scholarly journals Homeostatic model of human thermoregulation with bi-stability

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Veronika Hajnová ◽  
Filip Zlámal ◽  
Peter Lenárt ◽  
Julie Bienertova-Vasku
Keyword(s):  
Mathematical Model ◽  
Thermal Adaptation ◽  
Living System ◽  
Living Systems ◽  
Feedback Mechanisms ◽  
Starting Point ◽  
Homeostatic Model ◽  
Critical Care Patients ◽  
Adaptation Costs ◽  
Human Thermoregulation

AbstractAll homoiothermic organisms are capable of maintaining a stable body temperature using various negative feedback mechanisms. However, current models cannot satisfactorily describe the thermal adaptation of homoiothermic living systems in a physiologically meaningful way. Previously, we introduced stress entropic load, a novel variable designed to quantify adaptation costs, i.e. the stress of the organism, using a thermodynamic approach. In this study, we use stress entropic load as a starting point for the construction of a novel dynamical model of human thermoregulation. This model exhibits bi-stable mechanisms, a physiologically plausible features which has thus far not been demonstrated using a mathematical model. This finding allows us to predict critical points at which a living system, in this case a human body, may proceed towards two stabilities, only one of which is compatible with being alive. In the future, this may allow us to quantify not only the direction but rather the extent of therapeutic intervention in critical care patients.

Discontinuous and continuous transitions of collective behaviors in living systems

2021 ◽  
Author(s):  
Xu Li ◽  
Tingting Xue ◽  
Yu Sun ◽  
Jingfang Fan ◽  
Hui Li ◽  
...  
Keyword(s):  
Cognitive Abilities ◽  
Collective Motion ◽  
Finite Size ◽  
Continuous Phase ◽  
Living System ◽  
Living Systems ◽  
Finite Size Scaling ◽  
Continuous Transition ◽  
Collective Behaviors ◽  
Large Groups

Abstract Living systems are full of astonishing diversity and complexity of life. Despite differences in the length scales and cognitive abilities of these systems, collective motion of large groups of individuals can emerge. It is of great importance to seek for the fundamental principles of collective motion, such as phase transitions and their natures. Via an eigen microstate approach, we have found a discontinuous transition of density and a continuous transition of velocity in the Vicsek models of collective motion, which are identified by the finite-size scaling form of order-parameter. At strong noise, living systems behave like gas. With the decrease of noise, the interactions between the particles of a living system become stronger and make them come closer. The living system experiences then a discontinuous gas-liquid like transition of density. The even stronger interactions at smaller noise make the velocity directions of particles become ordered and there is a continuous phase transition of collective motion in addition.

scholarly journals Integrative concept of homeostasis: translating physiology into medicine

F1000Research ◽  
2014 ◽  
Vol 3 ◽  
pp. 299
Author(s):  
Ivan Spasojević
Keyword(s):  
Living System ◽  
Living Systems ◽  
Initial Condition ◽  
Adult Human ◽  
Input Side ◽  
Tremendous Amount ◽  
To Come ◽  
Integrative Concept ◽  
The One ◽  
Reductionist Approach

To truly understand living systems they must be viewed as a whole. In order to achieve this and to come to some law that living systems comply with, the reductionist approach, which has delivered a tremendous amount of data so far, should be complemented with integrative concepts. The current paper represents my humble attempt towards an integrative concept of homeostasis that would describe the (patho)physiological setup of adult human/mammal system, and that might be applicable in medicine. Homeostasis can be defined as time- and initial-condition-independent globally stabile state of non-equilibrium of a living system in which the interactions of system with the surroundings and internal processes are overall in balance or very near it. The presence of homeostasis or the shift from homeostasis of an adult human/mammal system can be described by equation that takes into account energy and informational input and output, catabolism and anabolism, oxidation and reduction, and entropy, where changes in the input should equal changes in the output within a specific period of time. Catabolism and oxidation are presented on the input side since the drive of the surroundings is to decompose and oxidize living systems, i.e. systems are under constant 'catabolic and oxidative pressure'. According to the equation, homeostasis might be regained by changing any of the input or output components in a proper manner (and within certain limits), not only the one(s) that has/have been changed in the first place resulting in the deviation from homeostasis.

Značaj saradnje školske ustanove i porodice za razvoj ličnosti učenika

2021 ◽  
Author(s):  
Jasmina Veljković ◽  
Keyword(s):  
School Climate ◽  
Relevant Literature ◽  
Living System ◽  
Parenting Skills ◽  
Pedagogical Documentation ◽  
Historical Method ◽  
Starting Point ◽  
The Family ◽  
Changing Patterns ◽  
The Individual

The family as a living system is an organizedand permanent whole with changing patterns of human behavior, ie the family is the first life and social environment in which the child finds himself and acquires the first experiences that form the starting point of the overall development of the individual. In addition to the family, the time that the child spends in school is relatively long, and accordingly, she manages to achieve her influence on the development and formation of the student's personality. The cooperation established between the family and the school can contribute to both parties in different ways, improving the general atmosphere, the school climate and improving the work of teachers and providing support for the development of the family and parenting skills. By studying the relevant literature, we want to determine the importance of cooperation between the family and the school for the development of students' personalities, which is also the basic goal. The paper uses the historical method, as the basic method of historical research and analysis of the content of pedagogical documentation.

scholarly journals Optical nanoscopy

2020 ◽  
Vol 43 (8) ◽  
pp. 385-455
Author(s):  
A. Diaspro ◽  
P. Bianchini
Keyword(s):  
Artificial Intelligence ◽  
Spatial Resolution ◽  
Scanning Probe Microscopy ◽  
Molecular Level ◽  
Super Resolution ◽  
Optical Microscope ◽  
Scanning Probe ◽  
Living Systems ◽  
Starting Point ◽  
Basic Concepts

Abstract This article deals with the developments of optical microscopy towards nanoscopy. Basic concepts of the methods implemented to obtain spatial super-resolution are described, along with concepts related to the study of biological systems at the molecular level. Fluorescence as a mechanism of contrast and spatial resolution will be the starting point to developing a multi-messenger optical microscope tunable down to the nanoscale in living systems. Moreover, the integration of optical nanoscopy with scanning probe microscopy and the charming possibility of using artificial intelligence approaches will be shortly outlined.

A two-dimensional transient mathematical model of human thermoregulation

1979 ◽  
Vol 237 (5) ◽  
pp. R266-R277 ◽  
Author(s):  
L. H. Kuznetz
Keyword(s):  
Mathematical Model ◽  
Heat Generation ◽  
Internal Heat ◽  
The Body ◽  
Transient Temperature ◽  
Spatial Direction ◽  
Temperature Variations ◽  
Spatial Dimensions ◽  
Skin Temperatures ◽  
Human Thermoregulation

Current models of human thermoregulation are limited in that they fail to account for temperature distribution in any spatial direction other than radially outward from the body centerline. They are therefore incapable of accounting for nonuniform environmental conditions or nonuniform heat generation from muscles or organs within the body. However, for many situations, these nonuniform conditions are commonplace and lead to disparate skin temperatures and heat loss rates on different sides of the same body compartement. A new mathematical model of human thermoregulation that has been developed and is presented here has the capability of predicting transient temperature variations in two spatial dimensions, both radially and angularly, as measured from the body centerline. In so doing, the model accounts for nonuniform environments and internal heat generation rates. Typical results from the model are demonstrated, and comparisons with available experimental data are also presented.

Art as a Living System: Interactive Computer Artworks

Leonardo ◽  
1999 ◽  
Vol 32 (3) ◽  
pp. 165-173 ◽  
Author(s):  
Christa Sommerer ◽  
Laurent Mignonneau
Keyword(s):  
Image Processing ◽  
Human Computer Interaction ◽  
Real Time ◽  
Artificial Life ◽  
Real Life ◽  
Living System ◽  
Living Systems ◽  
Time Interaction ◽  
The Individual ◽  
Interactive Installations

The authors design computer installations that integrate artificial life and real life by means of human-computer interaction. While exploring real-time interaction and evolutionary image processes, visitors to their interactive installations become essential parts of the systems by transferring the individual behaviors, emotions and personalities to the works' image processing. Images in these installations are not static, pre-fixed or predictable, but “living systems” themselves, representing minute changes in the viewers' interactions with the installations' evolutionary image processes.

ALGORITHMIC SUPPORT FOR SELECTING OPTIMAL TRAFFIC ROUTE OF MOTOR CONVOY OF RAPID REACTION BORDER COMMAND POST

2019 ◽  
pp. 25-35
Author(s):  
O. Borovyk ◽  
V. Kupelskiy
Keyword(s):  
Mathematical Model ◽  
Traffic Safety ◽  
The State ◽  
Optimal Route ◽  
The Road ◽  
Starting Point ◽  
Branching Points ◽  
The Matrix ◽  
The Status ◽  
Speed Function

The rapid response border commandant's office is a structural unit of the border detachment, designed to protect and strengthen the protection of a certain section of the state border, and must quickly redeploy its forces and assets. The success of the tasks assigned to the unit depends largely on the timeliness of arrival at the destination. Operational transportation of a significant amount of weapons, personnel and dissimilar cargoes on land is carried out using equipment. At the preparatory stage of the organization of transportation, the problem of forming the optimal composition of the convoy of equipment is solved. The existing road network provides a sufficiently large number of traffic routes between the starting and ending points. Moreover, this takes place even for insignificant distances between points of departure and destination. The specified conditions for multivariance in the selection. In addition, the choice of the route of movement depends on many auxiliary conditions: driver training, technical characteristics and reliability of vehicles, traffic safety, road and environmental conditions, distance and timing of transportation, and the like. Poor accounting of these factors in the aggregate may lead to the choice of an irrational route of movement, will not ensure the timely arrival of the unit at the destination, and may lead to the failure to fulfill certain tasks. Therefore, the task of choosing the optimal route of movement of the column of equipment is relevant. At the substantive level, the task looks like the justification of the mathematical model for choosing the optimal route for the column of equipment, if the criterion of optimality is minimizing the time it takes to move from the starting point to the destination. The authors formed a mathematical model of the given problem, proposed an algorithm for its solution for three cases: discrete-stochastic, discretely-determined and continuously-indefinite, and the corresponding software was developed. The choice of routes is carried out for three options, taking into account the fact that the change in the weights of the ribs can be carried out: at times when the column is at a certain vertex of the graph, and the update of the matrix of weights is carried out precisely at these moments. This is the case when a decision on the further route of movement is formed at the road branching points, taking into account the situation, the status of individual sections changes dynamically and data for which appears periodically; at times when the column is at a certain vertex of the graph, and for these moments, the matrix of weights that will occur when the column hits the vertex are known in advance. This is the case when a decision on the route of movement can be formed at the beginning of the movement, taking into account the known situation on the state of the roads, dynamically change, but data on which can be taken into account in advance; randomly depending on the speed of the column at a fixed point in time for which the column speed function is known.

scholarly journals REPLICATION AND EVOLUTION OF QUANTUM SPECIES

2004 ◽  
Vol 04 (03) ◽  
pp. R27-R38 ◽  
Author(s):  
ARUN K. PATI
Keyword(s):  
Quantum Information ◽  
Artificial Life ◽  
Biological Systems ◽  
Living System ◽  
Living Systems ◽  
Closed Universe ◽  
Basic Features

We dwell upon the physicist's conception of 'life' since Schrödinger and Wigner through to the modern-day language of living systems in the light of quantum information. We discuss some basic features of a living system such as ordinary replication and evolution in terms of quantum bio-information. We also discuss the principle of no-culling of living replicas. We show that in a collection of identical species there can be no entanglement between one of the mutated copies and the rest of the species in a closed universe. Even though these discussions revolve around 'artificial life' they may still be applicable in real biological systems under suitable conditions.

scholarly journals Comparative Simulation Study on Synchronous Generators Sudden Short Circuits

2009 ◽  
Vol 2009 ◽  
pp. 1-11 ◽  
Author(s):  
Lucian Lupşa-Tătaru
Keyword(s):  
Mathematical Model ◽  
Time Domain ◽  
Short Circuit ◽  
Structural Equations ◽  
Process Models ◽  
State Variables ◽  
Synchronous Generators ◽  
State Equations ◽  
Starting Point ◽  
Short Circuits

Although of a great extent in time, the research works directed at studying transients in synchronous generators have not yet provided fully sufficient comparative studies in respect to sudden short circuits of the machine. The present paper puts forward novel and comprehensive process models for dynamic simulation of short circuit faults of initially unloaded synchronous generators, using the generalizedd-q-0 mathematical model as starting point in derivation. Distinct from the time-domain analysis, the technique proposed here allows an effective comparative overview by employing a specialized procedure to perform repeated time-domain simulations accompanied by peak values recording for the various circumstances. The time consuming matrix numerical inversion at each step of integration, usually performed when selecting currents as state variables, is eliminated by advancing the process models in a convenient split matrix form that allows the symbolic processing. Also, the computational efficiency is being increased by introducing a set of auxiliary variables common to different state equations. The models derivation is carried out without altering the structural equations of the generalizedd-q-0 mathematical model of synchronous generators whilst the simulation results are both compared and discussed in detail.

scholarly journals Systèmes vivants : Lois locales et globales, invariance d'échelle

2020 ◽  
Vol 4 ◽  
pp. 195-218
Author(s):  
Pierre Bricage
Keyword(s):  
Power Law ◽  
Degrees Of Freedom ◽  
Living System ◽  
Living Systems ◽  
Global Level ◽  
Duration Time ◽  
Constructal Law ◽  
Local Actors ◽  
Qualitative Characteristics ◽  
Organizing Principles

To survive that is 'to eat and not to be eaten', to live on [9, 11]. Any living system [10], to survive and live on [9], whatever is its spatial [28] and temporal [23, 29, 35] level of organization, owns 7 invariant qualitative characteristics (degrees of freedom) [19]. Any alive system is formed by embedding and juxtapositions [17] of pre-existing systems [22]. How are the local quantitative laws, of their spatial-temporal structuring and functioning, associated with these qualitative characteristics independently from the dimensional scales? How are they independent/dependent from the new global level of organization and the local situations of emergence? How do the local actors become mutually integrated into their global whole? And reversely (systemic constructal law [4]), why and how is the global whole reciprocally integrating the local parceners [18, 20]? At every level of organization, the evolution of the living systems obeys 5 organizing principles of emergence [33] and the space (the volume of the adult system VA) and the duration (time of generation tg) are linked through a power law (generalized Kepler's 3rd law like VA2 = C.tg3), a law of growth (figure 3) and exchange (figure 4). As all the sub-systems which live in it, the whole Universe is living in an ecoexotope that it can share with other Universes.

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