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Abstract In this report we demonstrate the results of charge carriers transport studies in graphene using a Hall effect sensor fabricated on quasi-free-standing monolayer graphene grown on a semi-insulating on-axis vanadium-compensated 6H-SiC(0001) substrate in an epitaxial Chemical Vapor Deposition process. The sensor is passivated with aluminum oxide through atomic layer deposition and offers current-mode sensitivity of 140 V/AT with thermal stability of − 0.02%/K within the range between 80 and 573 K. The electrical properties of the graphene layer are determined as a function of temperature ranging from 300 to 770 K. High-temperature characteristics of passivated and not passivated graphene are compared and their profiles explained through a double-carrier transport involving the spontaneous-polarization-induced holes in the graphene layer and the thermally activated electrons from a shallow donor level of nitrogen in the quasi-cubic (k 1) site and a deep acceptor level of vanadium in the hexagonal (h) site both present in the bulk of the vanadium-compensated SiC substrate. Finally, we conclude that this mechanism is directly responsible for the limitation of the thermal stability of the sensor's current-mode sensitivity. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Family delivery is an important aspect of modern obstetrics. The aim of this study was to estimate the phenomenon of family delivery from the standpoint of participating and non-participating fathers. Study design: Two types of questionnaires were used in the study. Five hundred and five men were divided into two groups: (A) delivery participants and (B) delivery non-participants. Results: The participants were significantly younger than non-participants. Better educated men dominated in group (A), whereas men with trade education were the majority in group (B). Low birth classes attendance among women in group (B) was noticed. All men in group (B) knew about the possibility of taking part in the delivery. Almost 100% of participants declared their satisfaction with family delivery. For non-participants, wife and media were the main source of knowledge, while for participants it was the medical staff and labor schools. Conclusions: Family labor is commonly accepted by both partners and is generally connected with positive emotions. This phenomenon is generally approved by couples with higher economical status. Family labor resignation, common among pairs with lower economical status, is caused generally by fear and lack of proper knowledge. Health care providers, through labor schools and outpatients visits, should concentrate on getting to couples, whose attitude towards family labor is negative. Educational programs and popular press articles should be prepared more thoroughly, focusing on the whole population of potential fathers. [Copyright &y& Elsevier]

We previously demonstrated that low K intake stimulated the expression of c-Src and that stimulation of protein tyrosine kinase inhibited ROMK channel activity (Wei, Y., Bloom, P., Lin, D. H., Gu, R. M., and Wang, W. H. (2001) Am. J. PhysioL 281, F206–F212). Decreases in dietary K content significantly increased 0 levels and the phosphorylation of c-Jun, a transcription factor, in renal cortex and outer medulla. The role of O¯2 and related products such as H2O2 in stimulating the expression of protein tyrosine kinase is suggested by the observation that addition of 50–200 μM H2O2 increased the phosphorylation of c-Jun and the expression of c-Src in Ml cells, a mouse collecting duct principal cell line. The effect of H2O2 on c-Src expression was completely abolished with cyclohexamide or actinomycin D. The treatment of animals on a K-deficient (KD) diet with tempol for 7 days significantly decreased the production of O¯2; c-Jun phosphorylation, and c-Src expression. Moreover, low K intake decreased the activity of ROMK-like small conductance channels from 1.37 (control K diet) to 0.5 in the cortical collecting duct and increased the tyrosine phosphorylation of ROMK in the renal cortex and outer medulla. In contrast, the tempol treatment not only increased channel activity to 1.1 in the cortical collecting duct but also decreased the tyrosine phosphorylation of ROMK from rats on a KD diet. Finally, suppressing O¯2 production with tempol significantly increased renal K excretion measured with metabolic cage and lowered the plasma K concentration in comparison with those on a KD diet alone without tempol. We conclude that O and related products play a role in mediating the effect of low K intake on c-Src expression and in suppressing ROMK channel activity and renal K secretion. [ABSTRACT FROM AUTHOR]