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Glioma stem cells: Evidence and limitation.

Gliomas, in particular the high-grade anaplastic glioma and glioblastoma multiforme (GBM), are manifested by morphological, genetic and phenotypic heterogeneity. Most of the studies hitherto have been performed on bulk glioma cells, with limited understanding on the origin and the relative contribution of particular glioma cell populations to glioma growth and progression. Recent studies have demo

Correlation potential in density functional theory at the GWA level: Spherical atoms

As part of a project to obtain better optical response functions for nanomaterials and other systems with strong excitonic effects, we here calculate the exchange-correlation (XC) potential of density functional theory (DFT) at a level of approximation which corresponds to the dynamically screened exchange or GW approximation. In this process, we have designed a numerical method based on cubic spl

Abberant cytogenetic evolution pattern of Philadelphia-positive chronic myeloid leukemia treated with interferon-alpha

The cytogenetic evolution of 32 Philadelphia (Ph)-positive chronic myeloid leukemias (CML) receiving interferon-alpha (IFN-alpha) therapy was compared to the patterns in untreated CML and cases treated with busulfan (Bu), hydroxyurea (Hy), and allogeneic bone marrow transplantation (BMT). Half of the CML receiving IFN-alpha had at least one of the well-known major or minor route aberrations wherea

Lunar orientation in a beetle

Many animals use the sun's polarization pattern to orientate, but the dung beetle Scarabaeus zambesianus is the only animal so far known to orientate using the million times dimmer polarization pattern of the moonlit sky. We demonstrate the relative roles of the moon and the nocturnal polarized-light pattern for orientation. We find that artificially changing the position of the moon, or hiding th

Determination of banned azo dyes in consumer goods

Azo dyes, extensively used for coloring a variety of consumer goods, such as leather, clothes, food, and toys, can under certain conditions be reduced to form confirmed or suspected carcinogenic aromatic amines. This article gives an overview of the state of development of analytical procedures for the determination of such azo dyes, which are banned by the European Commission. (C) 2004 Elsevier L

Conserved methionines in chloroplasts

Heat shock proteins counteract heat and oxidative stress. In chloroplasts, a small heat shock protein (Hsp21) contains a set of conserved methionines, which date back to early in the emergence of terrestrial plants. Methionines M49, M52, M55, M59, M62, M67 are located on one side of an amphipathic helix, which may fold back over two other conserved methionines (M97 and M101), to form a binding gro

When crowded tadpoles (Rana arvalis and R-temporaria) fail to metamorphose and thus fail to escape drying ponds

Do moor frog (Rana arvalis) and common frog (R. temporaria) tadpoles increase developmental rate if there is a risk of their pond drying up before metamorphosis? To study this, I performed an experiment designed to mimic natural conditions in many drying ponds. The number of tadpoles per tank was constant during the experiment but the water level was lowered in experimental tanks so that crowding

Flamelet modelling of soot formation in diffusion flames

In this work the steady and unsteady flamelet models have been applied to soot formation in laminar and turbulent diffusion flames. The aim was to study how different model parameters affect soot formation in diffusion flames. It was shown that certain assumptions are more crucial in laminar diffusion flames than in turbulent ones. The soot formation in turbulent diffusion flames is more sensitive

Contextual perspectives on education in materials science and engineering

From an inside point of view, the concept of a "unified science of materials" might appear to be quite natural in its own right, as it were. However, considering the fact that science in general is practiced by humans in a social environment, it should be warranted to examine materials science also from the humanistic and sociological perspectives, as well as against the background of current thin

Common structure in amorphised compound semiconductors

Extended X-ray absorption fine structure has been utilised to determine the structural parameters of the amorphous III-V semiconductors GaP, GaAs, InP and InAs. The amorphous phase was formed by ion implantation to inhibit preparation-specific artefacts associated with the alternative fabrication techniques of sputtering and evaporation. Relative to crystalline standards, increases in bond length