1,576 results match your criteria: "J.W. Goethe-Universitat[Affiliation]"

Bound-State Beta Decay of ^{205}Tl^{81+} Ions and the LOREX Project.

Phys Rev Lett

December 2024

Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Zellescher Weg 19, 01062 Dresden, Germany.

Stable ^{205}Tl ions have the lowest known energy threshold for capturing electron neutrinos (ν_{e}) of E_{ν_{e}}≥50.6  keV. The Lorandite Experiment (LOREX), proposed in the 1980s, aims at obtaining the longtime averaged solar neutrino flux by utilizing natural deposits of Tl-bearing lorandite ores.

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[Non-clear cell renal cell carcinoma].

Urologie

December 2024

Medizinische Klinik II, Universitätsklinik, J.W. Goethe Universität, Theodor-Stern-Kai 7, 60590, Frankfurt/Main, Deutschland.

Non-clear cell renal cell carcinomas (nccRCC) account for approximately 20-25% of renal cell carcinomas. Approximately 20 different histologically and/or molecularly defined entities are subsumed under nccRCC. Many entities only have a share of 1% or less.

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High-temperature Tl decay clarifies Pb dating in early Solar System.

Nature

November 2024

GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany.

Article Synopsis
  • Radioactive nuclei that live for millions of years help us understand the Sun's formation and the nucleosynthesis happening when it was born, with lead (Pb) being a key example.
  • Recent measurements of the weak decay of ionized thallium (Tl) provided a more accurate half-life, which was found to be 4.7 times longer than previously thought, thus reducing uncertainty in our calculations.
  • Using these improved decay rates, researchers calculated lead yields in asymptotic giant branch (AGB) stars, confirmed isolation times for solar material, and validated the theory that the Sun formed in a long-lived molecular cloud.
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Huntington's disease (HD) is a devastating, incurable condition whose pathophysiological mechanism relies on mutant RNA CAG repeat expansions. Aberrant recruitment of RNA-binding proteins by mutant CAG hairpins contributes to the progress of neurodegeneration. In this work, we identified a novel binder based on an aurone scaffold that reduces the level of binding of HTT mRNA to the MID1 protein .

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The aim of this case report is to show the advantages of the extraperitoneal cesarean section (ECS) approach in a pregnant patient with multiple previous abdominal transperitoneal colon surgeries and Crohn's disease. A pregnant nulliparous woman with Crohn's disease was admitted for delivery. After delivery, a large rupture and lesion of the rectum was observed.

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Chiral 2-hydroxy acids and 2-hydroxy-4-butyrolactone derivatives are structural motifs often found in fine and commodity chemicals. Here, we report a tandem biocatalytic stereodivergent route for the preparation of these compounds using three stereoselective aldolases and two stereocomplementary ketoreductases using simple and achiral starting materials. The strategy comprises (i) aldol addition reaction of 2-oxoacids to aldehydes using two aldolases from , 3-methyl-2-oxobutanoate hydroxymethyltransferase (KPHMT ), 2-keto-3-deoxy-l-rhamnonate aldolase (YfaU ), and --hydroxybenzylidene pyruvate hydratase-aldolase from (HBPA ) and (ii) subsequent 2-oxogroup reduction of the aldol adduct by ketopantoate reductase from (KPR ) and a Δ-piperidine-2-carboxylate/Δ-pyrroline-2-carboxylate reductase from pv.

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Design of Aurone-Based Dual-State Emissive (DSE) Fluorophores.

Chemistry

May 2023

Inorganic Photoactive Materials, Institute of Inorganic Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany.

The development of dual-state emissive (DSE) fluorophores, i. e. organic molecules showing balanced emission in both solution and as molecular solids, has recently become an emerging approach in material science, biology, sensing, and optoelectronics.

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We investigate experimentally and theoretically the C and O 1s photoionization of fixed-in-space CO molecules at a photon energy of 905 eV. We find a significant dependence of the photoelectron angular distributions on the direction of propagation of the ionizing radiation. It results from an interplay of nondipole effects, on one hand, and molecular effects, on the other.

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Knowledge of the refractive index of water in the deeply supercooled metastable liquid state is important, for example, for an accurate description of optical reflection and refraction processes occurring in clouds. However, a measurement of both the temperature and wavelength dependence of the refractive index under such extreme conditions is challenging. Here, we employ Raman spectroscopy in combination with microscopic water jets in vacuum to obtain the refractive index of supercooled water to a lowest temperature of 230.

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The B-nucleophilic 9H-9-borafluorene dianion reacts with 9-chloro-9-silafluorene to afford air- and moisture-stable silylborate salts M[Ar (H)B-Si(H)Ar ] (M[HBSiH], M=Li, Na). Li[HBSiH] and Me SiCl give the B-pyridine adduct Ar (py)B-Si(H)Ar ((py)BSiH) or the chlorosilane Li[Ar (H)B-Si(Cl)Ar ] (Li[HBSiCl]) in C H -pyridine or THF. In both cases, the first step is H abstraction at the B center.

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The title compound, CHN·2CHO, was synthesized from the corres-ponding sterically crowded phenol by treatment with the aminal cage polyamine. Single-crystal X-ray diffraction structural analysis revealed the three-mol-ecule aggregate to crystallize in the monoclinic space group 2/ with one half of a 1,3,6,8-tetra-aztri-cyclo-[4.4.

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Femtosecond extreme ultraviolet wave packet interferometry (XUV-WPI) was applied to study resonant interatomic Coulombic decay (ICD) in the HeNe dimer. The high demands on phase stability and sensitivity for vibronic XUV-WPI of molecular-beam targets are met using an XUV phase-cycling scheme. The detected quantum interferences exhibit vibronic dephasing and rephasing signatures along with an ultrafast decoherence assigned to the ICD process.

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Synthesis and crystal structure of 2-(2-hy-droxy-phen-yl)-1,3-bis-(4-meth-oxy-benz-yl)-1,3-diazinan-5-ol.

Acta Crystallogr E Crystallogr Commun

July 2022

Institut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von Laue-Str. 7, 60438 Frankfurt/Main, Germany.

The redetermined structure of 2-(2-hy-droxy-phen-yl)-1,3-bis-(4-meth-oxy-benz-yl)-1,3-diazinan-5-ol, CHNO, at 173 K has ortho-rhom-bic () symmetry. It was previously described by Bolte [ Private Communication (refcode EWICEV). CCDC, Cambridge, England].

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Introduction: Transimpedance measurements from cochlear implant electrodes have the potential to identify anomalous electrode array placement, such as tip fold-over (TFO) or fold-back, basal electrode kinking, or buckling. Analysing transimpedance may thus replace intraoperative or post-operative radiological imaging to detect any potential misplacements. A transimpedance algorithm was previously developed to detect deviations from a normal electrode position with the aim of intraoperatively detecting TFO.

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How long does it take to emit an electron from an atom? This question has intrigued scientists for decades. As such emission times are in the attosecond regime, the advent of attosecond metrology using ultrashort and intense lasers has re-triggered strong interest on the topic from an experimental standpoint. Here, we present an approach to measure such emission delays, which does not require attosecond light pulses, and works without the presence of superimposed infrared laser fields.

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Three enzymatic routes toward γ-hydroxy-α-amino acids by tandem aldol addition-transamination one-pot two-step reactions are reported. The approaches feature an enantioselective aldol addition of pyruvate to various nonaromatic aldehydes catalyzed by --hydroxybenzylidene pyruvate hydratase-aldolase (HBPA) from . This affords chiral 4-hydroxy-2-oxo acids, which were subsequently enantioselectively aminated using -selective transaminases.

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Treatment options of locoregional recurrent head and neck squamous cell cancer (HNSCC) include both local strategies as surgery or re-radiotherapy and systemic therapy. In this prospective, multi-center, non-interventional study, patients were treated either with platinum-based chemotherapy and cetuximab (CT + Cet) or re-radiotherapy and cetuximab (RT + Cet). In the current analysis, progression-free survival (PFS) and overall survival (OS) were compared in patients with locoregional recurrence.

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Transcranial alternating-current stimulation (tACS) in the frequency range of 1-100 Hz has come to be used routinely in electroencephalogram (EEG) studies of brain function through entrainment of neuronal oscillations. It turned out, however, to be highly non-trivial to remove the strong stimulation signal, including its harmonic and non-harmonic distortions, as well as various induced higher-order artifacts from the EEG data recorded during the stimulation. In this paper, we discuss some of the problems encountered and present methodological approaches aimed at overcoming them.

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This work reports on synthesis and extensive experimental and theoretical investigations on photophysical, structural and thermal properties of the Ni and Cu discrete mononuclear homoleptic complexes [Ni( )] and [Cu( )] fabricated from the Schiff base dyes -HOCH-CH=N--CH (H ) and -HOCH-CH=N--CH (H ), containing the sterically crowding cyclo-hexyl units. The six-membered metallocycles adopt a clearly defined envelope conformation in [Ni( )], while they are much more planar in the structures of [Ni( )] and [Cu( )]. It has been demonstrated by in-depth bonding analyses based on the ETS-NOCV and Interacting Quantum Atoms energy-decomposition schemes that application of the bulky substituents, containing several C-H groups, has led to the formation of a set of classical and unintuitive intra- and inter-molecular interactions.

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Antiarrhythmic drugs for atrial fibrillation: lessons from the past and opportunities for the future.

Europace

April 2021

Cardiovascular and Cell Sciences Research Institute, Cardiology Clinical Academic Group, St George's, University of London, London, UK.

Atrial fibrillation (AF) remains a highly prevalent and troublesome cardiac arrhythmia, associated with substantial morbidity and mortality. Restoration and maintenance of sinus rhythm (rhythm-control therapy) is an important element of AF management in symptomatic patients. Despite significant advances and increasing importance of catheter ablation, antiarrhythmic drugs (AADs) remain a cornerstone of rhythm-control therapy.

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Multi-gene transformation methods need to be able to introduce multiple transgenes into plants in order to reconstitute a transgenic locus where the introduced genes express in a coordinated manner and do not segregate in subsequent generations. This simultaneous multiple gene transfer enables the study and modulation of the entire metabolic pathways and the elucidation of complex genetic control circuits and regulatory hierarchies. We used combinatorial nuclear transformation to produce multiplex-transgenic maize plants.

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1-(adamantane-1-carbonyl-3-(1-naphthyl)) thiourea (CHNOS (4), was synthesized by the reaction of freshly prepared adamantane-1-carbonyl chloride from corresponding acid (3) with ammonium thiocyanate in 1:1 M ratio in dry acetone to afford the adamantane-1-carbonyl isothiocyanate (2) in situ followed by treatment with 1-naphthyl amine (3). The structure was established by elemental analyses, FTIR, H, C NMR and mass spectroscopy. The molecular and crystal structure were determined by single crystal X-ray analysis.

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Geographical range evolution of the genus (Anura: Rhacophoridae) from the Oligocene to present.

Zool Res

January 2021

CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China.

Currently, the genus comprises 26 species distributed in South, Southeast, and East Asia. Because of their relatively low dispersal capability and intolerance to seawater, this genus is ideal for the study of terrestrial range evolution that extends into the island archipelagos of southeastern Asia. In this study, based on data compiled for from previous studies and partial mitochondrial and nuclear genes collected in this study, we performed systematic biogeographical analysis.

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