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Nanocrystalline diamond (NCD) field emitters have attracted significant interest for vacuum microelectronics applications. This work presents an approach to enhance the field electron emission (FEE) properties of NCD films by co-doping phosphorus (P) and nitrogen (N) using microwave plasma-enhanced chemical vapor deposition. While the methane (CH4) and P concentrations are kept constant, the N2 concentration is varied from 0.2% to 2% and supplemented by H2. The composition of the gas mixture is tracked in situ by optical emission spectroscopy. Scanning electron microscopy, atomic force microscopy (AFM), transmission electron microscopy, and Raman spectroscopy are used to provide evidence of the changes in crystal morphology, surface roughness, microstructure, and crystalline quality of the different NCD samples. The FEE results display that the 2% N2 concentration sample had the best FEE properties, viz. the lowest turn-on field value of 14.3 V/µm and the highest current value of 2.7 µA at an applied field of 73.0 V/µm. Conductive AFM studies reveal that the 2% N2 concentration NCD sample showed more emission sites, both from the diamond grains and the grain boundaries surrounding them. While phosphorus doping increased the electrical conductivity of the diamond grains, the incorporation of N2 during growth facilitated the formation of nano-graphitic grain boundary phases that provide conducting pathways for the electrons, thereby improving the FEE properties for the 2% N2 concentrated NCD films.The vascular response to hypoxia and ischemia is essential for maintaining homeostasis during stressful conditions and is particularly critical for vital organs such as the heart. Hypoxia-inducible factor-1 (HIF-1) is a central regulator of the response to hypoxia by activating transcription of numerous target genes, including vascular endothelial growth factor (VEGF). Here we identify the guanine nucleotide exchange factor (GEF) Vav1, a regulator of the small Rho-GTPase and cell signaling in endothelial cells, as a key vascular regulator of hypoxia. We show that Vav1 is present in the vascular endothelium and is essential for HIF-1 activation under hypoxia. So, we hypothesized that Vav1 could be a key regulator of HIF-1 signaling. In our findings, Vav1 regulates HIF-1α stabilization through the p38/Siah2/PHD3 pathway. In normoxia, Vav1 binds to vascular endothelial growth factor receptor 1 (VEGFR1), which directs Vav1 to lysosomes for degradation. In contrast, hypoxia upregulates Vav1 protein levels by inhibiting lysosomal degradation, which is analogous to HIF-1α regulation by hypoxia both proteins are constitutively produced and degraded in normoxia allowing for a rapid response when stress occurs. Consequently, hypoxia rapidly stabilizes Vav1, which is required for HIF-1α accumulation. This shows that Vav1 is the key mediator controlling the stabilization of HIF1α in hypoxic conditions. With this finding, we report a novel pathway to stabilize HIF-1, which shows a possible reason why clinical trials targeting HIF-1 has not been effective. Targeting Vav1 can be the new approach to overcome hypoxic tumors.This paper discusses a state-of-the-art inline tubular sensor that can measure the viscosity-density of a passing fluid. In this study, experiments and numerical modelling were performed to develop a deeper understanding of the tubular sensor. Experimental results were compared with an analytical model of the torsional resonator. Good agreement was found at low viscosities, although the numerical model deviated slightly at higher viscosities. The sensor was used to measure viscosities in the range of 0.3-1000 mPa·s at a density of 1000 kg/m3. Above 50 mPa·s, numerical models predicted viscosity within ±5% of actual measurement. However, for lower viscosities, there was a higher deviation between model and experimental results up to a maximum of ±21% deviation at 0.3 mPa·s. The sensor was tested in a flow loop to determine the impact of both laminar and turbulent flow conditions. No significant deviations from the static case were found in either of the flow regimes. The numerical model developed for the tubular torsional sensor was shown to predict the sensor behavior over a wide range, enabling model-based design scaling.(1) Background Compounds with multitarget activity are of interest in basic research to explore molecular foundations of promiscuous binding and in drug discovery as agents eliciting polypharmacological effects. Our study has aimed to systematically identify compounds that form complexes with proteins from distinct classes and compare their bioactive conformations and molecular properties. (2) Methods A large-scale computational investigation was carried out that combined the analysis of complex X-ray structures, ligand binding modes, compound activity data, and various molecular properties. (3) Results A total of 515 ligands with multitarget activity were identified that included 70 organic compounds binding to proteins from different classes. These multiclass ligands (MCLs) were often flexible and surprisingly hydrophilic. Moreover, they displayed a wide spectrum of binding modes. In different target structure environments, binding shapes of MCLs were often similar, but also distinct. (4) Conclusions Combined structural and activity data analysis identified compounds with activity against proteins with distinct structures and functions. MCLs were found to have greatly varying shape similarity when binding to different protein classes. Hence, there were no apparent canonical binding shapes indicating multitarget activity. Rather, conformational versatility characterized MCL binding.The polymerizable reduced graphene oxide (mRGO) grafted styrene-acrylonitrile copolymer composites were prepared via free radical polymerization. The graphene oxide (GO) and reduced graphene oxide (rGO) was reacted with 3-(tri-methoxysilyl)propylmethacrylate (MPS) and used as monomer to graft styrene and acrylonitrile on its surface. The successful modification and reduction of GO was confirmed using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analyzer (TGA), Raman and X-ray diffraction (XRD). The mRGO was prepared using chemical and solvothermal reduction methods. The effect of the reduction method on the composite properties and nanosheet distribution in the polymer matrix was studied. The thermal stability, electrical conductivity and morphology of nanocomposites were studied. The electrical conductivity of the obtained nanocomposite was very high at 0.7 S/m. see more This facile free radical polymerization provides a convenient route to achieve excellent dispersion and electrically conductive polymers.