In this paper we present a formalization of the specialization process of organisms as given by N. Rashevsky. This is done by means of gluing constructions of graphs and then we formalize the evolution of organisms by...
In this paper we present a formalization of the specialization process of organisms as given by N. Rashevsky. This is done by means of gluing constructions of graphs and then we formalize the evolution of organisms by successive specialization using the concepts of graph grammars. In fact, this is an extension to higher dimensions of developmental processes as described by L -systems and the development of radial patterns. The gluing construction for graphs and the algebraically formulated theory of graph grammars are developed in detail for the special case of unlabeled graphs in Sections 2 and 4, which can be read separately. In the other three sections the theory is applied to processes of specialization and evolution in biology and several illustrating examples are given.
Interaction of hypersound and light inside laser cavity with Stokes feedback;quantum equations of motion for creation operators of laser and Stokes modes, and acoustic mode coupled to them, are derived;using quasi-cla...
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Interaction of hypersound and light inside laser cavity with Stokes feedback;quantum equations of motion for creation operators of laser and Stokes modes, and acoustic mode coupled to them, are derived;using quasi-classical approximation, these equations are transformed into system of nonlinear differential equations for classical field amplitudes;stationary solutions of system are obtained and conditions under which such solutions exist are determined;instability criteria are established.
This study was designed to assess the effect of soya phosphatidylcholine (SPC) against ischemia/reperfusion (I/R) injury and the possible underlying mechanism using experimental and computational studies. I/R injury w...
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This study was designed to assess the effect of soya phosphatidylcholine (SPC) against ischemia/reperfusion (I/R) injury and the possible underlying mechanism using experimental and computational studies. I/R injury was induced by global ischemia for 30 min followed by reperfusion for 120 min. The perfusion of the SPC was performed for 10 min before inducing global ischemia. In the mechanistic study, the involvement of specific cellular pathways was identified using various inhibitors such as ATP-dependent potassium channel (K-ATP) inhibitor (glibenclamide), protein kinase C (PKC) inhibitor (chelerythrine), non-selective nitric oxide synthase inhibitor (L-NAME), and endothelium remover (Triton X-100). The computational study of various ligands was performed on toll-like receptor 4 (TLR4) protein using AutoDock version 4.0. SPC (100 mu M) significantly decreased the levels of cardiac damage markers and %infarction compared with the vehicle control (VC). Furthermore, cardiodynamics (indices of left ventricular contraction (dp/dt(max)), indices of left ventricular relaxation (dp/dt(min)), coronary flow, and antioxidant enzyme levels were significantly improved as compared with VC. This protective effect was attenuated by glibenclamide, chelerythrine, and Triton X-100, but it was not attenuated by L-NAME. The computational study showed a significant bonding affinity of SPC to the TLR4-MD2 complex. Thus, SPC reduced myocardial I/R injury in isolated perfused rat hearts, which might be governed by the KATP channel, PKC, endothelium response, and TLR4-MyD88 signaling pathway.
Natural selection explains how life has evolved over millions of years from more primitive forms. The speed at which this happens, however, has sometimes defied formal explanations when based on random (uniformly dist...
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