On the Orthogonal Tableaux of Koike and Terada

Many different definitions have been given for semistandard odd and even orthogonal tableaux which enumerate the corresponding irreducible orthogonal characters. Weightpreserving bijections have been provided between some of these sets of tableaux (see [3], [8]). We give bijections between the (semistandard) odd orthogonal Koike-Terada tableaux and the odd orthogonal Sundaram-tableaux and between the even orthogonal Koike-Terada tableaux and the even orthogonal King-Welsh tableaux. As well, we define an even version of orthogonal Sundaram tableaux which enumerate the irreducible characters of O(2n).     

Electrostatically Self-Assembled Multilayers of Chitosan and Xanthan Studied by Atomic Force Microscopy and Micro-Interferometry

The thickness and surface morphology of electrostatically self-assembled films of chitosan and xanthan (persistence length of ∼120nm) have been studied using dual-wavelength Reflection Interference Contrast Microscopy (DW-RICM) and tapping mode Atomic Force Microscopy (AFM). The multilayers were prepared at two ionic strengths (5mM and 150mM). When the multilayers were assembled at 150 mM a network like morphology was observed after one bilayer. This structure was found to be of large influence in the further growth of the multilayers, with the same kind of network structure being observed at all number of bilayers. A lack of swelling behaviour, as well as the network structure and the poresize of the network, is suggested to originate from the high chain stiffness of xanthan.     

Transfer of protoporphyrin IX between cells

Human adenocarcinoma cells of the line WiDr and human leukemia T cells of the line Jurkat were incubated with 5-aminolevulinic acid and found to produce protoporphyrin IX (PpIX). They were able to transfer a fraction of the sensitizer to neighboring control cells. The transfer took place through direct membrane contact. Light exposures, inactivating about 20% of the sensitized cells, did not result in any acceleration of the transfer of PpIX. This is in contrast to what has been reported for PpIX in erythrocytes from patients with erythropoietic protoporphyria. In these cells light exposure transfers PpIX from the binding sites on hemoglobin to the plasma membrane and further to neighboring cells. The lack of light-induced transfer in the WiDr and Jurkat cells may be related to the binding sites of PpIX, supposedly membrane lipids and proteins embedded therein. Light exposure slightly increased the rate of loss of PpIX from WiDr cells.     

Extension of Fourier algebra homomorphisms to duals of algebras of uniformly continuous functionals

For a locally compact group G, let XG be one of the following introverted subspaces of VN(G): , the C^∗-algebra of uniformly continuous functionals on A(G); , the space of weakly almost periodic functionals on A(G); or , the C^∗-algebra generated by the left regular representation on the measure algebra of G. We discuss the extension of homomorphisms of (reduced) Fourier-Stieltjes algebras on G and H to cb-norm preserving, weak^∗-weak^∗-continuous homomorphisms of into , where (XG,XH) is one of the pairs , , or . When G is amenable, these extensions are characterized in terms of piecewise affine maps.     

Small angle x-ray scattering study of local structure and collapse transition of (1,3)-beta-D-glucan-chitosan gels

Scleroglucan is a (1,3)-beta-D-glucan polysaccharide produced by the fungus Sclerotium. Dissolved in water at room temperature it adopts a linear, rigid, triple helical structure. Gelation of scleroglucan can be obtained by Schiff-base formation between partly periodate oxidized scleroglucan and the primary amine groups of chitosan. The scleraldehyde-chitosan gels exhibit a collapse transition when exposed to volume fractions of isopropanol, Wp, larger than 65%. The aim of the present study is to provide structural information concerning the local polymer distribution and the collapse transition in (1,3)-beta-D-glucan-chitosan gels. Small angle x-ray scattering was used to investigate solutions and gels of scleroglucan in water, as well as in an aqueous mixture containing 65% isopropanol. The results reveal that in aqueous solution, the polysaccharide scleroglucan chains have an approximately cylindrical cross section of external diameter close to 17 A. The gels display the same local structure, but form clusters on a longer distance scale. For the collapsed gels in the water-isopropanol mixture, partial phase separation occurs in which ordered domains of approximate size of 110 A develop. This study indicates that local ordering in liquid-crystalline-type domains is a possible molecular mechanism contributing to the collapse of gels composed of semiflexible polymers. The triple helical structure of the molecule appears not to be conserved in the majority phase in this solvent, but it is conserved in the liquid crystalline domains.     

SITES OF PHOTODYNAMICALLY INDUCED DNA REPAIR IN HUMAN CELLS

Abstract Human REH cells were incubated with the photosensitizers meso -tetra(4-sulfonatophenyl)porphyrin (TSPP=TPPS₄) or meso -tetra(3-hydroxyphenyl)porphyrin (3-THPP). The relatively hydrophilic TSPP was partly found in the cytoplasm and partly in the nuclei, whereas the lipophilic 3-THPP was found apparently in membranes and not inside the nuclei. After illumination, sites of DNA repair were labeled by means of a monoclonal antibody against proliferating cell nuclear antigen (PCNA) bound in the nuclei. The amount of bound PCNA in non-S-phase cells was proportional to the light dose. The bound PCNA was homogeneously distributed in the nuclei 0.5 h after photodynamic treatment (PDT) with TSPP. In contrast, for cells given PDT with 3-THPP, the periphery of the nuclei was selectively labeled, indicating that the initial DNA damage was localized close to the sensitizer at the nuclear membrane.     

Chromatographic profile of high boiling point organic acids in human urine

The profile of high boiling point organic acids in urine samples from both normal subjects and patients suspected of having some form of metabolic disorder has been determined by combined gas chromatography-mass spectrometry. Fifteen different compounds eluting after hippuric acid have been identified, including two, cinnamoylglycine and acetyltributylcitrate, which have not been recognised previously. Relative retention times and abbreviated mass spectra of the identified compounds are presented.     

Amenability of Banach and C-algebras generated by unitary representations

We study the amenability of a locally compact group in relation to the amenability properties of a variety of -algebras and (quantized/dual) Banach algebras naturally associated to a unitary representation of .

     

Solid-phase analytical derivatization of alkylphenols in fish bile for gas chromatography-mass spectrometry analysis

Solid-phase analytical derivatization (SPAD) with bis(trimethylsilyl)trifluoroacetamide (BSTFA) has successfully been used as a sample preparation method for determination of (APs) in fish bile treated with beta-glucuronidase and sulfatase. Derivatized APs were analysed by gas chromatography-mass spectrometry in the electron ionization mode (GC-EI-MS). Overall limits of detection (LODs) ranged from 5 to 18ng/g bile for 19 out of 21 investigated compounds. LODs were not determined for 4-methylphenol and 4-tert-octylphenol due to high background levels in control bile. Recoveries ranged from 83 to 109%. The analysed APs vary in degree of alkylation from methyl (C(1)) to nonyl (C(9)), and represent various pollution sources, including produced water (PW) discharge from the offshore oil industry. The applicability and sensitivity of the method has been demonstrated by analysis of bile taken from Atlantic cod (Gadus morhua L.) exposed to two dilutions of PW (1:500 and 1:1500) in a continuous flow system.