Real-time thermography system for composite welding:Undamaged baseline approach

The aerospace industry's current focus on recyclable materials and low-cost processes has accelerated research and implementation of thermoplastics matrix composites (TPC). In the last decades, researchers have researched weldability of these materials as a valid alternative to conventional mechanical fastening and adhesives, for improving the strength of the joint. Automatic induction welding of carbon fiber TPCs is one of the most promising techniques due to its numerous benefits, such as elevated energy efficiency and highly localised heat. As for all the manufacturing techniques, the importance of efficiently detecting the presence of defects during TPCs welding has pushed the need for automated real-time non-destructive evaluation (NDE) systems. This paper focuses on the development of an efficient NDE technique able to detect the presence of alterations and defects in real-time during the welding process. This technique relies on Infrared (IR) active thermography inspections performed using the induction welding heat as the source and an undamaged baseline methodology to detect differences in the heat field. The procedure was experimentally analysed by means of an apparatus capable of automatic welding of samples, performing the real-time NDE during the process. Results show the efficiency of the method to localise the damaged area and characterise the defects during the welding. The undamaged baseline methodology was proven to better clarify shape and location of defects, allowing for an efficient detection of damaged samples and areas where more detailed inspections can be performed after the welding process by means of the same IR apparatus.</p

Interactions between permeation and gating in the TMEM16B/anoctamin2 calcium-activated chloride channel

At least two members of the TMEM16/anoctamin family, TMEM16A (also known as anoctamin1) and TMEM16B (also known as anoctamin2), encode Ca2+-activated Cl- channels (CaCCs), which are found in various cell types and mediate numerous physiological functions. Here, we used whole-cell and excised inside-out patch-clamp to investigate the relationship between anion permeation and gating, two processes typically viewed as independent, in TMEM16B expressed in HEK 293T cells. The permeability ratio sequence determined by substituting Cl- with other anions (PX/PCl) was SCN- > I- > NO3- > Br- > Cl- > F- > gluconate. When external Cl- was substituted with other anions, TMEM16B activation and deactivation kinetics at 0.5 μM Ca2+ were modified according to the sequence of permeability ratios, with anions more permeant than Cl- slowing both activation and deactivation and anions less permeant than Cl- accelerating them. Moreover, replacement of external Cl- with gluconate, or sucrose, shifted the voltage dependence of steady-state activation (G-V relation) to more positive potentials, whereas substitution of extracellular or intracellular Cl- with SCN- shifted G-V to more negative potentials. Dose-response relationships for Ca2+ in the presence of different extracellular anions indicated that the apparent affinity for Ca2+ at +100 mV increased with increasing permeability ratio. The apparent affinity for Ca2+ in the presence of intracellular SCN- also increased compared with that in Cl-. Our results provide the first evidence that TMEM16B gating is modulated by permeant anions and provide the basis for future studies aimed at identifying the molecular determinants of TMEM16B ion selectivity and gating. © 2014 Betto et al

Effect of Different Irrigating Solutions and Endodontic Sealers on Bond Strength of the Dentin - Post Interface with and without Defects.

Abstract Aims. To investigate how the interfacial shear strength of the dentin – post interface with and without defects changes for different combinations irrigant/sealer. Methods. In forty human decoronated and instrumented teeth, fibreglass posts were in-serted. The obtained root segments were randomly assigned to four different groups ac-cording to the irrigant adopted and the cement used to seal the root canal. The root segments were processed for metyl-methacrylate embedding. Serial sections were obtained and sub-mitted to histomorphometric analyses in order to observe any defect of adhesion at the dentin – post interface and to measure the defects’ dimension. The serial sections were also submitted to micro-push-out test. The measured shear strength values were subjected to statistical analysis by one-way ANOVA. The values of bond strength determined for the defective samples were correlated with the dimension of the defects. Finite element models were built to interpret and corroborate the experimental findings. Results. ANOVA showed that the generic combination irrigant/sealer does not affect the interfacial shear strength values. The bond strength of the samples without defects was av-eragely twice as large as that of the defective samples. The defects occupying more than 12 % of the total transverse section area of the endodontic cement layer led to a reduction of the bond strength of about 70 %. The predictions of the finite element models were in agreement with the experimental results. Conclusion. Defects occupying less than 2 % of the total transverse section area of the cement layer were shown to be acceptable as they have rather negligible effects on the shear strength values. Technologies/protocols should be developed to minimize the number and the size of the defects

Survival of patients with HCV cirrhosis and sustained virologic response is similar to the general population.

Background &amp; Aims: Life expectancy of patients with compensated hepatitis C virus (HCV) cirrhosis achieving sustained virologic response (SVR) is limited by liver events as compared to the general population. Thus, survival benefit of SVR remains to be measured. Methods: The study includes prospective surveillance data from three cohorts of Italian patients with compensated HCV cirrhosis who achieved SVR on an interferon-based (IFN) regimen, compared to simultaneously observed non-SVR, untreated and decompensated patients. Overall survival was calculated from the date of start of IFN to death. The number of deaths expected during the at-risk period was determined by applying age- and sex-specific mortality rates recorded in Italy for person-years adequate for the enrolment period. The standardized mortality ratio (SMR) determined the relative risk of death over that of the age and sex matched general population. Results: Overall, 28/181 patients followed-up for a median period of 9.6 years (range 1–25 years) died. The 10 and 20-year overall survival rates for the whole series were 90.9% (95% CI, 84.3–94.8) and 62.9% (95% CI, 45.9–75.9), respectively. The number of expected deaths in the corresponding age and sex matched general population was 28.1, corresponding to a SMR = 1.00 (95% CI, 0.72–1.35), with an SMR for non-SVR patients of 3.85 (95% CI, 3.43–4.30), for untreated of 3.01 (95% CI, 2.64–3.42) and for decompensated of 6.70 (95% CI, 5.39–8.22). Conclusions: Patients with compensated HCV cirrhosis achieving SVR by IFN obtain a main benefit levelling their survival curve to that of the general population. Wider applicability of IFN-free regimens will possibly make this achievement more generalizable

Novel Staufen1 ribonucleoproteins prevent formation of stress granules but favour encapsidation of HIV-1 genomic RNA

Human immunodeficiency virus type 1 (HIV-1) Gag selects for and mediates genomic RNA (vRNA) encapsidation into progeny virus particles. The host protein, Staufen1 interacts directly with Gag and is found in ribonucleoprotein (RNP) complexes containing vRNA, which provides evidence that Staufen1 plays a role in vRNA selection and encapsidation. In this work, we show that Staufen1, vRNA and Gag are found in the same RNP complex. These cellular and viral factors also colocalize in cells and constitute novel Staufen1 RNPs (SHRNPs) whose assembly is strictly dependent on HIV-1 expression. SHRNPs are distinct from stress granules and processing bodies, are preferentially formed during oxidative stress and are found to be in equilibrium with translating polysomes. Moreover, SHRNPs are stable, and the association between Staufen1 and vRNA was found to be evident in these and other types of RNPs. We demonstrate that following Staufen1 depletion, apparent supraphysiologic-sized SHRNP foci are formed in the cytoplasm and in which Gag, vRNA and the residual Staufen1 accumulate. The depletion of Staufen1 resulted in reduced Gag levels and deregulated the assembly of newly synthesized virions, which were found to contain several-fold increases in vRNA, Staufen1 and other cellular proteins. This work provides new evidence that Staufen1-containing HIV-1 RNPs preferentially form over other cellular silencing foci and are involved in assembly, localization and encapsidation of vRNA.Fil: Abrahamyan, Levon G.. Davis Jewish General Hospital; CanadáFil: Chatel Chaix, Laurent. Davis Jewish General Hospital; CanadáFil: Ajamian, Lara. Mc Gill University; Canadá. Davis Jewish General Hospital; CanadáFil: Milev, Miroslav P.. Mc Gill University; Canadá. Davis Jewish General Hospital; CanadáFil: Monette, Anne. Mc Gill University; Canadá. Davis Jewish General Hospital; CanadáFil: Clément, Jean François. Davis Jewish General Hospital; CanadáFil: Song, Rujun. Mc Gill University; Canadá. Davis Jewish General Hospital; CanadáFil: Lehmann, Martin. Davis Jewish General Hospital; CanadáFil: DesGroseillers, Luc. University Of Montreal; CanadáFil: Laughrea, Michael. Mc Gill University; Canadá. Davis Jewish General Hospital; CanadáFil: Boccaccio, Graciela Lidia. Fundación Instituto Leloir; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquimicas de Buenos Aires; ArgentinaFil: Mouland, Andrew J.. Mc Gill University; Canadá. Davis Jewish General Hospital; Canad