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  1. Article ; Online: Impacts of Hurricane Michael on Watershed Hydrology

    Elijah Worley / Ning Liu / Ge Sun / Steven P. Norman / William M. Christie / Michael Gavazzi / Johnny Boggs / Steven G. McNulty

    Forests, Vol 13, Iss 904, p

    A Case Study in the Southeastern United States

    2022  Volume 904

    Abstract: ... in coastal watersheds. This case study focused on Hurricane Michael, a recent catastrophic event that impacted the Gulf ... this study suggests that changes in vegetation cover after Hurricane Michael did not have lasting impacts ...

    Abstract Hurricanes are one of the most significant threats to coastal plain forest ecosystems and urban communities of the southeastern U.S., but their implications for watershed hydrology are unclear. Hurricanes have the potential to alter water balances, causing extensive flooding, biogeochemical cycle disruption, and water quality degradation, saltwater intrusion, and increased nutrient sedimentation export in coastal watersheds. This case study focused on Hurricane Michael, a recent catastrophic event that impacted the Gulf coast, the Florida panhandle, southwestern Georgia, and southeastern Alabama. Through empirical (Double Mass Curve) and process-based ecohydrological modeling (WaSSI model) on long-term streamflow data, we explored whether vegetation damage caused by this hurricane resulted in an increase in streamflow two years after the extreme event. We found that monthly streamflow from the Chipola River watershed with an area of 2023 km 2 did not change (<6%) appreciably during the first two years following the storm, arguably because only a fraction of the gauged watershed lost substantial tree cover. However, spatially explicit hydrological modeling suggested that several sub-watersheds with the highest decreases in the Normalized Difference Vegetation Index (NDVI) significantly increased their monthly streamflow in 2019 by up to 22%. These modeled streamflow anomalies subsided by the second growing season when vegetation recovered. Overall, this study suggests that changes in vegetation cover after Hurricane Michael did not have lasting impacts on the hydrology of this watershed, and the hydrology of coastal watersheds may be more resilient to hurricane disturbances than previously thought.
    Keywords forest disturbance ; Hurricane Michael ; hydrology ; modeling ; Plant ecology ; QK900-989
    Subject code 333
    Language English
    Publishing date 2022-06-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: The mechanism of thia-Michael addition catalyzed by LanC enzymes.

    Ongpipattanakul, Chayanid / Liu, Shi / Luo, Youran / Nair, Satish K / van der Donk, Wilfred A

    Proceedings of the National Academy of Sciences of the United States of America

    2023  Volume 120, Issue 3, Page(s) e2217523120

    Abstract: ... occurs in various biological processes. In bacteria, intramolecular thia-Michael addition catalyzed ...

    Abstract In both eukarya and bacteria, the addition of Cys to dehydroalanine (Dha) and dehydrobutyrine (Dhb) occurs in various biological processes. In bacteria, intramolecular thia-Michael addition catalyzed by lanthipeptide cyclases (LanC) proteins or protein domains gives rise to a class of natural products called lanthipeptides. In eukarya, dehydroamino acids in signaling proteins are introduced by effector proteins produced by pathogens like
    MeSH term(s) Humans ; Peptides/chemistry ; Proteins ; Glutathione ; Bacteria/metabolism ; Catalysis ; Oxygen
    Chemical Substances Peptides ; Proteins ; Glutathione (GAN16C9B8O) ; Oxygen (S88TT14065)
    Language English
    Publishing date 2023-01-12
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2217523120
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Cu-catalyzed carboboration of acetylene with Michael acceptors.

    Cheng, Tairan / Liu, Boxiang / Wu, Rui / Zhu, Shifa

    Chemical science

    2022  Volume 13, Issue 25, Page(s) 7604–7609

    Abstract: A copper-catalyzed three-component carboboration of acetylene with ... ...

    Abstract A copper-catalyzed three-component carboboration of acetylene with B
    Language English
    Publishing date 2022-06-08
    Publishing country England
    Document type Journal Article
    ZDB-ID 2559110-1
    ISSN 2041-6539 ; 2041-6520
    ISSN (online) 2041-6539
    ISSN 2041-6520
    DOI 10.1039/d2sc02306g
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Glutathione-Induced In Situ Michael Addition between Nanoparticles for Pyroptosis and Immunotherapy.

    Zhen, Wenyao / Liu, Yang / An, Shangjie / Jiang, Xiue

    Angewandte Chemie (International ed. in English)

    2023  Volume 62, Issue 20, Page(s) e202301866

    Abstract: ... equilibria and simultaneously reacting with intracellular GSH in a Michael addition to form large aggregates ...

    Abstract Most tumor treatments will fail when ignoring competition and cooperation between each cancer cell and its microenvironment. Inspired by game theory, therapeutic agents can be introduced to compete for intracellular molecules to disrupt the cooperation between molecules and cells. Biomineralized oxidized (-)-epigallocatechin-3-o-gallate (EGCG)-molybdenum ion coordination nanoparticles were prepared for disrupting redox equilibria and simultaneously reacting with intracellular GSH in a Michael addition to form large aggregates that can mechanically disrupt endosomal and plasma membranes, stimulating pyroptosis and anti-tumor immunological responses for versatile inhibition of different types of tumors. This design disrupts the cooperation between molecules and between cancer and immune cells, achieving an optimal payoff in competition and cooperation in cancer therapy.
    MeSH term(s) Pyroptosis ; Glutathione ; Oxidation-Reduction ; Immunotherapy ; Nanoparticles
    Chemical Substances Glutathione (GAN16C9B8O)
    Language English
    Publishing date 2023-04-12
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2011836-3
    ISSN 1521-3773 ; 1433-7851
    ISSN (online) 1521-3773
    ISSN 1433-7851
    DOI 10.1002/anie.202301866
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: A Thiol-Michael Approach Towards Versatile Functionalized Cyclic Titanium-Oxo Clusters.

    Li, Xing-Han / Dai, Shuqi / Yan, Xiao-Yun / Lei, Huanyu / Liu, Xian-You / Liu, Yuchu / Zhang, Weiqi / Xu, Xiaotong / Yin, Jia-Fu / Wu, Yuean / Ye, Feng / Guo, Qing-Yun / Cheng, Stephen Z D

    Chemistry (Weinheim an der Bergstrasse, Germany)

    2023  Volume 29, Issue 63, Page(s) e202302352

    Abstract: ... challenge to material scientists. Herein, we report an efficient thiol-Michael addition approach ...

    Abstract In expanding our research activities of superlattice engineering, designing new giant molecules is the necessary first step. One attempt is to use inorganic transition metal clusters as building blocks. Efficient functionalization of chemically precise transition metal clusters, however, remains a great challenge to material scientists. Herein, we report an efficient thiol-Michael addition approach for the modifications of cyclic titanium-oxo cluster (CTOC). Several advantages, including high efficiency, mild reaction condition, capability of complete addition, high atom economy, as well as high functional group tolerance were demonstrated. This approach can afford high yields of fully functionalized CTOCs, which provides a powerful platform for achieving versatile functionalization of precise transition metal clusters and further applications.
    Language English
    Publishing date 2023-10-02
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1478547-X
    ISSN 1521-3765 ; 0947-6539
    ISSN (online) 1521-3765
    ISSN 0947-6539
    DOI 10.1002/chem.202302352
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Discovery of Michael reaction acceptors from the leaves of Ailanthus altissima by a modified tactic.

    Duan, Zhi-Kang / Guo, Shan-Shan / Ye, Li / Gao, Zhi-Heng / Liu, Dai / Yao, Guo-Dong / Song, Shao-Jiang / Huang, Xiao-Xiao

    Phytochemistry

    2023  Volume 215, Page(s) 113858

    Abstract: ... in the isolation and identification of seven undescribed potential Michael reaction acceptors (1-7). Ailanlactone ...

    Abstract Structural characteristics-guided investigation of Ailanthus altissima (Mill.) Swingle resulted in the isolation and identification of seven undescribed potential Michael reaction acceptors (1-7). Ailanlactone A (1) possesses an unusual 1,7-epoxy-11,12-seco quassinoid core. Ailanterpene B (6) was a rare guaianolide-type sesquiterpene with a 5/6/6/6-fused skeleton. Their structures were determined through extensive analysis of physiochemical and spectroscopic data, quantum chemical calculations, and single crystal X-ray crystallographic technology using Cu Kα radiation. The cytotoxic activities of isolates on HepG2 and Hep3B cells were evaluated in vitro. Encouragingly, ailanaltiolide K (4) showed significant cytotoxicity against Hep3B cells with IC
    MeSH term(s) Ailanthus/chemistry ; Plant Extracts/chemistry ; Plant Leaves ; Quassins/chemistry
    Chemical Substances Plant Extracts ; Quassins
    Language English
    Publishing date 2023-09-13
    Publishing country England
    Document type Journal Article
    ZDB-ID 208884-8
    ISSN 1873-3700 ; 0031-9422
    ISSN (online) 1873-3700
    ISSN 0031-9422
    DOI 10.1016/j.phytochem.2023.113858
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Facile fabrication of cellulose-based hydrophobic paper via Michael addition reaction.

    Liu, Hongchen / Guo, Lei / Dai, Yamin / Li, Mengya / Wang, Dongwei / Li, Yun / Qi, Haisong

    International journal of biological macromolecules

    2023  Volume 253, Issue Pt 8, Page(s) 127513

    Abstract: ... to obtain CAA graft acrylate (CAA-X) fibers through Michael addition reaction. Subsequently, CAA-X fibers ...

    Abstract The inherent highly hydrophilic feature of cellulose-based paper hinders its application in many fields. Herein, a cellulose-based hydrophobic paper was fabricated based on surface chemical modification. Firstly, the hydrophobic acrylate components were bonded to the cellulose acetoacetate (CAA) fibers to obtain CAA graft acrylate (CAA-X) fibers through Michael addition reaction. Subsequently, CAA-X fibers were processed into paper via wet papermaking technology. The resulting paper exhibited good hydrophobic performance (water contact angle was up to 135°) with an air permeability of 24.8 μm/Pa·s. The hydrophobicity of paper was very stable and remained even after treating with different solvents. Moreover, the hydrophobic properties of this paper could be adjusted by changing the type of acrylate component. It should be noted that the surface modification strategy has no obvious effects on the whiteness (79.8%), writing, and printing properties of the cellulose fibers. Thus, it is a simple, benign, and efficient strategy for the construction of cellulose-based hydrophobic paper, which has great potential to be used in paper tableware, oil-water separation, watercolor protection, and food packaging fields.
    MeSH term(s) Cellulose/chemistry ; Hydrophobic and Hydrophilic Interactions ; Water/chemistry ; Solvents ; Acrylates/chemistry
    Chemical Substances Cellulose (9004-34-6) ; Water (059QF0KO0R) ; Solvents ; acrylic acid (J94PBK7X8S) ; Acrylates
    Language English
    Publishing date 2023-10-19
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 282732-3
    ISSN 1879-0003 ; 0141-8130
    ISSN (online) 1879-0003
    ISSN 0141-8130
    DOI 10.1016/j.ijbiomac.2023.127513
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Asymmetric Tandem Michael Addition/Interrupted Nef Reactions of Nitromethane with Oxindole-Derived Alkenes: Enantioselective Synthesis of Spiro-polycyclic Oxindoles.

    Liu, Shengshu / Yang, Yu-Chen / Yang, Yong-Qi / Li, Xin / Wang, Pengfei / Li, Yin-Long / Deng, Jun

    Organic letters

    2024  Volume 26, Issue 15, Page(s) 3279–3283

    Abstract: ... Michael addition/interrupted Nef reaction of nitromethane with oxindole-derived alkenes catalyzed ...

    Abstract Chiral spiro-polycyclic oxindoles are valuable heterocyclic ring systems that are widely distributed in natural alkaloids and biologically active compounds. Herein, we reported an asymmetric tandem Michael addition/interrupted Nef reaction of nitromethane with oxindole-derived alkenes catalyzed by a chiral 2-aminobenzimidazole bifunctional organocatalyst. A series of novel enantiomerically enriched spiro-polycyclic oxindole derivatives bearing an oxime group were synthesized in moderate to excellent isolated yields (up to 99%) with an excellent level of enantioselectivities (up to 99% ee). Furthermore, the antiproliferation activity of the resulting oxindoles derivatives were evaluated, and compound
    Language English
    Publishing date 2024-04-05
    Publishing country United States
    Document type Journal Article
    ISSN 1523-7052
    ISSN (online) 1523-7052
    DOI 10.1021/acs.orglett.4c00919
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Impacts of Hurricane Michael on Watershed Hydrology: A Case Study in the Southeastern United States

    Worley, Elijah / Liu, Ning / Sun, Ge / Norman, Steven P. / Christie, William M. / Gavazzi, Michael / Boggs, Johnny / McNulty, Steven G.

    Forests. 2022 June 09, v. 13, no. 6

    2022  

    Abstract: ... in coastal watersheds. This case study focused on Hurricane Michael, a recent catastrophic event that impacted the Gulf ... this study suggests that changes in vegetation cover after Hurricane Michael did not have lasting impacts ...

    Abstract Hurricanes are one of the most significant threats to coastal plain forest ecosystems and urban communities of the southeastern U.S., but their implications for watershed hydrology are unclear. Hurricanes have the potential to alter water balances, causing extensive flooding, biogeochemical cycle disruption, and water quality degradation, saltwater intrusion, and increased nutrient sedimentation export in coastal watersheds. This case study focused on Hurricane Michael, a recent catastrophic event that impacted the Gulf coast, the Florida panhandle, southwestern Georgia, and southeastern Alabama. Through empirical (Double Mass Curve) and process-based ecohydrological modeling (WaSSI model) on long-term streamflow data, we explored whether vegetation damage caused by this hurricane resulted in an increase in streamflow two years after the extreme event. We found that monthly streamflow from the Chipola River watershed with an area of 2023 km² did not change (<6%) appreciably during the first two years following the storm, arguably because only a fraction of the gauged watershed lost substantial tree cover. However, spatially explicit hydrological modeling suggested that several sub-watersheds with the highest decreases in the Normalized Difference Vegetation Index (NDVI) significantly increased their monthly streamflow in 2019 by up to 22%. These modeled streamflow anomalies subsided by the second growing season when vegetation recovered. Overall, this study suggests that changes in vegetation cover after Hurricane Michael did not have lasting impacts on the hydrology of this watershed, and the hydrology of coastal watersheds may be more resilient to hurricane disturbances than previously thought.
    Keywords biogeochemical cycles ; case studies ; coastal plains ; coasts ; exports ; forests ; hurricanes ; hydrologic cycle ; normalized difference vegetation index ; rivers ; saltwater intrusion ; stream flow ; subwatersheds ; trees ; vegetation cover ; water quality ; watershed hydrology ; Alabama ; Florida ; Georgia
    Language English
    Dates of publication 2022-0609
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    ZDB-ID 2527081-3
    ISSN 1999-4907
    ISSN 1999-4907
    DOI 10.3390/f13060904
    Database NAL-Catalogue (AGRICOLA)

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  10. Article ; Online: Thiol-Michael addition based conjugate for glutathione activation and release.

    Liu, Zhengkun / Chen, Shasha / Wang, Hao / Zhao, Yaofeng / Dong, Shouliang

    Bioorganic chemistry

    2022  Volume 129, Page(s) 106221

    Abstract: ... focused on disulfide-based conjugate. We reported here a new thiol-Michael addition based GSH response ...

    Abstract Glutathione (GSH) level has long been recognized as a valuable tumor biomarker. GSH-mediated activation and release systems have been extensively developed for cancer diagnosis and treatment, but mainly focused on disulfide-based conjugate. We reported here a new thiol-Michael addition based GSH response conjugate TC6, which consists of a unique tricyclic structure containing α, β-unsaturated ketone responsive groups. The conjugate was easily synthesized and showed good selectivity to glutathione with certain stability. The camptothecin delivery experiment of TC6 showed improved anti-tumor ability in cells and tumor-bearing mice. TC6 could be used for the development of antibody or small molecule conjugated drugs.
    MeSH term(s) Mice ; Animals ; Sulfhydryl Compounds/pharmacology ; Glutathione/chemistry ; Camptothecin/chemistry ; Ketones ; Disulfides
    Chemical Substances Sulfhydryl Compounds ; Glutathione (GAN16C9B8O) ; Camptothecin (XT3Z54Z28A) ; Ketones ; Disulfides
    Language English
    Publishing date 2022-10-25
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 120080-x
    ISSN 1090-2120 ; 0045-2068
    ISSN (online) 1090-2120
    ISSN 0045-2068
    DOI 10.1016/j.bioorg.2022.106221
    Database MEDical Literature Analysis and Retrieval System OnLINE

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