¸´ÔÓÐÔÎÄÕª NO£º2003.30
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Complexity Digest 2003.30 Archive: http://www.comdig.org,
European Mirror:
http://www.comdig.de
Asian Mirror: http://www.phil.pku.edu.cn/resguide/comdig/
(Chinese GB-Code)
"I think the next
century will be the century of complexity." Stephen Hawking
_________________________________________________________________
Content:
01. Information Technology And Economic Performance: Review Of The
Empirical Evidence , ACM
Computing Surveys
02. Tapping the Mood Gene , NYTimes
02.01. Getting the Short End of the Allele , Science
02.02. Influence of Life Stress on Depression , Science
03. Supercomputing: Simulators Face Real Problems , Science
04. Development as a Dynamic System , Trends in Cognitive Sciences
04.01. The Segmentation Clock: Converting Embryonic Time into Spatial
Pattern , Science
04.02. Time for Chronomics? , Science
04.03. To Every Thing There Is a Season , Science
05. Evolutionary Biology: Body Plans And Simple Brains , Nature
06. Ecology: Evolution In Population Dynamics , Nature
06.01. Ecology: Birds Sing At A Higher Pitch In Urban Noise , Nature
07. Mutation Landscapes , Journal of Theoretical Biology
07.01. Larger than Life: threshold-range scaling of Life's coherent
structures , Physica D:
Nonlinear Phenomena
08. Reproductive Isolation Driven By Effects Of Ecological Adaptation And
Reinforcement ,
Alphagalileo & Proc. B
08.01. Quantifying Male Attractiveness , Alphagalileo & Proc. B
09. Viral Self-Assembly As A Thermodynamic Process , Phys. Rev. Lett.
10. Memory in Retroviral Quasispecies: Experimental Evidence and
Theoretical Model for Human
Immunodeficiency Virus , Journal of Molecular Biology
11. Managing Models Of Signaling Networks , Neurocomputing
12. Electronic Neuron Within A Ganglion Of A Leech , Phys. Rev. E
13. Neuroscience: A New Of The Brain , Nature
14. Brain Machine 'Improves Musicianship' , BBC News
15. When Is a Word Not a Word? , Science
15.01. Lateralized Cognitive Processes and Lateralized Task Control , Science
16. Flicker Flutter: Is an Illusory Event as Good as the Real Thing? ,
Journal of Vision
16.01. Sustained Division Of The Attentional Spotlight , Nature
17. "Cellular Automaton Model for the Simulation of Laser Dynamics" ,
Physical Review E
18. Your Permanent Record , Wired
18.01. Pentagon Alters LifeLog Project , Wired News
19. Complex Challenges: Global Terrorist Networks
19.01. Planned U.S. Sensor Network Targets Terror Threats , EE Times
19.02. Before and After Sept. 11 , NYTimes
19.03. Classified Section of Sept. 11 Report Faults Saudi Rulers , NYTimes
19.03.01. Full Text: Congressional Report on 9/11 , NYTimes
19.04. Faith-Based Intelligence , The New Yorker
19.05. Intelligence Quagmire: How To Gauge The New IQ , The Christian
Science Monitor
20. Links & Snippets
20.01. Other Papers
20.02. Webcast Announcements
20.03. Conference & Call for Papers Announcements
20.04. ComDig Announcement: New ComDig Archive in Beta Test
_________________________________________________________________
01. Information Technology And Economic Performance: Review Of The
Empirical Evidence , ACM
Computing Surveys
Abstract: (...) there has been considerable debate about whether the IT
revolution was paying off
in higher productivity. Studies in the 1980s found no connection between IT
investment and
productivity in the U.S. economy, a situation referred to as the
productivity paradox. Since then,
a decade of studies at the firm and country level has consistently shown
that the impact of IT
investment on labor productivity and economic growth is significant and
positive. This article
critically reviews the published research, more than 50 articles, on
computers and productivity.
The review concludes that the productivity paradox as first formulated has
been effectively
refuted.
* Information Technology And Economic Performance: A Critical Review Of The
Empirical Evidence, J.
Dedrick, V. Gurbaxani & K. L. Kraemer, Mar. 2003, DOI: 10.1145/641865.641866
* Contributed by Pritha Das
_________________________________________________________________
02. Tapping the Mood Gene , NYTimes
Excerpts: (? effects of stressful events in early adulthood and the way
that responses to them are
mediated by a single gene, called 5-HTT. (? The gene makes a protein that
modifies nerve cells'
use of serotonin, a chemical messenger important in the regulation of mood.
The short version of
the gene was linked (if weakly) to neuroticism, as a personality trait; the
news media called 5-HTT
the "Woody Allen gene."
The long variant of the gene seems to confer emotional resilience.
* Tapping the Mood Gene, Peter D. Kramer, 3/07/26, NYTimes
_________________________________________________________________
02.01. Getting the Short End of the Allele , Science
Excerpts: For people with two s alleles (17% of the group), the probability
of a major depressive
episode rose to 43% among those who had been through four or more stressful
experiences. That was
more than double the risk for the subjects with two l's (who made up 31% of
the group) who had been
similarly buffeted by life's vicissitudes. The average score on a
depression symptom inventory was
likewise more than twice as high for stressed people with two s alleles as
for those with two l
versions.
* Getting the Short End of the Allele, Constance Holden, Jul 18 2003,
Science: 291-293
_________________________________________________________________
02.02. Influence of Life Stress on Depression , Science
Excerpts: In a prospective-longitudinal study of a representative birth
cohort, we tested why
stressful experiences lead to depression in some people but not in others.
(...) Individuals with
one or two copies of the short allele of the 5-HT T promoter polymorphism
exhibited more depressive
symptoms, diagnosable depression, and suicidality in relation to stressful
life events than
individuals homozygous for the long allele. This epidemiological study thus
provides evidence of a
gene-by-environment interaction, in which an individual's response to
environmental insults is
moderated by his or her genetic makeup.
* Influence of Life Stress on Depression: Moderation by a Polymorphism in
the 5-HTT Gene, Avshalom
Caspi, Karen Sugden, Terrie E. Moffitt, Alan Taylor, Ian W. Craig, HonaLee
Harrington, Joseph
McClay, Jonathan Mill, Judy Martin, Antony Braithwaite, Richie Poulton, Jul
18 2003, Science :
386-389
_________________________________________________________________
03. Supercomputing: Simulators Face Real Problems , Science
Excerpts: One problem plaguing U.S. machines is efficiency--the amount of
work actually performed
compared with the amount of work that would get done if each processor
could work continuously
without needing to wait for data to arrive. For climate problems, the Earth
Simulator operates at
30% efficiency or higher, well above what U.S. machines can achieve.
"Inadequate bandwidth and
network latency limit us to about 1% of the peak performance (...). "That's
typical of the
[off-the-shelf component-based] architectures that we've grown so fond of
in the United States.
* Supercomputing: Simulators Face Real Problems, Katie Greene, Jul 18 2003,
Science, 301-302
_________________________________________________________________
04. Development as a Dynamic System , Trends in Cognitive Sciences
Abstract: Development is about creating something more from something less,
for example, a walking
and talking toddler from a helpless infant. One current theoretical
framework views the
developmental process as a change within a complex dynamic system.
Development is seen as the
emergent product of many decentralized and local interactions that occur in
real time. We examine
how studying the multicausality of real-time processes could be the key to
understanding change
over developmental time. We specifically consider recent research and
theory on perseverative
reaching by infants as a case study that demonstrates this approach.
* Development as a Dynamic System, Linda B. Smith, Esther Thelen,
2003-07-15, DOI:
10.1016/S1364-6613(03)00156-6, Trends in Cognitive Sciences Article in
Press, Corrected Proof
* Contributed by Carlos Gershenson
_________________________________________________________________
04.01. The Segmentation Clock: Converting Embryonic Time into Spatial
Pattern , Science
Excerpts: In most animal species, the anteroposterior body axis is
generated by the formation of
repeated structures called segments. In vertebrate segmentation, a
specialized mesodermal structure
called the somite gives rise to skeletal muscles, vertebrae, and some
dermis. Formation of the
somites is a rhythmic process that involves an oscillator -the segmentation
clock- (...). This
process converts the temporal oscillations into the periodic spatial
pattern of somite boundaries.
The study of somite development provides insights into the spatiotemporal
integration of signaling
systems in the vertebrate embryo.
* The Segmentation Clock: Converting Embryonic Time into Spatial Pattern,
Olivier Pourquie, Jul 18
2003, Science, 328-330
_________________________________________________________________
04.02. Time for Chronomics? , Science
Excerpts: Ever since the derivation of the theory of relativity, physicists
have done reasonably
well in understanding time; however, biologists are still waiting for a
comprehensive theory of
timing in living systems: a corpus of "laws" describing how cells and
organisms can precisely
initiate and terminate processes at specified times. This deficiency is
particularly acute in
developmental biology, where complex mechanisms of various paces and
durations must be orchestrated
to solve huge developmental problems such as the one faced by the
fertilized egg: how to become an
organism.
* Time for Chronomics?, Denis Duboule, Science 2003 301: 277
_________________________________________________________________
04.03. To Every Thing There Is a Season , Science
Excerpts: From cells to whole organisms, there is a time to grow and a time
to proliferate; a time
to keep silent and a time to express; a time to change and a time to
refrain from transformation.
But where are the cellular and organismal timepieces and how do they mark
off time and keep the
myriad physiological events in sync? (...) The clustered Hox genes are
activated in a temporal and
spatial manner that corresponds to their order on the chromosomes.
* To Every Thing There Is a Season, Beverly Purnell, Science 2003 301: 325
_________________________________________________________________
05. Evolutionary Biology: Body Plans And Simple Brains , Nature
Excerpts: Genes expressed in the vertebrate brain and spinal cord show up
in the surface nerve net
of a closely related group of invertebrates. Could this mean that brains
started out on the body
surface?
* Evolutionary Biology: Body Plans And Simple Brains, Thurston Lacalli, 17
July 2003, DOI:
10.1038/424263a, Nature 424, 263 - 264
_________________________________________________________________
06. Ecology: Evolution In Population Dynamics , Nature
Excerpts: Ecologists studying population dynamics prefer not to bother with
the possibility of
evolutionary change affecting their study organisms. This is sensible,
because understanding the
results of interactions between, for example, populations of predators and
prey is already a
complicated task. Making the assumption that evolutionary processes are too
slow on ecological
scales greatly eases the task of modelling the commonly observed population
oscillations. But an
elegant study by Yoshida et al.1 (page 303 of this issue) decisively
demonstrates that this
simplification might no longer be tenable.
* Ecology: Evolution In Population Dynamics, Peter Turchin, DOI:
10.1038/424257a, Nature 424, 257 -
258
_________________________________________________________________
06.01. Ecology: Birds Sing At A Higher Pitch In Urban Noise , Nature
Excerpts: Great tits hit the high notes to ensure that their mating calls
are heard above the
city's din.
Great tits hit the high notes to ensure that their mating calls are heard
(...).
The ongoing spread of urban areas, highways and airports throughout the
world makes anthropogenic
noise almost omnipresent. We have found that urban great tits (Parus major)
at noisy locations sing
with a higher minimum frequency, thereby preventing their songs from being
masked to some extent by
the predominantly low-frequency noise. They have presumably learned
selectively from a restricted
range of their repertoire - a behavioural plasticity that may be critical
for breeding success in a
noisy world.
* Ecology: Birds Sing At A Higher Pitch In Urban Noise, Hans Slabbekoorn,
Margriet Peet, 17 July
2003, DOI: 10.1038/424267a, Nature 424, 267
_________________________________________________________________
07. Mutation Landscapes , Journal of Theoretical Biology
Abstract: A traditional picture of evolutionary dynamics with constant
fitness is that of genomes
living in sequence space and adapting on fitness landscapes. Mutation rates
are considered to be
constant or externally regulated. If, however, we take into account that
genomes also encode for
enzymes that perform replication and error correction, then individual
genomes not only have a
specific replication rate (fitness), but also a specific mutation rate.
This leads to the concept
of a mutation landscape. We explore evolution on mutation landscapes.
Localization in pure mutation
landscapes is only possible under extremely restrictive conditions.
Coupling of mutation landscapes
and fitness landscapes leads to localization and hence adaptation and
evolution. We analyse how
mutation landscapes facilitate localization in fitness landscapes and vice
versa. Finally, we show
that for mutation landscapes, at equilibrium, with constant environment,
there is not necessarily
selection for the minimum mutation rate. Instead, the target of selection
is an optimum
distribution of mutation rates, a `mutational quasispecies'.
* Mutation Landscapes, Akira Sasaki, Martin A. Nowak, 2003-07-16, DOI:
10.1016/S0022-5193(03)00161-9, Journal of Theoretical Biology Article in
Press, Corrected Proof
* Contributed by Carlos Gershenson
_________________________________________________________________
07.01. Larger than Life: threshold-range scaling of Life's coherent
structures , Physica D:
Nonlinear Phenomena
Abstract: The Game of Life has many coherent structures known as still
lifes, oscillators, and
spaceships. The most intriguing of these structures are the spaceships due
to their ability to
carry information across long spatial distances. Similar structures are
supported by Larger than
Life (LtL), which is a four-parameter family of two-dimensional cellular
automata that generalizes
the Game of Life to large neighborhoods and general birth and survival
thresholds. Numerous
examples of large range versions of Life's spaceships are provided along
with descriptions of the
experimental methods used to find these objects. The empirical work
illustrates that these
structures are quite common, scale in a fairly coherent manner, and have a
distinct geometry. A mix
of rigorous results, questions, and conjectures are made about the
existence of the generalized
spaceships and other coherent structures for LtL rules with arbitrarily
large neighborhoods as well
as the convergence of such rules to "Euclidean automata". Euclidean
automata are deterministic
rules that have Euclidean, rather than discrete universes.
* Larger than Life: threshold-range scaling of Life's coherent structures,
Kellie Michele Evans,
2003-07-19, DOI: 10.1016/S0167-2789(03)00155-6, Physica D: Nonlinear
Phenomena Article in Press,
Corrected Proof
* Contributed by Carlos Gershenson
_________________________________________________________________
08. Reproductive Isolation Driven By Effects Of Ecological Adaptation And
Reinforcement ,
Alphagalileo & Proc. B
Abstract: How new species originate has been one of the most important
questions in evolutionary
biology since Darwin. We studied the processes involved in species
formation using walking-stick
insect populations that live on two different species of plants. Females
that mate with males from
the other plant species produce offspring that are less camouflaged than
females that mate with
males from their own plant species. We show that natural selection has thus
favoured females who
discriminate (...). These findings show how natural selection can favour
the evolution of
more-selective mate choice, which can lead to greater progress towards
formation of new species.
* Reproductive Isolation Driven By The Combined Effects Of Ecological
Adaptation And Reinforcement,
P. Nosil, B. J. Crespi & C. P. Sandoval, 2003/07/21
* Contributed by Atin Das
_________________________________________________________________
08.01. Quantifying Male Attractiveness , Alphagalileo & Proc. B
Abstract: Ronald Fisher suggested that female choosiness for certain male
traits could be
maintained in a population because females that are choosy produce sons
that inherit their father's
trait and so are chosen by females. Formal genetic models have previously
shown that this seemingly
circular argument is sound. In this paper we show how genetic arguments can
be reformulated in
terms of an appropriate measure of male attractiveness. Results demonstrate
that selection can
maintain female preference for a culturally inherited male trait, even when
the preference leads to
fewer (but more attractive) offspring being produced.
* Quantifying Male Attractiveness, J. M. McNamara, A. I. Houston, M. dos
Santos, H. Kokko & R.
Brooks, 2003/07/21
* Contributed by Atin Das
_________________________________________________________________
09. Viral Self-Assembly As A Thermodynamic Process , Phys. Rev. Lett.
Abstract: The protein shells, or capsids, of nearly all spherelike viruses
adopt icosahedral
symmetry. In the present Letter, we propose a statistical thermodynamic
model for viral
self-assembly. We find that icosahedral symmetry is not expected for viral
capsids constructed from
structurally identical protein subunits and that this symmetry requires (at
least) two internal
"switching" configurations of the protein. Our results indicate that
icosahedral symmetry is not a
generic consequence of free energy minimization but requires optimization
of internal structural
parameters of the capsid proteins.
* Viral Self-Assembly As A Thermodynamic Process, R. F. Bruinsma, W. M.
Gelbart, D. Reguera, J.
Rudnick & R. Zandi, 2003/06/20, DOI: 10.1103/PhysRevLett.90.248101
* Contributed by Atin Das
_________________________________________________________________
10. Memory in Retroviral Quasispecies: Experimental Evidence and
Theoretical Model for Human
Immunodeficiency Virus , Journal of Molecular Biology
Abstract: Viral quasispecies may possess a molecular memory of their past
evolutionary history,
imprinted on minority components of the mutant spectrum. Here we report
experimental evidence and a
theoretical model for memory in retroviral quasispecies in vivo. Apart from
replicative memory
associated with quasispecies dynamics, retroviruses may harbour a
"cellular" or "anatomical" memory
derived from their integrative cycle and the presence of viral reservoirs
in body compartments.
Three independent sets of data exemplify the two kinds of memory in human
immunodeficiency virus
type 1 (HIV-1). The data provide evidence of re-emergence of sequences that
were hidden in cellular
or anatomical compartments for extended periods of infection, and recovery
of a quasispecies from
pre-existing genomes. We develop a three-component model that incorporates
the essential features
of the quasispecies dynamics of retroviruses exposed to selective
pressures. Significantly, a
numerical study based on this model is in agreement with the experimental
data, further supporting
the existence of both replicative and reservoir memory in retroviral
quasispecies.
* Memory in Retroviral Quasispecies: Experimental Evidence and Theoretical
Model for Human
Immunodeficiency Virus, Carlos Briones, Esteban Domingo, Carmen
Molina-Par¨ªs, 2003-08-1, DOI:
10.1016/S0022-2836(03)00661-2, Journal of Molecular Biology 331(1):213-229
* Contributed by Carlos Gershenson
_________________________________________________________________
11. Managing Models Of Signaling Networks , Neurocomputing
Abstract: Signaling pathways participate in complex information processing
networks. These networks
handle housekeeping functions of the cell as well as specialized functions
such as synaptic
plasticity. I report two developments in managing such networks: a
compilation of mass-action
kinetic models of signaling pathways, and shared motifs in the chemistry of
interactions between
signaling pathways. These motifs may prove useful in abstracting signaling
networks, without
compromising chemical reaction details. The combination of a library of
signaling pathway models,
and high-level rules to connect these pathways, may simplify development of
complex signaling
network models.
* Managing Models Of Signaling Networks, U. S. Bhalla , Jun. 2003, DOI:
10.1016/S0925-2312(02)00737-3
* Contributed by Pritha Das
_________________________________________________________________
12. Electronic Neuron Within A Ganglion Of A Leech , Phys. Rev. E
Abstract: We report the construction of an electronic device that models
and replaces a neuron in a
midbody ganglion of the leech Hirudo medicinalis. In order to test the
behavior of our device, we
used a well-characterized synaptic interaction between the mechanosensory,
sensitive to pressure,
(P) cell and the anteropagoda (because of the action potential shape) (AP)
neuron. We alternatively
stimulated a P neuron and our device connected to the AP neuron, and
studied the response of the
latter. The number and timing of the AP spikes were the same when the
electronic parameters were
properly adjusted.
* Electronic Neuron Within A Ganglion Of A Leech (Hirudo Medicinalis), J.
Aliaga, N. Busca, V.
Minces, G. B. Mindlin, B. Pando, A. Salles & L. Sczcupak, 2003/06/27, DOI:
10.1103/PhysRevE.67.066118
* Contributed by Atin Das
_________________________________________________________________
13. Neuroscience: A New Of The Brain , Nature
Excerpts: When considering the location of human cognitive functions,
neuroscientists still refer
to imprecise anatomical maps drawn up almost a century ago. (...) By
entrusting the analysis to
computers, Zilles has removed human bias from the business of defining
borders between brain
regions. (...) The final product will involve 15 brains to generate a
'probabilistic map', against
which any point selected from, say, an MRI image of a living brain can be
said to lie within a
particular structure with a certain probability.
* Neuroscience: A New Of The Brain, Alison Abbott, 17 July 2003, DOI:
10.1038/424249a, Nature 424,
249 - 250
_________________________________________________________________
14. Brain Machine 'Improves Musicianship' , BBC News
Excerpts: Students were assessed on two pieces of music before and after
neurofeedback sessions.
(...) These filtered brainwaves are then 'fed back' to the individual in
the form of a video game
displayed on a screen. The participant learns to control the game by
altering particular aspects of
their brain activity. This alteration in brain activity can influence
performance. A panel of
expert judges found the 97 Royal College of Music students improved in a
number of areas, including
musical understanding, imagination, and communication with the audience.
* Brain Machine 'Improves Musicianship', 03/07/24, BBC News
_________________________________________________________________
15. When Is a Word Not a Word? , Science
Excerpts: One difficulty in assessing the differential specialization of
the two hemispheres is
choosing the most appropriate stimulus. Thus, when assessing visuospatial
judgment tasks, the
tendency is to avoid a linguistic stimulus. (...) if lateralization depends
on the task rather than
the stimulus, then the same stimulus could be used to directly test
lateralization of linguistic
and visuospatial functions. Short words, with one letter colored red, were
presented (...)judged
whether the word contained the letter "A," ignoring the red letter.
(...)
indicating whether the
red letter was right or left of center.
* When Is a Word Not a Word?, Anthony R. McIntosh, Nancy J. Lobaugh, Jul 18
2003, Science, 322-323
_________________________________________________________________
15.01. Lateralized Cognitive Processes and Lateralized Task Control , Science
Excerpts: The principles underlying human hemispheric specialization are
poorly understood. We used
functional magnetic resonance imaging of letter and visuospatial decision
tasks with identical word
stimuli to address two unresolved problems. First, hemispheric
specialization depended on the
nature of the task rather than on the nature of the stimulus. Second,
analysis of frontal candidate
regions for cognitive control showed increased coupling between left
(...)(ACC) (...) during letter
decisions, whereas right ACC showed enhanced coupling with right parietal
areas during visuospatial
decisions. Cognitive control is thus localized in the same hemisphere as
task execution.
* Lateralized Cognitive Processes and Lateralized Task Control, Klaas E.
Stephan, John C. Marshall,
Karl J. Friston, James B. Rowe, Afra Ritzl, Karl Zilles, Gereon R. Fink,
Jul 18 2003, Science,
384-386
_________________________________________________________________
16. Flicker Flutter: Is an Illusory Event as Good as the Real Thing? ,
Journal of Vision
Abstract: Verghese and Stone (1995) showed that reducing the perceived
number of objects by
grouping also reduces objective performance. Shams, Kamitani, and Shimojo
(2000) showed that a
single flash accompanied by multiple beeps appears to flash more than once.
We show that objective
orientation-discrimination performance depends solely on the perceived
number of flashes,
independent of the actual number of beeps and flashes. Thus the unit of
perceptual analysis seems
to be a perceived event, independent of how it is induced.
* Flicker Flutter: Is an Illusory Event as Good as the Real Thing?, Tracey
D. Berger, Marialuisa
Martelli, Denis G. Pelli, 2003-07-17, DOI: 10:1167/3.6.1, Journal of Vision
3(6){1}:406-412
See also ComDig 03-29: An Irrelevant Light Enhances Auditory Detection in
Humans: A Psychophysical
Analysis Of Multisensory Integration In Stimulus Detection, Christopher T.
Lovelace, Barry E. Stein
, Mark T. Wallace, 2003-07-15, DOI: 10.1016/S0926-6410(03)00160-5,
Cognitive Brain Research
17(2):447-453
* Contributed by Carlos Gershenson
_________________________________________________________________
16.01. Sustained Division Of The Attentional Spotlight , Nature
Excerpts: By voluntarily directing attention to a specific region of a
visual scene, we can improve
our perception of stimuli at that location1. This ability to focus
attention upon specific zones of
the visual field has been described metaphorically as a moveable spotlight
or zoom lens that
facilitates the processing of stimuli within its 'beam'2, 3.
[Here we] (...) show that the spotlight may be divided between spatially
separated locations
(excluding interposed locations) over more extended time periods. This
spotlight division appears
to be accomplished at an early stage of visual-cortical processing.
* Sustained Division Of The Attentional Spotlight, M. M. Muller, P.
Malinowski, T. Gruber, S. A.
Hillyard, 17 July 2003, DOI: 10.1038/nature01812, Nature 424, 309 - 312
_________________________________________________________________
17. "Cellular Automaton Model for the Simulation of Laser Dynamics" ,
Physical Review E
Excerpts: In a laser system, the interactions among simple atoms and the
radiation they produce can
give rise to cooperative phenomena. However, the usual approach for its
study is based on very
detailed microscopical equations, which somehow mask the action of such
cooperative properties. In
this study, a simple cellular automaton model is presented, which
reproduces much of the laser
phenomenology, special attention being focused on these self-organizing
cooperative effects. Our
model is interesting in that it illustrates the emergence of laser
properties as cooperative
phenomena based on simple underlying rules. It can also be useful in
calculating laser output in
situations which are difficult to treat with the traditional approach based
on the resolution of
detailed differential equations. One example is when dealing with complex
boundary conditions or
numerical difficulties in the integration of the equations.
* "Cellular Automaton Model for the Simulation of Laser Dynamics",
J.L.
Guisado, F.
Jim¨¦nez-Morales, J.M. Guerra, DOI: 10.1103/PhysRevE.67.066708, Physical
Review E Contrib by: Jose
Luis Guisado Lizar
_________________________________________________________________
18. Your Permanent Record , Wired
Excerpts: In a fully realized digital memory management system, your camera
will come with a
self-setting clock, a built-in GPS locator, and perhaps 100 gigs of flash
memory. Every picture or
video snippet that you shoot will be embedded with date and location
information. Your standard OS
will include sophisticated face-matching software. Your computer will be
your shoe box -(...). And
ferreting out every picture of Granny at your daughter's graduation will
become a matter of simply
setting a few parameters in Photo Find and pressing Return.
* Your Permanent Record, CTO David Vaskevitch, 03/08, Wired, 11.08
_________________________________________________________________
18.01. Pentagon Alters LifeLog Project , Wired News
Excerpts: Lifelog http://www.darpa.mil/ipto/research/llog/index.html
is the
Defense Advanced
Research Projects Agency's effort to gather every conceivable element of a
person's life, (...).
It's an attempt, some say, to make a kind of surrogate, digitized memory.
(...) (...) Darpa changed
http://www.darpa.mil/ipto/Solicitations/Mod3_03-30.html
the LifeLog
proposal request. Now: "LifeLog
researchers shall not capture imagery or audio of any person without that
person's a priori express
permission. In fact, it is desired that capture of imagery or audio of any
person other than the
user be avoided even if a priori permission is granted."
* Pentagon Alters LifeLog Project, Noah Shachtman, 03/07/14, Wired News
_________________________________________________________________
19. Complex Challenges: Global Terrorist Networks
_________________________________________________________________
19.01. Planned U.S. Sensor Network Targets Terror Threats , EE Times
Excerpts: In one approach, researchers are studying hybrid sensors that use
surface-chemical
detection as a first step, or trigger, that could be followed up with more
expensive and
time-consuming techniques (...) The goal for all the government efforts,
perhaps three to five
years out, is to deploy a highly accurate yet low-cost network of sensors
"that in a couple of
minutes could tell you if an agent is present, in what concentration and
something about the agent.
But the technology for that doesn't really exist yet,"(...)
* Planned U.S. Sensor Network Targets Terror Threats, Rick Merritt,
03/07/14, EE Times
_________________________________________________________________
19.02. Before and After Sept. 11 , NYTimes
Excerpts: It would be nice to believe that all the problems had been fixed.
(...) The next
examination of the government's conduct prior to Sept. 11 will come from
the commission headed by
Thomas Kean, the former governor of New Jersey. The administration must
give the commission the
information it has requested on relevant White House and National Security
Council discussions. The
White House's refusal to give Congress unfettered access to information
about Saudi Arabia's links
to terrorism was a mistake that should not be repeated with the Kean panel.
* Before and After Sept. 11, 03/07/25, NYTimes
_________________________________________________________________
19.03. Classified Section of Sept. 11 Report Faults Saudi Rulers , NYTimes
Excerpts: Some people who have read the classified chapter said it
represented a searing indictment
of how Saudi Arabia's ruling elite have,(...), distributed millions of
dollars to terrorists (...).
Mr. Bayoumi helped pay the expenses for the men, Khalid Almidhar and Nawaq
Alhazmi. Mr. Bayoumi,
the report said, "had access to seemingly unlimited funding from Saudi
Arabia." The report said Mr.
Bayoumi was employed by the Saudi civil aviation authority and left open
his motivations for
supporting the two men.
* Classified Section of Sept. 11 Report Faults Saudi Rulers, David
Johnston, 03/07/26, NYTimes
_________________________________________________________________
19.03.01. Full Text: Congressional Report on 9/11 , NYTimes
* Full Text: Congressional Report on 9/11, NYTimes
_________________________________________________________________
19.04. Faith-Based Intelligence , The New Yorker
Excerpts: "The British government has learned that Saddam Hussein recently
sought significant
quantities of uranium from Africa." So said President Bush on January 28th,
outlining the case for
war with Iraq in his State of the Union address. (...) most chilling moment
of the speech, for it
raised the spectre of nuclear weapons in the hands of a dictator who had
proved himself capable of
terror, invasion, and genocide. To many listeners, the attribution of this
sensational piece of
information to the British served only to emphasize its reliability.
Editor's Note: George Orwell's "Animal Farm" illustrates a generic
phenomenon of complex social
systems: that valuable ideas (such as "All Animals are Created Equal")
will
eventually be eroded
and abused by power-hungry individuals, unless a reliable system of checks
and balances prevent
that from happening. Today we observe that an idea ("prevent terror attacks
by pre-emptive
attacks") is abused already in the first instance of its implementation by
less than air-tight and
convincing intelligence.
* Faith-Based Intelligence, David Remnick, 03/07/21, The New Yorker
_________________________________________________________________
19.05. Intelligence Quagmire: How To Gauge The New IQ , The Christian
Science Monitor
Excerpts: For one thing, the unveiling of specific data about Iraq and its
dissection in the media
could make it harder to convince the spy services of other nations to
cooperate fully again with US
or British counterparts. (...) For another, the administration may now be
the White House that
cried wolf. (...) Thus many experts say it's important to get to the bottom
of what happened,
(...). If nothing else, Bush's new strategy of preemption, based on taking
out regimes posing
imminent threats, relies more on intelligence than on other tools.
* Intelligence Quagmire: How To Gauge The New IQ, Faye Bowers, Peter Grier,
03/07/21, The Christian
Science Monitor
_________________________________________________________________
20. Links & Snippets
_________________________________________________________________
20.01. Other Papers
_________________________________________________________________
20.02. Webcast Announcements
New Santa Fe Institute President About His Vision for SFI's Future Role,
(Video, Santa Fe, NM,
03/06/04) Edge Videos Einstein And Poincaré, Peter Galison,
03/06/
Genome Changes
Everything, Matt Ridley, 03/06/ A United Biology, E.O. Wilson, 03/05/28 In
The Matrix, Martin Rees,
03/05/19 Who Cares About Fireflies? Steven Strogatz, 03/05/12 World
Economic Forum Extraordinary
Annual Meeting, Jordan, 03/06/21-23 SPIE's 1st Intl Symp on Fluctuations
and Noise, Santa Fe, NM,
2003/06/01-04 NAS Sackler Colloquium on Mapping Knowledge Domains,
Video/Audio Report, 03/05/11
Uncertainty and Surprise: Questions on Working with the Unexpected and
Unknowable, The University
of Texas Austin, Texas USA, 2003/04/10-12 New Trends In Industrial
Partnership And Innovation
Management At European Research Laboratories, CERN, Geneva, 2003/03/19
(with webcast) CERN Webcast
Service, Streamed videos of Archived Lectures and Live Events Dean
LeBaron's Archive of Daily
Video Commentary, Ongoing Since February 1998
_________________________________________________________________
20.03. Conference & Call for Papers Announcements
Exystence Thematic Institute - Algorithms And Challenges In Hard
Combinatorial Problems - Trieste,
Italy, 03/07/01-31, Turin, Italy, 03/10/01-30 7th World Multi-Conference on
Systemics, Cybernetics
and Informatics (SCI 2003), Orlando, Florida, 2003/07/27-30 BIFURCATIONS
2003, Southampton, UK,
03/07/28-30 Intl Conf on Socio Political Informatics and Cybernetics: SPIC
'03, Orlando, Fl, USA,
2003/07/31-08/02 Leadership for Complex Changes - Seattle Conference,
Seattle, WA USA, 03/08/04-05
13th Annual International Conference, Soc f Chaos Theory in Psych &
Life Sciences,Boston, MA,
USA, 2003/08/08-10 Thematic Institute "Networks and Risks", Budapest,
Hungary, 03/08/25 - 09/27
Conference on Growing Networks and Graphs in Statistical Physics, Finance,
Biology and Social
Systems, Rome, 03/09/01-05 Call for Papers on Dynamical Hierarchies,
Special Issue of Artificial
Life, Deadline: 2003/09/05 7th European Conference on Artificial Life
(ECAL-2003), Dortmund,
Germany, 2003/09/14-17 A Dual International Conference on Ethics,
Complexity & Organisations
& Creativity, London, UK, 2003/09/17-18 1st German Conference on
Multiagent System Technologies
(MATES'03), Erfurt, Germany, 2003/09/22-25 Dynamics Days 2003, XXIII Annual
Conference, 4 Decades
of Chaos 1963-2003, Palma de Mallorca, Spain, 03/09/24-27 Improving The NHS
Through The Lens Of
Complexity, U Exeter, UK, 03/09/24-26 Emerging Technologies Conference at
MIT, Cambridge, MA,
2003/09/24-25 Intl School Mathematical Aspects of Quantum Chaos II Quantum
Chaos on Hyperbolic
Manifolds, Schloss Reisensburg (Günzburg, Germany), 03/10/04-11 2003
IEEE/WIC Intl Joint Conf.
Web Intelligence and Intelligent Agent Technology, Halifax, Canada,
2003/10/13-17 American Society
for Cybernetics (ASC) 2003 Conference (H.v.Foerster), Vienna, Austria ,
2003/11/10-15 Trends And
Perspectives In Extensive And Non-Extensive Statistical Mechanics, In
Honour Of The 60th Birthday
Of Constantino Tsallis, Angra Dos Reis, Brazil, 2003/11/19-21 ICDM '03: The
Third IEEE
International Conference on Data Mining, Melbourne, Florida, USA,
2003/11/19-22 4th Intl Conf on
Systems Science and Systems Engineering, Hong Kong, 03/11/25-28 3rd
International Workshop on
Meta-Synthesis and Complex System, Guangzhou, China, 2003/11/29-30 2nd
International Workshop on
the Mathematics and Algorithms of Social Insects, Georgia Tech, Atlanta,
Georgia, USA;
2003/12/15-17 1st International Workshop on Biologically Inspired
Approaches to Advanced
Information Technology, Lausanne, Switzerland, 04/01/29-30 4th Intl ICSC
Symposium Engineering Of
Intelligent Systems (EIS 2004), Island of Madeira, Portugal, 04/02/29-03/02
Fractal 2004,
"Complexity and Fractals in Nature", 8th Intl Multidisciplinary Conf ,
Vancouver, Canada,
2004/04/04-07 Urban Vulnerability and Network Failure: Constructions and
Experiences of
Emergencies, Crises and Collapse, Manchester, UK, 04/04/29-30 Fifth
International Conference on
Complex Systems (ICCS2004), Boston, MA, USA, 2004/05/16-21 13th
International Symposium on HIV
& Emerging Infectious Diseases, Toulon, France, 04/06/03-05
_________________________________________________________________
20.04. ComDig Announcement: New ComDig Archive in Beta Test
We are in the process of upgrading the Complexity Digest archives to a
format with improved search
capabilities. Also, we will finally be able to adequately publish the
valuable feedback and
comments from our knowledgable readers. You are cordially invited to become
a beta tester of our
new ComDig2 archive.
_________________________________________________________________
Complexity Digest is an independent publication available to organizations
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