Recording of PIV images on photothermoplastic plates

In this paper we explore the possibility of utilizing commercially available photothermoplastic plates as recording support in Particle Image Velocimetry (PIV), to allow real time analysis of recorded data. An experimental apparatus has been developed which allows holographic recording and reconstruction of simulated PIV images. We show that double exposed photothermoplastic plates can successfully be analysed provided that a suitable recording/reconstruction scheme is used.     

EPR study of the surface basicity of calcium oxide. 3. Surface reactivity and nonstoichiometry

High surface area polycrystalline calcium oxide forms ozonide O3- ions upon O2 adsorption and NO3(2-) anions under low pressures of NO. Both radical anions, detected by electron paramagnetic resonance (EPR), are not observed in the case of the homologous magnesium oxide. This behavior reveals the presence, in CaO, of anomalies with respect to the ideal composition of an ionic oxide which are identified in terms of two main types of defects. The first type consists of positive holes dispersed in the bulk and originated by the unavoidable presence of Na+ ions in the composition of the solid. The decomposition of the surface ozonide shows the formation of a transient surface stabilized O- (the chemical notation of a positive hole associated to an oxide ion) which is for the first time reported at the surface of CaO. The second type of defect consists of surface peroxide groups (present at particular surface sites where they are formed by pairing of two distinct O-) which react with nitric oxide (NO) yielding NO3(2-) radical anions. The presence of peroxide is not related to the presence of impurities but, rather, to a certain propensity of the solid to form such ions at the surface along the dehydration process.     

Antisense-mediated isoform switching of steroid receptor coactivator-1 in the central nucleus of the amygdala of the mouse brain

Background

Antisense oligonucleotide (AON)-mediated exon skipping is a powerful tool to manipulate gene expression. In the present study we investigated the potential of exon skipping by local injection in the central nucleus of the amygdala (CeA) of the mouse brain. As proof of principle we targeted the splicing of steroid receptor coactivator-1 (SRC-1), a protein involved in nuclear receptor function. This nuclear receptor coregulator exists in two splice variants (SRC-1a and SRC-1e) which display differential distribution and opposing activities in the brain, and whose mRNAs differ in a single SRC-1e specific exon.

Methods

For proof of principle of feasibility, we used immunofluorescent stainings to study uptake by different cell types, translocation to the nucleus and potential immunostimulatory effects at different time points after a local injection in the CeA of the mouse brain of a control AON targeting human dystrophin with no targets in the murine brain. To evaluate efficacy we designed an AON targeting the SRC-1e-specific exon and with qPCR analysis we measured the expression ratio of the two splice variants.

Results

We found that AONs were taken up by corticotropin releasing hormone expressing neurons and other cells in the CeA, and translocated into the cell nucleus. Immune responses after AON injection were comparable to those after sterile saline injection. A successful shift of the naturally occurring SRC-1a:SRC-1e expression ratio in favor of SRC-1a was observed, without changes in total SRC-1 expression.

Conclusions

We provide a proof of concept for local neuropharmacological use of exon skipping by manipulating the expression ratio of the two splice variants of SRC-1, which may be used to study nuclear receptor function in specific brain circuits. We established that exon skipping after local injection in the brain is a versatile and useful tool for the manipulation of splice variants for numerous genes that are relevant for brain function.     

Multi-diagnostic approach to characterize the onset of formation of nanoparticles in a premixed laminar ethylene/air flame

The onset of formation of nanoparticles in a premixed laminar ethylene/air flame was studied using optical and non-optical diagnostic techniques. The optical techniques (Visible Imaging, Spectroscopic analysis of optical emission, Laser Induced Incandescence and Optical Extinction) were checked against the direct measurement of particles size distribution done with a commercial sampler. The diagnostic techniques were set up on a standard burner (McKenna). The combustion conditions were varied by tuning two experimental parameters: the equivalent ratio Φ and the cold gases velocity v. Values of Φ were investigated in the range 1.3 to 2.2, in combination with cold unburned gas velocities of 5, 7 and 10 cm/s. By varying the combustion conditions, a transition in the signal detected by the different techniques was observed. The transition was put in correspondence with the sensitivity of the given technique to the onset of the nanoparticles formation. A comparison of the sensitivity of the different techniques was performed.     

Transfer measurements for the Ti+Ni systems at near barrier energies

Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies. Coupled channel calculations incorporating couplings to 2⁺ and 3⁻ states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer were carried out for ^46,48Ti+⁶¹Ni systems. The present paper gives the results of these studies.