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In this paper, the effect of different values of load frequency on the evolution of the stress versus number of cycles to failure curve for a graphite-epoxy composite is studied. Two types of materials have been considered: unidirectional tape and woven fabric laminates. Fatigue tension-tension tests at different orientation angles and several frequency values have been carried out. The results show there is almost no effect of the load frequency in the S-N curve of unidirectional laminates. For woven fabric laminates, only under off-axis tension, the effect of frequency becomes a remarkable parameter in the fatigue behavior. [ABSTRACT FROM AUTHOR]

We propose an extension of parametric active contours designed to track nonoccluding objects transiently touching each other, a task where both parametric and single level set-based methods usually fail. Our technique minimizes a cost functional that depends on all contours simultaneously and includes a penalty for contour overlaps. This scheme allows us to take advantage of known constraints on object topology, namely, that objects cannot merge. The coupled contours preserve the identity of previously isolated objects during and after a contact event, thus allowing segmentation and tracking to proceed as desired. [ABSTRACT FROM AUTHOR]

Background and purpose: For over 20 years, as a group we have been using flunarizine in primary headache disorders. Flunarizine is widely used in Europe, but not licensed in the UK. In September 2014, the National Institute for Clinical Excellence published supportive guidelines for flunarizine use in migraine, based on randomized controlled evidence that it is as effective as propranolol and topiramate in adults. Methods: We reviewed a cohort of adult patients (n = 200) treated with flunarizine from our practice. The clinical information of these patients, i.e. diagnosis, dose, efficacy, side effects and duration of treatment, was collected. Results: The most common indication for flunarizine use was chronic migraine, followed by migraine with aura, sporadic hemiplegic migraine, familial hemiplegic migraine and new daily persistent headache with migrainous features. Flunarizine was generally effective, with only 24% (n = 47) of patients reporting no clinical effect. The most common dose used was 10 mg per day. Duration of treatment information was available for 39% (n = 78) of patients. Of these patients, 64% (n = 50) continued treatment for more than 1 year. Doses up to 15 mg were generally well tolerated, with only 10.5% (n = 21) of patients stopping treatment due to adverse effects. The most common adverse events were tiredness, mood change and weight gain. Conclusion: The data provide supportive evidence from tertiary headache practice in the UK for the use of flunarizine in migraine. The data encourages development of future guidance regarding flunarizine use in headache centres in countries where its use is not routine. [ABSTRACT FROM AUTHOR]

We propose a structured illumination microscopy method to combine super resolution and optical sectioning in three-dimensional (3D) samples that allows the use of two-dimensional (2D) data processing. Indeed, obtaining super-resolution images of thick samples is a difficult task if low spatial frequencies are present in the in-focus section of the sample, as these frequencies have to be distinguished from the out-of-focus background. A rigorous treatment would require a 3D reconstruction of the whole sample using a 3D point spread function and a 3D stack of structured illumination data. The number of raw images required, 15 per optical section in this case, limits the rate at which high-resolution images can be obtained. We show that by a succession of two different treatments of structured illumination data we can estimate the contrast of the illumination pattern and remove the out-of-focus content from the raw images. After this cleaning step, we can obtain super-resolution images of optical sections in thick samples using a two-beam harmonic illumination pattern and a limited number of raw images. This two-step processing makes it possible to obtain super resolved optical sections in thick samples as fast as if the sample was two-dimensional. [ABSTRACT FROM AUTHOR]

An imbalance between inhibitory and excitatory neurotransmission has been proposed to contribute to altered brain function in individuals with Down syndrome (DS). Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system and accordingly treatment with GABA-A antagonists can efficiently restore cognitive functions of Ts65Dn mice, a genetic model for DS. However, GABA-A antagonists are also convulsant which preclude their use for therapeutic intervention in DS individuals. Here, we have evaluated safer strategies to release GABAergic inhibition using a GABA-A-benzodiazepine receptor inverse agonist selective for the α5-subtype (α5IA). We demonstrate that α5IA restores learning and memory functions of Ts65Dn mice in the novel-object recognition and in the Morris water maze tasks. Furthermore, we show that following behavioural stimulation, α5IA enhances learning-evoked immediate early gene products in specific brain regions involved in cognition. Importantly, acute and chronic treatments with α5IA do not induce any convulsant or anxiogenic effects that are associated with GABA-A antagonists or non-selective inverse agonists of the GABA-A-benzodiazepine receptors. Finally, chronic treatment with α5IA did not induce histological alterations in the brain, liver and kidney of mice. Our results suggest that non-convulsant α5-selective GABA-A inverse agonists could improve learning and memory deficits in DS individuals. [ABSTRACT FROM AUTHOR]

An imbalance between inhibitory and excitatory neurotransmission has been proposed to contribute to altered brain function in individuals with Down syndrome (DS). Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system and accordingly treatment with GABA-A antagonists can efficiently restore cognitive functions of Ts65Dn mice, a genetic model for DS. However, GABA-A antagonists are also convulsant which preclude their use for therapeutic intervention in DS individuals. Here, we have evaluated safer strategies to release GABAergic inhibition using a GABA-A-benzodiazepine receptor inverse agonist selective for the α5-subtype (α5IA). We demonstrate that α5IA restores learning and memory functions of Ts65Dn mice in the novel-object recognition and in the Morris water maze tasks. Furthermore, we show that following behavioural stimulation, α5IA enhances learning-evoked immediate early gene products in specific brain regions involved in cognition. Importantly, acute and chronic treatments with α5IA do not induce any convulsant or anxiogenic effects that are associated with GABA-A antagonists or non-selective inverse agonists of the GABA-A-benzodiazepine receptors. Finally, chronic treatment with α5IA did not induce histological alterations in the brain, liver and kidney of mice. Our results suggest that non-convulsant α5-selective GABA-A inverse agonists could improve learning and memory deficits in DS individuals. [ABSTRACT FROM PUBLISHER]

Abstract: Background: Renal interstitial fibrosis (IF), the main histopathologic feature of chronic allograft nephropathy (CAN), may be an important surrogate endpoint for patient follow-up. IF is currently assessed by semiquantitative analysis, but automatic color image analysis may be a more reliable, reproducible method to evaluate IF. We performed a retrospective analysis to calculate IF on routine renal biopsies 1 year after transplantation. Methods: Data were obtained from MO2ART, a prospective multicenter trial in which the cyclosporine microemulsion dose was adjusted based on C2 levels. We included 26 patients in whom routine renal biopsy at 1 year was available from two centers. For each biopsy, a section was analyzed by a program of color segmentation image that automatically extracted green-colored areas characteristic of IF. Results were expressed as percent IF and grade namely grade I, <25%; grade II, 25% to 50%; and grade III, >50%. The results were compared according to clinical and biological data. Results: The 26 patients had a mean IF score of 0.35 ± 0.04. We observed 34.6% CAN grade I; 46.1%, grade II; and 19.2%, grade III. Serum creatinine at 3 years was greater in the higher grade of automated IF by repeated ANOVA. Conclusion: Automatic quantification of IF on routine biopsy at 1 year after transplantation was predictive of renal outcome. This technique may provide an interesting tool for the early diagnosis of CAN after renal transplantation. [Copyright &y& Elsevier]