Numerical Simulation of Turbulent Swirling Flows

In this paper, turbulent swirling flow in circular pipe in the wake behind an axial fan is investigated by URANS and LES using two different CFD codes: SPARC, developed at Institute of Fluid Machinery, at Karlsruhe Institute of Technology and OpenFOAM. Results of simulations are compared with experimental results obtained with LDA measurement techniques in that flow field. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Fixed point theorems on ordered metric spaces and applications to nonlinear elastic beam equations

In this paper, we establish certain fixed point theorems in metric spaces with a partial ordering. Presented theorems extend and generalize several existing results in the literature. As application, we use the fixed point theorems obtained in this paper to study existence and uniqueness of solutions for fourth-order two-point boundary value problems for elastic beam equations.     

Quantitative estimation of ultrasound beam intensities using infrared thermography-Experimental validation

Infrared (IR) thermography is a technique that has the potential to rapidly and noninvasively determine the intensity fields of ultrasound transducers. In the work described here, IR temperature measurements were made in a tissue phantom sonicated with a high-intensity focused ultrasound (HIFU) transducer, and the intensity fields were determined using a previously published mathematical formulation relating intensity to temperature rise at a tissue/air interface. Intensity fields determined from the IR technique were compared with those derived from hydrophone measurements. Focal intensities and beam widths determined via the IR approach agreed with values derived from hydrophone measurements to within a relative difference of less than 10%, for a transducer with a gain of 30, and about 13% for a transducer with a gain of 60. At axial locations roughly 1 cm in front (pre-focal) and behind (post-focal) the focus, the agreement with hydrophones for the lower-gain transducer remained comparable to that in the focal plane. For the higher-gain transducer, the agreement with hydrophones at the pre-focal and post-focal locations was around 40%.     

High-resolution mass spectrometry and hydrogen/deuterium exchange study of mitorubrin azaphilones and nitrogenized analogues

Azaphilones represent numerous groups of wild fungal secondary metabolites that exhibit exceptional tendency to bind to nitrogen atoms in various molecules, especially those containing the amine group. Nitrogenized analogues of mitorubrin azaphilones, natural secondary metabolites of Hypoxylon fragiforme fungus, have been detected in the fungal methanol extract in very low concentrations. Positive electrospray ionization interfaced with high-resolution mass spectrometry was applied for confirmation of the elemental composition of protonated species. Collision-induced dissociation (CID) experiments have been performed, and fragmentation mechanisms have been proposed. Additional information regarding both secondary metabolite analogue families has been reached by application of gas-phase proton/deuterium (H/D) exchanges performed in the collision cell of a triple quadrupole mass spectrometer. An incomplete H/D exchange with one proton less than expected was observed for both protonated mitorubrin azaphilones and their nitrogenized analogues. By means of the density functional theory, an appropriate explanation of this behavior was provided, and it revealed some information concerning gas-phase H/D exchange mechanism and protonation sites. Copyright ? 2012 John Wiley & Sons, Ltd.     

Synthesis of highly cytotoxic tiazofurin mimics bearing a 2,3-anhydro function in the furanose ring

This paper describes a divergent de novo synthesis of 2-(2,3-anhydro-β-d-ribofuranosyl)thiazole-4-carboxamide (2′,3′-anhydro-tiazofurin) and the corresponding α- and β-homo-C-nucleosides. The synthetic approach was based on a multistep transformation of d-glucose into suitably protected aldonthioamides followed by their subsequent cyclocondensation with ethyl bromopyruvate to form the thiazole ring. Antiproliferative activity of the target molecules is reported against several human tumour cell lines.     

Separation of hypoviral double-stranded RNA on monolithic chromatographic supports

A procedure based on BIA Separations CIM DEAE anion-exchange chromatography was developed to separate double-stranded (ds) RNA of hypovirus infecting phytopathogenic fungus Cryphonectria parasitica. Using a linear gradient of 25 mM 4-morpholinepropanesulfonic acid (MOPS), pH 7.0 as a binding buffer, and 25 mM MOPS, 1.5 M NaCl, 0.1 mM EDTA, 15% isopropanol (v/v), pH 7.0 as an elution buffer, hypoviral dsRNA was additionally purified from nucleic acid species present in preparations partially purified by standard CF-11 cellulose chromatography. Moreover, crude phenol/chloroform extracts of the fungal tissue were also applied to monolithic supports and CIM DEAE chromatograms revealed clear evidence for hypoviral presence without CF-11 chromatography, nucleic acid precipitation, and electrophoresis.     

1,3‐Benzothia­zole‐6‐carboxamidinium chloride dihydrate

The title compound, C₈H₈N₃S⁺·Cl⁻·2H₂O, has been synthesized and characterized both spectroscopically and structurally. The structure consists of 1,3‐benzothia­zole‐6‐carboxamidinium cations, chloride anions and water mol­ecules, all interconnected by hydrogen bonds into a three‐dimensional network. The 1,3‐benzo­thia­zole moiety is inclined to the 6‐­amidine group by 36.71 (9)°.     

A new class of nonexpansive type mappings and fixed points

In this paper a new class of self-mappings on metric spaces, which satisfy the nonexpensive type condition (3) below is introduced and investigated. The main result is that such mappings have a unique fixed point. Also, a remetrization theorem, which is converse to Banach contraction principle is given.27. march 80     

Design,Synthesis, and Biological Evaluation of Desmuramyl Dipeptides Modified by Adamantyl-1,2,3-triazole

Muramyl dipeptide (MDP) is the smallest peptidoglycan fragment able to trigger the immune response. Structural modification of MDP can lead to the preparation of analogs with improved immunostimulant properties, including desmuramyl peptides (DMPs). The aim of this work was to prepare the desmuramyl peptide (L-Ala-D-Glu)-containing adamantyl-triazole moiety and its mannosylated derivative in order to study their immunomodulatory activities in vivo. The adjuvant activity of the prepared compounds was evaluated in a murine model using ovalbumin as an antigen, and compared to the reference adjuvant ManAdDMP. The results showed that the introduction of the lipophilic adamantyl-triazole moiety at the C-terminus of L-Ala-D-Glu contributes to the immunostimulant activity of DMP, and that mannosylation of DMP modified with adamantyl-triazole causes the amplification of its immunostimulant activity.