Light Supports Neurite Outgrowth of Human Neural Progenitor Cells In Vitro: The Role of P2Y Receptors

The purpose of this study was to compare the effects of growth factors and 810-nm-wavelength light on the differentiation of normal human neural progenitor cells (NHNPCs) in vitro. Although growth factors are routinely used to study neural stem and progenitor cells in vitro, to date, light has not been used as a replacement for growth factors. This study demonstrates that NHNPCs are not only capable of being sustained by light in the absence of growth factors, but that they are also able to differentiate normally as assessed by neurite formation. The NHNPCs had an up-regulation in the expression of endogenous fibroblast growth factor-2, brain derived neurotrophic factor, and nerve growth factor in response to the light. Suramin, a nonselective P2 receptor antagonist, significantly decreased neurite outgrowth, and P2Y2 and P2Y11 receptors were found to be expressed by the NHNPCs by immunolabeling. Based on these findings, the mechanism by which light supports the NHNPC differentiation is hypothesized to be due to increases in adenosine triphosphate acting via P2Y receptors.     

Microstructures of thin and thick slurry aluminide coatings on Inconel 690

Two slurry aluminide coatings are produced on the Ni-base super alloy Inconel 690 by applying two different thicknesses of the same slurry on to the 690 substrate, followed by a two-step heat-treatment. The resulting thin aluminide coating consists of a single layer of Ni-rich β-NiAl matrix containing few large Cr precipitates with a high P content. The thick aluminide coating has a precipitate free inner layer of Ni-rich β-NiAl. An outer layer of Al-rich β-NiAl with many α-Cr precipitates has formed as well. The present metallurgical characterization shows a significant influence of slurry thickness on the morphology and composition of the coatings formed during heat treatment.     

Effects of Backfilling on Cable Ampacity Analyzed With the Finite Element Method

Expressions for computing the external thermal resistance (T₄) of buried cables, in both the IEEE and the IEC standards, are applicable to a limited number of installation geometries. In this paper, a method for the computation of T₄ using the finite element approach is presented. With this method, a parametric study on how cable ampacity is affected by different configurations of the backfills is performed. The obtained results are compared with those of the IEC and IEEE standards (Neher-McGrath) and published extensions by El-Kady and Horrocks. Important differences can be observed for nonstandardized situations.     

Chemical composition and mass emission factors of candle smoke particles

The aim of this study is to investigate the physical and chemical properties of particle emissions from candle burning in indoor air. Two representative types of tapered candles were studied during steady burn, sooting burn and smouldering (upon extinction) under controlled conditions in a walk-in stainless steel chamber. Steady burn emits relatively high number emissions of ultrafine particles dominated by either phosphates or alkali nitrates. The likely source of these particles is flame retardant additives to the wick. Sooting burn in addition emits larger particles mainly consisting of agglomerated elemental carbon. This burning mode is associated with the highest mass emission factors. Particles emitted during smouldering upon extinction are dominated by organic matter. A mass closure was illustrated for the total mass concentration, the summed mass concentration from chemical analysis and the size-integrated mass concentration assessed from number distribution measurements using empirically determined effective densities for the three particle types.     

Structural, optical, and electrical properties of indium-doped cadmium oxide films prepared by pulsed filtered cathodic arc deposition

Indium-doped cadmium oxide (CdO:In) films were prepared on glass and sapphire substrates by pulsed filtered cathodic arc deposition (PFCAD). The effects of substrate temperature, oxygen pressure, and an MgO template layer on film properties were systematically studied. The MgO template layers significantly influence the microstructure and the electrical properties of CdO:In films, but show different effects on glass and sapphire substrates. Under optimized conditions on glass substrates, CdO:In films with thickness of about 125 nm showed low resistivity of 5.9 × 10^?5 Ωcm, mobility of 112 cm²/Vs, and transmittance over 80 % (including the glass substrate) from 500 to 1500 nm. The optical bandgap of the films was found to be in the range of 2.7 to 3.2 eV using both the Tauc relation and the derivative of transmittance. The observed widening of the optical bandgap with increasing carrier concentration can be described well only by considering bandgap renormalization effects along with the Burstein–Moss shift for a nonparabolic conduction band.     

Policy SEA: lessons from development co-operation

This professional practice report reflects upon lessons learned from piloting and evaluating an innovative approach to policy strategic environmental assessment (SEA) in developing countries. The primary analytical focuses of the approach are institutions and governance characteristics, plus it places strong emphasis on learning. The piloting provides valuable insights about the conduct of SEA at the policy level and in socio-political where there is limited experience with SEA. From our observations we reflect upon the importance of appropriate ownership of an SEA; the practical implications of working in contested political environments; the challenges in using SEA as a tool to promote good governance; and the centrality of a long-term perspective to environmental and social mainstreaming.