Catálogo de publicaciones - revistas

<jats:p>The recent debates over H5N1 experiments highlight current shortcomings in oversight of potential dual-use research.</jats:p>

<jats:p>Adaptation to cold temperature is mediated by RNA editing of a potassium channel in octopus neurons.</jats:p>

<jats:p>A comprehensive survey of the human genome reveals variations that disrupt protein-coding genes.</jats:p>

<jats:p>Oxidations of aliphatic C–H bonds, known since the 1800s, have only recently been considered for use in organic synthesis.</jats:p>

<jats:p>What characterized the first photosynthetic eukaryotes?</jats:p>

<jats:p>Changes in the lithium isotope composition of seawater over the past 70 million years elucidate the links between weathering and climate.</jats:p>

<jats:p>A population geneticist is remembered by colleagues for his generosity, clarity, and influence in the field, as well as in policy matters involving genetics.</jats:p>

<jats:title>Supramolecular Polymers Explained</jats:title> <jats:p> While polymers are constructed from chemically bonded units, supramolecular polymers arise through reversible linkages, such as hydrogen bonding and electrostatic interactions. Recent advances in the field of supramolecular polymer science have moved from a fundamental understanding of assembly properties to the introduction of functionality, in order to exploit the particular features of this class of materials. <jats:bold> Aida <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="813" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1205962">813</jats:related-article> ) review the specific features of supramolecular polymers that can lead to applications in a variety of fields, including: materials—in which processability and self-healing properties are of interest; biomedicine—in which the concerns are dynamic functionality and biodegradability; and hierarchical assembly and electronic systems—with an interest in unidirectionality of charge flow. </jats:p>

<jats:title>Life of Li</jats:title> <jats:p> Because lithium primarily exists in silicate minerals on continents, the variations of Li isotopes in marine sedimentary rocks reflect the degree of silicate weathering and formation of new sediments on the seafloor, which in turn are largely controlled by climate and tectonic forces over geologic time. By analyzing sedimentary cores from eight drill sites around the world's oceans, <jats:bold>Misra and Froelich</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="818" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1214697">818</jats:related-article> , published online 26 January; see the cover; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6070" page="810" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1218342">Paytan</jats:related-article> </jats:bold> ) assembled a 68-million-year record of the Li isotope composition of seawater. The record reveals a stepwise change in the Li isotopic ratio, suggesting that several intense episodes of tectonic uplift increased continental weathering rates and delivery of sediments to the oceans. Abrupt swings in the record at specific points in Earth's history, for example, around the time when dinosaurs became extinct, imply major changes in ocean chemistry—but their mechanisms remain enigmatic. </jats:p>

<jats:title>Defective Gene Detective</jats:title> <jats:p> Identifying genes that give rise to diseases is one of the major goals of sequencing human genomes. However, putative loss-of-function genes, which are often some of the first identified targets of genome and exome sequencing, have often turned out to be sequencing errors rather than true genetic variants. In order to identify the true scope of loss-of-function genes within the human genome, <jats:bold> MacArthur <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="823" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1215040">823</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6070" page="823" related-article-type="in-this-issue" vol="335" xlink:href="10.1126/science.1215040">Quintana-Murci</jats:related-article> </jats:bold> ) extensively validated the genomes from the 1000 Genomes Project, as well as an additional European individual, and found that the average person has about 100 true loss-of-function alleles of which approximately 20 have two copies within an individual. Because many known disease-causing genes were identified in “normal” individuals, the process of clinical sequencing needs to reassess how to identify likely causative alleles. </jats:p>