The effect of series resistance on calculation of the interface state density distribution in Schottky diodes

This work presents an attempt related to the importance of the fact that the series resistance value is considered in calculating the inter-face state density distribution from the non-ideal forward bias current–voltage (I-V) characteristics of Au/n-Si Schottky barrier diodes (SBDs). To examine the consistency of this approach, Au/n-Si SBDs with Si bulk thicknesses of 200 and 400μm have been prepared. Both diodes showed non-ideal I-V behaviour with ideality factors of 1.14 and 1.12, respectively, and thus it has been thought that the diodes have a metal–interface layer–semiconductor configuration. At the same energy position near the bottom of the conduction band, the interface state density (N _SS) values, without taking into account the series resistance value of the devices, are almost one order of magnitude larger than the N _SS values obtained taking into account the series resistance value.     

Mathematical modelling of sound transmission loss performances of different coloured surfaces coated with polyurethane-based paint

ABSTRACT

The aim of this study is to investigate the effect of morphologies and the structure of polyurethane-based coatings created by different colour pigments, on sound transmission loss properties. To achieve this goal, coatings were created in different concentrations of 5%, 7% and 9% with red, green, orange and yellow pigments. The coatings were applied on glass surfaces and the sound transmission loss was measured by an experimental arrangement containing a microphone and a decibel meter. The effect of surface tension energy, surface roughness, reflection percentages and concentration of pigments were found to be negligible on the sound transmission loss, whereas the LAB colour codes have a determining effect. In the scope of this study, a new method and mathematical model were created to help measure the sound transmission loss on a surface, in which sound signal was carried with a laser beam via a system created in the laboratory.     

Proprotein Convertase Subtilisin Kexin Type 9 Inhibitors Reduce Platelet Activation Modulating ox-LDL Pathways

Background: Proprotein convertase subtilisin kexin type 9 inhibitors (PCSK9i) lower LDL-cholesterol and slow atherosclerosis preventing cardiovascular events. While it is known that circulating PCSK9 enhances platelet activation (PA) and that PCSK9i reduce it, the underlying mechanism is not still clarified. Methods: In a multicenter before–after study in 80 heterozygous familial hypercholesterolemia (HeFH) patients on treatment with maximum tolerated statin dose ± ezetimibe, PA, soluble-NOX2-derived peptide (sNOX2-dp), and oxidized-LDL (ox-LDL) were measured before and after six months of PCSK9i treatment. In vitro study investigates the effects of plasma from HeFH patients before and after PCK9i on PA in washed platelets (wPLTs) from healthy subjects. Results: Compared to baseline, PCSK9i reduced the serum levels of LDL-c, ox-LDL, Thromboxane (Tx) B2, sNOX2-dp, and PCSK9 (p < 0.001). The decrease of TxB2 correlates with that of ox-LDL, while ox-LDL reduction correlated with PCSK9 and sNOX2-dp delta. In vitro study demonstrated that wPLTs resuspended in plasma from HeFH after PCSK9i treatment induced lower PA and sNOX2-dp release than those obtained using plasma before PCSK9i treatment. This reduction was vanished by adding ox-LDL. ox-LDL-induced PA was blunted by CD36, LOX1, and NOX2 inhibition. Conclusions: PCSK9i treatment reduces PA modulating NOX2 activity and in turn ox-LDL formation in HeFH patients.     

A face recognition system based on automatically determined facial fiducial points

In this paper, a completely automatic face recognition system is presented. The method works on color images: after having localized the face and the facial features, it determines 24 facial fiducial points, and characterizes them applying a bank of Gabor filters which extract the peculiar texture around them (jets). Recognition is realized measuring the similarity between the different jets. The system is inspired by the elastic bunch graph method, while it does no assumption on the scale, pose, and the background. Comparison with standard algorithms is presented and discussed.     

Biomodification of fats and oils: Trials withCandida lipolytica

Various oil-accumulating yeasts were tested for their ability to produce lipase and live on fats and oils as carbon sources. Of these,Candida lipolytica seemed most promising, and the possibility was explored of modifying fats and oils by fermenting them withC. lipolytica and extracting the modified oil deposited in the yeast cells. Oxygen was required for the growth of yeast on fats and oils, but unless the oxygen level was controlled at a low value after cell populations peaked, most of the substrate oil was converted to citrates rather than accumulating as oil. Oil accumulation byC. lipolytica from a corn oil substrate was slightly depressed by excess nitrogen in the medium. The yeasts were able to use about 18 g/l of oil in 72 hr. At substrate oil levels greater than 18 g/l, the dry yeasts were 60% oil, and about 45–57% of the substrate oil was recovered as yeast oil. The fatty acid composition of the yeast oil was quite similar to that of the substrate oil under optimum conditions of deposition. Sterols, but not tocopherols, were transferred from the substrate to the yeast oil.Candida lipolytica oil was high in free fatty acids. The greatest potential for biomodification by fermentation withC. lipolytica seems to be in altering glyceride structure. Journal Paper No. J-11337 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Project No. 2493.     

Mutual interactions between HIV-1 and cytokines in adherent cells during acute infection

Intracerebroventricular (i.c.v.) infusions of angiotensin II (AII) reliably induced c-fos expression in the supraoptic (SON) and paraventricular (PVN) nuclei, as well as other areas of the basal forebrain including the OVLT, subfornical organ (SFO), and bed nucleus (BNST). Double-labelling showed that AII-induced c-fos was observed in both vasopressin (AVP-) and oxytocin (OXY)-containing neurons of the SON and PVN in male rats. Allowing rats to drink water after AII infusions suppressed c-fos expression both AVP- and OXY-stained magnocellular neurons. Intragastric infusions of water were also effective, showing that oro-pharyngeal stimuli were not critical. Maximal suppression occurred in rats in whom water had been infused intragastrically about 5 min before i.c.v. AII infusions, suggesting that changes in osmolarity were responsible. i.c.v. AII also induced c-fos expression in a number of brainstem structures, including the solitary nucleus (NTS), lateral parabrachial nucleus (LPBN), locus coeruleus (LC), and the area postrema (AP). These results indicate that AVP and OXY-containing neurons in the magnocellular parts of the SON and PVN alter their immediate-early gene response to AII after water intake, and that this does not depend upon oro-pharyngeal factors. Furthermore, AII can induce c-fos expression in a number of brainstem nuclei associated with autonomic function, and these do not respond to water intake.     

Antioxidants in spring leaves of Oxalis acetosella L.

Oxalis acetosella L. is a common, edible wild plant native to the northern hemisphere. The contents of selected antioxidants, and the antioxidant capacity of young and old spring leaves of O. acetosella, were evaluated. The present study reports foliar contents of ascorbic acid, tocopherols, carotenoids, chlorophyll, flavonoids, phenolic acids and total phenolics, and compares the nutritional value of O. acetosella with other cultivated and wild plants. The composition of foliar antioxidants was found to depend on leaf age. On the other hand, the antioxidant capacity of old leaves were in the same range as young leaves. A comparison between O. acetosela with lettuce analysed in our study, and with numerous cultivated and wild edible plants from other studies, showed that O. acetosella is very rich in β-carotene, ascorbic acid, tocopherols and xanthophylls, and that it is one of the best sources of flavonoids (flavonol glycosides and flavan-3-ols), especially rutin. Therefore, O. acetosella is a potentially important dietary source of antioxidants.     

Gas chromatography screening of bioactive phytosterols from mono-cultivar olive oils

Phytosterols (PS) from nine samples of olive oil from Olea europaea L., the Carolea, Cassanese and Coratina mono-cultivars, have been analyzed by gas chromatography. Coratina virgin olive oil (VOO) from the month of November showed highest contents of β-sitosterol (5491 mg kg⁻¹) and Δ⁵ avenasterol (1767 mg kg⁻¹). Olive pomace oil had the lowest total content of all PS, when compared to VOO. These results suggests that, PS can be an important regulatory factor for the functional quality of olive oil along the agro-industry chain from the orchard to nutraceutical.     

Towards a methodology for estimating strength and collapse mechanism in masonry arches strengthened with fibre reinforced polymer applied on external surfaces

Assessment of the effects of the application of advanced materials and new technologies on traditional structures has assumed a major relevance within the ongoing debate on the preservation of historic buildings. The aim of the present paper is to discuss the validity of analytical models, by means of experimental investigations carried out on masonry arches reinforced with CFRP strips, bonded at the intrados or extrados with distinct configurations. A theoretical prediction of ultimate strength for the different reinforcement configurations was derived in agreement with the occurrences observed during the experiments (masonry crushing, FRP rupture, debonding, sliding along the mortar joint). The results of the experimental trials allowed not only to validate the proposed analytical derivations but also to evaluate the impact of different reinforcement configurations on the strength of masonry arches and then to deduce considerations on sizing criteria for the CFRP strengthening of traditional masonry structures.