21 research outputs found
Functions of height and width dimensions in the intertidal mussel, Mytilus californianus
Author Posting. © National Shellfisheries Association, 2008. This article is posted here by permission of National Shellfisheries Association for personal use, not for redistribution. The definitive version was published in Journal of Shellfish Research 27 (2008): 385-392, doi:10.2983/0730-8000(2008)27[385:FOHAWD]2.0.CO;2.A mussel's shell records its history of growth. We investigated variability in the size and shape of mussel shells of Mytilus californianus Conrad (1837) to test the hypothesis that the mussel shell provides information on the contemporary condition of the mussel. Two factors were associated with shape: an epithelial discoloration and the Sr/Ca in the shell nacre. Sr/Ca data distinguished the mussel populations as did a discriminate analysis that included the trace metal ratios; Sr/Ca, Mg/Ca, Mn/Ca, Ag/Ca, Cd/Ca, Ba/Ca, and Pb/Ca. Size varied independently of shape and was not associated with the two factors. However, a null model that describes the morphological variability in height and width suggests that mussel size also plays a central role in partitioning phenotypic variability. These analyses of contemporary factors coupled with analyses of morphological variability holds promise for addressing the functional roles of mussel height and width and what proportion of phenotypic variability can be attributed to environmental factors
The Primarily Undergraduate Nanomaterials Cooperative: A New Model for Supporting Collaborative Research at Small Institutions on a National Scale
The Primarily Undergraduate Nanomaterials Cooperative (PUNC) is an organization for research-active faculty studying nanomaterials at Primarily Undergraduate Institutions (PUIs), where undergraduate teaching and research go hand-in-hand. In this perspective, we outline the differences in maintaining an active research group at a PUI compared to an R1 institution. We also discuss the work of PUNC, which focuses on community building, instrument sharing, and facilitating new collaborations. Currently consisting of 37 members from across the United States, PUNC has created an online community consisting of its Web site (nanocooperative.org), a weekly online summer group meeting program for faculty and students, and a Discord server for informal conversations. Additionally, in-person symposia at ACS conferences and PUNC-specific conferences are planned for the future. It is our hope that in the years to come PUNC will be seen as a model organization for community building and research support at primarily undergraduate institutions
Formation of Zn- and Fe-sulfides near hydrothermal vents at the Eastern Lau Spreading Center: implications for sulfide bioavailability to chemoautotrophs
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Lipophilic G-Quadruplexes Are Self-Assembled Ion Pair Receptors, and the Bound Anion Modulates the Kinetic Stability of These Complexes
Marine Chemical Technology and Sensors for Marine Waters: Potentials and Limits
A significant need exists for in situ sensors that can measure chemical species involved in the major processes of primary production (photosynthesis and chemosynthesis) and respiration. Some key chemical species are O-2, nutrients (N and P), micronutrients (metals), pCO(2), dissolved inorganic carbon (DIC) pH, and sulfide. Sensors need to have excellent detection limits, precision, selectivity, response time, a large dynamic concentration range, low power consumption, robustness, and less variation of instrument response with temperature and pressure, as well as be free from fouling problems (biological, physical, and chemical). Here we review the principles of operation of most sensors used in marine waters. We also show that some sensors can be used in several different oceanic environments to detect the target chemical species, whereas others are useful in only, one environment because of various limitations. Several sensors can be used truly in situ, whereas many others involve water brought into a flow cell via tubing to the analyzer in the environment or aboard ship. Multi-element sensors that measure many chemical species in the same water miss should be targeted for further development
Long-Term Temporal Variability in Hydrogen Peroxide Concentrations in Wilmington, North Carolina USA Rainwater
Measurements of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), pH, dissolved organic carbon (DOC), and inorganic anions (chloride, nitrate, and sulfate) in rainwater were conducted on an event basis at a single site in Wilmington, NC for the past decade in a study that included over 600 individual rain events. Annual volume weighted average (VWA) H<sub>2</sub>O<sub>2</sub> concentrations were negatively correlated (<i>p</i> < 0.001) with annual VWA nonseasalt sulfate (NSS) concentrations in low pH (<5) rainwater. Under these conditions H<sub>2</sub>O<sub>2</sub> is the primary aqueous-phase oxidant of SO<sub>2</sub> in the atmosphere. We attribute the increase of H<sub>2</sub>O<sub>2</sub> to decreasing SO<sub>2</sub> emissions which has had the effect of reducing a major tropospheric sink for H<sub>2</sub>O<sub>2</sub>. Annual VWA H<sub>2</sub>O<sub>2</sub> concentrations in low pH (<5) rains showed a significant increase over the time scale of this study, which represents the only long-term continuous data set of H<sub>2</sub>O<sub>2</sub> concentrations in wet deposition at a single location. This compositional change has important implications because H<sub>2</sub>O<sub>2</sub> is a source of highly reactive free radicals so its increase reflects a higher overall oxidation capacity of atmospheric waters. Also, because rainwater is an important mechanism by which H<sub>2</sub>O<sub>2</sub> is transported from the atmosphere to surface waters, greater wet deposition of H<sub>2</sub>O<sub>2</sub> could influence the redox chemistry of receiving watersheds which typically have concentrations 2–3 orders of magnitude lower than rainwater
ASV-labile Znin filtered vent fluid samples collected from the ELSC and in filtered samples amended with 0
5 μM Cu(II) prior to analysis for ASV-labile Zn.<p><b>Copyright information:</b></p><p>Taken from "Formation of Zn- and Fe-sulfides near hydrothermal vents at the Eastern Lau Spreading Center: implications for sulfide bioavailability to chemoautotrophs"</p><p>http://www.geochemicaltransactions.com/content/9/1/6</p><p>Geochemical Transactions 2008;9():6-6.</p><p>Published online 19 May 2008</p><p>PMCID:PMC2396607.</p><p></p
Zn concentration as determined by anodic stripping voltammetry in model Zn-sulfide solutions containing 2 μM ZnS, 2 μM ZnS 2
5 μM cysteine (CYS), and 2 μM Zn + 2.5 μM CYS (all model solutions prepared in 0.1 M KCl, 4 mM HEPES buffer, pH 7.6). (a) ASV-labile Zn in unfiltered solutions before and after addition of 0.5 μM Cu(II). Addition of Cu(II) caused oxidative dissolution of ZnS; (b) ASV-labile and total Zn quantified in filtered (< 0.2 μm) solutions.<p><b>Copyright information:</b></p><p>Taken from "Formation of Zn- and Fe-sulfides near hydrothermal vents at the Eastern Lau Spreading Center: implications for sulfide bioavailability to chemoautotrophs"</p><p>http://www.geochemicaltransactions.com/content/9/1/6</p><p>Geochemical Transactions 2008;9():6-6.</p><p>Published online 19 May 2008</p><p>PMCID:PMC2396607.</p><p></p