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  1. Artikel ; Online: Framing as a Concept for Health Communication: A Systematic Review.

    Guenther, Lars / Gaertner, Maria / Zeitz, Jessica

    Health communication

    2020  Band 36, Heft 7, Seite(n) 891–899

    Abstract: Over the past decades, research in the fields of both framing and health communication has grown exponentially. However, to date, no systematic review has been conducted about how framing - as a concept - has been used in health communication. The ... ...

    Abstract Over the past decades, research in the fields of both framing and health communication has grown exponentially. However, to date, no systematic review has been conducted about how framing - as a concept - has been used in health communication. The present study provides a systematic review of the current research, applying a quantitative content analysis to the published literature on framing in health communication. Articles published in peer-reviewed scientific journals (
    Mesh-Begriff(e) Communication ; Health Communication ; Humans ; Vaccination
    Sprache Englisch
    Erscheinungsdatum 2020-01-29
    Erscheinungsland England
    Dokumenttyp Journal Article ; Systematic Review
    ZDB-ID 1038723-7
    ISSN 1532-7027 ; 1041-0236
    ISSN (online) 1532-7027
    ISSN 1041-0236
    DOI 10.1080/10410236.2020.1723048
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  2. Buch ; Online: Sensitivity of ice flow to uncertainty in flow law parameters in an idealized one-dimensional geometry

    Zeitz, Maria / Levermann, Anders / Winkelmann, Ricarda

    eISSN: 1994-0424

    2020  

    Abstract: The flow of ice drives mass losses in both, the Antarctic and the Greenland Ice Sheet. The projections of possible future sea-level rise rely on numerical ice-sheet models, which solve the physics of ice flow and melt. While a number of important ... ...

    Abstract The flow of ice drives mass losses in both, the Antarctic and the Greenland Ice Sheet. The projections of possible future sea-level rise rely on numerical ice-sheet models, which solve the physics of ice flow and melt. While a number of important uncertainties have been addressed by the ice-sheet modeling community, the flow law, which is at the center of most process-based ice-sheet models, has so far been assumed certain. Unfortunately, recent studies show that the parameters in the flow law might be uncertain and different from the widely accepted standard values. Here, we use an idealized flowline setup to investigate how uncertainties in the flow law translate into uncertainties in flow-driven mass loss given a step-wise increase of surface temperatures. We find that the measured range of flow parameters can double the flow-driven mass loss within the first centuries of warming, compared to a setting with standard parameters. The spread of ice loss due to an uncertainty in flow parameters is of the same order as the increase in mass loss due to increasing surface temperatures. While this study focuses on an idealized setting in order to disentangle the effect of the flow law from other effects, it is likely that this uncertainty carries over to realistic three-dimensional simulations of Greenland and Antarctica.
    Thema/Rubrik (Code) 621
    Sprache Englisch
    Erscheinungsdatum 2020-04-07
    Erscheinungsland de
    Dokumenttyp Buch ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  3. Buch ; Online: Sensitivity of ice loss to uncertainty in flow law parameters in an idealized one-dimensional geometry

    Zeitz, Maria / Levermann, Anders / Winkelmann, Ricarda

    eISSN: 1994-0424

    2020  

    Abstract: Acceleration of the flow of ice drives mass losses in both the Antarctic and the Greenland Ice Sheet. The projections of possible future sea-level rise rely on numerical ice-sheet models, which solve the physics of ice flow, melt, and calving. While ... ...

    Abstract Acceleration of the flow of ice drives mass losses in both the Antarctic and the Greenland Ice Sheet. The projections of possible future sea-level rise rely on numerical ice-sheet models, which solve the physics of ice flow, melt, and calving. While major advancements have been made by the ice-sheet modeling community in addressing several of the related uncertainties, the flow law, which is at the center of most process-based ice-sheet models, is not in the focus of the current scientific debate. However, recent studies show that the flow law parameters are highly uncertain and might be different from the widely accepted standard values. Here, we use an idealized flow-line setup to investigate how these uncertainties in the flow law translate into uncertainties in flow-driven mass loss. In order to disentangle the effect of future warming on the ice flow from other effects, we perform a suite of experiments with the Parallel Ice Sheet Model (PISM), deliberately excluding changes in the surface mass balance. We find that changes in the flow parameters within the observed range can lead up to a doubling of the flow-driven mass loss within the first centuries of warming, compared to standard parameters. The spread of ice loss due to the uncertainty in flow parameters is on the same order of magnitude as the increase in mass loss due to surface warming. While this study focuses on an idealized flow-line geometry, it is likely that this uncertainty carries over to realistic three-dimensional simulations of Greenland and Antarctica.
    Thema/Rubrik (Code) 621
    Sprache Englisch
    Erscheinungsdatum 2020-10-27
    Erscheinungsland de
    Dokumenttyp Buch ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  4. Artikel ; Online: Dynamic regimes of the Greenland Ice Sheet emerging from interacting melt–elevation and glacial isostatic adjustment feedbacks

    Zeitz, Maria / Haacker, Jan M. / Donges, Jonathan F. / Albrecht, Torsten / Winkelmann, Ricarda

    2022  

    Abstract: The stability of the Greenland Ice Sheet under global warming is governed by a number of dynamic processes and interacting feedback mechanisms in the ice sheet, atmosphere and solid Earth. Here we study the long-term effects due to the interplay of the ... ...

    Abstract The stability of the Greenland Ice Sheet under global warming is governed by a number of dynamic processes and interacting feedback mechanisms in the ice sheet, atmosphere and solid Earth. Here we study the long-term effects due to the interplay of the competing melt–elevation and glacial isostatic adjustment (GIA) feedbacks for different temperature step forcing experiments with a coupled ice-sheet and solid-Earth model. Our model results show that for warming levels above 2 ∘C, Greenland could become essentially ice-free within several millennia, mainly as a result of surface melting and acceleration of ice flow. These ice losses are mitigated, however, in some cases with strong GIA feedback even promoting an incomplete recovery of the Greenland ice volume. We further explore the full-factorial parameter space determining the relative strengths of the two feedbacks: our findings suggest distinct dynamic regimes of the Greenland Ice Sheets on the route to destabilization under global warming – from incomplete recovery, via quasi-periodic oscillations in ice volume to ice-sheet collapse. In the incomplete recovery regime, the initial ice loss due to warming is essentially reversed within 50 000 years, and the ice volume stabilizes at 61 %–93 % of the present-day volume. For certain combinations of temperature increase, atmospheric lapse rate and mantle viscosity, the interaction of the GIA feedback and the melt–elevation feedback leads to self-sustained, long-term oscillations in ice-sheet volume with oscillation periods between 74 000 and over 300 000 years and oscillation amplitudes between 15 %–70 % of present-day ice volume. This oscillatory regime reveals a possible mode of internal climatic variability in the Earth system on timescales on the order of 100 000 years that may be excited by or synchronized with orbital forcing or interact with glacial cycles and other slow modes of variability. Our findings are not meant as scenario-based near-term projections of ice losses but rather providing insight into ...
    Thema/Rubrik (Code) 290
    Sprache Englisch
    Erscheinungsdatum 2022-07-22
    Verlag Copernicus Publications (EGU)
    Erscheinungsland de
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  5. Artikel ; Online: Thrifty energy phenotype predicts weight regain in postmenopausal women with overweight or obesity and is related to FGFR1 signaling.

    Spranger, Leonard / Weiner, January / Bredow, Josephine / Zeitz, Ulrike / Grittner, Ulrike / Boschmann, Michael / Dickmann, Sophia / Stobäus, Nicole / Schwartzenberg, Reiner Jumpertz-von / Brachs, Maria / Spranger, Joachim / Mai, Knut

    Clinical nutrition (Edinburgh, Scotland)

    2023  Band 42, Heft 4, Seite(n) 559–567

    Abstract: Background&aims: Long term improvement of body weight and metabolism is highly requested in obesity. The specific impact of weight loss associated temporary negative energy balance or modified body composition on metabolism and weight regain is unclear.! ...

    Abstract Background&aims: Long term improvement of body weight and metabolism is highly requested in obesity. The specific impact of weight loss associated temporary negative energy balance or modified body composition on metabolism and weight regain is unclear.
    Methods: We randomly assigned 80 post-menopausal women (BMI 33.9 (32.2-36.8)kg/m
    Results: Between March 2012 and July 2015, 479 subjects were screened for eligibility. 80 subjects were randomly assigned to IG (n = 40) or CG (n = 40). The total number of dropouts was 18 (IG: n = 13, CG: n = 5). LBM and ISI
    Conclusion: Negative energy balance had no additional effect on insulin sensitivity. FGFR1 signaling might be involved in the adaption of energy expenditure to temporary negative energy balance, which indicates a thrifty phenotype susceptible to weight regain.
    Trial registration: ClinicalTrials.gov number: NCT01105143, https://clinicaltrials.gov/ct2/show/NCT01105143, date of registration: April 16th, 2010.
    Mesh-Begriff(e) Female ; Humans ; Overweight ; Insulin Resistance ; Postmenopause ; Obesity/metabolism ; Body Composition ; Energy Metabolism ; Weight Gain ; Weight Loss ; Receptor, Fibroblast Growth Factor, Type 1/metabolism
    Chemische Substanzen FGFR1 protein, human (EC 2.7.10.1) ; Receptor, Fibroblast Growth Factor, Type 1 (EC 2.7.10.1)
    Sprache Englisch
    Erscheinungsdatum 2023-02-24
    Erscheinungsland England
    Dokumenttyp Randomized Controlled Trial ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 604812-2
    ISSN 1532-1983 ; 0261-5614
    ISSN (online) 1532-1983
    ISSN 0261-5614
    DOI 10.1016/j.clnu.2023.02.020
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel ; Online: Active Brownian particles moving in a random Lorentz gas.

    Zeitz, Maria / Wolff, Katrin / Stark, Holger

    The European physical journal. E, Soft matter

    2017  Band 40, Heft 2, Seite(n) 23

    Abstract: Biological microswimmers often inhabit a porous or crowded environment such as soil. In order to understand how such a complex environment influences their spreading, we numerically study non-interacting active Brownian particles (ABPs) in a two- ... ...

    Abstract Biological microswimmers often inhabit a porous or crowded environment such as soil. In order to understand how such a complex environment influences their spreading, we numerically study non-interacting active Brownian particles (ABPs) in a two-dimensional random Lorentz gas. Close to the percolation transition in the Lorentz gas, they perform the same subdiffusive motion as ballistic and diffusive particles. However, due to their persistent motion they reach their long-time dynamics faster than passive particles and also show superdiffusive motion at intermediate times. While above the critical obstacle density [Formula: see text] the ABPs are trapped, their long-time diffusion below [Formula: see text] is strongly influenced by the propulsion speed v
    Sprache Englisch
    Erscheinungsdatum 2017
    Erscheinungsland France
    Dokumenttyp Journal Article
    ZDB-ID 2004003-9
    ISSN 1292-895X ; 1292-8941
    ISSN (online) 1292-895X
    ISSN 1292-8941
    DOI 10.1140/epje/i2017-11510-0
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  7. Artikel ; Online: Feedback mechanism for microtubule length regulation by stathmin gradients.

    Zeitz, Maria / Kierfeld, Jan

    Biophysical journal

    2014  Band 107, Heft 12, Seite(n) 2860–2871

    Abstract: We formulate and analyze a theoretical model for the regulation of microtubule (MT) polymerization dynamics by the signaling proteins Rac1 and stathmin. In cells, the MT growth rate is inhibited by cytosolic stathmin, which, in turn, is inactivated by ... ...

    Abstract We formulate and analyze a theoretical model for the regulation of microtubule (MT) polymerization dynamics by the signaling proteins Rac1 and stathmin. In cells, the MT growth rate is inhibited by cytosolic stathmin, which, in turn, is inactivated by Rac1. Growing MTs activate Rac1 at the cell edge, which closes a positive feedback loop. We investigate both tubulin sequestering and catastrophe promotion as mechanisms for MT growth inhibition by stathmin. For a homogeneous stathmin concentration in the absence of Rac1, we find a switchlike regulation of the MT mean length by stathmin. For constitutively active Rac1 at the cell edge, stathmin is deactivated locally, which establishes a spatial gradient of active stathmin. In this gradient, we find a stationary bimodal MT-length distribution for both mechanisms of MT growth inhibition by stathmin. One subpopulation of the bimodal length distribution can be identified with fast-growing and long pioneering MTs in the region near the cell edge, which have been observed experimentally. The feedback loop is closed through Rac1 activation by MTs. For tubulin sequestering by stathmin, this establishes a bistable switch with two stable states: one stable state corresponds to upregulated MT mean length and bimodal MT length distributions, i.e., pioneering MTs; the other stable state corresponds to an interrupted feedback with short MTs. Stochastic effects as well as external perturbations can trigger switching events. For catastrophe-promoting stathmin, we do not find bistability.
    Mesh-Begriff(e) Feedback, Physiological ; Microtubules/chemistry ; Microtubules/metabolism ; Models, Biological ; Polymerization ; Stathmin/metabolism ; rac1 GTP-Binding Protein/metabolism
    Chemische Substanzen Stathmin ; rac1 GTP-Binding Protein (EC 3.6.5.2)
    Sprache Englisch
    Erscheinungsdatum 2014-12-16
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218078-9
    ISSN 1542-0086 ; 0006-3495
    ISSN (online) 1542-0086
    ISSN 0006-3495
    DOI 10.1016/j.bpj.2014.10.056
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  8. Artikel ; Online: Exploring risks and benefits of overshooting a 1.5 °C carbon budget over space and time

    Nico Bauer / David P Keller / Julius Garbe / Kristine Karstens / Franziska Piontek / Werner von Bloh / Wim Thiery / Maria Zeitz / Matthias Mengel / Jessica Strefler / Kirsten Thonicke / Ricarda Winkelmann

    Environmental Research Letters, Vol 18, Iss 5, p

    2023  Band 054015

    Abstract: Temperature targets of the Paris Agreement limit global net cumulative emissions to very tight carbon budgets. The possibility to overshoot the budget and offset near-term excess emissions by net-negative emissions is considered economically attractive ... ...

    Abstract Temperature targets of the Paris Agreement limit global net cumulative emissions to very tight carbon budgets. The possibility to overshoot the budget and offset near-term excess emissions by net-negative emissions is considered economically attractive as it eases near-term mitigation pressure. While potential side effects of carbon removal deployment are discussed extensively, the additional climate risks and the impacts and damages have attracted less attention. We link six models for an integrative analysis of the climatic, environmental and socio-economic consequences of temporarily overshooting a carbon budget consistent with the 1.5 °C temperature target along the cause-effect chain from emissions and carbon removals to climate risks and impact. Global climatic indicators such as CO _2 -concentration and mean temperature closely follow the carbon budget overshoot with mid-century peaks of 50 ppmv and 0.35 °C, respectively. Our findings highlight that investigating overshoot scenarios requires temporally and spatially differentiated analysis of climate, environmental and socioeconomic systems. We find persistent and spatially heterogeneous differences in the distribution of carbon across various pools, ocean heat content, sea-level rise as well as economic damages. Moreover, we find that key impacts, including degradation of marine ecosystem, heat wave exposure and economic damages, are more severe in equatorial areas than in higher latitudes, although absolute temperature changes being stronger in higher latitudes. The detrimental effects of a 1.5 °C warming and the additional effects due to overshoots are strongest in non-OECD countries (Organization for Economic Cooperation and Development). Constraining the overshoot inflates CO _2 prices, thus shifting carbon removal towards early afforestation while reducing the total cumulative deployment only slightly, while mitigation costs increase sharply in developing countries. Thus, scenarios with carbon budget overshoots can reverse global mean temperature ...
    Schlagwörter carbon dioxide removal ; mitigation and impacts ; integrated assessment models ; Earth system model of intermediate complexity ; global south ; carbon budget overshoot ; Environmental technology. Sanitary engineering ; TD1-1066 ; Environmental sciences ; GE1-350 ; Science ; Q ; Physics ; QC1-999
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2023-01-01T00:00:00Z
    Verlag IOP Publishing
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  9. Buch ; Online ; Dissertation / Habilitation: Modeling the future resilience of the Greenland Ice Sheet

    Zeitz, Maria [Verfasser] / Winkelmann, Ricarda [Akademischer Betreuer] / Donges, Jonathan [Akademischer Betreuer] / Winkelmann, Ricarda [Gutachter] / Donges, Jonathan [Gutachter] / Karlsson, Nanna B. [Gutachter]

    from the flow of ice to the interplay of feedbacks

    2022  

    Verfasserangabe Maria Zeitz ; Gutachter: Ricarda Winkelmann, Jonathan Donges, Nanna B. Karlsson ; Ricarda Winkelmann, Jonathan Donges
    Schlagwörter Geowissenschaften ; Earth Sciences
    Thema/Rubrik (Code) sg550
    Sprache Englisch
    Verlag Universität Potsdam
    Erscheinungsort Potsdam
    Dokumenttyp Buch ; Online ; Dissertation / Habilitation
    Datenquelle Digitale Dissertationen im Internet

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  10. Artikel ; Online: AI-driven discovery of blood xenobiotic biomarkers in neovascular age-related macular degeneration using iterative random forests.

    Künzel, Steffen E / Frentzel, Dominik P / Flesch, Leonie T M / Knecht, Vitus A / Rübsam, Anne / Dreher, Felix / Schütte, Moritz / Dubrac, Alexandre / Lange, Bodo / Yaspo, Marie-Laure / Lehrach, Hans / Joussen, Antonia M / Zeitz, Oliver

    Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie

    2024  

    Abstract: Purpose: To investigate the xenobiotic profiles of patients with neovascular age-related macular degeneration (nAMD) undergoing anti-vascular endothelial growth factor (anti-VEGF) intravitreal therapy (IVT) to identify biomarkers indicative of clinical ... ...

    Abstract Purpose: To investigate the xenobiotic profiles of patients with neovascular age-related macular degeneration (nAMD) undergoing anti-vascular endothelial growth factor (anti-VEGF) intravitreal therapy (IVT) to identify biomarkers indicative of clinical phenotypes through advanced AI methodologies.
    Methods: In this cross-sectional observational study, we analyzed 156 peripheral blood xenobiotic features in a cohort of 46 nAMD patients stratified by choroidal neovascularization (CNV) control under anti-VEGF IVT. We employed Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) for measurement and leveraged an AI-driven iterative Random Forests (iRF) approach for robust pattern recognition and feature selection, aligning molecular profiles with clinical phenotypes.
    Results: AI-augmented iRF models effectively refined the metabolite spectrum by discarding non-predictive elements. Perfluorooctanesulfonate (PFOS) and Ethyl β-glucopyranoside were identified as significant biomarkers through this process, associated with various clinically relevant phenotypes. Unlike single metabolite classes, drug metabolites were distinctly correlated with subretinal fluid presence.
    Conclusions: This study underscores the enhanced capability of AI, particularly iRF, in dissecting complex metabolomic data to elucidate the xenobiotic landscape of nAMD and environmental impact on the disease. The preliminary biomarkers discovered offer promising directions for personalized treatment strategies, although further validation in broader cohorts is essential for clinical application.
    Sprache Englisch
    Erscheinungsdatum 2024-06-06
    Erscheinungsland Germany
    Dokumenttyp Journal Article
    ZDB-ID 8435-9
    ISSN 1435-702X ; 0721-832X
    ISSN (online) 1435-702X
    ISSN 0721-832X
    DOI 10.1007/s00417-024-06538-2
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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