PubMed · 15944681
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George F R Ellis. 2005-06-09. Physics, complexity and causality.. https://doi.org/10.1038/435743a
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Latin America has experienced a vigorous growth in scientific production since the 1990s, rising from 1.7% of the world's share of science publications in 1990 to 3.2% in 2000. This appears to be a consequence of increasing investment in tertiary education, especially at the doctoral level. However, such growth is not homogeneous among the nations of Latin America, being affected by many issues, such as economical power and expenses in science and technology. Biology--including comparative biochemistry and physiology (CBP)--is one of the scientific areas of tremendous growth in the continent. Thus, in order to celebrate the increasing participation of Latin America in the field of CBP, the editorial board of Comp. Biochem. Physiol. decided to organize a special volume dedicated to Latin American authors (CBP-Latin America). From May to November 2005, 52 manuscripts were submitted to CBP-Latin America from Argentina, Brazil, Chile, Cuba, Mexico, Uruguay and Venezuela. This opening issue contains the first two dozen manuscripts, highlighting the diversity of experimental approaches and the breadth and uniqueness of the biological systems available to researchers in Latin America. We hope that the CBP-Latin America project becomes a significant editorial initiative, one that will meet the goals of highlighting, integrating, and mapping CBP research in Latin America.
BioModels Database (http://www.ebi.ac.uk/biomodels/), part of the international initiative BioModels.net, provides access to published, peer-reviewed, quantitative models of biochemical and cellular systems. Each model is carefully curated to verify that it corresponds to the reference publication and gives the proper numerical results. Curators also annotate the components of the models with terms from controlled vocabularies and links to other relevant data resources. This allows the users to search accurately for the models they need. The models can currently be retrieved in the SBML format, and import/export facilities are being developed to extend the spectrum of formats supported by the resource.
Low frequency magnetic fields can influence biochemical reactions and consequently physiological rhythms and oscillations. To test this for a model reaction we used the chemical Belousov-Zhabotinsky (BZ) reaction, which is one of the simplest chemical oscillators. The oscillation frequency of the reaction was tracked optically by the absorption of blue light. Field treatment was carried out at room temperature in the middle of two Helmholtz coils. After starting the reaction, for 5 min the oscillations were monitored as control measurement, then during the next 10 min monitoring was with a magnetic field switched on, followed by a period of 5 min with the field switched off. A variety of exposure conditions have been tested: the frequency was varied between 5 and 1000 Hz, the field strength was varied up to 2.7 mT, different pulse shapes were used, the influence of the exposure temperature was tested, and the influence of the optimum exposure conditions (static magnetic field and the frequency of the dynamic field) as predicted by the ion parametric resonance (IPR) model has been measured. In conclusion, in no case any statistical significant influence of the magnetic treatment on the oscillation frequency of the BZ reaction could be detected (P > .05, t-test).