Cellular Scaling Rules of Insectivore Brains
Sarko, Diana K.; Catania, Kenneth C.; Leitch, Duncan B.; Kaas, Jon H.; Herculano-Houzel, Suzana
2009-01-01
Insectivores represent extremes in mammalian body size and brain size, retaining various “primitive” morphological characteristics, and some species of Insectivora are thought to share similarities with small-bodied ancestral eutherians. This raises the possibility that insectivore brains differ from other taxa, including rodents and primates, in cellular scaling properties. Here we examine the cellular scaling rules for insectivore brains and demonstrate that insectivore scaling rules overla...
Cellular scaling rules of insectivore brains
Sarko, Diana K.; Catania, Kenneth C.; Leitch, Duncan B.; Kaas, Jon H.; Suzana Herculano-Houzel
2009-01-01
Insectivores represent extremes in mammalian body size and brain size, retaining various “primitive” morphological characteristics, and some species of Insectivora are thought to share similarities with small-bodied ancestral eutherians. This raises the possibility that insectivore brains differ from other taxa, including rodents and primates, in cellular scaling properties. Here we examine the cellular scaling rules for insectivore brains and demonstrate that insectivore scaling ...
Cellular scaling rules for primate brains
Herculano-Houzel, Suzana; Collins, Christine E.; Wong, Peiyan; Kaas, Jon H.
2007-01-01
Primates are usually found to have richer behavioral repertoires and better cognitive abilities than rodents of similar brain size. This finding raises the possibility that primate brains differ from rodent brains in their cellular composition. Here we examine the cellular scaling rules for primate brains and show that brain size increases approximately isometrically as a function of cell numbers, such that an 11× larger brain is built with 10× more neurons and ≈12× more nonneuronal cells of ...
Cellular scaling rules of insectivore brains
Diana K Sarko
2009-06-01
Full Text Available Insectivores represent extremes in mammalian body size and brain size, retaining various “primitive” morphological characteristics, and some species of Insectivora are thought to share similarities with small-bodied ancestral eutherians. This raises the possibility that insectivore brains differ from other taxa, including rodents and primates, in cellular scaling properties. Here we examine the cellular scaling rules for insectivore brains and demonstrate that insectivore scaling rules overlap somewhat with those for rodents and primates such that the insectivore cortex shares scaling rules with rodents (increasing faster in size than in numbers of neurons, but the insectivore cerebellum shares scaling rules with primates (increasing isometrically. Brain structures pooled as “remaining areas” appear to scale similarly across all three mammalian orders with respect to numbers of neurons, and the numbers of non-neurons appear to scale similarly across all brain structures for all three orders. Therefore, common scaling rules exist, to different extents, between insectivore, rodent and primate brain regions, and it is hypothesized that insectivores represent the common aspects of each order. The olfactory bulbs of insectivores, however, offer a noteworthy exception in that neuronal density increases linearly with increasing structure mass. This implies that the average neuronal cell size decreases with increasing olfactory bulb mass in order to accommodate greater neuronal density, and represents the first documentation of a brain structure gaining neurons at a greater rate than mass. This might allow insectivore brains to concentrate more neurons within the olfactory bulbs without a prohibitively large and metabolically costly increase in structure mass.
Cellular scaling rules for the brain of afrotherians
Kleber eNeves; Fernanda eMeireles Ferreira; Fernanda eTovar-Moll; Nadine eGravett; Bennett, Nigel C.; Consolate eKaswera; Emmanuel eGilissen; Paul eManger; Suzana eHerculano-Houzel
2014-01-01
Quantitative analysis of the cellular composition of rodent, primate and eulipotyphlan brains has shown that nonneuronal scaling rules are similar across these mammalian orders that diverged about 95 million years ago, and therefore appear to be conserved in evolution, while neuronal scaling rules appear to be free to vary in evolution in a clade-specific manner. Here we analyze the cellular scaling rules that apply to the brain of afrotherians, believed to be the first clade to radiate from ...
Cellular scaling rules for the brain of afrotherians
Neves, Kleber; Ferreira, Fernanda M.; Tovar-Moll, Fernanda; Gravett, Nadine; Bennett, Nigel C.; Kaswera, Consolate; Gilissen, Emmanuel; Manger, Paul R.; Herculano-Houzel, Suzana
2014-01-01
Quantitative analysis of the cellular composition of rodent, primate and eulipotyphlan brains has shown that non-neuronal scaling rules are similar across these mammalian orders that diverged about 95 million years ago, and therefore appear to be conserved in evolution, while neuronal scaling rules appear to be free to vary in evolution in a clade-specific manner. Here we analyze the cellular scaling rules that apply to the brain of afrotherians, believed to be the first clade to radiate from...
Cellular Scaling Rules for Primate Spinal Cords
Burish, Mark J.; Peebles, J. Klint; Baldwin, Mary K.; Tavares, Luciano; Kaas, Jon H.; Herculano-Houzel, Suzana
2010-01-01
The spinal cord can be considered a major sensorimotor interface between the body and the brain. How does the spinal cord scale with body and brain mass, and how are its numbers of neurons related to the number of neurons in the brain across species of different body and brain sizes? Here we determine the cellular composition of the spinal cord in eight primate species and find that its number of neurons varies as a linear function of cord length, and accompanies body mass raised to an expone...
Cellular scaling rules for the brain of afrotherians
Neves, Kleber; Ferreira, Fernanda M.; Tovar-Moll, Fernanda; Gravett, Nadine; Bennett, Nigel C.; Kaswera, Consolate; Gilissen, Emmanuel; Manger, Paul R.; Herculano-Houzel, Suzana
2014-01-01
Quantitative analysis of the cellular composition of rodent, primate and eulipotyphlan brains has shown that non-neuronal scaling rules are similar across these mammalian orders that diverged about 95 million years ago, and therefore appear to be conserved in evolution, while neuronal scaling rules appear to be free to vary in evolution in a clade-specific manner. Here we analyze the cellular scaling rules that apply to the brain of afrotherians, believed to be the first clade to radiate from the common eutherian ancestor. We find that afrotherians share non-neuronal scaling rules with rodents, primates and eulipotyphlans, as well as the coordinated scaling of numbers of neurons in the cerebral cortex and cerebellum. Afrotherians share with rodents and eulipotyphlans, but not with primates, the scaling of number of neurons in the cortex and in the cerebellum as a function of the number of neurons in the rest of the brain. Afrotheria also share with rodents and eulipotyphlans the neuronal scaling rules that apply to the cerebral cortex. Afrotherians share with rodents, but not with eulipotyphlans nor primates, the neuronal scaling rules that apply to the cerebellum. Importantly, the scaling of the folding index of the cerebral cortex with the number of neurons in the cerebral cortex is not shared by either afrotherians, rodents, or primates. The sharing of some neuronal scaling rules between afrotherians and rodents, and of some additional features with eulipotyphlans and primates, raise the interesting possibility that these shared characteristics applied to the common eutherian ancestor. In turn, the clade-specific characteristics that relate to the distribution of neurons along the surface of the cerebral cortex and to its degree of gyrification suggest that these characteristics compose an evolutionarily plastic suite of features that may have defined and distinguished mammalian groups in evolution. PMID:24596544
A unique cellular scaling rule in the avian auditory system.
Corfield, Jeremy R; Long, Brendan; Krilow, Justin M; Wylie, Douglas R; Iwaniuk, Andrew N
2016-06-01
Although it is clear that neural structures scale with body size, the mechanisms of this relationship are not well understood. Several recent studies have shown that the relationship between neuron numbers and brain (or brain region) size are not only different across mammalian orders, but also across auditory and visual regions within the same brains. Among birds, similar cellular scaling rules have not been examined in any detail. Here, we examine the scaling of auditory structures in birds and show that the scaling rules that have been established in the mammalian auditory pathway do not necessarily apply to birds. In galliforms, neuronal densities decrease with increasing brain size, suggesting that auditory brainstem structures increase in size faster than neurons are added; smaller brains have relatively more neurons than larger brains. The cellular scaling rules that apply to auditory brainstem structures in galliforms are, therefore, different to that found in primate auditory pathway. It is likely that the factors driving this difference are associated with the anatomical specializations required for sound perception in birds, although there is a decoupling of neuron numbers in brain structures and hair cell numbers in the basilar papilla. This study provides significant insight into the allometric scaling of neural structures in birds and improves our understanding of the rules that govern neural scaling across vertebrates. PMID:26002617
Cellular scaling rules for the brain of Artiodactyla include a highly folded cortex with few neurons
Rodrigo eSiqueira Kazu; Jose eMaldonado; Bruno eMota; Paul eManger; Suzana eHerculano-Houzel
2014-01-01
Quantitative analysis of the cellular composition of rodent, primate, insectivore, and afrotherian brains has shown that non-neuronal scaling rules are similar across these mammalian orders that diverged about 95 million years ago, and therefore appear to be conserved in evolution, while neuronal scaling rules appear to be free to vary in a clade-specific manner. Here we analyze the cellular scaling rules that apply to the brain of artiodactyls, a group within the order Cetartiodactyla, belie...
Cellular scaling rules for the brain of Artiodactyla include a highly folded cortex with few neurons
Rodrigo eSiqueira Kazu
2014-11-01
Full Text Available Quantitative analysis of the cellular composition of rodent, primate, insectivore and afrotherian brains has shown that nonneuronal scaling rules are similar across these mammalian orders that diverged about 95 million years ago, and therefore appear to be conserved in evolution, while neuronal scaling rules appear to be free to vary in a clade-specific manner. Here we analyze the cellular scaling rules that apply to the brain of artiodactyls, a group within the order Cetartiodactyla, believed to be a relatively recent radiation from the common Eutherian ancestor. We find that artiodactyls share nonneuronal scaling rules with all groups analyzed previously. Artiodactyls share with afrotherians and rodents, but not with primates, the neuronal scaling rules that apply to the cerebral cortex and cerebellum. The neuronal scaling rules that apply to the remaining brain areas are however distinct in artiodactyls. Importantly, we show that the folding index of the cerebral cortex scales with the number of neurons in the cerebral cortex in distinct fashions across artiodactyls, afrotherians, rodents, and primates, such that the artiodactyl cerebral cortex is more convoluted than primate cortices of similar numbers of neurons. Our findings suggest that the scaling rules found to be shared across modern afrotherians, glires and artiodactyls applied to the common Eutherian ancestor, such as the relationship between the mass of the cerebral cortex as a whole and its number of neurons. In turn, the distribution of neurons along the surface of the cerebral cortex, which is related to its degree of gyrification, appears to be a clade-specific characteristic. If the neuronal scaling rules for artiodactyls extend to all cetartiodactyls, we predict that the large cerebral cortex of cetaceans will still have fewer neurons than the human cerebral cortex.
Herculano-Houzel, Suzana; Kaas, Jon H
2011-01-01
Gorillas and orangutans are primates at least as large as humans, but their brains amount to about one third of the size of the human brain. This discrepancy has been used as evidence that the human brain is about 3 times larger than it should be for a primate species of its body size. In contrast to the view that the human brain is special in its size, we have suggested that it is the great apes that might have evolved bodies that are unusually large, on the basis of our recent finding that the cellular composition of the human brain matches that expected for a primate brain of its size, making the human brain a linearly scaled-up primate brain in its number of cells. To investigate whether the brain of great apes also conforms to the primate cellular scaling rules identified previously, we determine the numbers of neuronal and other cells that compose the orangutan and gorilla cerebella, use these numbers to calculate the size of the brain and of the cerebral cortex expected for these species, and show that these match the sizes described in the literature. Our results suggest that the brains of great apes also scale linearly in their numbers of neurons like other primate brains, including humans. The conformity of great apes and humans to the linear cellular scaling rules that apply to other primates that diverged earlier in primate evolution indicates that prehistoric Homo species as well as other hominins must have had brains that conformed to the same scaling rules, irrespective of their body size. We then used those scaling rules and published estimated brain volumes for various hominin species to predict the numbers of neurons that composed their brains. We predict that Homo heidelbergensis and Homo neanderthalensis had brains with approximately 80 billion neurons, within the range of variation found in modern Homo sapiens. We propose that while the cellular scaling rules that apply to the primate brain have remained stable in hominin evolution (since they
Cellular Scaling Rules for the Brains of an Extended Number of Primate Species
Gabi, Mariana; Collins, Christine E.; Wong, Peiyan; Torres, Laila B.; Kaas, Jon H.; Herculano-Houzel, Suzana
2010-01-01
What are the rules relating the size of the brain and its structures to the number of cells that compose them and their average sizes? We have shown previously that the cerebral cortex, cerebellum and the remaining brain structures increase in size as a linear function of their numbers of neurons and non-neuronal cells across 6 species of primates. Here we describe that the cellular composition of the same brain structures of 5 other primate species, as well as humans, conform to the scaling ...
Validity of the Cauchy-Born rule applied to discrete cellular-scale models of biological tissues
Davit, Y.
2013-04-30
The development of new models of biological tissues that consider cells in a discrete manner is becoming increasingly popular as an alternative to continuum methods based on partial differential equations, although formal relationships between the discrete and continuum frameworks remain to be established. For crystal mechanics, the discrete-to-continuum bridge is often made by assuming that local atom displacements can be mapped homogeneously from the mesoscale deformation gradient, an assumption known as the Cauchy-Born rule (CBR). Although the CBR does not hold exactly for noncrystalline materials, it may still be used as a first-order approximation for analytic calculations of effective stresses or strain energies. In this work, our goal is to investigate numerically the applicability of the CBR to two-dimensional cellular-scale models by assessing the mechanical behavior of model biological tissues, including crystalline (honeycomb) and noncrystalline reference states. The numerical procedure involves applying an affine deformation to the boundary cells and computing the quasistatic position of internal cells. The position of internal cells is then compared with the prediction of the CBR and an average deviation is calculated in the strain domain. For center-based cell models, we show that the CBR holds exactly when the deformation gradient is relatively small and the reference stress-free configuration is defined by a honeycomb lattice. We show further that the CBR may be used approximately when the reference state is perturbed from the honeycomb configuration. By contrast, for vertex-based cell models, a similar analysis reveals that the CBR does not provide a good representation of the tissue mechanics, even when the reference configuration is defined by a honeycomb lattice. The paper concludes with a discussion of the implications of these results for concurrent discrete and continuous modeling, adaptation of atom-to-continuum techniques to biological
Cellular Automata Rules and Linear Numbers
Nayak, Birendra Kumar; Sahoo, Sudhakar; Biswal, Sagarika
2012-01-01
In this paper, linear Cellular Automta (CA) rules are recursively generated using a binary tree rooted at "0". Some mathematical results on linear as well as non-linear CA rules are derived. Integers associated with linear CA rules are defined as linear numbers and the properties of these linear numbers are studied.
Abkarian, Manouk; Faivre, Magalie; Horton, Renita; Smistrup, Kristian; Best-Popescu, Catherine A; Stone, Howard A.
2008-01-01
Microfluidic tools are providing many new insights into the chemical, physical and physicochemical responses of cells. Both suspension-level and single-cell measurements have been studied. We review our studies of these kinds of problems for red blood cells with particular focus on the shapes of ...... mechanical effects on suspended cells can be studied systematically in small devices, and how these features can be exploited to develop methods for characterizing physicochemical responses and possibly for the diagnosis of cellular-scale changes to environmental factors....
Cellular automata with majority rule on evolving network
Makowiec, Danuta
2004-01-01
The cellular automata discrete dynamical system is considered as the two-stage process: the majority rule for the change in the automata state and the rule for the change in topological relations between automata. The influence of changing topology to the cooperative phenomena, namely zero-temperature ferromagnetic phase transition, is observed.
EVOLUTION COMPLEXITY OF THEELEMENTARY CELLULAR AUTOMATON OF RULE 22
WangYi; JiangZhisong
2002-01-01
Cellular automata are the discrete dynamical systems of simple construction but with complex and varied behaviors. In this paper, the elementary cellular automaton of rule 22 is studied by the tools of formal language theory and symbolic dynamics. Its temporal evolution orbits are coarse-grained into evolution sequences and the evolution languages are defined. It is proved that for every n≥2 its width n evolution language is not regular.
Interval maps associated to the cellular automaton rule 184
We associate to the cellular automaton elementary rule 184 an interval map defined in [0,1]. We show that this interval map is characterized by a functional equation which depends directly on the local rule and also depends on the choice to represent numbers in base 2. The functional equation is the analytical expression of the interval map self-similarity. We also compute a family of transition matrices which characterizes the effect of the interval map on a family of partitions of the interval [0,1]. We show how the family of matrices can be built with a recursive algorithm which depends on the local rule.
Cellular scaling rules for rodent brains
Herculano-Houzel, Suzana; Mota, Bruno; Lent, Roberto
2006-01-01
How do cell number and size determine brain size? Here, we show that, in the order Rodentia, increased size of the cerebral cortex, cerebellum, and remaining areas across six species is achieved through greater numbers of neurons of larger size, and much greater numbers of nonneuronal cells of roughly invariant size, such that the ratio between total neuronal and nonneuronal mass remains constant across species. Although relative cerebellar size remains stable among rodents, the number of cer...
Probabilistic initial value problem for cellular automaton rule 172
Fuks, Henryk
2010-01-01
We present a method of solving of the probabilistic initial value problem for cellular automata (CA) using CA rule 172 as an example. For a disordered initial condition on an infinite lattice, we derive exact expressions for the density of ones at arbitrary time step. In order to do this, we analyze topological structure of preimage trees of finite strings of length 3. Level sets of these trees can be enumerated directly using classical combinatorial methods, yielding expressions for the numb...
Threshold-Range Scaling of Excitable Cellular Automata
Fisch, R; Griffeath, D; Fisch, Robert; Gravner, Janko; Griffeath, David
1993-01-01
Each cell of a two-dimensional lattice is painted one of k colors, arranged in a "color wheel." The colors advance (0 to k-1 mod k) either automatically or by contact with at least a threshold number of successor colors in a prescribed local neighborhood. Discrete-time parallel systems of this sort in which color 0 updates by contact and the rest update automatically are called Greenberg-Hastings (GH) rules. A system in which all colors update by contact is called a cyclic cellular automaton (CCA). Started from appropriate initial conditions these models generate periodic traveling waves. Started from random configurations the same rules exhibit complex self-organization, typically characterized by nucleation of locally periodic "ram's horns" or spirals. Corresponding random processes give rise to a variety of "forest fire" equilibria that display large-scale stochastic wave fronts. This article describes a framework, theoretically based, but relying on extensive interactive computer graphics experimentation,...
Color Graphs: An Efficient Model For Two-Dimensional Cellular Automata Linear Rules
Nayak, Birendra Kumar; Rout, Sushant Kumar
2008-01-01
Two-dimensional nine neighbor hood rectangular Cellular Automata rules can be modeled using many different techniques like Rule matrices, State Transition Diagrams, Boolean functions, Algebraic Normal Form etc. In this paper, a new model is introduced using color graphs to model all the 512 linear rules. The graph theoretic properties therefore studied in this paper simplifies the analysis of all linear rules in comparison with other ways of its study.
Neighborhood Selection and Rules Identification for Cellular Automata: A Rough Sets Approach
Placzek, Bartlomiej
2014-01-01
In this paper a method is proposed which uses data mining techniques based on rough sets theory to select neighborhood and determine update rule for cellular automata (CA). According to the proposed approach, neighborhood is detected by reducts calculations and a rule-learning algorithm is applied to induce a set of decision rules that define the evolution of CA. Experiments were performed with use of synthetic as well as real-world data sets. The results show that the introduced method allow...
Martín Del Rey, A.; Rodríguez Sánchez, G.
2015-03-01
The study of the reversibility of elementary cellular automata with rule number 150 over the finite state set 𝔽p and endowed with periodic boundary conditions is done. The dynamic of such discrete dynamical systems is characterized by means of characteristic circulant matrices, and their analysis allows us to state that the reversibility depends on the number of cells of the cellular space and to explicitly compute the corresponding inverse cellular automata.
Incorporating scale invariance into the cellular associative neural network
Burles, Nathan; O'Keefe, Simon; Austin, James
2014-01-01
This paper describes an improvement to the Cellular Associative Neural Network, an architecture based on the distributed model of a cellular automaton, allowing it to perform scale invariant pattern matching. The use of tensor products and superposition of patterns allows the system to recall patterns at multiple resolutions simultaneously. Our experimental results show that the architecture is capable of scale invariant pattern matching, but that further investigation is needed to reduce the...
Evolution from Cellular to Social Scales
Skjeltorp, Arne T
2008-01-01
Evolution is a critical challenge for many areas of science, technology and development of society. The book reviews general evolutionary facts such as origin of life and evolution of the genome and clues to evolution through simple systems. Emerging areas of science such as "systems biology" and "bio-complexity" are founded on the idea that phenomena need to be understood in the context of highly interactive processes operating at different levels and on different scales. This is where physics meets complexity in nature, and where we must begin to learn about complexity if we are to understand it. Similarly, there is an increasingly urgent need to understand and predict the evolutionary behavior of highly interacting man-made systems, in areas such as communications and transport, which permeate the modern world. The same applies to the evolution of human networks such as social, political and financial systems, where technology has tended to vastly increase both the complexity and speed of interaction, whic...
Two-lane traffic rules for cellular automata: A systematic approach
Nagel, K. [Los Alamos National Lab., NM (United States)]|[Forschungszentrum Juelich (Germany). Hoechsteleistungsrechenzentrum HLRZ; Wolf, D.E. [Forschungszentrum Juelich (Germany). Hoechstleistungsrechenzentrum HLRZ]|[Gerhard-Mercator-Univ., Duisburg (Germany). Theoretische Physik; Wagner, P. [Univ. zu Koeln (Germany). Zentrum Fuer Paralleles Rechnen]|[Deutsche Forschungsanstalt fuer Luft- und Raumfahrt, Koeln (Germany); Simon, P. [Los Alamos National Lab., NM (United States)
1997-11-05
Microscopic modeling of multi-lane traffic is usually done by applying heuristic lane changing rules, and often with unsatisfying results. Recently, a cellular automation model for two-lane traffic was able to overcome some of these problems and to produce a correct density inversion at densities somewhat below the maximum flow density. In this paper, the authors summarize different approaches to lane changing and their results, and propose a general scheme, according to which realistic lane changing rules can be developed. They test this scheme by applying it to several different lane changing rules, which, in spite of their differences, generate similar and realistic results. The authors thus conclude that, for producing realistic results, the logical structure of the lane changing rules, as proposed here, is at least as important as the microscopic details of the rules.
Time scale of diffusion in molecular and cellular biology
Holcman, D.; Schuss, Z.
2014-05-01
Diffusion is the driver of critical biological processes in cellular and molecular biology. The diverse temporal scales of cellular function are determined by vastly diverse spatial scales in most biophysical processes. The latter are due, among others, to small binding sites inside or on the cell membrane or to narrow passages between large cellular compartments. The great disparity in scales is at the root of the difficulty in quantifying cell function from molecular dynamics and from simulations. The coarse-grained time scale of cellular function is determined from molecular diffusion by the mean first passage time of molecular Brownian motion to a small targets or through narrow passages. The narrow escape theory (NET) concerns this issue. The NET is ubiquitous in molecular and cellular biology and is manifested, among others, in chemical reactions, in the calculation of the effective diffusion coefficient of receptors diffusing on a neuronal cell membrane strewn with obstacles, in the quantification of the early steps of viral trafficking, in the regulation of diffusion between the mother and daughter cells during cell division, and many other cases. Brownian trajectories can represent the motion of a molecule, a protein, an ion in solution, a receptor in a cell or on its membrane, and many other biochemical processes. The small target can represent a binding site or an ionic channel, a hidden active site embedded in a complex protein structure, a receptor for a neurotransmitter on the membrane of a neuron, and so on. The mean time to attach to a receptor or activator determines diffusion fluxes that are key regulators of cell function. This review describes physical models of various subcellular microdomains, in which the NET coarse-grains the molecular scale to a higher cellular-level, thus clarifying the role of cell geometry in determining subcellular function.
Van De Wiel, Marco J.; Coulthard, Tom J.; Macklin, Mark G.; Lewin, John
2007-10-01
We introduce a new computational model designed to simulate and investigate reach-scale alluvial dynamics within a landscape evolution model. The model is based on the cellular automaton concept, whereby the continued iteration of a series of local process 'rules' governs the behaviour of the entire system. The model is a modified version of the CAESAR landscape evolution model, which applies a suite of physically based rules to simulate the entrainment, transport and deposition of sediments. The CAESAR model has been altered to improve the representation of hydraulic and geomorphic processes in an alluvial environment. In-channel and overbank flow, sediment entrainment and deposition, suspended load and bed load transport, lateral erosion and bank failure have all been represented as local cellular automaton rules. Although these rules are relatively simple and straightforward, their combined and repeatedly iterated effect is such that complex, non-linear geomorphological response can be simulated within the model. Examples of such larger-scale, emergent responses include channel incision and aggradation, terrace formation, channel migration and river meandering, formation of meander cutoffs, and transitions between braided and single-thread channel patterns. In the current study, the model is illustrated on a reach of the River Teifi, near Lampeter, Wales, UK.
Cellular automata simulation of nanometre-scale MOSFETs
Saraniti, M.; Zandler, G.; Formicone, G.; Wigger, S.; Goodnick, S.
1998-08-01
We present systematic theoretical cellular automata studies of vertically grown, nanometre-scale, MOSFETs. The predicted drain characteristics and output conductance are in excellent agreement with experimental data from fabricated devices. The inclusion of an inhomogeneous p-doping profiles along the channel is investigated, which is shown to improve current saturation and therefore allows the reduction of the device dimensions.
Crossover scaling in the Domany-Kinzel cellular automaton
Lubeck, S.
2006-01-01
We consider numerically the crossover scaling behavior from the directed percolation universality class to the compact directed percolation universality class within the one-dimensional Domany-Kinzel cellular automaton. Our results are compared to those of a recently performed field theoretical approach. In particular, the value of the crossover exponent phi=2 is confirmed.
A quantitative approach to nonlinear IC process design rule scaling
Gold, Spencer Montgomery
As minimum dimensions in integrated circuit technologies are reduced beyond 0.1 m m, linear process scaling becomes more difficult and costly. Exponentially rising manufacturing facility and process scaling costs can be better managed by performing nonlinear process shrinks. Nonlinear scaling allows the horizontal design rules to be reduced by different factors according to their ability to provide area and performance improvement in a cost effective manner. This thesis describes a methodology and CAD tools for use in selecting nonlinear design rule reduction ratios that make effective tradeoffs between die cost and performance. The cost effectiveness of nonlinear scaling is demonstrated for a complementary GaAs (CGaAsTM) process. CGaAs is a young technology with coarse design rules that would benefit significantly from a nonlinear shrink. The cost/benefit analysis for scaling the design rules is based on a process-independent optimizing SRAM compiler which was developed as part of this work. The methodology for nonlinear scaling includes identifying the rules which have the greatest impact on circuit area and analyzing the area and performance improvements as these rules are scaled through a range of practical scale factors. Benefit data (product of power and delay improvement ratios) is then combined with die cost estimates at each step to yield the cost/benefit ratio, a quantitative metric for design rule reduction. The slopes and inflection points of cost/benefit vs. scale factor plots guide process engineers in selecting reduction ratios for the various design rules. This procedure should be repeated, using the results of one pass as the starting point for the next. The cost/benefit analysis methodology compares embedded static RAMs that are generated by the PUMA process-independent SRAM compiler. This compiler, which is based on Duet's MasterPortTM layout compactor, can create optimized SRAM cell libraries for any complementary technology. It is capable of
Colony-Level Differences in the Scaling Rules Governing Wood Ant Compound Eye Structure.
Perl, Craig D; Niven, Jeremy E
2016-01-01
Differential organ growth during development is essential for adults to maintain the correct proportions and achieve their characteristic shape. Organs scale with body size, a process known as allometry that has been studied extensively in a range of organisms. Such scaling rules, typically studied from a limited sample, are assumed to apply to all members of a population and/or species. Here we study scaling in the compound eyes of workers of the wood ant, Formica rufa, from different colonies within a single population. Workers' eye area increased with body size in all the colonies showing a negative allometry. However, both the slope and intercept of some allometric scaling relationships differed significantly among colonies. Moreover, though mean facet diameter and facet number increased with body size, some colonies primarily increased facet number whereas others increased facet diameter, showing that the cellular level processes underlying organ scaling differed among colonies. Thus, the rules that govern scaling at the organ and cellular levels can differ even within a single population. PMID:27068571
New approach to scaling rules for stellar and planetary dynamos
Barrois, Bertrand
2016-01-01
Glorified dimensional analysis is used to derive scaling rules for internal and external magnetic field strengths and various time scales. Naive dimensional analysis is inconclusive because of multiple time scales, but physical arguments serve to weed out irrelevant parameters. Time scales can be derived from linearized instability analysis instead of ill-founded assumptions of Magnetic-Archimedean-Coriolis (MAC) balance. Further relationships can be derived from high-level models of coupled main field components and differential rotation. The ratios of the external dipole field to internal magnetic fields and of differential to overall rotation depend on details of the dynamo mechanism.
Size structure, not metabolic scaling rules, determines fisheries reference points
Andersen, Ken Haste; Beyer, Jan
2015-01-01
that even though small species have a higher productivity than large species their resilience towards fishing is lower than expected from metabolic scaling rules. Further, we show that the fishing mortality leading to maximum yield per recruit is an ill-suited reference point. The theory can be used to...... empirical relations is lacking. Here, we combine life-history invariants, metabolic scaling and size-spectrum theory to develop a general size- and trait-based theory for demography and recruitment of exploited fish stocks. Important concepts are physiological or metabolic scaled mortalities and flux of...... that larger species have a higher egg production per recruit than small species. This means that density dependence is stronger for large than for small species and has the consequence that fisheries reference points that incorporate recruitment do not obey metabolic scaling rules. This result implies...
Sub-classes and evolution stability of Wolfram's classesin the total-rule cellular automata
YAN Guangwu; TIAN Feng; DONG Yinfeng
2004-01-01
In this paper, we propose a concept of sub-classes and its evolution stability for the Wolfram's classes. Firstly, we obtain the sub-classes of the Wolfram's class IV, gene-piece of these sub-classes and their existing circumstance. Secondly, we introduce a new concept, the evolution stability, for the Wolfram's classes and sub-classes of Wolfram's class IV. Lastly, we find that Wolfram's classes I, II, and III have the evolution stability, but sub-classes of the Wolfram's class IV have not the evolution stability for the total rule cellular automata.
Scaling rules for critical current density in anisotropic biaxial superconductors
Li, Yingxu; Kang, Guozheng; Gao, Yuanwen
2016-06-01
Recent researches highlight the additional anisotropic crystallographic axis within the superconducting plane of high temperature superconductors (HTS), demonstrating the superconducting anisotropy of HTS is better understood in the biaxial frame than the previous uniaxial coordinates within the superconducting layer. To quantitatively evaluate the anisotropy of flux pinning and critical current density in HTS, we extend the scaling rule for single-vortex collective pinning in uniaxial superconductors to account for flux-bundle collective pinning in biaxial superconductors. The scaling results show that in a system of random uncorrected point defects, the field dependence of the critical current density is described by a unified function with the scaled magnetic field of the isotropic superconductor. The obtained angular dependence of the critical current density depicts the main features of experimental observations, considering possible corrections due to the strong-pinning interaction.
From cellular to tissue scales by asymptotic limits of thermostatted kinetic models
Bianca, Carlo; Dogbe, Christian; Lemarchand, Annie
2016-02-01
Tumor growth strictly depends on the interactions occurring at the cellular scale. In order to obtain the linking between the dynamics described at tissue and cellular scales, asymptotic methods have been employed, consisting in deriving tissue equations by suitable limits of mesoscopic models. In this paper, the evolution at the cellular scale is described by thermostatted kinetic theory that include conservative, nonconservative (proliferation, destruction and mutations), stochastic terms, and the role of external agents. The dynamics at the tissue scale (cell-density evolution) is obtained by performing a low-field scaling and considering the related convergence of the rescaled framework when the scaling parameter goes to zero.
Brain structure and dynamics across scales: in search of rules.
Wang, Xiao-Jing; Kennedy, Henry
2016-04-01
Louis Henry Sullivan, the father of skyscrapers, famously stated 'Form ever follows function'. In this short review, we will focus on the relationship between form (structure) and function (dynamics) in the brain. We summarize recent advances on the quantification of directed- and weighted-mesoscopic connectivity of mammalian cortex, the exponential distance rule for mesoscopic and microscopic circuit wiring, a spatially embedded random model of inter-areal cortical networks, and a large-scale dynamical circuit model of money's cortex that gives rise to a hierarchy of timescales. These findings demonstrate that inter-areal cortical networks are dense (hence such concepts as 'small-world' need to be refined when applied to the brain), spatially dependent (therefore purely topological approach of graph theory has limited applicability) and heterogeneous (consequently cortical areas cannot be treated as identical 'nodes'). PMID:26868043
We study certain types of Cellular Automata (CA) viewed as an abstraction of large-scale Multi-Agent Systems (MAS). We argue that the classical CA model needs to be modified in several important respects, in order to become a relevant and sufficiently general model for the large-scale MAS, and so that thus generalized model can capture many important MAS properties at the level of agent ensembles and their long-term collective behavior patterns. We specifically focus on the issue of inter-agent communication in CA, and propose sequential cellular automata (SCA) as the first step, and genuinely Asynchronous Cellular Automata (ACA) as the ultimate deterministic CA-based abstract models for large-scale MAS made of simple reactive agents. We first formulate deterministic and nondeterministic versions of sequential CA, and then summarize some interesting configuration space properties (i.e., possible behaviors) of a restricted class of sequential CA. In particular, we compare and contrast those properties of sequential CA with the corresponding properties of the classical (that is, parallel and perfectly synchronous) CA with the same restricted class of update rules. We analytically demonstrate failure of the studied sequential CA models to simulate all possible behaviors of perfectly synchronous parallel CA, even for a very restricted class of non-linear totalistic node update rules. The lesson learned is that the interleaving semantics of concurrency, when applied to sequential CA, is not refined enough to adequately capture the perfect synchrony of parallel CA updates. Last but not least, we outline what would be an appropriate CA-like abstraction for large-scale distributed computing insofar as the inter-agent communication model is concerned, and in that context we propose genuinely asynchronous CA. (author)
Cellular Phone Towers, Published in 2006, 1:1200 (1in=100ft) scale, Farmer.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Field Observation information as of 2006. Data by this...
Cellular Phone Towers, Published in 1990, Smaller than 1:100000 scale, Pitt County GIS.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at Smaller than 1:100000 scale, was produced all or in part from Published Reports/Deeds information as of 1990. Data...
Women Rule: Potato Markets, Cellular Phones and Access to Information in the Bolivian Highlands
Amaya, N.; Alwang, Jeffrey
2011-01-01
In highland Bolivia, potato markets are widespread, and access to market information has entered the digital age. Information networks lubricated by ubiquitous cellular technologies are supplanting traditional means of information-gathering. We explore the impacts of access to cellular phones on market selection, use of social networks to acquire information, and gendered responsibilities within the potato market chain near Cochabamba. The entire family participates in potato production and m...
Full-Duplex Communications in Large-Scale Cellular Networks
AlAmmouri, Ahmad
2016-04-01
In-band full-duplex (FD) communications have been optimistically promoted to improve the spectrum utilization and efficiency. However, the penetration of FD communications to the cellular networks domain is challenging due to the imposed uplink/downlink interference. This thesis presents a tractable framework, based on stochastic geometry, to study FD communications in multi-tier cellular networks. Particularly, we assess the FD communications effect on the network performance and quantify the associated gains. The study proves the vulnerability of the uplink to the downlink interference and shows that the improved FD rate gains harvested in the downlink (up to 97%) comes at the expense of a significant degradation in the uplink rate (up to 94%). Therefore, we propose a novel fine-grained duplexing scheme, denoted as α-duplex scheme, which allows a partial overlap between the uplink and the downlink frequency bands. We derive the required conditions to harvest rate gains from the α-duplex scheme and show its superiority to both the FD and half-duplex (HD) schemes. In particular, we show that the α-duplex scheme provides a simultaneous improvement of 28% for the downlink rate and 56% for the uplink rate. We also show that the amount of the overlap can be optimized based on the network design objective. Moreover, backward compatibility is an essential ingredient for the success of new technologies. In the context of in-band FD communication, FD base stations (BSs) should support HD users\\' equipment (UEs) without sacrificing the foreseen FD gains. The results show that FD-UEs are not necessarily required to harvest rate gains from FD-BSs. In particular, the results show that adding FD-UEs to FD-BSs offers a maximum of 5% rate gain over FD-BSs and HD-UEs case, which is a marginal gain compared to the burden required to implement FD transceivers at the UEs\\' side. To this end, we shed light on practical scenarios where HD-UEs operation with FD-BSs outperforms the
Understanding Mobile Traffic Patterns of Large Scale Cellular Towers in Urban Environment
Wang, Huandong; Xu, Fengli; Li, Yong; Zhang, Pengyu; Jin, Depeng
2015-01-01
Understanding mobile traffic patterns of large scale cellular towers in urban environment is extremely valuable for Internet service providers, mobile users, and government managers of modern metropolis. This paper aims at extracting and modeling the traffic patterns of large scale towers deployed in a metropolitan city. To achieve this goal, we need to address several challenges, including lack of appropriate tools for processing large scale traffic measurement data, unknown traffic patterns...
van Raan, Anthony F. J.
2007-01-01
For the 100 largest European universities we studied the statistical properties of bibliometric indicators related to research performance, field citation density and journal impact. We find a size-dependent cumulative advantage for the impact of universities in terms of total number of citations. In previous work a similar scaling rule was found at the level of research groups. Therefore we conjecture that this scaling rule is a prevalent property of the science system. We observe that lower...
Mean value sum rules and test of scale breaking (in neutrino scattering)
Akama, K
1975-01-01
The author proposes sum rules which can be used for testing the scaling hypothesis and its powerlike breakdown in deep inelastic neutrino scattering. These sum rules are written in terms of the mean values of quantities determined solely by the outgoing leptons. By comparing with the latest CERN-Gargamelle data, they find that the Oth moment of structure function is still consistent with scaling. However, the 1st moment may have a scale breaking. In order to test such scale breaking more quantitatively, experimental determination of (E'/sup 2/), (v/sup 2/), (vE'), etc., is highly desirable in the near future. (15 refs).
SAS: Implementation of scaled association rules on spatial multidimensional quantitative dataset
M. N. Doja
2012-09-01
Full Text Available Mining spatial association rules is one of the most important branches in the field of Spatial Data Mining (SDM. Because of the complexity of spatial data, a traditional method in extracting spatial association rules is to transform spatial database into general transaction database. The Apriori algorithm is one of the most commonly used methods in mining association rules at present. But a shortcoming of the algorithm is that its performance on the large database is inefficient. The present paper proposed a new algorithm by extracting maximum frequent itemsets based on spatial multidimensional quantitative dataset. Algorithms for mining spatial association rules are similar to association rule mining except consideration of special data, the predicates generation and rule generation processes are based on Apriori. The proposed method (SAS Scaled Aprori on Spatial multidimensional quantitative dataset in the paper reduces the number of itemsets generated and also improves the execution time of the algorithm.
Rule Following and Rule Use in the Balance-Scale Task
Shultz, Thomas R.; Takane, Yoshio
2007-01-01
Quinlan et al. [Quinlan, p., van der Mass, H., Jansen, B., Booij, O., & Rendell, M. (this issue). Re-thinking stages of cognitive development: An appraisal of connectionist models of the balance scale task. "Cognition", doi:10.1016/j.cognition.2006.02.004] use Latent Class Analysis (LCA) to criticize a connectionist model of development on the…
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Published Reports/Deeds information as of 2010. It is...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Published Reports/Deeds information as of 2007. It is...
Scaling to Nanotechnology Limits with the PIMS Computer Architecture and a new Scaling Rule.
Debenedictis, Erik
2015-02-01
We describe a new approach to computing that moves towards the limits of nanotechnology using a newly formulated sc aling rule. This is in contrast to the current computer industry scali ng away from von Neumann's original computer at the rate of Moore's Law. We extend Moore's Law to 3D, which l eads generally to architectures that integrate logic and memory. To keep pow er dissipation cons tant through a 2D surface of the 3D structure requires using adiabatic principles. We call our newly proposed architecture Processor In Memory and Storage (PIMS). We propose a new computational model that integrates processing and memory into "tiles" that comprise logic, memory/storage, and communications functions. Since the programming model will be relatively stable as a system scales, programs repr esented by tiles could be executed in a PIMS system built with today's technology or could become the "schematic diagram" for implementation in an ultimate 3D nanotechnology of the future. We build a systems software approach that offers advantages over and above the technological and arch itectural advantages. Firs t, the algorithms may be more efficient in the conventional sens e of having fewer steps. Second, the algorithms may run with higher power efficiency per operation by being a better match for the adiabatic scaling ru le. The performance analysis based on demonstrated ideas in physical science suggests 80,000 x improvement in cost per operation for the (arguably) gene ral purpose function of emulating neurons in Deep Learning.
Feng, Song; Ollivier, Julien F; Swain, Peter S; Soyer, Orkun S
2015-10-30
Systems biologists aim to decipher the structure and dynamics of signaling and regulatory networks underpinning cellular responses; synthetic biologists can use this insight to alter existing networks or engineer de novo ones. Both tasks will benefit from an understanding of which structural and dynamic features of networks can emerge from evolutionary processes, through which intermediary steps these arise, and whether they embody general design principles. As natural evolution at the level of network dynamics is difficult to study, in silico evolution of network models can provide important insights. However, current tools used for in silico evolution of network dynamics are limited to ad hoc computer simulations and models. Here we introduce BioJazz, an extendable, user-friendly tool for simulating the evolution of dynamic biochemical networks. Unlike previous tools for in silico evolution, BioJazz allows for the evolution of cellular networks with unbounded complexity by combining rule-based modeling with an encoding of networks that is akin to a genome. We show that BioJazz can be used to implement biologically realistic selective pressures and allows exploration of the space of network architectures and dynamics that implement prescribed physiological functions. BioJazz is provided as an open-source tool to facilitate its further development and use. Source code and user manuals are available at: http://oss-lab.github.io/biojazz and http://osslab.lifesci.warwick.ac.uk/BioJazz.aspx. PMID:26101250
Performance of a small scale prototype of cellular honeycomb proportional chamber
Ahammed, Z; CERN. Geneva; Bhati, A K; Chattopadhyay, S; Dubey, A K; Dutta Mazumdar, M R; Mahapatra, D P; Ganti, M S; Nayak, T K; Singaraju, R N; Trivedi, M D; Viyogi, Y P; Aggarwal, M M
1999-01-01
Beam test results for the first small-scale prototype of a honeycomb cellular proportional chamber to be used in ALICE PMD are presented. The overall efficiency for MIP detection is found to be around 93%. The efficiency drops to about 75% at the corners of the hexagon. Improvement in design is suggested.
22号初等元胞自动机的演化复杂性%EVOLUTION COMPLEXITY OF THE ELEMENTARY CELLULAR AUTOMATON OF RULE 22
王益; 江志松
2002-01-01
Cellular automata are the discrete dynamical systems of simple construction but with complex and varied behaviors.In this paper,the elementary cellular automaton of rule 22 is studied by the tools of formal language theory and symbolic dynamics.Its temporal evolution orbits are coarse-grained into evolution sequences and the evolution languages are defined.It is proved that for every n≥2 its width n-evolution language is not regular.
Rafsanjani, Ahmad; Wittel, Falk K; Carmeliet, Jan
2015-01-01
The hygro-mechanical behavior of a hierarchical cellular material, i.e. growth rings of softwood is investigated using a two-scale micro-mechanics model based on a computational homogenization technique. The lower scale considers the individual wood cells of varying geometry and dimensions. Honeycomb unit cells with periodic boundary conditions are utilized to calculate the mechanical properties and swelling coefficients of wood cells. Using the cellular scale results, the anisotropy in mechanical and swelling behavior of a growth ring in transverse directions is investigated. Predicted results are found to be comparable to experimental data. It is found that the orthotropic swelling properties of the cell wall in thin-walled earlywood cells produce anisotropic swelling behavior while, in thick latewood cells, this anisotropy vanishes. The proposed approach provides the ability to consider the complex microstructure when predicting the effective mechanical and swelling properties of softwood.
Cheng, Y; Kekenes-Huskey, P; Hake, JE; Holst, MJ; McCammon, JA; Michailova, AP
2012-01-01
This article provides a brief review of multi-scale modeling at the molecular to cellular scale, with new results for heart muscle cells. A finite element-based simulation package (SMOL) was used to investigate the signaling transduction at molecular and sub-cellular scales (http://mccammon.ucsd.edu/smol/, http://FETK.org) by numerical solution of time-dependent Smoluchowski equations and a reaction-diffusion system. At the molecular scale, SMOL has yielded experimentally-validated estimates ...
A common origin for 3/4- and 2/3-power rules in metabolic scaling
Zhao, Jinkui
2015-01-01
A central debate in biology has been the allometric scaling of metabolic rate. Kleiber's observation that animals' basal metabolic rate scales to the 3/4-power of body mass (Kleiber's rule) has been the prevailing hypothesis in the last eight decades. Increasingly, more evidences are supporting the alternative 2/3-power scaling rule, especially for smaller animals. The 2/3-rule dates back to before Kleiber's time and was thought to originate from the surface to volume relationship in Euclidean geometry. In this study, we show that both the 3/4- and 2/3-scaling rules have in fact one common origin. They are governed by animals' nutrient supply networks-their vascular systems that obey Murray's law. Murray's law describes the branching pattern of energy optimized vascular network under laminar flow. It is generally regarded as being closely followed by blood vessels. Our analysis agrees with experimental observations and recent numerical analyses that showed a curvature in metabolic scaling. When applied to met...
Sum rules study and a scaling property of fragmentation mass yield curves
Information obtained in mass yield distributions produced in protons and heavy ions induced reactions has been analyzed with two model independent sum rules. The average number of fragments of different sizes produced in one collision has been extracted. A scaling law for the mass yield has been deduced. (orig.)
Multi-scale inference of interaction rules in animal groups using Bayesian model selection.
Richard P Mann
2012-01-01
Full Text Available Inference of interaction rules of animals moving in groups usually relies on an analysis of large scale system behaviour. Models are tuned through repeated simulation until they match the observed behaviour. More recent work has used the fine scale motions of animals to validate and fit the rules of interaction of animals in groups. Here, we use a Bayesian methodology to compare a variety of models to the collective motion of glass prawns (Paratya australiensis. We show that these exhibit a stereotypical 'phase transition', whereby an increase in density leads to the onset of collective motion in one direction. We fit models to this data, which range from: a mean-field model where all prawns interact globally; to a spatial Markovian model where prawns are self-propelled particles influenced only by the current positions and directions of their neighbours; up to non-Markovian models where prawns have 'memory' of previous interactions, integrating their experiences over time when deciding to change behaviour. We show that the mean-field model fits the large scale behaviour of the system, but does not capture fine scale rules of interaction, which are primarily mediated by physical contact. Conversely, the Markovian self-propelled particle model captures the fine scale rules of interaction but fails to reproduce global dynamics. The most sophisticated model, the non-Markovian model, provides a good match to the data at both the fine scale and in terms of reproducing global dynamics. We conclude that prawns' movements are influenced by not just the current direction of nearby conspecifics, but also those encountered in the recent past. Given the simplicity of prawns as a study system our research suggests that self-propelled particle models of collective motion should, if they are to be realistic at multiple biological scales, include memory of previous interactions and other non-Markovian effects.
Development and Validation of a Rule-Based Strength Scaling Method for Musculoskeletal Modelling
Oomen, Pieter; Annegarn, Janneke; Rasmussen, John;
2015-01-01
Rule based strength scaling is an easy, cheap and relatively accurate technique to personalize musculoskeletal (MS) models. This paper presents a new strength scaling approach for MS models and validates it by maximal voluntary contractions (MVC). A heterogeneous group of 63 healthy subjects...... performed maximal isometric knee extensions. A multiple linear regression analysis (MLR) resulted in an empirical strength scaling equation, accounting for age, mass, height, gender, segment masses and segment lengths. For validation purpose, 20 newly included healthy subjects performed a maximal isometric...... personalised modelling might require imaging to obtain more specific individual muscle characteristics, e.g. physiological cross sectional areas, optimal fibre length and pennation angles....
Herculano-Houzel, Suzana; Kaas, Jon H.
2011-01-01
Gorillas and orangutans are primates at least as large as humans, but their brains amount to about one third of the size of the human brain. This discrepancy has been used as evidence that the human brain is about 3 times larger than it should be for a primate species of its body size. In contrast to the view that the human brain is special in its size, we have suggested that it is the great apes that might have evolved bodies that are unusually large, on the basis of our recent finding that ...
Cellular Phone Towers, Cell Towers, Published in 2007, 1:1200 (1in=100ft) scale, Ness County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Orthoimagery information as of 2007. It is described as...
Cellular Phone Towers, Cell Towers, Published in 2010, 1:1200 (1in=100ft) scale, Liberty County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Orthoimagery information as of 2010. It is described as...
Cellular Phone Towers, Cell Towers, Published in 2007, 1:4800 (1in=400ft) scale, Harvey County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Orthoimagery information as of 2007. It is described as...
Cellular Phone Towers, cell sectors, Published in 2008, 1:2400 (1in=200ft) scale, Stanton County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Not Provided information as of 2008. It is described as...
Cellular Phone Towers, Cell Towers, Published in 2010, 1:1200 (1in=100ft) scale, Douglas County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Published Reports/Deeds information as of 2010. It is...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Not Provided information as of 2008. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at Smaller than 1:100000 scale, was produced all or in part from Published Reports/Deeds information as of 1995. Data...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Not Provided information as of 2008. It is described as...
Cellular Phone Towers, Published in 2006, 1:12000 (1in=1000ft) scale, Washington County GIS.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:12000 (1in=1000ft) scale, was produced all or in part from Field Observation information as of 2006. Data by this...
Cellular Phone Towers, Published in 2012, 1:1200 (1in=100ft) scale, Pierce County Wisconsin.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Other information as of 2012. Data by this publisher are...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Field Survey/GPS information as of 2001. It is described...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Field Observation information as of 2008. Data by this...
Cellular Phone Towers, Published in 2008, 1:4800 (1in=400ft) scale, White County Government.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Field Observation information as of 2008. Data by this...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Hardcopy Maps information as of Not Provided. Data by...
Cellular Phone Towers, Published in 2000, 1:1200 (1in=100ft) scale, Cumberland County Planning/GIS.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale as of 2000. Data by this publisher are often provided in State Plane coordinate system; in...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Other information as of 2006. Data by this publisher are...
Cellular Phone Towers, Published in 2011, 1:24000 (1in=2000ft) scale, St James Parish Government.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Hardcopy Maps information as of 2011. Data by this...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2010. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Published Reports/Deeds information as of 2006. It is...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Published Reports/Deeds information as of 2005. It is...
Cellular Phone Towers, Published in 2010, 1:1200 (1in=100ft) scale, City of Milton.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Published Reports/Deeds information as of 2010. Data by...
Cellular Phone Towers, Published in 2009, 1:2400 (1in=200ft) scale, City of Hays / Ellis County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Published Reports/Deeds information as of 2009. Data by...
Cellular Phone Towers, Cell Towers, Published in 2008, 1:2400 (1in=200ft) scale, Hamilton County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Not Provided information as of 2008. It is described as...
Cellular Phone Towers, Cell Sectors, Published in 2008, 1:2400 (1in=200ft) scale, Hamilton County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Not Provided information as of 2008. It is described as...
Cellular Phone Towers, Published in 2008, 1:4800 (1in=400ft) scale, Chautauqua County/Elk County.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Field Observation information as of 2008. Data by this...
Construction of Modular Hydrogel Sheets for Micropatterned Macro-scaled 3D Cellular Architecture.
Son, Jaejung; Bae, Chae Yun; Park, Je-Kyun
2016-01-01
Hydrogels can be patterned at the micro-scale using microfluidic or micropatterning technologies to provide an in vivo-like three-dimensional (3D) tissue geometry. The resulting 3D hydrogel-based cellular constructs have been introduced as an alternative to animal experiments for advanced biological studies, pharmacological assays and organ transplant applications. Although hydrogel-based particles and fibers can be easily fabricated, it is difficult to manipulate them for tissue reconstruction. In this video, we describe a fabrication method for micropatterned alginate hydrogel sheets, together with their assembly to form a macro-scale 3D cell culture system with a controlled cellular microenvironment. Using a mist form of the calcium gelling agent, thin hydrogel sheets are easily generated with a thickness in the range of 100 - 200 µm, and with precise micropatterns. Cells can then be cultured with the geometric guidance of the hydrogel sheets in freestanding conditions. Furthermore, the hydrogel sheets can be readily manipulated using a micropipette with an end-cut tip, and can be assembled into multi-layered structures by stacking them using a patterned polydimethylsiloxane (PDMS) frame. These modular hydrogel sheets, which can be fabricated using a facile process, have potential applications of in vitro drug assays and biological studies, including functional studies of micro- and macrostructure and tissue reconstruction. PMID:26779839
Multi-scale inference of interaction rules in animal groups using Bayesian model selection.
Richard P Mann
Full Text Available Inference of interaction rules of animals moving in groups usually relies on an analysis of large scale system behaviour. Models are tuned through repeated simulation until they match the observed behaviour. More recent work has used the fine scale motions of animals to validate and fit the rules of interaction of animals in groups. Here, we use a Bayesian methodology to compare a variety of models to the collective motion of glass prawns (Paratya australiensis. We show that these exhibit a stereotypical 'phase transition', whereby an increase in density leads to the onset of collective motion in one direction. We fit models to this data, which range from: a mean-field model where all prawns interact globally; to a spatial Markovian model where prawns are self-propelled particles influenced only by the current positions and directions of their neighbours; up to non-Markovian models where prawns have 'memory' of previous interactions, integrating their experiences over time when deciding to change behaviour. We show that the mean-field model fits the large scale behaviour of the system, but does not capture the observed locality of interactions. Traditional self-propelled particle models fail to capture the fine scale dynamics of the system. The most sophisticated model, the non-Markovian model, provides a good match to the data at both the fine scale and in terms of reproducing global dynamics, while maintaining a biologically plausible perceptual range. We conclude that prawns' movements are influenced by not just the current direction of nearby conspecifics, but also those encountered in the recent past. Given the simplicity of prawns as a study system our research suggests that self-propelled particle models of collective motion should, if they are to be realistic at multiple biological scales, include memory of previous interactions and other non-Markovian effects.
A combined hydrological and fuzzy rule based model for catchment scale nitrate dynamics
Shrestha, R. R.; Bardossy, A.; Rode, M.
2006-12-01
The diffuse nitrate pollution in rivers is driven by a complex interaction of hydrological and bio-chemical processes. Due to limited process understanding and restricted data availability, physically based approaches for the simulation of these dynamics are still associated with large uncertainties. Therefore we developed a combined deterministic - data driven approach, which consists of a spatially distributed water balance model WaSiM-ETH for the simulation of the different hydrological flow components and a fuzzy rule based model (FRBM) for the simulation of nitrate concentration in the river. Hydrological flow components are considered as dominant driving variables for the dynamic behaviour of nitrate concentrations in surface water The TOPMODEL approach is used for water balance and simulation of runoff components in the WaSiM-ETH model. The model is calibrated using an automatic parameter estimation program PEST. The simulated subsurface and surface runoff components are taken as input variables for the fuzzy rule based nitrate transport model. In addition to these runoff components, mean air temperature is included as an input variable for the consideration of seasonal variability. The FRBM consists of Mamdani type "IF- THEN" fuzzy rule system with triangular membership function in both the input and the output. 13 rule systems are used for the representation of the dynamics of the nitrate concentration in the river. The fuzzy rules are derived from a combination of expert knowledge and the input - output data using the simulated annealing optimization algorithm. The study was undertaken using 6 years of daily hydrological and nutrient time series data from the Weida catchment, which is a 100 km2 subcatchment of the Weisse Elster in the Elbe river basin, Germany. The results of the study show that the combined deterministic - fuzzy rule based model can give a good simulation of catchment scale nitrate dynamics. The WaSiM-ETH model produced a very good match
Scaling Laws and Design Principles for Multi-Cellular Wireless OFDMA Systems
Aggarwal, Rohit; Schniter, Philip
2011-01-01
In this paper, we consider the downlink of large-scale multi-cellular OFDMA-based networks and study performance bounds of the system as a function of the number of users $K$, the number of base-stations $B$, and the number of resource-blocks $N$. Here, a resource block is a collection of subcarriers such that all such collections, that are disjoint have associated independently fading channels. We derive novel upper and lower bounds on the sum-utility for a general spatial geometry of base stations, a truncated path loss model, and a variety of fading models (Rayleigh, Nakagami-$m$, Weibull, and LogNormal). We also establish the associated scaling laws and show that, in the special case of fixed number of resource blocks, a grid-based network of base stations, and Rayleigh-fading channels, the sum information capacity of the system scales as $\\Theta(B \\log\\log K/B)$ for extended networks, and as $O(B \\log\\log K)$ and $\\Omega(\\log \\log K)$ for dense networks. Interpreting these results, we develop some design...
Imaging large-scale cellular activity in spinal cord of freely behaving mice.
Sekiguchi, Kohei J; Shekhtmeyster, Pavel; Merten, Katharina; Arena, Alexander; Cook, Daniela; Hoffman, Elizabeth; Ngo, Alexander; Nimmerjahn, Axel
2016-01-01
Sensory information from mechanoreceptors and nociceptors in the skin plays key roles in adaptive and protective motor behaviours. To date, very little is known about how this information is encoded by spinal cord cell types and their activity patterns, particularly under freely behaving conditions. To enable stable measurement of neuronal and glial cell activity in behaving mice, we have developed fluorescence imaging approaches based on two- and miniaturized one-photon microscopy. We show that distinct cutaneous stimuli activate overlapping ensembles of dorsal horn neurons, and that stimulus type and intensity is encoded at the single-cell level. In contrast, astrocytes show large-scale coordinated calcium responses to intense but not weak sensory inputs. Sensory-evoked activity is potently suppressed by anaesthesia. By revealing the cellular and computational logic of spinal cord networks under behaving conditions, our approach holds promise for better understanding of healthy and aberrant spinal cord processes. PMID:27121084
Multi-Scaling Sampling: An Adaptive Sampling Method for Discovering Approximate Association Rules
Cai-Yan Jia; Xie-Ping Gao
2005-01-01
One of the obstacles of the efficient association rule mining is the explosive expansion of data sets since it is costly or impossible to scan large databases, esp., for multiple times. A popular solution to improve the speed and scalability of the association rule mining is to do the algorithm on a random sample instead of the entire database. But how to effectively define and efficiently estimate the degree of error with respect to the outcome of the algorithm, and how to determine the sample size needed are entangling researches until now. In this paper, an effective and efficient algorithm is given based on the PAC (Probably Approximate Correct) learning theory to measure and estimate sample error. Then, a new adaptive, on-line, fast sampling strategy - multi-scaling sampling - is presented inspired by MRA (Multi-Resolution Analysis) and Shannon sampling theorem, for quickly obtaining acceptably approximate association rules at appropriate sample size. Both theoretical analysis and empirical study have showed that the sampling strategy can achieve a very good speed-accuracy trade-off.
Maeda, Jin; Suzuki, Tatsuya; Takayama, Kozo
2012-01-01
A reliable large-scale design space was constructed by integrating the reliability of a scale-up rule into the Bayesian estimation without enforcing a large-scale design of experiments (DoE). A small-scale DoE was conducted using various Froude numbers (X(1)) and blending times (X(2)) in the lubricant blending process for theophylline tablets. The response surfaces, design space, and their reliability of the compression rate of the powder mixture (Y(1)), tablet hardness (Y(2)), and dissolution rate (Y(3)) on a small scale were calculated using multivariate spline interpolation, a bootstrap resampling technique, and self-organizing map clustering. A constant Froude number was applied as a scale-up rule. Experiments were conducted at four different small scales with the same Froude number and blending time in order to determine the discrepancies in the response variables between the scales so as to indicate the reliability of the scale-up rule. Three experiments under an optimal condition and two experiments under other conditions were performed on a large scale. The response surfaces on the small scale were corrected to those on the large scale by Bayesian estimation using the large-scale results and the reliability of the scale-up rule. Large-scale experiments performed under three additional sets of conditions showed that the corrected design space was more reliable than the small-scale design space even when there was some discrepancy in the pharmaceutical quality between the manufacturing scales. This approach is useful for setting up a design space in pharmaceutical development when a DoE cannot be performed at a commercial large manufacturing scale. PMID:22976324
Origin of the scaling rule for fundamental living organisms based on thermodynamics.
Fujiwara, Noboru
2003-06-01
The regular relationships between metabolic energy and body mass M of unicellular organisms, poikilotherms and homeotherms were well known as general equations. The metabolic energy rate and the life span are proportional to M(0.75) and to M(0.25), respectively. As a result, the product of the metabolic energy rate and the life time, namely, life metabolic energy, is proportional to the mass of the living organism. The origin of the scaling rules for environmental organizing systems is as follows: (1) the scaling rules for internal energy, activation energy and free energy as a function of temperature and mass of a mole of molecules. (2) The majority of species of the living organisms have the same molecules such as polysaccharides, lipids, proteins and nucleic acids in nearly same the ratio. (3) The internal energy of reactants in living organisms is equilibrium with the internal energy of water. Then, the integrated metabolic energy over the synthesizing time depends on internal energy of water and is proportional to mass M, despite the synthesizing time of the system depending on reaction rate. The proportional constant is obtained based on the thermodynamics for fundamental living organisms such as unicellular organisms and plants. Information on the environmental organizing system is also discussed. PMID:12753932
Cheng, Y.; Kekenes-Huskey, P.; Hake, J. E.; Holst, M. J.; McCammon, J. A.; Michailova, A. P.
2012-01-01
This paper presents a brief review of multi-scale modeling at the molecular to cellular scale, with new results for heart muscle cells. A finite element-based simulation package (SMOL) was used to investigate the signaling transduction at molecular and sub-cellular scales (http://mccammon.ucsd.edu/smol/, http://FETK.org) by numerical solution of the time-dependent Smoluchowski equations and a reaction-diffusion system. At the molecular scale, SMOL has yielded experimentally validated estimates of the diffusion-limited association rates for the binding of acetylcholine to mouse acetylcholinesterase using crystallographic structural data. The predicted rate constants exhibit increasingly delayed steady-state times, with increasing ionic strength, and demonstrate the role of an enzyme's electrostatic potential in influencing ligand binding. At the sub-cellular scale, an extension of SMOL solves a nonlinear, reaction-diffusion system describing Ca2+ ligand buffering and diffusion in experimentally derived rodent ventricular myocyte geometries. Results reveal the important role of mobile and stationary Ca2+ buffers, including Ca2+ indicator dye. We found that alterations in Ca2+-binding and dissociation rates of troponin C (TnC) and total TnC concentration modulate sub-cellular Ca2+ signals. The model predicts that reduced off-rate in the whole troponin complex (TnC, TnI, TnT) versus reconstructed thin filaments (Tn, Tm, actin) alters cytosolic Ca2+ dynamics under control conditions or in disease-linked TnC mutations. The ultimate goal of these studies is to develop scalable methods and theories for the integration of molecular-scale information into simulations of cellular-scale systems.
This paper presents a brief review of multi-scale modeling at the molecular to cellular scale, with new results for heart muscle cells. A finite element-based simulation package (SMOL) was used to investigate the signaling transduction at molecular and sub-cellular scales (http://mccammon.ucsd.edu/smol/, http://FETK.org) by numerical solution of the time-dependent Smoluchowski equations and a reaction-diffusion system. At the molecular scale, SMOL has yielded experimentally validated estimates of the diffusion-limited association rates for the binding of acetylcholine to mouse acetylcholinesterase using crystallographic structural data. The predicted rate constants exhibit increasingly delayed steady-state times, with increasing ionic strength, and demonstrate the role of an enzyme's electrostatic potential in influencing ligand binding. At the sub-cellular scale, an extension of SMOL solves a nonlinear, reaction-diffusion system describing Ca2+ ligand buffering and diffusion in experimentally derived rodent ventricular myocyte geometries. Results reveal the important role of mobile and stationary Ca2+ buffers, including Ca2+ indicator dye. We found that alterations in Ca2+-binding and dissociation rates of troponin C (TnC) and total TnC concentration modulate sub-cellular Ca2+ signals. The model predicts that reduced off-rate in the whole troponin complex (TnC, TnI, TnT) versus reconstructed thin filaments (Tn, Tm, actin) alters cytosolic Ca2+ dynamics under control conditions or in disease-linked TnC mutations. The ultimate goal of these studies is to develop scalable methods and theories for the integration of molecular-scale information into simulations of cellular-scale systems.
王益; Morita Kenichi
2006-01-01
Symbolic dynamics of cellular automata is introduced by coarse-graining the temporal evolution orbits. Evolution languages are defined. By using the theory of formal languages and automata, the complexity of evolution languages of the elementary cellular automaton of rule 146 is studied and it is proved that its width 1-evolution language is regular, but for every n ≥ 2 its width n-evolution language is not context-free but context-sensitive. Also, the same results hold for the equivalent (under conjugation) elementary cellular automaton of rule 182.
We present a two-dimensional continuous cellular automaton that is equivalent to a driven spring-block model. Both the conservation and the anisotropy in the model are controllable quantities. Above a critical level of conservation, the model exhibits self-organized criticality. The self-organization of this system and hence the critical exponents depend on the conservation and the boundary conditions. In the critical isotropic nonconservative phase, the exponents change continuously as a function of conservation. Furthermore, the exponents vary continuously when changing the boundary conditions smoothly. Consequently, there is no universality of the critical exponents. We discuss the relevance of this for earthquakes. Introducing anisotropy changes the scaling of the distribution function, but not the power-law exponent. We explore the phase diagram of this model. We find that at low conservation levels a localization transition occurs. We see two additional phase transitions. The first is seen when moving from the conservative into the nonconservative model. The second appears when passing from the anisotropic two-dimensional system to the purely one-dimensional system
Bennett clocking of quantum-dot cellular automata and the limits to binary logic scaling
Lent, Craig S.; Liu, Mo; Lu, Yuhui
2006-08-01
We examine power dissipation in different clocking schemes for molecular quantum-dot cellular automata (QCA) circuits. 'Landauer clocking' involves the adiabatic transition of a molecular cell from the null state to an active state carrying data. Cell layout creates devices which allow data in cells to interact and thereby perform useful computation. We perform direct solutions of the equation of motion for the system in contact with the thermal environment and see that Landauer's Principle applies: one must dissipate an energy of at least kBT per bit only when the information is erased. The ideas of Bennett can be applied to keep copies of the bit information by echoing inputs to outputs, thus embedding any logically irreversible circuit in a logically reversible circuit, at the cost of added circuit complexity. A promising alternative which we term 'Bennett clocking' requires only altering the timing of the clocking signals so that bit information is simply held in place by the clock until a computational block is complete, then erased in the reverse order of computation. This approach results in ultralow power dissipation without additional circuit complexity. These results offer a concrete example in which to consider recent claims regarding the fundamental limits of binary logic scaling.
Large-scale parallel lattice Boltzmann-cellular automaton model of two-dimensional dendritic growth
Jelinek, Bohumir; Eshraghi, Mohsen; Felicelli, Sergio; Peters, John F.
2014-03-01
An extremely scalable lattice Boltzmann (LB)-cellular automaton (CA) model for simulations of two-dimensional (2D) dendritic solidification under forced convection is presented. The model incorporates effects of phase change, solute diffusion, melt convection, and heat transport. The LB model represents the diffusion, convection, and heat transfer phenomena. The dendrite growth is driven by a difference between actual and equilibrium liquid composition at the solid-liquid interface. The CA technique is deployed to track the new interface cells. The computer program was parallelized using the Message Passing Interface (MPI) technique. Parallel scaling of the algorithm was studied and major scalability bottlenecks were identified. Efficiency loss attributable to the high memory bandwidth requirement of the algorithm was observed when using multiple cores per processor. Parallel writing of the output variables of interest was implemented in the binary Hierarchical Data Format 5 (HDF5) to improve the output performance, and to simplify visualization. Calculations were carried out in single precision arithmetic without significant loss in accuracy, resulting in 50% reduction of memory and computational time requirements. The presented solidification model shows a very good scalability up to centimeter size domains, including more than ten million of dendrites. Catalogue identifier: AEQZ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEQZ_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, UK Licensing provisions: Standard CPC license, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 29,767 No. of bytes in distributed program, including test data, etc.: 3131,367 Distribution format: tar.gz Programming language: Fortran 90. Computer: Linux PC and clusters. Operating system: Linux. Has the code been vectorized or parallelized?: Yes. Program is parallelized using MPI
Three-dimensional Anisotropy and Kohler's Rule Scaling of the Magnetoresistance in WTe2
Wang, Yong-Lei
Tungsten ditelluride (WTe2) was recently discovered to have extremely large magnetoresistance (XMR) at low temperatures and exhibits a transformative 'turn-on' temperature behavior: when the applied magnetic field H is above a certain value, the resistivity versus temperature ρ (T) curve shows a minimum at a field dependent temperature T* (H) . Since WTe2 is a layered compound with metal layers sandwiched between adjacent insulating chalcogenide layers, it is typically considered to be a two dimensional (2D) material, whereby the anisotropic magnetoresistance is attributed only to the perpendicular component of the magnetic field. Moreover, the 'turn-on' temperature behavior has been interpreted as a magnetic-field-driven metal-insulator transition or attributed to an electronic structure change. In this talk I will report on two scaling behaviors of the magnetoresistance in WTe2. The first shows that the angle dependence of the magnetoresistance follows a conventional 3D anisotropy scaling and hence reveals the electrical 3D nature of WTe2. The second demonstrates that the ρ (T , H) curves, including those with 'turn-on' temperature behavior, can be scaled with Kohler's rule. The observed Kohler's rule scaling excludes the possible existence of a magnetic-field-driven metal-insulator transition or significant contribution of an electronic structure change to the low-temperature XMR in WTe2. It indicates that both the XMR and the 'turn-on' behavior originate from the high mobilities of the charge carriers, which are strongly temperature dependent in WTe2. We also derived quantitative expressions for the magnetic field dependence of the 'turn-on' temperature T* (H) and for the temperature dependence of the resistivity ρ (T* , H) at the onset of the XMR behavior. In collaboration with L. R. Thoutam, Z. L. Xiao, J. Hu, S. Das, Z. Q. Mao, J. Wei, R. Divan, A. Luican-Mayer, G. W. Crabtree, and W. K. Kwok This work was supported by the U.S. DOE, Office of Science, BES
Rule Based Identification of Cardiac Arrhythmias from Enhanced ECG Signals Using Multi-Scale PCA
K. Sharmila
2013-09-01
Full Text Available The detection of abnormal cardiac rhythms, automatic discrimination from rhythmic heart activity, became a thrust area in clinical research. Arrhythmia detection is possible by analyzing the electrocardiogram (ECG signal features. The presence of interference signals, like power line interference (PLI, Electromyogram (EMG and baseline drift interferences, could cause serious problems during the recording of ECG signals. Many a time, they pose problem in modern control and signal processing applications by being narrow in-band interference near the frequencies carrying crucial information. This paper presents an approach for ECG signal enhancement by combining the attractive properties of principal component analysis (PCA and wavelets, resulting in multi-scale PCA. In Multi-Scale Principal Component Analysis (MSPCA, the PCA’s ability to decorrelate the variables by extracting a linear relationship and wavelet analysis are utilized. MSPCA method effectively processed the noisy ECG signal and enhanced signal features are used for clear identification of arrhythmias. In MSPCA, the principal components of the wavelet coefficients of the ECG data at each scale are computed first and are then combined at relevant scales. Statistical measures computed in terms of root mean square deviation (RMSD, root mean square error (RMSE, root mean square variation (RMSV and improvement in signal to noise ratio (SNRI revealed that the Daubechies based MSPCA outperformed the basic wavelet based processing for ECG signal enhancement. With enhanced signal features obtained after MSPCA processing, the detectable measures, QRS duration and R-R interval are evaluated. By using the rule base technique, projecting the detectable measures on a two dimensional area, various arrhythmias are detected depending upon the beat falling into particular place of the two dimensional area.
Secure D2D Communication in Large-Scale Cognitive Cellular Networks: A Wireless Power Transfer Model
Liu, Yuanwei; Wang, Lifeng; Zaidi, Syed Ali Raza; Elkashlan, Maged; Duong, Trung Q.
2015-01-01
In this paper, we investigate secure device-to-device (D2D) communication in energy harvesting large-scale cognitive cellular networks. The energy constrained D2D transmitter harvests energy from multiantenna equipped power beacons (PBs), and communicates with the corresponding receiver using the spectrum of the primary base stations (BSs). We introduce a power transfer model and an information signal model to enable wireless energy harvesting and secure information transmission. In the power...
Multi-Scale Modeling of Respiration: Linking External to Cellular Respiration during Exercise
Zhou, Haiying; Lai, Nicola; Saidel, Gerald M.; Cabrera, Marco E.
2009-01-01
In human studies investigating factors that control cellular respiration in working skeletal muscle, pulmonary VO2 dynamics (VO2p) measured at the mouth by indirect calorimetry is typically used to represent muscle O2 consumption (UO2m). Furthermore, measurement of muscle oxygenation using near-infrared spectroscopy has provided information on the dynamic balance between oxygen delivery and oxygen consumption at the microvascular level. To relate these measurements and gain quantitative under...
In Silico Modeling of the Immune System: Cellular and Molecular Scale Approaches
Mariagrazia Belfiore
2014-01-01
Full Text Available The revolutions in biotechnology and information technology have produced clinical data, which complement biological data. These data enable detailed descriptions of various healthy and diseased states and responses to therapies. For the investigation of the physiology and pathology of the immune responses, computer and mathematical models have been used in the last decades, enabling the representation of biological processes. In this modeling effort, a major issue is represented by the communication between models that work at cellular and molecular level, that is, multiscale representation. Here we sketch some attempts to model immune system dynamics at both levels.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Other information as of 2010. It is described as 'Cell...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Published Reports/Deeds information as of 2006. It is...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:63360 (1in=1mile) scale, was produced all or in part from Not Provided information as of 2008. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Orthoimagery information as of 2010. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Published Reports/Deeds information as of 2008. It is...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Hardcopy Maps information as of 2010. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Hardcopy Maps information as of 2007. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:63360 (1in=1mile) scale, was produced all or in part from Not Provided information as of 2008. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Orthoimagery information as of 2007. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Other information as of 2008. It is described as 'Cell...
Identification of large-scale cellular structures on the Sun based on the SDO and PSPT data
Efremov, V I; Solovev, A A
2014-01-01
Three independent sets of data: i). series of filtergrams obtained in line CaII K (393.416 nm) with the ground-based telescope Precision Solar Photometric Telescope (PSPT) of Mauna Loa Solar Observatory; ii). series of filtergrams of Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO) in {\\lambda}160 nm and iii). series of magnetograms of Helioseismic and Magnetic Imager (HMI) of SDO have been processed to reveal reliably the existence of spatial cellular structures on the solar photosphere at scale about of 300 arcsec. This scale is intermediate between supergranules and giant cells (~30,000 and ~300,000 kilometers across, respectively). To identify the different spatial structures the tens of two-dimensional power spectra (2DFFT) have been averaged. For one-dimensional photometric cross sections of frames, the Fourier power spectra (FFT) and wavelet transforms (Morlet 5-th order) have been calculated.
EFFICIENT NANO-SCALE ADMIXTURE FOR FOAM STABILITY IMPROVEMENT OF CELLULAR CONCRETES
Grishina Аnna Nikolaevna
2012-10-01
Full Text Available The authors present their methodology of synthesis of a nano-scale additive designated for the stabilization of synthetic foaming agents. The nano-scale admixture is composed of iron hydroxide (III sol and aqueous sodium hydro silicates (water glass. Besides the above method, the topological structural model of the nano-scale additive is proposed. The additive stability was assessed upon its one-day storage (with the foaming agent added, and the assessment data are provided in the article. The authors have discovered that it is advisable to use an iron chloride solution in the concentration of 1 % to manufacture the iron hydroxide (III sol. The authors have also discovered that the rate of jellification goes up in the process of injecting the foaming agent into the foam that contains the nano-scale admixture developed by the authors. Dependence between the amount of sodium hydro silicate and the viscosity of the system composed of the water glass and the sol of iron hydroxide (III is examined in detail. The authors have identified that the average water glass viscosity curve demonstrates an extreme nature. The additive is used for the stabilization of the foam generated by synthetic foaming agents. The injection of the proposed additive improves foam stability. It is noteworthy that this positive result is free from any negative side effects.
The purpose of this study was to develop a new method for automated lung nodule detection in serial section CT images with using the characteristics of the 3D appearance of the nodules that distinguish themselves from the vessels. Lung nodules were detected in four steps. First, to reduce the number of region of interests (ROIs) and the computation time, the lung regions of the CTs were segmented using Genetic Cellular Neural Networks (G-CNN). Then, for each lung region, ROIs were specified with using the 8 directional search; +1 or -1 values were assigned to each voxel. The 3D ROI image was obtained by combining all the 2-Dimensional (2D) ROI images. A 3D template was created to find the nodule-like structures on the 3D ROI image. Convolution of the 3D ROI image with the proposed template strengthens the shapes that are similar to those of the template and it weakens the other ones. Finally, fuzzy rule based thresholding was applied and the ROI's were found. To test the system's efficiency, we used 16 cases with a total of 425 slices, which were taken from the Lung Image Database Consortium (LIDC) dataset. The computer aided diagnosis (CAD) system achieved 100% sensitivity with 13.375 FPs per case when the nodule thickness was greater than or equal to 5.625 mm. Our results indicate that the detection performance of our algorithm is satisfactory, and this may well improve the performance of computer aided detection of lung nodules
Cellular defibrillation: interaction of micro-scale electric fields with voltage-gated ion channels.
Kargol, Armin; Malkinski, Leszek; Eskandari, Rahmatollah; Carter, Maya; Livingston, Daniel
2015-09-01
We study the effect of micro-scale electric fields on voltage-gated ion channels in mammalian cell membranes. Such micro- and nano-scale electric fields mimic the effects of multiferroic nanoparticles that were recently proposed [1] as a novel way of controlling the function of voltage-sensing biomolecules such as ion channels. This article describes experimental procedures and initial results that reveal the effect of the electric field, in close proximity of cells, on the ion transport through voltage-gated ion channels. We present two configurations of the whole-cell patch-clamping apparatus that were used to detect the effect of external stimulation on ionic currents and discuss preliminary results that indicate modulation of the ionic currents consistent with the applied stimulus. PMID:26067055
Large-Scale Fading Behavior for a Cellular Network with Uniform Spatial Distribution
Abdulla, Mouhamed; Shayan, Yousef R.
2013-01-01
Large-scale fading (LSF) between interacting nodes is a fundamental element in radio communications, responsible for weakening the propagation, and thus worsening the service quality. Given the importance of channel-losses in general, and the inevitability of random spatial geometry in real-life wireless networks, it was then natural to merge these two paradigms together in order to obtain an improved stochastical model for the LSF indicator. Therefore, in exact closed-form notation, we gener...
Scaling of Geographic Space as a Universal Rule for Map Generalization
Jiang, Bin; Liu, Xintao; Jia, Tao
2011-01-01
Map generalization is a process of producing maps at different levels of detail by retaining essential properties of the underlying geographic space. In this paper, we explore how the map generalization process can be guided by the underlying scaling of geographic space. The scaling of geographic space refers to the fact that in a geographic space small things are far more common than large ones. In the corresponding rank-size distribution, this scaling property is characterized by a heavy ta...
de la Cruz, Roberto; Spill, Fabian; Alarcón, Tomás
2016-01-01
We propose a modelling framework to analyse the stochastic behaviour of heterogeneous, multi-scale cellular populations. We illustrate our methodology with a particular example in which we study a population with an oxygen-regulated proliferation rate. Our formulation is based on an age-dependent stochastic process. Cells within the population are characterised by their age. The age-dependent (oxygen-regulated) birth rate is given by a stochastic model of oxygen-dependent cell cycle progression. We then formulate an age-dependent birth-and-death process, which dictates the time evolution of the cell population. The population is under a feedback loop which controls its steady state size: cells consume oxygen which in turns fuels cell proliferation. We show that our stochastic model of cell cycle progression allows for heterogeneity within the cell population induced by stochastic effects. Such heterogeneous behaviour is reflected in variations in the proliferation rate. Within this set-up, we have established...
J Murdock; W Dodds; J Reffner; D Wetzel
2011-12-31
The microscope and infrared spectrometer are two of the most useful tools for the study of biological materials, and their combined analytical power far exceeds the sum of the two. Performing molecular spectroscopy through a microscope superimposes chemical information onto the physical microstructure obtained from the optical microscope when visible and infrared information are collected under the same conditions. The instrument developments that enable current infrared microspectroscopic studies began with the introduction of the first research-grade infrared microscope, patented in 1989 (1). By 1993, published reports using this method to determine macroalgae (seaweed) cell-wall composition appeared (2-4). Since these initial reports, the use of infrared microspectroscopy (IMS) in microalgal (single cells or groups of cells) research has grown. Primarily, cultured algae have been used to hone IMS methodology and evaluate its capabilities in algal research (5-8). Studies involving natural, mixed species assemblages, which can utilize the spatial resolution potential of this technique fully are rare (9-11). For instance, in a recent review of IMS microalgal ecological research (12), only 3 of the 29 peer-reviewed publications investigated natural algal assemblages. Both thermal and synchrotron infrared sources provide a resolution capable of measuring individual algae in mixed species assemblages, and each has its advantages. For example, thermal source IMS is more accessible, allowing more samples to be analyzed than synchrotron IMS. However, synchrotron IMS with confocal masking provides superior resolution, which can be critical in isolating small or contiguous cells. Algal ecology is the study of the interaction between algae and their environment. Infrared microspectroscopy addresses a major logistical problem in this field, obtaining species-specific cellular biochemical information from natural, mixed-species assemblages (11,12). Benthic (bottom
Yongkun Li; Lei Wang; Yu Fei
2014-01-01
A class of shunting inhibitory cellular neural networks of neutral type with time-varying delays in the leakage term on time scales is proposed. Based on the exponential dichotomy of linear dynamic equations on time scales, fixed point theorems, and calculus on time scales we obtain some sufficient conditions for the existence and global exponential stability of periodic solutions for that class of neural networks. The results of this paper are completely new and complementary to the previous...
Runchun Mark Wang
2015-05-01
Full Text Available We present a neuromorphic implementation of multiple synaptic plasticity learning rules, which include both Spike Timing Dependent Plasticity (STDP and Spike Timing Dependent Delay Plasticity (STDDP. We present a fully digital implementation as well as a mixed-signal implementation, both of which use a novel dynamic-assignment time-multiplexing approach and support up to 2^26 (64M synaptic plasticity elements. Rather than implementing dedicated synapses for particular types of synaptic plasticity, we implemented a more generic synaptic plasticity adaptor array that is separate from the neurons in the neural network. Each adaptor performs synaptic plasticity according to the arrival times of the pre- and post-synaptic spikes assigned to it, and sends out a weighted and/or delayed pre-synaptic spike to the target synapse in the neural network. This strategy provides great flexibility for building complex large-scale neural networks, as a neural network can be configured for multiple synaptic plasticity rules without changing its structure. We validate the proposed neuromorphic implementations with measurement results and illustrate that the circuits are capable of performing both STDP and STDDP. We argue that it is practical to scale the work presented here up to 2^36 (64G synaptic adaptors on a current high-end FPGA platform.
A common scaling rule for abundance, energetics, and production of parasitic and free-living species
Hechinger, Ryan F.; Lafferty, Kevin D.; Dobson, Andy P.; Brown, James H.; Kuris, Armand M.
2011-01-01
The metabolic theory of ecology uses the scaling of metabolism with body size and temperature to explain the causes and consequences of species abundance. However, the theory and its empirical tests have never simultaneously examined parasites alongside free-living species. This is unfortunate because parasites represent at least half of species diversity. We show that metabolic scaling theory could not account for the abundance of parasitic or free-living species in three estuarine food webs until accounting for trophic dynamics. Analyses then revealed that the abundance of all species uniformly scaled with body mass to the - 3/4 power. This result indicates "production equivalence," where biomass production within trophic levels is invariant of body size across all species and functional groups: invertebrate or vertebrate, ectothermic or endothermic, and free-living or parasitic.
Jet energy scale setting with 'γ+Jet' events at LHC energies. Generalities, selection rules
'γ+Jet' events, based on the qq bar → g+γ and qg → q+γ subprocesses, are proposed for jet energy scale setting and hadron calorimeter calibration at LHC energies. General features and selection criteria of 'γ+Jet' events that would provide a good Ptγ-PtJet balance are described. CMS detector geometry is taken as the basement
Updated Neuronal Scaling Rules for the Brains of Glires (Rodents/Lagomorphs)
Herculano-Houzel, Suzana; Ribeiro, Pedro; Campos, Leandro; Valotta da Silva, Alexandre; Torres, Laila B.; Catania, Kenneth C.; Kaas, Jon H.
2011-01-01
Brain size scales as different functions of its number of neurons across mammalian orders such as rodents, primates, and insectivores. In rodents, we have previously shown that, across a sample of 6 species, from mouse to capybara, the cerebral cortex, cerebellum and the remaining brain structures increase in size faster than they gain neurons, with an accompanying decrease in neuronal density in these structures [Herculano-Houzel et al.: Proc Natl Acad Sci USA 2006;103:12138–12143]. Importan...
Construction of spatial scale-free networks on a lattice by using a democratic rule
The Rozenfeld, Cohen, ben-Avraham and Havlin scale-free network on regular Euclidean lattices has been observed to have two degree distribution exponents. We propose a modification of this network by assigning links between lattice sites in a democratic manner: at a certain intermediate step all sites get the same opportunity to acquire links within a certain range. This network has only a few unsaturated nodes and has only one degree distribution exponent, exactly equal to that of the assigned distribution. Non-trivial assortative correlations are found to be present in this network. Also the strength–degree relation is found to be non-linear
Yongkun Li
2014-01-01
Full Text Available A class of shunting inhibitory cellular neural networks of neutral type with time-varying delays in the leakage term on time scales is proposed. Based on the exponential dichotomy of linear dynamic equations on time scales, fixed point theorems, and calculus on time scales we obtain some sufficient conditions for the existence and global exponential stability of periodic solutions for that class of neural networks. The results of this paper are completely new and complementary to the previously known results even if the time scale =ℝ or ℤ. Moreover, we present illustrative numerical examples to show the feasibility of our results.
Cellular automaton for chimera states
García-Morales, Vladimir
2016-01-01
A minimalistic model for chimera states is presented. The model is a cellular automaton (CA) which depends on only one adjustable parameter, the range of the nonlocal coupling, and is built from elementary cellular automata and the majority (voting) rule. This suggests the universality of chimera-like behavior from a new point of view: Already simple CA rules based on the majority rule exhibit this behavior. After a short transient, we find chimera states for arbitrary initial conditions, the...
Beamish, Eric Edward
This project was designed to plan a short study self-instructional film for teaching the use of the C and D scales of the slide rule in solving simple problems in multiplication and to produce one of these films. The film was designed to exploit the unique presentational features of a cartridge loading projector equipped with automatic stop and…
Scolozzi, Rocco; Geneletti, Davide
2011-03-01
In human dominated landscapes, ecosystems are under increasing pressures caused by urbanization and infrastructure development. In Alpine valleys remnant natural areas are increasingly affected by habitat fragmentation and loss. In these contexts, there is a growing risk of local extinction for wildlife populations; hence assessing the consequences on biodiversity of proposed land use changes is extremely important. The article presents a methodology to assess the impacts of land use changes on target species at a local scale. The approach relies on the application of ecological profiles of target species for habitat potential (HP) assessment, using high resolution GIS-data within a multiple level framework. The HP, in this framework, is based on a species-specific assessment of the suitability of a site, as well of surrounding areas. This assessment is performed through spatial rules, structured as sets of queries on landscape objects. We show that by considering spatial dependencies in habitat assessment it is possible to perform better quantification of impacts of local-level land use changes on habitats.
Bhattacharyya-Pakrasi Maitrayee
2010-08-01
Full Text Available Abstract Background Cyanobacteria are the only known prokaryotes capable of oxygenic photosynthesis. They play significant roles in global biogeochemical cycles and carbon sequestration, and have recently been recognized as potential vehicles for production of renewable biofuels. Synechocystis sp. PCC 6803 has been extensively used as a model organism for cyanobacterial studies. DNA microarray studies in Synechocystis have shown varying degrees of transcriptome reprogramming under altered environmental conditions. However, it is not clear from published work how transcriptome reprogramming affects pre-existing networks of fine-tuned cellular processes. Results We have integrated 163 transcriptome data sets generated in response to numerous environmental and genetic perturbations in Synechocystis. Our analyses show that a large number of genes, defined as the core transcriptional response (CTR, are commonly regulated under most perturbations. The CTR contains nearly 12% of Synechocystis genes found on its chromosome. The majority of genes in the CTR are involved in photosynthesis, translation, energy metabolism and stress protection. Our results indicate that a large number of differentially regulated genes identified in most reported studies in Synechocystis under different perturbations are associated with the general stress response. We also find that a majority of genes in the CTR are coregulated with 25 regulatory genes. Some of these regulatory genes have been implicated in cellular responses to oxidative stress, suggesting that reactive oxygen species are involved in the regulation of the CTR. A Bayesian network, based on the regulation of various KEGG pathways determined from the expression patterns of their associated genes, has revealed new insights into the coordination between different cellular processes. Conclusion We provide here the first integrative analysis of transcriptome data sets generated in a cyanobacterium. This
Abdullah Al Mamun; Brook, Ryan K.
2015-01-01
One of the key issues facing fishery managers, policy-makers and researchers has been acknowledging local institutions and rule systems for managing common pool resources. In this paper, we discuss local institutions and rule systems of community fisheries from two oxbow lake Fisheries in Southern Bangladesh. Both of the fisheries have been under private and state management systems resulting in different management outcomes. Control of fishers and stocking for production enhancement have bee...
The BIOCLIM project on modelling sequential Biosphere systems under Climate change for radioactive waste disposal is part of the EURATOM fifth European framework programme. The project was launched in October 2000 for a three-year period. The project aims at providing a scientific basis and practical methodology for assessing the possible long term impacts on the safety of radioactive waste repositories in deep formations due to climate and environmental change. Five work packages (WP) have been identified to fulfill the project objectives. One of the tasks of BIOCLIM WP3 was to develop a rule-based approach for down-scaling from the MoBidiC model of intermediate complexity in order to provide consistent estimates of monthly temperature and precipitation for the specific regions of interest to BIOCLIM (Central Spain, Central England and Northeast France, together with Germany and the Czech Republic). A statistical down-scaling methodology has been developed by Philippe Marbaix of CEA/LSCE for use with the second climate model of intermediate complexity used in BIOCLIM - CLIMBER-GREMLINS. The rule-based methodology assigns climate states or classes to a point on the time continuum of a region according to a combination of simple threshold values which can be determined from the coarse scale climate model. Once climate states or classes have been defined, monthly temperature and precipitation climatologies are constructed using analogue stations identified from a data base of present-day climate observations. The most appropriate climate classification for BIOCLIM purposes is the Koeppen/Trewartha scheme. This scheme has the advantage of being empirical, but only requires monthly averages of temperature and precipitation as input variables. Section 2 of this deliverable (D8a) outline how each of the eight methodological steps have been undertaken for each of the three main BIOCLIM study regions (Central England, Northeast France and Central Spain) using Mo
Taghipoor, Masoomeh; van Milgen, Jaap; Gondret, Florence
2016-09-01
Variations in energy storage and expenditure are key elements for animals adaptation to rapidly changing environments. Because of the multiplicity of metabolic pathways, metabolic crossroads and interactions between anabolic and catabolic processes within and between different cells, the flexibility of energy stores in animal cells is difficult to describe by simple verbal, textual or graphic terms. We propose a mathematical model to study the influence of internal and external challenges on the dynamic behavior of energy stores and its consequence on cell energy status. The role of the flexibility of energy stores on the energy equilibrium at the cellular level is illustrated through three case studies: variation in eating frequency (i.e., glucose input), level of physical activity (i.e., ATP requirement), and changes in cell characteristics (i.e., maximum capacity of glycogen storage). Sensitivity analysis has been performed to highlight the most relevant parameters of the model; model simulations have then been performed to illustrate how variation in these key parameters affects cellular energy balance. According to this analysis, glycogen maximum accumulation capacity and homeostatic energy demand are among the most important parameters regulating muscle cell metabolism to ensure its energy equilibrium. PMID:27338303
Taborda, A; Benabdallah, N; Desbrée, A
2016-02-01
The Auger-electrons emitted by (99m)Tc have been recently associated with the induction of thyroid stunning in in vivo experiments in mice, making the dosimetry at the sub-cellular level of (99m)Tc a pertinent and pressing subject. The S-values for (99m)Tc were calculated using MCNP6, which was first validated for studies at the sub-cellular scale and for low energies electrons. The calculation was then performed for (99m)Tc within different cellular compartments in a single mouse thyroid follicle model, considering the radiative and non-radiative transitions of the (99m)Tc radiation spectrum. It was shown that the contribution of the (99m)Tc Auger and low energy electrons to the absorbed dose to the follicular cells' nucleus is important, being at least of the same order of magnitude compared to the emitted photons' contribution and cannot be neglected. The results suggest that Auger-electrons emitted by (99m)Tc play a significant role in the occurrence of the thyroid stunning effect in mice. PMID:26704702
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Hardcopy Maps information as of 2010. It is described as...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Other information as of 2006. It is described as 'Cell...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Field Survey/GPS information as of 2010. It is described...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Published Reports/Deeds information as of 2010. It is...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Field Survey/GPS information as of 2003. It is described...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:24000 (1in=2000ft) scale as of 2007. It is described as 'Serve as base information for use in GIS systems for...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Orthoimagery information as of 2010. It is described as...
We have designed new nano-probes applicable for both positron emission tomography (PET) and optical fluorescence in vivo imaging. Fluorine-18, which is commonly used for clinical imaging, has been coupled to phospholipid quantum dot (QD) micelles. This probe was injected in mice and we demonstrated that its dynamic quantitative whole body biodistribution and pharmacokinetics could be monitored using PET as well as the kinetics of their cellular uptake using in vivo fibered confocal fluorescence imaging. Phospholipid micelle encapsulation of QDs provides a highly versatile surface chemistry to conjugate multiple chemicals and biomolecules with controlled QD: molecule valency. Here, we show that, in contrast with several previous studies using other QD polymer coatings, these phospholipid QD micelles exhibit long circulation half-time in the blood stream (on the order of 2 h) and slow uptake by reticulo-endothelial system. (authors)
Mustata, Gina-Mirela
It has been proposed that diffusion in the plasma membrane of eukaryotic cells it is compartmentalized due to the interaction with the underlying actin-based membrane skeleton that comes into close proximity to the lipid bilayer. The cytoskeleton is a dynamic structure that maintains cell shape, enables cell motion, and plays important roles in both intra-cellular transport and cellular division. We show here the evidence of plasma membrane compartmentalization using Single Particle Tracking (SPT) and Atomic Force Microscopy (AFM) imaging. SPT of Quantum dot labeled lipid in the plasma membrane of live normal rat kidney cells show compartments ranging from 325 nm to 391 nm depending on the sampling time. Using AFM imaging of live NRK cell in the presence of phalloidin, the membrane compartmentalization it is visible with the average size of the compartments of 325 +/- 10 nm (the main peak is centered at 260 nm). Further, the underlying membrane skeleton in fixed cells was directly imaged after partial removal of the plasma membrane to reveal size of the membrane skeleton meshwork of 339 +/- 10 nm. A new method of measuring the characteristics of the actin meshwork was proposed. Probing the local compliance of the plasma membrane through the deflection of a soft AFM cantilever we can expect that the stiffness of the membrane will be higher at locations directly above a cortical actin. This new method provided information about the structure of the skeletal meshwork of neuronal cell body predicting an average compartment size of about 132 nm. This was confirmed through SPT of QD-lipid incorporated into the neuronal cell membrane.
Selle, B.; Githui, F.; Thayalakumaran, T.
2009-04-01
The rootzone of a field or farm in irrigated landscapes is the logical unit that can be managed or influenced by farmers, catchment managers and water authorities. Increasing scarcity, variability and expensive nature of water supplies necessitates better understanding of the rootzone water balance in irrigated landscapes. The major terms of the annual water balance in the rootzone include rainfall, irrigation, evapotranspiration, deep percolation below the rootzone and runoff. While information on annual rainfall, irrigation and evapotranspiration can often be readily obtained at field to farm scales, deep percolation and runoff are typically unavailable as their continuous measurement is difficult and/or uneconomical. Consequently, these terms are often calculated using models that are able to simulate the rootzone water balance. In this case study, we developed a rule-of-thumb approach to estimate annual deep percolation and runoff for the Barr Creek catchment in northern Victoria, Australia. Firstly, annual deep percolation and runoff were calculated at field to farm scales using an integrated SWAT-MODFLOW model calibrated against a comprehensive data set including drain flows and salinity, remotely sensed evapotranspiration and watertable levels. Secondly, a rule-of-thumb approach was developed to approximate annual deep percolation and runoff from readily available information on annual irrigation, rainfall, evapotranspiration, soils, watertable levels and landuse. This rule-of-thumb approach can be applied to continuously estimate deep percolation and runoff.
Gabriela Moura
Full Text Available BACKGROUND: Codon usage and codon-pair context are important gene primary structure features that influence mRNA decoding fidelity. In order to identify general rules that shape codon-pair context and minimize mRNA decoding error, we have carried out a large scale comparative codon-pair context analysis of 119 fully sequenced genomes. METHODOLOGIES/PRINCIPAL FINDINGS: We have developed mathematical and software tools for large scale comparative codon-pair context analysis. These methodologies unveiled general and species specific codon-pair context rules that govern evolution of mRNAs in the 3 domains of life. We show that evolution of bacterial and archeal mRNA primary structure is mainly dependent on constraints imposed by the translational machinery, while in eukaryotes DNA methylation and tri-nucleotide repeats impose strong biases on codon-pair context. CONCLUSIONS: The data highlight fundamental differences between prokaryotic and eukaryotic mRNA decoding rules, which are partially independent of codon usage.
Chapman, E.; Yang, J.; Crawshaw, J.; Boek, E. S.
2012-04-01
In the 1980s, Lenormand et al. carried out their pioneering work on displacement mechanisms of fluids in etched networks [1]. Here we further examine displacement mechanisms in relation to capillary filling rules for spontaneous imbibition. Understanding the role of spontaneous imbibition in fluid displacement is essential for refining pore network models. Generally, pore network models use simple capillary filling rules and here we examine the validity of these rules for spontaneous imbibition. Improvement of pore network models is vital for the process of 'up-scaling' to the field scale for both enhanced oil recovery (EOR) and carbon sequestration. In this work, we present our experimental microfluidic research into the displacement of both supercritical CO2/deionised water (DI) systems and analogous n-decane/air - where supercritical CO2 and n-decane are the respective wetting fluids - controlled by imbibition at the pore scale. We conducted our experiments in etched PMMA and silicon/glass micro-fluidic hydrophobic chips. We first investigate displacement in single etched pore junctions, followed by displacement in complex network designs representing actual rock thin sections, i.e. Berea sandstone and Sucrosic dolomite. The n-decane/air experiments were conducted under ambient conditions, whereas the supercritical CO2/DI water experiments were conducted under high temperature and pressure in order to replicate reservoir conditions. Fluid displacement in all experiments was captured via a high speed video microscope. The direction and type of displacement the imbibing fluid takes when it enters a junction is dependent on the number of possible channels in which the wetting fluid can imbibe, i.e. I1, I2 and I3 [1]. Depending on the experiment conducted, the micro-models were initially filled with either DI water or air before the wetting fluid was injected. We found that the imbibition of the wetting fluid through a single pore is primarily controlled by the
Xuan Le
2013-01-01
Full Text Available Surface topographical features on biomaterials, both at the submicrometre and nanometre scales, are known to influence the physicochemical interactions between biological processes involving proteins and cells. The nanometre-structured surface features tend to resemble the extracellular matrix, the natural environment in which cells live, communicate, and work together. It is believed that by engineering a well-defined nanometre scale surface topography, it should be possible to induce appropriate surface signals that can be used to manipulate cell function in a similar manner to the extracellular matrix. Therefore, there is a need to investigate, understand, and ultimately have the ability to produce tailor-made nanometre scale surface topographies with suitable surface chemistry to promote favourable biological interactions similar to those of the extracellular matrix. Recent advances in nanoscience and nanotechnology have produced many new nanomaterials and numerous manufacturing techniques that have the potential to significantly improve several fields such as biological sensing, cell culture technology, surgical implants, and medical devices. For these fields to progress, there is a definite need to develop a detailed understanding of the interaction between biological systems and fabricated surface structures at both the micrometre and nanometre scales.
Cellular automaton for chimera states
García-Morales, Vladimir
2016-04-01
A minimalistic model for chimera states is presented. The model is a cellular automaton (CA) which depends on only one adjustable parameter, the range of the nonlocal coupling, and is built from elementary cellular automata and the majority (voting) rule. This suggests the universality of chimera-like behavior from a new point of view: Already simple CA rules based on the majority rule exhibit this behavior. After a short transient, we find chimera states for arbitrary initial conditions, the system spontaneously splitting into stable domains separated by static boundaries, some synchronously oscillating and the others incoherent. When the coupling range is local, nontrivial coherent structures with different periodicities are formed.
Finney, L.; Mandava, S.; Ursos, L.; Zhang, W.; Rodi, D.; Vogt, S.; Legnini, D.; Maser, J.; Ikpatt, F.; Olopade, O. I.; Glesne, D.; Univ. of Chicago
2007-02-13
Although copper has been reported to influence numerous proteins known to be important for angiogenesis, the enhanced sensitivity of this developmental process to copper bioavailability has remained an enigma, because copper metalloproteins are prevalent and essential throughout all cells. Recent developments in x-ray optics at third-generation synchrotron sources have provided a resource for highly sensitive visualization and quantitation of metalloproteins in biological samples. Here, we report the application of x-ray fluorescence microscopy (XFM) to in vitro models of angiogenesis and neurogenesis, revealing a surprisingly dramatic spatial relocalization specific to capillary formation of 80-90% of endogenous cellular copper stores from intracellular compartments to the tips of nascent endothelial cell filopodia and across the cell membrane. Although copper chelation had no effect on process formation, an almost complete ablation of network formation was observed. XFM of highly vascularized ductal carcinomas showed copper clustering in putative neoangiogenic areas. This use of XFM for the study of a dynamic developmental process not only sheds light on the copper requirement for endothelial tube formation but highlights the value of synchrotron-based facilities in biological research.
Although copper has been reported to influence numerous proteins known to be important for angiogenesis, the enhanced sensitivity of this developmental process to copper bioavailability has remained an enigma, because copper metalloproteins are prevalent and essential throughout all cells. Recent developments in x-ray optics at third-generation synchrotron sources have provided a resource for highly sensitive visualization and quantitation of metalloproteins in biological samples. Here, we report the application of x-ray fluorescence microscopy (XFM) to in vitro models of angiogenesis and neurogenesis, revealing a surprisingly dramatic spatial relocalization specific to capillary formation of 80-90% of endogenous cellular copper stores from intracellular compartments to the tips of nascent endothelial cell filopodia and across the cell membrane. Although copper chelation had no effect on process formation, an almost complete ablation of network formation was observed. XFM of highly vascularized ductal carcinomas showed copper clustering in putative neoangiogenic areas. This use of XFM for the study of a dynamic developmental process not only sheds light on the copper requirement for endothelial tube formation but highlights the value of synchrotron-based facilities in biological research
Nowotny, Thomas; Requardt, Manfred
1998-01-01
Starting from the working hypothesis that both physics and the corresponding mathematics have to be described by means of discrete concepts on the Planck-scale, one of the many problems one has to face is to find the discrete protoforms of the building blocks of continuum physics and mathematics. In the following we embark on developing such concepts for irregular structures like (large) graphs or networks which are intended to emulate (some of) the generic properties of the presumed combinat...
Mohanty, Sankhya; Hattel, Jesper H.
2016-04-01
Residual stresses and deformations continue to remain one of the primary challenges towards expanding the scope of selective laser melting as an industrial scale manufacturing process. While process monitoring and feedback-based process control of the process has shown significant potential, there is still dearth of techniques to tackle the issue. Numerical modelling of selective laser melting process has thus been an active area of research in the last few years. However, large computational resource requirements have slowed the usage of these models for optimizing the process. In this paper, a calibrated, fast, multiscale thermal model coupled with a 3D finite element mechanical model is used to simulate residual stress formation and deformations during selective laser melting. The resulting reduction in thermal model computation time allows evolutionary algorithm-based optimization of the process. A multilevel optimization strategy is adopted using a customized genetic algorithm developed for optimizing cellular scanning strategy for selective laser melting, with an objective of reducing residual stresses and deformations. The resulting thermo-mechanically optimized cellular scanning strategies are compared with standard scanning strategies and have been used to manufacture standard samples.
Quantum features of natural cellular automata
Elze, Hans-Thomas
2016-03-01
Cellular automata can show well known features of quantum mechanics, such as a linear rule according to which they evolve and which resembles a discretized version of the Schrödinger equation. This includes corresponding conservation laws. The class of “natural” Hamiltonian cellular automata is based exclusively on integer-valued variables and couplings and their dynamics derives from an Action Principle. They can be mapped reversibly to continuum models by applying Sampling Theory. Thus, “deformed” quantum mechanical models with a finite discreteness scale l are obtained, which for l → 0 reproduce familiar continuum results. We have recently demonstrated that such automata can form “multipartite” systems consistently with the tensor product structures of nonrelativistic many-body quantum mechanics, while interacting and maintaining the linear evolution. Consequently, the Superposition Principle fully applies for such primitive discrete deterministic automata and their composites and can produce the essential quantum effects of interference and entanglement.
SELF-ORGANIZED CRITICALITY AND CELLULAR AUTOMATA
CREUTZ,M.
2007-01-01
Cellular automata provide a fascinating class of dynamical systems based on very simple rules of evolution yet capable of displaying highly complex behavior. These include simplified models for many phenomena seen in nature. Among other things, they provide insight into self-organized criticality, wherein dissipative systems naturally drive themselves to a critical state with important phenomena occurring over a wide range of length and the scales. This article begins with an overview of self-organized criticality. This is followed by a discussion of a few examples of simple cellular automaton systems, some of which may exhibit critical behavior. Finally, some of the fascinating exact mathematical properties of the Bak-Tang-Wiesenfeld sand-pile model [1] are discussed.
Quantum features of natural cellular automata
Elze, Hans-Thomas
2016-01-01
Cellular automata can show well known features of quantum mechanics, such as a linear rule according to which they evolve and which resembles a discretized version of the Schroedinger equation. This includes corresponding conservation laws. The class of "natural" Hamiltonian cellular automata is based exclusively on integer-valued variables and couplings and their dynamics derives from an Action Principle. They can be mapped reversibly to continuum models by applying Sampling Theory. Thus, "deformed" quantum mechanical models with a finite discreteness scale $l$ are obtained, which for $l\\rightarrow 0$ reproduce familiar continuum results. We have recently demonstrated that such automata can form "multipartite" systems consistently with the tensor product structures of nonrelativistic many-body quantum mechanics, while interacting and maintaining the linear evolution. Consequently, the Superposition Principle fully applies for such primitive discrete deterministic automata and their composites and can produce...
Day, M. S.; Bell, J. B.; Cheng, R. K.; Tachibana, S.; Beckner, V. E.; Lijewski, M. J.
2009-07-01
One strategy for reducing US dependence on petroleum is to develop new combustion technologies for burning the fuel-lean mixtures of hydrogen or hydrogen-rich syngas fuels obtained from the gasification of coal and biomass. Fuel-flexible combustion systems based on lean premixed combustion have the potential for dramatically reducing pollutant emissions in transportation systems, heat and stationary power generation. However, lean premixed flames are highly susceptible to fluid-dynamical combustion instabilities making robust and reliable systems difficult to design. Low swirl burners are emerging as an important technology for meeting design requirements in terms of both reliability and emissions for next generation combustion devices. In this paper, we present simulations of a lean, premixed hydrogen flame stabilized on a laboratory-scale low swirl burner. The simulations use detailed chemistry and transport without incorporating explicit models for turbulence or turbulence/chemistry interaction. Here we discuss the overall structure of the flame and compare with experimental data. We also use the simulation data to elucidate the characteristics of the turbulent flame interaction and how this impacts the analysis of experimental measurements.
One strategy for reducing US dependence on petroleum is to develop new combustion technologies for burning the fuel-lean mixtures of hydrogen or hydrogen-rich syngas fuels obtained from the gasification of coal and biomass. Fuel-flexible combustion systems based on lean premixed combustion have the potential for dramatically reducing pollutant emissions in transportation systems, heat and stationary power generation. However, lean premixed flames are highly susceptible to fluid-dynamical combustion instabilities making robust and reliable systems difficult to design. Low swirl burners are emerging as an important technology for meeting design requirements in terms of both reliability and emissions for next generation combustion devices. In this paper, we present simulations of a lean, premixed hydrogen flame stabilized on a laboratory-scale low swirl burner. The simulations use detailed chemistry and transport without incorporating explicit models for turbulence or turbulence/chemistry interaction. Here we discuss the overall structure of the flame and compare with experimental data. We also use the simulation data to elucidate the characteristics of the turbulent flame interaction and how this impacts the analysis of experimental measurements.
Codd, E F
1968-01-01
Cellular Automata presents the fundamental principles of homogeneous cellular systems. This book discusses the possibility of biochemical computers with self-reproducing capability.Organized into eight chapters, this book begins with an overview of some theorems dealing with conditions under which universal computation and construction can be exhibited in cellular spaces. This text then presents a design for a machine embedded in a cellular space or a machine that can compute all computable functions and construct a replica of itself in any accessible and sufficiently large region of t
Ambekar Ramachandra Rao, Raghu
Collagen is the most abundant structural protein found in the human body, and is responsible for providing structure and function to tissues. Collagen molecules organize naturally into structures called fibers on the scale of the wavelength of light and lack inversion symmetry, thus allowing for the process of second harmonic generation (SHG) when exposed to intense incident light. We have developed two quantitative techniques: Fourier transform-second-harmonic generation (FT-SHG) imaging and generalized chi2 second-harmonic generation (chi2-SHG) imaging. In order to show that FT-SHG imaging can be used as a valuable diagnostic tool for real-world biological problems, we first investigate collagenase-induced injury in horse tendons. Clear differences in collagen fiber organization between normal and injured tendon are quantified. In particular, we observe that the regularly oriented organization of collagen fibers in normal tendons is disrupted in injured tendons leading to a more random organization. We also observe that FT-SHG microscopy is more sensitive in assessing tendon injury compared to the conventional polarized light microscopy. The second study includes quantifying collagen fibers in cortical bone using FT-SHG imaging and comparing it with scanning electron microscopy (SEM). Further, as an example study, we show how FT-SHG imaging could be used to quantify changes in bone structure as a function of age. Some initial work and future directions for extending FT-SHG to 3D are also discussed. The second technique, chi2-SHG imaging, takes advantage of the coherent nature of SHG and utilizes polarization to extract the second-order susceptibility (d elements) which provides information on molecular organization, i.e., it provides access to sub-diffractional changes "optically". We use chi2-SHG in combination with FT-SHG imaging to investigate a couple of biological problems. First, we quantify differences in collagen fiber organization between cornea and
Guisbiers, Grégory; Mendoza-Cruz, Rubén; Bazán-Díaz, Lourdes; Velázquez-Salazar, J Jesús; Mendoza-Perez, Rafael; Robledo-Torres, José Antonio; Rodriguez-Lopez, José-Luis; Montejano-Carrizales, Juan Martín; Whetten, Robert L; José-Yacamán, Miguel
2016-01-26
The alloy Au-Ag system is an important noble bimetallic phase, both historically (as "Electrum") and now especially in nanotechnology, as it is applied in catalysis and nanomedicine. To comprehend the structural characteristics and the thermodynamic stability of this alloy, a knowledge of its phase diagram is required that considers explicitly its size and shape (morphology) dependence. However, as the experimental determination remains quite challenging at the nanoscale, theoretical guidance can provide significant advantages. Using a regular solution model within a nanothermodynamic approach to evaluate the size effect on all the parameters (melting temperature, melting enthalpy, and interaction parameters in both phases), the nanophase diagram is predicted. Besides an overall shift downward, there is a "tilting" effect on the solidus-liquidus curves for some particular shapes exposing the (100) and (110) facets (cube, rhombic dodecahedron, and cuboctahedron). The segregation calculation reveals the preferential presence of silver at the surface for all the polyhedral shapes considered, in excellent agreement with the latest transmission electron microscopy observations and energy dispersive spectroscopy analysis. By reviewing the nature of the surface segregated element of different bimetallic nanoalloys, two surface segregation rules, based on the melting temperatures and surface energies, are deduced. Finally, the optical properties of Au-Ag nanoparticles, calculated within the discrete dipole approximation, show the control that can be achieved in the tuning of the local surface plasmon resonance, depending of the alloy content, the chemical ordering, the morphology, the size of the nanoparticle, and the nature of the surrounding environment. PMID:26605557
Gosálvez, M. A.; Ferrando, N.; Fedoryshyn, Y.; Leuthold, J.; McPeak, K. M.
2016-04-01
We combine experiments and simulations to study the acceleration of anisotropic etching of crystalline silicon at the mask-substrate interface, as a function of the coordination number of the substrate atoms located at the junction between obtuse-angled {1 1 1} facets and the mask layer. Atomistic simulations based on the use of the continuous cellular automaton (CCA) conclude that the interface atoms react faster with the etchant, thus initiating a step flow process that results in increased etch rates for the obtuse facets. By generating a wide range of complex cavities on high-index silicon wafers with a single-side, single-step etching, the comparison of the experimental and simulated results strongly indicates that the CCA method is suitable for accurately describing not only the development of micron-scaled structures but also, for the first time, the formation of submicron shapes. The study also describes the acceleration of obtuse facets formed through double-side etching, obtaining results in good agreement with previous experiments.
An approach to gluonium based on QCD sum rules is given. The basic idea underlying the sum rules is that asymptotic freedom is violated first by interaction of quarks and gluons with vacuum fields. Formation of resonances is a phenomenological manifestation of this interaction. The emphasis is given to a new mass scale implied by the sum rules
Gersbach, Hans; Hahn, Volker; Imhof, Stephan
2010-01-01
We examine the provision of public projects under tax and subsidy rules. We find that tax rules separated from project cum subsidy decisions exhibit several advantages when incentive problems of the agenda-setter are taken into account. In particular, tax rules may prevent the proposal of inefficient projects that benefit only a small lobby group. We propose “redistribution efficiency” as a socially desirable property of proposals and find that tax rules always guarantee this kind of efficien...
Chaotic behavior in the disorder cellular automata
Disordered cellular automata (DCA) represent an intermediate class between elementary cellular automata and the Kauffman network. Recently, Rule 126 of DCA has been explicated: the system can be accurately described by a discrete probability function. However, a means of extending to other rules has not been developed. In this investigation, a density map of the dynamical behavior of DCA is formulated based on Rule 22 and other totalistic rules. The numerical results reveal excellent agreement between the model and original automata. Furthermore, the inhomogeneous situation is also discussed
Rosenau, M.; Nerlich, R.; Brune, S.; Oncken, O.
2009-12-01
Great subduction megathrust earthquakes pose a significant tsunami risk in coastal regions. In order to constrain natural tsunamigenic source heterogeneity and its effect on tsunami variability in different subduction settings (accretive, erosive), we here analyze a sequence of experimentally simulated great megathrust earthquakes. We use an elastoplastic wedge overlying a rate- and state-dependent frictional interface as an analog model of the subduction forearc overlying a seismogenic megathrust. Near-field (local) tsunami heights are derived by means of analytical versus numerical hydrodynamic calculations from the surface deformation of the analog model in comparison to predictions of an elastic dislocation model. The cumulative slip distribution over the simulated earthquake sequence resembles widely used skewed parameterizations supporting their use in worst case scenarios. Due to body forces and strain localization, tsunamis predicted by the analog model are enriched in kinetic energy compared to EDM predictions. The tsunami height-to-slip-ratio (“Plafker rule of thumb”) and its variance scale inversely to forearc slope according to a power law from ~ 1 at accretionary to ~ 1/4 in erosive settings (Cv ~ 0.6). Tsunami height scales exponentially with earthquake magnitude, has a power-law dependence on forearc slope and a variability characterized by Cv ~ 0.5 (see Figure). In terms of predicting tsunami scale and variability the analog model outperforms the elastic dislocation model which tends to overestimate local tsunami height and underscore its variability when tested against empirical data. Based on the experimentally derived earthquake-tsunami scaling law we infer the distribution of tsunami hazard on a global scale. Because of the exponential scaling of tsunamis with earthquake magnitude, its sensitivity to forearc slope and the possible non-linear kinetic enrichment of tsunamis triggered by giant earthquakes, disaster hotspots occur preferentially
The X-ray emission mechanism of large scale powerful quasar jets: Fermi rules out IC/CMB for 3C 273.
Georganopoulos Markos
2013-12-01
Full Text Available The process responsible for the Chandra-detected X-ray emission from the large-scale jets of powerful quasars is not clear yet. The two main models are inverse Compton scattering off the cosmic microwave background photons (IC/CMB and synchrotron emission from a population of electrons separate from those producing the radio-IR emission. These two models imply radically different conditions in the large scale jet in terms of jet speed, kinetic power, and maximum energy of the particle acceleration mechanism, with important implications for the impact of the jet on the larger-scale environment. Georganopoulos et al. (2006 proposed a diagnostic based on a fundamental difference between these two models: the production of synchrotron X-rays requires multi-TeV electrons, while the EC/CMB model requires a cutoff in the electron energy distribution below TeV energies. This has significant implications for the γ-ray emission predicted by these two models. Here we present new Fermi observations that put an upper limit on the gamma-ray flux from the large-scale jet of 3C 273 that clearly violates the flux expected from the IC/CMB X-ray interpretation found by extrapolation of the UV to X-ray spectrum of knot A, thus ruling out the IC/CMB interpretation entirely for this source. Further, the upper limit from Fermi puts a limit on the Doppler beaming factor of at least δ <9, assuming equipartition fields, and possibly as low as δ <5 assuming no major deceleration of the jet from knots A through D1.
Murguia, J S
2011-01-01
We apply the WT-MFDFA, MFDFA, and WTMM methods to the time series of the row sum signals of the two complementary ECA pairs of rules (90,165) and (150,105) for ten initial conditions going from a single 1 in the central position up to a set of ten 1's covering the ten central positions in the first row. Since the members of the pairs are actually similar from the statistical point of view we can check which method is the most stable numerically by recording the differences provided by the methods between the two members of the pairs for various important quantities of the scaling analyses, such as the multifractal support, the most frequent Holder exponent, and the Hurst exponent. Our results show that the MFDFA performs better than WT-MFDFA and WTMM in the case of the multifractal support, while for the other two scaling parameters the WT-MFDFA is the best. The employed set of initial conditions does not generate any specific trend in the values of the parameters
Meyer, Eileen T; Sparks, William B; Godfrey, Leith; Lovell, James E J; Perlman, Eric
2015-01-01
The Chandra X-ray observatory has discovered dozens of resolved, kiloparsec-scale jets associated with powerful quasars in which the X-ray fluxes are observed to be much higher than the expected level based on the radio-optical synchrotron spectrum. The most popular explanation for the anomalously high and hard X-ray fluxes is that these jets do not decelerate significantly by the kiloparsec scale, but rather remain highly relativistic (Lorentz factors $\\Gamma\\approx$10). By adopting a small angle to the line-of-sight, the X-rays can thus be explained by inverse Compton upscattering of CMB photons (IC/CMB), where the observed emission is strongly Doppler boosted. Using over six years of Fermi monitoring data, we show that the expected hard, steady gamma-ray emission implied by the IC/CMB model is not seen in PKS 0637-752, the prototype jet for which this model was first proposed. IC/CMB emission is thus ruled out as the source of the X-rays, joining recent results for the jets in 3C 273 (using the same method...
On reversibility of cellular automata with periodic boundary conditions
Nobe, Atsushi [Graduate School of Engineering Science, Osaka University, Machikaneyama-cho 1-3, Toyonaka, Osaka 560-8531 (Japan); Yura, Fumitaka [Imai Quantum Computing and Information Project, ERATO, JST, Daini Hongo White Bldg 201, 5-28-3 Hongo, Bunkyo, Tokyo 113-0033 (Japan)
2004-06-04
Reversibility of one-dimensional cellular automata with periodic boundary conditions is discussed. It is shown that there exist exactly 16 reversible elementary cellular automaton rules for infinitely many cell sizes by means of a correspondence between elementary cellular automaton and the de Bruijn graph. In addition, a sufficient condition for reversibility of three-valued and two-neighbour cellular automaton is given.
Boltzmann learning of parameters in cellular neural networks
Hansen, Lars Kai
1992-01-01
The use of Bayesian methods to design cellular neural networks for signal processing tasks and the Boltzmann machine learning rule for parameter estimation is discussed. The learning rule can be used for models with hidden units, or for completely unsupervised learning. The latter is exemplified ...... unsupervised adaptation of an image segmentation cellular network. The learning rule is applied to adaptive segmentation of satellite imagery......The use of Bayesian methods to design cellular neural networks for signal processing tasks and the Boltzmann machine learning rule for parameter estimation is discussed. The learning rule can be used for models with hidden units, or for completely unsupervised learning. The latter is exemplified by...
Kumar, Shailesh
2010-01-01
A cellular automata (CA) configuration is constructed that exhibits emergent failover. The configuration is based on standard Game of Life rules. Gliders and glider-guns form the core messaging structure in the configuration. The blinker is represented as the basic computational unit, and it is shown how it can be recreated in case of a failure. Stateless failover using primary-backup mechanism is demonstrated. The details of the CA components used in the configuration and its working are described, and a simulation of the complete configuration is also presented.
Line Complexity Asymptotics of Polynomial Cellular Automata
Stone, Bertrand
2016-01-01
Cellular automata are discrete dynamical systems that consist of patterns of symbols on a grid, which change according to a locally determined transition rule. In this paper, we will consider cellular automata that arise from polynomial transition rules, where the symbols in the automaton are integers modulo some prime $p$. We are principally concerned with the asymptotic behavior of the line complexity sequence $a_T(k)$, which counts, for each $k$, the number of coefficient strings of length...
Bagnoli, Franco
1998-01-01
An introduction to cellular automata (both deterministic and probabilistic) with examples. Definition of deterministic automata, dynamical properties, damage spreading and Lyapunov exponents; probabilistic automata and Markov processes, nonequilibrium phase transitions, directed percolation, diffusion; simulation techniques, mean field. Investigation themes: life, epidemics, forest fires, percolation, modeling of ecosystems and speciation. They represent my notes for the school "Dynamical Mod...
Irregular Cellular Learning Automata.
Esnaashari, Mehdi; Meybodi, Mohammad Reza
2015-08-01
Cellular learning automaton (CLA) is a recently introduced model that combines cellular automaton (CA) and learning automaton (LA). The basic idea of CLA is to use LA to adjust the state transition probability of stochastic CA. This model has been used to solve problems in areas such as channel assignment in cellular networks, call admission control, image processing, and very large scale integration placement. In this paper, an extension of CLA called irregular CLA (ICLA) is introduced. This extension is obtained by removing the structure regularity assumption in CLA. Irregularity in the structure of ICLA is needed in some applications, such as computer networks, web mining, and grid computing. The concept of expediency has been introduced for ICLA and then, conditions under which an ICLA becomes expedient are analytically found. PMID:25291810
Generalized Multidimensional Association Rules
周傲英; 周水庚; 金文; 田增平
2000-01-01
The problem of association rule mining has gained considerable prominence in the data mining community for its use as an important tool of knowl-edge discovery from large-scale databases. And there has been a spurt of research activities around this problem. Traditional association rule mining is limited to intra-transaction. Only recently the concept of N-dimensional inter-transaction as-sociation rule (NDITAR) was proposed by H.J. Lu. This paper modifies and extends Lu's definition of NDITAR based on the analysis of its limitations, and the general-ized multidimensional association rule (GMDAR) is subsequently introduced, which is more general, flexible and reasonable than NDITAR.
Smirnova, Lena; Harris, Georgina; Leist, Marcel; Hartung, Thomas
2015-01-01
Cellular resilience describes the ability of a cell to cope with environmental changes such as toxicant exposure. If cellular metabolism does not collapse directly after the hit or end in programmed cell death, the ensuing stress responses promote a new homeostasis under stress. The processes of reverting "back to normal" and reversal of apoptosis ("anastasis") have been studied little at the cellular level. Cell types show astonishingly similar vulnerability to most toxicants, except for those that require a very specific target, metabolism or mechanism present only in specific cell types. The majority of chemicals triggers "general cytotoxicity" in any cell at similar concentrations. We hypothesize that cells differ less in their vulnerability to a given toxicant than in their resilience (coping with the "hit"). In many cases, cells do not return to the naive state after a toxic insult. The phenomena of "pre-conditioning", "tolerance" and "hormesis" describe this for low-dose exposures to toxicants that render the cell more resistant to subsequent hits. The defense and resilience programs include epigenetic changes that leave a "memory/scar" - an alteration as a consequence of the stress the cell has experienced. These memories might have long-term consequences, both positive (resistance) and negative, that contribute to chronic and delayed manifestations of hazard and, ultimately, disease. This article calls for more systematic analyses of how cells cope with toxic perturbations in the long-term after stressor withdrawal. A technical prerequisite for these are stable (organotypic) cultures and a characterization of stress response molecular networks. PMID:26536287
Mathematical Physics of Cellular Automata
Garcia-Morales, Vladimir
2012-01-01
A universal map is derived for all deterministic 1D cellular automata (CA) containing no freely adjustable parameters. The map can be extended to an arbitrary number of dimensions and topologies and its invariances allow to classify all CA rules into equivalence classes. Complexity in 1D systems is then shown to emerge from the weak symmetry breaking of the addition modulo an integer number p. The latter symmetry is possessed by certain rules that produce Pascal simplices in their time evolution. These results elucidate Wolfram's classification of CA dynamics.
47 CFR 22.917 - Emission limitations for cellular equipment.
2010-10-01
... 47 Telecommunication 2 2010-10-01 2010-10-01 false Emission limitations for cellular equipment. 22... SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.917 Emission limitations for cellular equipment. The rules in this section govern the spectral characteristics of emissions in the...
The Universe as a Cellular System
Aragón-Calvo, Miguel A
2014-01-01
Cellular systems are observed everywhere in nature, from crystal domains in metals, soap froth and cucumber cells to the network of cosmological voids. Surprisingly, despite their disparate scale and origin all cellular systems follow certain scaling laws relating their geometry, topology and dynamics. Using a cosmological N-body simulation we found that the Cosmic Web, the largest known cellular system, follows the same scaling relations seen elsewhere in nature. Our results extend the validity of scaling relations in cellular systems by over 30 orders of magnitude in scale with respect to previous studies. The dynamics of cellular systems can be used to interpret local observations such as the local velocity anomaly as the result of a collapsing void in our cosmic backyard. Moreover, scaling relations depend on the curvature of space, providing an independent measure of geometry.
Predictive Modelling of Cellular Load
Carolan, Emmett; McLoone, Seamus; Farrell, Ronan
2015-01-01
This work examines the temporal dynamics of cellular load in four Irish regions. Large scale underutilisation of network resources is identified both at the regional level and at the level of individual cells. Cellular load is modeled and prediction intervals are generated. These prediction intervals are used to put an upper bound on usage in a particular cell at a particular time. Opportunities for improvements in network utilization by incorporating these upper bounds on usage are identifie...
Christensen, Jørgen Riber
2011-01-01
climax of the masque was “Rule, Britannia!” This song advocated a strong navy as a guard against the absolutist European powers with their lack of civil liberties. Furthermore, a strong navy made a standing army superfluous, and so an army could not be deployed as a repressive force of the state. Later a...
Abelin, Jennifer G; Patel, Jinal; Lu, Xiaodong; Feeney, Caitlin M; Fagbami, Lola; Creech, Amanda L; Hu, Roger; Lam, Daniel; Davison, Desiree; Pino, Lindsay; Qiao, Jana W; Kuhn, Eric; Officer, Adam; Li, Jianxue; Abbatiello, Susan; Subramanian, Aravind; Sidman, Richard; Snyder, Evan; Carr, Steven A; Jaffe, Jacob D
2016-05-01
Profiling post-translational modifications represents an alternative dimension to gene expression data in characterizing cellular processes. Many cellular responses to drugs are mediated by changes in cellular phosphosignaling. We sought to develop a common platform on which phosphosignaling responses could be profiled across thousands of samples, and created a targeted MS assay that profiles a reduced-representation set of phosphopeptides that we show to be strong indicators of responses to chemical perturbagens.To develop the assay, we investigated the coordinate regulation of phosphosites in samples derived from three cell lines treated with 26 different bioactive small molecules. Phosphopeptide analytes were selected from these discovery studies by clustering and picking 1 to 2 proxy members from each cluster. A quantitative, targeted parallel reaction monitoring assay was developed to directly measure 96 reduced-representation probes. Sample processing for proteolytic digestion, protein quantification, peptide desalting, and phosphopeptide enrichment have been fully automated, making possible the simultaneous processing of 96 samples in only 3 days, with a plate phosphopeptide enrichment variance of 12%. This highly reproducible process allowed ∼95% of the reduced-representation phosphopeptide probes to be detected in ∼200 samples.The performance of the assay was evaluated by measuring the probes in new samples generated under treatment conditions from discovery experiments, recapitulating the observations of deeper experiments using a fraction of the analytical effort. We measured these probes in new experiments varying the treatments, cell types, and timepoints to demonstrate generalizability. We demonstrated that the assay is sensitive to disruptions in common signaling pathways (e.g. MAPK, PI3K/mTOR, and CDK). The high-throughput, reduced-representation phosphoproteomics assay provides a platform for the comparison of perturbations across a range of
Knowledge discovery for geographical cellular automata
LI; Xia; Anthony; Gar-On; Yeh
2005-01-01
This paper proposes a new method for geographical simulation by applying data mining techniques to cellular automata. CA has strong capabilities in simulating complex systems. The core of CA is how to define transition rules. There are no good methods for defining these transition rules. They are usually defined by using heuristic methods and thus subject to uncertainties. Mathematical equations are used to represent transition rules implicitly and have limitations in capturing complex relationships. This paper demonstrates that the explicit transition rules of CA can be automatically reconstructed through the rule induction procedure of data mining. The proposed method can reduce the influences of individual knowledge and preferences in defining transition rules and generate more reliable simulation results. It can efficiently discover knowledge from a vast volume of spatial data.
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Other information as of 2003. It is described as 'Cell...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Published Reports/Deeds information as of 2011. It is...
NSGIC GIS Inventory (aka Ramona) — This Cellular Phone Towers dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Other information as of 2003. It is described as 'FCC...
Chen, Zhe
2015-01-01
Emerging technologies, such as big data, Internet of things, cloud computing, mobile Internet, and robotics, breed and expedite new applications and fields. In the mean while, the long-term prosperity and happiness of human race demands advanced technologies. In this paper, the aforementioned emerging technologies are applied to management and governance for the long-term prosperity and happiness of human race. The term "machine ruling" is coined, introduced, and justified. Moreover, the fram...
Porod, Wolfgang; Lent, Craig S.; Bernstein, Gary H.
1994-06-01
The Notre Dame group has developed a new paradigm for ultra-dense and ultra-fast information processing in nanoelectronic systems. These Quantum Cellular Automata (QCA's) are the first concrete proposal for a technology based on arrays of coupled quantum dots. The basic building block of these cellular arrays is the Notre Dame Logic Cell, as it has been called in the literature. The phenomenon of Coulomb exclusion, which is a synergistic interplay of quantum confinement and Coulomb interaction, leads to a bistable behavior of each cell which makes possible their use in large-scale cellular arrays. The physical interaction between neighboring cells has been exploited to implement logic functions. New functionality may be achieved in this fashion, and the Notre Dame group invented a versatile majority logic gate. In a series of papers, the feasibility of QCA wires, wire crossing, inverters, and Boolean logic gates was demonstrated. A major finding is that all logic functions may be integrated in a hierarchial fashion which allows the design of complicated QCA structures. The most complicated system which was simulated to date is a one-bit full adder consisting of some 200 cells. In addition to exploring these new concepts, efforts are under way to physically realize such structures both in semiconductor and metal systems. Extensive modeling work of semiconductor quantum dot structures has helped identify optimum design parameters for QCA experimental implementations.
Tortolina, L; Castagnino, N; De Ambrosi, C; Moran, E; Patrone, F; Ballestrero, A; Parodi, S
2012-05-01
This review article is part of a special Current Cancer Drug Targets issue devoted to colorectal cancer and molecularly targeted treatments. In our paper we made an attempt to connect more basic aspects with preclinical, pharmacological / therapeutic and clinical aspects. Reconstruction of a Molecular Interaction Map (MIM) comprising an important part of the G0 - G1 - S cell cycle transition, was a major component of our review. Such a MIM serves also as a convenient / organized database of a large set of important molecular events. The frequency of mutated / altered signaling-proteins indicates the importance of this signaling-network region. We have considered problems at different scale levels. Our MIM works at a biochemical-interaction level. We have also touched the multi-cellular dynamics of normal and aberrant colon crypts. Until recently, dynamic simulations at a biochemical or multi-cellular scale level were considered as a sort of esoteric approach. We tried to convince the reader, also on the basis of a rapidly growing literature, mostly published in high quality journals, that suspicion towards simulations should dissipate, as the limitations and advantages of their application are better appreciated, opening the door to their permanent adoption in everyday research. What is really required is a more interdisciplinary mentality and an interdisciplinary approach. The prize is a level of understanding going beyond mere intuition. PMID:22385511
Chen, Hong; Yang, Ping; Chu, Xiaoya; Huang, Yufei; Liu, Tengfei; Zhang, Qian; Li, Quanfu; Hu, Lisi; Waqas, Yasir; Ahmed, Nisar; Chen, Qiusheng
2016-01-01
The epididymis is the location of sperm maturation and sperm storage. Recent studies have shown that nano-scale exosomes play a vital role during these complicated processes. Our aim was to analyze the secretory properties of epididymal exosomes and their ultrastructural interaction with maturing spermatozoa in the Chinese soft-shelled turtle. The exosome marker CD63 was primarily localized to the apices of principal cells throughout the epididymal epithelium. Identification of nano-scale exosomes and their secretory processes were further investigated via transmission electron microscopy. The epithelium secreted epididymal exosomes (50~300 nm in diameter) through apocrine secretion and the multivesicular body (MVB) pathway. Spermatozoa absorbed epididymal exosomes through endocytosis or membrane fusion pathways. This study shows, for the first time, that nano-scale exosomes use two secretion and two absorption pathways in the reptile, which may be contribute to long-term sperm storage. PMID:26992236
Origami interleaved tube cellular materials
A novel origami cellular material based on a deployable cellular origami structure is described. The structure is bi-directionally flat-foldable in two orthogonal (x and y) directions and is relatively stiff in the third orthogonal (z) direction. While such mechanical orthotropicity is well known in cellular materials with extruded two dimensional geometry, the interleaved tube geometry presented here consists of two orthogonal axes of interleaved tubes with high interfacial surface area and relative volume that changes with fold-state. In addition, the foldability still allows for fabrication by a flat lamination process, similar to methods used for conventional expanded two dimensional cellular materials. This article presents the geometric characteristics of the structure together with corresponding kinematic and mechanical modeling, explaining the orthotropic elastic behavior of the structure with classical dimensional scaling analysis. (paper)
Tinbergen Rules the Taylor Rule
Thomas R. Michl
2008-01-01
This paper elaborates a simple model of growth with a Taylor-like monetary policy rule that includes inflation-targeting as a special case. When the inflation process originates in the product market, inflation-targeting locks in the unemployment rate prevailing at the time the policy matures. Although there is an apparent NAIRU and Phillips curve, this long-run position depends on initial conditions; in the presence of stochastic shocks, it would be path dependent. Even with an employment ta...
Aktay, Metin
2000-01-01
Goldbach`s Conjecture, "every even number greater than 2 can be expressed as the sum of two primes" is renamed Goldbach`s Rule for it can not be otherwise. The conjecture is proven by showing that the existence of prime pairs adding to any even number greater than 2 is a natural by-product of the existence of the prime sequence less than that even number. First it is shown that the remainder of cancellations process which identifies primes less than an even number also remainders prime pairs ...
Weaver, E R; Pickering, S F
1924-01-01
This report prepared for the National Advisory Committee for Aeronautics, describes an airship slide rule developed by the Gas-Chemistry Section of the Bureau of Standards, at the request of the Bureau of Engineering of the Navy Department. It is intended primarily to give rapid solutions of a few problems of frequent occurrence in airship navigation, but it can be used to advantage in solving a great variety of problems, involving volumes, lifting powers, temperatures, pressures, altitudes and the purity of the balloon gas. The rule is graduated to read directly in the units actually used in making observations, constants and conversion factors being taken care of by the length and location of the scales. It is thought that with this rule practically any problem likely to arise in this class of work can be readily solved after the user has become familiar with the operation of the rule; and that the solution will, in most cases, be as accurate as the data warrant.
Computing by Temporal Order: Asynchronous Cellular Automata
Michael Vielhaber
2012-08-01
Full Text Available Our concern is the behaviour of the elementary cellular automata with state set 0,1 over the cell set Z/nZ (one-dimensional finite wrap-around case, under all possible update rules (asynchronicity. Over the torus Z/nZ (n<= 11,we will see that the ECA with Wolfram rule 57 maps any v in F_2^n to any w in F_2^n, varying the update rule. We furthermore show that all even (element of the alternating group bijective functions on the set F_2^n = 0,...,2^n-1, can be computed by ECA57, by iterating it a sufficient number of times with varying update rules, at least for n <= 10. We characterize the non-bijective functions computable by asynchronous rules.
Probing Cellular Dynamics with Mesoscopic Simulations
Shillcock, Julian C.
2010-01-01
Cellular processes span a huge range of length and time scales from the molecular to the near-macroscopic. Understanding how effects on one scale influence, and are themselves influenced by, those on lower and higher scales is a critical issue for the construction of models in Systems Biology....... Advances in computing hardware and software now allow explicit simulation of some aspects of cellular dynamics close to the molecular scale. Vesicle fusion is one example of such a process. Experiments, however, typically probe cellular behavior from the molecular scale up to microns. Standard particle...... soon be coupled to Mass Action models allowing the parameters in such models to be continuously tuned according to the finer resolution simulation. This will help realize the goal of a computational cellular simulation that is able to capture the dynamics of membrane-associated processes such as...
Cellular structure in system of interacting particles
Lev, Bohdan
2008-01-01
The general description of formation the cellular structure in the system of interacting particles is proposed. Interactions between particles are presumably well-understood and the phase transition in which can be studied in the scale of particle resolution. We presented analytical results of possible cellular structures for suspension of colloidal particles, in system particles immersed in liquid crystal and gravitational system. We have shown that cellular structure formation can occur in ...
Engineering Cellular Metabolism
Nielsen, Jens; Keasling, Jay
2016-01-01
Metabolic engineering is the science of rewiring the metabolism of cells to enhance production of native metabolites or to endow cells with the ability to produce new products. The potential applications of such efforts are wide ranging, including the generation of fuels, chemicals, foods, feeds......, and pharmaceuticals. However, making cells into efficient factories is challenging because cells have evolved robust metabolic networks with hard-wired, tightly regulated lines of communication between molecular pathways that resist efforts to divert resources. Here, we will review the current status and challenges...... of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation....
Recursive definition of global cellular-automata mappings
Feldberg, Rasmus; Knudsen, Carsten; Rasmussen, Steen
1994-01-01
as the number of lattice sites is incremented. A proof of lattice size invariance of global cellular-automata mappings is derived from an approximation to the exact recursive definition. The recursive definitions are applied to calculate the fractal dimension of the set of reachable states and of the set......A method for a recursive definition of global cellular-automata mappings is presented. The method is based on a graphical representation of global cellular-automata mappings. For a given cellular-automaton rule the recursive algorithm defines the change of the global cellular-automaton mapping...
Fermi Rules Out the IC/CMB Model for the Large Scale Jet X-ray Emission of 3C 273
Meyer, Eileen T.; Georganopoulos, Markos
2013-01-01
The X-ray emission mechanism in large-scale jets of powerful radio quasars has been a source of debate in recent years, with two competing interpretations: either the X-rays are of synchrotron origin, arising from a different electron energy distribution than that producing the radio to optical synchrotron component, or they are due to inverse Compton scattering of cosmic microwave background photons (IC/CMB) by relativistic electrons in a powerful relativistic jet with bulk Lorentz factor Ga...
The Consensus Problem, Cellular Automata, and Self- replicating Structures
Griffin, David
2016-01-01
Over The course of the last four years I have researched the consensus problem. I have done so by studying how cellular automata following the 2DGKL rule are able to reach consensus in a verity of ways. There are only certain structures that can form within a network, and these structures can be described and examined directly from the rules that make them up. I have also explored a variety of methods to study the rule including, graph theory and liner algebra representations of the cellular ...
Cellular Dynamics of RNA Modification
Yi, Chengqi; Pan, Tao
2011-01-01
Decades of research have identified over 100 types of ribonucleosides that are post-transcriptionally modified. Many modified nucleosides are conserved in bacteria, archeae and eukaryotes, while some modified nucleosides are unique to each branch of life. However, the cellular and functional dynamics of RNA modifications remains largely unexplored, mostly due to the lack of functional hypotheses and experimental methods for quantification and large scale analysis. Just as many well characteri...
Mechanical oscillations at the cellular scale
Jülicher, F
2001-01-01
Active phenomena which involve force generation and motion play a key role in a number of phenomena in living cells such as cell motility, muscle contraction and the active transport of material and organelles. Here we discuss mechanical oscillations generated by active systems in cells. Examples are oscillatory regimes in muscles, the periodic beating of axonemal cilia and flagella and spontaneous oscillations of auditory hair cells which play a role in active amplification of weak sounds in hearing. As a prototype system for oscillation generation by proteins, we discuss a general mechanism by which many coupled active elements such as motor molecules can generate oscillations.
Atilla ÖZMEN
2000-01-01
Full Text Available In this paper, Segmented Cellular Neural Network-Cellular Neural Network Combined Trellis Coded Quantization / Modulation (SCNN-CNN CTCQ/TCM scheme is introduced. Here, a gray scaled image is lowered to 3 bit using our proposed Segmented Cellular Neural Network approach (SCNN and then passed through a new CNN based structure which models combined trellis coded quantization / modulation. The performance of our combined scheme has been analyzed over Rician fading channel. Computer simulations studies confirm the analytical upper bound curves.
A large experimental and modeling activity is currently taking place, aimed at better understanding the biological effects of ionizing radiation at the molecular scales. Considerable amounts of experimental data have been accumulated over the past decades in order to measure quantities such as macroscopic cellular survival curves and DNA strand damages after irradiation. In parallel, computer codes have been proposed to use a stochastic approach based on Monte Carlo technique to model physical interaction in the irradiated medium. The Geant4 tool-kit uses the object-oriented technology (C++) to describing particle-matter interactions, such as bio-medical physics and space physics, from sub-micrometer cells up to planetary scales. Geant4-DNA project is included in the Geant4 tool-kit and benefits from the easy accessibility of the Geant4 code for the development of a computing platform allowing estimation effects of ionizing radiations. In my thesis, firstly, I have contributed in the project the validation of various models with the experimental data collections extracted from the recent literature. A good agreement between total and differential cross section values corresponding to each available Geant4-DNA model and experimental data is validated by Kolmogorov-Smirnov testing. Secondly, I have improved elastic scattering process and working on the calculation of the DDCS for proton elastic scattering in water in the Geant4-DNA. In addition, I have combined Geant4 electromagnetic processes with the Geant4-DNA. This combination brought additional Geant4 simulation capabilities in complement of the possibility to combine Geant4-DNA models with other Geant4 electromagnetic models at different sizes and energy scales in a single simulation application. Finally, we have presented the usage of Geant4-DNA physics processes in Nano-meter-size targets fully implemented in a single Geant4 application. The frequencies of the deposited energy and number of direct DNA single
Mould, Richard A
2004-01-01
Quantum mechanics traditionally places the observer outside of the system being studied and employs the Born interpretation. In this and related papers the observer is placed inside the system. To accomplish this, special rules are required to engage and interpret the Schrodinger solutions in individual measurements. The rules in this paper (called the nRules) do not include the Born rule that connects probability with square modulus. It is required that the rules allow all conscious observer...
Nanomechanics of magnetically driven cellular endocytosis
Zablotskii, V.; Lunov, O.; Dejneka, A.; Jastrabík, L.; Polyakova, T.; Syrovets, T.; Simmet, Th.
2011-10-01
Being essential for many pharmacodynamic and pharmacokinetic processes and playing a crucial role in regulating substrate detachment that enables cellular locomotion, endocytotic mechanisms in many aspects still remain a mystery and therefore can hardly be controlled. Here, we report on experimental and modeling studies of the magnetically assisted endocytosis of functionalized superparamagnetic iron oxide nanoparticles by prostate cancer cells (PC-3) and characterize the time and force scales of the cellular uptake machinery. The results indicate how the cellular uptake rate could be controlled by applied magnetic field, membrane elasticity, and nanoparticle magnetic moment.
Keiding, Hans; Peleg, Bezalel
2006-01-01
Abstract A social choice rule (SCR) is a collection of social choice correspondences, one for each agenda. An effectivity rule is a collection of effectivity functions, one for each agenda. We prove that every monotonic and superadditive effectivity rule is the effectivity rule of some SCR. A SCR...... is binary if it is rationalized by an acyclic binary relation. The foregoing result motivates our definition of a binary effectivity rule as the effectivity rule of some binary SCR. A binary SCR is regular if it satisfies unanimity, monotonicity, and independence of infeasible alternatives. A binary...... effectivity rule is regular if it is the effectivity rule of some regular binary SCR. We characterize completely the family of regular binary effectivity rules. Quite surprisingly, intrinsically defined von Neumann-Morgenstern solutions play an important role in this characterization...
Rule-Based Network Service Provisioning
Rudy Deca
2012-10-01
Full Text Available Due to the unprecedented development of networks, manual network service provisioning is becoming increasingly risky, error-prone, expensive, and time-consuming. To solve this problem,rule-based methods can provide adequate leverage for automating various network management tasks. This paper presents a rule-based solution for automated network service provisioning. The proposed approach captures configuration data interdependencies using high-level, service-specific, user-configurable rules. We focus on the service validation task, which is illustrated by means of a case study.Based on numerical results, we analyse the influence of the network-level complexity factors and rule descriptive features on the rule efficiency. This analysis shows the operators how to increase rule efficiency while keeping the rules simple and the rule set compact. We present a technique that allows operators to increase the error coverage, and we show that high error coverage scales well when the complexity of networks and services increases.We reassess the correlation function between specific rule efficiency and rule complexity metrics found in previous work, and show that this correlation function holds for various sizes, types, and complexities of networks and services.
Endy, Drew; Brent, Roger
2001-01-01
Representations of cellular processes that can be used to compute their future behaviour would be of general scientific and practical value. But past attempts to construct such representations have been disappointing. This is now changing. Increases in biological understanding combined with advances in computational methods and in computer power make it possible to foresee construction of useful and predictive simulations of cellular processes.
Phonological reduplication in sign language: rules rule
Iris eBerent
2014-06-01
Full Text Available Productivity—the hallmark of linguistic competence—is typically attributed to algebraic rules that support broad generalizations. Past research on spoken language has documented such generalizations in both adults and infants. But whether algebraic rules form part of the linguistic competence of signers remains unknown. To address this question, here we gauge the generalization afforded by American Sign Language (ASL. As a case study, we examine reduplication (X→XX—a rule that, inter alia, generates ASL nouns from verbs. If signers encode this rule, then they should freely extend it to novel syllables, including ones with features that are unattested in ASL. And since reduplicated disyllables are preferred in ASL, such rule should favor novel reduplicated signs. Novel reduplicated signs should thus be preferred to nonreduplicative controls (in rating, and consequently, such stimuli should also be harder to classify as nonsigns (in the lexical decision task. The results of four experiments support this prediction. These findings suggest that the phonological knowledge of signers includes powerful algebraic rules. The convergence between these conclusions and previous evidence for phonological rules in spoken language suggests that the architecture of the phonological mind is partly amodal.
Cosmological diagrammatic rules
B. Giddings, Steven; Sloth, Martin Snoager
2010-01-01
A simple set of diagrammatic rules is formulated for perturbative evaluation of ``in-in" correlators, as is needed in cosmology and other nonequilibrium problems. These rules are both intuitive, and efficient for calculational purposes....
Heterogeneous cellular networks
Hu, Rose Qingyang
2013-01-01
A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses, covering the related topics including scenarios of heterogeneous network deployment, interference management i
Romanofsky, Robert R.
2010-01-01
The cellular reflectarray antenna is intended to replace conventional parabolic reflectors that must be physically aligned with a particular satellite in geostationary orbit. These arrays are designed for specified geographical locations, defined by latitude and longitude, each called a "cell." A particular cell occupies nominally 1,500 square miles (3,885 sq. km), but this varies according to latitude and longitude. The cellular reflectarray antenna designed for a particular cell is simply positioned to align with magnetic North, and the antenna surface is level (parallel to the ground). A given cellular reflectarray antenna will not operate in any other cell.
Genetic Algorithm Calibration of Probabilistic Cellular Automata for Modeling Mining Permit Activity
Louis, S.J.; Raines, G.L.
2003-01-01
We use a genetic algorithm to calibrate a spatially and temporally resolved cellular automata to model mining activity on public land in Idaho and western Montana. The genetic algorithm searches through a space of transition rule parameters of a two dimensional cellular automata model to find rule parameters that fit observed mining activity data. Previous work by one of the authors in calibrating the cellular automaton took weeks - the genetic algorithm takes a day and produces rules leading to about the same (or better) fit to observed data. These preliminary results indicate that genetic algorithms are a viable tool in calibrating cellular automata for this application. Experience gained during the calibration of this cellular automata suggests that mineral resource information is a critical factor in the quality of the results. With automated calibration, further refinements of how the mineral-resource information is provided to the cellular automaton will probably improve our model.
Computation of bankruptcy rules
Saavedra, Verónica; Lopez, Marcelo; Necco, Claudia Mónica; Quintas, Luis Guillermo
2003-01-01
We implemented a system that computes bankruptcy rules. The implemented rules are: The Talmud, the Proportional, the Truncated Proportional, the Adjusted Proportional, the Constrained Equal Awards and the Random Arrival rule. The system computes, compares and graphics the different allocations to claimants. We present some applications and examples exported by the system.
Stiell, I.
1996-01-01
The Ottawa ankle rule project demonstrated that more than 95% of patients with ankle injuries had radiographic examinations but that 85% of the films showed no fractures. A group of Ottawa emergency physicians developed two rules to identify clinically important fractures of the malleoli and the midfoot. Use of these rules reduced radiographic examinations by 28% for the ankle and 14% for the foot.
Scaling up: Distributed machine learning with cooperation
Provost, F.J. [NYNEX Science & Technology, White Plains, NY (United States); Hennessy, D.N. [Univ. of Pittsburgh, PA (United States)
1996-12-31
Machine-learning methods are becoming increasingly popular for automated data analysis. However, standard methods do not scale up to massive scientific and business data sets without expensive hardware. This paper investigates a practical alternative for scaling up: the use of distributed processing to take advantage of the often dormant PCs and workstations available on local networks. Each workstation runs a common rule-learning program on a subset of the data. We first show that for commonly used rule-evaluation criteria, a simple form of cooperation can guarantee that a rule will look good to the set of cooperating learners if and only if it would look good to a single learner operating with the entire data set. We then show how such a system can further capitalize on different perspectives by sharing learned knowledge for significant reduction in search effort. We demonstrate the power of the method by learning from a massive data set taken from the domain of cellular fraud detection. Finally, we provide an overview of other methods for scaling up machine learning.
Cellular Dynamics of RNA Modification
Yi, Chengqi; Pan, Tao
2011-01-01
Conspectus Decades of research have identified over 100 types of ribonucleosides that are post-transcriptionally modified. Many modified nucleosides are conserved in bacteria, archeae and eukaryotes, while some modified nucleosides are unique to each branch of life. However, the cellular and functional dynamics of RNA modifications remains largely unexplored, mostly due to the lack of functional hypotheses and experimental methods for quantification and large scale analysis. Just as many well characterized protein and DNA modifications, many RNA modifications are not essential for life. Instead, increasingly more evidence indicates that RNA modifications can play regulatory roles in cells, especially in response to stress conditions. In this Account, we review some known examples of RNA modifications that are dynamically controlled in cells and introduce some contemporary technologies and methods that enhance the studies of cellular dynamics of RNA modifications. Examples of RNA modifications discussed in this Account include (Figure 1): (1) 4-thio uridine (s4U) which can act as a cellular sensor of near UV-light; (2) queuosine (Q) which is a potential biomarker for malignancy; (3) N6-methyl adenine (m6A) which is the prevalent modification in eukaryotic mRNAs; and (4) pseudouridine (ψ) which are inducible by nutrient deprivation. Two recent technical advances that stimulated the studies of cellular dynamics of modified ribonucleosides are also described. First, a genome-wide method combines primer extension and microarray to study N1-methyl adenine (m1A) hypomodification in human tRNA. Second, a quantitative mass spectrometric method investigates dynamic changes of a wide range of tRNA modifications under stress conditions in yeast. In addition, we discuss potential mechanisms that control dynamic regulation of RNA modifications, and hypotheses for discovering potential RNA de-modification enzymes. We conclude the Account by highlighting the need to develop new
Cellular oncogenes in neoplasia.
Chan, V T; McGee, J O
1987-01-01
In recent years cellular homologues of many viral oncogenes have been identified. As these genes are partially homologous to viral oncogenes and are activated in some tumour cell lines they are termed "proto-oncogenes". In tumour cell lines proto-oncogenes are activated by either quantitative or qualitative changes in gene structure: activation of these genes was originally thought to be a necessary primary event in carcinogenesis, but activated cellular oncogenes, unlike viral oncogenes, do ...
Cellular Cardiomyoplasty: Clinical Application
Chachques, J. (J.); Acar, C; J. Herreros; Trainini, J. (Jorge); Prosper, F.; D’Attellis, N. (N.); Fabiani, J. N.; Carpentier, A
2004-01-01
Myocardial regeneration can be induced with the implantation of a variety of myogenic and angiogenic cell types. More than 150 patients have been treated with cellular cardiomyoplasty worldwide, 18 patients have been treated by our group. Cellular cardiomyoplasty seems to reduce the size and fibrosis of infarct scars, limit postischemic remodelling, and restore regional myocardial contractility. Techniques for skeletal myoblasts culture and ex vivo expansion using auto...
Early object rule acquisition.
Pierce, D E
1991-05-01
The purpose of this study was to generate a grounded theory of early object rule acquisition. The grounded theory approach and computer coding were used to analyze videotaped samples of an infant's and a toddler's independent object play, which produced the categories descriptive of three primary types of object rules; rules of object properties, rules of object action, and rules of object affect. This occupational science theory offers potential for understanding the role of objects in human occupations, for development of instruments, and for applications in occupational therapy early intervention. PMID:2048625
Safety Commission
2008-01-01
The revision of CERN Safety rules is in progress and the following new Safety rules have been issued on 15-04-2008: Safety Procedure SP-R1 Establishing, Updating and Publishing CERN Safety rules: http://cern.ch/safety-rules/SP-R1.htm; Safety Regulation SR-S Smoking at CERN: http://cern.ch/safety-rules/SR-S.htm; Safety Regulation SR-M Mechanical Equipment: http://cern.ch/safety-rules/SR-M.htm; General Safety Instruction GSI-M1 Standard Lifting Equipment: http://cern.ch/safety-rules/GSI-M1.htm; General Safety Instruction GSI-M2 Standard Pressure Equipment: http://cern.ch/safety-rules/GSI-M2.htm; General Safety Instruction GSI-M3 Special Mechanical Equipment: http://cern.ch/safety-rules/GSI-M3.htm. These documents apply to all persons under the Director General’s authority. All Safety rules are available at the web page: http://www.cern.ch/safety-rules The Safety Commission
Dardzinska, Agnieszka
2013-01-01
We are surrounded by data, numerical, categorical and otherwise, which must to be analyzed and processed to convert it into information that instructs, answers or aids understanding and decision making. Data analysts in many disciplines such as business, education or medicine, are frequently asked to analyze new data sets which are often composed of numerous tables possessing different properties. They try to find completely new correlations between attributes and show new possibilities for users. Action rules mining discusses some of data mining and knowledge discovery principles and then describe representative concepts, methods and algorithms connected with action. The author introduces the formal definition of action rule, notion of a simple association action rule and a representative action rule, the cost of association action rule, and gives a strategy how to construct simple association action rules of a lowest cost. A new approach for generating action rules from datasets with numerical attributes...
A Parallel Encryption Algorithm for Block Ciphers Based on Reversible Programmable Cellular Automata
Das, Debasis
2010-01-01
A Cellular Automata (CA) is a computing model of complex System using simple rule. In CA the problem space into number of cell and each cell can be one or several final state. Cells are affected by neighbours' to the simple rule. Cellular Automata are highly parallel and discrete dynamical systems, whose behaviour is completely specified in terms of a local relation. This paper deals with the Cellular Automata (CA) in cryptography for a class of Block Ciphers through a new block encryption algorithm based on Reversible Programmable Cellular Automata Theory. The proposed algorithm belongs to the class of symmetric key systems.
Mapping functional connectivity in cellular networks
Buibas, Marius
2011-01-01
My thesis is a collection of theoretical and practical techniques for mapping functional or effective connectivity in cellular neuronal networks, at the cell scale. This is a challenging scale to work with, primarily because of the difficulty in labeling and measuring the activities of networks of cells. It is also important as it underlies behavior, function, and complex diseases. I present methods to measure and quantify the dynamic activities of cells using the optical flow technique, whic...
Cellular automata and self-organized criticality
Creutz, Michael
1996-01-01
Cellular automata provide a fascinating class of dynamical systems capable of diverse complex behavior. These include simplified models for many phenomena seen in nature. Among other things, they provide insight into self-organized criticality, wherein dissipative systems naturally drive themselves to a critical state with important phenomena occurring over a wide range of length and time scales.
Measuring interesting rules in Characteristic rule
Warnars, Spits
2010-01-01
Finding interesting rule in the sixth strategy step about threshold control on generalized relations in attribute oriented induction, there is possibility to select candidate attribute for further generalization and merging of identical tuples until the number of tuples is no greater than the threshold value, as implemented in basic attribute oriented induction algorithm. At this strategy step there is possibility the number of tuples in final generalization result still greater than threshold value. In order to get the final generalization result which only small number of tuples and can be easy to transfer into simple logical formula, the seventh strategy step about rule transformation is evolved where there will be simplification by unioning or grouping the identical attribute. Our approach to measure interesting rule is opposite with heuristic measurement approach by Fudger and Hamilton where the more complex concept hierarchies, more interesting results are likely to be found, but our approach the simple...
Page, Don N
2009-01-01
The Born rule may be stated mathematically as the rule that probabilities in quantum theory are expectation values of a complete orthogonal set of projection operators. This rule works for single laboratory settings in which the observer can distinguish all the different possible outcomes corresponding to the projection operators. However, theories of inflation suggest that the universe may be so large that any laboratory, no matter how precisely it is defined by its internal state, may exist in a large number of very distantly separated copies throughout the vast universe. In this case, no observer within the universe can distinguish all possible outcomes for all copies of the laboratory. Then normalized probabilities for the local outcomes that can be locally distinguished cannot be given by the expectation values of any projection operators. Thus the Born rule dies and must be replaced by another rule for observational probabilities in cosmology. The freedom of what this new rule is to be is the measure pr...
Mould, R A
2004-01-01
Quantum mechanics traditionally places the observer outside of the system being studied and employs the Born interpretation. In this and related papers the observer is placed inside the system. To accomplish this, special rules are required to engage and interpret the Schrodinger solutions in individual measurements. The rules in this paper (called the nRules) do not include the Born rule that connects probability with square modulus. It is required that the rules allow all conscious observers to exist inside the system without empirical ambiguity, reflecting our own unambiguous experience in the universe. This requirement is satisfied by the nRules. They allow both objective and observer measurements, so state reduction can occur with or without an observer being present. Keywords: brain states, consciousness, decoherence, epistemology, measurement, ontology, stochastic, state reduction, wave collapse.
Architected Cellular Materials
Schaedler, Tobias A.; Carter, William B.
2016-07-01
Additive manufacturing enables fabrication of materials with intricate cellular architecture, whereby progress in 3D printing techniques is increasing the possible configurations of voids and solids ad infinitum. Examples are microlattices with graded porosity and truss structures optimized for specific loading conditions. The cellular architecture determines the mechanical properties and density of these materials and can influence a wide range of other properties, e.g., acoustic, thermal, and biological properties. By combining optimized cellular architectures with high-performance metals and ceramics, several lightweight materials that exhibit strength and stiffness previously unachievable at low densities were recently demonstrated. This review introduces the field of architected materials; summarizes the most common fabrication methods, with an emphasis on additive manufacturing; and discusses recent progress in the development of architected materials. The review also discusses important applications, including lightweight structures, energy absorption, metamaterials, thermal management, and bioscaffolds.
Cellular Homeostasis and Aging.
Hartl, F Ulrich
2016-06-01
Aging and longevity are controlled by a multiplicity of molecular and cellular signaling events that interface with environmental factors to maintain cellular homeostasis. Modulation of these pathways to extend life span, including insulin-like signaling and the response to dietary restriction, identified the cellular machineries and networks of protein homeostasis (proteostasis) and stress resistance pathways as critical players in the aging process. A decline of proteostasis capacity during aging leads to dysfunction of specific cell types and tissues, rendering the organism susceptible to a range of chronic diseases. This volume of the Annual Review of Biochemistry contains a set of two reviews addressing our current understanding of the molecular mechanisms underlying aging in model organisms and humans. PMID:27050288
Wireless Cellular Mobile Communications
V. Zalud
2002-12-01
Full Text Available In this article is briefly reviewed the history of wireless cellularmobile communications, examined the progress in current secondgeneration (2G cellular standards and discussed their migration to thethird generation (3G. The European 2G cellular standard GSM and itsevolution phases GPRS and EDGE are described somewhat in detail. Thethird generation standard UMTS taking up on GSM/GPRS core network andequipped with a new advanced access network on the basis of codedivision multiple access (CDMA is investigated too. A sketch of theperspective of mobile communication beyond 3G concludes this article.
An important source of knowledge for technical experts is the state of the art reflected by catalogues of technical rules. Technical rules may also achieve importance in law due to a legal transformation standard. Here, rigid and flexible reference are controversial with regard to their admissibility from the point of view of constitutional law. In case of a divergence from the generally accepted technical rules, it is assumed - refutably - that the necessary care had not been taken. Technical rules are one out of several sources of information; they have no normative effect. This may result in a duty of anyone applying them to review the state of technology himself. (orig.)
Particles and Patterns in Cellular Automata
This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Our objective has been to develop tools for studying particle interactions in a class of dynamical systems characterized by discreteness, determinism, local interaction, and an inherently parallel form of evolution. These systems can be described by cellular automata (CA) and the behavior we studied has improved our understanding of the nature of patterns generated by CAs, their ability to perform global computations, and their relationship to continuous dynamical systems. We have also developed a rule-table mathematics that enables one to custom-design CA rule tables to generate patterns of specified types, or to perform specified computational tasks
Modeling diffusion of innovations with probabilistic cellular automata
Boccara, Nino; Fuks, Henryk
1997-01-01
We present a family of one-dimensional cellular automata modeling the diffusion of an innovation in a population. Starting from simple deterministic rules, we construct models parameterized by the interaction range and exhibiting a second-order phase transition. We show that the number of individuals who eventually keep adopting the innovation strongly depends on connectivity between individuals.
Boolean linear differential operators on elementary cellular automata
Martín Del Rey, Ángel
2014-12-01
In this paper, the notion of boolean linear differential operator (BLDO) on elementary cellular automata (ECA) is introduced and some of their more important properties are studied. Special attention is paid to those differential operators whose coefficients are the ECA with rule numbers 90 and 150.
Translating partitioned cellular automata into classical type cellular automata
Poupet, Victor
2008-01-01
Partitioned cellular automata are a variant of cellular automata that was defined in order to make it very simple to create complex automata having strong properties such as number conservation and reversibility (which are often difficult to obtain on cellular automata). In this article we show how a partitioned cellular automaton can be translated into a regular cellular automaton in such a way that these properties are conserved.
A Cellular Automata Model for the Study of Landslides
Liucci, Luisa; Suteanu, Cristian; Melelli, Laura
2016-04-01
Power-law scaling has been observed in the frequency distribution of landslide sizes in many regions of the world, for landslides triggered by different factors, and in both multi-temporal and post-event datasets, thus indicating the universal character of this property of landslides and suggesting that the same mechanisms drive the dynamics of mass wasting processes. The reasons for the scaling behavior of landslide sizes are widely debated, since their understanding would improve our knowledge of the spatial and temporal evolution of this phenomenon. Self-Organized Critical (SOC) dynamics and the key role of topography have been suggested as possible explanations. The scaling exponent of the landslide size-frequency distribution defines the probability of landslide magnitudes and it thus represents an important parameter for hazard assessment. Therefore, another - still unanswered - important question concerns the factors on which its value depends. This paper investigates these issues using a Cellular Automata (CA) model. The CA uses a real topographic surface acquired from a Digital Elevation Model to represent the initial state of the system, where the states of cells are defined in terms of altitude. The stability criterion is based on the slope gradient. The system is driven to instability through a temporal decrease of the stability condition of cells, which may be thought of as representing the temporal weakening of soil caused by factors like rainfall. A transition rule defines the way in which instabilities lead to discharge from unstable cells to the neighboring cells, deciding upon the landslide direction and the quantity of mass involved. Both the direction and the transferred mass depend on the local topographic features. The scaling properties of the area-frequency distributions of the resulting landslide series are investigated for several rates of weakening and for different time windows, in order to explore the response of the system to model
Results evaluation of max rule, min rule and product rule in score fusion multibiometric systems
Shekhar Karanwal,
2010-07-01
Full Text Available this paper discusses about unibiometric systems, multibiometric systems, product rule, max rule and min rule of score level fusion. Score level fusion is used to generate scores of a person. Min max normalization scheme is used for normalization which normalizes scoresbetween 0 and 1. The proposed method also evaluates the results between product rule, min rule and max rule.
Eisenhardt, K M; Sull, D N
2001-01-01
The success of Yahoo!, eBay, Enron, and other companies that have become adept at morphing to meet the demands of changing markets can't be explained using traditional thinking about competitive strategy. These companies have succeeded by pursuing constantly evolving strategies in market spaces that were considered unattractive according to traditional measures. In this article--the third in an HBR series by Kathleen Eisenhardt and Donald Sull on strategy in the new economy--the authors ask, what are the sources of competitive advantage in high-velocity markets? The secret, they say, is strategy as simple rules. The companies know that the greatest opportunities for competitive advantage lie in market confusion, but they recognize the need for a few crucial strategic processes and a few simple rules. In traditional strategy, advantage comes from exploiting resources or stable market positions. In strategy as simple rules, advantage comes from successfully seizing fleeting opportunities. Key strategic processes, such as product innovation, partnering, or spinout creation, place the company where the flow of opportunities is greatest. Simple rules then provide the guidelines within which managers can pursue such opportunities. Simple rules, which grow out of experience, fall into five broad categories: how- to rules, boundary conditions, priority rules, timing rules, and exit rules. Companies with simple-rules strategies must follow the rules religiously and avoid the temptation to change them too frequently. A consistent strategy helps managers sort through opportunities and gain short-term advantage by exploiting the attractive ones. In stable markets, managers rely on complicated strategies built on detailed predictions of the future. But when business is complicated, strategy should be simple. PMID:11189455
Genetic Dominance & Cellular Processes
Seager, Robert D.
2014-01-01
In learning genetics, many students misunderstand and misinterpret what "dominance" means. Understanding is easier if students realize that dominance is not a mechanism, but rather a consequence of underlying cellular processes. For example, metabolic pathways are often little affected by changes in enzyme concentration. This means that…
Radioactivity of cellular concrete
The natural radioactivity of cellular concrete is discussed. Some data on the concentrations of 40K, 226Ra and 232Th in building materials in Poland are given. The results of dose rates measurements in living quarters as well as outside are presented. (A.S.)
Claman, Henry N.
1973-01-01
Discusses the nature of the immune response and traces many of the discoveries that have led to the present state of knowledge in immunology. The new cellular immunology is directing its efforts toward improving health by proper manipulation of the immune mechanisms of the body. (JR)