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Bitumen with 50/70 penetration was prepared and modified by doping with the unsaturated polyester resin based on isophthalic acid at 5% by weight (w/w%).The structural, mechanical, and thermal properties of bitumen and bitumen modified with unsaturated polyester resin %5 (UPR) were determined. The dielectric properties of bitumen and modified bitumen were investigated in the frequency and temperature ranges of 0.1-106Hz and (-)40°C- 40°C, respectively. Polarization mechanisms, glass-transition temperature, and ductility of all samples were determined and compared to each other. The glass transition temperature of the modified bitumen shifts toward low temperatures in comparison to the bitumen. So, it can be suggested that the use of modified bitumen is very attractive in regions where the temperature differences are high. Also, the dielectric analysis method is an innovative alternative to determining modified bitumen's low-temperature performance. It was found that the modification with UPR provide strength and flexibility to asphalt.

Dielectric properties of bitumen with different thicknesses were investigated by dielectric spectroscopy in the frequency range from 0.1 Hz to 1 MHz and temperature range from (−)40°C to 40°C. The polarisation regions were determined for all samples by using the Cole–Cole equation. While one polarisation region was observed in dielectric constant and dielectric loss factor (tanδ), three polarisation regions were observed in ac conductivity (). These polarisation mechanisms were identified. The effects of thickness on dielectric properties and glass transition temperature (Tg) of bitumen were studied. Toward higher thicknesses (up to 4 mm) the dielectric constant () increased with increasing thickness. After 5 mm, the dielectric constant became independent of thickness that it had a constant value of about 5.5. Tgwas affected by sample thickness and it was observed that glass transition temperature varies in the temperature range from (−)50°C to 5°C. and Tgis thickness dependent until the thickness of 5 mm. It was found that Tgobtained from dielectric properties for the bulk phase is compatible with Tgobtained in structural analysis. So, it can be suggested that dielectric spectroscopy may be an alternative analyzing technic for investigation of rheologic properties of bitumen.

Pure GaAs and GaAs1−xBixalloys with different Bi ratios (1 %, 2.5 %, 3.5 %) fitted with silver contacts were measured with a dielectric spectroscopy device. Dielectric characterization was performed at room temperature in the frequency range of 0.1 Hz to 1 MHz. GaAs exhibits three relaxation regions corresponding to space-charge, dipolar and ionic polarizations in sequence with increasing frequency while GaAs1−xBixsamples show only a broad dipolar polarization in the same frequency range. This result proves the filling of the lattice with Bi through making a new bonding reducing the influence of ionic polarization. This finding supports the previous results concerning optical properties of GaAs1−xBix, presented in the literature.

Mosaic Intrachromosomal Triplication of (12)(p11.2p13) in a Patient with Pallister-Killian SyndromePallister-Killian syndrome (PKS) is a rare genetic disorder usually characterized by mosaic tetrasomy of isochromosome 12p detected in cultured fibroblast cells. We describe here a patient with PKS and intrachromosomal triplication of the short arm of chromosome 12. Her karyo-type was mos 46, XX, inv trp(12)(p11.2p13)[34]/46, XX[16] de novoby conventional cytogenetics and fluorescent in situhybridization (FISH) analysis. However, this chromosomal abnormality was not detected from the patient's cultured blood lymphocytes. We report here the third patient with intrachromosomal triplication on the short arm of chromosome 12, presenting a PKS phenotype.

Turner Syndrome with Isochromosome Xq and Familial Reciprocal Translocation t(4;16)(p15.2;p13.1)We present here a 16-year-old Turner syndrome patient with a complex karyotype that includes a maternally-inherited balanced translocation between chromosomes 4 and 16 and mosaicism of the isochromosome Xq10. Her karyotype was 45, X, t(4;16) (p15.2;p13.1)[9]/46, X, i(X) (q10),t(4;16)(p15.2;p13.1) [91]. The karyotype of her father was normal, whereas that of her mother had the same balanced translocation and numerical abnormalities of chromosome X and was designated as 45, X, t(4;16)(p15.2;p13.1) [2]/ 46, XX, t(4;16)(p15.2;p13.1)[93]/47, XXX, t(4;16) (p15.2; p13.1)[5]. The two siblings of the patient also had the same reciprocal translocation. We consider this to be the first such patient with an inherited reciprocal translocation and structural abnormality of the X chromosome (isochromosome Xq).

Aplasia Ras Homologous Member I Gene and Development of Glial TumorsThe ARHI (aplasia Ras homologue member I, also known as DIRAS3) gene shows 60.0% sequence homology to the Ras proto-oncogene and was the first mater-nally-imprinted tumor suppressor gene identified in the Ras family. It is constitutively expressed from the paternal allele in normal breast, ovary, heart, liver, pancreas, thyroid and brain tissues, and is lost or markedly down-regulated primarily in breast, ovarian, pancreas and thyroid tumor tissues. We have investigated the expression, LOH (loss of heterozygosity) and methylation status of this gene in glial tumors and peripheral blood samples of 21 patients, and in seven normal brain tissue samples. Gene expression by real time reverse transcriptase polymerase chain reaction (RTPCR) was found to be increased in 14 and decreased in seven of the 21 tumors. The LOH was detected by fragment analysis, using five labeled polymorphic markers specific for the 1p31 region, in two of the tumors. Methylation status of the CpG island I, II and III was evaluated using COBRA (combined bisulfite restriction analysis) and RFLP (restriction fragment length polymorphism) in 21 tumors and also a hypermethylated healthy volunteer as a positive control, revealed that only two tumors had hypermethylation in CpG island I (of which one also had LOH). These results suggest that LOH and hypermethylation may be one mechanism of silencing the ARHI gene expression and development of glial tumor development.

Dielectric properties of Sb2Te3 films prepared by thermal evaporation technique onto clean glass substrates using ohmic aluminum electrodes have been investigated in the frequency range of 0.01- 100 kHz and within the temperature range of 293K- 373 K. Both the dielectric constant e1 and dielectric loss factor were found to depend on frequency and temperature. The activation values were evaluated and good agreement between the activation energy values obtained from capacitance and dielectric loss factor measurements were obtained.