Search results for "STRESS"
showing 10 items of 6278 documents
Physiological stress responses ofAnguilla anguillato fenitrothion
1996
The present communication deals with the effect of fenitrothion (0.04 ppm) on the carbohydrate metabolism of the european eel Anguilla anguilla and its recovery from intoxication. Analysis of various parameters such as glycogen, lactate and glucose was made on different eel tissues after 2, 8, 12, 24, 32, 48, 56, 72 and 96 hr of fenitrothion exposure. Subsequently, the fish were allowed recovery periods of 8, 12, 24, 48, 72, 96, 144 and 192 hr in clean water, and the same parameters were evaluated. Muscle glycogen content decreased significantly during the exposure time, while blood glucose levels increased markedly. Gill, muscle and blood lactate values increased during pesticide exposure.…
Design characteristics, primary stability and risk of fracture of orthodontic mini-implants: Pilot scan electron microscope and mechanical studies
2013
Objectives: Orthodontic mini-implants (OMIs) are increasingly used in orthodontics but can fail for various reasons. This study investigates the effects of OMI design characteristics on the mechanical properties in artificial bone. Material and Methods: Twelve self-drilling OMIs (2 small, 6 medium, 4 large) from 8 manufacturers were tested for their primary stability in simulated medium-high cancellous bone and the risk to fracture in high-density methacrylate blocks. For the assessments of the maximum insertion torque (IT) and torsional fracture (TF) 5 of each OMI were used and for the pull-out strength (POS) 10. The OMIs were inserted with a torque screwdriver (12 sec/360°) until the bott…
Primary Stability of a Hybrid Self-Tapping Implant Compared to a Cylindrical Non-Self-Tapping Implant with Respect to Drilling Protocols in an Ex Viv…
2011
Background: Modifications of implant design have been intending to improve primary stability. However, little is known about investigation of a hybrid self-tapping implant on primary stability. Purposes: The aims of this study were to evaluate the primary stability of two hybrid self-tapping implants compared to one cylindrical non-self-tapping implant, and to elucidate the relevance of drilling protocols on primary stability in an ex vivo model. Materials and Methods: Two types of hybrid self-tapping implants (Straumann® Bone Level implant [BL], Straumann® Tapered Effect implant [TE]) and one type of cylindrical non-self-tapping implant (Straumann® Standard Plus implant [SP]) were investig…
Ex post-facto study of long-term stress in a sample of adoptees
2015
In this work we study the impact of relinquishment and the adoption process in posttraumatic symptoms and stressful life events in a group of 55 adults that were adopted as children after the Spanish Civil War (1936-1939). The effects of institutionalization, maltreatment and traumatic revelation of the adopted status have also been studied. No significant differences were found between institutionalized and non-institutionalized adoptees in posttraumatic symptomatology and stressful life events frequency. However, maltreated adoptees scored significantly higher in intrusion, arousal and stressful life events frequency than non-maltreated. Similar differences were found in the comparison be…
What are the ethical issues in relation to the role of the family in intensive care?
2017
International audience; A large proportion of patients admitted to the intensive care unit (ICU) are unable to express themselves, often due to acute illness, shock or trauma, and this precludes any communication and/or consent for care that might reflect their wishes and opinions. In such cases, the only solution for the ICU physician is to include the patient's family in the healthcare decisions. This can represent a significant burden on the family, on top of the psychological distress of the ICU environment and hospitalisation of their relatives, and many family members may suffer from anxiety, depression or symptoms of post-traumatic stress disorder (PTSD) during or after the hospitali…
Un élément fini mixte tridimensionnel pour le calcul des contraintes d'interface
1999
ABSTRACT In this paper we present an interfacial finite element designed for analysing planar interfaces in a three-dimensional approach. The element is derived from Hellinger-Reissner's mixed variational principle and takes into account the continuity of the displacement and of the transverse stress components through the interface. Stress analysis of a sandwich plate is made to assess the validity and the effectiveness of the element models, with comparisons to closed-form and numerical solutions.
Apparent interfacial shear strength of short-flax-fiber/starch acetate composites
2016
Abstract The paper deals with an indirect industry-friendly method for identification of the interfacial shear strength (IFSS) in a fully bio-based composite. The IFSS of flax fiber/starch acetate is evaluated by a modified Bowyer and Bader method based on an analysis of the stress–strain curve of a short-fiber-reinforced composite in tension. A shear lag model is developed for the tensile stress–strain response of short-fiber-reinforced composites allowing for an elastic-perfectly plastic stress transfer. Composites with different fiber volume fractions and a variable content of plasticizer have been analyzed. The apparent IFSS of flax/starch acetate is within the range of 5.5–20.5 MPa, de…
Depassivation Experiments by Laser‐Pulse‐Induced Spallation
1992
Depassivation experiments have been conducted by applying a technique developed for adhesion tests. A laser-pulse-induced spallation of the passive film is induced in situ without any contact between the laser beam and the passive film. The depassivation is controlled by the short pressures induced at the metal-film interface. The interfacial stresses at the metal-film interface could be studied by this technique
A Combination of Celecoxib and Glucosamine Sulfate Has Anti-Inflammatory and Chondroprotective Effects: Results from an In Vitro Study on Human Osteo…
2021
This study investigated the possible anti-inflammatory and chondroprotective effects of a combination of celecoxib and prescription-grade glucosamine sulfate (GS) in human osteoarthritic (OA) chondrocytes and their possible mechanism of action. Chondrocytes were treated with celecoxib (1.85 µM) and GS (9 µM), alone or in combination with IL-1β (10 ng/mL) and a specific nuclear factor (NF)-κB inhibitor (BAY-11-7082, 1 µM). Gene expression and release of some pro-inflammatory mediators, metalloproteinases (MMPs), and type II collagen (Col2a1) were evaluated by qRT-PCR and ELISA
A Thermodynamic Plasticity Formulation with Local and Nonlocal Internal Variables
2002
In order to obtain the elastic response of nonhomogeneous materials, it is often sufficient to adopt an implicit homogenization technique which allows one to treat the material as an equivalent continuum medium. For large stress concentration or for accurate small scale studies this widely applied technique may show some limit and a more refined analysis might be required involving nonlocal elastic effects, see e.g. Kroner (1967), Eringen et al. (1977).