Bio-Inspired Amphiphilic Block-Copolymers Based on Synthetic Glycopolymer and Poly(Amino Acid) as Potential Drug Delivery Systems

In this work, a method to prepare hybrid amphiphilic block copolymers consisting of biocompatible synthetic glycopolymer with non-degradable backbone and biodegradable poly(amino acid) (PAA) was developed. The glycopolymer, poly(2-deoxy-2-methacrylamido-D-glucose) (PMAG), was synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization. Two methods for modifying the terminal dithiobenzoate-group of PMAG was investigated to obtain the macroinitiator bearing a primary aliphatic amino group, which is required for ring-opening polymerization of N-carboxyanhydrides of hydrophobic α-amino acids. The synthesized amphiphilic block copolymers were carefully analyzed using a set of different physico-chemical methods to establish their composition and molecular weight. The developed amphiphilic copolymers tended to self-assemble in nanoparticles of different morphology that depended on the nature of the hydrophobic amino acid present in the copolymer. The hydrodynamic diameter, morphology, and cytotoxicity of polymer particles based on PMAG-b-PAA were evaluated using dynamic light scattering (DLS) and transmission electron microscopy (TEM), as well as CellTiter-Blue (CTB) assay, respectively. The redox-responsive properties of nanoparticles were evaluated in the presence of glutathione taken at different concentrations. Moreover, the encapsulation of paclitaxel into PMAG-b-PAA particles and their cytotoxicity on human lung carcinoma cells (A549) and human breast adenocarcinoma cells (MCF-7) were studied

Few-cycle laser driven reaction nanoscopy on aerosolized silica nanoparticles

Nanoparticles offer unique properties as photocatalysts with large surface areas. Under irradiation with light, the associated near-fields can induce, enhance, and control molecular adsorbate reactions on the nanoscale. So far, however, there is no simple method available to spatially resolve the near-field induced reaction yield on the surface of nanoparticles. Here we close this gap by introducing reaction nanoscopy based on three-dimensional momentum-resolved photoionization. The technique is demonstrated for the spatially selective proton generation in few-cycle laser-induced dissociative ionization of ethanol and water on SiO2 nanoparticles, resolving a pronounced variation across the particle surface. The results are modeled and reproduced qualitatively by electrostatic and quasi-classical mean-field Mie Monte-Carlo (M3C) calculations. Reaction nanoscopy is suited for a wide range of isolated nanosystems and can provide spatially resolved ultrafast reaction dynamics on nanoparticles, clusters, and droplets

Exact solutions for interacting boson systems under rotation

We study a class of interacting, harmonically trapped boson systems at angular momentum L. The Hamiltonian leaves a L-dimensional subspace invariant, and this permits an explicit solution of several eigenstates and energies for a wide class of two-body interactionsComment: 8 pages, error corrected (concerns generalization of subspace structure

Few-cycle laser driven reaction nanoscopy on aerosolized silica nanoparticles

Nanoparticles offer unique properties as photocatalysts with large surface areas. Under irradiation with light, the associated near-fields can induce, enhance, and control molecular adsorbate reactions on the nanoscale. So far, however, there is no simple method available to spatially resolve the near-field induced reaction yield on the surface of nanoparticles. Here we close this gap by introducing reaction nanoscopy based on three-dimensional momentum-resolved photoionization. The technique is demonstrated for the spatially selective proton generation in few-cycle laser-induced dissociative ionization of ethanol and water on SiO2 nanoparticles, resolving a pronounced variation across the particle surface. The results are modeled and reproduced qualitatively by electrostatic and quasi-classical mean-field Mie Monte-Carlo (M3C) calculations. Reaction nanoscopy is suited for a wide range of isolated nanosystems and can provide spatially resolved ultrafast reaction dynamics on nanoparticles, clusters, and droplets

The individual relationship between atrial fibrillation sources from CARTOFINDER mapping and atrial cardiomyopathy: the catch me if you can trial

Background Targeting individual sources identified during atrial fibrillation (AF) has been used as an ablation strategy with varying results. Objective Aim of this study was to evaluate the relationship between regions of interest (ROIs) from CARTOFINDER (CF) mapping and atrial cardiomyopathy from late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR). Methods Twenty consecutive patients underwent index catheter ablation for persistent AF (PERS AF). Pre-processed LGE CMR images were merged with the results from CF mapping to visualize harboring regions for focal and rotational activities. Atrial cardiomyopathy was classified based on the four Utah stages. Results Procedural success was achieved in all patients (n = 20, 100%). LGE CMR revealed an intermediate amount of 21.41% ± 6.32% for LA fibrosis. ROIs were identified in all patients (mean no ROIs per patient n = 416.45 ± 204.57). A tendency towards a positive correlation between the total amount of atrial cardiomyopathy and the total number of ROIs per patient (regression coefficient, β = 10.86, p = .15) was observed. The degree of fibrosis and the presence of ROIs per segment showed no consistent spatial correlation (posterior: β = 0.36, p-value (p) = .24; anterior: β = −0.08, p = .54; lateral: β = 0.31, p = 39; septal: β = −0.12; p = .66; right PVs: β = 0.34, p = .27; left PVs: β = 0.07, p = .79; LAA: β = −0.91, p = .12). 12 months AF-free survival was 70% (n = 14) after ablation. Conclusion The presence of ROIs from CF mapping was not directly associated with the extent and location of fibrosis. Further studies evaluating the relationship between focal and rotational activity and atrial cardiomyopathy are mandatory

All-optical spatio-temporal control of electron emission from SiO2 nanospheres with femtosecond two-color laser fields

Field localization by nanostructures illuminated with laser pulses of well-defined waveform enables spatio-temporal tailoring of the near-fields for sub-cycle control of electron dynamics at the nanoscale. Here, we apply intense linearly-polarized two-color laser pulses for all-optical control of the highest energy electron emission from SiO2 nanoparticles. For the size regime where light propagation effects become important, we demonstrate the possibility to control the preferential emission angle of a considerable fraction of the fastest electrons by varying the relative phase of the two-color field. Trajectory based semi-classical simulations show that for the investigated nanoparticle size range the directional steering can be attributed to the two-color effect on the electron trajectories, while the accompanied modification of the spatial distribution of the ionization rate on the nanoparticle surface has only a minor effect. © 2019 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaf

Quenching of material dependence in few-cycle driven electron acceleration from nanoparticles under many-particle charge interaction

The excitation of nanoscale near-fields with ultrashort and intense laser pulses of well-defined waveform enables strongly spatially and temporally localized electron emission, opening up the possibility for the generation of attosecond electron pulses. Here, we investigate the electron photoemission from isolated nanoparticles of different materials in few-cycle laser fields at intensities where the Coulomb field of the ionized electrons and residual ions significantly contribute to the electron acceleration process. The dependences of the electron cut-off energy on the material’s dielectric properties and electron binding energy are investigated systematically in both experiments and semi-classical simulations. We find that for sufficiently high near-field intensities the material dependence of the acceleration in the enhanced near-fields is quenched by many-particle charge-interaction

Crop rotations with and without legumes: a review

Leguminosen sind im ökologischen Landbau aufgrund ihrer Fähigkeit zur Luftstickstofffixierung unverzichtbar für die Stickstoffversorgung der Ackerkulturen und die Proteinversorgung der Nutztiere. Im konventionellen Anbau bieten Leguminosen die Möglichkeit, die häufig getreideintensiven Fruchtfolgen aufzulockern. Eine der wichtigsten Wirkungen dieses Break-crop-Effekts ist das Durchbrechen des Lebenszyklus von fruchtartenspezifischen Pathogenen und der damit verbundenen Einsparung von Pflanzenschutzmitteln. Die vorliegende Übersichtsarbeit stellt den derzeitigen Stand des Wissens zu Fruchtfolgen mit und ohne Leguminosen zusammen. Dabei werden ackerbauliche, ökologische und ökonomische Wirkungen des Anbaus groß- und kleinkörnig Leguminosenarten als Haupt- oder Zwischenfrüchte bzw. Unter­saaten oder als Komponenten in Gemengen dar­gestellt und bewertet. Der Schwerpunkt liegt dabei auf relevanten Publikationen in wissenschaftlichen Journalen sowie Praxis- und Forschungsberichten der Jahre 2010 – 2020 die in Deutschland oder vergleichbaren klimatischen Bedingungen durchgeführt wurden. Abschließend wird daraus der notwendige Forschungsbedarf für die Themenbereiche Pflanzenbau (konventionell und ökologisch), Pflanzenschutz, Ökonomie, Ökologie und Klimaschutz abgeleitet.In organic farming, legumes are indispensable for the nitro­gen supply of arable crops and the protein supply of livestock due to their ability to fix atmospheric nitrogen. In conventional farming, legumes offer the potential to break the often cereal-intensive crop rotations. One of the most important consequences of the break-crop effect is the interruption of the life cycle of crop-specific pathogens and the associated savings of pesticides. This review summarizes the current state of knowledge on crop rotations with and without legumes. It presents and evaluates the agronomic, ecological and economic effects of the cultivation of large- and small-seeded legume species as main or catch crops, when undersown in other crops, or used as components in mixtures. The focus is on relevant publications in scientific journals as well as practice and research reports published between 2010 and 2020 which were carried out in Germany or under comparable climatic conditions. Finally, essential research needs in the areas of crop production (conventional and organic), crop protection, economics, ecology, and climate protection are identified

25 Jahre Kommunikationswissenschaft. Festschrift

Festschrift zum 25-jährigen Bestehen des Fachs Kommunikationswissenschaft an der Otto-Friedrich-Universität Bamberg mit Texten von: Rudolf Stöber, Anna Maria Theis-Berglmair, Manfred Rühl, Thomas Gruber, Gero Himmelsbach und Peter Gregor zur Geschichte des Fachs, des Rundfunks, des Medienrechts und der PR. Grußworte von Godehard Ruppert und Friedhelm Marx. Mit einer Chronik des Fachs, einer Übersicht aktueller Publikationen und einer Übersicht von Abschlussarbeiten der Wintersemester 2005/06 bis Wintersemester 2007/08. Entstanden in der Übung Projektmanagement im Wintersemester 2007/08

αβ T-cell receptors from multiple sclerosis brain lesions show MAIT cell–related features

Objectives: To characterize phenotypes of T cells that accumulated in multiple sclerosis (MS) lesions, to compare the lesional T-cell receptor (TCR) repertoire of T-cell subsets to peripheral blood, and to identify paired α and β chains from single CD8+ T cells from an index patient who we followed for 18 years. Methods: We combined immunohistochemistry, laser microdissection, and single-cell multiplex PCR to characterize T-cell subtypes and identify paired TCRα and TCRβ chains from individual brain-infiltrating T cells in frozen brain sections. The lesional and peripheral TCR repertoires were analyzed by pyrosequencing. Results: We found that a TCR Vβ1+ T-cell population that was strikingly expanded in active brain lesions at clinical onset comprises several subclones expressing distinct yet closely related Vα7.2+ α chains, including a canonical Vα7.2-Jα33 chain of mucosal-associated invariant T (MAIT) cells. Three other α chains bear striking similarities in their antigen-recognizing, hypervariable complementarity determining region 3. Longitudinal repertoire studies revealed that the TCR chains that were massively expanded in brain at onset persisted for several years in blood or CSF but subsequently disappeared except for the canonical Vα7.2+ MAIT cell and a few other TCR sequences that were still detectable in blood after 18 years. Conclusions: Our observation that a massively expanded TCR Vβ1-Jβ2.3 chain paired with distinct yet closely related canonical or atypical MAIT cell–related α chains strongly points to an antigen-driven process in early active MS brain lesions