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Highlights • Considering the dependency of the eddy current loss on peak induction in the transformer model. • Studying the impact of considering the eddy current in the lamination on ferroresonance mode at critical points. • Investigate the stability of ferroresonance modes regarding the initial switching time. • The experimental validation of the simulation results. Abstract The susceptibility of ferroresonance to the eddy current in the iron core is presented in this paper. The stability of ferroresonance modes is investigated regarding to the eddy current in the core lamination. The impact of switching time on ferroresonance oscillations was done via a basin of attraction by identifying the initial points that can be encountered during transformer operation. An accurate dynamic model of transformer was implemented taking into account the dependence of frequency and peak induction. The experimental results are predicted using the implemented model with and without taking the effect of eddy current in the lamination. The comparison was made between the experimental results and the computed ones. It shows the necessity of considering the dependency of the iron losses on peak induction for an accurate predicting of ferroresonance behaviour at critical points. [ABSTRACT FROM AUTHOR]

Abstract This paper aims the investigation of the damage monitoring by the piezoresistive effect of the tufting threads in the sandwich structures. This novelty is an additional advantage besides the primary interest for inserting tufts in composite structures that concerns the improvement in the interlaminar fracture toughness. Tufting process reinforced through-thickness the polystyrene foam core and glass fiber sheets. Electrical measurements monitored the specimens through the tufted carbon threads during flatwise compression and low-velocity impact tests for evaluating the strain-sensing and damage response. The irreversible resistance change and infrared thermography (IRT) methods analyzed the damage extent in the tufts after impact tests. IRT characterized the damages from the concentration of temperature on the deteriorated regions of the tufts while injecting electrical current. These results were validated by the ultrasonic C-Scan maps that displayed the major damages in the same zone found on IRT technique. The present study validates the capability of the approach to monitoring strain and damage events by the tufts when subjected to compressive loading. The method also presents efficient to monitor the loading and damage detection, by the irreversible resistance change, under impact tests. [ABSTRACT FROM AUTHOR]

Abstract The present paper investigates the damage monitoring using the piezoresistive effect on the glass fiber-reinforced polymer (GFRP) omega stringers reinforced through-the-thickness by tufting. The experiments consisted of the electric resistance measurements from the tufted yarns during the pull-off tests on omega stringers. Acoustic emission (AE) and digital image correlation (DIC) techniques were also performed throughout the tests in order to evaluate the acoustic activity and the strain field respectively. Furthermore, non-supervised AE clustering was carried out and aided to determine the main damage events. The results presented that electric resistance measurements are in good correlation with the AE clusters, especially with those related to the delamination and tuft yarns fracture. Besides, these damage events are well distinguished from the electric resistance data. Also, DIC images exhibited that electric resistance is sensitive to local strain field as expected to piezoresistivity measurements. Therefore, tufting reinforcements have shown to be an interesting monitor of the structural health in real time, further their well-known ability to increase the mechanical out-of-plane properties of laminate composites. [ABSTRACT FROM AUTHOR]

The effect of trough-the-thickness reinforcement by tufting on impact and after impact behavior of woven carbon fiber composites is investigated. The density and angle of the carbon fiber threads during tufting process were varied to achieve better results on damage tolerance. The samples were submitted to out-of-plane impact with two different energies to compare their response under loading. Then, they were analyzed by ultrasonic C-Scan technique in order to evaluate the damaged zone. Further, compression after impact (CAI) assisted by acoustic emission and Digital Image Correlation compared the compressive strength and materials response according to their tufting parameters. Also, compression before impact (CBI) were performed to evaluate the in-plane properties of the tufted composites. The transversal tufting reinforcement achieved the best results when compared to angular and non-tufted laminate composites. Moreover, when increasing the tufting density, the damaged area is decreased and the ultimate compressive strength improved. Tufting reinforcements were found to decrease the damage area up to 4 times (transversal tufting) when compared to non-tufted laminates. Additionally, the residual ratio (CAI/CBI) increased up to 30% and 28% for the transversal and angular reinforcements respectively in comparison to the reference. [ABSTRACT FROM AUTHOR]

T-joints stiffeners made from carbon/epoxy composites have been increasingly applied in aeronautical structures, however as majority of the carbon fiber reinforced structures, they have faced with delamination problems. Through-the-thickness reinforcements for laminate composites have been studied as manner to increase transversal strength, especially reducing delamination. In the present work, carbon/epoxy T-joints reinforced transversally by one side stitching (OSS) and molded on Resin Transfer Molding (RTM) process have been performed as well as the reference (unstitched T-joints). The stitching position were designed after analysis of the unstitched T-joints by means of strain field on Digital Image Correlation (DIC) under pull-off test to better improve the areas submitted to large strain. Also, the stitched samples were mechanically tested in pull-off mode and were analyzed during tests by in situ microscopy and post-failure on Scanning Electron Microscopy .The energy release was better contained in the stitched structures especially in the critical region (delta-fillet), due to crack bridging that improved the delamination toughness. Otherwise, the stitch pattern generated by OSS process changed the strain fields asymmetrically when analyzed on DIC during tests. The stitched T-joints showed greater ultimate strength (25%) and load recovery post ultimate strength (19%) in comparison to the reference. [ABSTRACT FROM AUTHOR]

In the present study, we have investigated the effects of polyphenol-rich infusions from carob leaves and OFI-cladodes on inflammation associated with obesity and dextran sulfate sodium (DSS)-induced ulcerative colitis in Swiss mice. In vitro studies revealed that aqueous extracts of carob leaves and OFI-cladodes exhibited anti-inflammatory properties marked by the inhibition of IL-6, TNF-α and nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells concomitant with NF-κβ nucleus translocation inhibition. For in vivo investigations, Swiss male mice were subjected to control or high fat diet (HFD). At the 8th week after the start of study, animals received or not 1% infusion of either carob leaves or OFI-cladode for 4 weeks and were subjected to 2% DSS administration in drinking water over last 7 days. After sacrifice, pro-inflammatory cytokines levels in plasma and their mRNA expression in different organs were determined. Results showed that carob leaf and OFI-cladode infusions reduced inflammation severity associated with HFD-induced obesity and DSS-induced acute colitis indicated by decrease in pro-inflammatory cytokines expression (as such TNF-α, IL1b and IL-6) in colon, adipose tissue and spleen. In addition, plasma levels of IL-6 and TNF-α were also curtailed in response to infusions treatment. Thus, carob leaf and OFI-cladode infusions prevented intestinal permeability through the restoration of tight junction proteins (Zo1, occludins) and immune homeostasis. Hence, the anti-inflammatory effect of carob leaves and OFI-cladodes could be attributed to their polyphenols which might alleviate inflammation severity associated with obesity and colitis. [ABSTRACT FROM AUTHOR]

The aim of this study is to purpose a robust experimental method to measure both in-plane and out-of-plane shear moduli of a 3D woven Ceramic Matrix Composites (CMC) SiC-SiBC, using torsion tests on rectangular bars. To construct this methodology, several data reduction process have been discussed. Then, the edge effects and their consequences on the shear moduli values have been investigated, using a Finite Element Analysis. Based on the findings of this preliminary study, a robust experimental methodology has been developed. Its originality stems on the use of 3D Digital Image Correlation (DIC) to measure properly twist angle on a restricted area, where the edge effects have lower influence. This methodology has been first validated by proceeding torsion tests on Aluminum bars with well known isotropic properties. Then, the experimental method has been extended to a 3D woven CMC SiC-SiBC material, to measure both its in-plane and out-of-plane shear moduli. [ABSTRACT FROM AUTHOR]

Chemoprevention of Colorectal cancer (CRC) is the major concern for improving public health. We investigated the protective effects of carob, Ceratonia siliqua L., leaf polyphenols (CLP) against CRC. Phenolic content analysis showed that CLP is enriched with gallic acid and m-coumaric acid. We observed that CLP exerted a dose dependent cytotoxic effect through the induction of apoptosis on CRC cell lines, with an IC50 around 20 μg/mL. CLP induced intrinsic apoptotic pathway through the caspase-9 activation and PARP cleavage in HCT-116 and CT-26 cells. Moreover, CLP induced cell cycle arrest in the G1 phase through p53 activation. Gallic acid and m-coumaric acid exerted similar effect of CLP but at higher concentration to that expected to be present in CLP, suggesting the synergistic effect between polyphenols in CLP activity. Interestingly, the carob leaf infusion reduced CT-26 tumour growth in BALB/c mice. This study suggests that CLP can be used for the prevention of CRC. [ABSTRACT FROM AUTHOR]

Large area, time resolved, in-situ optical scanning of constant displacement (four-point bend) tests has been used to monitor the environmentally assisted cracking (EAC) initiation and crack growth behaviour of AA7085 and AA7449 T7651 thick plate materials, exposed to warm-humid air (50 % RH & 70 °C). Subsequent fractography has revealed the dominant initiation sites originating at surface connected gas pore clusters, in combination with reactive Mg-containing constituent intermetallic compounds co-located on grain boundaries. Cracks were also shown to grow at stress intensities substantially below the K IEAC threshold measured via DCB testing, which should not therefore be taken as a limit below which EAC cannot occur. • In-situ optical monitoring was utilised to accurately identify EAC crack initiation sites in 7xxx aluminium alloys in humid air. • High-resolution fractography found that cracks initiated at surface connected gas pores, sometimes in combination with Mg-rich IMC particles. • Short cracks exhibited highly variable growth rates, reflecting the susceptibility of short crack growth to variation in local microstructure. • Naturally nucleated short cracks can grow at stress intensities substantially below the K IEAC threshold, as measured from DCB tests. [ABSTRACT FROM AUTHOR]

Turner syndrome (TS) is the most common genetic disorder occurring in 1/2500 live-born girls. Morbimortality is increased in TS and related to cardiovascular (CV) disease such as congenital heart disease (CHD), aortic dilatation and dissection. The main objective of this study was the evaluation of the cardiovascular risk of aortic dissection in pediatric and young patients with TS. A prospective multicentric study was conducted in young female with a Karyotype proven TS. Physical examination and echocardiography were performed for all the patients. Ambulatory monitoring of blood pressure of 24 h for patients over 6 years of age, cardiac MRI or CT-scan for patients over 10 years of age or as needed. In total, 173 patients were included; mean age was 10.5 years. A total of 61.3% had mosaic, 29.5% had monosomy and 9.2% had a structural X chromosome abnormality. The frequency of congenital heart disease was 31.2%. Bicuspid aortic valve was the most common being detected in 22.5% followed by aortic coarctation (4.6%). High blood pressure was detected in 26 patients (15%) with 41.7% of non-dipper profile. Primary hypertension was the most common. Aortic dilatation was found in 4 cases, neither aneurysm nor dissection were found 69.4% of patients were at mild risk of dissection, 28.3% were at moderate risk and 2.3% were at severe risk. BAV, coarctation and monosomy appeared to be risk factors of aortic vasculopathy. A cardiovascular profile should be determined at diagnosis and patient should have a careful monitoring from the age of diagnosis to adulthood in order to identify the patient at risk of aortic dissection and prevent CV complications. [ABSTRACT FROM AUTHOR]

Improvement of the interfacial toughness of composite sandwich by stitching process is studied in this paper. Double cantilever beam tests are performed to quantify the influence of the presence of the through-the-thickness reinforcement on the skin–core interfacial toughness. The compliance method is used to determine the energy release rate but with a specific formula where an exponential fitting is preferred instead of the power classical fitting. The failure mechanisms for energy absorption are observed and experimental crack travel through the stitches gives an explanation of the particular evolution of the loading curve. An analytical approach is also proposed to predict the overall behavior of the interface. The classical theory of crack propagation is adapted in order to consider the lack of symmetry of the test as the crack does not propagate in the middle of the specimen and to consider additional plate device strengthen the brittle skin of the sandwich. The result of the model is satisfying for the unstitched structure and the range of the predicted critical energy release rate is in accordance with the experimental result. Regarding stitched sandwich, the limits of the model is highlight due to the theory that does not take into account the transverse reinforcement. [ABSTRACT FROM AUTHOR]

Highlights: [•] Statistics of Discrete Fourier Transform. [•] Five features are chosen to represent plate signal. [•] Bayesian approach is used to classify the plate region from other regions. [•] The method achieves classification rate of 97.27%. [•] Comparison analysis is provided. [Copyright &y& Elsevier]

New generation (new-gen) 7xxx series alloys have recently been shown to have higher susceptibility to environmental assisted cracking (EAC) in humid air, compared to AA7050, in T7651 tempers. Hydrogen (H)-EAC fracture features of brittle intergranular (IG) and transgranular (TG) fracture modes were observed with humidity levels as low as 20%. Initiation was favoured at sites of intermetallic particle clusters with gas pores. The higher performance of AA7050 was attributed to the difficulty of initiation in this alloy, where the grain structure, combined with an intrinsic resistance of the grain boundaries to IG-EAC, made the attainment of sustained cracking difficult. [Display omitted] • Strain rates as low as 10-8 s-1 were utilised to assess the EAC performance of aluminium alloy 7xxx series in humid air. • The complete sequence of EAC was presented through high-resolution fractography of well-preserved fracture surfaces. • Thick plate AA 7085 and AA 7449 were more susceptible to EAC in humid air compared to AA7050 in their T7651 tempers. • AA7050 high resistance to EAC in humid air was attributed to the difficulty of growing short cracks during EAC initiation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Role played by implied volatility on the WTI crude oil price. [•] Inverse leverage effect is dominant in WTI prices. [•] Existence of regular and inverted feedback effects. [•] Fear of oil consumers to face rising oil prices. [•] Hedging strategies for traders, risk- and fund-managers. [Copyright &y& Elsevier]

Abstract: This article provides an improvement of the technology of through-the-thickness reinforcement of thermosetting composite sandwiches by the insertion of stitching yarns. The aim of this work is to propose a model that would lead to the representation of the tri-dimensional elastic and ultimate performances of these 3D structures under out-of-plane shearing and compressive stress. To reach that goal, an analytical approach is proposed without the contribution of the numerical finite element technique. From experimental observations, this complex structure can be considered as a simple lattice made up of the stitches treated as bars composed of the UD impregnated yarns. The transverse compression and the out-of-plane shear module can be determined from the geometrical parameters of the structure. Moreover, the ultimate stress can be approximated once the cinematic of the failure of the structure has been experimentally identified for each stress case. Finally, the buckling of stitches ends up in the ruin of the material in each case. Thus, a classical theory of buckling can be used and a particular work has been done on the representation of the anchorage point of the stitches on the skin. The final model which is endowed with a good sensitivity enables us to predict the ultimate values in both loading cases. Finally, the variation of stitching angle allows to virtually optimize the material used according to the external loading. [Copyright &y& Elsevier]

Abstract: Saethre–Chotzen syndrome is a craniosynostosis syndrome that is rarely diagnosed prenatally. It is caused by cytogenetic deletions or mutations of the TWIST1 gene. We report here a de novo prenatal case with clinically and molecularly well defined Saethre–Chotzen syndrome due to a TWIST1 deletion. This is the first reported case of a deletion encompassing the TWIST1 gene to be diagnosed prenatally. We recommend screening for a deletion of the TWIST1 gene if signs of coronal craniosynostosis with no clear etiology are observed on ultrasound examination. [Copyright &y& Elsevier]

Abstract: After highlighting the improvement of the mechanical performances involved by transverse reinforcement implementation in previous several studies, the mechanical behavior of stitched sandwich structures is analytically approached in this paper. The final purpose of this work is a modeling of the elastic performances of these structures. To predict the in-plane behavior, the classical theory of sandwiches is adapted and used by treating the foam core strengthened by stitches as a homogenized volume. This approach leads to the creation of an orthotropic equivalent core material. Its elastic properties depend on each component and their volume participation. The comparison between simulated and experimental values is quite good. The main interest of the multi-scale approach concerns a predictive tool. Indeed, it becomes realistic to obtain the elastic properties of stitched sandwich according to the geometrical parameters of the stitches and the mechanical properties of the components. [Copyright &y& Elsevier]

Abstract: The paper aims at evaluating the damage resistance of sandwich structures composed of stitched foam core and glass facesheets subjected to low-velocity impact. To obtain a suitable baseline comparison, the equivalent set of properties was measured for an equivalent unstitched sandwich. Based on the force and energy histories, parameters have been introduced as following: load at incipient damage, maximum load, penetration depth at maximum load, total energy absorbed during impact and impact damage area. The impact resistance of the sandwich structure is greatly improved by the presence of the stitches. Skin/core delamination is limited and initial energy is used to degrade core’s stitches. Moreover the global behavior under impact is influenced by the stitching geometrical parameters. [Copyright &y& Elsevier]

Abstract: Paperboard exhibits a complex mechanical behaviour, which is governed by several phenomena. This work proposes a contribution to the identification of these phenomena. Uni-axial tensile tests under various configurations were carried out on the paperboard and corrugated cardboard. Observations under scanning electron microscopy were thereafter done in order to identify the microscopic phenomena produced in the structure. These observations made possible to highlight the presence of damage and its various appearance mechanisms. [Copyright &y& Elsevier]

Abstract: Corrugated cardboard is very sensitive to atmospheric conditions. The aim of this work is to study the effects of these parameters, in fact the relative humidity (RH), on the mechanical behaviour of a sandwich structure of the corrugated cardboard type. For that, tensile tests were used under various rates of relative humidity. In high rates of moisture, the instrumentation must be adapted. A preliminary comparison of several measurement methods of the mechanical properties was carried out. It made it possible to validate the method of strain measurement using the measurement of the displacement which requires a minimal handling of the specimen. During this study, the effect of the water content on the mechanical properties is presented. Moreover, the viscoelastic character coupled with the damage of this material is high lighted. [Copyright &y& Elsevier]

Abstract: Monolithic stitched composite materials successfully inspired the addition of transverse reinforcements in the case of sandwich structures. Indeed, the gains are undeniable in term of ultimate stress and of modulus regarding the principal mechanical tests practiced on sandwich (bending, shearing and compression). These bonds reduce the impact of the inter-laminar shearing which tends to break the connection between the core and the skins. Moreover, such reinforcements finally increase mechanical properties in the thickness direction, thus solving the principal disadvantage of these sandwich structures. Although the mass of such stitched panels is higher than that of the unstitched ones, the specific performances remain considerable. The direct influence of the macro-structural parameters of the stitches (step and angle) on the mechanical behavior of the structure is presented. It was also clearly highlighted that it is necessary to find a compromise between the structural parameters and the mass in order to obtain the expected mechanical performances. [Copyright &y& Elsevier]

Motivated by computed homogeneous of linear corrugated cardboard behavior, an analytical model related to the assessment of equals behavior is proposed. This model takes into account the geometrical and mechanical properties of the corrugated cardboard constituents. An experimental methodology is also proposed to obtain both the in-plane elastic properties of each constituents and the corrugated cardboard. After model validation by a comparison with the experiment results, a parametric study is conducted studying the effect of geometrical parameters on in-plane elastic properties. Moreover, in order to assess the relevance of the homogenization method, a finite element model for three-point bending test is created. Two approaches are adopted: the first one models separately the core and liner of the corrugated cardboard with thin shell element (3D approach), whereas the second approach being of particular interest in this work, considers the corrugated cardboard sandwich as a homogeneous plate and modeled therefore by a plate elements. It is shown that the simplified homogenized procedure is adequately accurate and 10 times faster than the 3D approach for effectively analyzing corrugated cardboard panel in the preliminary and optimum design stages. [Copyright &y& Elsevier]

The bone marrow karyotypes of three patients with acute myelocytic leukemia (AML) or myelodysplastic syndrome (MDS) were studied at diagnosis and revealed, multiple copies of the same chromosomal anomaly, considered as psu idic(21)(q22) associated with other rearrangement(s). The karyotype of a fourth patient with MDS in transformation showed one copy of a dicentric marker presumably derived from a similar psu idic(21) by (tandem?) interstitial amplification of part of its structure, resembling a “homogeneous staining region”, and described as der(21)psu idic(21)(q22)hsr(21)(q22). This rearrangement, previously described in isolated cases only, might be considered as recurrent in AML/MDS and associated with an unfavorable prognosis. It is most probably a secondary change, because it was never observed as sole abnormality and the main association, as for trisomy 21, was with del(5q). In the four cases, the number of partial supernumerary segmental 21pter→21q22 copies, ranged from 2 to 10. The AML1 gene did not appear to be the common target of this amplification because this locus had been lost by the psu idic(21) in one patient [Copyright &y& Elsevier]

The use of composite materials for structural applications requires the analysis of parameters such as the long-term behaviour in aggressive environments. The effects of accelerated ageing conditions on woven-fibre composite materials are analysed after an exposure from 1300 hours at 70 °C with 95% of relative humidity. The materials studied are two composites composed of glass-fibre reinforcement (twill and satin weaves) with two types of epoxy resin matrix. This paper aims to investigate the parameters of composite degradation under loading and ageing conditions and to understand damage events by means of techniques such as acoustic emissions and microscopic observations. [Copyright &y& Elsevier]

• Correlative NanoSIMS and SEM-EDX was used to identify deuterium localisation in nickel alloy 625+ (UNS N07716). • Local deuterium enrichments were detected at – dislocation slip bands, twin boundary and GB σ phase. • Deuterium mapping analysis highlighted the synergistic role of deformation and deuterium transport during HE cracking. Hydrogen induced cracking behaviour of O&G nickel alloy 625+ (UNS N07716) was investigated. Deuterium was introduced electrochemically into samples by cathodic polarisation (3.5 wt.% NaCl.D 2 O) under different mechanical conditions. Subsequently, deuterium distributions were mapped using NanoSIMS. Deuterium was used as an isotopic tracer instead of hydrogen to avoid the detection of hydrogen artefacts. Complimentary image analysis using scanning electron microscopy (SEM) and low voltage energy dispersive X-ray (EDX) allowed the identification of microstructural features corresponding to deuterium enrichments. The results provided experimental evidence of enrichments at dislocation slip bands (DSB), twin boundary and grain boundary features that include σ precipitates. [ABSTRACT FROM AUTHOR]

This study focuses on the experimental identification of the first damage envelope in a 3D woven composite with polymer matrix, under multi-axial loadings including combined in-plane tension and out-of-plane shear loadings (σ-τ envelopes). Proportional Tensile-Torsion tests on rectangular bars were performed to induce different multi-axial stress states. To enable envelopes identification, onset of the first damage has been evaluated thanks to the correlation of various and complementary investigation measurement techniques, such as Stereo-Digital Image Correlation (Stereo-DIC), Acoustic Emission (AE) and in-situ microscopic observations. In addition, a specific data reduction process has been used to manage accurate quantification of the stress state induced by the multi-axial loadings. Based on these findings, both σ 11 -τ 13 and σ 22 -τ 23 envelopes were identified on a 3D woven composite material with polymer matrix. Using microscopic observations, damage mechanisms (type and localization) related to the multi-axial loadings were identified. In addition, thanks to the strain fields measured by the Stereo-DIC on the material surface, particular relations between the multi-axial loadings and the 3D woven architecture have been established. [ABSTRACT FROM AUTHOR]