412 research outputs found
Структура сварных соединений наноструктурированного титана, полученных методом контактной сварки
The paper presents the research of the weld structure of two Ti specimens of the type VT6 having nano- and submicrocrystalline structures. Electrical contact welding is used to obtain welds. The acicular structure is formed in the weld area. Two types of defects are detected, namely micropores and microcracks
Invariant recognition of polychromatic images of Vibrio cholerae O1
7 pages, 5 figures.-- ©2002 Society of Photo-Optical Instrumentation Engineers.Cholera is an acute intestinal infectious disease. It has claimed many lives throughout history, and it continues to be a global health threat. Cholera is considered one of the most important emergence diseases due its relation with global climate changes. Automated methods such as optical systems represent a new trend to make more accurate measurements of the presence and quantity of this microorganism in its natural environment. Automatic systems eliminate observer bias and reduce the analysis time.We evaluate the utility of coherent optical systems with invariant correlation for the recognition of Vibrio cholerae O1. Images of scenes are recorded with a CCD camera and decomposed in three RGB channels. A numeric simulation is developed to identify the bacteria in the different samples through an invariant correlation technique. There is no variation when we repeat the correlation and the variation between images correlation is minimum. The position-, scale-, and rotation-invariant recognition is made with a scale transform through the Mellin transform. The algorithm to recognize Vibrio cholerae O1 is the presence of correlation peaks in the green channel output and their absence in red and blue channels. The discrimination criterion is the presence of correlation peaks in red, green, and blue channels.Peer reviewe
Curso "Propiedad intelectual y servicios de información"
Sección: Noticias. Noticias internasEl pasado mes de octubre tuvo lugar en Madrid entre los días 17 y 19, el Curso “Propiedad intelectual y servicios de información”, organizado por la Unidad de Coordinación de Bibliotecas y el Gabinete de Formación del CSIC.N
СИМВОЛИКА «ХРАМА В СЕРДЦЕ» ВО ФРАНЦУЗСКОЙ РОМАНТИЧЕСКОЙ ЛИТЕРАТУРЕ 1820-Х ГГ.
В статье романтическая символика храма и сердца рассматривается в аналитической традиции Г. Башляра. Французская романтическая поэзия перших десятиріч ХІХ ст. сохранила руссоистскую стилистику, однако актуализировала в новой мифопоэтической форме стихию человеческих чувств в их связи со стихиями природы и трансендентностью
Mechanical modeling of the maturation process for tissue-engineered implants: application to biohybrid heart valves
The development of tissue-engineered cardiovascular implants can improve the
lives of large segments of our society who suffer from cardiovascular diseases.
Regenerative tissues are fabricated using a process called tissue maturation.
Furthermore, it is highly challenging to produce cardiovascular regenerative
implants with sufficient mechanical strength to withstand the loading
conditions within the human body. Therefore, biohybrid implants for which the
regenerative tissue is reinforced by standard reinforcement material (e.g.
textile or 3d printed scaffold) can be an interesting solution. In silico
models can significantly contribute to characterizing, designing, and
optimizing biohybrid implants. The first step towards this goal is to develop a
computational model for the maturation process of tissue-engineered implants.
This paper focuses on the mechanical modeling of textile-reinforced
tissue-engineered cardiovascular implants. First, we propose an energy-based
approach to compute the collagen evolution during the maturation process. Then,
we apply the concept of structural tensors to model the anisotropic behavior of
the extracellular matrix and the textile scaffold. Next, the newly developed
material model is embedded into a special solid-shell finite element
formulation with reduced integration. Finally, we use our framework to compute
two structural problems: a pressurized shell construct and a tubular-shaped
heart valve. The results show the ability of the model to predict collagen
growth in response to the boundary conditions applied during the maturation
process. Consequently, we can predict the implant's mechanical response, such
as the deformation and stresses of the implant.Comment: Preprint submitted to Elsevie
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