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  1. Article: Construction of Cyclopropa[c]coumarins via cascade Michael-alkylation process of 3-cyanocoumarin with 2-bromomalonate

    Sun, Jun-Chao / Ji, Cong-Bin / Li, Jun-Lin / Peng, Yi-Yuan / Zeng, Xing-Ping

    Tetrahedron. 2020 Jan. 31, v. 76, no. 5

    2020  

    Abstract: ... derivatives in good to excellent yields via cascade Michael-alkylation process of 3-substituted coumarins and ... A convenient and efficient method for the synthesis of highly functionalized cyclopropa[c]coumarin ...

    Abstract A convenient and efficient method for the synthesis of highly functionalized cyclopropa[c]coumarin derivatives in good to excellent yields via cascade Michael-alkylation process of 3-substituted coumarins and 2-bromomalonate was developed. Preliminary results indicated that using a chiral PTC strategy, the desired cyclopropanation product could be obtained in up to 41% ee.
    Keywords chemical reactions ; chemical structure ; coumarin
    Language English
    Dates of publication 2020-0131
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 204285-x
    ISSN 1464-5416 ; 0040-4020 ; 0563-2064
    ISSN (online) 1464-5416
    ISSN 0040-4020 ; 0563-2064
    DOI 10.1016/j.tet.2019.130852
    Database NAL-Catalogue (AGRICOLA)

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    In stock of ZB MED Cologne/Königswinter

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  2. Article ; Online: Thiourea-Catalyzed Asymmetric Michael Addition of Carbazolones to 2-Chloroacrylonitrile: Total Synthesis of 5,22-Dioxokopsane, Kopsinidine C, and Demethoxycarbonylkopsin.

    Ni, Dongshun / Wei, Yi / Ma, Dawei

    Angewandte Chemie (International ed. in English)

    2018  Volume 57, Issue 32, Page(s) 10207–10211

    Abstract: A modified Takemoto catalyst enabled the asymmetric Michael addition of carbazolones to 2 ...

    Abstract A modified Takemoto catalyst enabled the asymmetric Michael addition of carbazolones to 2-chloroacrylonitrile to afford 3,3-disubstituted carbazolones with excellent enantioselectivity. This method was successfully applied to total syntheses of three Kopsia alkaloids which featured an unprecedented Mn
    Language English
    Publishing date 2018-07-11
    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.201805905
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  3. Article: Biomimetic syntheses of ineleganolide and sinulochmodin C from 5-episinuleptolide via sequences of transannular Michael reactions

    Li, Yi / Pattenden, Gerald

    Tetrahedron. 2011 Dec. 23, v. 67, no. 51

    2011  

    Abstract: ... believed to be biomimetic, and occur by successive transannular Michael reactions in 7. Under different ... The polycycle 30 is possibly produced from ineleganolide 1, following a reverse oxy-Michael reaction and two ... at −78°C to 0°C, leads to the polycyclic norcembranoids ineleganolide 1 and sinulochmodin C (2) (65 ...

    Abstract Treatment of a solution of the macrocyclic norcembranoid 7 with lithium hexamethyldisilazide in THF at −78°C to 0°C, leads to the polycyclic norcembranoids ineleganolide 1 and sinulochmodin C (2) (65%), which are found in the corals Sinularia inelegans and Sinularia lochmodes, respectively. The conversions are believed to be biomimetic, and occur by successive transannular Michael reactions in 7. Under different temperature conditions the novel polycycle 30 is the main product, alongside small quantities of 1 and 2. The polycycle 30 is possibly produced from ineleganolide 1, following a reverse oxy-Michael reaction and two successive aldol reactions. The significance of the synthesis of ineleganolide 1, sinulochmodin C (2) and the structure 30 from 5-episinuleptolide 7, to the likely biosynthesis of the related norcembranoids scabrolide A (3), scabrolide B (4) and horiolide 31 found in Sinularia sp. is discussed.
    Keywords Sinularia ; biomimetics ; biosynthesis ; chemical reactions ; chemical structure ; corals ; lithium ; organic compounds ; temperature
    Language English
    Dates of publication 2011-1223
    Size p. 10045-10052.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 204285-x
    ISSN 1464-5416 ; 0040-4020 ; 0563-2064
    ISSN (online) 1464-5416
    ISSN 0040-4020 ; 0563-2064
    DOI 10.1016/j.tet.2011.09.040
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  4. Article ; Online: Sixth Nerve Palsy: Takayasu Arteritis on Digital Subtraction Angiography.

    Yi, Cameron / Fara, Michael G

    Stroke

    2024  Volume 55, Issue 4, Page(s) e115–e116

    MeSH term(s) Humans ; Angiography, Digital Subtraction ; Takayasu Arteritis/complications ; Takayasu Arteritis/diagnostic imaging ; Magnetic Resonance Angiography ; Abducens Nerve Diseases/diagnostic imaging ; Abducens Nerve Diseases/etiology
    Language English
    Publishing date 2024-03-04
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80381-9
    ISSN 1524-4628 ; 0039-2499 ; 0749-7954
    ISSN (online) 1524-4628
    ISSN 0039-2499 ; 0749-7954
    DOI 10.1161/STROKEAHA.123.046078
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  5. Article ; Online: Associations between resting state functional brain connectivity and childhood anhedonia

    Yi Zhou / Narun Pat / Michael C Neale

    PLoS ONE, Vol 18, Iss 5, p e

    A reproduction and replication study.

    2023  Volume 0277158

    Abstract: Background Previously, a study using a sample of the Adolescent Brain Cognitive Development (ABCD)® study from the earlier 1.0 release found differences in several resting state functional MRI (rsfMRI) brain connectivity measures associated with children ...

    Abstract Background Previously, a study using a sample of the Adolescent Brain Cognitive Development (ABCD)® study from the earlier 1.0 release found differences in several resting state functional MRI (rsfMRI) brain connectivity measures associated with children reporting anhedonia. Here, we aim to reproduce, replicate, and extend the previous findings using data from the later ABCD study 4.0 release, which includes a significantly larger sample. Methods To reproduce and replicate the previous authors' findings, we analyzed data from the ABCD 1.0 release (n = 2437), from an independent subsample from the newer ABCD 4.0 release (excluding individuals from the 1.0 release) (n = 6456), and from the full ABCD 4.0 release sample (n = 8866). Additionally, we assessed whether using a multiple linear regression approach could improve replicability by controlling for the effects of comorbid psychiatric conditions and sociodemographic covariates. Results While the previously reported associations were reproducible, effect sizes for most rsfMRI measures were drastically reduced in replication analyses (including for both t-tests and multiple linear regressions) using the ABCD 4.0 (excluding 1.0) sample. However, 2 new rsfMRI measures (the Auditory vs. Right Putamen and the Retrosplenial-Temporal vs. Right-Thalamus-Proper measures) exhibited replicable associations with anhedonia and stable, albeit small, effect sizes across the ABCD samples, even after accounting for sociodemographic covariates and comorbid psychiatric conditions using a multiple linear regression approach. Conclusion The most statistically significant associations between anhedonia and rsfMRI connectivity measures found in the ABCD 1.0 sample tended to be non-replicable and inflated. Contrastingly, replicable associations exhibited smaller effects with less statistical significance in the ABCD 1.0 sample. Multiple linear regressions helped assess the specificity of these findings and control the effects of confounding covariates.
    Keywords Medicine ; R ; Science ; Q
    Subject code 310
    Language English
    Publishing date 2023-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Optimizing Parameters for High-resolution and Low-dose Electron Ptychography.

    Jiang, Yi / Cao, Michael C / Chen, Zhen / Han, Yimo

    Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada

    2023  Volume 29, Issue Supplement_1, Page(s) 284–285

    Language English
    Publishing date 2023-08-23
    Publishing country England
    Document type Journal Article
    ZDB-ID 1385710-1
    ISSN 1435-8115 ; 1431-9276
    ISSN (online) 1435-8115
    ISSN 1431-9276
    DOI 10.1093/micmic/ozad067.131
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  7. Article ; Online: Associations between resting state functional brain connectivity and childhood anhedonia: A reproduction and replication study.

    Zhou, Yi / Pat, Narun / Neale, Michael C

    PloS one

    2023  Volume 18, Issue 5, Page(s) e0277158

    Abstract: Background: Previously, a study using a sample of the Adolescent Brain Cognitive Development (ABCD)® study from the earlier 1.0 release found differences in several resting state functional MRI (rsfMRI) brain connectivity measures associated with ... ...

    Abstract Background: Previously, a study using a sample of the Adolescent Brain Cognitive Development (ABCD)® study from the earlier 1.0 release found differences in several resting state functional MRI (rsfMRI) brain connectivity measures associated with children reporting anhedonia. Here, we aim to reproduce, replicate, and extend the previous findings using data from the later ABCD study 4.0 release, which includes a significantly larger sample.
    Methods: To reproduce and replicate the previous authors' findings, we analyzed data from the ABCD 1.0 release (n = 2437), from an independent subsample from the newer ABCD 4.0 release (excluding individuals from the 1.0 release) (n = 6456), and from the full ABCD 4.0 release sample (n = 8866). Additionally, we assessed whether using a multiple linear regression approach could improve replicability by controlling for the effects of comorbid psychiatric conditions and sociodemographic covariates.
    Results: While the previously reported associations were reproducible, effect sizes for most rsfMRI measures were drastically reduced in replication analyses (including for both t-tests and multiple linear regressions) using the ABCD 4.0 (excluding 1.0) sample. However, 2 new rsfMRI measures (the Auditory vs. Right Putamen and the Retrosplenial-Temporal vs. Right-Thalamus-Proper measures) exhibited replicable associations with anhedonia and stable, albeit small, effect sizes across the ABCD samples, even after accounting for sociodemographic covariates and comorbid psychiatric conditions using a multiple linear regression approach.
    Conclusion: The most statistically significant associations between anhedonia and rsfMRI connectivity measures found in the ABCD 1.0 sample tended to be non-replicable and inflated. Contrastingly, replicable associations exhibited smaller effects with less statistical significance in the ABCD 1.0 sample. Multiple linear regressions helped assess the specificity of these findings and control the effects of confounding covariates.
    MeSH term(s) Adolescent ; Humans ; Child ; Brain/diagnostic imaging ; Brain Mapping ; Anhedonia ; Magnetic Resonance Imaging ; Reproduction
    Language English
    Publishing date 2023-05-04
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0277158
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  8. Article ; Online: Evaluation of hydroxyl radical and reactive chlorine species generation from the superoxide/hypochlorous acid reaction as the basis for a novel advanced oxidation process.

    Liou, Sin-Yi / Dodd, Michael C

    Water research

    2021  Volume 200, Page(s) 117142

    Abstract: The reaction of hypochlorous acid (HOCl) with superoxide radical ( ... ...

    Abstract The reaction of hypochlorous acid (HOCl) with superoxide radical (O
    MeSH term(s) Chlorine ; Disinfection ; Halogenation ; Hydroxyl Radical ; Hypochlorous Acid ; Superoxides ; Water Pollutants, Chemical/analysis ; Water Purification
    Chemical Substances Water Pollutants, Chemical ; Superoxides (11062-77-4) ; Hydroxyl Radical (3352-57-6) ; Chlorine (4R7X1O2820) ; Hypochlorous Acid (712K4CDC10)
    Language English
    Publishing date 2021-04-13
    Publishing country England
    Document type Journal Article
    ZDB-ID 202613-2
    ISSN 1879-2448 ; 0043-1354
    ISSN (online) 1879-2448
    ISSN 0043-1354
    DOI 10.1016/j.watres.2021.117142
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  9. Article ; Online: Cerebral Palsy and Motor Impairment after Extreme Prematurity: Prediction of Diagnoses at Ages 2 and 10 Years.

    Marinelli, Timothy / Yi, Joe X / O'Shea, T Michael / Joseph, Robert M / Hooper, Stephen R / Kuban, Karl C K / Sakai, Christina / Msall, Michael E / Fry, Rebecca / Singh, Rachana

    The Journal of pediatrics

    2024  , Page(s) 114037

    Abstract: Objective: To identify perinatal factors in children born extremely preterm (EP) that were associated with motor impairment (MI) at 2 and 10 years of age and develop a predictive algorithm to estimate the risk of MI during childhood.: Methods: ... ...

    Abstract Objective: To identify perinatal factors in children born extremely preterm (EP) that were associated with motor impairment (MI) at 2 and 10 years of age and develop a predictive algorithm to estimate the risk of MI during childhood.
    Methods: Participants of the ELGAN Study were classified as: no MI, MI only at 2 years, MI only at 10 years, and MI at both 2 and 10 years, based on a standardized neurological examination at 2 and the Gross Motor Function Classification System at 10 years of age. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to develop the final predictive model.
    Results: Of the 849 study participants, 64 (7.5%) had a diagnosis of MI at both 2 and 10 years and 63 (7.4%) had a diagnosis of MI at one visit but not the other. Of 22 total risk factors queried, 4 variables most reliably and accurately predicted MI: gestational age, weight z-score growth trajectory during NICU stay, ventriculomegaly, and cerebral echolucency on head ultrasound. By selecting probability thresholds of 3.5% and 7.0% at ages 2 and 10, respectively, likelihood of developing MI can be predicted with a sensitivity and specificity of 71.2%/72.1% at age 2 and 70.7%/70.7% at age 10.
    Conclusion: In our cohort, the diagnosis of MI at 2 years did not always predict a diagnosis of MI at 10 years. Specific risk factors are predictive of MI and can estimate an individual infant's risk at NICU discharge of MI at age 10 years.
    Language English
    Publishing date 2024-04-03
    Publishing country United States
    Document type Journal Article
    ZDB-ID 3102-1
    ISSN 1097-6833 ; 0022-3476
    ISSN (online) 1097-6833
    ISSN 0022-3476
    DOI 10.1016/j.jpeds.2024.114037
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  10. Article ; Online: Trends in Vascular Access Among Patients Initiating Hemodialysis in the US.

    Allon, Michael / Zhang, Yi / Thamer, Mae / Crews, Deidra C / Lee, Timmy

    JAMA network open

    2023  Volume 6, Issue 8, Page(s) e2326458

    MeSH term(s) Humans ; Renal Dialysis ; Kidney Failure, Chronic/epidemiology ; Kidney Failure, Chronic/therapy
    Language English
    Publishing date 2023-08-01
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ISSN 2574-3805
    ISSN (online) 2574-3805
    DOI 10.1001/jamanetworkopen.2023.26458
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