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101.
Tarek Abu‐Husein Swen Schuster Martin Kind Tobias Santowski Adrian Wiesner Ryan Chiechi Egbert Zojer Andreas Terfort Michael Zharnikov 《Advanced functional materials》2015,25(25):3943-3957
Using a representative model system, here electronic and structural properties of aromatic self‐assembled monolayers (SAMs) are described that contain an embedded, dipolar group. As polar unit, pyrimidine is used, with its orientation in the molecular backbone and, consequently, the direction of the embedded dipole moment being varied. The electronic and structural properties of these embedded‐dipole SAMs are thoroughly analyzed using a number of complementary characterization techniques combined with quantum‐mechanical modeling. It is shown that such mid‐chain‐substituted monolayers are highly interesting from both fundamental and application viewpoints, as the dipolar groups are found to induce a potential discontinuity inside the monolayer, electrostatically shifting the core‐level energies in the regions above and below the dipoles relative to one another. These SAMs also allow for tuning the substrate work function in a controlled manner independent of the docking chemistry and, most importantly, without modifying the SAM‐ambient interface. 相似文献
102.
Advances in computation challenge established design approaches in architecture through a much deeper integration of form generation and materialisation. Tobias Schwinn , Research Associate at the Institute for Computational Design (ICD), University of Stuttgart, and Guest-Editor Achim Menges , Director of the ICD, introduce how the potentials and constraints of robotic fabrication can now be explored as generative drivers in agent-based design. This enables architectural innovation in unison with fabricability, structural capacity and spatial performance, as demonstrated by the Landesgartenschau Exhibition Hall in Schwäbisch Gmu"nd, Germany, the world's first building with a robotically fabricated segmented timber shell as its primary structure. 相似文献
103.
104.
Base‐catalyzed transesterification of fats and oils with primary alcohols in discontinuous operation is an established batch process for the biodiesel production. However, the application of microreaction technology and continuous flow process lead to an increase of process intensification. The ethanol/soy bean oil ratio at low flow rates as well as the reactor geometry have the most evident effects on the fatty acid ethyl ester yield of KOH‐catalyzed ethanolysis of soy bean oil in microreactors. The influence of the catalyst concentration is of a lower importance. 相似文献
105.
Identification and Structure–Activity Relationship Studies of Small‐Molecule Inhibitors of the Methyllysine Reader Protein Spindlin1 下载免费PDF全文
Dr. Dina Robaa Dr. Tobias Wagner Chiara Luise Dr. Luca Carlino Joel McMillan Dr. Ralf Flaig Prof. Dr. Roland Schüle Prof. Dr. Manfred Jung Prof. Dr. Wolfgang Sippl 《ChemMedChem》2016,11(20):2327-2338
The methyllysine reader protein Spindlin1 has been implicated in the tumorigenesis of several types of cancer and may be an attractive novel therapeutic target. Small‐molecule inhibitors of Spindlin1 should be valuable as chemical probes as well as potential new therapeutics. We applied an iterative virtual screening campaign, encompassing structure‐ and ligand‐based approaches, to identify potential Spindlin1 inhibitors from databases of commercially available compounds. Our in silico studies coupled with in vitro testing were successful in identifying novel Spindlin1 inhibitors. Several 4‐aminoquinazoline and quinazolinethione derivatives were among the active hit compounds, which indicated that these scaffolds represent promising lead structures for the development of Spindlin1 inhibitors. Subsequent lead optimization studies were hence carried out, and numerous derivatives of both lead scaffolds were synthesized. This resulted in the discovery of novel inhibitors of Spindlin1 and helped explore the structure–activity relationships of these inhibitor series. 相似文献
106.
A Catalytic Nanoreactor Based on in Vivo Encapsulation of Multiple Enzymes in an Engineered Protein Nanocompartment 下载免费PDF全文
Dr. Tobias W. Giessen Prof. Dr. Pamela A. Silver 《Chembiochem : a European journal of chemical biology》2016,17(20):1931-1935
Bacterial protein compartments concentrate and sequester enzymes, thereby regulating biochemical reactions. Here, we generated a new functional nanocompartment in Escherichia coli by engineering the MS2 phage capsid protein to encapsulate multiple cargo proteins. Sequestration of multiple proteins in MS2‐based capsids was achieved by SpyTag/SpyCatcher protein fusions that covalently crosslinked with the interior surface of the capsid. Further, the functional two‐enzyme indigo biosynthetic pathway could be targeted to the engineered capsids, leading to a 60 % increase in indigo production in vivo. The enzyme‐loaded particles could be purified in their active form and showed enhanced long‐term stability in vitro (about 95 % activity after seven days) compared with free enzymes (about 5 % activity after seven days). In summary, this engineered in vivo encapsulation system provides a simple and versatile way for generating highly stable multi‐enzyme nanoreactors for in vivo and in vitro applications. 相似文献
107.
108.
Tobias Schneider Lars Wietschel Denny Schüppel Jonas Riesner Kevin Konrad Andrea Thorenz Axel Tuma Dietmar Koch 《International Journal of Applied Ceramic Technology》2022,19(6):3247-3254
Over the past 40 years, development of Ceramic Matrix Composites (CMCs) has focused mainly on the improvement of material performance and optimization of cost-efficient production routes. Recently, more fields of application have opened up for CMCs, in which environmental impacts are relevant. These impacts have barely been investigated so far but receive growing interest due to increasing awareness of the environmental consequences. Our innovative approach frames material properties in relation to environmental impacts (e.g., global warming potential in CO2 emission) by varying process parameters to balance optimum performance against environmental considerations. First, the process of wet filament winding has been investigated up to the Carbon Fiber Reinforced Plastic (CFRP) state by changing both the curing and tempering temperatures. During the production of CFRP plates, mass and energy flows were tracked in each step. Three point-bending and interlaminar shear tests have been performed on the resulting samples to identify basic mechanical properties. The environmental impacts are determined by a cradle-to-gate Life Cycle Assessment (LCA), using the software SimaPro. The resulting tradeoffs between mechanical properties and environmental impacts show nonlinear behavior, thus revealing optimum points above which improved mechanical properties are associated with significantly higher CO2 emissions. 相似文献
109.
Annika Linke Tobias Linke Reinhard Kohlus 《European Journal of Lipid Science and Technology》2020,122(8)
Microencapsulation aims to protect polyunsaturated fatty acids against oxidation by embedding oil droplets in a solid matrix. In such a system the internal (dissolved and entrapped) and external (in the environment) oxygen can be differentiated. The study aims to quantify the impact of both oxygen sources on the oxidation of microencapsulated fish oil. The impact of the solubilized oxygen in bulk fish oil is investigated by saturating the oil with nitrogen, synthetic air, and pure oxygen. Even though more dissolved oxygen results in more oxidation products, the difference between the oxidation of the nitrogen and air saturated oil is significant but low. For encapsulated fish oil powders, the internal oxygen is modified by preparing oil‐in‐water emulsions under atmospheric and inert conditions. The feed is atomized and spray dried with either nitrogen or air. Powders are stored under vacuum and in vials and the hydroperoxides and anisidine value are determined in the total‐ and encapsulated oil. The internal oxygen has a minor impact, whereas the external oxygen is the main determinant for autoxidation. Apart from oxidizing the non‐encapsulated oil, the external O2 penetrates into the particle and reacts with the encapsulated oil. Practical Applications: Comparing the contribution of the internal and external oxygen to the oxidative stability shows that the internal O2 plays a minor role and can be neglected. This means that the emulsion preparation as well as the spray drying process can be conducted under ambient conditions. An inert production is not extending the shelf life significantly as long as the external O2 determines oxidation. The focus should be on optimizing the diffusion barrier properties of the wall matrix to reduce the penetration of the external oxygen into the particle system. Alternatively, packaging solution reducing the external O2 will extend the shelf life of the microencapsulated oil. 相似文献
110.
Stephan W. Reinhold Thomas Scherl Benjamin Stölcker Tobias Bergler Ute Hoffmann Christian Weingart Miriam C. Banas Dmitrij Kollins Martin C. Kammerl Bernd Krüger Bernhard Kaess Bernhard K. Krämer Bernhard Banas 《Lipids》2013,48(2):167-175
Acute transplant rejection is the leading cause of graft loss in the first months after kidney transplantation. Lipoxygenase products mediate pro- and anti-inflammatory actions and thus we aimed to correlate the histological reports of renal transplant biopsies with urinary lipoxygenase products concentrations to evaluate their role as a diagnostic marker. This study included a total of 34 kidney transplant recipients: 17 with an acute transplant rejection and 17 controls. LTE4, LTB4, 12-HETE and 15-HETE concentrations were measured by enzyme immunoassay. Urinary lipoxygenase product concentrations were not significantly changed during an acute allograft rejection. Nevertheless, LTB4 concentrations correlated significantly with the body temperature (P ≤ 0.05) 3 months after transplantation, and 12- and 15-HETE concentrations correlated significantly with renal function (P ≤ 0.05) 2 weeks after transplantation. In conclusion, our data show a correlation for LTB4 with the body temperature 3 months after transplantation and urinary 12- and 15-HETE concentrations correlate positively with elevated serum creatinine concentrations but do not predict acute allograft rejection. 相似文献