Search results for " engineering"
showing 10 items of 38291 documents
Exploring fast proton transfer events associated with lateral proton diffusion on the surface of membranes
2019
Proton diffusion (PD) across biological membranes is a fundamental process in many biological systems, and much experimental and theoretical effort has been employed for deciphering it. Here, we report on a spectroscopic probe, which can be tightly tethered to the membrane, for following fast (nanosecond) proton transfer events on the surface of membranes. Our probe is composed of a photoacid that serves as our light-induced proton source for the initiation of the PD process. We use our probe to follow PD, and its pH dependence, on the surface of lipid vesicles composed of a zwitterionic headgroup, a negative headgroup, a headgroup that is composed only from the negative phosphate group, or…
Scheduling under the network of temporo-spatial proximity relationships
2017
We discuss and introduce to the schedulingeld a novel, qualitative optimization model - scheduling under the network of temporo-spatial proximity relationships.We introduce a half perimeter proximity measure as an objective of scheduling.We present and evaluate an incremental Sequence Pair neighborhood evaluation algorithm, applicable to both scheduling and rectangle packing problems in VLSI industry. In this paper, we discuss and introduce to the scheduling field a novel optimization objective - half perimeter proximity measure in scheduling under the network of temporo-spatial proximity relationships. The presented approach enables to qualitatively express various reasons of scheduling ce…
Micronutrition : de la théorie à l'application en clinique
2010
National audience; Les prévisions démographiques s'attendent à un accroissement important de la population âgée et très âgée dans les décennies à venir. La prévalence des pathologies oculaires occupe la deuxième place dans cette frange de la population, laissant entrevoir une réelle explosion du coût social et économique associé à la prise en charge des patients. Pourtant, des données théoriques suggèrent que certains nutriments, en particulier lipophiles, pourraient participer à prévenir les effets du vieillissement sur la rétine et le développement pathologique. Ces hypothèses sont corroborées par des données épidémiologiques qui renforcent l'association entre la consommation d'acides gra…
Validation of a Work Engagement Scale. Profi les associated with high Performance and Job Satisfaction
2017
El objetivo principal de este estudio consistía en la validación de una escala para la evaluación del work engagement -compromiso con el trabajo-, considerado como una presencia psicológica en el rol que incluye atención, absorción y energía dirigida a tareas laborales. Mediante análisis factorial confirmatorio, estimación de la consistencia interna y evidencias de validez convergente y discriminante, se confirma que la Escala Argentina de Compromiso con el Trabajo es una prueba válida y confiable para su uso en población argentina. Además, se buscó analizar si existen diferencias en los niveles de work engagement de acuerdo con variables individuales y organizacionales. Se observaron mayor…
Psychosocial Risk Factors and Psychopathological Outcomes: Preliminary Findings in Italian Pregnant Women
2023
The perinatal period may represent a particularly challenging time for expecting parents. Previous studies have highlighted an association between several perinatal risk conditions (e.g., childhood maltreatment, poor social support, and stress levels) and the development of psychopathological symptoms in pregnant women, especially depression symptoms. The current study examined the effects of psychosocial risk factors (childhood maltreatment, poor social support, and stressful events) on anxiety, depression, perceived stress, irritability/anger, relationship problems, psychosomatic symptoms, specific physiological problems, and addiction/at-risk behaviors. Sixty-one pregnant women (age rang…
Levels and Changes of Physical Activity in Adolescents during the COVID-19 Pandemic: Contextualizing Urban vs. Rural Living Environment
2020
The COVID-19 pandemic and the social distancing implemented shortly after influence physical activity levels (PALs). The purpose of this investigation was to evaluate the changes in PAL and factors associated with PALs among Croatian adolescents while considering the impact of community (urban vs. rural living environment). The sample included 823 adolescents (mean age: 16.5 ±
Intellectual Property Rights: An Economic Approach
2014
Abstract This paper aims to analyse the intellectual property rights from an economic perspective. The paper is discussing the points of view of well known economists in relation to the positive and negative impacts of the intellectual property systems. It brings also into discussion the role of IPR as a barrier to entry and a mean to restrict competition and to favour monopoly situations.
A control strategy based on intelligent algorithm (PSO) to perform electrical stimulation systems
2017
International audience; Adjusting stimulation parameters using control strategy based on reliable mathematical model that can predict perfectly the muscle response, may improve the efficiency of Functional Electrical Stimulation (FES) systems. In the present project, we investigate the PID control tuning based on the Particle Swarm Optimization (PSO) algorithm at the first time in neuro-muscular systems for updating automatically the stimulation pulse amplitude to track a desired force profiles. In the beginning, The PSO algorithm is used to identify unknown force model parameters. Next, optimal PID gains are found by the same intelligent algorithm to improve the control system. The obtaine…
Extraction Methods of Essential Oils From Herbs and Spices
2017
International audience; This chapter describes both conventional and non‐conventional extraction methods of essential oils (EOs) from herbs and spices. Although hydrodistillation, steam distillation and solvent extraction are the most applied methods, several non‐conventional technologies have been evaluated, especially in respect to EO recovery, and a great potential has been attributed to these non‐conventional methods. For instance, ultrasound, microwave, supercritical fluid, pulsed electric fields, ohmic‐heating and microwave (MW) extraction techniques applied alone or combined with other techniques are potent tools to obtain EOs in a 'green' way from natural resources such as aromatic …
Energy level determination of purine containing blue light emitting organic compounds
2018
Organic light emitting diodes (OLED) have found their applications in the mobile and TV screens. Till now the commercially available diodes are made by expensive thermal evaporation in a vacuum. The costs of OLED fabrication could be decreased by applying low-cost wet casting methods, for example, spin-coating. In this work, we have studied a group of blue light emitting purine derivatives which could potentially be used in OLEDs. The advantage of these compounds is their ability to form amorphous thin films from solutions. All the thin films were prepared by the spincoating method from chloroform solution on ITO glass. The position of hole and electron transport energy levels is important …