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Identifying changes in DNA copy number can pinpoint genes that may be involved in tumor development. Here we have defined the smallest overlapping regions of imbalance (SORI) in testicular germ cell tumors other than the 12p region, which has been previously investigated. Definition of the regions was achieved through comparative genomic hybridization (CGH) analysis of a 4559 cDNA clone microarray. A total of 14 SORI were identified, which involved at least five of the 11 samples analysed. Many of these refined regions were previously reported using chromosomal or allelic imbalance studies. The SORI included gain of material from the regions 4q12, 17q21.3, 22q11.23 and Xq22, and loss from 5q33, 11q12.1, 16q22.3 and 22q11. Comparison with parallel chromosomal CGH data supported involvement of most regions. The various SORI span between one and 20 genes and highlight potential oncogenes/tumor suppressor genes to be investigated further (Supplementary material is available at http://www.crukdmf.icr.ac.uk/array/array.html ).

Glassy carbon is a continuous, isotropic and non-graphitizing carbon that combines the properties of glass and ceramic with those of graphite. It has excellent properties such as high tensile strength, high hardness, good thermal and electrical conductivity, and combined resistance to high temperatures, wear, and corrosion. Glassy carbon is also highly impermeable to gases and liquids. These outstanding properties of glassy carbon make it a good choice for nuclear applications.Glassy carbon has been proposed as a containment material for radioactive fission products. For glassy carbon to be considered a suitable candidate for fission products containment, it must be an effective diffusion barrier for fission products, such as ruthenium (Ru), and its microstructure should not change dramatically under ion bombardment and extreme heat conditions.In this study, 150 keV Ru ions were implanted into glassy carbon at room temperature and 200 ˚C to a fluence of 1×1016cm-2. The as-implanted samples were annealed at two temperature regimes (from 500 to 1000 °C and from 1000 to 1300 °C – in steps of 100 °C) for 5 h under vacuum. This study investigates the structural modifications and surface characteristics of glassy carbon under the influence of Ru ion implantation and subsequent heat treatment. Ru migration in glassy carbon was also investigated. Moreover, several techniques, including Raman spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM), and scanning electron microscopy (SEM), have been used to examine the microstructure and surface topography of glassy carbon before and after ion implantation and heat treatment. Moreover, secondary ion mass spectrometry (SIMS) and Rutherford backscattering spectrometry (RBS) were used to study Ru migration in glassy carbon.Raman spectroscopy was utilized to monitor the structural variations in glassy carbon resulting from Ru implantation and heat treatment. The study involved analyzing the Raman spectra through baseline correction, fitting with Gaussian and Breit-Wigner-Fano functions, and deriving key parameters such as peak intensity, FWHM (full width at half maximum), and peak position. Variations in these parameters were used to assess glassy carbon structures, especially defects, crystal size, and residual stress. The study identified that the D and G bands in the Raman spectrum, associated with disordered sp3 bonds and sp2 vibrations of graphite, provided insights into the presence of graphitic crystallites in glassy carbon. Furthermore, it was observed that Ru implantation led to the merging of D and G peaks into a single broadband. This indicates the amorphization of graphitic crystallites in glassy carbon. However, a broader G peak was present in the Raman spectrum of the as-implanted samples at room temperature compared to those implanted at 200 °C which indicated that the magnitude of radiation damage in the room temperature implanted sample is more than in the 200 °C implanted sample.Annealing at 500 °C resulted in initiated partial recrystallization, while higher annealing temperatures of 600 to 1300 °C led to enhanced recovery of the glassy carbon structure. However, even after annealing at 1300 °C, the glassy carbon structure did not fully return to its virgin state, indicating the persistence of some damage introduced by Ru ion implantation.The positions of the G peaks were found to shift after implantation, and the nature of this shift was attributed to stress. Tensile stress was associated with shifts to lower wavenumbers, while shifts to higher wavenumbers indicated compressive stress. The study showed that Ru implantation induced tensile stress in glassy carbon, while annealing reduced tensile stress. However, at temperatures above 900 °C, compressive stress was introduced, consistent with findings from previous studies which correlated residual stress to glassy carbon density. As confirmed by Raman measurements, XRD analysis of glassy carbon samples revealed an increase in tensile strain following Ru implantation, while annealing at temperatures over 900 °C resulted in an increase in compressive strain.RBS and SIMS were used to monitor the migration behaviour of Ru in glassy carbon after annealing at both low and high temperatures. Annealing the as-implanted samples at temperatures ranging from 500 to 1300 °C had distinct effects on the Ru depth profiles. Annealing from 500 to 800 °C showed no significant change in the Ru depth profiles, indicating the non-diffusivity of Ru in glassy carbon at these lower temperatures. However, annealing at temperatures above 900 °C led to noticeable changes in the depth profiles. These changes included an increase in the maximum depth profile peak, a shift towards the surface, and a decrease in the FWHM. These changes suggested Ru aggregation at these higher temperatures, forming nanoparticles within the glassy carbon. In addition, more Ru aggregation was observed in room temperature implanted samples compared to those implanted at 200 °C. This discrepancy could be attributed to the higher concentration of defects in room temperature implanted samples, which may promote Ru aggregation and cluster formation. It aligns with the idea that impurity clusters are more likely to form in regions with high defect concentrations. The aggregation of Ru was accompanied by a shift of depth profiles towards the glassy carbon surface. This shift was attributed to a stress field that resulted in the migration of the profiles as a whole. The Raman and XRD results indicated the introduction of high levels of stress in the implanted region due to Ru implantation and annealing, which contributed to the observed depth profile shift. Moreover, the Ru peak shift toward the surface was lower in the room temperature implanted samples than in the 200 °C implanted samples. This was due to increased Ru aggregation within the room temperature implanted samples. This caused Ru clusters to grow larger, causing Ru to migrate more slowly toward the surface compared to the 200 °C implanted samples which showed less Ru aggregation. In addition to that, the high concentration of defects in the room temperature implanted sample played a role in trapping the majority of the Ru atoms in the high radiation damage region which restricted its migration towards the surface. Importantly, annealing at both low and high temperatures did not result in a noticeable loss of the Ru implanted in glassy carbon. This was likely due to Ru aggregation forming clusters inside the glassy carbon, preventing Ru out-surface diffusion. In light of this, the glassy carbon material may serve as an effective container for Ru fission product.The study conducted SEM and AFM analyses to assess surface changes in glassy carbon substrates following Ru implantation and heat treatment. After Ru implantation, surface roughness decreased substantially, with the Rq (root mean square roughness) values dropping from 1.45±0.05 nm for virgin glassy carbon to 0.40±0.05 nm for room temperature implanted samples and 0.37±0.05 nm for 200 °C implanted samples. This decrease was attributed to Ru bombardment. However, annealing at 1000 °C led to a significant increase in Rq values, reaching 1.10±0.12 nm for 200 °C implanted samples and 1.15±0.12 nm for room temperature implanted samples. This increase was primarily due to the aggregation of Ru atoms, possibly forming Ru nanoparticles near the surface. Subsequent annealing at temperatures between 1100 °C and 1200 °C reduced Rq surface roughness for room temperature implanted samples. This decrease was attributed to the surface diffusion of substrate atoms, causing them to shift from the peaks to valley positions on the sputter-roughened surface. Consequently, the initial polishing marks became less pronounced. No change in Rq surface roughness was observed for 200 °C implanted samples after annealing at 1100 °C and 1200 °C, potentially due to a shift in the depth profile toward the surface. Annealing at 1300 °C resulted in an increase in Rq surface roughness, with values reaching 2.25±0.27 nm for room temperature implanted samples and 2.75±0.27 nm for 200 °C implanted samples. This increase was linked to the formation of large carbon island clusters on the surface.In summary, Ru implantation and heat treatment significantly influenced glassy carbon substrate Rq surface roughness. The observed variation in response to annealing at higher temperatures could be attributed to Ru migration, cluster formation, and substrate atom diffusion.

Introduction: It is known for many years, that grand multiparity is associated with poor pregnancy outcome with or without considering increasing maternal age. Aim: To examine the impact of grand multiparity on pregnancy outcome in young women aged 18–34 years (Young grand multiparas). Material and Methods: A prospective comparative cross-sectional study conducted at Omdurman Maternity Hospital, Sudan from January to September 2018. A standard questionnaire was used to gather data on pregnancy outcome in the low-risk group, grand multiparas age < 35 years and grand multiparas age ≥ 35 years. The association between variables was tested with Chi-square test. Results: Young grand multiparas have a significant risk of PPH and increased length of hospital stay => 3 days and babies born to young grand multiparas women were more likely of low birth weight and have a higher rate of admission to NICU. Young grand multiparas were similar in their maternal and fetal complication to low-risk pregnancies and significantly less in several complications when compared to older grand multiparas women. Conclusion: Young grand multiparas are less likely to develop several pregnancy complications compared to older grand multiparas women. The occurrences of intra-partum complications match that in low-risk pregnancy.