Artículos con la etiqueta ‘biología’

Quantum biology on the edge of quantum chaos

Por • 4 abr, 2012 • Category: Ambiente

We give a new explanation for why some biological systems can stay quantum coherent for long times at room temperatures, one of the fundamental puzzles of quantum biology. We show that systems with the right level of complexity between chaos and regularity can increase their coherence time by orders of magnitude. Systems near Critical Quantum Chaos or Metal-Insulator Transition (MIT) can have long coherence times and coherent transport at the same time. The new theory tested in a realistic light harvesting system model can reproduce the scaling of critical fluctuations reported in recent experiments. Scaling of return probability in the FMO light harvesting complex shows the signs of universal return probability decay observed at critical MIT. The results may open up new possibilities to design low loss energy and information transport systems in this Poised Realm hovering reversibly between quantum coherence and classicality.

L’hypothétique mutation à la source du succès évolutif des hominidés

Por • 28 ago, 2011 • Category: Opinion

Pat Shipman a récemment proposé de compléter cette première explication par une autre, exposée dans son livre «The Animal Connection. A new perspective on what makes us human» (W.W. Norton and Co, juin 2011). Elle ne remet pas en cause l’explication de l’hominisation par l’usage de l’outil, mais elle propose d’ajouter un facteur explicatif tout aussi puissant selon elle : la coopération qui s’est établie des les origines entre les hominiens et différentes espèces animales les ayant aidé à s’imposer dans un monde peuplé initialement de prédateurs redoutables.

Du génome du singe au génome humain

Por • 8 abr, 2011 • Category: Ciencia y tecnología

A partir de ces premières recherches, ils ont identifié un nombre apparemment considérables d’exemples (508), montrant que le génome humain se différenciait de celui des autres espèces non par l’ajout de nouvelles séquences de régulation mais par la disparition ou l’inhibition de séquences actives dans les autres espèces. Autrement dit, ce ne fut pas par l’addition de nouveaux gènes ou nouvelles séquences d’ADN que les hominidés se sont spécifiés, mais par la soustraction de gènes et séquences présents depuis des millions d’années chez les autres espèces.

Consciousness: A Direct Link with Life’s Origin?

Por • 1 mar, 2011 • Category: Opinion

Inspired by the Penrose-Hameroff thesis, we are intuitively led to examine an intriguing correspondence of ‘induction’ (by fields), with the complex phenomenon of (metabolism-sustained) consciousness

Temperature Dependence of Protein Folding Deduced from Quantum Transition

Por • 25 feb, 2011 • Category: Leyes

A general formula on the rate-temperature dependence has been deduced which is in good accordance with experimental data. These temperature dependences are further analyzed in terms of torsion potential parameters.

Wright’s adaptive landscape versus Fisher’s fundamental theorem

Por • 25 feb, 2011 • Category: Filosofía

The Wright-Fisher controversy forms a cornerstone of the history and philosophy of biology. This key contrast between embodied theories of real cases and abstract laws is missing from prior analyses of Wright versus Fisher. They never argued about this contrast. Instead, the issue at stake in their arguments concerned the actual dynamics of real populations.

The Computing of Digital Ecosystems

Por • 8 feb, 2011 • Category: Ambiente

A primary motivation for our research in digital ecosystems is the desire to exploit the self-organising properties of biological ecosystems. Ecosystems are thought to be robust, scalable architectures that can automatically solve complex, dynamic problems. However, the computing technologies that contribute to these properties have not been made explicit in digital ecosystems research.

an Lagrangian Systems be Better than Hamiltonian Systems at Approximating Biological Evolution?

Por • 7 feb, 2011 • Category: Ambiente

Evolutionary processes and their major features have commonalities with a diverse range of physical phenomena. Models of fitness or adaptation currently used in theoretical biology are similar to Hamiltonian-based representations of dynamical systems in terms of inspiration and major assumptions.

Giant Virus, Tiny Protein Crystals Show X-ray Laser’s Power and Potential

Por • 4 feb, 2011 • Category: Ciencia y tecnología

Two studies to be published February 3 in Nature demonstrate how the unique capabilities of the world’s first hard X-ray free-electron laser—the Linac Coherent Light Source, located at the Department of Energy’s SLAC National Accelerator Laboratory—could revolutionize the study of life.

Evidence of strategic periodicities in collective conflict dynamics

Por • 17 ene, 2011 • Category: Leyes

We demonstrate the existence of periodicities that are not directly coupled to environmental cycles or known ultraridian mechanisms.