Publikationen Natur- und Ingenieurwissenschaften 2014

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Originalarbeiten in wissenschaftlichen Fachzeitschriften

Jahre: 2014

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2014

Lorenz R, Bock J, Barker A, von Knobelsdorff-Brenkenhoff F, Wallis W, Korvink J, Bissell M, Schulz-Menger J, Markl M
4D Flow Magnetic Resonance Imaging in Bicuspid Aortic Valve Disease Demonstrates Altered Distribution of Aortic Blood Flow Helicity
2014 MAGNETIC RESONANCE IN MEDICINE, Band: 71, Nummer: 4, Seiten: 1542 - 1553
KurzfassungPurposeChanges in aortic geometry or presence of aortic valve (AoV) disease can result in substantially altered aortic hemodynamics. Dilatation of the ascending aorta or AoV abnormalities can result in an increase in helical flow. Methods4D flow magnetic resonance imaging was used to test the feasibility of quantitative helicity analysis using equidistantly distributed 2D planes along the entire aorta. The evaluation of the method included three parts: (1) the quantification of helicity in 12 healthy subjects, (2) an evaluation of observer variability and test-retest reliability, and (3) the quantification of helical flow in 16 patients with congenitally altered bicuspid AoVs. ResultsHelicity quantification in healthy subjects revealed consistent directions of flow rotation along the entire aorta with high clockwise helicity in the aortic arch and an opposite rotation sense in the ascending and descending aorta. The results demonstrated good scan-rescan and inter- and intraobserver agreement of the helicity parameters. Helicity quantification in patients revealed a significant increase in absolute peak relative helicity during systole and a considerably greater heterogeneous distribution of mean helicity in the aorta. ConclusionThe method has the potential to serve as a reference distribution for comparisons of helical flow between healthy subjects and patients or between different patient groups. Magn Reson Med 71:1542-1553, 2014. (c) 2013 Wiley Periodicals, Inc.
Rohde M, Muller LO, Himmel D, Scherer H, Krossing I
A Janus-headed Lewis superacid: simple access to, and first application of Me3Si-F-Al(OR(F))3.
2014 Chem-eur J, Band: 20, Nummer: 5, Seiten: 1218 - 1222
Cubukcu A, Romero D, Urban G
A dynamic thermal flow sensor for simultaneous measurement of thermal conductivity and flow velocity of gases
2014 SENSORS AND ACTUATORS A-PHYSICAL, Band: 208, Seiten: 73 - 87
KurzfassungThrough finite element modeling and experiments, we describe individual influences of gas flow velocity (v) and thermal conductivity (lambda) on temperature amplitude and phase measurements from a dynamic MEMS thermal flow sensor that employs AC heating at 200 Hz. We further describe the relationships among the temperature phase, time-of-flight, and time-of-diffusion proposing a new boundary layer definition based on the existing flow and thermal boundary layer theories. The sensor has five primary thermistors made of amorphous germanium for high sensitivity. Four of these are symmetrically distributed around four central heater elements on a thermally isolating diaphragm where the fifth is in the center. Simulations and experimental results show that phase shifts (time lags) of temperature between thermistors primarily depend on lambda, and negligibly on v below a velocity limit. Simulation results also suggest that the influences of density (rho) and specific heat capacity (c(p)) on these phase shifts are relatively small or even negligible. Thus, lambda can be accurately determined independent of the flow velocity for gases of similar rho.c(p) product, up to 1 m/s under the set flow boundary conditions. Hence, simultaneous determination of thermal conductivity and flow velocity is expected to be feasible with this sensor under these circumstances, which, in turn, allows medium-independent flow sensing for a such selected set of gases. Experimental results show that the measurement resolution and maximum inaccuracy of lambda within the prescribed flow conditions are approximately equal to 2.445% and 3.18 + 4.20% (nonlinearity + velocity dependence) of the actual thermal conductivity, respectively. (C) 2014 Elsevier B.V. All rights reserved.
Huber T, Lambrecht A, Schmidt J, Karpa L, Schaetz T
A far-off-resonance optical trap for a Ba+ ion.
2014 Nat Commun, Band: 5, Seiten: 5587 - 5587
Moradi N, Greiner A, Melchionna S, Rao F, Succi S
A hydro-kinetic scheme for the dynamics of hydrogen bonds in water-like fluids.
2014 Phys Chem Chem Phys, Band: 16, Nummer: 29, Seiten: 15510 - 15518
Murphy RF
A new era in bioimage informatics.
2014 Bioinformatics, Band: 30, Nummer: 10, Seiten: 1353 - 1353
Feuerstein TJ
A pharmacological paradox: may a neutral antagonist shift an agonist concentration-response curve to the left?
2014 N-s Arch Pharmacol, Band: 387, Nummer: 7, Seiten: 601 - 603
Levi F, Mintert F
A quantitative theory of coherent delocalization
2014 New J Phys, Band: 16, Seite: 033007
Mueller K, Siegel D, ..., Decker E, Reski R, Weber W, Zurbriggen M
A red light-controlled synthetic gene expression switch for plant systems
2014 MOLECULAR BIOSYSTEMS, Band: 10, Nummer: 7, Seiten: 1679 - 1688
KurzfassungOn command control of gene expression in time and space is required for the comprehensive analysis of key plant cellular processes. Even though some chemical inducible systems showing satisfactory induction features have been developed, they are inherently limited in terms of spatiotemporal resolution and may be associated with toxic effects. We describe here the first synthetic light-inducible system for the targeted control of gene expression in plants. For this purpose, we applied an interdisciplinary synthetic biology approach comprising mammalian and plant cell systems to customize and optimize a split transcription factor based on the plant photoreceptor phytochrome B and one of its interacting factors (PIF6). Implementation of the system in transient assays in tobacco protoplasts resulted in strong (95-fold) induction in red light (660 nm) and could be instantaneously returned to the OFF state by subsequent illumination with far-red light (740 nm). Capitalizing on this toggle switch-like characteristic, we demonstrate that the system can be kept in the OFF state in the presence of 740 nm-supplemented white light, opening up perspectives for future application of the system in whole plants. Finally we demonstrate the system’s applicability in basic research, by the light-controlled tuning of auxin signalling networks in N. tabacum protoplasts, as well as its biotechnological potential for the chemical-inducer free production of therapeutic proteins in the moss P. patens.
Hosp J, Ribarits A, ..., Palme K, et al.
A tobacco homolog of DCN1 is involved in pollen development and embryogenesis (vol 33, pg 1187, 2014)
2014 PLANT CELL REPORTS, Band: 33, Nummer: 11, Seiten: 1933 - 1934
Xu J, Ding Z, ..., Werck-Reichhart D, Schreiber L, et.al.
ABORTED MICROSPORES Acts as a Master Regulator of Pollen Wall Formation in Arabidopsis.
2014 Plant Cell, Band: 26, Nummer: 4, Seiten: 1544 - 1556
Hacon C, McKernan J, Xu C
ACC for log canonical thresholds
2014 Annals of Mathematics, Band: 180, Nummer: 2, Seiten: 523 - 571
Dumit VI, Kuttner V, Kappler J, Piera-Velazquez S, Jimenez SA, Bruckner-Tuderman L, Uitto J, Dengjel J
Altered MCM protein levels and autophagic flux in aged and systemic sclerosis dermal fibroblasts.
2014 J Invest Dermatol, Band: 134, Nummer: 9, Seiten: 2321 - 2330
Kyle SD, Beattie L, Spiegelhalder K, Rogers Z, Espie CA
Altered emotion perception in insomnia disorder.
2014 Sleep, Band: 37, Nummer: 4, Seiten: 775 - 783
Kukenshoner T, Hagemann U, ..., Einsle O, Mueller K, Arndt K
Analysis of Selected and Designed Chimeric D- and L-alpha-Helix Assemblies
2014 BIOMACROMOLECULES, Band: 15, Nummer: 9, Seiten: 3296 - 3305
KurzfassungD-Peptides have been attributed pharmacological advantages over regular L-peptides, yet design rules are largely unknown. Based on a designed coiled coil-like D/L heterotetramer, named L-Base/D-Acid, we generated a library offering alternative residues for interaction with the D-peptide. Phage display selection yielded one predominant peptide, named HelixA, that differed at 13 positions from the scaffold helix. In addition to the observed D-/L-heterotetramers, ratio-dependent intermediate states were detected by isothermal titration calorimetry. Importantly, the formation of the selected HelixA/D-Acid bundle passes through fewer intermediate states than L-Base/D-Acid. Back mutation of HelixA core residues to L-Base (HelixLL) revealed that the residues at e/g-positions are responsible for the different intermediates. Furthermore, a Val-core variant (PeptideVV) was completely devoid of binding D-Acid, whereas an Ile-core helix (HelixII) interacted with D-Acid in a significantly more specific complex than L-Base.
Aubry-Hivet D, Nziengui H, Rapp K, Oliveira O, Paponov I, Li Y, Hauslage J, Vagt N, Braun M, Ditengou F, Dovzhenko A, Palme K
Analysis of gene expression during parabolic flights reveals distinct early gravity responses in Arabidopsis roots
2014 PLANT BIOLOGY, Band: 16, Nummer: 1, SI, Seiten: 129 - 141
KurzfassungPlant roots are among most intensively studied biological systems in gravity research. Altered gravity induces asymmetric cell growth leading to root bending. Differential distribution of the phytohormone auxin underlies root responses to gravity, being coordinated by auxin efflux transporters from the PIN family. The objective of this study was to compare early transcriptomic changes in roots of Arabidopsis thaliana wild type, and pin2 and pin3 mutants under parabolic flight conditions and to correlate these changes to auxin distribution. Parabolic flights allow comparison of transient 1-g, hypergravity and microgravity effects in living organisms in parallel. We found common and mutation-related genes differentially expressed in response to transient microgravity phases. Gene ontology analysis of common genes revealed lipid metabolism, response to stress factors and light categories as primarily involved in response to transient microgravity phases, suggesting that fundamental reorganisation of metabolic pathways functions upstream of a further signal mediating hormonal network. Gene expression changes in roots lacking the columella-located PIN3 were stronger than in those deprived of the epidermis and cortex cell-specific PIN2. Moreover, repetitive exposure to microgravity/hypergravity and gravity/hypergravity flight phases induced an up-regulation of auxin responsive genes in wild type and pin2 roots, but not in pin3 roots, suggesting a critical function of PIN3 in mediating auxin fluxes in response to transient microgravity phases. Our study provides important insights towards understanding signal transduction processes in transient microgravity conditions by combining for the first time the parabolic flight platform with the transcriptome analysis of different genetic mutants in the model plant, Arabidopsis.
Asplund M, Boehler C, Stieglitz T
Anti-inflammatory polymer electrodes for glial scar treatment: bringing the conceptual idea to future results.
2014 Front Neuroeng, Band: 7, Seiten: 9 - 9
Bode C, Diedrich B, ..., Knuefermann P, Baumgarten G
Antibiotics regulate the immune response in both presence and absence of lipopolysaccharide through modulation of Toll-like receptors, cytokine production and phagocytosis in vitro.
2014 Int Immunopharmacol, Band: 18, Nummer: 1, Seiten: 27 - 34
Becker A, Dengjel J
Autophagosomal Proteome Analysis by Protein Correlation Profiling-SILAC
2014 STABLE ISOTOPE LABELING BY AMINO ACIDS IN CELL CULTURE (SILAC): METHODS AND PROTOCOLS, Band: 1188, Seiten: 271 - 279
KurzfassungAutophagy is one of the two major degradation pathways within eukaryotic cells. Nevertheless, little is known about the protein composition of autophagosomes, the vesicles shuttling proteins to lysosomes for degradation. Protein correlation profiling in combination with stable isotope labeling by amino acids in cell culture is a stringent method to investigate the dynamics of the autophagosomal proteome. It enables the discrimination between autophagosomal and co-purifying proteins identifying organellar candidate proteins for further investigation.
Hege C, Proksch S, Siegel-Axel D, Schiller S
Biodegradable polymers for tissue engineering made with non-toxic catalysts
2014 JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Band: 8, Nummer: 1, SI, Seiten: 444 - 445
Zhang Y, Liu C, Balaeff A, Skourtis SS, Beratan DN
Biological charge transfer via flickering resonance.
2014 P Natl Acad Sci Usa, Band: 111, Nummer: 28, Seiten: 10049 - 10054
Harb J, Saleh O, ..., Reski R, Schwab W
Changes in Polyphenols and Expression Levels of Related Genes in ‘Duke’ Blueberries Stored under High CO2 Levels
2014 JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, Band: 62, Nummer: 30, Seiten: 7460 - 7467
KurzfassungBlueberries are highly perishable fruits, and consequently, storage under high CO2 and low O-2 levels is recommended to preserve the highly appreciated polyphenols. However, high CO2 levels might be detrimental for certain cultivars. The aim of this study was to investigate the impact of storage conditions on various quality parameters, including polyphenol composition in ‘Duke’ berries. Results show that storage under 18 kPa CO2, coupled with 3 kPa O-2 resulted in accelerated softening of berries, which was accompanied by lower levels compared to other conditions of hexosides and arabinosides of malvidin, petunidin, cyanidine, and delphinidin. However, this storage condition had no negative impact on chlorogenic acid levels. Expression data of key polyphenol-biosynthesis genes showed higher expression levels of all investigated genes at harvest time compared to all storage conditions. Of particular importance is the expression level of chalcone synthase (VcCHS), which is severely affected by storage at 18 kPa CO2.
Hagen S, Mattay D, Rauber C, Muller KM, Arndt KM
Characterization and inhibition of AF10-mediated interaction.
2014 J Pept Sci, Band: 20, Nummer: 6, Seiten: 385 - 397
Rigbolt KT, Zarei M, Sprenger A, Becker AC, Diedrich B, Huang X, Eiselein S, Kristensen AR, Gretzmeier C, Andersen JS, Zi Z, Dengjel J
Characterization of early autophagy signaling by quantitative phosphoproteomics.
2014 Autophagy, Band: 10, Nummer: 2, Seiten: 356 - 371
Fu C, Ao J, Dettmann A, Seiler S, Free SJ
Characterization of the Neurospora crassa cell fusion proteins, HAM-6, HAM-7, HAM-8, HAM-9, HAM-10, AMPH-1 and WHI-2.
2014 Plos One, Band: 9, Nummer: 10, Seiten: e107773 - e107773
Ra YS, Tichy M, ..., Mintert F, Buchleitner A, Kim YH
Comment on ‘Non-monotonic projection probabilities as a function of distinguishability’
2014 NEW JOURNAL OF PHYSICS, Band: 16
KurzfassungA recent work (Bjork and Shabbir 2014 New J. Phys. 16 013006) claims that nonmonotonic structures found in the many-particle quantum-to-classical transition (Ra et al 2013 Proc. Natl Acad. Sci. USA 110 1227-31; Tichy et al 2011 Phys. Rev. A 83 062111) are not exclusive to the many-body domain, but they also appear for single-photon as well as for semi-classical systems. We show that these situations, however, do not incorporate any quantum-to-classical transition, which makes the claims unsustainable.
Rzepiela A, Schaudinnus N, Buchenberg S, Hegger R, Stock G
Communication: Microsecond peptide dynamics from nanosecond trajectories: A Langevin approach
2014 JOURNAL OF CHEMICAL PHYSICS, Band: 141, Nummer: 24
KurzfassungBased on a given time series, the data-driven Langevin equation (dLE) estimates the drift and the diffusion field of the dynamics, which are then employed to reproduce the essential statistical and dynamical features of the original time series. Because the propagation of the dLE requires only local information, the input data are neither required to be Boltzmann weighted nor to be a continuous trajectory. Similar to a Markov state model, the dLE approach therefore holds the promise of predicting the long-time dynamics of a biomolecular system from relatively short trajectories which can be run in parallel. The practical applicability of the approach is shown to be mainly limited by the initial sampling of the system’s conformational space obtained from the short trajectories. Adopting extensive molecular dynamics simulations of the unfolding and refolding of a short peptide helix, it is shown that the dLE approach is able to describe microsecond conformational dynamics from a few hundred nanosecond trajectories. In particular, the dLE quantitatively reproduces the free energy landscape and the associated conformational dynamics along the chosen five-dimensional reaction coordinate. (c) 2014 AIP Publishing LLC.
Rudnicki L, Puchala Z, Horodecki P, Zyczkowski K
Constructive entanglement test from triangle inequality
2014 JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL, Band: 47, Nummer: 42, SI, Seite: 424035
KurzfassungWe derive a simple lower bound on the geometric measure of entanglement for mixed quantum states in the case of a general multipartite system. The main ingredient of the presented derivation is the triangle inequality applied to the root infidelity distance in the space of density matrices. The obtained bound leads to entanglement criteria with a straightforward interpretation. The proposed criteria provide an experimentally accessible, powerful entanglement test.
Li M
Current evidence of epidermal barrier dysfunction and thymic stromal lymphopoietin in the atopic march.
2014 Eur Respir Rev, Band: 23, Nummer: 133, Seiten: 292 - 298
Renault H, Bassard JE, Hamberger B, Werck-Reichhart D
Cytochrome P450-mediated metabolic engineering: current progress and future challenges.
2014 Curr Opin Plant Biol, Band: 19, Seiten: 27 - 34
Himmel D, Krossing I, Schnepf A
Dative bonds in main-group compounds: a case for fewer arrows!
2014 Angew Chem Int Edit, Band: 53, Nummer: 2, Seiten: 370 - 374
Labi V, Woess C, Tuzlak S, Erlacher M, Bouillet P, Strasser A, Tzankov A, Villunger A
Deregulated cell death and lymphocyte homeostasis cause premature lethality in mice lacking the BH3-only proteins Bim and Bmf.
2014 Blood, Band: 123, Nummer: 17, Seiten: 2652 - 2662
Morath V, Truong DJ, ..., Wiedemann G, Reski R, Skerra A
Design and Characterization of a Modular Membrane Protein Anchor to Functionalize the Moss Physcomitrella patens with Extracellular Catalytic and/or Binding Activities
2014 ACS SYNTHETIC BIOLOGY, Band: 3, Nummer: 12, Seiten: 990 - 994
KurzfassungHeterologous enzymes and binding proteins were secreted by the moss Physcomitrella patens or anchored extracellularly on its cell membrane in order to functionalize the apoplast as a biochemical reaction compartment. This modular membrane anchoring system utilizes the signal peptide and the transmembrane segment of the somatic embryogenesis receptor-like kinase (SERK), which were identified in a comprehensive bioinformatic analysis of the P. patens genome. By fusing the soluble enzyme NanoLuc luciferase to the signal peptide, its secretion capability was confirmed in vivo. The membrane localization of hybrid proteins comprising the SERK signal peptide, NanoLuc or other functional modules, the SERK transmembrane anchor, and a C-terminal GFP reporter was demonstrated using fluorescence microscopy as well as site-specific proteolytic release of the extracellular enzyme domain. Our membrane anchoring system enables the expression of various functional proteins in the apoplast of P. patens, empowering this photoautotrophic organism for biotechnological applications.
Jia F, Liu Z, Zaitsev M, Hennig J, Korvink J
Design multiple-layer gradient coils using least-squares finite element method
2014 STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION, Band: 49, Nummer: 3, Seiten: 523 - 535
KurzfassungThe design of gradient coils for magnetic resonance imaging is an optimization task in which a specified distribution of the magnetic field inside a region of interest is generated by choosing an optimal distribution of a current density geometrically restricted to specified non-intersecting design surfaces, thereby defining the preferred coil conductor shapes. Instead of boundary integral type methods, which are widely used to design coils, this paper proposes an optimization method for designing multiple layer gradient coils based on a finite element discretization. The topology of the gradient coil is expressed by a scalar stream function. The distribution of the magnetic field inside the computational domain is calculated using the least-squares finite element method. The first-order sensitivity of the objective function is calculated using an adjoint equation method. The numerical operations needed, in order to obtain an effective optimization procedure, are discussed in detail. In order to illustrate the benefit of the proposed optimization method, example gradient coils located on multiple surfaces are computed and characterised.
Al-Ahmad A, Zou P, Solarte DL, Hellwig E, Steinberg T, Lienkamp K
Development of a standardized and safe airborne antibacterial assay, and its evaluation on antibacterial biomimetic model surfaces.
2014 Plos One, Band: 9, Nummer: 10, Seiten: e111357 - e111357
Bruckner-Tuderman L, Has C
Disorders of the cutaneous basement membrane zone-the paradigm of epidermolysis bullosa.
2014 Matrix Biol, Band: 33, Seiten: 29 - 34
Tebartz van Elst L, Maier S, Fangmeier T, Endres D, Mueller G, Nickel K, Ebert D, Lange T, Hennig J, Biscaldi M, Riedel A, Perlov E
Disturbed cingulate glutamate metabolism in adults with high-functioning autism spectrum disorder: evidence in support of the excitatory/inhibitory imbalance hypothesis
2014 MOLECULAR PSYCHIATRY, Band: 19, Nummer: 12, Seiten: 1314 - 1325
KurzfassungOver the last few years, awareness of autism spectrum disorder (ASD) in adults has increased. The precise etiology of ASD is still unresolved. Animal research, genetic and postmortem studies suggest that the glutamate (Glu) system has an important role, possibly related to a cybernetic imbalance between neuronal excitation and inhibition. To clarify the possible disruption of Glu metabolism in adults with high-functioning autism, we performed a magnetic resonance spectroscopy (MRS) study investigating the anterior cingulate cortex (ACC) and the cerebellum in adults with high-functioning ASD. Twenty-nine adult patients with high-functioning ASD and 29 carefully matched healthy volunteers underwent MRS scanning of the pregenual ACC and the left cerebellar hemisphere. Metabolic data were compared between groups and were correlated with psychometric measures of autistic features. We found a significant decrease in the cingulate N-acetyl-aspartate (NAA) and the combined Glu and glutamine (Glx) signals in adults with ASD, whereas we did not find other metabolic abnormalities in the ACC or the cerebellum. The Glx signal correlated significantly with psychometric measures of autism, particularly with communication deficits. Our data support the hypothesis that there is a link between disturbances of the cingulate NAA and Glx metabolism, and autism. The findings are discussed in the context of the hypothesis of excitatory/inhibitory imbalance in autism. Further research should clarify the specificity and dynamics of these findings regarding other neuropsychiatric disorders and other brain areas.
Tebartz van Elst L, Maier S, Fangmeier T, Endres D, Mueller GT, Nickel K, Ebert D, Lange T, Hennig J, Biscaldi M, Riedel A, Perlov E
Disturbed cingulate glutamate metabolism in adults with high-functioning autism spectrum disorder: evidence in support of the excitatory/inhibitory imbalance hypothesis.
2014 Mol Psychiatr, Band: 19, Nummer: 12, Seiten: 1314 - 1325
Hofer R, Boachon B, Renault H, Gavira C, Miesch L, Iglesias J, Ginglinger JF, Allouche L, Miesch M, Grec S, Larbat R, Werck-Reichhart D
Dual function of the cytochrome P450 CYP76 family from Arabidopsis thaliana in the metabolism of monoterpenols and phenylurea herbicides.
2014 Plant Physiol, Band: 166, Nummer: 3, Seiten: 1149 - 1161
Reyes-Romero D, Behrmann O, Dame G, Urban G
Dynamic thermal sensor for biofilm monitoring
2014 SENSORS AND ACTUATORS A-PHYSICAL, Band: 213, Seiten: 43 - 51
KurzfassungA novel sensor principle to continuously monitor biofilm formation by Enterococcus faecalis is presented. The sensor consists of a small heater and a temperature probe (thermistor); both are located on a thermally insulating, silicon nitride membrane. Biofilm is allowed to develop in M17-medium at 37 degrees C on the surface of the membrane. Electrical current applied to the heater produces a steady sinusoidal power signal at 40 Hz. The resulting temperature oscillations are captured by the temperature probe. Their amplitude and phase shift are influenced by the thickness and composition of the biofilm. Results show that the sensor system is able to monitor the evolution of biofilms for large time frames (hours). It also features very stable baseline measurements that outperform other types of sensor systems. A proof-of-concept by means of an antibiotics-growth-inhibition test is achieved. (C) 2014 Elsevier B.V. All rights reserved.
Ji K, Maier S, Komnik A
Dynamical response of ultracold interacting fermion-boson mixtures
2014 Physica B, Band: 454, Seiten: 224 - 234
Kangas J, Naik A, Murphy R
Efficient discovery of responses of proteins to compounds using active learning
2014 BMC BIOINFORMATICS, Band: 15
KurzfassungBackground: Drug discovery and development has been aided by high throughput screening methods that detect compound effects on a single target. However, when using focused initial screening, undesirable secondary effects are often detected late in the development process after significant investment has been made. An alternative approach would be to screen against undesired effects early in the process, but the number of possible secondary targets makes this prohibitively expensive. Results: This paper describes methods for making this global approach practical by constructing predictive models for many target responses to many compounds and using them to guide experimentation. We demonstrate for the first time that by jointly modeling targets and compounds using descriptive features and using active machine learning methods, accurate models can be built by doing only a small fraction of possible experiments. The methods were evaluated by computational experiments using a dataset of 177 assays and 20,000 compounds constructed from the PubChem database. Conclusions: An average of nearly 60% of all hits in the dataset were found after exploring only 3% of the experimental space which suggests that active learning can be used to enable more complete characterization of compound effects than otherwise affordable. The methods described are also likely to find widespread application outside drug discovery, such as for characterizing the effects of a large number of compounds or inhibitory RNAs on a large number of cell or tissue phenotypes.
Botiz I, Freyberg P, Leordean C, Gabudean AM, Astilean S, Yang AC, Stingelin N
Enhancing the photoluminescence emission of conjugated MEH-PPV by light processing.
2014 Acs Appl Mater Inter, Band: 6, Nummer: 7, Seiten: 4974 - 4979
Ramantani G, Kadish NE, ..., Feuerstein TJ, et.al.
Epilepsy Surgery for Glioneuronal Tumors in Childhood: Avoid Loss of Time.
2014 Neurosurgery, Band: 74, Nummer: 6, Seiten: 648 - 657
Mueller SJ, Reski R
Evolution and communication of subcellular compartments: An integrated approach.
2014 Plant Signal Behav, Band: 9
Kiritsi D, Nanda A, Kohlhase J, Bernhard Ca, Bruckner-Tuderman L, Happle R, Has C
Extensive Postzygotic Mosaicism for a Novel Keratin 10 Mutation in Epidermolytic Ichthyosis
2014 ACTA DERMATO-VENEREOLOGICA, Band: 94, Nummer: 3, Seiten: 346 - 348
Chandrasekaran S, Sato N, Toelle F, Muelhaupt R, Fiedler B, Schulte K
Fracture toughness and failure mechanism of graphene based epoxy composites
2014 COMPOSITES SCIENCE AND TECHNOLOGY, Band: 97, Seiten: 90 - 99
KurzfassungThe present study investigates the effect of addition of three different types on carbon nano-fillers on fracture toughness (K-IC) and failure mechanism of epoxy based polymer nano-composites. The carbon nano-fillers were dispersed in the epoxy matrix using a three-roll mill and the three nano-fillers used for this experiment were (i) thermally reduced graphene oxide (TRGO); (ii) graphite nano-platelets (GNP); and (iii) multi-wall carbon nano-tubes (MWCNT). The fracture toughness was measured as a function of weight percentage of the filler using single edge notch three-point-bending tests. The toughening effect of TRGO was most significant resulting in 40% increase in K-IC for 0.5 wt% of filler. On the other hand, the enhancements in toughness were 25% for GNP/epoxy and 8% for MWCNT/epoxy. Investigations on fracture surface revealed that crack pinning or bi-furcation by TRGO and crack face separation initiated from TRGO contributed to enhance the fracture toughness. Based on the observations, a schematic explaining the crack propagation in graphene/epoxy composite and the interaction of crack front with graphene particles was proposed. (C) 2014 Elsevier Ltd. All rights reserved.
Scarel F, Mateo-Alonso A
Fullerene C-60 Architectures in Materials Science
2014 CARBON NANOMATERIALS, 2ND EDITION, Seiten: 47 - 87
Dettmann A, Heilig Y, Valerius O, Ludwig S, Seiler S
Fungal communication requires the MAK-2 pathway elements STE-20 and RAS-2, the NRC-1 adapter STE-50 and the MAP kinase scaffold HAM-5.
2014 Plos Genet, Band: 10, Nummer: 11
Decker EL, Parsons J, Reski R
Glyco-engineering for biopharmaceutical production in moss bioreactors.
2014 Front Plant Sci, Band: 5, Seiten: 346 - 346
Berger R, Fuchter M, Krossing I, Rzepa H, Schaefer J, Scherer Ha
Gold(I) mediated rearrangement of [7]-helicene to give a benzo[cd]pyrenium cation embedded in a chiral framework
2014 CHEMICAL COMMUNICATIONS, Band: 50, Nummer: 40, Seiten: 5251 - 5253
KurzfassungThe facile gold-mediated skeletal rearrangement of [7]-helicene into a cationic polyaromatic hydrocarbon is described. We report in-depth studies on the structure and aromaticity of this novel stable cation and propose a mechanism for its formation.
Choudhary S, Gozalvez C, Higelin A, Krossing I, Melle-Franco M, Mateo-Alonso A
Hexaazatrinaphthylenes with different twists.
2014 Chem-eur J, Band: 20, Nummer: 6, Seiten: 1525 - 1528
Jain A, Stock G
Hierarchical folding free energy landscape of HP35 revealed by most probable path clustering.
2014 J Phys Chem B, Band: 118, Nummer: 28, Seiten: 7750 - 7760
Valido AA, Levi F, Mintert F
Hierarchies of multipartite entanglement for continuous variable states
2014 Phys Rev A, Band: 90, Seite: 052321
Beike A, Jaeger C, Zink F, Decker E, Reski R
High contents of very long-chain polyunsaturated fatty acids in different moss species
2014 PLANT CELL REPORTS, Band: 33, Nummer: 2, Seiten: 245 - 254
KurzfassungMosses have high contents of polyunsaturated fatty acids. Tissue-specific differences in fatty acid contents and fatty acid desaturase (FADS)-encoding gene expression exist. The arachidonic acid-synthesizing FADS operate in the ER. Polyunsaturated fatty acids (PUFAs) are important cellular compounds with manifold biological functions. Many PUFAs are essential for the human diet and beneficial for human health. In this study, we report on the high amounts of very long-chain (vl) PUFAs (a parts per thousand yenC(20)) such as arachidonic acid (AA) in seven moss species. These species were established in axenic in vitro culture, as a prerequisite for comparative metabolic studies under highly standardized laboratory conditions. In the model organism Physcomitrella patens, tissue-specific differences in the fatty acid compositions between the filamentous protonema and the leafy gametophores were observed. These metabolic differences correspond with differential gene expression of fatty acid desaturase (FADS)-encoding genes in both developmental stages, as determined via microarray analyses. Depending on the developmental stage and the species, AA amounts for 6-31 %, respectively, of the total fatty acids. Subcellular localization of the corresponding FADS revealed the endoplasmic reticulum as the cellular compartment for AA synthesis. Our results show that vlPUFAs are highly abundant metabolites in mosses. Standardized cultivation techniques using photobioreactors along with the availability of the P. patens genome sequence and the high rate of homologous recombination are the basis for targeted metabolic engineering in moss. The potential of producing vlPUFAs of interest from mosses will be highlighted as a promising area in plant biotechnology.
Xie Y, Heida T, Stegenga J, Zhao Y, Moser A, Tronnier V, Feuerstein TJ, Hofmann UG
High-frequency electrical stimulation suppresses cholinergic accumbens interneurons in acute rat brain slices through GABA receptors.
2014 Eur J Neurosci
Carnevalli LS, R. Scognamiglio R., ...., Erlacher M, et.al.
Improved HSC reconstitution and protection from inflammatory stress and chemotherapy in mice lacking granzyme B.
2014 J Exp Med, Band: 211, Nummer: 5, Seiten: 769 - 779
Kukenshoner T, Wohlwend D, ..., Einsle O, Muller KM, Arndt KM
Improving coiled coil stability while maintaining specificity by a bacterial hitchhiker selection system.
2014 J Struct Biol, Band: 186, Nummer: 3, Seiten: 335 - 348
Zimmermann J, Mulet R, Scholes GD, Wellens T, Buchleitner A
Improving triplet-triplet-annihilation based upconversion systems by tuning their topological structure.
2014 J Chem Phys, Band: 141, Nummer: 18, Seiten: 184104 - 184104
Kalfalah F, Sobek S, Bornholz B, Gotz-Rosch C, Tigges J, Fritsche E, Krutmann J, Kohrer K, Deenen R, Ohse S, Boerries M, Busch H, Boege F
Inadequate mito-biogenesis in primary dermal fibroblasts from old humans is associated with impairment of PGC1A-independent stimulation.
2014 Exp Gerontol, Band: 56, Seiten: 59 - 68
Lorenz R, Bock J, Snyder J, Korvink J, Jung B, Markl M
Influence of Eddy Current, Maxwell and Gradient Field Corrections on 3D Flow Visualization of 3D CINE PC-MRI Data
2014 MAGNETIC RESONANCE IN MEDICINE, Band: 72, Nummer: 1, Seiten: 33 - 40
KurzfassungPurpose: The measurement of velocities based on phase contrast MRI can be subject to different phase offset errors which can affect the accuracy of velocity data. The purpose of this study was to determine the impact of these inaccuracies and to evaluate different correction strategies on three-dimensional visualization. Methods: Phase contrast MRI was performed on a 3 T system (Siemens Trio) for in vitro (curved/straight tube models; venc: 0.3 m/s) and in vivo (aorta/intracranial vasculature; venc: 1.5/0.4 m/s) data. For comparison of the impact of different magnetic field gradient designs, in vitro data was additionally acquired on a wide bore 1.5 T system (Siemens Espree). Different correction methods were applied to correct for eddy currents, Maxwell terms, and gradient field inhomogeneities. Results: The application of phase offset correction methods lead to an improvement of three-dimensional particle trace visualization and count. The most pronounced differences were found for in vivo/in vitro data (68%/82% more particle traces) acquired with a low venc (0.3 m/s/0.4 m/s, respectively). In vivo data acquired with high venc (1.5 m/s) showed noticeable but only minor improvement. Conclusion: This study suggests that the correction of phase offset errors can be important for a more reliable visualization of particle traces but is strongly dependent on the velocity sensitivity, object geometry, and gradient coil design. (C) 2013 Wiley Periodicals, Inc.
Baglioni C, Spiegelhalder K, Regen W, Feige B, Nissen C, Lombardo C, Violani C, Hennig J, Riemann D
Insomnia disorder is associated with increased amygdala reactivity to insomnia-related stimuli.
2014 Sleep, Band: 37, Nummer: 12, Seiten: 1907 - 1917
Huber MC, Schreiber A, Wild W, Benz K, Schiller SM
Introducing a combinatorial DNA-toolbox platform constituting defined protein-based biohybrid-materials.
2014 Biomaterials, Band: 35, Nummer: 31, Seiten: 8767 - 8779
Scheidt CE, Waller E, Endorf K, Schmidt S, Koenig R, Zeeck A, Joos Andreas, Lacour Michael
Is brief psychodynamic psychotherapy in primary fibromyalgia syndrome with concurrent depression an effective treatment? A randomized controlled trial (vol 35, pg 160, 2013)
2014 GENERAL HOSPITAL PSYCHIATRY, Band: 36, Nummer: 1
Lindner AC, Lang D, Seifert M, Podlesakova K, Novak O, Strnad M, Reski R, von Schwartzenberg K
Isopentenyltransferase-1 (IPT1) knockout in Physcomitrella together with phylogenetic analyses of IPTs provide insights into evolution of plant cytokinin biosynthesis.
2014 J Exp Bot, Band: 65, Nummer: 9, Seiten: 2533 - 2543
Hiss M, Laule O, ..., Reski R, ..., Rensing S
Large-scale gene expression profiling data for the model moss Physcomitrella patens aid understanding of developmental progression, culture and stress conditions
2014 PLANT JOURNAL, Band: 79, Nummer: 3, Seiten: 530 - 539
KurzfassungThe moss Physcomitrella patens is an important model organism for studying plant evolution, development, physiology and biotechnology. Here we have generated microarray gene expression data covering the principal developmental stages, culture forms and some environmental/stress conditions. Example analyses of developmental stages and growth conditions as well as abiotic stress treatments demonstrate that (i) growth stage is dominant over culture conditions, (ii) liquid culture is not stressful for the plant, (iii) low pH might aid protoplastation by reduced expression of cell wall structure genes, (iv) largely the same gene pool mediates response to dehydration and rehydration, and (v) AP2/EREBP transcription factors play important roles in stress response reactions. With regard to the AP2 gene family, phylogenetic analysis and comparison with Arabidopsis thaliana shows commonalities as well as uniquely expressed family members under drought, light perturbations and protoplastation. Gene expression profiles for P. patens are available for the scientific community via the easy-to-use tool at https://www.genevestigator.com. By providing large-scale expression profiles, the usability of this model organism is further enhanced, for example by enabling selection of control genes for quantitative real-time PCR. Now, gene expression levels across a broad range of conditions can be accessed online for P. patens.
Rahimi K, Botiz Io, Agumba J, Motamen S, Stingelin N, Reiter G
Light absorption of poly(3-hexylthiophene) single crystals
2014 RSC ADVANCES, Band: 4, Nummer: 22, Seiten: 11121 - 11123
KurzfassungWe report the local UV-Vis absorption behaviour of single crystals of conjugated poly-3-hexylthiophene (P3HT), obtained by crystallization in dilute solutions at elevated temperatures based on a self-seeding approach and characterized by high internal structural order.
Shang MM, Talukdar HA, Hofmann JJ, Niaudet C, Asl HF, Jain RK, Rossignoli A, Cedergren C, Silveira A, Gigante B, Leander K, de Faire U, Hamsten A, Ruusalepp A, Melander O, Ivert T, Michoel T, Schadt EE, Betsholtz C, Skogsberg J, Bjorkegren JL
Lim domain binding 2: a key driver of transendothelial migration of leukocytes and atherosclerosis.
2014 Arterioscl Throm Vas, Band: 34, Nummer: 9, Seiten: 2068 - 2077
Franchini F, Cui J, ..., Vedral V
Local Convertibility and the Quantum Simulation of Edge States in Many-Body Systems
2014 PHYSICAL REVIEW X, Band: 4, Nummer: 4
KurzfassungIn some many-body systems, certain ground-state entanglement (Renyi) entropies increase even as the correlation length decreases. This entanglement nonmonotonicity is a potential indicator of nonclassicality. In this work, we demonstrate that such a phenomenon, known as lack of local convertibility, is due to the edge-state (de) construction occurring in the system. To this end, we employ the example of the Ising chain, displaying an order-disorder quantum phase transition. Employing both analytical and numerical methods, we compute entanglement entropies for various system bipartitions (A\textbackslashB) and consider ground states with and without Majorana edge states. We find that the thermal ground states, enjoying the Hamiltonian symmetries, show lack of local convertibility if either A or B is smaller than, or of the order of, the correlation length. In contrast, the ordered (symmetry-breaking) ground state is always locally convertible. The edge-state behavior explains all these results and could disclose a paradigm to understand local convertibility in other quantum phases of matter. The connection we establish between convertibility and nonlocal, quantum correlations provides a clear criterion of which features a universal quantum simulator should possess to outperform a classical machine.
Bryan SJ, N.J. Burroughs, D. Shevela, J. Yu, E. Rupprecht, L.N. Liu, G. Mastroianni, Q. Xue, I. Llorente-Garcia, M.C. Leake, L.A. Eichacker, D. Schneider, P.J. Nixon, C.W. Mullineaux
Localisation and interactions of the Vipp1 protein in cyanobacteria.
2014 Mol Microbiol, Band: 94, Nummer: 5, Seiten: 1179 - 1195
Buchenberg S, Knecht V, Walser R, Hamm P, Stock G
Long-Range Conformational Transition of a Photoswitchable Allosteric Protein: Molecular Dynamics Simulation Study
2014 JOURNAL OF PHYSICAL CHEMISTRY B, Band: 118, Nummer: 47, SI, Seiten: 13468 - 13476
KurzfassungA local perturbation of a protein may lead to functional changes at some distal site. An example is the PDZ2 domain of human tyrosine phosphatase 1E, which shows an allosteric transition upon binding to a peptide ligand. Recently Buchli et al. presented a time-resolved study of this transition by covalently linking an azobenzene photoswitch across the binding groove and using a femtosecond laser pulse that triggers the cistrans photoisomerization of azobenzene. To aid the interpretation of these experiments, in this work seven microsecond runs of all-atom molecular dynamics simulations each for the wild-type PDZ2 in the ligand-bound and -free state, as well as the photoswitchable protein (PDZ2S) in the cis and trans states of the photoswitch, in explicit water were conducted. First the theoretical model is validated by recalculating the available NMR data from the simulations. By comparing the results for PDZ2 and PDZ2S, it is analyzed to what extent the photoswitch indeed mimics the free-bound transition. A detailed description of the conformational rearrangement following the cistrans photoisomerization of PDZ2S reveals a series of photoinduced structural changes that propagate from the anchor residues of the photoswitch via intermediate secondary structure segments to the C-terminus of PDZ2S. The changes of the conformational distribution of the C-terminal region is considered as the distal response of the isolated allosteric protein.
Livshits GI, Stern A, ..., Skourtis SS, et al.
Long-range charge transport in single G-quadruplex DNA molecules.
2014 Nat Nanotechnol, Band: 9, Nummer: 12, Seiten: 1040 - 1046
Kuttner V, Mack C, Gretzmeier C, Bruckner-Tuderman L, Dengjel J
Loss of collagen VII is associated with reduced transglutaminase 2 abundance and activity.
2014 J Invest Dermatol, Band: 134, Nummer: 9, Seiten: 2381 - 2389
More S, Bhosale R, Mateo-Alonso A
Low-LUMO pyrene-fused azaacenes.
2014 Chem-eur J, Band: 20, Nummer: 34, Seiten: 10626 - 10631
Nowag H, Guhl B, Thriene K, Romao S, Ziegler U, Dengjel J, Munz C
Macroautophagy Proteins Assist Epstein Barr Virus Production and Get Incorporated Into the Virus Particles.
2014 EBioMedicine, Band: 1, Nummer: 2-3, Seiten: 116 - 125
Tebartz van Elst L, Maier S, Fangmeier T, Endres D, Mueller GT, Nickel K, Ebert D, Lange T, Hennig J, Biscaldi M, Riedel A, Perlov E
Magnetic resonance spectroscopy comparing adults with high functioning autism and above average IQ.
2014 Mol Psychiatr, Band: 19, Nummer: 12, Seiten: 1251 - 1251
Rastogi V, Stanssens D, Samyn P
Mechanism for Tuning the Hydrophobicity of Microfibrillated Cellulose Films by Controlled Thermal Release of Encapsulated Wax
2014 MATERIALS, Band: 7, Nummer: 11, Seiten: 7196 - 7216
KurzfassungAlthough films of microfibrillated cellulose (MFC) have good oxygen barrier properties due to its fine network structure, properties strongly deteriorate after absorption of water. In this work, a new approach has been followed for actively tuning the water resistance of a MFC fiber network by the inclusion of dispersed organic nanoparticles with encapsulated plant wax. The modified pulp suspensions have been casted into films and were subsequently cured at 40 to 220 degrees C. As such, static water contact angles can be specifically tuned from 120 to 150 degrees by selection of the curing temperature in relation with the intrinsic transition temperatures of the modified pulp, as determined by thermal analysis. The appearance of encapsulated wax after curing was followed by a combination of morphological analysis, infrared spectroscopy and Raman mapping, showing balanced mechanisms of progressive release and migration of wax into the fiber network controlling the surface properties and water contact angles. Finally, the appearance of nanoparticles covered with a thin wax layer after complete thermal release provides highest hydrophobicity.
Kiritsi D, Garcia M, ..., Bruckner-Tuderman L, Pasmooij AM
Mechanisms of natural gene therapy in dystrophic epidermolysis bullosa.
2014 J Invest Dermatol, Band: 134, Nummer: 8, Seiten: 2097 - 2104
Spengler N, Moazenzadeh A, Meier R, Badilita V, Korvink J, Wallrabe U
Micro-fabricated Helmholtz coil featuring disposable microfluidic sample inserts for applications in nuclear magnetic resonance
2014 JOURNAL OF MICROMECHANICS AND MICROENGINEERING, Band: 24, Nummer: 3
KurzfassungIn this study, we report on a novel, multi-use, high-resolution NMR/MRI micro-detection probe for the screening of flat samples. It is based on a Helmholtz coil pair in the centre of the probe, built out of two 1.5 mm diameter wirebonded copper coils, resulting in a homogeneous distribution of the magnetic field. For liquids and suspensions, custom fabricated, disposable sample inserts are placed inside the pair and aligned automatically, preventing the sensor and the samples from contamination. The sensor was successfully tested in a 500 MHz (11.7 T) spectrometer where we achieved a linewidth of 1.79 Hz (3.58 ppb) of a water phantom. Nutation experiments revealed an overall B-1-field uniformity of 92% (ratio in signal intensity at flip angles of 810 degrees/90 degrees), leading to a homogeneous excitation of concentration limited samples. To demonstrate the imaging capabilities of the detector, we acquired images of a solid and a liquid sample-of a piece of leaf, directly inserted into the probe and of a sample insert, filled with a suspension of 50 mu m diameter polymer beads and deionized water, with in-plane resolutions of 20 x 20 mu m(2) and 10 x 10 mu m(2), respectively.
Meier R, Hoefflin J, Badilita V, Wallrabe U, Korvink J
Microfluidic integration of wirebonded microcoils for on-chip applications in nuclear magnetic resonance
2014 JOURNAL OF MICROMECHANICS AND MICROENGINEERING, Band: 24, Nummer: 4, Seite: 045021
KurzfassungWe present an integrated microfluidic device for on-chip nuclear magnetic resonance (NMR) studies of microscopic samples. The devices are fabricated by means of a MEMS compatible process, which joins the automatic wirebond winding of solenoidal microcoils and the manufacturing of a complex microfluidic network using dry-photoresist lamination. The wafer-scale cleanroom process is potentially capable of mass fabrication. Since the non-invasive NMR analysis technique is rather insensitive, particularly when microscopic sample volumes are to be investigated, we also focus on the optimization of the wirebonded microcoil for this purpose. The on-chip measurement of NMR signals from a 20 nl sample are evaluated for imaging analysis of microparticles, as well as for spectroscopy. Whereas the latter revealed that the sensitivity of the MEMS microcoil is comparable with hand-wound devices and achieves a full-width-half-maximum linewidth of 8 Hz, the imaging experiment demonstrated 10 mu m isotropic spatial resolution within an experiment time of 38 min for a 3D image with a field of view of 1 mm x 1 mm x 0.5 mm (500 000 voxels).
Bakhtina N, Korvink J
Microfluidic laboratories for C. elegans enhance fundamental studies in biology
2014 RSC ADVANCES, Band: 4, Nummer: 9, Seiten: 4691 - 4709
KurzfassungThe in vivo analysis of a small multicellular organism such as the nematode Caenorhabditis elegans, enables fundamental biomedical and environmental studies of a complete organism under normal physiological conditions. Continuous advancements in photonics, electronics, as well as the material sciences, are paving the way towards miniaturized bioanalytical systems, known as labs-on-a-chip (LOC). These microfluidic technologies facilitate the manipulation and study of nematodes in a precise, real-time, portable, and cost-effective manner, potentially for high throughput operation. In this paper we review all currently available “worm-on-a-chip” miniaturized systems that address the manipulation, detection, and study of the sensory response of C. elegans, and take a close look at their advantages, application challenges, and scientific potential. The paper aims to consolidate recent results of dedicated worm microsystems that target a better understanding of C. elegans.
Pigors M, Schwieger-Briel A, Leppert J, Kiritsi D, Kohlhase J, Bruckner-Tuderman L, Has C
Molecular heterogeneity of epidermolysis bullosa simplex: contribution of EXPH5 mutations.
2014 J Invest Dermatol, Band: 134, Nummer: 3, Seiten: 842 - 845
Dengjel J, Abeliovich H
Musical chairs during mitophagy.
2014 Autophagy, Band: 10, Nummer: 4, Seiten: 706 - 707
Varatharajan R, Joseph K, Loeffler S, Fuellgraf H, Hofmann UG, Moser A
N-Methyl-D-Aspartate Receptor Activation Interacts with Electrical High Frequency Stimulation in the Rat Caudate Nucleus in vitro and in vivo
2014 J Neurosci, Band: 4, Nummer: 1, Seiten: 1 - 8
Shklyarov D
NON-COMMUTATIVE HODGE STRUCTURES: TOWARDS MATCHING CATEGORICAL AND GEOMETRIC EXAMPLES
2014 T Am Math Soc, Band: 366, Nummer: 6, Seiten: 2923 - 2974
Kiritsi D, Garcia M, ..., Bruckner-Tuderman L, Pasmooij M, Has C
Natural gene therapy in dystrophic epidermolysis bullosa
2014 EXPERIMENTAL DERMATOLOGY, Band: 23, Nummer: 3
Shevchuk R, Agmon N, Rao F
Network analysis of proton transfer in liquid water.
2014 J Chem Phys, Band: 140, Nummer: 24, Seiten: 244502 - 244502
Svetovoy V, Sanders R, Ma K, Elwenspoek M
New type of microengine using internal combustion of hydrogen and oxygen
2014 SCIENTIFIC REPORTS, Band: 4
KurzfassungMicrosystems become part of everyday life but their application is restricted by lack of strong and fast motors (actuators) converting energy into motion. For example, widespread internal combustion engines cannot be scaled down because combustion reactions are quenched in a small space. Here we present an actuator with the dimensions 100 x 100 x 5 mu m(3) that is using internal combustion of hydrogen and oxygen as part of its working cycle. Water electrolysis driven by short voltage pulses creates an extra pressure of 0.5-4 bar for a time of 100-400 mu s in a chamber closed by a flexible membrane. When the pulses are switched off this pressure is released even faster allowing production of mechanical work in short cycles. We provide arguments that this unexpectedly fast pressure decrease is due to spontaneous combustion of the gases in the chamber. This actuator is the first step to truly microscopic combustion engines.
Hege C, Schiller S
Non-toxic catalysts for ring-opening polymerizations of biodegradable polymers at room temperature for biohybrid materials
2014 GREEN CHEMISTRY, Band: 16, Nummer: 3, Seiten: 1410 - 1416
KurzfassungBiodegradable biopolymers are versatile materials with a wide range of applications including suture, scaffolds, growth chambers and matrix materials for tissue-engineering and regenerative medicine. Their synthesis is usually based on tin-salts at high temperatures. Strategies to replace tin are interesting due to the toxicity of tin for aquatic organisms and potentially problematic effects in higher organisms. In the framework of this study we investigate nontoxic iron catalysts (iron chloride, bromide and perchlorate) and their potential to facilitate ring-opening polymerizations (ROP) at room temperature. To find the best combination of a catalyst and an initiator for the ROP of e-caprolactone, three iron-catalysts were analysed with four different initiators (water, isopropyl alcohol, benzyl alcohol and 2-allyl phenol). Functional entities such as the allyl group are interesting for bioconjugation and may allow functional access to functional biohybrid materials. The polymerizations were carried out solvent free in bulk and yielded polymers in the range 10-20 kDa for large monomer to catalyst/initiator ratios analysed by GPC, NMR and MALDI-TOF. We find that commercial iron salts can replace tin salts in many cases and allow for the ROP of e-caprolactone at room temperature while tin(II) 2-ethylhexanoate Sn(Oct)2 does not facilitate ROP at room temperature. The use of iron based ROP catalysts opens interesting access to biopolymers utilizing a nontoxic metal ion at low temperatures in a solvent free reaction scheme saving energy and the environment.
Eisenberg T, Schroeder S, ..., Dengjel J, Sigrist SJ, Kroemer G, Madeo F
Nucleocytosolic depletion of the energy metabolite acetyl-coenzyme a stimulates autophagy and prolongs lifespan.
2014 Cell Metab, Band: 19, Nummer: 3, Seiten: 431 - 444
Alexandrov A, Mironov A, Morozov A, Natanzon S
On KP-integrable Hurwitz functions
2014 J High Energy Phys, Nummer: 11
Verdeny A, Rudnicki Ł, Müller CA, Mintert F
Optimal Control of Effective Hamiltonians
2014 Phys Rev Lett, Band: 113, Seite: 010501
Jacobsen S, Mintert F
Optimal correction of independent and correlated errors
2014 JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL, Band: 47, Nummer: 4
KurzfassungWe identify optimal quantum error correction codes for situations that do not admit perfect correction. We provide analytic n-qubit results for standard cases with correlated errors on multiple qubits and demonstrate significant improvements to the fidelity bounds and optimal entanglement decay profiles.
Sommerlade L, Mader M, Mader W, Timmer J, Thiel M, Grebogi C, Schelter B
Optimized spectral estimation for nonlinear synchronizing systems.
2014 Phys Rev E, Band: 89, Nummer: 3, Seiten: 032912 - 032912
Schelter B, Mader M, ..., Grebogi C, Thiel M
Overarching framework for data-based modelling
2014 EPL, Band: 105, Nummer: 3
KurzfassungOne of the main modelling paradigms for complex physical systems are networks. When estimating the network structure from measured signals, typically several assumptions such as stationarity are made in the estimation process. Violating these assumptions renders standard analysis techniques fruitless. We here propose a framework to estimate the network structure from measurements of arbitrary non-linear, non-stationary, stochastic processes. To this end, we propose a rigorous mathematical theory that underlies this framework. Based on this theory, we present a highly efficient algorithm and the corresponding statistics that are immediately sensibly applicable to measured signals. We demonstrate its performance in a simulation study. In experiments of transitions between vigilance stages in rodents, we infer small network structures with complex, time-dependent interactions; this suggests biomarkers for such transitions, the key to understand and diagnose numerous diseases such as dementia. We argue that the suggested framework combines features that other approaches followed so far lack. editor’s choice Copyright (c) EPLA, 2014
Cabello J, Samann J, Gomez-Orte E, Erazo T, Coppa A, Pujol A, Bussing I, Schulze B, Lizcano JM, Ferrer I, Baumeister R, Dalfo E
PDR-1/hParkin negatively regulates the phagocytosis of apoptotic cell corpses in Caenorhabditis elegans.
2014 Cell Death Dis, Band: 5, Seiten: e1120 - e1120
Fuchs S, Rensing-Ehl A, Erlacher M, et al.
Patients with T NK IL-2 receptor gamma chain deficiency have differentially impaired cytokine signaling resulting in severe combined immunodeficiency.
2014 Eur J Immunol, Band: 44, Nummer: 10, Seiten: 3129 - 3140
Chylek LA, Akimov V, Dengjel J, Rigbolt KT, Hu B, Hlavacek WS, Blagoev B
Phosphorylation site dynamics of early T-cell receptor signaling.
2014 Plos One, Band: 9, Nummer: 8, Seiten: e104240 - e104240
Bjorkegren JL, Hagg S, Talukdar HA, Foroughi Asl H, Jain RK, Cedergren C, Shang MM, Rossignoli A, Takolander R, Melander O, Hamsten A, Michoel T, Skogsberg J
Plasma cholesterol-induced lesion networks activated before regression of early, mature, and advanced atherosclerosis.
2014 Plos Genet, Band: 10, Nummer: 2, Seiten: e1004201 - e1004201
Bennett TA, ..., Decker EL, Reski R, Harrison CJ
Plasma membrane-targeted PIN proteins drive shoot development in a moss.
2014 Curr Biol, Band: 24, Nummer: 23, Seiten: 2776 - 2785
Sittel F, Jain A, Stock G
Principal component analysis of molecular dynamics: on the use of Cartesian vs. internal coordinates.
2014 J Chem Phys, Band: 141, Nummer: 1, Seiten: 014111 - 014111
Heilig Y, Dettmann A, Mourino-Perez RR, Schmitt K, Valerius O, Seiler S
Proper actin ring formation and septum constriction requires coordinated regulation of SIN and MOR pathways through the germinal centre kinase MST-1.
2014 Plos Genet, Band: 10, Nummer: 4, Seiten: e1004306 - e1004306
Dumit V, Kuttner V, Piera-Velazquez S, Jimenez S, Bruckner-Tuderman L, Uitto J, Dengjel J
Proteomics profiling suggests molecular similarities between aging and systemic sclerosis dermal fibroblasts
2014 JOURNAL OF INVESTIGATIVE DERMATOLOGY, Band: 134, Nummer: 8
Mueller S, Lang D, ..., Schlosser A, Reski R
Quantitative Analysis of the Mitochondrial and Plastid Proteomes of the Moss Physcomitrella patens Reveals Protein Macrocompartmentation and Microcompartmentation
2014 PLANT PHYSIOLOGY, Band: 164, Nummer: 4, Seiten: 2081 - 2095
KurzfassungExtant eukaryotes are highly compartmentalized and have integrated endosymbionts as organelles, namely mitochondria and plastids in plants. During evolution, organellar proteomes are modified by gene gain and loss, by gene subfunctionalization and neofunctionalization, and by changes in protein targeting. To date, proteomics data for plastids and mitochondria are available for only a few plant model species, and evolutionary analyses of high-throughput data are scarce. We combined quantitative proteomics, cross-species comparative analysis of metabolic pathways, and localizations by fluorescent proteins in the model plant Physcomitrella patens in order to assess evolutionary changes in mitochondrial and plastid proteomes. This study implements data-mining methodology to classify and reliably reconstruct subcellular proteomes, to map metabolic pathways, and to study the effects of postendosymbiotic evolution on organellar pathway partitioning. Our results indicate that, although plant morphologies changed substantially during plant evolution, metabolic integration of organelles is largely conserved, with exceptions in amino acid and carbon metabolism. Retargeting or regulatory subfunctionalization are common in the studied nucleus-encoded gene families of organelle-targeted proteins. Moreover, complementing the proteomic analysis, fluorescent protein fusions revealed novel proteins at organelle interfaces such as plastid stromules (stroma-filled tubules) and highlight microcompartments as well as intercellular and intracellular heterogeneity of mitochondria and plastids. Thus, we establish a comprehensive data set for mitochondrial and plastid proteomes in moss, present a novel multilevel approach to organelle biology in plants, and place our findings into an evolutionary context.
Mueller SJ, Lang D, Hoernstein SNW, Lang EGE, Schuessele C, Schmidt A, Fluck M, Leisibach D, Niegl C, Zimmer AD, Schlosser A, Reski R
Quantitative analysis of the mitochondrial and plastid proteomes of the moss Physcomitrella patens reveals protein macrocompartmentation and microcompartmentation
2014 Plant Physiol, Band: 164, Seiten: 2081 - 2095
Spiegelhalder K, Regen W, ..., Hennig J, Riemann D
Reduced anterior internal capsule white matter integrity in primary insomnia
2014 HUMAN BRAIN MAPPING, Band: 35, Nummer: 7, Seiten: 3431 - 3438
KurzfassungChronic insomnia is one of the most prevalent central nervous system diseases, however, its neurobiology is poorly understood. Up to now, nothing is known about the integrity of white matter tracts in insomnia patients. In this study, diffusion tensor imaging (DTI) was used in a well-characterized sample of primary insomnia (PI) patients and good sleeper controls to fill this void. Voxelwise between-group comparisons of fractional anisotropy (FA) were performed in 24 PI patients (10 males; 14 females; 42.7 +/- 14.5 years) and 35 healthy good sleepers (15 males; 20 females; 40.1 +/- 9.1 years) with age and sex as covariates. PI patients showed reduced FA values within the right anterior internal capsule and a trend for reduced FA values in the left anterior internal capsule. The results suggest that insomnia is associated with a reduced integrity of white matter tracts in the anterior internal capsule indicating that disturbed fronto-subcortical connectivity may be a cause or consequence of the disorder. Hum Brain Mapp 35:3431-3438, 2014. (c) 2013 Wiley Periodicals, Inc.
Tanimura Y
Reduced hierarchical equations of motion in real and imaginary time: Correlated initial states and thermodynamic quantities.
2014 J Chem Phys, Band: 141, Nummer: 4, Seiten: 044114 - 044114
Mohseni F, Mendoza M, Succi S, Herrmann H
Relativistic effects on the Richtmyer-Meshkov instability
2014 PHYSICAL REVIEW D, Band: 90, Nummer: 12
KurzfassungAn investigation of the relativistic effects on the Richtmeyer-Meshkov (RM) instability is presented. It is found that the relativistic effects weaken the RM instability as compared to the nonrelativistic case, both in two and three spatial dimensions. Linear stability is studied analytically and compared with numerical results in the linear growth regime. Finally, based on the numerical results, a general expression characterizing the nonlinear evolution of the instability is proposed.
Herbst M, Maclaren J, ..., Korvink J, Hennig J, Zaitsev M
Reproduction of Motion Artifacts for Performance Analysis of Prospective Motion Correction in MRI
2014 MAGNETIC RESONANCE IN MEDICINE, Band: 71, Nummer: 1, Seiten: 182 - 190
KurzfassungPurpose Despite numerous publications describing the ability of prospective motion correction to improve image quality in magnetic resonance imaging of the brain, a reliable approach to assess this improvement is still missing. A method that accurately reproduces motion artifacts correctable with prospective motion correction is developed, and enables the quantification of the improvements achieved. MethodsA software interface was developed to simulate rigid body motion by changing the scanning coordinate system relative to the object. Thus, tracking data recorded during a patient scan can be used to reproduce the prevented motion artifacts on a volunteer or a phantom. The influence of physiological motion on image quality was investigated by filtering these data. Finally, the method was used to reproduce and quantify the motion artifacts prevented in a patient scan. ResultsThe accuracy of the method was tested in phantom experiments and in vivo. The calculated quality factor, as well as a visual inspection of the reproduced artifacts shows a good correspondence to the original. ConclusionPrecise reproduction of motion artifacts assists qualification of prospective motion correction strategies. The presented method provides an important tool to investigate the effects of rigid body motion on a wide range of sequences, and to quantify the improvement in image quality through prospective motion correction. Magn Reson Med 71:182-190, 2014. (c) 2013 Wiley Periodicals, Inc.
Kauzlaric D, Dynowski M, Pastewka L, Greiner A, Korvink J
SYMPLER: SYMbolic ParticLE simulatoR with grid-computing interface
2014 COMPUTER PHYSICS COMMUNICATIONS, Band: 185, Nummer: 3, Seiten: 1085 - 1099
KurzfassungWe present the main design concepts of the object-oriented particle dynamics code SYMPLER. With this freely available software, simulations can be performed ranging from microscopic classical molecular dynamics up to the Lagrangian particle-based discretisation of macroscopic continuum mechanics equations. We show how the runtime definition of arbitrary degrees of freedom and of arbitrary equations of motion allows for modular and symbolic computation with high flexibility. Arbitrary symbolic expressions for inter-particle forces can be defined as well as fluxes of arbitrarily many additional scalar, vectorial or tensorial degrees of freedom. The integration in a high performance grid computing environment makes huge geographically distributed computational resources accessible to the software by an easy-to-use interface. Program summary Program title: SYMPLER Catalogue identifier: AERQ_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AERQ_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: GNU General Public License, version 3 No. of lines in distributed program, including test data, etc.: 221255 No. of bytes in distributed program, including test data, etc.: 1805954 Distribution format: tar.gz Programming language: C++. Computer: Any system operatable with Linux. Operating system: Linux, MacOS. Has the code been vectorised or parallelised?: Experimental OpenMP parallelisation for usually up to 8 cores, the grid-version can use hundreds of cores. RAM: tens of MB to several GB, depending on problem. Classification: 7.7, 12, 16.1, 16.3, 16.13, 23. External routines: GSL, libxmI2; optional: Iibsdl, OpenMP, libjama, libtnt, libsuperlu Nature of problem: A unified flexible and modular simulation tool allowing for the investigation of structural, thermodynamic, and dynamical properties of fluids and solids from microscopic over mesoscopic up to macroscopic time and length scales with suitable particle based simulation methods such as molecular dynamics, dissipative particle dynamics or smoothed particle hydrodynamics. The user should be enabled to freely define his own physical models without the need for recoding or code extensions. Solution method: SYMPLER provides flexibility to the user by 1. a modular object oriented structure that is passed to the user level and allows easy switching among different integration algorithms, particle interaction forces, boundary conditions, etc. 2. an arbitrary number of particle-species for the simulation of complex multi-component systems 3. an arbitrary number of additional user-defined degrees of freedom per particle-species 4. symbolic definition of runtime-compiled mathematical expressions for particle interactions 5. import of CAD-geometries 6. a flexible choice of available computational cores through a grid-computing interface, amongst others. Restrictions: Classical deterministic and stochastic Newtonian dynamics. Unusual features: Symbolic runtime-compiled user-defined expressions. Additional comments: The current version and all future updates to the code are also found at http://sympler.org. Running time: Some benchmarks are given in the paper. The running time is problem dependent and ranges from seconds to days. (C) 2013 Elsevier B.V. All rights reserved.
Toelle F, Gamp K, Muelhaupt R
Scale-up and purification of graphite oxide as intermediate for functionalized graphene
2014 CARBON, Band: 75, Seiten: 432 - 442
KurzfassungHigh purity graphite oxide (GO) and scale-up of GO synthesis is in high demand for enabling GO applications in catalysis and the synthesis of functionalized carbon nanomaterials. Although Hummers method, which involves oxidizing graphite with KMnO4 in sulfuric acid, is highly attractive with respect to its cost-effective raw materials and low energy demand, still purification, scale-up and safety problems prompt numerous challenges in large scale production. Conventional dead-end-filtration (DE) is difficult, owing to the severe plugging of the filters by water-swollen GO, whereas dialysis requires massive amounts of water. Plugging problems are solved when using membrane separation with average membrane pores smaller than the lateral micrometer dimensions of GO nanoplatelets. In contrast to DE and dialysis, a short DE prefiltration of acidified GO dispersions, combined with subsequent cross-flow filtration (CF) enables easy GO scale-up and production of high purity GO. Equipped with on-line monitoring of waste-water, this CF process is automated and enables concentration of GO dispersions in the final stage. In GO purification, pH switching represents the key to removing Mn and S impurities. (C) 2014 Elsevier Ltd. All rights reserved.
Delgado-Alvarez DL, Bartnicki-Garcia S, Seiler S, Mourino-Perez RR
Septum development in Neurospora crassa: the septal actomyosin tangle.
2014 Plos One, Band: 9, Nummer: 5, Seiten: e96744 - e96744
Jagle S, Ronsch K, Timme S, Andrlova H, Bertrand M, Jager M, Proske A, Schrempp M, Yousaf A, Michoel T, Zeiser R, Werner M, Lassmann S, Hecht A
Silencing of the EPHB3 tumor-suppressor gene in human colorectal cancer through decommissioning of a transcriptional enhancer.
2014 P Natl Acad Sci Usa, Band: 111, Nummer: 13, Seiten: 4886 - 4891
Baglioni C, Nanovska S, Regen W, Spiegelhalder K, Feige B, Nissen C, Reynolds C, Riemann D
Sleep and psychiatric disorders: a meta-analysis of the last 20 years of research
2014 JOURNAL OF SLEEP RESEARCH, Band: 23, Nummer: 1, SI
Baglioni C, ..., Spiegelhalder K, Feige B, Nissen C, Riemann D
Sleep changes. in the disorder of insomnia: A meta-analysis of polysomnographic studies
2014 SLEEP MEDICINE REVIEWS, Band: 18, Nummer: 3, Seiten: 195 - 213
KurzfassungInsomnia is a highly prevalent health problem worldwide. Primary insomnia (PI), i.e., insomnia not due to another disorder or substance use, represents a model to elucidate the pathophysiology of sleep. However, prior research in patients with PI has failed to demonstrate consistent abnormalities in the state-of-the-art assessment of sleep (polysomnography). The aim of this meta-analysis was to clarify whether there are identifiable polysomnographic sleep changes that correspond to the subjective complaints of patients with PI. Medline and Psyclnfo databases were searched from 1994 to 2012. Effects were calculated as standardized mean differences. Studies were pooled with the random-effects meta-analytic model. Twenty-three studies met inclusion criteria. In total, 582 patients with PI and 485 good sleeper controls (GSC) were evaluated. The results showed that patients with PI present a disruption of sleep continuity and a significant reduction of slow wave sleep (SWS) and rapid eye movement (REM) sleep compared to GSC. The observed changes in sleep architecture, i.e., reductions in SWS and REM sleep, hitherto did not count among the typical polysomnographic findings in patients with PI. An advanced knowledge of the polysomnographic changes in PI may add to foster the understanding of the pathophysiology of sleep and its bi-directional relationships with somatic and mental disorders. (C) 2013 Elsevier Ltd. All rights reserved.
Scholak T, Wellens T, Buchleitner A
Spectral backbone of excitation transport in ultracold Rydberg gases
2014 PHYSICAL REVIEW A, Band: 90, Nummer: 6
KurzfassungThe spectral structure underlying excitonic energy transfer in ultracold Rydberg gases is studied numerically, in the framework of random matrix theory, and via self-consistent diagrammatic techniques. Rydberg gases are made up of randomly distributed, highly polarizable atoms that interact via strong dipolar forces. Dynamics in such a system is fundamentally different from cases in which the interactions are of short range, and is ultimately determined by the spectral and eigenvector structure. In the energy levels’ spacing statistics, we find evidence for a critical energy that separates delocalized eigenstates from states that are localized at pairs or clusters of atoms separated by less than the typical nearest-neighbor distance. We argue that the dipole blockade effect in Rydberg gases can be leveraged to manipulate this transition across a wide range: As the blockade radius increases, the relative weight of localized states is reduced. At the same time, the spectral statistics, in particular, the density of states and the nearest-neighbor level-spacing statistics, exhibits a transition from approximately a 1-stable Levy to a Gaussian orthogonal ensemble. Deviations from random matrix statistics are shown to stem from correlations between interatomic interaction strengths that lead to an asymmetry of the spectral density and profoundly affect localization properties. We discuss approximations to the self-consistent Matsubara-Toyozawa locator expansion that incorporate these effects.
Rudnicki L, Puchala Z, Zyczkowski K
Strong majorization entropic uncertainty relations
2014 PHYSICAL REVIEW A, Band: 89, Nummer: 5
KurzfassungWe analyze entropic uncertainty relations in a finite-dimensional Hilbert space and derive several strong bounds for the sum of two entropies obtained in projective measurements with respect to any two orthogonal bases. We improve the recent bounds by Coles and Piani [P. Coles and M. Piani, Phys. Rev. A 89, 022112 (2014)], which are known to be stronger than the well-known result of Maassen and Uffink [ H. Maassen and J. B. M. Uffink, Phys. Rev. Lett. 60, 1103 (1988)]. Furthermore, we find a bound based on majorization techniques, which also happens to be stronger than the recent results involving the largest singular values of submatrices of the unitary matrix connecting both bases. The first set of bounds gives better results for unitary matrices close to the Fourier matrix, while the second one provides a significant improvement in the opposite sectors. Some results derived admit generalization to arbitrary mixed states, so that corresponding bounds are increased by the von Neumann entropy of the measured state. The majorization approach is finally extended to the case of several measurements.
Lu C, Prada-Gracia D, Rao F
Structure and dynamics of water in crowded environments slows down peptide conformational changes.
2014 J Chem Phys, Band: 141, Nummer: 4, Seiten: 045101 - 045101
Schaeffer U, Baumeister R, Schulze E
Targeted Purification of SnAvi-Tagged Proteins
2014 PROTEIN AFFINITY TAGS: METHODS AND PROTOCOLS, Band: 1177, Seiten: 163 - 174
KurzfassungTandem affinity purification (TAP) is a powerful technique to identify protein complex members. The modular composition of TAP-tags allows two sequential protein enrichment steps and thereby drastically reduces the amount of contaminants. Here, we describe the application of the SnAvi-tag-a TAP-tag useful in different expression systems. Due to its modular composition, this tag is multifunctional and facilitates among others the in vivo visualization of tagged proteins and their cell type specific activation.
Frei E, Schaadt A, Ludwig T, Hillebrecht H, Krossing I
The Influence of the Precipitation/Ageing Temperature on a Cu/ZnO/ZrO2 Catalyst for Methanol Synthesis from H-2 and CO2
2014 CHEMCATCHEM, Band: 6, Nummer: 6, Seiten: 1721 - 1730
KurzfassungFor heterogeneous catalysts, the constitution of the precursor is an important parameter to adjust the properties of the active catalyst. Therefore, we examined the influence of the temperature during the precipitation process and during the ageing time in the mother liquor for a Cu/ZnO/ZrO2 catalyst system obtained through a coprecipitation route. The variation of the temperature affects the ratio and crystallinity of the precursor phases zincian malachite and aurichalcite, as detected by powder XRD (phase and line width) and FTIR spectroscopy (characteristic asymmetric C-O stretching modes of the carbonate anions at (v) over tilde = 1600-1100 cm(-1)). Therefore, the precatalyst surface area (A(s,BET)) and pore distribution are adjustable (i.e., A(s,BET) of 190 m(2)g(-1) was reached). The influence of the synthesis conditions on the catalysts activity for methanol production was analyzed and discussed up to the level of productivity/activity testing at 413/513 K and 40 bar total H-2/CO2 pressure. The best catalyst showed a methanol productivity of 9.16 mmol g(cat)(-1)h(-1) (513 K, 40 bar, and gas hourly space velocity=8000) and is better than an industrial catalyst tested under the same conditions (8.34 mmol g(cat)(-1)h(-1)). However, despite considerable differences in the precursor and precatalyst structure and morphology, their influence on the methanol productivity is only small. This demonstrates that the active catalyst is formed under reaction conditions.
Riquelme M, Bredeweg EL, ..., Ludwig S, Seiler S, et.al.
The Neurospora crassa exocyst complex tethers Spitzenkorper vesicles to the apical plasma membrane during polarized growth.
2014 Mol Biol Cell, Band: 25, Nummer: 8, Seiten: 1312 - 1326
Engelke R, Riede J, Hegermann J, Wuerch A, Eimer S, Dengjel J, Mittler G
The Quantitative Nuclear Matrix Proteome as a Biochemical Snapshot of Nuclear Organization
2014 JOURNAL OF PROTEOME RESEARCH, Band: 13, Nummer: 9, Seiten: 3940 - 3956
KurzfassungThe nuclear matrix (NM) is an operationally defined structure of the mammalian cell nucleus that resists stringent biochemical extraction procedures applied subsequent to Nucleus nuclease-mediated chromatin digestion of intact nuclei. This comprises removal of soluble biomolecules and chromatin by means of either detergent (US: lithium diiodosalicylate) or high salt (AS: ammonium sulfate, sodium chloride) treatment. So far, progress toward defining bona fide NM proteins has been hindered by the problem of distinguishing them from copurifying abundant contaminants and extraction-method-intrinsic precipitation artifacts. Here, we present a highly improved NM purification strategy, adding a FACS sorting step for efficient isolation of morphologically homogeneous lamin B positive NM specimens. SILAC-based quantitative proteome profiling of LIS-, AS-, or NaCI-extracted matrices versus the nuclear proteome together with rigorous statistical filtering enables the compilation of a high-quality catalogue of NM proteins commonly enriched among the three different extraction methods. We refer to this set of 272 proteins as the NM central proteome. Quantitative NM retention profiles for 2381 proteins highlight elementary features of nuclear organization and correlate well with immunofluorescence staining patterns reported in the Human Protein Atlas, demonstrating that the NM central proteome is significantly enriched in proteins exhibiting a nuclear body as well as nuclear speckle-like morphology.
Meister K, Duman JG, Xu Y, Devries AL, Leitner DM, Havenith M
The Role of Sulfates on Antifreeze Protein Activity.
2014 J Phys Chem B, Band: 118, Nummer: 28, Seiten: 7920 - 7924
Dumit VI, Dengjel J
The cup of youth.
2014 Cell Cycle, Band: 13, Nummer: 13, Seiten: 2021 - 2021
Alexandrov A, Leurent S, Tsuboi Z, Zabrodin A
The master T-operator for the Gaudin model and the KP hierarchy
2014 Nucl Phys B, Band: 883, Seiten: 173 - 223
Has C, Kiritsi D, ..., Bruckner-Tuderman L
The missense mutation p.R1303Q in type XVII collagen underlies junctional epidermolysis bullosa resembling Kindler syndrome.
2014 J Invest Dermatol, Band: 134, Nummer: 3, Seiten: 845 - 849
Maity PC, Yang J, Klaesener K, Reth M
The nanoscale organization of the B lymphocyte membrane.
2014 Biochim Biophys Acta
Neumann J, Boerries M, ..., Busch H, Li-Weber M
The natural anticancer compound rocaglamide selectively inhibits the G1-S-phase transition in cancer cells through the ATM/ATR-mediated Chk1/2 cell cycle checkpoints
2014 INTERNATIONAL JOURNAL OF CANCER, Band: 134, Nummer: 8, Seiten: 1991 - 2002
KurzfassungTargeting the cancer cell cycle machinery is an important strategy for cancer treatment. Cdc25A is an essential regulator of cycle progression and checkpoint response. Over-expression of Cdc25A occurs often in human cancers. In this study, we show that Rocaglamide-A (Roc-A), a natural anticancer compound isolated from the medicinal plant Aglaia, induces a rapid phosphorylation of Cdc25A and its subsequent degradation and, thereby, blocks cell cycle progression of tumor cells at the G1-S phase. Roc-A has previously been shown to inhibit tumor proliferation by blocking protein synthesis. In this study, we demonstrate that besides the translation inhibition Roc-A can induce a rapid degradation of Cdc25A by activation of the ATM/ATR-Chk1/Chk2 checkpoint pathway. However, Roc-A has no influence on cell cycle progression in proliferating normal T lymphocytes. Investigation of the molecular basis of tumor selectivity of Roc-A by a time-resolved microarray analysis of leukemic vs. proliferating normal T lymphocytes revealed that Roc-A activates different sets of genes in tumor cells compared with normal cells. In particular, Roc-A selectively stimulates a set of genes responsive to DNA replication stress in leukemic but not in normal T lymphocytes. These findings further support the development of Rocaglamide for antitumor therapy.
Rosales-Mendoza S, Orellana-Escobedo L, Romero-Maldonado A, Decker E, Reski R
The potential of Physcomitrella patens as a platform for the production of plant-based vaccines
2014 EXPERT REVIEW OF VACCINES, Band: 13, Nummer: 2, Seiten: 203 - 212
KurzfassungThe moss Physcomitrella patens has a number of advantages for the production of biopharmaceuticals, including: i) availability of standardized conditions for cultivation in bioreactors; ii) not being part of the food chain; iii) high biosafety; iv) availability of highly efficient transformation methods; v) a haploid, fully sequenced genome providing genetic stability and uniform expression; vi) efficient gene targeting at the nuclear level allows for the generation of mutants with specific post-translational modifications (e.g., glycosylation patterns); and vii) oral formulations are a viable approach as no toxic effects are attributed to ingestion of this moss. In the light of this panorama, this opinion paper analyzes the possibilities of using P. patens for the production of oral vaccines and presents some specific cases where its use may represent significant progress in the field of plant-based vaccine development. The advantages represented by putative adjuvant effects of endogenous secondary metabolites and producing specific glycosylation patterns are highlighted.
Miettinen K, Dong L, ..., Werck-Reichhart D
The seco-iridoid pathway from Catharanthus roseus.
2014 Nat Commun, Band: 5
Scholz F, Himmel D, Eisele L, Unkrig W, Krossing I
The superacid HBr/AlBr(3) : protonation of benzene and ordered crystal structure of [C(6)H(7)](+)[Al(2)Br(7)](-).
2014 Angew Chem Int Edit, Band: 53, Nummer: 6, Seiten: 1689 - 1692
MacKenzie R, Goeritz A, Greedy S, von Hauff E, Nelson J
Theory of Stark spectroscopy transients from thin film organic semiconducting devices
2014 PHYSICAL REVIEW B, Band: 89, Nummer: 19
KurzfassungHerein, we propose a model to describe picosecond-nanosecond charge separation and nongeminate recombination in organic semiconductors. The model is used to explain time-resolved electroabsorption (EA) measurements performed on diodes made from phenyl-C61-butyric acid methyl ester. We find that the measured shape of the EA transient is due to a combination of microscopic carrier dynamic effects such as carrier trapping, as well as macroscopic effects such as band bending caused by the nonuniform poloron generation profile across the device. We demonstrate that the initial fast phase of the EA transient is due to hot free carriers being able to move freely within the device; over time these hot free carriers cool and become trapped giving rise to the second slower phase of the transient. We further show that the commonly observed dependence of the EA signal on probe wavelength can be explained in terms of the spatial overlap of electrostatic potential within the device and the optical mode of the probe light. Finally, we discuss the implications of these results for pump-probe experiments on thin organic films.
Sommerlade L, Thiel M, Platt B, Plano A, Riedel G, Grebogi C, Mader Wolfgang, Mader Malenka, Timmer Jens, Schelter Bjoern
Time-Variant Estimation of Connectivity and Kalman’s Filter
2014 METHODS IN BRAIN CONNECTIVITY INFERENCE THROUGH MULTIVARIATE TIME SERIES ANALYSIS, Seiten: 161 - 177
Palma CA, Bjork J, Rao F, Kuehne D, Klappenberger F, Barth J
Topological Dynamics in Supramolecular Rotors
2014 NANO LETTERS, Band: 14, Nummer: 8, Seiten: 4461 - 4468
KurzfassungArtificial molecular switches, rotors, and machines are set to establish design rules and applications beyond their biological counterparts. Herein we exemplify the role of noncovalent interactions and transient rearrangements in the complex behavior of supramolecular rotors caged in a 2D metal-organic coordination network. Combined scanning tunneling microscopy experiments and molecular dynamics modeling of a supramolecular rotor with respective rotation rates matching with 0.2 kcal mol(-1) (9 meV) precision, identify key steps in collective rotation events and reconfigurations. We notably reveal that stereoisomerization of the chiral trimeric units entails topological isomerization whereas rotation occurs in a topology conserving, two-step asynchronous process. In supramolecular constructs, distinct displacements of subunits occur inducing a markedly lower rotation barrier as compared to synchronous mechanisms of rigid rotors. Moreover, the chemical environment can be instructed to control the system dynamics. Our observations allow for a definition of mechanical cooperativity based on a significant reduction of free energy barriers in supramolecules compared to rigid molecules.
Palme K, Li X, Teale W
Towards Second Green Revolution: Engineering Nitrogen Use Efficiency
2014 JOURNAL OF GENETICS AND GENOMICS, Band: 41, Nummer: 6, Seiten: 315 - 316
Alexandrov A, Mironov A, Morozov A
Towards matrix model representation of HOMFLY polynomials
2014 JETP LETTERS, Band: 100, Nummer: 4, Seiten: 271 - 278
KurzfassungWe investigate possibilities of generalizing the TBEM (Tierz, Brini-Eynard-Mario) eigenvalue matrix model, which represents the non-normalized colored HOMFLY polynomials for torus knots as averages of the corresponding characters. We look for a model of the same type, which is a usual Chern-Simons mixture of the Gaussian potential, typical for Hermitian models, and the sine Vandermonde factors, typical for the unitary ones. We mostly concentrate on the family of twist knots, which contains a single torus knot, the trefoil. It turns out that for the trefoil the TBEM measure is provided by an action of Laplace exponential on the Jones polynomial. This procedure can be applied to arbitrary knots and provides a TBEM-like integral representation for the N = 2 case. However, beyond the torus family, both the measure and its lifting to larger N contain non-trivial corrections in A = logq. A possibility could be to absorb these corrections into a deformation of the Laplace evolution by higher Casimir and/or cut-and-join operators, in the spirit of Hurwitz tau-function approach to knot theory, but this remains a subject for future investigation.
Mullineaux CW, Nurnberg DJ
Tracing the path of a prokaryotic paracrine signal.
2014 Mol Microbiol, Band: 94, Nummer: 6, Seiten: 1208 - 1212
Loffek S, Hurskainen T, Jackow J, Sigloch FC, Schilling O, Tasanen K, Bruckner-Tuderman L, Franzke CW
Transmembrane collagen XVII modulates integrin dependent keratinocyte migration via PI3K/Rac1 signaling.
2014 Plos One, Band: 9, Nummer: 2, Seiten: e87263 - e87263
Prauss K, Varatharajan R, Joseph K, Moser A
Transmitter self-regulation by extracellular glutamate in fresh human cortical slices
2014 JOURNAL OF NEURAL TRANSMISSION, Band: 121, Nummer: 11, Seiten: 1321 - 1327
KurzfassungGlutamate is thought to be the most important excitatory neurotransmitter in the CNS, while glutamine predominantly serves as a precursor and metabolite in the glutamate-glutamine cycle. To verify the interaction between intrinsic extracellular glutamate, y-aminobutyric acid (GABA) levels and glial glutamine outflow in human tissue, fresh brain slices from human frontal cortex were incubated in superfusion chambers in vitro. Human neocortical tissue was obtained during surgical treatment of subcortical brain tumors. For superfusion experiments, the white matter was separated and discarded from the gray matter, which finally contained all six neocortical layers. Outflows of endogenous glutamate, GABA and glutamine were established after a 40-min washout period and amounts were simultaneously quantified after two-phase derivatization by high-performance liquid chromatography with electrochemical detection. Under basal conditions, amounts of glutamate could be found 20-fold in comparison to the inhibitory neurotransmitter GABA, whereas this excitatory predominance markedly declined after veratridine-induced activation. The basal glutamate:glutamine ratio of extracellular levels was approximately 1:2. Blockade or activation of the voltage-gated sodium channel by tetrodotoxin or veratridine significantly modulated glutamate levels, but the glutamate:glutamine ratio was nearly constant with 1:2. When the EAAT blocker TBOA was employed, glutamine remained nearly unchanged whereas glutamate significantly enhanced. These results led us to suggest that glutamine release through glial SN1 is related to EAAT activity that can be modulated by intrinsic extracellular glutamate in human cortical slices.
More S, Choudhary S, Higelin A, Krossing I, Melle-Franco M, Mateo-Alonso A
Twisted pyrene-fused azaacenes
2014 CHEMICAL COMMUNICATIONS, Band: 50, Nummer: 16, Seiten: 1976 - 1979
KurzfassungAn approach for introducing twists in pyrene-fused azaacenes is reported. Depending on the volume and the rigidity of the silyl groups, different-sized twist angles, which oscillate between 4 degrees and 24 degrees, are induced along the longitudinal conjugated backbone.
Tregnago G, Flechon C, Choudhary S, Gozalvez C, Mateo-Alonso A, Cacialli F
Virtually pure near-infrared electroluminescence from exciplexes at polyfluorene/hexaazatrinaphthylene interfaces
2014 APPLIED PHYSICS LETTERS, Band: 105, Nummer: 14
KurzfassungElectronic processes at the heterojunction between chemically different organic semiconductors are of special significance for devices such as light-emitting diodes (LEDs) and photovoltaic diodes. Here, we report the formation of an exciplex state at the heterojunction of an electron-transporting material, a functionalized hexaazatrinaphthylene, and a hole-transporting material, poly(9,9-dioctylfluorene-alt-N-(4-butylphenyl)diphenylamine) (TFB). The energetics of the exciplex state leads to a spectral shift of similar to 1 eV between the exciton and the exciplex peak energies (at 2.58 eV and 1.58 eV, respectively). LEDs incorporating such bulk heterojunctions display complete quenching of the exciton luminescence, and a nearly pure near-infrared electroluminescence arising from the exciplex (at similar to 1.52 eV) with >98% of the emission at wavelengths above 700 nm at any operational voltage. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.
Qi J, Asl HF, Bjorkegren J, Michoel T
kruX: matrix-based non-parametric eQTL discovery.
2014 Bmc Bioinformatics, Band: 15, Seiten: 11 - 11

Buchbeiträge

Jahre: 2014

zurück zur Übersicht aller Publikationen

2014

Wehkamp N, Sivasubramanian N, Kauzlaric D, Pavlov L, Slat B, Sonneville J
How the oceans can clean themselves -- a feasibility study
In: Ther Ocean Cleanup
2014, Ther Ocean Cleanup, Seiten: 178 - 195,

Konferenzbeiträge

Jahre: 2014

zurück zur Übersicht aller Publikationen

2014

Li L, Liu L, Tabata O, Li W
Elasticity measurement of DNA origami nanotube in liquid with tapping mode AFM
2014 2014 9TH IEEE INTERNATIONAL CONFERENCE ON NANO/MICRO ENGINEERED AND MOLECULAR SYSTEMS (NEMS), Seiten: 684 - 687
KurzfassungThe elasticity of nanomaterial is extremely difficult to be obtained with traditional method due to their ultra-small scale. AFM provide a feasible way to solve this problem, but it still meets many challenges especially for the measurement of one dimensional material such as DNA origami nanotube, CNT, Silicon Nanowire and so on. In addition to the influence aroused from the sample surface effect, locating the probe exactly over the 1D material with nano-diameter is hard to achieve due to the nonlinearity of PZT actuator and the thermal drift. In this study, a new method is proposed to overcome these shortcomings. It is a physical calculation process combined with experimental measurement results to deduce the elasticity of one dimensional material. This method starts at an assumed elasticity of nanomaterials, and then experimental elasticity can be obtained based on scanned image in tapping mode. The elasticity with minimized error between assumed one and experimental one should be the true value of the materials. Since with the imaging scan method, the exactly locating the probe over the sample is not necessary. In addition, due to accurately controllable tapping force, the deformation of the nanomaterial can be controlled within a tiny scale, thus the influence from the sample surface effect can be get rid of effectively. The elasticity (pre-known) of polystyrene is measured to demonstrate the effectiveness of the proposed method. The elasticity of DNA origami is also first time obtained with the proposed method, which shows an elasticity range between 75MPa and 180 MPa. This method is simple and can be used to measure other soft nano-materials.
Beigelbeck R, Reyes-Romero D, Cerimovic S, Kohl F, Voglhuber-Brunnmaier T, Jakoby B, Urban G
Frequency Domain Based Measurement Method for the Thermal Parameters of a Thin-Film Diaphragm Embedded in a MEMS Multi-Parameter Wind Sensor
2014 28TH EUROPEAN CONFERENCE ON SOLID-STATE TRANSDUCERS (EUROSENSORS 2014), Band: 87, Seiten: 632 - 635
KurzfassungWe report on a novel method to determine the thermal conductivity, thermal diffusivity, and average emissivity of a thin-film diaphragm embedded in a MEMS multi-parameter wind sensor. Compared to other measurement techniques for thermal thin-film parameters, our method does not require fabrication of custom specimens. The results can be obtained from frequency response measurements directly carried out on the wind sensor. We describe the theoretical background of this method, provide an efficient analytical model (validated by FEM simulations) for the parameter extraction from the raw measurement data, and demonstrate its application by sample measurements performed on multi-layer SixNy-SiO2 thin-film diaphragms. (C) 2014 The Authors. Published by Elsevier Ltd.