Geothermal binary power plants that use low-temperature heat sources have gained increasing interest in the recent years due to political efforts to reduce greenhouse gas emissions and the consumption of finite energy resources. The construction of such plants requires large amounts of energy and material. Hence, the question arises if geothermal binary power plants are also environmentally promising from a cradle-to-grave point of view.In this context, a comprehensive Life Cycle Analysis (LCA) on geothermal power production from EGS (enhanced geothermal systems) low-temperature reservoirs is performed. The results of the analysis show that the environmental impacts are very much influenced by the geological conditions that can be obtained at a specific site. At sites with (above-) average geological conditions, geothermal binary power generation can significantly contribute to more sustainable power supply. At sites with less favorable conditions, only certain plant designs can make up for the energy and material input to lock up the geothermal reservoir by the provided energy. The main aspects of environmentally sound plants are enhancement of the reservoir productivity, reliable design of the deep wells and an efficient utilization of the geothermal fluid for net power and district heat production. IntroductionThe use of geothermal energy for electricity and/or heat production has gained increasing interest due to the political goals of reducing greenhouse gas emissions, reducing the The technical requirements to effectively exploit reservoirs with less promising characteristics are quite significant. To tap geological layers with temperatures above 100 °C, deep wells are needed. Drilling and completion of such wells, as well technical measures to enhance geothermal reservoirs in order to obtain higher permeabilities (enhanced geothermal systems, EGS) require large amounts of energy and material. On the surface, the geothermal heat is transferred to a binary conversion cycle (and at some sites additionally to a district heating system). In the binary unit, a working fluid with low boiling point is circulated because the direct use of the geothermal fluid in a power conversion cycle is not efficient from a thermodynamic point of view. Electricity generation using low temperatures heat sources is generally characterized by relatively low conversion efficiencies.Due to the technical challenges associated with the assessment and energetic use of lowtemperature geothermal heat sources, the question arises if the environmental benefit of geothermal energy supply also exists for such reservoirs. Putting this question is furthermore important because most of the low temperature geothermal binary power plants presently need to be subsidized from the public purse due to the still challenging economic performance.In this context, the goal of this paper is it to analyze selected environmental effects of power production from low-temperature geothermal resources based on the Life Cycle Assessment (LCA) methodolog...

Isoprenyl diphosphate synthases (IDSs) produce the ubiquitous branched-chain diphosphates of different lengths that are precursors of all major classes of terpenes. Typically, individual shortchain IDSs (scIDSs) make the C 10 , C 15 , and C 20 isoprenyl diphosphates separately. Here, we report that the product length synthesized by a single scIDS shifts depending on the divalent metal cofactor present. This previously undescribed mechanism of carbon chainlength determination was discovered for a scIDS from juvenile horseradish leaf beetles, Phaedon cochleariae. The recombinant enzyme P. cochleariae isoprenyl diphosphate synthase 1 (PcIDS1) yields 96% C 10 -geranyl diphosphate (GDP) and only 4% C 15 -farnesyl diphosphate (FDP) in the presence of Co 2+ or Mn 2+ as a cofactor, whereas it yields only 18% C 10 GDP but 82% C 15 FDP in the presence of Mg 2+. In reaction with Co 2+ , PcIDS1 has a K m of 11.6 μM for dimethylallyl diphosphate as a cosubstrate and 24.3 μM for GDP. However, with Mg 2+ , PcIDS1 has a K m of 1.18 μM for GDP, suggesting that this substrate is favored by the enzyme under such conditions. RNAi targeting PcIDS1 revealed the participation of this enzyme in the de novo synthesis of defensive monoterpenoids in the beetle larvae. As an FDP synthase, PcIDS1 could be associated with the formation of sesquiterpenes, such as juvenile hormones. Detection of Co , or Mg 2+ in the beetle larvae suggests flux control into C 10 vs. C 15 isoprenoids could be accomplished by these ions in vivo. The dependence of product chain length of scIDSs on metal cofactor identity introduces an additional regulation for these branch point enzymes of terpene metabolism.cobalt | kinetic | prenyltransferase | secretions | silencing

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A major demand on immunotherapy is the direct interference with specific immune cells in vivo. In contrast to antibody-engineered nanoparticles to control dendritic cells function, targeting of T cells for biomedical applications still remains an obstacle as they disclose reduced endocytic activities. Here, by coupling the cytokine interleukin-2 (IL-2) to the surface of hydroxyethyl starch nanocapsules we demonstrated a direct and specifc T cell targeting in vitro and in vivo by IL-2 receptor mediated internalization. For this purpose, defined amounts of azide-functionalized IL-2 were linked to alkyne-functionalized hydroxyethyl starch nanocapsules via copper free click reactions. In combination with validated quantification of the surface-linked IL-2 with anthracen azide this method allowed for engineering IL-2-functionalized nanocapsules for an efficient targeting of human and murine T cell populations with various IL-2 receptor affinities. This nanocapsule-mediated technique is a promising strategy for T cell-based immunotherapies and may be translated to other cytokine-related targeting systems.