Nonlinear dynamics of open quantum systems

The evolution of a composite closed system using the integral wave equation with the kernel in the form of path integral is considered. It is supposed that a quantum particle is a subsystem of this system. The evolution of the reduced density matrix of the subsystem is described on the basis of the integral wave equation for a composite closed system. The equation for the density matrix for such a system is derived. This equation is nonlinear and depends on the history of the processes in the closed system. It is shown that, in general, the reduced density matrix trace does not conserve in the evolution processes progressing in open systems and the procedure of the trace normalization is necessary as the mathematical image of a real nonlocal physical process. The wave function collapse and EPR correlation are described using this approach.Comment: 8

Macroscopic Body Motion in Terms of Quantum Evolution

Macroscopic body is considered as a system, consisting of an infinite number of quantum particles. Mechanical motion of the system center of mass in physical space is described, using Feynman's representation of the quantum evolution. It is shown that the center of mass of the system moves accordingly with the minimum action principle if action functional is much higher then Plank's constant.Comment: 7

Quantum Particle Motion in Physical Space

Using Feynman's representation of the quantum evolution and considering a quantum particle as a matter field (continuous medium), it is shown that individual particles of the field have unique paths of the motion. This allows describing motion of the quantum particle continuous medium by Lagrange's method. It is shown that form of the real individual particle path is determined by classical minimum action principle.Comment: 5 page

Towards better understanding of the amorphous silica - Alkali reactions and the means of preventing glass aggregate expansion in concrete

The effect of quantity and characteristics of the components of amorphous silica - alkali reactions, based on the research carried at the CSIRO Laboratories in Australia and by the author are discussed. Conditions under which the expansion of silica-gel can be reduced to a safe level or even completely eliminated are presented. The emphasis is made on the commercially viable and the most economical means of the safe use of crushed soda-lime glasses (which account for about ninety percent of all manufactured glasses) as an aggregate in structural, durable and dimensionally stable concretes, in which hydraulic cements are used as a binder. With the depletion of good quality natural aggregates from quarries located in the proximity of construction and development sites, the use of recycled materials becomes particularly important in the current climate of global recession. It should be emphasized, however, that the results of these findings may not be universal, and when applied to the specific local conditions (both - glass and hydraulic cements) should be verified in the laboratory tests

Parental Quality of Life in the Framework of Paediatric Chronic Gastrointestinal Disease

Chronic gastrointestinal diseases, such as inflammatory bowel disease (IBD) and celiac disease (CD), might have impact not only on the affected child but also on their parents since inside the family framework, a change in each member may have influence on the whole system. The aim of this study was to test the hypothesis that parents whose children have IBD or CD will have a lower quality of life (QoL) compared to parents of healthy children, as well as that lower QoL will be found among parents who perceive lower health related quality of life (HRQOL) of their child. 55 parents of children with IBD, 49 of CD and 53 parents of healthy children were included in the study. Children were aged 7–18 years. In order to measure parental QoL, a Croatian version of the WHOQOL-BREF questionnaire was administered, with four domains: physical health, psychological health, social relationship and environment. The Total QoL was calculated as a sum of all domain items. The parent-proxy report of children’s HRQOL, PedsQLTM 4.0 Generic Core Scales was used.Main result shows that parents of children with IBD report a significantly lower psychological health, compared to parents of other children, and significantly lower physical health compared to parents of healthy children. Among parents of children with CD and parents of healthy children, better parental Total QoL was significantly correlated with better parental report of children’s HRQOL, while for parents of children with IBD those associations were not found. Results of study show association between presence of the disease in offspring with poorer parental QoL, thus highlight the importance of supporting not only children with chronic disease but also involving their parents in psychosocial interventions, as well as supporting the patient’s association groups which gather both children with chronic disease and their parents