Floating marine litter as a raft for drifting voyages for Planes minutus (Crustacea: Decapoda: Grapsidae) and Liocarcinus navigator (Crustacea: Decapoda: Polybiidae).

The Columbus crab Planes minutus and Arch-fronted swimming crab Liocarcinus navigator, within their distribution ranges in the Mediterranean, were found rafted on plastic macro-litter floating on the open south Adriatic. While P. minutus was recorded from inanimate flotsam outside of the Mediterranean, L. navigator is herein reported for the first time on floating marine litter. The role of floating litter as habitat or as a dispersal agent for marine invertebrates has received quite attention however, records of decapod crabs drifting on litter has been relatively sparse. Our results suggests that vast quantities of floating debris, comprised primarily of non-biodegradable plastic polymers, probably will augment natural floating substrates in the marine environment, potentially facilitating the spread of invasive species. The dispersion of rafting crabs through floating debris should be investigated given the high potential ecological risk of invasion by exotic species due to the increase in waste production (ecological risk assessment).

Quantitative multiplexed simulated-cell identification by SERS in microfluidic devices.

A reliable identification of cells on the basis of their surface markers is of great interest for diagnostic and therapeutic applications. We present a multiplexed labeling and detection strategy that is applied to four microparticle populations, each mimicking cellular or bacterial samples with varying surface concentrations of up to four epitopes, using four distinct biotags that are meant to be used in conjunction with surface enhanced Raman spectroscopy (SERS) instead of fluorescence, together with microfluidics. Four populations of 6 µm polystyrene beads were incubated with different mixtures, "cocktails" of four SERS biotags (SBTs), simulating the approach that one would follow when seeking to identify multiple biomarkers encountered in biological applications. Populations were flowed in a microfluidic flow-focusing device and the SERS signal from individual beads was acquired during continuous flow. The spectrally rich SERS spectra enabled us to separate confidently the populations by utilizing principal component analysis (PCA). Also, using classical least squares (CLS), we were able to calculate the contributions of each SBT to the overall signal in each of the populations, and showed that the relative SBT contributions are consistent with the nominal percentage of each marker originally designed into that bead population, by functionalizing it with a given SBT cocktail. Our results demonstrate the multiplexing capability of SBTs in potential applications such as immunophenotyping.

Diet and feeding strategy of thornback ray Raja clavata.

The diet and feeding strategy of thornback ray Raja clavata, from the eastern-central Adriatic Sea, were investigated. Stomach contents of 428 specimens, total length (L(T)) of 14·0-75·1 cm, were collected from commercial bottom trawls. The prey items identified in the stomachs belong to eight major groups: Cephalopoda, Polychaeta, Stomatopoda, Decapoda (Natantia and Reptantia), Mysidacea, Isopoda, Amphipoda and Teleostei. Decapods were the most important prey (index of relative important, %I(RI) ,= 72·8) followed by teleosts (%I(RI) = 20·4), whereas other prey groups were only occasionally ingested. Small-sized individuals (<25 cm L(T)) fed primarily on small crustaceans (mysids and amphipods), whereas large-sized specimens consumed larger prey, such as decapods, cephalopods and teleosts. Diet composition showed little seasonal variation; decapods were the most important prey in all seasons. There was high dietary similarity between sampling locations. The percentage of empty stomachs did not differ significantly among size classes and seasons. In terms of composition by species, the diet of R. clavata was characterized by a variety of rare or unimportant prey. As a result, R. clavata could be considered a generalist predator.

Biocompatibility and wettability of crystalline SiC and Si surfaces.

Crystalline silicon carbide (SiC) and silicon (Si) biocompatibility was evaluated by directly culturing three mammalian cell lines on these semiconducting substrates. Cell proliferation and adhesion quality were studied using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assays and fluorescent microscopy. The reported results show that SiC is indeed a more biocompatible substrate than Si. The surface wettability of SiC and Si samples was evaluated through static contact angle measurements, which provided interesting information regarding the influence of different cleaning procedures on the SiC surfaces. The cell proliferation data are discussed in light of the contact angle measurements results. This joint analysis leads to interesting conclusions that may help to uncover the main factors that define a semiconductor's biocompatibility.