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The modern molecular clock.

by Lindell Bromham , David Penny - Nat Rev Genet , 2003
"... has clear implications for our understanding of the tempo and mode of important transitions in evolution. But the controversy over the molecular clock is not just the concern of evolutionary theorists: the practical benefits of the molecular clock are immense. For example, molecular clock dates tha ..."
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has clear implications for our understanding of the tempo and mode of important transitions in evolution. But the controversy over the molecular clock is not just the concern of evolutionary theorists: the practical benefits of the molecular clock are immense. For example, molecular clock dates

CELL CLOCKS Clock Genes in Cell Clocks: Roles, Actions, and Mysteries

by Hitoshi Okamura
"... Abstract Cellular events must be organized in the time dimension as well as in the space dimension for many proteins to perform their cellular functions effec-tively. The intracellular molecular oscillating loops that compose the cell’s circa-dian clock coordinate the timing of the expression of a v ..."
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Abstract Cellular events must be organized in the time dimension as well as in the space dimension for many proteins to perform their cellular functions effec-tively. The intracellular molecular oscillating loops that compose the cell’s circa-dian clock coordinate the timing of the expression of a

The moral problem

by Michael R. Smith, Weatherdata Incorporated , 1994
"... Even with the considerable progress in atmospheric science during the twentieth century, there remains considerable room for improvement in the accuracy of the public warnings of tornadoes, flash floods, large hail and damaging thunderstorm winds. But even if we had perfect knowledge of the process ..."
Abstract - Cited by 204 (9 self) - Add to MetaCart
of tornadogenesis, for example, inadequate atmospheric sampling and measurements would still prevent warning accuracy from ever reaching 100 percent. Stewart (2000) states the problem succinctly: Every prediction contains an element of irreducible uncertainty … actions that are based on predictions lead to two

Active Database Systems

by Norman Paton, Oscar Diaz , 1999
"... , Exception, Clock, Externalg Granularity ae fMember, Subset, Setg Type ae fPrimitive, Composite g Operators ae for, and, seq, closure, times, not g Consumption mode ae fRecent, Chronicle, Cumulative, Continuous g Role 2 fMandatory, Optional, Noneg Condition Role 2 fMandatory, Optional, Noneg Contex ..."
Abstract - Cited by 198 (3 self) - Add to MetaCart
, Exception, Clock, Externalg Granularity ae fMember, Subset, Setg Type ae fPrimitive, Composite g Operators ae for, and, seq, closure, times, not g Consumption mode ae fRecent, Chronicle, Cumulative, Continuous g Role 2 fMandatory, Optional, Noneg Condition Role 2 fMandatory, Optional, Noneg

THE REPLICATION CLOCK

by Ltamar Simon, Howard Cedar
"... In every organism, DNA replication takes place in an ordered physical and temporal fashion. Although this process is primarily necessary to carry out the task of copying the genome, it may also indirectly play a role in the regulation of gene expression. In Escherichiu coli, for exam-ple, the entire ..."
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synthesis is accomplished through the action of multiple bidirectional origins. If all of these replica-tion units were activated simultaneously, the entire process of replication could be completed very quickly. However, replication starts are actually distributed in a programmed manner throughout

CONTROLLER SYNTHESIS FOR TIMED AUTOMATA

by Eugene Asarin, Oded Maler, Amir Pnueli, Joseph Sifakis
"... In this work we tackle the following problem: given a timed automaton, restrict its transition relation in a systematic way so that all the remaining behaviors satisfy certain properties. This is an extension of the problem of controller synthesis for discrete event dynamical systems, where in addi ..."
Abstract - Cited by 157 (14 self) - Add to MetaCart
in addition to choosing among actions, the controller have the option of doing nothing and let the time pass. The problem is formulated using the notion of a real-time game, and a winning strategy is constructed as a fixed-point of an operator on the space of states and clock configurations.

Integrating System Descriptions by Clocked Guarded Actions

by Jens Brandt, Mike Gemünde, Klaus Schneider, Sandeep K. Shukla, Jean-pierre Talpin
"... For the description of reactive systems, there is a large number of languages and formalisms, and depending on a particular application or design phase, one of them may be better suited than another one. In the design of reactive systems, their integration is a key issue for a system-wide simulation ..."
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-wide simulation, analysis and verification. In this paper, we propose clocked guarded actions as a unified intermediate representation for several synchronous and asynchronous models in the design flow, which does not only provide an integrated description but it also allows designers to share common components

Integrating System Descriptions by Clocked Guarded Actions

by unknown authors
"... Abstract—For the description of reactive systems, there is a large number of languages and formalisms, and depending on a particular application or design phase, one of them may be better suited than another one. In the design of reactive systems, their integration is a key issue for a system-wide s ..."
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-wide simulation, analysis and verification. In this paper, we propose clocked guarded actions as a unified intermediate representation for several synchronous and asynchronous models in the design flow, which does not only provide an integrated description but it also allows de-signers to share common components

Mobile Processes With Local Clocks

by Pierpaolo Degano, Jean-vincent Loddo, Corrado Priami - In Proceedings of Workshop on Analysis and Verification of Multiple-Agent Languages, LNCS 1192 , 1996
"... . We propose a structural operational semantics that expresses temporal aspects of mobile and distributed systems, each sequential component of which has its local clock. Since the run-time support of a programming language implements the operations of the language via some lower-level routines, the ..."
Abstract - Cited by 9 (2 self) - Add to MetaCart
. We propose a structural operational semantics that expresses temporal aspects of mobile and distributed systems, each sequential component of which has its local clock. Since the run-time support of a programming language implements the operations of the language via some lower-level routines

GRAVITY, GAUGES AND CLOCKS

by Pierre Teyssandier, Robin W Tucker , 1995
"... We discuss the definitions of standard clocks in theories of gravitation. These definitions are motivated by the invariance of actions under different gauge symmetries. We contrast the definition of a standard Weyl clock with that of a clock in general relativity and argue that the historical critic ..."
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We discuss the definitions of standard clocks in theories of gravitation. These definitions are motivated by the invariance of actions under different gauge symmetries. We contrast the definition of a standard Weyl clock with that of a clock in general relativity and argue that the historical
Results 1 - 10 of 406