Fabrication of long-term hydrophilic surfaces of poly(dimethyl siloxane) using 2-hydroxy ethyl methacrylate

In the present work, 2-hydroxy ethyl methacrylate (HEMA) was used to modify surface of poly(dimethyl siloxane) (PDMS) elastomer. Fourier transform infrared spectroscopy (FTIR) and wetting angle measurements were used for the analysis of modified surface and hydrophilic stability of PDMS. Results of the surface reconstruction reveal that long-term hydrophilic surfaces of PDMS can be achieved by use of HEMA.     

Intracranial functional MR angiography in humans

Functional MR angiography (fMRA) images have been generated from the brain of healthy volunteers, in response to a hand motor task. Two sets of 3D phase-contrast MR images were, therefore, acquired, one during a resting and one during a task activation period. The MR images measured during rest were subtracted from those measured during task performance. The fMRA images were eventually obtained by calculating maximum intensity projections from the set of subtraction images. The results confirm earlier observations that there is a significant functional response from pial veins to motor activity.     

One-step electrosynthesis of tetrahydrofuran and tetrahydropyran derivatives

The one-step electrosynthesis of tetrahydrofuran and tetrahydropyran derivatives was achieved by electrogenerating in N,N-dimethylformamide and at a mercury pool cathode, radical-anions of benzophenone or fluorenone in the presence of an equivalent of 1,3-dibromopropane 1 or 1,4-dibromobutane 2. In all electrolyses, a competition between ring alkylations and O- and C-alkylations of the keto group is observed. In the case of fluorenone, the spiroethers were isolated as the main compounds. Their yields after purification were respectively 41 and 50% in the presence of 1 and 2. For benzophenone, the yields of the cyclic ethers were low, due mainly to the competitive formation of bridged compounds; the yields of tetrahydrofuran and tetrahydropyran derivatives were respectively 10 and 23%.     

Adolescent idiopathic scoliosis: an update

Adolescent idiopathic scoliosis is defined as a lateral spinal curvature of greater than 10 degrees, for which no pathologic cause can be determined. The initial assessment of adolescents with scoliosis focuses on identification of any treatable underlying pathology. Adolescents with scoliosis typically are asymptomatic and have normal neurologic and physical examinations, with the exception of curvature of the spine. Treatment strategies are determined by the risk of progression. This risk depends on the extent of the curvature and anticipated future spinal growth. The extent of the curvature may be estimated by use of a scoliometer and verified by calculation of the Cobb angle on radiographic evaluation. Skeletal maturity may be estimated by several methods, including radiologic estimates of ossification by bone atlas or Risser sign. Treatment strategies include bracing and surgery.     

On morphology and the competition between crystallization and phase separation in polypropylene–polyethylene blends

Blends of polypropylene (PP) and low density polyethylene (LDPE) have been examined for a series of compositions using differential scanning calorimetry and permanganic etching followed by transmission electron microscopy. Thermal analysis of their melting and recrystallization behaviour suggests two possibilities, either that below 15 wt% PP the blends are fully miscible and that PP only crystallizes after LDPE because of compositional changes in the remaining melt, or else that the PP is separated, but in the form of droplets too small to crystallize at normal temperatures. Microscopic examination of the morphology shows that the latter is the case, but that a fraction of the PP is nevertheless dissolved in the LDPE. © 1998 Kluwer Academic Publishers     

Applications of kriging to image sequence coding

Kriging is a linear interpolation method used by geostatisticians. In this paper we show that it can be successfully applied to image sequence coding. First we apply it to texture coding and we improve these preliminary results with an optimization method that we have named ‘inverse kriging’. Then we apply kriging and inverse kriging to motion vector fields, which are by essence smooth within an object. We show an application of these tools in the framework of the active mesh coding scheme developed within the RACE/Morpheco project.     

DNA sequence analysis of a 17 kb fragment of yeast chromosome XI physically localizes the MRB1 gene and reveals eight new open reading frames,including a homologue of the KIN1/KIN2 and SNF1 protein kinases

We report in this paper the sequence of a part of chromosome XI of Saccharomyces cerevisiae. This 17 kbp nucleotide sequence represents the right half of cosmid pUKG151 and contains nine open reading frames, YKL453, 450, 449, 448, 445, 443, 442, 441 and the 5′ part of YKL440. YKL440 was previously identified as the MBR1 gene and plays a role in mitochondrial biogenesis. YKL443 is a homologue of the yeast serine-rich protein (SRP1), while YKL453 presents strong homologies with the KIN1/KIN2/SNF1 kinase family. It must be pointed out that the size of this gene is well above average for yeast.     

Contact Sex Signals in Two Sympatric Spider Species, Tegenaria domestica and Tegenaria pagana

Bioassays in two sympatric spider species, Tegenaria domestica and T. pagana, demonstrate that the total female chemical extract, and in particular the polar fraction, are involved in the sexual behavior of males and reproductive isolation mechanisms. In T. domestica female attractiveness was correlated with changes in 18 chemical compounds. In T. pagana little difference was observed between 12 compounds in extracts of attractive and unattractive females. 12- + 10-Methyloctacosane was not detected in attractive females of either species. Reproductive isolation was linked not only to quantitative changes in 18 chemical compounds detected in both species, but also to nine compounds present in one or the other species.     

Search for unstable DNA in schizophrenia families with evidence for genetic anticipation

Evidence for genetic anticipation has recently become an important subject of research in clinical psychiatric genetics. Renewed interest in anticipation was evoked by molecular genetic findings of a novel type of mutation termed "unstable DNA." The unstable DNA model can be construed as the "best fit" for schizophrenia twin and family epidemiological data. We have performed a large-scale Southern blot hybridization, asymmetrical PCR-based, and repeat expansion-detection screening for (CAG)n/(CTG)n and (CCG)n/(CGG)n expansions in eastern Canadian schizophrenia multiplex families demonstrating genetic anticipation. There were no differences in (CAG)n/(CTG)n and (CCG)n/(CGG)n pattern distribution either between affected and unaffected individuals or across generations. Our findings do not support the hypothesis that large (CAG)n/(CTG)n or (CCG)n/(CGG)n expansions are the major etiologic factor in schizophrenia. A separate set of experiments directed to the analysis of small (30-130 trinucleotides), Huntington disease-type expansions in individual genes is required in order to fully exclude the presence of (CAG)n/(CTG)n- or (CCG)n/(CGG)n-type unstable mutation.