To evaluate choroidal structural changes occurring over time in geographic atrophy (GA) secondary to age-related macular degeneration using choroidal vascularity index (CVI).
Enhanced-depth imaging ...optical coherence tomography scans of 34 patients with GA and 32 control subjects were retrospectively analyzed. Data were collected at baseline and after a mean follow-up of 18.3 ± 8.3 months. Choroidal images were binarized using the ImageJ software, and the luminal area and stromal area were segmented. Choroidal vascularity index was defined as the ratio of luminal area to total choroid area.
Patients with GA showed significantly lower values of CVI, total choroid area, luminal area, and subfoveal choroidal thickness compared to control subjects (65.83 ± 3.95 vs. 69.33 ± 3.11, P < 0.001; 0.400 ± 0.239 mm vs. 0.491 ± 0.132, P = 0.006; 0.263 ± 0.152 mm vs. 0.340 ± 0.094, P = 0.002; 185.2 ± 79.8 µm vs. 216.8 ± 58.8 µm, P = 0.036, respectively). Best-corrected visual acuity was significantly correlated only with choroidal thickness (R = -0.509; P = 0.002). During the follow-up period in patients with GA, subfoveal choroidal thickness decreased from 185.2 ± 79.8 to 152.2 ± 73.1 (P = 0.001), stromal area increased from 0.138 ± 0.090 mm to 0.156 ± 0.068 (P = 0.028), and CVI decreased from 65.83 ± 3.95 to 62.24 ± 3.63 (P < 0.001).
This study showed for the first time that CVI is reduced in patients with GA, and that this metric further worsened during the follow-up period.
The bioartificial kidney (BAK) aims at improving dialysis by developing 'living membranes' for cells-aided removal of uremic metabolites. Here, unique human conditionally immortalized proximal tubule ...epithelial cell (ciPTEC) monolayers were cultured on biofunctionalized MicroPES (polyethersulfone) hollow fiber membranes (HFM) and functionally tested using microfluidics. Tight monolayer formation was demonstrated by abundant zonula occludens-1 (ZO-1) protein expression along the tight junctions of matured ciPTEC on HFM. A clear barrier function of the monolayer was confirmed by limited diffusion of FITC-inulin. The activity of the organic cation transporter 2 (OCT2) in ciPTEC was evaluated in real-time using a perfusion system by confocal microscopy using 4-(4-(dimethylamino)styryl)-N-methylpyridinium iodide (ASP(+)) as a fluorescent substrate. Initial ASP(+) uptake was inhibited by a cationic uremic metabolites mixture and by the histamine H2-receptor antagonist, cimetidine. In conclusion, a 'living membrane' of renal epithelial cells on MicroPES HFM with demonstrated active organic cation transport was successfully established as a first step in BAK engineering.
► 3D irregular rough surfaces produce higher effects than those observed over 2D. ► Effective slope is a geometrical parameter representative of the roughness effects. ► 3D rough surfaces enhance the ...turbulence isotropization. ► 2D and 3D irregular roughness partially support the wall similarity. ► Irregular rough surfaces shear some features with regular rough walls.
Wall-resolved Large Eddy Simulation of fully developed turbulent channel flows over two different rough surfaces is performed to investigate on the effects of irregular 2D and 3D roughness on the turbulence. The two geometries are obtained through the superimposition of sinusoidal functions having random amplitudes and different wave lengths. In the 2D configuration the irregular shape in the longitudinal direction is replicated in the transverse one, while in the 3D case the sinusoidal functions are generated both in streamwise and spanwise directions. Both channel walls are roughened in such a way as to obtain surfaces with statistically equivalent roughness height, but different shapes. In order to compare the turbulence properties over the two rough walls and to analyse the differences with a smooth wall, the simulations are performed at the same Reynolds number Reτ=395. The same mean roughness height h=0.05δ (δ the half channel height) is used for the rough walls.
The roughness function obtained with the 3D roughness is larger than in the 2D case, although the two walls share the same mean height. Thus, the considered irregular 3D roughness is more effective in reducing the flow velocity with respect to the 2D roughness, coherently with the literature results that identified a clear dependence of the roughness function on the effective slope (see Napoli et al. (2008)), higher in the generated 3D rough wall. The analysis of higher-order statistics shows that the effects of the roughness, independently on its two- or three-dimensional shape, are mainly confined in the inner region, supporting the Townsend’s wall similarity hypothesis. The tendency towards the isotropization is investigated through the ratio between the resolved Reynolds stress components, putting in light that the 3D irregular rough wall induces an higher reduction of the anisotropy, with respect to the 2D case.
•Peaks of the irregularities produce higher effects than those generated by cavities.•Cavity roughness causes an increase of friction drag.•Roughness crests are responsible of the pressure drag ...augmentation.•Irregular rough walls support the Townsend similarity hypothesis.
Large Eddy Simulations (LES) are carried out to investigate on the mean flow in turbulent channel flows over irregular rough surfaces. Here the attention is focused to selectively investigate on the effect induced by crests or cavities of the roughness. The irregular shape is generated through the super-imposition of sinusoidal functions having random amplitude and four different wave-lengths. The irregular roughness profile is reproduced along the spanwise direction in order to obtain a 2D rough shape. The analysis of the mean velocity profiles shows that roughness crests induce higher effect in the outer-region whereas roughness cavities cause the highest effects in the inner-region with a reduced effect in the external region. The numerical simulations have been carried out at friction Reynolds number Reτ=395. Similar results have been found for the higher order statistics: turbulence intensities or shear stresses. The analysis of the Reynolds stress anisotropy tensor confirms the existence of specific roles of cavities and crests in the turbulence modulation.
•Blood oranges are appreciated for their high nutraceutical value.•Cold treatment is able to extend Tarocco shelf life and increase anthocyanin levels.•Cold treatment permits to use Tarocco fruits ...for fresh-chilled juice during summer.
Tarocco “Sant’Alfio” is a late ripening blood orange cultivar. Blood oranges are more and more appreciated from consumers for their high nutraceutical value due to the presence of bioactive compounds including vitamin C, polyphenols, flavonoids and hydroxycinnamic acids.
The aim of this work is to set up a reliable protocol for postharvest storage of the very-late Tarocco “Sant’Alfio” orange to prolong the availability of this product in the market to be used for fresh chilled orange juice production.
Fruits were subjected to three storage treatments (20days at 1°C plus 50days at 4°C; 70days at 4°C; 70days at 20°C). The results indicate that cold treatments, in particular at 4°C constantly, can extend Tarocco “Sant’Alfio” shelf life enhancing total anthocyanin content. The defined protocols allow prolonging market availability of a high value product and could induce relevant benefits for the citrus industry and consumers.
•3D irregular rough surfaces produce higher effects than those observed over 2D.•Effective slope is a geometrical parameter representative of the roughness effects.•Roughness function scales with ES ...through a logarithmic law.•2D and 3D irregular roughness selectively modify the turbulence structure.•2D rough surface hide some feature observed over 3D rough wall.
The effects of wall roughness on turbulence structure modifications were explored by numerical experiments, carried out using Large Eddy Simulation techniques. The wall geometry was made using an archetypal artificial method, thus to achieve irregular two- and three-dimensional shapes. The proposed roughness shapes are highly irregular and are characterised by high and small peaks, thus it can be considered a practical realistic roughness. Their effects are analysed comparing the turbulence quantities over smooth, 2D and 3D rough walls of fully developed channel flow at relatively low friction Reynolds number Reτ=395. Both transitional and fully rough regimes have been investigated. The two rough surfaces were built in such a way that the same mean roughness height and averaged mean deviation is obtained. Despite of this, very different quantitative and qualitative results are generated. The analysis of the mean quantitative statistics and turbulence fluctuations shows that deviations are mainly concentrated in the inner layer. These results support the Townsend’s similarity hypothesis. Among the geometrical parameters, which characterise the wall geometries, roughness slope correlates well with the roughness function ΔU+. Specifically, a logarithmic law is proposed to predict the downward shift of the velocity profile for the transitional regime. Instantaneous view of turbulent organised structures display differences in small-scale structures. The flow field over rough surfaces is populated with coherent structures shorter than those observed over flat planes. The comparative analysis of both streaks and wall-normal vortical structures shows that 2D and 3D irregularities have quite different effects. The results highlight that 3D rough wall are representative of a more realistic surface compared to idealised 2D roughness.
Normally-on (depletion mode) and normally-off (enhancement mode) diamond Junction Field Effect Transistors (JFETs) have been analyzed by means of a commercially available TCAD software. First, the ...parameters used for describing the incomplete ionization, avalanche, and mobility models in diamond have been discussed and assessed against the state-of-the-art. The on- and off-state electrical characteristics of diamond JFETs have been simulated with the suggested parameter values and matched with a set of available experimental data. Secondly, an optimization technique which can improve the performance of an enhancement mode diamond JFET that operates in the unipolar conduction regime has been proposed. This method takes into account the unique properties and limitations of diamond and highlights the main issues that can arise from the design of a normally-off diamond JFET. In particular, the crucial effect of the high temperature on the performance of the normally-off JFET has been investigated. The adopted technique is mainly based on a design of TCAD experiments and no mathematical algorithms have been developed for the calculation of the optimized set of parameters.
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•TCAD optimization of a unipolar mode normally-off (enhancement mode) diamond JFET•Normally-off diamond JFETs can become normally-on at high operational temperatures.•Incomplete ionization dependence on the electric field and on the temperature, cannot be neglected in the design.•Simulated device can outperform the state of the art unipolar mode diamond JFET.
This paper presents a short review of the evidence - both experimental and theoretical - of the formation of dissipative structures in liquid water induced by three kinds of physical perturbations ...having a low energy content: extremely diluted solution (EDS), iteratively filtered water (IFW), and iteratively nafionated water (INW). Particular attention is devoted to the very recent discovery that such structures are tremendously persistent even in the solid phase: large ponderal quantities of supramolecular aggregates of water (with each nucleus hundreds of nanometers in size) have been observed - at ambient pressure and temperature - using easily-reproducible experimental methods. The nature of these dissipative structures is analyzed and explained in terms of the thermodynamics of far-from-equilibrium systems and irreversible processes, showing their spontaneous quantum origin. Are these kinds of structures the matrix itself of life?.
The vectorial role of blood-sucking arthropods, other than mosquitoes, has been explored for Dirofilaria immitis and Dirofilaria repens which are filarioids of increasing interest due to their ...zoonotic potential. Given the expansion of canine heartworm infection in southern Europe due to D. immitis and the report of the infection in Linosa Island (Sicily, Italy), we investigated and focused on the potential involvement of Culicoides spp. in Dirofilaria spp. transmission as well as the blood-meal source in Dirofilaria spp. molecularly positive biting midges. Out of 1791 specimens collected 1773 were morphologically and molecularly identified as Culicoides paolae and 18 as Culicoides obsoletus complex. Of the 1596 females, 4 (0.26%) parous C. paolae tested positive for D. immitis and D. repens (i.e. 2 Culicoides specimens for each filarial species), of which D. immitis-positive samples fed on both humans and dogs and D. repens-positive samples fed only on humans. The detection of D. immitis and D. repens DNA in Culicoides midges suggests their potential involvement in the epidemiology of the filarial nematodes, which may be of medical and veterinary importance in hyper-endemic areas. Findings of this study shed new light on the epidemiology of Dirofilaria spp. infections indicating that further investigations are needed.
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