During the summers of 2009 and 2013, seawater pH and concentrations of dissolved oxygen, inorganic carbon, and nutrients were measured off the Changjiang estuary in the East China Sea. The 2009 cruise captured the effects of Typhoon Morakot; the 2013 cruise sampled more typical conditions (no typhoon). Data from both years indicate a close correlation between high primary productivity in surface waters and hypoxia in bottom waters. Based on these observations, we developed a conceptual model to guide an exploration of processes contributing to the formation of summertime bottom hypoxia. A mixing-model analysis of the 2009 data identified a surface diatom bloom as the major (70-80%) source of the organic carbon that decomposed and ultimately led to bottom water hypoxia. Within the Changjiang River plume, depth-integrated net biological production in the water column was 1.8 g C m 22 d 21 , indicating strong autotrophic production, which in turn led to a high respiration rate of 1.2 g C m 22 d 21 in the bottom water. During both cruises, strong surface-to-bottom physical and metabolic coupling was evident. In 2009, storm-driven inputs of nutrients from elevated river discharge and strong vertical mixing helped to fuel the rapid development of a surface diatom bloom. Afterwards, stratified conditions re-established, newly formed labile organic matter sank, and bottom water oxygen was quickly consumed to an extent that hypoxia and acidification developed. To our knowledge, the observed rate of hypoxia and acidification development (within 6 d) is the fastest yet reported for the Changjiang River plume.Oxygen-minimum zones in open-ocean waters and hypoxic zones in coastal waters have received increased attention in recent research related to changing biogeochemical and climate conditions. Oceanic oxygen-minimum zones occur naturally and permanently at depths of 200-1000 m in the open ocean (Wyrtki 1962). In contrast, coastal hypoxia (dissolved oxygen [DO] <63 lmol L 21 ) appears seasonally and is believed to be largely associated with anthropogenic eutrophication. Where nutrient inputs to coastal waters result in excess primary production, depletion of oxygen in bottom waters may follow (Diaz and Rosenberg 2008; Bianchi et al.

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The anatomical description provided here may provide a more accurate theoretical foundation for clinical subtalar stability restoration.

Sediment traps were deployed at 870 m water-depth from August 2008 to September at station DM in the Chukchi Sea (western Arctic Ocean) in an area covered by sea ice in winter to determine seasonal fluxes of HBIs and phytoplankton sterols in order to improve our understanding of sea ice proxies. HBI-III fluxes and P III IP 25 are for the first time documented in the Arctic Ocean to evaluate their significance for paleoclimate reconstructions. Highest mass fluxes were found from mid-July 2009 to September 2009 contrasting with low values during all other months (i.e., December 2008 to early July 2009). Indeed, during the winter months IP 25 was not detected but increased by a factor of nine over summer 2009 reflecting sea ice algae and pelagic phytoplankton production at the sea ice edge. High HBIs and low sterol fluxes at the end of summer 2008 are consistent with the complete melting of sea ice and post-bloom conditions. We found that HBI-III was more abundant in the early stage of sea ice retreat that characterizes the marginal ice zone. These sea ice biomarkers were also measured in surface sediments across a wide range of sea ice cover in the western Arctic region. Higher IP 25 values were found in the southeastern Chukchi Sea and decreased westwards where sea ice conditions are less severe. Stronger positive linear relationship were found between the sea ice proxy indexes P B IP 25 and P III IP 25 and spring sea ice concentrations than with IP 25 in agreement with earlier findings from other Arctic and sub-Arctic regions.

Fullerenol, an important water-soluble derivative of fullerene carbon nanomaterial, has been increasingly used in medicine and industry. The presence and release of carbon nanoparticles into the environment have raised concerns over potential impacts on human health and the environment. In this study, the bioaccumulation of fullerenol nanoparticles in wheat was investigated using 13 C-labelling techniques. The dose and time-dependent bioaccumulation of fullerenol in wheat was observed, and most fullerenol (about 85.68-263.86% ID per g, percentage of dose per gram tissue) was found in roots. With prolonged culture times, the seedlings treated with relatively low concentrations of fullerenol nanoparticles (2.5 μg mL −1 ) showed significant increases in 13 C content in roots, while 10.0 μg mL −1 fullerenol appeared to suppress this accumulation. Only very limited amounts (<4.13% ID per g) of fullerenol nanoparticles were translocated from roots to stems and leaves. The presence of fullerenol nanoparticles was confirmed by scanning electron microscopy, and small particles were found in the vascular cylinder of wheat roots. During the incubations with fullerenol nanoparticles at all test concentrations, the biomass gain of stems and leaves was unaffected, while root elongation was promoted. Fullerenol also improved the synthesis of chlorophyll in wheat during the 7 d observation period.Environ. Sci.: Nano This journal isAs an important water-soluble derivative of fullerene carbon nanomaterial, fullerenol has been increasingly used in the field of medicine and in industry, but the environmental impact of fullerenol has seldom been investigated. Herein, the bioaccumulation of fullerenol nanoparticles in wheat was investigated using 13 C-labelling techniques. The dose and time dependent bioaccumulation of fullerenol in wheat was observed, while the majority of particles (about 85.68-263.86% ID per g, percentage of dose per gram tissue) were only found in the roots and very limited amounts (<4.13% ID per g) could translocate from the roots to stems and leaves. Fullerenol promoted root elongation and chlorophyll synthesis.

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