sábado, 12 de mayo de 2012

Compilado AZyNE 12/5


Peopling the planet


Few question the idea that modern humans are all emigrants from Africa. But when their journey began, when it ended and what they did along the way makes for a deepening mystery, explored in this issue of Nature.
 
Nature 485, 23 (03 May 2012) http://dx.doi.org/10.1038/485023a


Rise and Demise of Bioinformatics? Promise and Progress

The field of bioinformatics and computational biology has gone through a number of transformations during the past 15 years, establishing itself as a key component of new biology. This spectacular growth has been challenged by a number of disruptive changes in science and technology. Despite the apparent fatigue of the linguistic use of the term itself, bioinformatics has grown perhaps to a point beyond recognition. We explore both historical aspects and future trends and argue that as the field expands, key questions remain unanswered and acquire new meaning while at the same time the range of applications is widening to cover an ever increasing number of biological disciplines. These trends appear to be pointing to a redefinition of certain objectives, milestones, and possibly the field itself.
 
Ouzounis CA (2012) Rise and Demise of Bioinformatics? Promise and Progress. PLoS Comput Biol 8(4): e1002487. http://dx.doi.org/10.1371/journal.pcbi.1002487

Sexual selection enables long-term coexistence despite ecological equivalence

Empirical data indicate that sexual preferences are critical for maintaining species boundaries, yet theoretical work has suggested that, on their own, they can have only a minimal role in maintaining biodiversity. This is because long-term coexistence within overlapping ranges is thought to be unlikely in the absence of ecological differentiation9. Here we challenge this widely held view by generalizing a standard model of sexual selection to include two ubiquitous features of populations with sexual selection: spatial variation in local carrying capacity, and mate-search costs in females.

Sexual selection enables long-term coexistence despite ecological equivalence
Leithen K. M’Gonigle, Rupert Mazzucco, Sarah P. Otto & Ulf Dieckmann
Nature 484, 506–509 (26 April 2012) http://dx.doi.org/10.1038/nature10971

Controversial research: Good science bad science


It sounds like a great idea: experimentally mutate a rare but deadly virus so that scientists can do a better job of recognizing dangerous emerging strains. But it also sounds like a terrible idea — the studies could create a virus that is easier to transmit and produce findings that are useful to bioterrorists.

Controversial research: Good science bad science
Geoff Brumfiel
Nature 484, 432–434 (26 April 2012) http://dx.doi.org/10.1038/484432a





The Emergence of Modularity in Biological Systems

In this review, we discuss modularity and hierarchy in biological systems. We review examples from protein structure, genetics, and biological networks of modular partitioning of the geometry of biological space. We review theories to explain modular organization of biology, with a focus on explaining how biology may spontaneously organize to a structured form. That is, we seek to explain how biology nucleated from among the many possibilities in chemistry.

The Emergence of Modularity in Biological Systems
Dirk M. Lorenz, Alice Jeng, Michael W. Deem


Origins of evolution: Non-acquired characters dominates over acquired characters in changing environment


We explored competition between acquired (AQ) versus non-acquired (NAQ) character inheritance. We established that NAQ evolution rule is dominating in case of changing environment.
Origins of evolution: Non-acquired characters dominates over acquired characters in changing environment. Cédric Gaucherel, Henrik Jeldtoft Jensen. Journal of Theoretical Biology Volume 304, 7 July 2012, Pages 111–120. 

Beyond Turing's Machines

In marking Alan Turing's centenary, it's worth asking what was his most fundamental achievement and what he left for future science to take up when he took his own life in 1954. His success in World War II, as the chief scientific figure in the British cryptographic effort, with hands-on responsibility for the Atlantic naval conflict, had a great and immediate impact. But in its ever-growing influence since that time, the principle of the universal machine, which Turing published in 1937, beats even this.
 
Beyond Turing's Machines
Andrew Hodges
Science 13 April 2012: Vol. 336 no. 6078 pp. 163-164
http://dx.doi.org/10.1126/science.1218417



Dusting Off the Turing Test

Hold up both hands and spread your fingers apart. Now put your palms together and fold your two middle fingers down till the knuckles on both fingers touch each other. While holding this position, one after the other, open and close each pair of opposing fingers by an inch or so. Notice anything? Of course you did. But could a computer without a body and without human experiences ever answer that question or a million others like it? And even if recent revolutionary advances in collecting, storing, retrieving, and analyzing data lead to such a computer, would this machine qualify as “intelligent”?
 
Dusting Off the Turing Test
Robert M. French
Science 13 April 2012: Vol. 336 no. 6078 pp. 164-165
http://dx.doi.org/10.1126/science.1218350

Artificial Intelligence Could Be on Brink of Passing Turing Test


One hundred years after Alan Turing was born, his eponymous test remains an elusive benchmark for artificial intelligence. Now, for the first time in decades, it’s possible to imagine a machine making the grade.
Turing was one of the 20th century’s great mathematicians, a conceptual architect of modern computing whose codebreaking played a decisive part in World War II. His test, described in a seminal dawn-of-the-computer-age paper, was deceptively simple: If a machine could pass for human in conversation, the machine could be considered intelligent.