Search results for "fiber"
showing 10 items of 2343 documents
Single-mode Bragg gratings in tapered few-modes and multimode fibers
2019
We propose the implementation of fiber Bragg gratings in tapered few-mode and multimode fibers to accomplish single-mode operation by reducing the core diameter, while preserving the core-cladding structure. The gratings present a single reflection band, and the device shows low insertion losses after the taper fabrication and the fiber Bragg gratings inscription. The excitation of high-order odd modes in the core of the fiber has been identified as the main loss mechanism; it can be prevented by means of symmetric illumination of the fibers. We also demonstrate the excitation of high-order cladding modes (cladding-air modes) along the taper transitions; these modes can be removed without a…
Osteogenic differentiation of periodontal fibroblasts is dependent on the strength of mechanical strain
2012
Abstract Objective During orthodontic therapy the correct strength of mechanical strain plays a key role for bone remodelling during tooth movement. Aim of this study was to investigate the osteogenic differentiation of human periodontal ligament fibroblasts (HPdLF) depending on the applied strength of mechanical strain compared to osteoblasts (HOB). Design HPdLF and HOB were loaded with different strengths (1%, 5% and 10%) of static mechanical strain (SMS) for 12 h in vitro. Viability was verified by MTT and apoptosis by TUNEL assay. Gene expression of cyclin D1, collagen type-1 (COL-I), alkaline phosphatase (ALP), osteocalcin, osteoprotegerin (OPG) and receptor activator of the NF-κB liga…
Le Fratture di Rotula
2015
Patellar fractures are relatively uncommon, accounting for approximately 1% of all fractures. Non-operative treatment represents the best choice for undisplaced patellar fractures. However, surgery becomes necessary when fractures are displaced by more than 2 mm, and may include open reduction and internal fixation. Accurate reduction and rigid fixation are required in order to allow early knee mobilization and to obtain a better clinical outcome. Several techniques have been described for patellar fracture fixation, such as tension band wiring, interfragmentary screw fixation, and the combination of screw fixation and cerclage. In this article up-to-date diagnosis, classification and treat…
Glucocorticoid-sensitive hereditary inclusion body myositis.
1996
We report a hereditary muscle disorder with features of inclusion body myositis (IBM) in two adult sisters with slowly progressive asymmetrical muscle weakness. The findings of light microscopic and ultrastructural investigations of muscle biopsy specimens were consistent with a diagnosis of IBM. Both patients improved and stabilized on immunosuppressive treatment with corticosteroids and azathioprine. This differentiates our patients from other sporadic and familial cases of IBM. Clinical and histological features are described and compared with those of other previously reported families with IBM.
Numerical experimental analysis of hybrid double lap aluminum-CFRP joints
2015
Abstract Due to their reliability and ease of assembly, both the adhesively bonded and the mechanical joints are commonly used in different fields of modern industrial design and manufacturing, to joint composite materials or composites with metals. As it is well known, adhesively bonded joints are characterized by high stiffness and good fatigue life, although delamination phenomena localized near the free edges may limit their use, especially for applications where corrosive environments and/or moisture can lead to premature failure of the bonding. In these cases, a possible alternative is given by the well-known mechanical joints. On the contrary, these last joints (bolted, riveted) requ…
MUSCLE BIOENERGETIC ABNORMALITY IN MYOTONIC-DYSTROPHY - A SECONDARY MITOCHONDRIAL DISORDER
1993
International audience; Abstract: The thenar muscles and gastrocnemius of a patient with myotonic dystrophy were investigated, at rest, by phosphorus nuclear magnetic resonance spectroscopy. A decrease in phosphocreatine level and an increase in inorganic phosphate and phosphodiester levels were found in the gastrocnemius, which was clinically spared, whilst the thenar muscles, which were wasted and affected by myotonia, exhibited only an increased inorganic phosphate level and an elevated pH. These findings were comparable with those found in other muscular disorders, such as Duchenne's and Becker's dystrophies, as well as in limb girdle dystrophy. They suggested that the abnormalities obs…
Immune-mediated rippling muscle disease with myasthenia gravis: a report of seven patients with long-term follow-up in two.
2009
We report seven patients with immune-mediated rippling muscle disease (iRMD) and AChR-antibody positive myasthenia gravis (MG) without germline caveolin-3 gene mutations. We describe the follow-up of two patients and the clinical features of five new patients (1 female, 4 male, aged 32 to 69 years). These presented with significant generalized, exercise-induced and electrically-silent muscle rippling with myalgia, combined with generalized MG. In two of the seven patients, MG appeared before iRMD. Mediastinal imaging excluded thymic alterations in all, although two had other coincident tumours. Myalgia and rippling were aggravated by acetylcholinesterase-inhibitor treatment. Generalized MG …
The pain threshold of high-threshold mechanosensitive receptors subsequent to maximal eccentric exercise is a potential marker in the prediction of D…
2017
Background Delayed-onset muscle soreness (DOMS) refers to dull pain and discomfort in people after participating in exercise, sport or recreational physical activities. The aim of this study was to detect underlying mechanical thresholds in an experimental model of DOMS. Methods Randomised study to detect mechanical pain thresholds in a randomised order following experimentally induced DOMS of the non-dominant arm in healthy participants. Main outcome was the detection of the pressure pain threshold (PPT), secondary thresholds included mechanical detection (MDT) and pain thresholds (MPT), pain intensity, pain perceptions and the maximum isometric voluntary force (MIVF). Results Twenty volun…
Optoelectronic devices based on caesium lead halide perovskite nanocrystals
2020
Tradicionalmente, la implementación de materiales activos en circuitos fotónicos integrados se ha basado en la utilización de semiconductores III-V y vidrios y materiales ferroeléctricos dopados con iones de tierras raras. Sin embargo, en la actualidad existe una alternativa basada en (nano) materiales sintetizados por técnicas de química coloidal. La posibilidad de procesar nanomateriales en solución permite fabricar semiconductores con propiedades ópticas (emisión, absorción, dispersión de luz) que pueden diseñarse durante la síntesis. Además, su naturaleza coloidal permite integrarlas en cualquier arquitectura óptica mediante sencillas técnicas de impresión en tinta. En este contexto, lo…
Comparison of acute and chronic exercise effects in the lipid droplets topography skeletal muscle, following high and low-fat diet in mice
2015
In the modern world, diet patterns high on lipids, sedentary lifestyle and obesity contribute all in the development of metabolic syndrome, which in turn can lead to type 2 diabetes. All the excess fats, that the majority of the population consumes nowadays, are stored as ectopic fat, particularly in the skeletal muscle, a tissue beyond doubt insulin-sensitive. Physical activity has been proposed according to various studies to be the most drastic factor, which can induce changes in skeletal muscle lipid metabolism,as well as different diet models. We hypothesized that different exercise patterns and diet-changes can alter the spatial arrangement in lipid droplets (LDs) in different skeleta…