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Bioactive secondary metabolites with multiple activities from a fungal endophyte

2016, Bogner, Catherine W., Kamdem, Ramsay S.T., Sichtermann, Gisela, Matthäus, Christian, Hölscher, Dirk, Popp, Jürgen, Proksch, Peter, Grundler, Florian M.W., Schouten, Alexander

In order to replace particularly biohazardous nematocides, there is a strong drive to finding natural product-based alternatives with the aim of containing nematode pests in agriculture. The metabolites produced by the fungal endophyte Fusarium oxysporum 162 when cultivated on rice media were isolated and their structures elucidated. Eleven compounds were obtained, of which six were isolated from a Fusarium spp. for the first time. The three most potent nematode-antagonistic compounds, 4-hydroxybenzoic acid, indole-3-acetic acid (IAA) and gibepyrone D had LC50 values of 104, 117 and 134 Î¼g ml−1, respectively, after 72 h. IAA is a well-known phytohormone that plays a role in triggering plant resistance, thus suggesting a dual activity, either directly, by killing or compromising nematodes, or indirectly, by inducing defence mechanisms against pathogens (nematodes) in plants. Such compounds may serve as important leads in the development of novel, environmental friendly, nematocides.

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Fossil-fueled development (SSP5): An energy and resource intensive scenario for the 21st century

2016, Kriegler, Elmar, Bauer, Nico, Popp, Alexander, Humpenöder, Florian, Leimbach, Marian, Strefler, Jessica, Baumstark, Lavinia, Bodirsky, Benjamin Leon, Hilaire, Jérôme, Klein, David, Mouratiadou, Ioanna, Weindl, Isabelle, Bertram, Christoph, Dietrich, Jan-Philipp, Luderer, Gunnar, Pehl, Michaja, Pietzcker, Robert, Piontek, Franziska, Lotze-Campen, Hermann, Biewald, Anne, Bonsch, Markus, Giannousakis, Anastasis, Kreidenweis, Ulrich, Müller, Christoph, Rolinski, Susanne, Schultes, Anselm, Schwanitz, Jana, Stevanovic, Miodrag, Calvin, Katherine, Emmerling, Johannes, Fujimori, Shinichiro, Edenhofer, Ottmar

This paper presents a set of energy and resource intensive scenarios based on the concept of Shared Socio-Economic Pathways (SSPs). The scenario family is characterized by rapid and fossil-fueled development with high socio-economic challenges to mitigation and low socio-economic challenges to adaptation (SSP5). A special focus is placed on the SSP5 marker scenario developed by the REMIND-MAgPIE integrated assessment modeling framework. The SSP5 baseline scenarios exhibit very high levels of fossil fuel use, up to a doubling of global food demand, and up to a tripling of energy demand and greenhouse gas emissions over the course of the century, marking the upper end of the scenario literature in several dimensions. These scenarios are currently the only SSP scenarios that result in a radiative forcing pathway as high as the highest Representative Concentration Pathway (RCP8.5). This paper further investigates the direct impact of mitigation policies on the SSP5 energy, land and emissions dynamics confirming high socio-economic challenges to mitigation in SSP5. Nonetheless, mitigation policies reaching climate forcing levels as low as in the lowest Representative Concentration Pathway (RCP2.6) are accessible in SSP5. The SSP5 scenarios presented in this paper aim to provide useful reference points for future climate change, climate impact, adaption and mitigation analysis, and broader questions of sustainable development.

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Future air pollution in the Shared Socio-economic Pathways

2016, Rao, Shilpa, Klimont, Zbigniew, Smith, Steven J., Van Dingenen, Rita, Dentener, Frank, Bouwman, Lex, Riahi, Keywan, Amann, Markus, Bodirsky, Benjamin Leon, van Vuuren, Detlef P., Aleluia Reis, Lara, Calvin, Katherine, Drouet, Laurent, Fricko, Oliver, Fujimori, Shinichiro, Gernaat, David, Havlik, Petr, Harmsen, Mathijs, Hasegawa, Tomoko, Heyes, Chris, Hilaire, Jérôme, Luderer, Gunnar, Masui, Toshihiko, Stehfest, Elke, Strefler, Jessica, van der Sluis, Sietske, Tavoni, Massimo

Emissions of air pollutants such as sulfur and nitrogen oxides and particulates have significant health impacts as well as effects on natural and anthropogenic ecosystems. These same emissions also can change atmospheric chemistry and the planetary energy balance, thereby impacting global and regional climate. Long-term scenarios for air pollutant emissions are needed as inputs to global climate and chemistry models, and for analysis linking air pollutant impacts across sectors. In this paper we present methodology and results for air pollutant emissions in Shared Socioeconomic Pathways (SSP) scenarios. We first present a set of three air pollution narratives that describe high, central, and low pollution control ambitions over the 21st century. These narratives are then translated into quantitative guidance for use in integrated assessment models. The resulting pollutant emission trajectories under the SSP scenarios cover a wider range than the scenarios used in previous international climate model comparisons. In the SSP3 and SSP4 scenarios, where economic, institutional and technological limitations slow air quality improvements, global pollutant emissions over the 21st century can be comparable to current levels. Pollutant emissions in the SSP1 scenarios fall to low levels due to the assumption of technological advances and successful global action to control emissions.

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Oberflächenmorphologie von Arzneistoffpartikeln - Ein optisch evaluierbares Kriterium für die Auflösungsgeschwindigkeit

2002, Diebold, Steffen M.

Für die Auflösungsgeschwindigkeit von schwer wasserlöslichen Arzneistoffpartikeln spielt die Hydrodynamik an den Partikel-Oberflächen eine große Rolle. Diese ist ihrerseits beeinflußt von der Geometrie und der Oberflächenmorphologie der Partikel. In dieser Arbeit wurde gezeigt, dass sich zur Charakterisierung dieser Parameter die Rasterelektronenmikroskopie (SEM) auch für die Untersuchung von Arzneistoffen gut eignet. Am Beispiel von Felodipin-Kristallen wurde nachgewiesen, dass reale Arzneistoffpulver auch an scheinbar „glatten“ Oberflächen Protrusionen, Kanten und Kavitäten aufweisen. Deren Größenordnungen lassen sich mit Hilfe der Elektronenmikroskopie abschätzen. Die Oberflächenmorphologie von Arzneistoffpartikeln ist ein Kriterium für die Auflösungsgeschwindigkeit oral verabreichter Arzneistoffe. Die Rasterelektronenmikroskopie leistet dabei wertvolle Dienste zur Charakterisierung der Oberflächen von Arzneistoffpartikeln.

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Energy, land-use and greenhouse gas emissions trajectories under a green growth paradigm

2016, van Vuuren, Detlef P., Stehfest, Elke, Gernaat, David E.H.J., Doelman, Jonathan C., van den Berg, Maarten, Harmsen, Mathijs, de Boer, Harmen Sytze, Bouwman, Lex F., Daioglou, Vassilis, Edelenbosch, Oreane Y., Girod, Bastien, Kram, Tom, Lassaletta, Luis, Lucas, Paul L., van Meijl, Hans, Müller, Christoph, van Ruijven, Bas J., van der Sluis, Sietske, Tabeau, Andrzej

This paper describes the possible developments in global energy use and production, land use, emissions and climate changes following the SSP1 storyline, a development consistent with the green growth (or sustainable development) paradigm (a more inclusive development respecting environmental boundaries). The results are based on the implementation using the IMAGE 3.0 integrated assessment model and are compared with a) other IMAGE implementations of the SSPs (SSP2 and SSP3) and b) the SSP1 implementation of other integrated assessment models. The results show that a combination of resource efficiency, preferences for sustainable production methods and investment in human development could lead to a strong transition towards a more renewable energy supply, less land use and lower anthropogenic greenhouse gas emissions in 2100 than in 2010, even in the absence of explicit climate policies. At the same time, climate policy would still be needed to reduce emissions further, in order to reduce the projected increase of global mean temperature from 3 Â°C (SSP1 reference scenario) to 2 or 1.5 Â°C (in line with current policy targets). The SSP1 storyline could be a basis for further discussions on how climate policy can be combined with achieving other societal goals.

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Future growth patterns of world regions – A GDP scenario approach

2015, Leimbach, Marian, Kriegler, Elmar, Roming, Niklas, Schwanitz, Jana

Global GDP projections for the 21st century are needed for the exploration of long-term global environmental problems, in particular climate change. Greenhouse gas emissions as well as climate change mitigation and adaption capacities strongly depend on growth of per capita income. However, long-term economic projections are highly uncertain. This paper provides five new long-term economic scenarios as part of the newly developed shared socio-economic pathways (SSPs) which represent a set of widely diverging narratives. A method of GDP scenario building is presented that is based on assumptions about technological progress, and human and physical capital formation as major drivers of long-term GDP per capita growth. The impact of these drivers differs significantly between different shared socio-economic pathways and is traced back to the underlying narratives and the associated population and education scenarios. In a highly fragmented world, technological and knowledge spillovers are low. Hence, the growth impact of technological progress and human capital is comparatively low, and per capita income diverges between world regions. These factors play a much larger role in globalization scenarios, leading to higher economic growth and stronger convergence between world regions. At the global average, per capita GDP is projected to grow annually in a range between 1.0% (SSP3) and 2.8% (SSP5) from 2010 to 2100. While this covers a large portion of variety in future global economic growth projections, plausible lower and higher growth projections may still be conceivable. The GDP projections are put into the context of historic patterns of economic growth (stylized facts), and their sensitivity to key assumptions is explored.

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Non-thermal plasma activates human keratinocytes by stimulation of antioxidant and phase II pathways

2015, Schmidt, Anke, Dietrich, Stephan, Steuer, Anna, Weltmann, Klaus-Dieter, von Woedtke, Thomas, Masur, Kai, Wende, Kristian

Non-thermal atmospheric pressure plasma provides a novel therapeutic opportunity to control redox-based processes, e.g. wound healing, cancer, and inflammatory diseases. By spatial and time-resolved delivery of reactive oxygen and nitrogen species, it allows stimulation or inhibition of cellular processes in biological systems. Our data show that both gene and protein expression is highly affected by non-thermal plasma. Nuclear factor erythroid-related factor 2 (NRF2) and phase II enzyme pathway components were found to act as key controllers orchestrating the cellular response in keratinocytes. Additionally, glutathione metabolism, which is a marker for NRF2-related signaling events, was affected. Among the most robustly increased genes and proteins, heme oxygenase 1, NADPH-quinone oxidoreductase 1, and growth factors were found. The roles of NRF2 targets, investigated by siRNA silencing, revealed that NRF2 acts as an important switch for sensing oxidative stress events. Moreover, the influence of non-thermal plasma on the NRF2 pathway prepares cells against exogenic noxae and increases their resilience against oxidative species. Via paracrine mechanisms, distant cells benefit from cell-cell communication. The finding that non-thermal plasma triggers hormesis-like processes in keratinocytes facilitates the understanding of plasma-tissue interaction and its clinical application.

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The Shared Socioeconomic Pathways and their energy, land use, and greenhouse gas emissions implications: An overview

2016, Riahi, Keywan, van Vuuren, Detlef P., Kriegler, Elmar, Edmonds, Jae, O’Neill, Brian C., Fujimori, Shinichiro, Bauer, Nico, Calvin, Katherine, Dellink, Rob, Fricko, Oliver, Lutz, Wolfgang, Popp, Alexander, Crespo Cuaresma, Jesus, KC, Samir, Leimbach, Marian, Jiang, Leiwen, Kram, Tom, Rao, Shilpa, Emmerling, Johannes, Ebi, Kristie, Hasegawa, Tomoko, Havlik, Petr, Humpenöder, Florian, Aleluia Da Silva, Lara, Smith, Steve, Stehfest, Elke, Bosetti, Valentina, Eom, Jiyong, Gernaat, David, Masui, Toshihiko, Rogelj, Joeri, Strefler, Jessica, Drouet, Laurent, Krey, Volker, Luderer, Gunnar, Harmsen, Mathijs, Takahashi, Kiyoshi, Baumstark, Lavinia, Doelman, Jonathan C., Kainuma, Mikiko, Klimont, Zbigniew, Marangoni, Giacomo, Lotze-Campen, Hermann, Obersteiner, Michael, Tabeau, Andrzej, Tavoni, Massimo

This paper presents the overview of the Shared Socioeconomic Pathways (SSPs) and their energy, land use, and emissions implications. The SSPs are part of a new scenario framework, established by the climate change research community in order to facilitate the integrated analysis of future climate impacts, vulnerabilities, adaptation, and mitigation. The pathways were developed over the last years as a joint community effort and describe plausible major global developments that together would lead in the future to different challenges for mitigation and adaptation to climate change. The SSPs are based on five narratives describing alternative socio-economic developments, including sustainable development, regional rivalry, inequality, fossil-fueled development, and middle-of-the-road development. The long-term demographic and economic projections of the SSPs depict a wide uncertainty range consistent with the scenario literature. A multi-model approach was used for the elaboration of the energy, land-use and the emissions trajectories of SSP-based scenarios. The baseline scenarios lead to global energy consumption of 400–1200 EJ in 2100, and feature vastly different land-use dynamics, ranging from a possible reduction in cropland area up to a massive expansion by more than 700 million hectares by 2100. The associated annual CO2 emissions of the baseline scenarios range from about 25 GtCO2 to more than 120 GtCO2 per year by 2100. With respect to mitigation, we find that associated costs strongly depend on three factors: (1) the policy assumptions, (2) the socio-economic narrative, and (3) the stringency of the target. The carbon price for reaching the target of 2.6 W/m2 that is consistent with a temperature change limit of 2 Â°C, differs in our analysis thus by about a factor of three across the SSP marker scenarios. Moreover, many models could not reach this target from the SSPs with high mitigation challenges. While the SSPs were designed to represent different mitigation and adaptation challenges, the resulting narratives and quantifications span a wide range of different futures broadly representative of the current literature. This allows their subsequent use and development in new assessments and research projects. Critical next steps for the community scenario process will, among others, involve regional and sectoral extensions, further elaboration of the adaptation and impacts dimension, as well as employing the SSP scenarios with the new generation of earth system models as part of the 6th climate model intercomparison project (CMIP6).

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Applications of synthetic polymers in clinical medicine

2015, Maitz, Manfred F.

Multiple biological, synthetic and hybrid polymers are used for multiple medical applications. A wide range of different polymers is available, and they have further the advantage to be tunable in physical, chemical and biological properties in a wide range to match the requirements of specific applications. This review gives a brief overview about the introduction and developments of polymers in medicine in general, addressing first stable polymers, then polymers with degradability as a first biological function, followed by various other functional and responsive polymers. It is shown up that biomedical polymers comprise not only bulk materials, but also coatings and pharmaceutical nano-carriers for drugs. There is subsequently an overview of the most frequently used polymer classes. The main body of the review then is structured according to the medical applications, where key requirements of the applications and the currently used polymer solutions are indicated.