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Hepatitis C virus (HCV) is the primary etiologic agent of liver cirrhosis or hepatocellular carcinoma. HCV elevated infection rates are mostly due to the lack of an accurate and accessible screening and diagnosis, especially in low- and middle-income countries. Conventional HCV diagnostic algorithm consists of a serological test followed by a nucleic acid test. This sequence of tests is time consuming and not affordable for low-resource settings. Nanotechnology have introduced new promising tests for the diagnose of infectious diseases. Based on the employment of nanoparticles and other nanomaterials which lead to highly sensitive and specific nanoscale tests, most of them target pathogen genome. Implementation of nanoscale tests, which are affordable, portable and easy to use by non-specialized personal, would improve HCV diagnosis algorithm. In this review, we have summed up the current emerging nanotechnology tools, which will improve actual screening and treatment programs, and help to reach HCV elimination proposal. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rigid polyurethane-aerogel foams are produced using isocyanate-aerogel dispersions of different concentrations. • Rheology shows that for concentrations above 2.5 wt% of aerogel the dispersion is in a percolated gel-like state. • The addition of aerogel progressively slows down the viscosity build-up and curing of the foam. • Percolated dispersions show less drainage of the reactive polymer and, in turn, lower fraction of mass in the struts of the final foam. The incorporation of silica aerogel particles into the isocyanate used to prepare Rigid Polyurethane composite foams drastically modifies its rheological behaviour. The isocyanate changes from being a Newtonian fluid of constant viscosity (0.3 Pa s at 25 °C) to a non-linear power-law material with complex viscosity decreasing from 104 to 101 Pa s with a slope −1 versus frequency. The change in response is caused by the formation of a percolated network of particles at contents above 2.5 wt% of aerogel. Moreover, the addition of aerogel significantly slows down the modulus-build up kinetics and vitrification of the matrix by approximately 4.5 min with every 1 wt% of aerogel added. For the foam with 3.0 wt% of aerogel, the combination of high viscosity at early reaction times coupled with the slow modulus build-up impedes the drainage which leads to a decrease in the fraction of material in the struts of the matrix. [ABSTRACT FROM AUTHOR]

A novel set-up for monitoring the gas diffusion process in polymers has been developed. This set-up is based on performing neutron radiography and tomography of polymeric materials under high pressures of gas. Information about the absorption kinetics of supercritical CO 2 was obtained. Additionally, solubility, diffusivity, and macroscopic changes in the dimensions of the samples can be in-situ obtained through the developed measurement technique. This novel approach can be very helpful to analyze the diffusion kinetics in a wide range of polymers. [Display omitted] • In-situ visualization of gas diffusion process in polymers. • Neutron radiography and tomography of gas diffusion in polymers. • In situ dimensions evolution of polymers under gas pressure. • In situ solubility and diffusivity evolution of polymers under gas pressure. [ABSTRACT FROM AUTHOR]

The modulus build-up and relative density evolution during the reactive foaming of four standard polyurethane formulations was monitored in-situ by Dynamic Mechanical Analysis (DMA) with a customised set-up in parallel plate geometry. The modulus increased from 0.01 MPa in the first minutes to over 1.2 MPa within 20 min. The set-up also enabled the recording of vitrification followed by curing times. These typically occur within 3 min of each other. The results of DMA are corroborated by measurements of the reaction kinetics with Infrared Spectroscopy. This goes to show that the modulus remains nearly unchanged during the stage of swiftest isocyanate conversion, while the point of gel conversion is accompanied by their increase. • DMA was applied to in-situ measure the modulus development of Rigid Polyurethane foams during foaming. • Employing a customised fixture density evolution was monitored simultaneously during the DMA experiments. • The modulus build-up profiles recorded with DMA were corroborated by measurements of the reaction kinetics. • Vitrification times can be inferred from the temporal evolution of the Loss modulus of the foams. [ABSTRACT FROM AUTHOR]

[Display omitted] The latent viral reservoir formed by HIV-1, mainly in CD4 + T cells, is responsible for the failure of antiretroviral therapy (ART) to achieve a complete elimination of the virus in infected individuals. We previously determined that CD4 + T cells from individuals with chronic myeloid leukemia (CML) on treatment with dasatinib are resistant to HIV-1 infection ex vivo. The main mechanism for this antiviral effect is the preservation of SAMHD1 activity. In this study, we aimed to evaluate the impact of dasatinib on the viral reservoir of HIV-infected individuals with CML who were on simultaneous treatment with ART and dasatinib. Due to the low estimated incidence of HIV-1 infection and CML (1:65,000), three male individuals were recruited in Spain and Germany. These individuals had been on treatment with standard ART and dasatinib for median 1.3 years (IQR 1.3–5.3 years). Reservoir size and composition in PBMCs from these individuals was analyzed in comparison with HIV-infected individuals on triple ART regimen and undetectable viremia. The frequency of latently infected cells was reduced more than 5-fold in these individuals. The reactivation of proviruses from these cells was reduced more than 4-fold and, upon activation, SAMHD1 phosphorylation was reduced 40-fold. Plasma levels of the homeostatic cytokine IL-7 and CD4 effector subpopulations TEM and TEMRA in peripheral blood were also reduced. Therefore, treatment of HIV-infected individuals with dasatinib as adjuvant of ART could disturb the reservoir reactivation and reseeding, which might have a beneficial impact to reduce its size. [ABSTRACT FROM AUTHOR]

• Low thermal conductivity foams prepared from recycled panel glass have been produced. • The mechanisms of heat transfer through glass foams of varying density and microstructure are evaluated. • A new model accounting for the scattering of radiation in foams with bimodal cellular structures is proposed. • The contribution of each heat transfer mechanism and the thermal conductivity of glass foams at different temperatures are predicted by the model. • The model is validated using experimental measurements and the deviation is below 2%. Glass foams are highly sustainable materials with enormous potential to replace traditional thermal insulators. Current research on glass foams is focused on improving thermal insulation by reducing density, but this is somehow a limited approach. Selecting the best approach to reduce thermal conductivity relies on establishing a detailed knowledge on the heat transfer mechanisms playing the most significant role. We have studied the mechanisms of heat transfer in a set of cathode-ray-tube (CRT) panel glass foams. The influence of relative density, cellular structure, gas composition, glass distribution between cell walls and struts, and radiation on heat transfer is addressed. From a detailed characterisation and state-of-the-art models, we have created a new analytical model adapted to the peculiarities of the foams under analysis. Additionally, the thermal conductivity for varying temperature conditions has been predicted. The obtained results point out to a significant contribution of the heat transfer by radiation for foams with porosities higher than 0.96. The predicted values of thermal conductivity indicate the existence of a plateau region at high porosities. Temperature is proven to shift the contributions of heat transfer, increasing the weight of radiation and gas conduction. The predictions of the new analytical model have been contrasted with experimental measurements of the thermal conductivity at different densities and temperatures obtaining differences below 2%. [ABSTRACT FROM AUTHOR]

• Rigid polyurethane foams with different contents of aerogel are prepared. • Cell nucleation is enhanced by the presence of aerogel particles. • Degeneration mechanisms – as observed in-situ – are induced by the presence of particles larger than a few microns. • Low contents of aerogel boost polymerization reaction preventing coalescence and drainage. Water blown rigid polyurethane (RPU) composite foams were produced using different concentrations of nanoporous silica aerogel micrometric powder (0.5, 1 and 3 wt%). The effect of these particles on the foaming kinetics was analysed from a physical and chemical viewpoint. On the physical side, the foaming process was studied by in-situ X-ray radioscopy. The inclusion of aerogel particles in the system delays the foam expansion and enhances the nucleation of cells. However, high amounts of these particles (3 wt%) lead to intense cell coalesce during foam evolution. On the chemical side, the reaction kinetics was investigated by in-situ FTIR spectroscopy and reaction temperature measurements. The addition of low contents of aerogel (below 3 wt%) reduces the conversion of isocyanate while favouring the generation of urethane groups, which explains the higher density of the foams with low aerogel contents. However, the foam with high contents of aerogel (3 wt%) does not change the reaction balance in comparison to the reference. Therefore, this foam presents similar expansion and density to those of the unfilled foam (Reference). Furthermore, higher reaction temperatures were reached by the reference foam during the foaming process, and higher dissipation speeds of these temperatures were detected for the foams containing aerogel with respect to those of the reference foam. [ABSTRACT FROM AUTHOR]

• Polyols functionalized with GO (GO-f) and filled with GO (GO-d) are used. • The foaming of RPU foams with GO-f or GO-d is followed by X-Ray radioscopy. • The cellular structure of RPU foams are improved by incorporation of GO-f. • GO-f offers better results than GO-d. Fillers can be dispersed in polyurethane (PU) components to produce PU foams with improved properties by different methods. Herein, graphene oxide (GO) is chemically linked to polyol chains in order to suppress fillers agglomeration. Then the foaming behaviour of rigid polyurethane (RPU) foams from polyols functionalized with GO (GO-f) is compared with the one of RPU foams containing GO dispersed in the polyol (GO-d) by high shear mixing. Relative density, cell size, and cell nucleation density of the RPU foam nanocomposites are monitored during the foaming process by using X-ray radioscopy. The results obtained demonstrate that the use of polyol functionalized with GO-f offers a high improvement of the cellular structure and also makes the results more reproducible. [ABSTRACT FROM AUTHOR]

Gender-specific consequences after HCV eradication are unexplored. MicroRNAs (miRNAs) play a crucial role in the immune response against viral infections. However, few have highlighted miRNA role in sex-biased disease or therapy response. We aim to assess gender differences reflected in the miRNA expression of HIV/HCV-coinfected patients who achieve sustained virological response (SVR) with direct acting antivirals (DAAs). We conducted a prospective study of miRNA expression in PBMCs from 28 chronic HIV/HCV-coinfected patients (HIV/HCV) at baseline and after achieving SVR with DAAs. Sixteen HIV-monoinfected patients (HIV) and 36 healthy controls (HC) were used as controls. Identification of significant differentially expressed (SDE) miRNAs was performed with generalized linear model and mixed GLMs. We also explored putative dysregulated biological pathways. At baseline , the HIV/HCV patients showed differences in the miRNA profile concerning the HIV group (165 and 102 SDE miRNAs for males and females, respectively). Gender-stratified analysis of HIV/HCV group at baseline versus at SVR achievement showed higher differences in males (80 SDE miRNAs) than in females (55 SDE miRNAs). After SVR, HIV/HCV group showed similar values to HIV individuals, especially in females (1 SDE miRNA). However, ten miRNAs in males remained dysregulated, which were mainly involved in cancer, fatty acid, and inflammatory pathways. Taken together, our results show gender-biased dysregulation in the miRNA expression profile of PBMCs after HCV eradication with DAAs. These differences were normalized in females, while miRNA profile and their target-related pathways in males lack of normalization, which may be related to a high-risk of developing liver-related complications. [Display omitted] [ABSTRACT FROM AUTHOR]