14-05-2013 | David Wacey; Nicola McLoughlin; Matt R. Kilburn; Martin Saunders; John B. Cliff; Charlie Kong; Mark E. Barley; Marti ..., Proceedings of the National Academy of Sciences current issue, 2013

The 1.88-Ga Gunflint biota is one of the most famous Precambrian microfossil lagerstätten and provides a key record of the biosphere at a time of changing oceanic redox structure and chemistry. Here, we report on pyritized replicas of the iconic autotrophic Gunflintia–Huroniospora microfossil ...

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14-05-2013 | Annika Leifert; Yu Pan; Anne Kinkeldey; Frank Schiefer; Julia Setzler; Olaf Scheel; Hera Lichtenbeld; Günter Schmid; ..., Proceedings of the National Academy of Sciences current issue, 2013

Understanding the mechanism of toxicity of nanomaterials remains a challenge with respect to both mechanisms involved and product regulation. Here we show toxicity of ultrasmall gold nanoparticles (AuNPs). Depending on the ligand chemistry, 1.4-nm-diameter AuNPs failed electrophysiology-based ...

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14-05-2013 | Sammual Yu-Lut Leung; Wai Han Lam; Vivian Wing-Wah Yam, Proceedings of the National Academy of Sciences current issue, 2013

Platinum(II)-containing complexes with inherently chiral binaphthol derivatives display a versatile scaffold between random coils and single-turn helical strands, in which the conformational transition is controlled by the Pt···Pt and π−π interactions of alkynylplatinum(II) terpyridine moiety ...

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07-05-2013 | Kimberly A. Prather; Timothy H. Bertram; Vicki H. Grassian; Grant B. Deane; M. Dale Stokes; Paul J. DeMott; Lihini I ..., Proceedings of the National Academy of Sciences current issue, 2013

The production, size, and chemical composition of sea spray aerosol (SSA) particles strongly depend on seawater chemistry, which is controlled by physical, chemical, and biological processes. Despite decades of studies in marine environments, a direct relationship has yet to be established ...

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07-05-2013 | Proceedings of the National Academy of Sciences current issue, 2013

Ocean-atmosphere facility replicates sea spray aerosolsSea spray aerosol particles vary greatly in size and chemical composition. Decades of study have revealed many of the complex physical, chemical, and biological processes that determine seawater chemistry, yet researchers have been unable ...

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07-05-2013 | Guangchuan Wang; Rui-Yuan Cao; Rong Chen; Lijuan Mo; Jian-Feng Han; Xiaoyu Wang; Xurong Xu; Tao Jiang; Yong-Qiang De ..., Proceedings of the National Academy of Sciences current issue, 2013

The development of vaccines against infectious diseases represents one of the most important contributions to medical science. However, vaccine-preventable diseases still cause millions of deaths each year due to the thermal instability and poor efficacy of vaccines. Using the human ...

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23-04-2013 | Kyla M. Dahlin; Gregory P. Asner; Christopher B. Field, Proceedings of the National Academy of Sciences current issue, 2013

Understanding how and why plant communities vary across space has long been a goal of ecology, yet parsing the relative importance of different influences has remained a challenge. Species-specific models are not generalizable, whereas broad plant functional type models lack important detail. ...

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23-04-2013 | Ding Pan; Leonardo Spanu; Brandon Harrison; Dimitri A. Sverjensky; Giulia Galli, Proceedings of the National Academy of Sciences current issue, 2013

Water is a major component of fluids in the Earth’s mantle, where its properties are substantially different from those at ambient conditions. At the pressures and temperatures of the mantle, experiments on aqueous fluids are challenging, and several fundamental properties of water are poorly ...

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23-04-2013 | Melissa H. Pespeni; Eric Sanford; Brian Gaylord; Tessa M. Hill; Jessica D. Hosfelt; Hannah K. Jaris; Michèle LaVigne ..., Proceedings of the National Academy of Sciences current issue, 2013

Rising atmospheric carbon dioxide (CO2) conditions are driving unprecedented changes in seawater chemistry, resulting in reduced pH and carbonate ion concentrations in the Earth’s oceans. This ocean acidification has negative but variable impacts on individual performance in many marine ...

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23-04-2013 | Annika Elsen; Sven Festersen; Benjamin Runge; Christian T. Koops; Benjamin M. Ocko; Moshe Deutsch; Oliver H. Seeck; ..., Proceedings of the National Academy of Sciences current issue, 2013

Crystal nucleation and growth at a liquid–liquid interface is studied on the atomic scale by in situ Å-resolution X-ray scattering methods for the case of liquid Hg and an electrochemical dilute electrolyte containing Pb2+, F−, and Br− ions. In the regime negative of the Pb amalgamation ...

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