a percolating random coiled network,Cao et *** a highly stretchable hydrogel,which shows low hysteresis(<5%)but achieves high fracture toughness(ca.900 J/m^2).Moreover,the hydrogel shows outstanding anti-fatigue properties with a fatigue fracture threshold of 126 J/m^*** unique network structure breaks the hysteresis-toughness correlation that is usually reported in stretchable and tough *** work has been published in the Nature Communications and can be reached at https://***/10.1038/s41467-020-17877-z.

关键词： toughness fatigue fracture

Nucleic Acid-Backboned Chimeric Polymers with Designable Physics and Chemistry

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Chinese Journal of Chemistry 2023年第8期41卷 951-957页

作者： Jiangming Wang Yuanchen Dong Huajie liu dongsheng liu School of Chemical Science and Engineering Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education and Shanghai Research Institute for Intelligent Autonomous SystemsTongji UniversityShanghai200092 China CAS Key Laboratory of Colloid Interface and Chemical ThermodynamicsBeijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190 China Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing100084 China

Comprehensive Summary The chain effect of polymer is the kernel of the precise synthesis of complex polymer compounds and the development of polymer *** acids,a special type of polyester,can form supramolecular polymers via hydrogen bonds among corresponding *** focused on the precise control of polymer chains and proposed the concept of“nucleic acid-backboned chimeric polymers”(NCPs).There are three important elements of NCPs,namely nucleic acid backbone,side group and intra-/inter-chain weak *** this review,we expound how to realize the construction of intelligent DNA structures through the regulation of these three elements and the applications of NCPs in various fields.

关键词： Chimeric polymers Programmable polymers Kinetically interlocking Self-assembly DNA

Forcing mechanisms for East-Asia monsoonal variations during the Late Pleistocene

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Chinese Science Bulletin 1998年第18期43卷 1497-1510页

作者： Zhongli Ding dongsheng liu Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China

Based on the climate records derived from loess deposits in north-central China, the characteristics of the East-Asia paleomonsoonal changes during the Late Pleistocene are summarized as follows: (ⅰ) The 0.1_Ma climate period is predominant in both summer and winter monsoonal changes over East Asia; (ⅱ) The East-Asia monsoonal variation is different from the Indian monsoon during the Late Pleistocene; (ⅲ) There is a ～5_ka time lag of the East-Asia monsoon changes relative to the theoretically calculated solar radiation changes; (ⅳ) There is a general trend toward increase in winter monsoon and decrease in summer monsoon in the last glaciation; (ⅴ) In the East-Asia monsoonal region, the amplitude of glacial-to-interglacial cycles shows a remarkable increase from south to north. To explain these characteristics, a conceptual model is developed and the forcing of global ice volume variations in the monsoonal history is emphasized.

关键词： Chinese loess East_Asia paleomonsoon global ice volume.

Discrimination of two kinds of sedimentary laminae in maar lakes of China

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Chinese Science Bulletin 2000年第24期45卷 2292-2295页

作者： Guoqiang Chu Jiaqi liu dongsheng liu Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Varved lacustrine sediments have been found from high latitude to low latitude, even in tropical area. Paleoenvironmental and paleoclimatic research has increasingly relied on the use of varved sediments to provide high-resolution geochronologies and climatic reconstructions. However, a special depositional environment is necessary for varve formation and preservation. Generally, varves can be found in the sediments of maar lakes because of their special geological and hydrological environment. The preliminary research showed that a few carbonate laminations are developed in the Huguangyan maar lake, south China. They are poorly developed and not annual laminations, and may be related to periodically drought. Diatomaceous laminations are found in the maar lakes in northeast China. Diatomaceous laminations with cyclic nature corresponding with seasonal diatom blooming are the credible natural clock.

关键词： maar lake carbonate lamination diatomaceous lamination.

The noise spectral characteristics and noise reduction schemes of screw air-source heat pump:A case study

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Building Simulation 2024年第1期17卷 53-70页

作者： dongsheng liu Yaohan Feng Jikang Jia Pengfei Si Ya Feng China Southwest Architecture Design and Research Institute Co.Ltd. Chengdu 610041China CSCEC Green Construction Engineering Research Center Chengdu 610041China

The screw air-source heat pump can cause incessant high noise levels during operation,which might hinder adoption of this energy-efficient heat ***,acoustic measurements and comparison testing were performed in this *** measurements revealed that the compressor is the main noise source of the heat pump,and it shows a multipeak frequency distribution and a wide frequency spectrum under different work conditions,with multiple peaks at 63,250,and 1000 ***,a compressor sound insulation cover with broadband absorption was proposed,and it was experimentally proven that the insulation cover can reduce the maximum sound pressure level of one unit from 89.8 dBA to 79.1 ***,we proposed several noise reduction strategies and compared their noise reduction effects using computer *** results showed that the noise problem can be effectively improved through the rational design of the sound barrier and the layout and opening options of heat *** distance between the sound barrier and heat pump and the sound attenuation due to diffraction ALa exhibit a U-shaped *** buildings of different heights,the optimal heights of noise barrier are *** 5.5-meter is the optimal height of the sound barrier for single-story *** conclusions can be applied to other building projects for heat pump noise reduction.

关键词： acoustic simulation broadband noise noise reduction air-source heat pump sound barrier

Clinical implications of hedgehog signaling pathway inhibitors

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Chinese Journal of Cancer 2011年第1期30卷 13-26页

作者： Hailan liu dongsheng Gu Jingwu Xie Wells Center for Pediatric Research Division of Hematology and Oncology Department of Pediatrics Indiana University Simon Cancer Center Indiana University Indianapolis Indiana 46202 USA.

Hedgehog was first described in Drosophila melanogaster by the Nobel laureates Eric Wieschaus and Christiane Nüsslein-Volhard. The hedgehog (Hh) pathway is a major regulator of cell differentiation, proliferation, tissue polarity, stem cell maintenance, and carcinogenesis. The first link of Hh signaling to cancer was established through studies of a rare familial disease, Gorlin syndrome, in 1996. Follow-up studies revealed activation of this pathway in basal cell carcinoma, medulloblastoma and, leukemia as well as in gastrointestinal, lung, ovarian, breast, and prostate cancer. Targeted inhibition of Hh signaling is now believed to be effective in the treatment and prevention of human cancer. The discovery and synthesis of specific inhibitors for this pathway are even more exciting. In this review, we summarize major advances in the understanding of Hh signaling pathway activation in human cancer, mouse models for studying Hh- mediated carcinogenesis, the roles of Hh signaling in tumor development and metastasis, antagonists for Hh signaling and their clinical implications.

关键词： Hedgehog 信号通路临床意义抑制剂癌症治疗细胞分化前列腺癌预防效果

A Recommendation Approach Based on Bayesian Networks for Clone Refactor

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Computers, Materials & Continua 2020年第9期64卷 1999-2012页

作者： Ye Zhai Celimuge Wu dongsheng liu Rongrong She Inner Mongolia Normal University Hohhot010022China Graduate School of Informatics and Engineering The University of Electro-CommunicationsTokyo182-8585Japan

Reusing code fragments by copying and pasting them with or without minor adaptation is a common activity in software *** a result,software systems often contain sections of code that are very similar,called code *** clones are beneficial in reducing software development costs and development ***,recent studies have indicated some negative impacts as a *** order to effectively manage and utilize the clones,we design an approach for recommending refactoring clones based on a Bayesian ***,clone codes are detected from the source ***,the clones that need to be refactored are identified,and the static and evolutions features are extracted to build the feature ***,the Bayesian network classifier is used for training and evaluating the classification *** on more than 640 refactor examples of five open source software developed in C,we observe a considerable *** results show that the accuracy of the approach is larger than 90%.We believe our approach will provide a more accurate and reasonable code refactoring and maintenance advice for software developers.

关键词： Clone code clone refactor feature extraction Bayesian network

Magnetic susceptibility properties of polluted soils

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Chinese Science Bulletin 2000年第18期45卷 1723-1726页

作者： Luo Wang dongsheng liu Houyuan Lü Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

An investigation of magnetic properties using magnetic susceptibility ( x) andfrequency-dependent susceptibility (xfd) was conducted on representative modern pollutants, which include smelted slag dust, automobile exhaust dust and coal ash. Their magnetic susceptibility values are more than 500×108 m3/kg, and frequency-dependent susceptibility values less than 3%, indicating that ample ferrimagnetic and scanty superparamagnetic grains occurred in the studied pollutants. Similar to the artificially synthetic polluted soils, the industrially-polluted soils display a negative relationship between magnetic susceptibility and frequency-dependent susceptibility. However, the unpolluted soils, e.g. the Quaternary loess in the Chinese Loess Plateau, show a positive relationship between them. In this note, we propose a convenient and effective approach for identifying the polluted soils.

关键词： polluted soil magnetic susceptibility frequency-dependent susceptibility.

Stepwise advance of the Mu Us Desert since late Pliocene:Evidence from a red clay-loess record

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Chinese Science Bulletin 1999年第13期44卷 1211-1214页

作者： Zhongli Ding Jimin Sun dongsheng liu Institute of Geology Chinese Academy of Sciences Beijing China

Analyses of paleomagnetic polarity reversals, magnetic susceptibility and grain size on the red clay-loess sequence, about 280 m thick, at Jingbian show that this sequence contains most of the stratigraphic units recorded in the standard red clay-loess sections of the Loess Plateau over the past 3.5 Ma. Using sand particle percentage ( > 63 μm%) of the eolian sequence as a proxy indicator of desert extent and aridity in the dust source regions, it is found that during the past 3.5 Ma, there are three important climatic events indicating the advance of the Mu Us Desert. The events occurred at about 2.6, 1.1 and 0.6 MaBP, respectively. The stepwise advance of the Mu Us Desert may be linked closely to increase in global ice volume and uplift of the Tibetan Plateau in the late Cenozoic.

关键词： loess desert Quaternary.