Search results for " STRESS"

The Influence of the COVID‑19 Pandemic Emergency on Alcohol Use: A Focus on a Cohort of Sicilian Workers

2023

The period between the beginning and the end of the COVID-19 pandemic emergency generated a general state of stress, affecting both the mental state and physical well-being of the general population. Stress is the body’s reaction to events or stimuli perceived as potentially harmful or distressing. Particularly when prolonged over time, it can promote the consumption of different psychotropic substances such as alcohol, and thus the genesis of various pathologies. Therefore, our research aimed to evaluate the differences in alcohol consumption in a cohort of 640 video workers who carried out activities in smart working, subjects particularly exposed to stressful situations due to the string…

Autonomy and Relatedness in Mother-adolescent Relationship and Parenting Stress.

2008

Genetic Engineering Strategies for Abiotic Stress Tolerance in Plants

2015

Crop plants are affected by a variety of abiotic stresses such as salinity, drought, extreme temperatures, and oxidative stress and cause a significant yield loss (more than 50 %). In the near future, these abiotic stresses might increase because of global climate change. Abiotic stresses lead to dehydration or osmotic stress through reduced availability of water for vital cellular functions and maintenance of turgor pressure and also result in high production of reactive oxygen species (ROS). Plants are evolved with various mechanisms such as changes in cellular and metabolic processes to cope with the stress condition. Recent developments in molecular genetics have contributed greatly to …

Modelling temperature-dependent dynamics of single and mixed infections in a plant virus

2022

Multiple viral infection is an important issue in health and agriculture with strong impacts on society and the economy. Several investigations have dealt with the population dynamics of viruses with different dynamic properties, focusing on strain competition during multiple infections and the effects on viruses’ hosts. Recent interest has been on how multiple infections respond to abiotic factors such as temperature (T). This is especially important in the case of plant pathogens, whose dynamics could be affected significantly by global warming. However, few mathematical models incorporate the effect of T on parasite fitness, especially in mixed infections. Here, we investigate simple mat…

Absorption kinetics and swelling stresses in hydrothermally aged epoxies investigated by photoelastic image analysis

2015

Abstract The present work proposes an experimental optical methodology able to measure the transient swelling stresses induced by the water uptake ageing of polymers. In particular, the work describes the implementation of a Photoelastic technique to quantify internal stresses arising during the hydrothermal ageing of cast epoxy samples. The material investigated is a model DGEBA/DDS epoxy system. Curing and post-curing cycles have been optimised in order to obtain a fully cured, high T g , and completely stress free initial condition. Rectangular beam samples were then left in a hydrothermal bath at 90 °C, and regularly monitored by gravimetric and photoelastic analyses. The quantitative e…

FREE RADICAL THEORY OF FRAILTY: MOLECULAR MECHANISMS OF FRAILTY RESULTING FROM OXIDATIVE STRESS

2018

The free radical theory of ageing provided an intellectual framework for many laboratories working on ageing. However, experimental and clinical evidence showing that high doses of antioxidants did not have an effect on ageing or on age-associated diseases, cast doubts on the validity of this theory. Data from our own laboratory showed that oxidative stress does not correlate with age, especially in the geriatric population, but rather with the frailty state. This has led us to postulate the free radical theory of frailty in which frailty is associated with oxidative stress, but age itself is not. Superoxide dismutase deficient mice are more frail than controls. But more importantly, we obs…

Putrescine accumulation in Arabidopsis thaliana transgenic lines enhances tolerance to dehydration and freezing stress

2011

Polyamines have been globally associated to plant responses to abiotic stress. Particularly, putrescine has been related to a better response to cold and dehydration stresses. It is known that this polyamine is involved in cold tolerance, since Arabidopsis thaliana plants mutated in the key enzyme responsible for putrescine synthesis (arginine decarboxilase, ADC; EC 4.1.1.19) are more sensitive than the wild type to this stress. Although it is speculated that the over-expression of ADC genes may confer tolerance, this is hampered by pleiotropic effects arising from the constitutive expression of enzymes from the polyamine metabolism. Here, we present our work using A. thaliana transgenic pl…

Effect of Multiple Stressors on marine organism predicted and quantified through bioenergetic mechanistic models

Anthropogenic pressure on coastal ecosystems is vast and diverse, simultaneous impacts such as pollution, eutrophication and fishing pressure nowadays add up and interact with the effects of climate change (e.g., global warming, acidification and sea level rise). The magnitude of these effects on marine species and their replies can vary and the possible changes can depend on: i) species life-histories (LH) traits, ii) local environmental conditions and iii) contextual presence of more than one anthropogenic related stressor. The study of a single anthropogenic disturbance or Climate Change-derived alteration on multi-level ecological responses is misleading and generates unrealistic conclu…

Acoustic doppler velocity profiler for velocity and turbulence measurements in a large amplitude meandering flume

2008

Flow over deformed bed of a meandering laboratory channel is experimentally investigated. The velocity components have been obtained using an Ultrasonic Doppler Profiler (DOP2000) that measures the instantaneous flow velocity profile along the probe direction. In this work, some results obtained in peculiar sections along the channel are reported. A refined mesh of the measurement points has been used for each considered cross-section. The analysis of the collected data essentially confirms that when the aspect ratio is small the secondary circulation assumes great importance and, in accordance with previous findings, a second counter-rotating secondary circulation cell appears near the fre…

Generalized effective stress concept for saturated active clays

2021

Experimental evidence shows that changes in pore-water chemistry can significantly affect the mechanical behavior of saturated active clays. Despite this evidence, how the chemical composition of the pore water can be considered in effective stress definition is questionable. This paper develops the concept of generalized effective stress for active clays. To this end, physicochemical studies on water–clay mineral interactions are used to clearly define the different types of ions and water present in an active clay. In particular, the presence of both movable and non-movable ions within the liquid water is highlighted. Taking this into account, thermodynamic and geochemistry principles ar…