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The deep history of the number words
We have previously shown that the âlow limitâ number words (from one to five)
have exceptionally slow rates of lexical replacement when measured across the
Indo-European (IE) languages. Here, we replicate this finding within the Bantu
and Austronesian language families, and with new data for the IE languages.
Number words can remain stable for 10 000 to over 100 000 years, or around
3.5â20 times longer than average rates of lexical replacement among the
Swadesh list of âfundamental vocabularyâ items. Ordinal evidence suggests
that number words also have slow rates of lexical replacement in the Pamaâ
Nyungan language family of Australia. We offer three hypotheses to explain
these slow rates of replacement: (i) that the abstract linguistic-symbolic processing
of ânumberâ links to evolutionarily conserved brain regions associated
with numerosity; (ii) that number words are unambiguous and therefore
have lower âmutation ratesâ; and (iii) that the number words occupy a region
of the phonetic space that is relatively full and therefore resist change because
alternatives are unlikely to be as âgoodâ as the original word.
This article is part of a discussion meeting issue âThe origins of numerical
abilitiesâ
World-Wide Web scaling exponent from Simon's 1955 model
Recently, statistical properties of the World-Wide Web have attracted
considerable attention when self-similar regimes have been observed in the
scaling of its link structure. Here we recall a classical model for general
scaling phenomena and argue that it offers an explanation for the World-Wide
Web's scaling exponent when combined with a recent measurement of internet
growth.Comment: 1 page RevTeX, no figure
Feature selection and novelty in computational aesthetics
[Abstract] An approach for exploring novelty in expression-based evolutionary art systems is presented. The framework is composed of a feature extractor, a classifier, an evolutionary engine and a supervisor. The evolutionary engine exploits shortcomings of the classifier, generating misclassified instances. These instances update the training set and the classifier is re-trained. This iterative process forces the evolutionary algorithm to explore new paths leading to the creation of novel imagery. The experiments presented and analyzed herein explore different feature selection methods and indicate the validity of the approach.Portugal. Fundação para a CiĂȘncia e a Tecnologia; PTDC/EIAâEIA/115667/2009Galicia.ConsellerĂa de InnovaciĂłn, Industria e Comercio ; PGIDIT10TIC105008P
Mechanical mode dependence of bolometric back-action in an AFM microlever
Two back action (BA) processes generated by an optical cavity based detection
device can deeply transform the dynamical behavior of an AFM microlever: the
photothermal force or the radiation pressure. Whereas noise damping or
amplifying depends on optical cavity response for radiation pressure BA, we
present experimental results carried out under vacuum and at room temperature
on the photothermal BA process which appears to be more complex. We show for
the first time that it can simultaneously act on two vibration modes in
opposite direction: noise on one mode is amplified whereas it is damped on
another mode. Basic modeling of photothermal BA shows that dynamical effect on
mechanical mode is laser spot position dependent with respect to mode shape.
This analysis accounts for opposite behaviors of different modes as observed
Power-law distributions and Levy-stable intermittent fluctuations in stochastic systems of many autocatalytic elements
A generic model of stochastic autocatalytic dynamics with many degrees of
freedom is studied using computer simulations. The time
evolution of the 's combines a random multiplicative dynamics at the individual level with a global coupling through a
constraint which does not allow the 's to fall below a lower cutoff given
by , where is their momentary average and is a
constant. The dynamic variables are found to exhibit a power-law
distribution of the form . The exponent
is quite insensitive to the distribution of the random factor
, but it is non-universal, and increases monotonically as a function
of . The "thermodynamic" limit, N goes to infty and the limit of decoupled
free multiplicative random walks c goes to 0, do not commute:
for any finite while (which is the common range
in empirical systems) for any positive . The time evolution of exhibits intermittent fluctuations parametrized by a (truncated)
L\'evy-stable distribution with the same index . This
non-trivial relation between the distribution of the 's at a given time
and the temporal fluctuations of their average is examined and its relevance to
empirical systems is discussed.Comment: 7 pages, 4 figure
Interpretation of plasma amino acids in the follow-up of patients: the impact of compartmentation
Results of plasma or urinary amino acids are used for suspicion, confirmation or exclusion of diagnosis, monitoring of treatment, prevention and prognosis in inborn errors of amino acid metabolism. The concentrations in plasma or whole blood do not necessarily reflect the relevant metabolite concentrations in organs such as the brain or in cell compartments; this is especially the case in disorders that are not solely expressed in liver and/or in those which also affect nonessential amino acids. Basic biochemical knowledge has added much to the understanding of zonation and compartmentation of expressed proteins and metabolites in organs, cells and cell organelles. In this paper, selected old and new biochemical findings in PKU, urea cycle disorders and nonketotic hyperglycinaemia are reviewed; the aim is to show that integrating the knowledge gained in the last decades on enzymes and transporters related to amino acid metabolism allows a more extensive interpretation of biochemical results obtained for diagnosis and follow-up of patients and may help to pose new questions and to avoid pitfalls. The analysis and interpretation of amino acid measurements in physiological fluids should not be restricted to a few amino acids but should encompass the whole quantitative profile and include other pathophysiological markers. This is important if the patient appears not to respond as expected to treatment and is needed when investigating new therapies. We suggest that amino acid imbalance in the relevant compartments caused by over-zealous or protocol-driven treatment that is not adjusted to the individual patient's needs may prolong catabolism and must be correcte
From Social Data Mining to Forecasting Socio-Economic Crisis
Socio-economic data mining has a great potential in terms of gaining a better
understanding of problems that our economy and society are facing, such as
financial instability, shortages of resources, or conflicts. Without
large-scale data mining, progress in these areas seems hard or impossible.
Therefore, a suitable, distributed data mining infrastructure and research
centers should be built in Europe. It also appears appropriate to build a
network of Crisis Observatories. They can be imagined as laboratories devoted
to the gathering and processing of enormous volumes of data on both natural
systems such as the Earth and its ecosystem, as well as on human
techno-socio-economic systems, so as to gain early warnings of impending
events. Reality mining provides the chance to adapt more quickly and more
accurately to changing situations. Further opportunities arise by individually
customized services, which however should be provided in a privacy-respecting
way. This requires the development of novel ICT (such as a self- organizing
Web), but most likely new legal regulations and suitable institutions as well.
As long as such regulations are lacking on a world-wide scale, it is in the
public interest that scientists explore what can be done with the huge data
available. Big data do have the potential to change or even threaten democratic
societies. The same applies to sudden and large-scale failures of ICT systems.
Therefore, dealing with data must be done with a large degree of responsibility
and care. Self-interests of individuals, companies or institutions have limits,
where the public interest is affected, and public interest is not a sufficient
justification to violate human rights of individuals. Privacy is a high good,
as confidentiality is, and damaging it would have serious side effects for
society.Comment: 65 pages, 1 figure, Visioneer White Paper, see
http://www.visioneer.ethz.c
Species abundance distributions: moving beyond single prediction theories to integration within an ecological framework
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75247/1/j.1461-0248.2007.01094.x.pd
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