AAAS, Science NOW

This Week in Science -- Brief summaries of new research papers published in Science

The Planar Cell Polarity (PCP) signaling pathway governs cell movements that drive axis elongation and neural tube closure in vertebrate embryos, and certain vertebrate PCP proteins have also been implicated … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1253-a?rss=1">[Read more]</a>

Developmental processes can define repeated patterns of structure, such as somites in vertebrates. In plants, too, repeated structures arise during growth and development. As the above-ground shoot grows, it sends … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1253-b?rss=1">[Read more]</a>

In electronic circuitry, the band gap of a semi-conductor helps to provide the barrier that keeps charge carriers from flowing until a voltage is applied that switches the device. As … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1253-c?rss=1">[Read more]</a>

Among the first facts students learn about the natural world is that plants owe their green color to the pigment chlorophyll. There have actually been a handful of slightly different … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1253-d?rss=1">[Read more]</a>

Carbon nanotubes can function as chemical sensors by virtue of the shifts in resistance or capacitance induced when small molecules bind to their surfaces. Unfortunately, many molecules bind rather tightly, … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1253-e?rss=1">[Read more]</a>

Ion binding by proteins can exert a major influence on electron transfer events in biological systems. Park et al. (p. 1324) discovered an analogous phenomenon in a simpler synthetic system. … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1253-f?rss=1">[Read more]</a>

What would our climate future look like if we stopped building any new infrastructure that used fossil fuels? Davis et al. (p. 1330; see the Perspective by Hoffert) made the … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1253-g?rss=1">[Read more]</a>

In October 2010, the Convention on Biological Diversity will meet to assess the current condition of global biodiversity and to propose and agree on priorities for its future conservation. In … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1253-h?rss=1">[Read more]</a>

The ability to expand hematopoietic stem cells (HSCs) during ex-vivo culture has been an important goal for over 20 years. Using a high-throughput chemical screen, Boitano et al. (p. 1345, … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-a?rss=1">[Read more]</a>

Transient conformations are important to protein function; however, detecting and characterizing these states is technically challenging. Korzhnev et al. (p. 1312; see the Perspective by Al-Hashimi) combined recently developed methods … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-b?rss=1">[Read more]</a>

Efficient and accurate repair of double-strand DNA breaks is critical for genome stability and involves a process known as homologous recombination. During repair of the sheared ends, the DNA must … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-c?rss=1">[Read more]</a>

Many bacteria and archaea recognize invading viruses and plasmids. Foreign DNA is integrated into so-called clustered regularly interspaced short palindromic repeat (CRISPR) loci, and transcripts from these loci are processed … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-d?rss=1">[Read more]</a>

The growing appreciation that clinically abnormal behaviors in children and adolescents may be influenced or perhaps even initiated by developmental miscues has stoked an interest in mapping normal human brain … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-e?rss=1">[Read more]</a>

Theoretical studies have suggested that protons can be conducted rapidly in water trapped inside carbon nanotubes. C. Y. Lee et al. (p. 1320) connected two aqueous reservoirs with opened, single-walled … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-f?rss=1">[Read more]</a>

As a primary component of the martian atmosphere and as the primary greenhouse gas for Mars, carbon dioxide has played a role in climate and geological processes during martian history. … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-g?rss=1">[Read more]</a>

Filopodia are finger-like structures containing parallel bundles of actin filaments that are central to eukaryotic cell motility in a variety of contexts. K. Lee et al. (p. 1341) reconstituted filopodia-like … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-h?rss=1">[Read more]</a>

During their life cycle malaria parasites produce vast numbers of successive proliferative stages in their vertebrate hosts, and yet in the field most mosquitoes are free of parasites. Rodrigues et … <a href="http://www.sciencemag.org/cgi/content/full/329/5997/1255-i?rss=1">[Read more]</a>