Damage of woven composite under tensile and shear stress using infrared thermography and micrographic cuts

Infrared thermography was used to study damage developing in woven fabrics. Two different experiments were performed, a ±45° tensile test and a rail shear test. These two different types of tests show different damage scenarios, even if the shear stress/strain curves are similar. The ±45° tension test shows matrix hardening and matrix cracking whereas the rail shear test shows only matrix hardening. The infrared thermography was used to perform an energy balance, which enabled the visualization of the portion of dissipated energy caused by matrix cracking. The results showed that when the resin is subjected to pure shear, a larger amount of energy is stored by the material, whereas when the resin is subjected to hydrostatic pressure, the main part of mechanical energy is dissipated as heat

Damage analysis and fracture toughness evaluation in a thin woven composite laminate under static tension using infrared thermography

This work deals with the issue of damage growth in thin woven composite laminates subjected to tensile loading. The conducted tensile tests were monitored on-line with an infrared camera, and tested specimens were analysed using Scanning Electron Microscopy (SEM). Combined with SEM micrographs, observation of heat source fields enabled us to assess the damage sequence. Transverse weft cracking was confirmed to be the main damage mode and fiber breakage was the final damage leading to failure. For cracks which induce little variation of specimen stiffness, the classic “Compliance method” could not be used to compute energy release rate. Hence, we present here a new procedure based on the estimation of heat source fields to calculate the energy release rate associated with transverse weft cracking. The results are then compared to those computed with a simple 3D inverse model of the heat diffusion problem and those presented in the literature

Examining a staging model for anorexia nervosa: empirical exploration of a four stage model of severity.

Background: An illness staging model for anorexia nervosa (AN) has received increasing attention, but assessing the merits of this concept is dependent on empirically examining a model in clinical samples. Building on preliminary findings regarding the reliability and validity of the Clinician Administered Staging Instrument for Anorexia Nervosa (CASIAN), the current study explores operationalising CASIAN severity scores into stages and assesses their relationship with other clinical features. Method: In women with DSM-IV-R AN and sub-threshold AN (all met AN criteria using DSM 5), receiver operating curve (ROC) analysis (n = 67) assessed the relationship between the sensitivity and specificity of each stage of the CASIAN. Thereafter chi-square and post-hoc adjusted residual analysis provided a preliminary assessment of the validity of the stages comparing the relationship between stage and treatment intensity and AN sub-types, and explored movement between stages after six months (Time 3) in a larger cohort (n = 171). Results: The CASIAN significantly distinguished between milder stages of illness (Stage 1 and 2) versus more severe stages of illness (Stages 3 and 4), and approached statistical significance in distinguishing each of the four stages from one other. CASIAN Stages were significantly associated with treatment modality and primary diagnosis, and CASIAN Stage at Time 1 was significantly associated with Stage at 6 month follow-up. Conclusions: Provisional support is provided for a staging model in AN. Larger studies with longer follow-up of cases are now needed to replicate and extend these findings and evaluate the overall utility of staging as well as optimal staging models

The depression influences the EDI scores in Anorexia Nervosa : a prospective follow-up study of 5-10 years.

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Outcome in AN adult patients: a 13-year follow-up in 484 patients.

International audienceBACKGROUND: To study the long-term prognosis of anorexia nervosa (AN), 484 adult AN patients were followed on a mean duration of 13 years. RESULTS: The mortality rate was 1.2%. Eight factors were linked to the lack of recovery at 2 years: low BMI at discharge, low energy and fat intakes, high drive for excessive exercising, high score for perfectionism, for interpersonal distrust and for anxiety, use of tube-feeding and adhesion to treatment (P18.5 kg/m(2); and having no physical hyperactivity. The recovery rate increased with the elapsing of relapse-free time (P=0.02). After a 13.5-year follow-up, 292 out of the 484 patients were recovered (60.3%), 25.8% had a relatively good outcome, 6.4% a bad outcome and 6.4% a severe outcome. Very few factors were identified as predictors of a good outcome (binge-eating/purging subtype, personality disorder)

Evaluation of washout using subtraction MRI for the diagnosis of hepatocellular carcinoma in cirrhotic patients with spontaneously T1-hyperintense nodules

Purpose: The purpose of this study was to assess the value of subtraction imaging on post-arterial phase images (i.e., portal venous, delayed/transitional and hepatobiliary phases) for the non-invasive diagnosis of hepatocellular carcinoma (HCC) in spontaneously hyperintense nodules on T1-weighted imaging in patients with cirrhosis. Materials and methods: Forty-five patients with a total 55 hepatic nodules that were spontaneously hyperintense on T1-weighted images were initially retrieved. All patients underwent MRI examination of the liver using extracellular agent. Each nodule was assessed for sensitivity and specificity using LI-RADS (Liver Imaging Reporting and Data System) during two reading sessions performed first without then with subtraction images on post-arterial phase images. The final standard of reference was defined by a step-by-step algorithm previously published combining histology, typical imaging, alfa fetoprotein and follow-up. Results: Forty-six nodules (26 HCC) in 39 patients with cirrhosis were analyzed. Using LI-RADS, the sensitivity and specificity for the diagnosis of HCC were 64% (95% CI: 41-83) and 67% (95% CI: 41-87) without subtraction; and 73% (95% CI: 50-89) (P > 0.999) and 33% (95% CI: 13-59) (P = 0.553) on subtraction imaging using extracellular contrast agent. Fifty-five percent (22/40) of nodules displayed a washout without subtraction and 70% (28/40) did so on subtraction imaging obtained with extracellular contrast agent. Twenty nodules out of 40 (50%) were classified LI-RADS 5 without subtraction, and 28 out of 40 nodules (70%) with subtraction. Conclusion: The results of this study suggest that the use of subtraction imaging on post-arterial phase images (i.e., PVP, DP/TP and HBP) is not relevant for the non-invasive diagnosis of HCC for spontaneously hyperintense nodules on T1-weighted images in patients with liver cirrhosis

Out-of-autoclave manufacturing of a stiffened thermoplastic carbon fibre PEEK panel

Out-of-Autoclave manufacturing methods, specifically Automated Tape Placement (ATP) and induction welding, used in the fabrication of a stiffened thermoplastic demonstrator panel, are presented in this study. The demonstrator panel consists of two stiffeners induction welded to a flat skin, to form a typical load bearing aerospace sub-component. The skin of the panel is manufactured from uni-directional Carbon Fibre (CF) Polyetheretherkeytone (PEEK) using laser assisted Automated Tape Placement (ATP) and the stiffeners are press formed from woven CF-PEEK. The stiffeners are fusion bonded to the skin using a continuous induction welding process. A susceptor material is used at the interface to ensure the required heating is concentrated at the weldline. Microscopy was used to examine the manufactured coupons for defects. Destructive testing was carried out to evaluate the strength of the overall assembly. The work shows that assemblies manufactured using continuous induction welding and ATP are suitable for load bearing aerospace applications

Overcoming Perfectionism: Protocol of a Randomized Controlled Trial of an Internet-Based Guided Self-Help Cognitive Behavioral Therapy Intervention

Background: Perfectionism is elevated across, and increases risk for, a range of psychological disorders as well as having a direct negative effect on day-to-day function. A growing body of evidence shows that cognitive behavioral therapy (CBT) reduces perfectionism and psychological disorders, with medium to large effect sizes. Given the increased desire for Web-based interventions to facilitate access to evidence-based therapy, Internet-based CBT self-help interventions for perfectionism have been designed. Existing Web-based interventions have not included personalized guidance which has been shown to improve outcome rates. Objective: To assess the efficacy of an Internet-based guided self-help CBT intervention for perfectionism at reducing symptoms of perfectionism and psychological disorders posttreatment and at 6-month follow-up. Methods: A randomized controlled trial method is employed, comparing the treatment arm (Internet-based guided self-help CBT) with a waiting list control group. Outcomes are examined at 3 time points, T1 (baseline), T2 (postintervention at 12 weeks), T3 (follow-up at 24 weeks). Participants will be recruited through universities, online platforms, and social media and if eligible will be randomized using an automatic randomizer. Results: Data will be analyzed to estimate the between group (intervention, control) effect on perfectionism, depression, and anxiety. Completer and intent-to-treat analyses will be conducted. Additional analysis will be conducted to investigate whether the number of modules completed is associated with change. Data collection should be finalized by December 2016, with submission of results for publication expected in mid-year 2017. Results will be reported in line with recommendations in the Consolidated Standards of Reporting Trials Statement for Randomized Controlled Trials of Electronic and Mobile Health Applications and Online TeleHealth (CONSORT-EHEALTH). Conclusions: Findings will contribute to the literature on treatment of perfectionism, the effect of treating perfectionism on depression and anxiety, and the efficacy of Internet-based guided self-help interventions. ClinicalTrial: ClinicalTrials.gov NCT02756871; https://clinicaltrials.gov/ct2/show/NCT02756871 (Archived by WebCite at http://www.webcitation.org/6lmIlSRAa