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  1. Article ; Online: One-pot cascade Michael-Michael-aldol condensation for diastereoselective synthesis of nitro-substituted cyclohexanes.

    Chen, Yunfeng / Zhong, Cheng / Sun, Xiaohua / Akhmedov, Novruz G / Petersen, Jeffrey L / Shi, Xiaodong

    Chemical communications (Cambridge, England)

    2009  , Issue 34, Page(s) 5150–5152

    Abstract: A one-pot reaction of nitroalkenes and enones was developed for the preparation of nitro-vinyl-substituted cyclohexanes, which could be simply converted into poly-N-heterocycles. ...

    Abstract A one-pot reaction of nitroalkenes and enones was developed for the preparation of nitro-vinyl-substituted cyclohexanes, which could be simply converted into poly-N-heterocycles.
    MeSH term(s) Alkenes/chemistry ; Cyclohexanes/chemical synthesis ; Cyclohexanes/chemistry ; Ketones/chemistry ; Molecular Structure ; Nitro Compounds/chemistry ; Stereoisomerism
    Chemical Substances Alkenes ; Cyclohexanes ; Ketones ; Nitro Compounds
    Language English
    Publishing date 2009-09-14
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1472881-3
    ISSN 1364-548X ; 1359-7345 ; 0009-241X
    ISSN (online) 1364-548X
    ISSN 1359-7345 ; 0009-241X
    DOI 10.1039/b909766j
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Ionic liquid mediated Cu-catalyzed cascade oxa-Michael-oxidation: efficient synthesis of flavones under mild reaction conditions.

    Du, Zhiyun / Ng, Huifen / Zhang, Kun / Zeng, Huaqiang / Wang, Jian

    Organic & biomolecular chemistry

    2011  Volume 9, Issue 20, Page(s) 6930–6933

    Abstract: ... we disclose a highly efficient synthetic method of CuI-catalyzed cascade oxa-Michael-oxidation, using ...

    Abstract Flavonoids are a class of natural products, found in a wide range of vascular plants and dietary components. Their low toxicity and extensive biological activities, including anti-cancer and anti-bacterial, have made them attractive candidates to serve as therapeutic agents for many diseases. Herein, we disclose a highly efficient synthetic method of CuI-catalyzed cascade oxa-Michael-oxidation, using chalcones as substrates, mediated by the ionic liquid [bmim][NTf2] at a low temperature. This efficient synthetic method has demonstrated high synthetic utility and can afford flavones in good to high yields (up to 98%).
    MeSH term(s) Catalysis ; Copper/chemistry ; Flavones/chemical synthesis ; Iodides/chemistry ; Ionic Liquids/chemistry ; Molecular Structure ; Oxidation-Reduction
    Chemical Substances Flavones ; Iodides ; Ionic Liquids ; Copper (789U1901C5) ; cuprous iodide (7DE9CA6IL2)
    Language English
    Publishing date 2011-10-21
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2097583-1
    ISSN 1477-0539 ; 1477-0520
    ISSN (online) 1477-0539
    ISSN 1477-0520
    DOI 10.1039/c1ob06209c
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Book ; Online ; E-Book: Practical management of urinary stone

    Wong, Michael Y. C. / Ng, Anthony C. F. / Isotani, Shuji

    2021  

    Author's details edited by Anthony C. F. Ng, Michael Y. C. Wong, and Shuji Isotani
    Keywords Urology ; Càlculs renals ; Urologia
    Subject code 016.616980213
    Language English
    Size 1 online resource (246 pages)
    Publisher Springer
    Publishing place Singapore
    Document type Book ; Online ; E-Book
    Remark Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    ISBN 981-16-4193-5 ; 981-16-4192-7 ; 978-981-16-4193-0 ; 978-981-16-4192-3
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  4. Book ; Online ; E-Book: Sports injuries of the elbow

    Watts, Adam C. / Funk, Lennard / Hayton, Michael / Ng, Chye Yew / Walton, Mike

    2021  

    Author's details Adam C. Watts, Lennard Funk, Michael Hayton, Chye Yew Ng, Mike Walton editors
    Keywords Orthopedics ; Sports medicine
    Subject code 616.7
    Language English
    Size 1 Online-Ressource (V, 123 Seiten)
    Publisher Springer
    Publishing place Cham
    Publishing country Switzerland
    Document type Book ; Online ; E-Book
    Remark Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    HBZ-ID HT030394292
    ISBN 978-3-030-52379-4 ; 9783030523787 ; 3-030-52379-9 ; 3030523780
    DOI 10.1007/978-3-030-52379-4
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  5. Book ; Online: Calcium isotopic composition of planktonic foraminifera from ODP Site 154-925, supplementary data to: Sime, NG; De La Rocha, Christina L; Tipper, Edward T; Tripati, Aradhna; Galy, Albert; Bickle, Michael J (2007): Interpreting the Ca isotope record of marine biogenic carbonates. Geochimica et Cosmochimica Acta, 71(16), 3979-3989

    Sime, NG / Bickle, Michael J / De La Rocha, Christina L / Galy, Albert / Tipper, Edward T / Tripati, Aradhna

    2007  

    Abstract: An 18 million year record of the Ca isotopic composition (d44/42Ca) of planktonic foraminiferans from ODP site 925, in the Atlantic, on the Ceara Rise, provides the opportunity for critical analysis of Ca isotope-based reconstructions of the Ca cycle. ? ... ...

    Abstract An 18 million year record of the Ca isotopic composition (d44/42Ca) of planktonic foraminiferans from ODP site 925, in the Atlantic, on the Ceara Rise, provides the opportunity for critical analysis of Ca isotope-based reconstructions of the Ca cycle. ?44/42Ca in this record averages +0.37+/-0.05 (1 sigma SD) and ranges from +0.21? to +0.52?. The record is a good match to previously published Neogene Ca isotope records based on foraminiferans, but is not similar to the record based on bulk carbonates, which has values that are as much as 0.25? lower. Bulk carbonate and planktonic foraminiferans from core tops differ slightly in their d44/42Ca (i.e., by 0.06+/-0.06? (n = 5)), while the difference between bulk carbonate and foraminiferan values further back in time is markedly larger, leaving open the question of the cause of the difference. Modeling the global Ca cycle from downcore variations in d44/42Ca by assuming fixed values for the isotopic composition of weathering inputs (d44/42Ca_w) and for isotope fractionation associated with the production of carbonate sediments (D_sed) results in unrealistically large variations in the total mass of Ca2+ in the oceans over the Neogene. Alternatively, variations of +/-0.05? in the Ca isotope composition of weathering inputs or in the extent of fractionation of Ca isotopes during calcareous sediment formation could entirely account for variations in the Ca isotopic composition of marine carbonates. Ca isotope fractionation during continental weathering, such as has been recently observed, could easily result in variations in d44/42Ca_w of a few tenths of permil. Likewise a difference in the fractionation factors associated with aragonite versus calcite formation could drive shifts in D_sed of tenths of permil with shifts in the relative output of calcite and aragonite from the ocean. Until better constraints on variations in d44/42Ca_w and D_sed have been established, modeling the Ca2+ content of seawater from Ca isotope curves should be approached cautiously.
    Language English
    Dates of publication 2007-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.gca.2007.06.009
    DOI 10.1594/PANGAEA.711216
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  6. Article: [Besprechung von:] Webber, Michael J.: Impact of uncertainty on location. Canberra 1972

    Ng, Yew-kwang / Webber, Michael J

    The economic record : er Vol. 48 , p. 603-605

    1972  Volume 48, Page(s) 603–605

    Author's details Yew-kwang Ng
    Publisher Blackwell Publ. Asia
    Publishing place Carlton South, Vic.
    Document type Article
    ZDB-ID 203689-7
    Database ECONomics Information System

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  7. Article ; Online: FastHyMix: Fast and Parameter-Free Hyperspectral Image Mixed Noise Removal.

    Zhuang, Lina / Ng, Michael K

    IEEE transactions on neural networks and learning systems

    2023  Volume 34, Issue 8, Page(s) 4702–4716

    Abstract: The decrease in the widths of spectral bands in hyperspectral imaging leads to a decrease in signal-to-noise ratio (SNR) of measurements. The decreased SNR reduces the reliability of measured features or information extracted from hyperspectral images ( ... ...

    Abstract The decrease in the widths of spectral bands in hyperspectral imaging leads to a decrease in signal-to-noise ratio (SNR) of measurements. The decreased SNR reduces the reliability of measured features or information extracted from hyperspectral images (HSIs). Furthermore, the image degradations linked with various mechanisms also result in different types of noise, such as Gaussian noise, impulse noise, deadlines, and stripes. This article introduces a fast and parameter-free hyperspectral image mixed noise removal method (termed FastHyMix), which characterizes the complex distribution of mixed noise by using a Gaussian mixture model and exploits two main characteristics of hyperspectral data, namely, low rankness in the spectral domain and high correlation in the spatial domain. The Gaussian mixture model enables us to make a good estimation of Gaussian noise intensity and the locations of sparse noise. The proposed method takes advantage of the low rankness using subspace representation and the spatial correlation of HSIs by adding a powerful deep image prior, which is extracted from a neural denoising network. An exhaustive array of experiments and comparisons with state-of-the-art denoisers was carried out. The experimental results show significant improvement in both synthetic and real datasets. A MATLAB demo of this work is available at https://github.com/LinaZhuang for the sake of reproducibility.
    Language English
    Publishing date 2023-08-04
    Publishing country United States
    Document type Journal Article
    ISSN 2162-2388
    ISSN (online) 2162-2388
    DOI 10.1109/TNNLS.2021.3112577
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Correction: Can we stop routine biopsy of post-endoscopic mucosal resection scars?

    Burgess, Nicholas G / Bourke, Michael J

    Endoscopy

    2023  Volume 55, Issue 7, Page(s) C4

    Language English
    Publishing date 2023-06-07
    Publishing country Germany
    Document type Journal Article ; Published Erratum
    ZDB-ID 80120-3
    ISSN 1438-8812 ; 0013-726X
    ISSN (online) 1438-8812
    ISSN 0013-726X
    DOI 10.1055/a-2106-6895
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Endoscopic Submucosal Dissection Versus Endoscopic Mucosal Resection of Large Colon Polyps: Use Both for the Best Outcomes.

    Burgess, Nicholas G / Bourke, Michael J

    Annals of internal medicine

    2023  Volume 177, Issue 1, Page(s) 89–90

    MeSH term(s) Humans ; Endoscopic Mucosal Resection ; Colonic Polyps/surgery ; Colonoscopy ; Colon ; Treatment Outcome
    Language English
    Publishing date 2023-12-12
    Publishing country United States
    Document type Editorial ; Comment
    ZDB-ID 336-0
    ISSN 1539-3704 ; 0003-4819
    ISSN (online) 1539-3704
    ISSN 0003-4819
    DOI 10.7326/M23-3185
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Can we stop routine biopsy of post-endoscopic mucosal resection scars?

    Burgess, Nicholas G / Bourke, Michael J

    Endoscopy

    2023  Volume 55, Issue 7, Page(s) 608–610

    MeSH term(s) Humans ; Endoscopic Mucosal Resection/adverse effects ; Cicatrix/etiology ; Cicatrix/prevention & control ; Cicatrix/pathology ; Biopsy/adverse effects ; Stomach Neoplasms/surgery
    Language English
    Publishing date 2023-06-01
    Publishing country Germany
    Document type Editorial ; Comment
    ZDB-ID 80120-3
    ISSN 1438-8812 ; 0013-726X
    ISSN (online) 1438-8812
    ISSN 0013-726X
    DOI 10.1055/a-2085-5660
    Database MEDical Literature Analysis and Retrieval System OnLINE

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