Search results for "aging"
showing 10 items of 10496 documents
Neutron Radiography Visualization of Solid Particles in Stirring Liquid Metal
2015
Abstract This paper presents the analysis of the first dynamic neutron radiography experiment that visualized motion of solid particles in liquid metal, which was stirred by a system of four counter-rotating magnets. The paper also contains the quantitative results derived from neutron images: the distribution of particle concentration, number of admixed particles and velocities as functions of the magnet rotation speed.
Uso de redes sociales online en personas mayores de 55 años : un análisis exploratorio
2012
Es una aproximación cualitativa al uso y percepción que tienen los mayores de 55 años, de las tecnologías de la comunicación e información (TIC); Concretamente del uso de las redes sociales online. Mediante la técnica de los grupos de discusión trataremos de buscar los prejuicios, mitos conocimientos, motivaciones, barreras, etc. del uso o no de las redes sociales online. It is a qualitative approach to the use and perception of over 55 years of technology and information communication technology (ICT), specifically the use of online social networks. By the technique of focus groups will try to find the prejudices, myths, knowledge, motivations, barriers, etc.. use or not online social netw…
The Effect of the Range of a Modulating Phase Mask on the Retrieval of a Complex Object from Intensity Measurements
2021
The authors have been supported by the postdoctoral project (1.1.1.2/16/I/001, 1.1.1.2/VIAA/1/16/199), the CAMART2 project (grant agreement ID 739508), the Latvian Investment and Development Agency (LIDA) project (KC-PI-2017/105), and the grant for the Latvian State Emeritus Scientists.
A study of Type B uncertainties associated with the photoelectric effect in low-energy Monte Carlo simulations
2021
The goal of this manuscript is to estimate Type B uncertainties in absorbed-dose calculations arising from the different implementations in current state-of-the-art Monte Carlo codes of low-energy photon cross-sections (<200 keV). Monte Carlo simulations are carried out using three codes widely used in the low-energy domain: PENELOPE-2018, EGSnrc, and MCNP. Mass energy-absorption coefficients for water, air, graphite, and their respective ratios; absorbed dose; and photon-fluence spectra are considered. Benchmark simulations using similar cross-sections have been performed. The differences observed between these quantities when different cross-sections are considered are taken to be a go…
Problem-Based Learning in Professional Studies from the Physiotherapy Students’ Perspective
2018
The aim of the study was to investigate how physiotherapy students using a problem-based learning approach develop into experts during higher education, and answers the question: How do physiotherapy students at bachelor’s level understand the problem-based learning approach while learning to become professionals? PBL is examined using interpretative phenomenological analysis (IPA) of longitudinal data written by 15 voluntary students from two different higher education institutions and collected during 3.5 years. The main results on the new way of learning strengthen earlier conceptions of the importance of reflection in the learning process. The PBL method activates a reflection process b…
Deepening Inside the Pictorial Layers of Etruscan Sarcophagus of Hasti Afunei: An Innovative Micro-Sampling Technique for Raman/SERS Analyses
2019
The Hasti Afunei sarcophagus is a large Etruscan urn, made up of two chalky alabaster monoliths. Dated from the last quarter of the third century BC, it was found in 1826 in the small town of Chiusi (Tuscany- Il Colle place) by a landowner, Pietro Bonci Casuccini, who made it part of his private collection. The noble owner&rsquo
Comparison of 99mTc-Labeled Colloid SPECT/CT and Planar Lymphoscintigraphy in Sentinel Lymph Node Detection in Patients with Melanoma: A Meta-Analysis
2020
We compared the detection rate (DR) for sentinel lymph nodes (SLNS), the number of SLNs and the subjects with additional SLNs of single-photon emission computed tomography (SPECT/CT) and planar lymphoscintigraphy (PL) in patients with melanoma. Furthermore, we evaluated the impact of SPECT/CT on surgical plans. Articles containing head-to-head comparisons between SPECT/CT and PL were searched in Pubmed/MEDLINE and Scopus. The literature search was updated until December 31st, 2019. DR was calculated on a per-patient-based analysis; the studies were pooled by their odds ratios (ORs) with a random effects model to assess the significance of difference (p < 0.05). The number of additional S…
Plasma Dynamics Characterization for Improvement of Resonantly Enhanced Harmonics Generation in Indium and Tin Laser-Produced Plasmas
2022
R.A.G. is grateful to H. Kuroda for providing the access to the laser facility. As a Center of Excellence, the Institute of Solid State Physics at the University of Latvia received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement no. 739508, project CAMART².
Toward Sustainable PLA-Based Multilayer Complexes with Improved Barrier Properties
2019
Poly(lactic acid) or PLA is currently considered as one of the most promising substitutes of conventional plastics, with low environmental impact, especially for food packaging applications. Nevertheless, some drawbacks, such as high permeability to oxygen, are still limiting its industrial applications. The objective of this study was to highly increase the oxygen barrier performance of PLA without compromising its sustainable nature and following the principles of circular economy perspective. Coproducts coming from mill industries, such as wheat gluten proteins (WG), were used to produce PLA-WG-PLA multilayer complexes with improved barrier performance. Different technologies of industri…