Publications by authors named "Markus Stein"

Intense phase-locked terahertz (THz) pulses are the bedrock of THz lightwave electronics, where the carrier field creates a transient bias to control electrons on sub-cycle time scales. Key applications such as THz scanning tunnelling microscopy or electronic devices operating at optical clock rates call for ultimately short, almost unipolar waveforms, at megahertz (MHz) repetition rates. Here, we present a flexible and scalable scheme for the generation of strong phase-locked THz pulses based on shift currents in type-II-aligned epitaxial semiconductor heterostructures.

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We measure both nonlinear absorption and nonlinear refraction in a ${{\rm CH}_3}{{\rm NH}_3}{{\rm PbBr}_3}$CHNHPbBr single crystal using the Z-scan technique with femtosecond laser pulses. At 1000 nm, we obtain values of 5.2 cm/GW and ${+}{9.

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Cesium lead halide perovskites are of interest for light-emitting diodes and lasers. So far, thin-films of CsPbX have typically afforded very low photoluminescence quantum yields (PL-QY < 20%) and amplified spontaneous emission (ASE) only at cryogenic temperatures, as defect related nonradiative recombination dominated at room temperature (RT). There is a current belief that, for efficient light emission from lead halide perovskites at RT, the charge carriers/excitons need to be confined on the nanometer scale, like in CsPbX nanoparticles (NPs).

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The purpose of this study was to determine if self-reported characteristics of social cohesion and local neighborhood safety positively affect the mental health of their residents, regardless of individual characteristics. A sample of participants in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) baseline was used. The Clinical Interview Schedule-Revised (CIS-R) instrument was used for tracking common mental disorders (CMD).

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The serine/threonine kinase Par1 is a core component of the machinery that sets up polarity in the embryo and regulates cell fate decisions but its role in the homeostasis of adult tissues is poorly understood. Inhibition of Par1 by the bacterium Helicobacter pylori (H. pylori) represents the only established pathology that affects Par1 function in an adult epithelium.

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(Ga,In)As/GaAs/Ga(As,Sb) and (Ga,In)As/GaAs/Ga(N,As) type-II double quantum well heterostructures have been grown by metal-organic vapor phase epitaxy. A growth interruption procedure was used to intentionally modify the morphology of the internal interfaces. The heterostructures were investigated using continuous wave and time-resolved photoluminescence as well as optical pump-optical probe spectroscopy.

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Matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF MS) is commonly used by clinical microbiology laboratories to identify bacterial pathogens and yeasts, but not for the identification of moulds. Recent progress in extraction protocols and the composition of comparative libraries support potential application of MALDI-TOF MS for mould identification in clinical microbiology laboratories. We evaluated the performance of the Bruker Microflex™ MALDI-TOF MS instrument (Billerica, MA, USA) to identify clinical isolates and reference strains of moulds using 3 libraries, the Bruker mould library, the National Institutes of Health (NIH) library and the Mass Spectrometry Identification (MSI) online library, and compared those results to conventional (morphological) and molecular (18S/ITS; gold standard) identification methods.

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Background: N-chlorotaurine (NCT), a long-lived oxidant produced by human leukocytes, can be synthesized chemically and used topically as a well-tolerated antiseptic to different body regions including sensitive ones. The aim of this study was to test the tolerability of inhaled 1% NCT in aqueous solution upon repeated application.

Methods: The study was performed double-blind and randomized with a parallel test group (1% NCT) and control group (0.

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Intravesical Bacillus Camlette-Guérin (BCG) is the treatment of choice for non-muscle invasive bladder cancer, and has been used successfully for over 40 years. A rare and potentially fatal complication of intravesical BCG therapy is BCG-induced sepsis. We report a rare case in which a patient with end-stage renal disease secondary to chronic granulomatous interstitial nephritis underwent remote, pre-transplant intravesical BCG treatment for high-grade non-invasive papillary bladder carcinoma.

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The current consensus report was compiled under the patronage of the Austrian Society of Pneumology (Österreichischen Gesellschaft für Pneumologie, ÖGP) with the intention of providing practical guidelines for out-of-hospital ventilation that are in accordance with specific Austrian framework parameters and legal foundations. The guidelines are oriented toward a 2004 consensus ÖGP recommendation concerning the setup of long-term ventilated patients and the 2010 German Respiratory Society S2 guidelines on noninvasive and invasive ventilation of chronic respiratory insufficiency, adapted to national experiences and updated according to recent literature. In 11 chapters, the initiation, adjustment, and monitoring of out-of-hospital ventilation is described, as is the technical equipment and airway access.

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CagA is a multifunctional toxin of Helicobacter pylori that is secreted into host epithelial cells by a type IV secretion system. Following host cell translocation, CagA interferes with various host-cell signalling pathways. Most notably this toxin is involved in the disruption of apical-basolateral cell polarity and cell adhesion, as well as in the induction of cell proliferation, migration and cell morphological changes.

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Helicobacter pylori colonizes the gastric mucosa of more than 50% of the human population, causing chronic inflammation, which however is largely asymptomatic. Nevertheless, H. pylori-infected subjects can develop chronic gastritis, peptic ulcer, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer.

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Background: Helicobacter pylori is pathogenic bacterium that is associated with several gastric diseases in humans. Disease is characterized by severe inflammatory responses is the stomach that are induced by various chemokines and cytokines. Previous reports indicated that some of these responses are mediated through Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling.

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Lipopolysaccharide (LPS) is a major component on the surface of Gram negative bacteria and is composed of lipid A-core and the O antigen polysaccharide. O polysaccharides of the gastric pathogen Helicobacter pylori contain Lewis antigens, mimicking glycan structures produced by human cells. The interaction of Lewis antigens with human dendritic cells induces a modulation of the immune response, contributing to the H.

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The CagA protein of Helicobacter pylori interacts with numerous cellular factors and is associated with increased virulence and risk of gastric carcinoma. We present here the cocrystal structure of a subdomain of CagA with the human kinase PAR1b/MARK2, revealing that a CagA peptide mimics substrates of this kinase family, resembling eukaryotic protein kinase inhibitors. Mutagenesis of conserved residues central to this interaction renders CagA inactive as an inhibitor of MARK2.

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Amphotericin B (AMB) concentrations were determined in pulmonary epithelial lining fluid (ELF) of 44 critically ill patients, who were receiving treatment with liposomal AMB (LAMB) (n = 11), AMB colloidal dispersion (ABCD) (n = 28), or AMB lipid complex (ABLC) (n = 5). Mean AMB levels (+/- standard errors of the means) in ELF amounted to 1.60 +/- 0.

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Pathogenic strains of Helicobacter pylori use a type IV secretion system (T4SS) to deliver the toxin CagA into human host cells. The T4SS, along with the toxin itself, is coded into a genomic insert, which is termed the cag pathogenicity island. The cag pathogenicity island contains about 30 open-reading frames, for most of which the exact function is not well characterized or totally unknown.

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Helicobacter pylori is a gram-negative pathogen that colonizes the stomachs of over half the world's population and causes a spectrum of gastric diseases including gastritis, ulcers, and gastric carcinoma. The H. pylori species exhibits unusually high levels of genetic variation between strains.

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To expand our knowledge of Helicobacter pylori virulence mechanisms, we used iTRAQ (isobaric tagging reagents for relative and absolute quantification)-based proteomic analysis to investigate the effect of H. pylori on gastric AGS tissue culture cells. In particular, we were interested in finding out which effects of H.

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Helicobacter pylori exists in 2 distinct morphological states, helicoid and coccoid. Both have been observed in in vitro culture and in gastric biopsies. We visualized H.

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