Entropy in the evaluation of tremor parameters from the position of the chaos theory and self-organization

2016 ◽  
Vol 10 (1) ◽  
pp. 0-0
Author(s):  
Черников ◽  
N. Chernikov ◽  
Горбунов ◽  
D. Gorbunov ◽  
Берестин ◽  
...  

The evolution of biological systems on the example of measuring the parameters of tremor and values of the Shannon entropy of the same test (15 measurements on 15 samples) was carried out. Changes tremor pa-rameters observed both in the same subject or a group of subjects. The statistical parameters are unique, they are specific to a particular time interval Δt. In the framework of the theory of chaos, self-organization and for this reason it is always calculated in the two-dimensional quasi-attractor tremorograms or three-dimensional phase space of states. Calculation of entropy values Shannon showed that statistically the sample entropy does not vary, but the result of the matrix pairwise comparison of samples of entropy is similar to the result of the matrix pairwise comparison of samples from a random generator. The article demonstrates that the method of calculating the Shannon entropy E can be used in assessing the homeostasis parameters tremor regulation sys-tem, but it has low sensitivity.

2015 ◽  
Vol 22 (2) ◽  
pp. 32-38
Author(s):  
Григоренко ◽  
V. Grigorenko ◽  
Горбунов ◽  
D. Gorbunov ◽  
Еськов ◽  
...  

The paper shows the feasibility of applying the method of multi-dimensional phase space as a quantitative measure for the evaluation of chaotic dynamics on the example of the muscles (flexor of the little finger). The method of multi-dimensional phase space was used. In the study and modeling of complex biological objects (complexity) there is the possibility of introducing traditional physical methods in biological research and new methods based on the chaos theory and self-organization. As a measure of the state of the neuromuscular system of the person (weak muscle tension and strong, almost the maximum force), the authors used quasi-attractors volumes of multidimensional phase space. This enables identification of the actual measurements of the parameters of the functional state with weak muscles (Fi = 5 daN) and strong (Fi = 10 daN) static stress. The authors built a timebase signal received from the electromyograph and the autocorrelation function A(t) of signal. A biomechanical analysis of the state of the system is carried out on the basis of comparison of the volume VG quasi attractor, as well as on the basis of the analysis of the Shannon entropy E. Volume of quasi attractor VG displacements under low load is slightly less than the same volume displacement VG with strong exertion of the muscles of the flexor of the little finger, exactly the same as the values of the Shannon entropy under a heavy load increases compared to the values obtained under low load the muscles.


2003 ◽  
Vol 70 ◽  
pp. 201-212 ◽  
Author(s):  
Hideaki Nagase ◽  
Keith Brew

The tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of the matrix metalloproteinases (MMPs), enzymes that play central roles in the degradation of extracellular matrix components. The balance between MMPs and TIMPs is important in the maintenance of tissues, and its disruption affects tissue homoeostasis. Four related TIMPs (TIMP-1 to TIMP-4) can each form a complex with MMPs in a 1:1 stoichiometry with high affinity, but their inhibitory activities towards different MMPs are not particularly selective. The three-dimensional structures of TIMP-MMP complexes reveal that TIMPs have an extended ridge structure that slots into the active site of MMPs. Mutation of three separate residues in the ridge, at positions 2, 4 and 68 in the amino acid sequence of the N-terminal inhibitory domain of TIMP-1 (N-TIMP-1), separately and in combination has produced N-TIMP-1 variants with higher binding affinity and specificity for individual MMPs. TIMP-3 is unique in that it inhibits not only MMPs, but also several ADAM (a disintegrin and metalloproteinase) and ADAMTS (ADAM with thrombospondin motifs) metalloproteinases. Inhibition of the latter groups of metalloproteinases, as exemplified with ADAMTS-4 (aggrecanase 1), requires additional structural elements in TIMP-3 that have not yet been identified. Knowledge of the structural basis of the inhibitory action of TIMPs will facilitate the design of selective TIMP variants for investigating the biological roles of specific MMPs and for developing therapeutic interventions for MMP-associated diseases.


2012 ◽  
Vol 9 (1) ◽  
pp. 142-146
Author(s):  
O.A. Solnyshkina

In this work the 3D dynamics of two immiscible liquids in unbounded domain at low Reynolds numbers is considered. The numerical method is based on the boundary element method, which is very efficient for simulation of the three-dimensional problems in infinite domains. To accelerate calculations and increase the problem size, a heterogeneous approach to parallelization of the computations on the central (CPU) and graphics (GPU) processors is applied. To accelerate the iterative solver (GMRES) and overcome the limitations associated with the size of the memory of the computation system, the software component of the matrix-vector product


2012 ◽  
Vol 27 (28) ◽  
pp. 1250164
Author(s):  
J. MANUEL GARCÍA-ISLAS

In the three-dimensional spin foam model of quantum gravity with a cosmological constant, there exists a set of observables associated with spin network graphs. A set of probabilities is calculated from these observables, and hence the associated Shannon entropy can be defined. We present the Shannon entropy associated with these observables and find some interesting bounded inequalities. The problem relates measurements, entropy and information theory in a simple way which we explain.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pradeep Kumar ◽  
Viness Pillay ◽  
Yahya E. Choonara

AbstractThree-dimensional porous scaffolds are widely employed in tissue engineering and regenerative medicine for their ability to carry bioactives and cells; and for their platform properties to allow for bridging-the-gap within an injured tissue. This study describes the effect of various methoxypolyethylene glycol (mPEG) derivatives (mPEG (-OCH3 functionality), mPEG-aldehyde (mPEG-CHO) and mPEG-acetic acid (mPEG-COOH)) on the morphology and physical properties of chemically crosslinked, semi-interpenetrating polymer network (IPN), chitosan (CHT)/mPEG blend cryosponges. Physicochemical and molecular characterization revealed that the –CHO and –COOH functional groups in mPEG derivatives interacted with the –NH2 functionality of the chitosan chain. The distinguishing feature of the cryosponges was their unique morphological features such as fringe thread-, pebble-, curved quartz crystal-, crystal flower-; and canyon-like structures. The morphological data was well corroborated by the image processing data and physisorption curves corresponding to Type II isotherm with open hysteresis loops. Functionalization of mPEG had no evident influence on the macro-mechanical properties of the cryosponges but increased the matrix strength as determined by the rheomechanical analyses. The cryosponges were able to deliver bioactives (dexamethasone and curcumin) over 10 days, showed varied matrix degradation profiles, and supported neuronal cells on the matrix surface. In addition, in silico simulations confirmed the compatibility and molecular stability of the CHT/mPEG blend compositions. In conclusion, the study confirmed that significant morphological variations may be induced by minimal functionalization and crosslinking of biomaterials.


1982 ◽  
Vol 92 (3) ◽  
pp. 747-752 ◽  
Author(s):  
WS Haston ◽  
JM Shields ◽  
PC Wilkinson

The adhesion and locomotion of mouse peripheral lymph node lymphocytes on 2-D protein- coated substrata and in 3-D matrices were compared. Lymphocytes did not adhere to, or migrate on, 2-D substrata suck as serum- or fibronectin-coated glass. They did attach to and migrate in hydrated 3-D collagen lattices. When the collagen was dehydrated to form a 2-D surface, lymphocyte attachment to it was reduced. We propose that lymphocytes, which are poorly adhesive, are able to attach to and migrate in 3-D matrices by a nonadhesive mechanism such as the extension and expansion of pseudopodia through gaps in the matrix, which could provide purchase for movement in the absence of discrete intermolecular adhesions. This was supported by studies using serum-coated micropore filters, since lymphocytes attached to and migrated into filters with pore sizes large enough (3 or 8 mum) to allow pseudopod penetration but did not attach to filters made of an identical material (cellulose esters) but of narrow pore size (0.22 or 0.45 mum). Cinematographic studies of lymphocyte locomotion in collagen gels were also consistent with the above hypothesis, since lymphocytes showed a more variable morphology than is typically seen on plane surfaces, with formation of many small pseudopodia expanded to give a marked constriction between the cell and the pseudopod. These extensions often remained fixed with respect to the environment as the lymphocyte moved away from or past them. This suggests that the pseudopodia were inserted into gaps in the gel matrix and acted as anchorage points for locomotion.


2005 ◽  
Vol 3 (3) ◽  
pp. 335-354 ◽  
Author(s):  
Clarissa Ribeiro Pereira de Almeida ◽  
Anja Pratschke ◽  
Renata La Rocca

This paper draws on current research on complexity and design process in architecture and offers a proposal for how architects might bring complex thought to bear on the understanding of design process as a complex system, to understand architecture as a way of organizing events, and of organizing interaction. Our intention is to explore the hypothesis that the basic characteristics of complex systems – emergence, nonlinearity, self-organization, hologramaticity, and so forth – can function as effective tools for conceptualization that can usefully extend the understanding of the way architects think and act throughout the design process. To illustrate the discussions, we show how architects might bring complex thought inside a transdisciplinary design process by using models such as software engineering diagrams, and three-dimensional modeling network environments such as media to integrate, connect and ‘trans–act’.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ilse Valenzuela Matus ◽  
Jorge Lino Alves ◽  
Joaquim Góis ◽  
Augusto Barata da Rocha ◽  
Rui Neto ◽  
...  

Purpose The purpose of this paper is to prove and qualify the influence of textured surface substrates morphology and chemical composition on the growth and propagation of transplanted corals. Use additive manufacturing and silicone moulds for converting three-dimensional samples into limestone mortar with white Portland cement substrates for coral growth. Design/methodology/approach Tiles samples were designed and printed with different geometries and textures inspired by nature marine environment. Commercial coral frag tiles were analysed through scanning electron microscopy (SEM) to identify the main chemical elements. Raw materials and coral species were selected. New base substrates were manufactured and deployed into a closed-circuit aquarium to monitor the coral weekly evolution process and analyse the results obtained. Findings Experimental results provided positive statistical parameters for future implementation tests, concluding that the intensity of textured surface, interfered favourably in the coralline algae biofilm growth. The chemical composition and design of the substrates were determinant factors for successful coral propagation. Recesses and cavities mimic the natural rocks aspect and promoted the presence and interaction of other species that favour the richness of the ecosystem. Originality/value Additive manufacturing provided an innovative method of production for ecology restoration areas, allowing rapid prototyping of substrates with high complexity morphologies, a critical and fundamental attribute to guarantee coral growth and Crustose Coralline Algae. The result of this study showed the feasibility of this approach using three-dimensional printing technologies.


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