Catálogo de publicaciones - revistas

<jats:p>"Predatory" conferences—meetings, sometimes sparsely attended, that seem to come into being primarily to make money—have become a cottage industry in scientific communication.</jats:p>

<jats:p>Bonnie Bassler and Larry Smarr have a gift for enthralling audiences. They share advice on how to make powerful public presentations.</jats:p>

<jats:p>Bonnie Bassler and Larry Smarr have a gift for enthralling audiences. They share advice on how to make powerful public presentations.</jats:p>

<jats:p>Despite predictions that emerging technologies will transform how research is conducted, disseminated, and rewarded, why do we see so little actual shift in how scholars in the most competitive and aspirant institutions actually disseminate their research? I describe research on faculty values and needs in scholarly communication that confirm a number of conservative tendencies in publishing. These tendencies, influenced by tenure and promotion requirements, as well as disciplinary cultures, have both positive and negative consequences. Rigorous research could inform development of good practices and policies in academic publishing, as well as counter rhetoric concerning the future of peer review and scholarly communication.</jats:p>

<jats:title>Resetting the Circadian Clock</jats:title> <jats:p> Fatigue and other symptoms of jet lag arise when the body's internal circadian clock is out of sync with environmental light-dark cycles. Studying genetically modified mice lacking two receptors for the peptide hormone vasopressin under experimental conditions simulating jet lag, <jats:bold> Yamaguchi <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6154" page="85" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1238599">85</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="6154" page="52" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1245474">Hastings</jats:related-article> </jats:bold> ) concluded that vasopressin signaling in the suprachiasmatic nucleus (SCN)—a region of the brain known to control circadian rhythms—impedes adjustment to the environmental clock. Infusion of vasopressin receptor antagonists directly into the SCN of wild-type mice accelerated their recovery from jet lag, suggesting that this pathway may merit further investigation as a pharmacological target for treating jet lag. </jats:p>

<jats:title>Gas Separations</jats:title> <jats:p> When gas separation membranes are made thinner, they usually allow permeating gases to pass through faster. However, a thinner membrane may be poorer at separating between gas species. <jats:bold> Kim <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6154" page="91" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1236098">91</jats:related-article> ) examined the permeability and selectivity of layered graphene and graphene oxide membranes. Gas molecules diffuse through defective pores and channels that form between the layers. Controlling these structures tuned the properties of the membranes to allow the extraction of carbon dioxide from other gases. <jats:bold> Li <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6154" page="95" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1236686">95</jats:related-article> ) describe membranes as thin as 1.8 nanometers made from only two to three layers of graphene oxide. Small defects within the layers allowed hydrogen to pass through, separating it from carbon dioxide and nitrogen. </jats:p>

<jats:title>Gas Separations</jats:title> <jats:p> When gas separation membranes are made thinner, they usually allow permeating gases to pass through faster. However, a thinner membrane may be poorer at separating between gas species. <jats:bold> Kim <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6154" page="91" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1236098">91</jats:related-article> ) examined the permeability and selectivity of layered graphene and graphene oxide membranes. Gas molecules diffuse through defective pores and channels that form between the layers. Controlling these structures tuned the properties of the membranes to allow the extraction of carbon dioxide from other gases. <jats:bold> Li <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6154" page="95" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1236686">95</jats:related-article> ) describe membranes as thin as 1.8 nanometers made from only two to three layers of graphene oxide. Small defects within the layers allowed hydrogen to pass through, separating it from carbon dioxide and nitrogen. </jats:p>

<jats:title>Reactive Conformations</jats:title> <jats:p> Most molecules manifest a fair amount of flexibility at room temperature, in particular through interconversion of rotational conformers—structures that differ by the relative orientation of groups on either side of a single covalent bond. <jats:bold> Chang <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6154" page="98" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1242271">98</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="6154" page="46" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1244833">Heaven</jats:related-article> </jats:bold> ) devised a method to explore the comparative reactivities of different conformers. A mixture of the conformers was prepared in a molecular beam cold enough to preclude interconversion; then an electric field was used to push the different conformers apart, spatially resolving subsequent collisional interactions with a target of trapped ions. </jats:p>

<jats:title>Same As It Ever Was</jats:title> <jats:p> Nitrogen constitutes approximately 78% by volume of Earth's atmosphere and is a key component in its chemical and physical characteristics. It is not clear whether N <jats:sub>2</jats:sub> has been so abundant throughout Earth's geological history. <jats:bold> Marty <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6154" page="101" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1240971">101</jats:related-article> , published online 19 September) analyzed the isotopic compositions of nitrogen and argon from fluid inclusions trapped in hydrothermal quartz formed 3 to 3.5 billion years ago. The partial pressure and isotopic composition of atmospheric N <jats:sub>2</jats:sub> were similar to today's. Thus, other factors are needed to explain why liquid water existed on Earth's surface despite the Sun being 30% less luminous. </jats:p>

<jats:title>Two Are Not Necessarily Better Than One</jats:title> <jats:p> Gene duplication is one of the major drivers of the evolution of gene and protein networks. However, specific examples of how genes change to maintain two paralogous gene copies within an organism are relatively rare. <jats:bold> Baker <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6154" page="104" related-article-type="in-this-issue" vol="342" xlink:href="10.1126/science.1240810">104</jats:related-article> ) examined the functional divergence of the paralogs Mcm1 and Arg80, MADS-box transcription factors in the yeast <jats:italic>Saccharomyces cerevisiae</jats:italic> . The partitioning of ancestral functions in a fungal transcription factor appeared to be affected by competitive interference between the newly formed gene duplicates. Thus, in yeast, gene duplication has created a selective conflict between the paralogs, which appear to have driven the evolution of a novel protein function. </jats:p>