Structural and Electrical Characterization of Undoped Diamond Layer Grown by HF CVD

The undoped diamond layers were prepared using hot filament chemical vapor deposition technique. The controlled variation of the deposition parameters resulted in the layers with varying amount of nondiamond impurities. Routine characterization of the layers was carried out using scanning electron microscopy, X-ray diffractometry, and the Raman spectroscopy. Detailed measurements of room temperature electrical conductivity (σ₃₀₀), current-voltage characteristics have yielded useful information about the electrical conduction mechanism in this interesting material. The σ₃₀₀ and I-V characteristic measurements were done in sandwiched configuration taking care off the surface effects. The diamond shows room temperature dc conductivity reaching the values in the range of σ₃₀₀ ≈0.1-1 μS/cm. The I-V characteristics in these layers show space charge limited conduction behavior with I ~ V² in high voltage region. The obtained results are explained in terms of chemically adsorbed hydrogen on the surface of diamond layers, which is a source of acceptor states just above the top of valence band

Associations between vaspin rs2236242 gene polymorphism, walking time and the risk of metabolic syndrome

The associations between serum vaspin levels and metabolic or coronary artery disease (CAD) and polycystic ovary syndrome (PCOS) is under the scope of current researchers. Therefore, this adipokine can be considered as a biomarker of metabolic syndrome (MetS). The aim of the study was to analyze the associations between the vaspin rs2236242 polymorphism and physical activity in relation to MetS and its components. The analysis involved the genetic material and clinical data of 108 individuals with MetS and 110 controls. Vaspin rs2236242 polymorphism was detected using the tetra-primer amplification-refractory mutation system polymerase chain reaction (T-ARMS PCR) method. The TA genotype of vaspin rs2236242 was associated with a greater risk of MetS and its components compared with the TT genotype. The analysis of interactions between genotype and walking time revealed that a walking time longer than 60 min./day significantly decreased the risk of MetS in the TA carriers (p = 0.007). The obtained results suggest that any unfavorable effect of the TA genotype of the vaspin rs2236242 polymorphism can be essentially reduced, or even reversed, in a case of individuals walking longer than 60 min. a day. The analysis of the interaction between vaspin rs2236242 polymorphism and walking showed that a walking time of longer than 1 hour a day significantly reduced the risk of MetS, elevated blood pressure and triglycerides concentration