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A Simple and Novel Ipso-Bromination of 1-Bromomethyl-4-t-butyl-2,6-dimethylbenzene

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Chinese Chemical Letters 1997年第4期8卷 271-274页

作者： Zhang, wc Yu, ZH CHINESE ACAD SCI INST CHEMBEIJING 100080PEOPLES R CHINA

A novel ipso electrophlic substitution of 1-bromomethyl-4-t-butyl-2,6-dimethylbenzene 1 with nitric acid in alcohol, which gives ipso-bromination product of 1-bromo-4-t-butyl-2,6-dimethylbenzene 2, is described and a ... 详细信息

关键词： NITRATION

Lipases catalyzed acetylation of meso-2,4-dimethyl-1,5-pentanediol and the synthesis of Prelog-Djerassi lactone

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Chinese Journal of Chemistry 1995年第4期13卷 380-384页

作者： LIN, GQ XU, wc CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

Lipase catalyzed acetylation of 2 afforded 3 with the e.e. up to 98%. Utility of 3 was illustrated by the preparation of Prelog-Djerassi lactones 7a and 7b.

关键词： LIPASE (2R,4S)-5-ACETOXY-2,4-DIMETHYL-PENTANOL PRELOG-DJERASSI LACTONE

SHARPLESS ASYMMETRIC EPOXIDATION OF HEPTENYLPHENYLMETHYLSILANOL

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Chinese Chemical Letters 1995年第8期6卷 647-650页

作者： Feng, wc Wang, D Acad Sinica Inst Chem Beijing 100080 Peoples R China

The Sharpless asymmetric epoxidation of 1 was carried out to give the (1S,2S)-4 in 33% yield, which was protodesilylated giving (-)-5 with 50% ee. The steric effect of phenyl group on silicon upon the rate and ee of the reaction was observed. The possibility of kinetic resolution of racemic silanol under the Sharpless reaction condition was examined.

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Self-care among older Chinese people with chronic heart failure： the roles of cognitive and psychosocial characteristics

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Journal of Geriatric Cardiology 2016年第5期13卷 431-434页

作者： Doris SF Yu Polly wc Li The Nethersole School of Nursing The Chinese University of Hong Kong Hong Kong China

Chronic heart failure （CHF） is a complex clinical syndrome resulting from inefficient myocardial pumping, and is characterised by a typical progressively deteriorating trajectory punctuated by serious episodes of acute disease *** prevalence of hospital admission has been reported.[2] However, around 40% of hospital admissions was avoidable if patients demonstrate consistent self-care.

关键词： Chinese Heart failure Life experience Self-care

Ni-Ir anomaly and fusulinid extinction across the Permian-Triassic boundary in Dongluo, Guangxi

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Chinese Science Bulletin 1997年第13期42卷 1117-1119页

作者： Wang, XP Hao, wc Yang, SR Department of Geology Peking University Beijing 100871 China

SINCE Alvarez first used iridium anomaly to explain the Cretaceous-Tertiary impact eventand mass extinction, more than 70 sites of iridium-nickel anomalies have been found. The Per-mian-Triassic boundary extinction is more prominent than that of the *** leads us to make research on whether similar events happened during that period.

关键词： Permian-Triassic boundary anomalous elements fusulinid extinction.

Discovery and significance of microfossils from Qinbaikouian Dazhuang Formation in Luonan, Shaanxi Province

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Chinese Science Bulletin 1997年第3期42卷 243-245页

作者： Chen, Z Hua, H Jian, wc Hu, YX Department of Geology Northwest University Xi’an China Xi’an Institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Xi’an China

THE microfossils were obtained by using 5%—7% HF acid from Qingbaikouian Dazhuang Formation in Luonan County, Shaanxi Province, with an age of 800—1000 Ma. The fossils may be one type of the oldest skeletal mierofos... 详细信息

关键词： microfossil Qinbaikouian Dazhuang Formation Shaanxi Province.

Validation of the Physical Activity Questionnaire for Older Children(PAQ-C) among Chinese Children

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Biomedical and Environmental Sciences 2016年第3期29卷 177-186页

作者： WANG Jing Jing BARANOWSKI Tom LAU wc Patrick CHEN Tzu An PITKETHLY Amanda Jane Department of Physical Education Faculty of Social Sciences Hong Kong Baptist University Children's Nutrition Research Center Department of Pediatrics Baylor College of Medicine

Objective This study initially validates the Chinese version of the Physical Activity Questionnaire for Older Children （PAQ-C）, which has been identified as a potentially valid instrument to assess moderate-to-vigorous physical activity （MVPA） in children among diverse racial groups. Methods The psychometric properties of the PAQ-C with 742 Hong Kong Chinese children were assessed with the scale＇s internal consistency, reliability, test-retest reliability, confirmatory factory analysis （CFA） in the overall sample, and multistep invariance tests across gender groups as well as convergent validity with body mass index （BMI）, and an accelerometry-based MVPA. Results The Cronbach alpha coefficient （α=0.79）, composite reliability value （p=0.81）, and the intraclass correlation coefficient （α=0.82） indicate the satisfactory reliability of the PAQ-C score. The CFA indicated data fit a single factor model, suggesting that the PAQ-C measures only one construct, on MVPA over the previous 7 days. The multiple-group CFAs suggested that the factor Ioadings and variances and covariances of the PAQ-C measurement model were invariant across gender groups. The PAQ-C score was related to accelerometry-based MVPA （r=0.33） and inversely related to BMI （r=0.18）. Conclusion This study demonstrates the reliability and validity of the PAQ-C in Chinese children.

关键词： Physical activity Measurement Children Reliability Validity

Voltage-gated K^+channels promote BT-474 breast cancer cell migration

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Chinese Journal of Cancer Research 2018年第6期30卷 613-622页

作者： Louis wc Chow Ka-Shun Cheng Kar-Lok Wong Yuk-Man Leung State Key Laboratory of Quality Research in Chinese Medicines Macao University of Science and TechnologyTaipaMacao 999078China UNIMED Medical Institute Hong Kong 999077China Organisation for Oncology and Translational Research Hong Kong 999077China Department of Anesthesiology China Medical University HospitalTaiehung 40447TaiwanChina Department of Anesthesiology the Qingdao University Yuhuangding HospitalYantai 264000China Department of Physiology China Medical UniversityTaichung 40402TaiwanChina

Objective: A variety of ion channels have been implicated in breast cancer proliferation and *** K+(Kv) channels not only cause repolarization in excitable cells,but are also involved in multiple cellular functions in non-excitable *** this study we investigated the role of Kv channels in migration of BT474 breast cancer ***: Transwell technique was used to separate migratory cells from non-migratory ones and these two groups of cells were subject to electrophysiological examinations and microfluorimetric measurements for cytosolic *** migration was examined in the absence or presence of Kv channel ***: When compared with non-migratory cells,migratory cells had much higher Kv current densities,but rather unexpectedly,more depolarized membrane potential and reduced *** transcriptasepolymerase chain reaction(RT-PCR) analysis revealed the presence of Kv1.1,Kv1.3,Kv1.5,Kv2.1,Kv3.3,Kv3.4 and Kv4.3 *** migration was markedly inhibited by tetraethylammonium(TEA),a delayed rectifier Kv channel blocker,but not by 4-aminopyridine,an A-type Kv channel ***: Taken together,our results show that increased Kv channel expression played a role in BT474 cell migration,and Kv channels could be considered as biomarkers or potential therapeutic targets for breast cancer *** mechanism(s) by which Kv channels enhanced migration appeared unrelated to membrane hyperpolarization and Cainflux.

关键词： Breast cancer Kv channels migration biomarkers

Synthesized AI LMI-based Criterion for Mechanical Systems

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Sound & Vibration 2019年第6期53卷 245-250页

作者： Jcy Chen wc Chen Tim Chen Alex Wilson NFadilah Jamaludin Nertrand Kapron Tim Chen John Burno Faculty of Information Technology Ho Chi Minh City UniversityHo Chi Minh CityVietnam Department of Data Science RMIT UniversityMelbourneVICAustralia School of Physical and Mathematical Technology Nanyang Technological University21 Nanyang LinkSingaporeSingapore Faculty of Engineering King Abdulaziz UniversityJeddah 21589Saudi Arabia Heidelberg Academy of Sciences HeidelbergBaden-WürttembergGermany

This paper proposes a novel artificial intelligence sythethized controller in the mechanical system which has high speed computation because of the LMI type *** proposed membership functions are adopted and stabilization criterion of the closed-loop T-S fuzzy systems are obtained through a new parametrized LMI(linear matrix)inequality which is rearranged by machine learning membership functions.

关键词： Fuzzy energy equation artificial intelligence large-scale systems fuzzy model