1,631 research outputs found
On A New Formulation of Micro-phenomena: Basic Principles, Stationary Fields And Beyond
In a series of essays, beginning with this article, we are going to develop a
new formulation of micro-phenomena based on the principles of reality and
causality. The new theory provides with us a new depiction of micro-phenomena
assuming an unified concept of information, matter and energy. So, we suppose
that in a definite micro-physical context (including other interacting
particles), each particle is enfolded by a probability field whose existence is
contingent upon the existence of the particle, but it can locally affect the
physical status of the particle in a context-dependent manner. The dynamics of
the whole particle-field system obeys deterministic equations in a manner that
when the particle is subjected to a conservative force, the field also
experiences a conservative complex force which its form is determined by the
dynamics of particle. So, the field is endowed with a given amount of energy,
but its value is contingent upon the physical conditions the particle is
subjected to. Based on the energy balance of the particle and its associated
field, we argue why the field has a probabilistic objective nature. In such a
way, the basic elements of this new formulation, its application for some
stationary states and its nonlinear generalization for conservative systems are
discussed here.Comment: 35 pages, 5 figures, 3 appendice
Connectivity of pseudomanifold graphs from an algebraic point of view
The connectivity of graphs of simplicial and polytopal complexes is a
classical subject going back at least to Steinitz, and the topic has since been
studied by many authors, including Balinski, Barnette, Athanasiadis and
Bjorner. In this note, we provide a unifying approach which allows us to obtain
more general results. Moreover, we provide a relation to commutative algebra by
relating connectivity problems to graded Betti numbers of the associated
Stanley--Reisner rings.Comment: 4 pages, minor change
Fluoxetine selectively induces p53-independent apoptosis in human colorectal cancer cells
Fluoxetine has been shown to induce anti-tumour activity. The aim of this study was to determine the effect of fluoxetine on HCT116+/+ and p53 gene-depleted HCT116-/- human colorectal cancer cells and the mechanisms, including potential p53-dependence, of its action. Fluoxetine-induced apoptosis was investigated by mitochondrial membrane potential assay, Annexin V assay, two-step cell cycle analysis using NC-3000â„¢ system and pharmacological inhibition assays. Fluoxetine induced very selectively concentration-dependent apoptosis in human colorectal cancer cells by altering mitochondrial membrane potential and inducing translocation of phosphatidylserine to the outer membrane layer. Further evidence of the preponderance of apoptosis in fluoxetine-induced cell death is provided by the finding that the cell death was not blocked by inhibitors of parthanatos, a form of cell death that results from overactivation of the enzyme poly (ADP-ribose) polymerase (PARP) but is different from apoptosis. Data obtained indicate fluoxetine caused cell cycle event at Sub-G1 and G0/G1 phases in both cell lines. In terms of apoptosis, there is no significant difference between the responses of the two cell lines to fluoxetine.
In conclusion, fluoxetine's cytotoxicity induces mainly apoptosis and causes DNA fragmentation in human colorectal cancer cells, which seemed to be independent of the p53 protein, as no significant difference in death profiles in response to fluoxetine treatment was observed in both the p53-intact and the p53-deleted cell lines. Fluoxetine, therefore, has potential for being repurposed as a drug for the treatment of colon cancer and thus deserves further investigations in this context
A Comparative Study of the Immscible Density Currents Using the SPH And VOF-LES Methods
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
Thermodynamic Optimization of a Geothermal Power Plant with a Genetic Algorithm in Two Stages
Due to the harmful effects and depletion of non-renewable energy resources, the major concerns are focused on using renewable energy resources. Among them, the geothermal energy has a high potential in volcano regions such as the Middle East. The optimization of an organic Rankine cycle with a geothermal heat source is investigated based on a genetic algorithm having two stages. In the first stage, the optimal variables are the depth of the well and the extraction flow rate of the geothermal fluid mass. The optimal value of the depth of the well, extraction mass flow rate, and the geothermal fluid temperature is found to be 2100 m, 15 kg/s, and 150 °C. In the second stage, the efficiency and output power of the power plant are optimized. To achieve maximum output power as well as cycle efficiency, the optimization variable is the maximum organic fluid pressure in the high-temperature heat exchanger. The optimum values of energy efficiency and cycle power production are equal to 0.433 MW and 14.1%, respectively
Nonlinear finite element analysis of strength and durability of reinforced concrete and composite structures
The finite element method has emerged as the most powerful and versatile numerical method for solving a wide range of physical problems in science and engineering. Today a large number of commercial programs exist that can be used to solve diverse problems in structural and fluid mechanics, heat transfer and many other phenomena. However, certain critical problems related to durability of concrete structures, especially corrosion of reinforcement, cannot be readily solved using the available software. This paper presents two finite element formulations, developed by the writers, one dealing with the nonlinear analysis of composite concrete-steel bridges, and the other with the durability of concrete structures, with emphasis on the corrosion of reinforcement. The validity and accuracy of the proposed models are demonstrated by comparing their results with appropriate experimental data
Time parameterization and stationary distributions in a relativistic gas
In this paper we consider the effect of different time parameterizations on
the stationary velocity distribution function for a relativistic gas. We
clarify the distinction between two such distributions, namely the J\"{u}ttner
and the modified J\"{u}ttner distributions. Using a recently proposed model of
a relativistic gas, we show that the obtained results for the proper-time
averaging does not lead to modified J\"{u}ttner distribution (as recently
conjectured), but introduces only a Lorentz factor to the well-known
J\"{u}ttner function which results from observer-time averaging. We obtain
results for rest frame as well as moving frame in order to support our claim.Comment: 5 pages, 2 figure
Further investigation of the effects of 5-hydroxytryptamine, 8-OH-DPAT and DOI to mediate contraction and relaxation responses in the intestine and emesis in Suncus murinus
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