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  1. Article ; Online: Transition state barriers in multidimensional Marcus theory.

    Zwickl, Jill / Shenvi, Neil / Schmidt, J R / Tully, John C

    The journal of physical chemistry. A

    2008  Volume 112, Issue 42, Page(s) 10570–10579

    Abstract: Multidimensional Marcus theory is the extension of traditional Marcus theory to systems ... in which multiple particles are transferred. Rather than the intersecting parabolas of Marcus theory ... multidimensional Marcus theory involves the intersection of paraboloids. In this paper, we examine the conditions ...

    Abstract Multidimensional Marcus theory is the extension of traditional Marcus theory to systems in which multiple particles are transferred. Rather than the intersecting parabolas of Marcus theory, multidimensional Marcus theory involves the intersection of paraboloids. In this paper, we examine the conditions under which a full multidimensional treatment of these paraboloids is necessary and when it is possible to use a simpler one-dimensional formalism. In particular, we examine transition state barrier energies, which are essential parameters in many reaction rate equations, and which depend on the formalism used. We find, based on both analytic calculations and numerical simulation, that the reduced one-dimensional treatment yields excellent agreement with the exact, multidimensional results over a wide variety of conditions for one particular choice of the single collective reaction coordinate. We also outline a procedure for calculating accurate multidimensional transition state barrier energies and apply it to a two-dimensional model of proton-coupled electron transfer.
    MeSH term(s) Computer Simulation ; Electrons ; Models, Chemical ; Quantum Theory ; Solvents/chemistry ; Thermodynamics
    Chemical Substances Solvents
    Language English
    Publishing date 2008-10-23
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ISSN 1520-5215
    ISSN (online) 1520-5215
    DOI 10.1021/jp805065g
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Online: Sources, transport, and partitioning of organic matter from 40 surface sediment samples at the NW Iberian margin, supplementary data to: Schmidt, Frauke; Hinrichs, Kai-Uwe; Elvert, Marcus (2010): Sources, transport, and partitioning of organic matter at a highly dynamic continental margin. Marine Chemistry, 118(1-2), 37-55

    Schmidt, Frauke / Elvert, Marcus / Hinrichs, Kai-Uwe

    2010  

    Abstract: Continental shelves play a major role as transition zone during transport of multiply-sourced organic matter into the deep sea. In order to obtain a comprehensive understanding of the origin and fractionation processes of organic matter at the NW Iberian ...

    Abstract Continental shelves play a major role as transition zone during transport of multiply-sourced organic matter into the deep sea. In order to obtain a comprehensive understanding of the origin and fractionation processes of organic matter at the NW Iberian margin, 40 surface sediment samples were analyzed for a structurally diverse range of lipid biomarkers, lignin phenols, grain size distribution, organic carbon content (TOC), its stable carbon isotopic composition (d13CTOC), and the organic carbon to nitrogen ratio (TOC/TN). The biomarker inventory reflected a heterogeneous mixture of organic matter from various marine and terrestrial sources. Soil- and vascular plant-derived continental organic matter, indicated by lignin phenols and plant-derived triterpenoids, was primarily associated with the silt fraction and transported by river run-off. The spatial distribution patterns of higher plant-derived waxes, long-chain n-alkanes, n-alcohols, and n-fatty acids suggested distinct different transport mechanisms and/or sources. The branched tetraether index, a molecular proxy expressing the relative abundance of branched dialkyl tetraethers vs. crenarchaeol and considered to signal soil-derived organic matter, was not as sensitive as the other molecular indicators in detecting continental organic matter. Hydrodynamic sorting processes on the shelf resulted in a separation of different types of terrestrial organic matter; grass and leaf fragments and soil organic matter were preferentially transported offshore and deposited in areas of lower hydrodynamic energy. Algal lipid biomarker distributions indicated a complex community of marine plankton contributing to organic matter. Spatial and seasonal patterns of phytoplankton growth primarily controlled the distribution of algal organic matter components. The interplay of all of these processes controls production, distribution, and deposition of organic matter and results in three distinct provinces at the Galicia-Minho shelf: (I) fresh marine organic matter dominated the inner shelf region; (II) high inputs of terrestrial organic matter and high TOC content characterized the mid-shelf deposited mudbelt; (III) lower concentrations of relatively degraded organic matter with increased proportions of refractory terrestrial components dominated the outer shelf and continental slope.
    Language English
    Dates of publication 2010-9999
    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.marchem.2009.10.003
    DOI 10.1594/PANGAEA.733992
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  3. Book: Marcus Behmer als Illustrator

    Behmer, Marcus / Halbey, Hans Adolf / Schmidt-Künsemüller, Friedrich Adolf / Thiersch, Frieda

    (Monographien und Materialien zur Buchkunst ; 4)

    1970  

    Author's details mit einer Einl. von Hans Adolf Halbey
    Series title Monographien und Materialien zur Buchkunst ; 4
    Language German
    Size [28] Bl., überw. Ill., 4°
    Publisher Tiessen
    Publishing place Neu-Isenburg
    Document type Book
    Note Die Vorlage enth. insgesamt 2 Werke ; With: Handeinbände von Frieda Thiersch zu Drucken der Bremer Presse / mit einer Einl. Von F. A. Schmidt-Künsemüller
    ISBN 3920947096 ; 9783920947099
    Database Former special subject collection: coastal and deep sea fishing

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  4. Book ; Online: Sediment and organic matter properties, and molecular formula from sampling locations in the Northern Black Sea, supplementary data to: Schmidt, Frauke; Koch, Boris P; Elvert, Marcus; Schmidt, Gunnar; Witt, Matthias; Hinrichs, Kai-Uwe (2011): Diagenetic transformation of dissolved organic nitrogen compounds under contrasting sedimentary redox conditions in the Black Sea. Environmental Science & Technology, 45(12), 5223-5229

    Schmidt, Frauke / Elvert, Marcus / Hinrichs, Kai-Uwe / Koch, Boris P / Schmidt, Gunnar / Witt, Matthias

    2011  

    Abstract: Remineralization of organic matter in reactive marine sediments releases nutrients and dissolved organic matter (DOM) into the ocean. Here we focused on the molecular-level characterization of DOM by high-resolution Fourier transform ion cyclotron ... ...

    Abstract Remineralization of organic matter in reactive marine sediments releases nutrients and dissolved organic matter (DOM) into the ocean. Here we focused on the molecular-level characterization of DOM by high-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) in sediment pore waters and bottom waters from contrasting redox regimes in the northern Black Sea with particular emphasis on nitrogen-bearing compounds to derive an improved understanding of the molecular transformations involved in nitrogen release. The number of nitrogen-bearing molecules is generally higher in pore waters than in bottom waters. This suggests intensified degradation of nitrogen-bearing precursor molecules such as proteins in anoxic sediments: No significant difference was observed between sediments deposited under oxic vs anoxic conditions (average O/C ratios of 0.55) suggesting that the different organic matter quality induced by contrasting redox conditions does not impact protein diagenesis in the subseafloor. Compounds in the pore waters were on average larger, less oxygenated, and had a higher number of unsaturations. Applying a mathematical model, we could show that the assemblages of nitrogen-bearing molecular formulas are potential products of proteinaceous material that was transformed by the following reactions: (a) hydrolysis and deamination, both reducing the molecular size and nitrogen content of the products and intermediates; (b) oxidation and hydration of the intermediates; and (c) methylation and dehydration.
    Language English
    Dates of publication 2011-9999
    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:10.1021/es2003414
    DOI 10.1594/PANGAEA.767386
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  5. Article: Which Patients Need Chemotherapy? From Pathological Risk Factors to Gene Signatures and Evaluation of Endocrine Response.

    Schmidt, Marcus

    Breast care (Basel, Switzerland)

    2023  Volume 18, Issue 6, Page(s) 422–427

    Abstract: Background: Chemotherapy, used either before or after surgery, has significantly improved survival in early breast cancer. Accurate risk assessment is essential to avoid both overtreatment and undertreatment. This review provides an overview of the ... ...

    Abstract Background: Chemotherapy, used either before or after surgery, has significantly improved survival in early breast cancer. Accurate risk assessment is essential to avoid both overtreatment and undertreatment. This review provides an overview of the evolution of chemotherapy as well as risk factors for tailored systemic therapies in early breast cancer - from pathologic risk factors to gene expression signatures to endocrine response assessment.
    Summary: Chemotherapy has improved dramatically in recent decades from its beginnings with conventionally dosed cyclophosphamide plus methotexate plus 5-fluorouracil to dose-dense anthracycline- and taxane-containing regimens. Similarly, risk assessment has evolved starting from traditional pathologic risk factors such as tumor size, axillary nodal status, and grading. In recent decades, gene expression signatures have improved prognostic accuracy with a high level of evidence. In turn, these signatures can be further improved by incorporating the aforementioned pathologic factors. As an important step away from this static assessment, dynamic assessment of proliferation factor Ki-67 after short-term preoperative endocrine treatment has gained interest to improve risk assessment in early hormone receptor-positive breast cancer.
    Key message: This review highlights advances in chemotherapy and risk assessment in early breast cancer, from pathologic risk factors for recurrence to gene expression signatures and endocrine response assessment. These developments are leading to better risk stratification and thus better adaptation of therapies.
    Language English
    Publishing date 2023-04-25
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2202236-3
    ISSN 1661-3805 ; 1661-3791
    ISSN (online) 1661-3805
    ISSN 1661-3791
    DOI 10.1159/000530818
    Database MEDical Literature Analysis and Retrieval System OnLINE

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    In stock of ZB MED Cologne/Königswinter

    Zs.A 6620: Show issues Location:
    Je nach Verfügbarkeit (siehe Angabe bei Bestand)
    bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
    ab Jg. 2022: Lesesaal (EG)

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  6. Book ; Conference proceedings ; Thesis: Prevalence of Schistosoma mansoni in pregnant women attending antenatal care in a Madagascan highland village determined by a rapid urine antigen test

    Schmidt-Hellerau, Kirsten / Altfeld, Marcus / Schwarz, Norbert

    2020  

    Institution Universität Hamburg
    Event/congress Universität Hamburg (MedizinischeFakultät)
    Author's details vorgelegt von: Kirsten Schmidt-Hellerau ; Prüfungsausschuss, der/die Vorsitzende: Prof. Dr. Marcus Altfeld, Prüfungsausschuss, zweite/r Gutachter/in: Prof. Dr. Norbert Schwarz
    Language English
    Size 62 Blätter, Diagramme, 30 cm
    Publishing place Hamburg
    Publishing country Germany
    Document type Book ; Conference proceedings ; Thesis
    Thesis / German Habilitation thesis Dissertation, Universität Hamburg, 2020
    Note Literaturverzeichnis: Blatt 51-59
    HBZ-ID HT020891914
    Database Catalogue ZB MED Medicine, Health

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    In stock of ZB MED Cologne/Königswinter

    Shelf markLoan statusLocation
    2021 E 420 order for loan Magazin

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  7. Article ; Online: What's on the rise in Sexually Transmitted Infections?

    Schmidt, Axel Jeremias / Marcus, Ulrich

    The Lancet regional health. Europe

    2023  Volume 34, Page(s) 100764

    Language English
    Publishing date 2023-10-26
    Publishing country England
    Document type Journal Article
    ISSN 2666-7762
    ISSN (online) 2666-7762
    DOI 10.1016/j.lanepe.2023.100764
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Book ; Online: Waldartenlisten der Farn- und Blütenpflanzen, Moose und Flechten Deutschlands

    Schmidt, Marcus

    (BfN-Skripten ; 299)

    2011  

    Institution Deutschland / Bundesamt für Naturschutz
    Author's details Red.: Marcus Schmidt ... [Hrsg.: Bundesamt für Naturschutz]
    Series title BfN-Skripten ; 299
    BfN-Skripten / Bundesamt für Naturschutz
    Collection BfN-Skripten / Bundesamt für Naturschutz
    Language German ; English
    Size 111 S. : graph. Darst., Kt.
    Publisher BfN
    Publishing place Bonn
    Publishing country Germany
    Document type Book ; Online
    Note Zsfassung in engl. Sprache. - Literaturangaben
    HBZ-ID HT017521205
    ISBN 978-3-89624-034-7 ; 3-89624-034-X
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  9. Book: Waldartenlisten der Farn- und Blütenpflanzen, Moose und Flechten Deutschlands

    Schmidt, Marcus

    (BfN-Skripten ; 299)

    2011  

    Institution Deutschland / Bundesamt für Naturschutz
    Author's details Red.: Marcus Schmidt ... [Hrsg.: Bundesamt für Naturschutz, Bonn]
    Series title BfN-Skripten ; 299
    BfN-Skripten / Bundesamt für Naturschutz
    Collection BfN-Skripten / Bundesamt für Naturschutz
    Language German
    Size 111 S. : graph. Darst., Kt.
    Publisher BfN, Bundesamt für Naturschutz
    Publishing place Bonn
    Publishing country Germany
    Document type Book
    Note Zsfassung in engl. Sprache. - Literaturangaben
    HBZ-ID HT017008547
    ISBN 978-3-89624-034-7 ; 3-89624-034-X
    Database Catalogue ZB MED Nutrition, Environment, Agriculture

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    In stock of ZB MED Bonn / Germany

    Shelf markLoan statusLocation
    114/733 available for loan (reading room) Freihandmagazin (U1)

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  10. Article: Marcus Behmer als Illustrator

    Schmidt-Künsemüller, F. A / Thiersch, Frieda

    Marcus Behmer als Illustrator, Halbey, Hans Adolf. - Neu-Isenburg : Tiessen

    1970  

    Size Ill.
    Document type Article
    Database Former special subject collection: coastal and deep sea fishing

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