ALBERT

Description: A new compound, jolynamine (1), was isolated from the marine brown alga Jolyna laminarioides collected from the coast of Karachi, Pakistan. In addition, four known compounds, namely saringosterol (2), loliolide (3), methyl-4-hydroxybenzoate (4) and propyl-4-hydroxybenzoate (5), were isolated for the first time from the marine brown alga Iyengaria stellata, and two known compounds, namely 3,4,5-trimethylaniline (6) and harmine (7), were isolated for the first time from the marine brown alga Melanothamnus afaqhusainii. Compound 6 is synthetically known but was isolated for the first time from a natural source. The structures of these compounds were elucidated with the help of powerful spectroscopic techniques. Furthermore, the methanolic extracts of both algae showed anti-microbial activities against various bacteria and fungi.

Description: Introduction: Nanocarriers are considered to be one of the most innovative drug delivery systems, owing to their high potential in drug protection, delivery and targeting to the diseased site. Unfortunately, their applicability is hampered mainly by their uptake, due to macrophagic recognition and lack of specificity, if not properly engineered. Areas covered: Sialic acid (SA) and its derivatives have recently been studied in order to govern their stealthness as carriers and their effectiveness as targeting moieties. In this review, the most outstanding research (in vitro and in vivo) dealing with the use of SA or its derivatives to modify the surface carriers, in order to achieve targeted or stealth nanosystems, is summarized. Moreover, the application of SA or its derivatives as modifiers in cancer targeting and therapy, and in recognition purposes, is considered. Expert opinion: The application of SA-based strategies for nanocarrier engineering represents one of the most stimulating challenges in drug delivery and drug targeting. Both in vivo and in vitro results on stealth or targeted nanocarriers, modified with different kinds of SA or SA derivative, have highlighted the great potential of this approach. These studies have drawn attention to both the advantages (stealth properties, targeting ability, cancer inhibition, viral and inflammation recognition, brain targeting) and the possible disadvantages (i.e., presence of possible multi-target side effect outputs) of this strategy, and overall suggests that further investigations on this strategy are required.

Description: The abundance of gold in crustal rocks is an important constraint on the formation of gold deposits. Gold concentrations in unmineralised igneous, sedimentary and metamorphic rocks range from 0.05 to 20 ppb with average concentrations commonly between 0.5 and 5 ppb. Analytical methods with ultra-low detection limits are required to observe the full range of concentrations. Gold concentrations in igneous rocks are strongly controlled by the behaviour of sulphur. Higher gold concentrations occur in sulphur-undersaturated rocks compared to sulphur saturated igneous rocks. Mid ocean ridge basalt has lower gold concentration than ocean-island and volcanic-arc basalt, due mainly to lower oxygen fugacity at MOR settings that causes sulphur saturation. Gold concentrations in sedimentary rocks increase with increasing abundance of diagenetic sulphide minerals and organic matter. Gold concentrations in metamorphic rocks decrease systematically with increasing metamorphic grade. Amphibolite facies rocks commonly contain between 50 and 80% less gold than their unmetamorphosed protolith rocks.

Description: In this article, wave refraction and shoaling in coastal areas were investigated and used to derive the bathymetry. With its high spatial resolution, which can achieve up to 1 m in SpotLight mode, and its low cut-off wavelength, the TerraSAR-X satellite provides images that are particularly suitable for the observation of wave behaviour in transient and shallow waters. By computing the two-dimensional (2D) spectra, shoaling waves were tracked from the open sea to the shoreline. The observed wave refraction and shoaling were compared with wave refraction laws and first-order wave theory (Airy theory). The retrieved bathymetry was compared against depth data from other sources such as ETOPO1, the US Coastal Relief Model and sea charts from the British Admiralty. A further aim of this article was the investigation of breaking waves showing up as near-shore image patterns. A theory is presented of how to derive the height of breaking waves by use of this pattern. Synthetic aperture radar (SAR) images with azimuth as well as range travelling waves were investigated. As test sites, we chose the entrance of Port Phillip near Melbourne (Australia) and the Duck Research Pier in North Carolina (USA).

Description: The temporal and spatial variability of sea-ice radar signatures in the Southern Ocean during late winter, spring and early summer from QuikSCAT data is presented. We observe a circumpolar and broad band of sea-ice close to the marginal ice zone that is characterized by very high radar backscatter. This feature is explained through detailed in situ observations of snow and sea-ice properties as well as in relation to meteorological conditions, which were derived from US National Center for Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR) reanalysis data. Our results indicate that high backscatter regions are caused by metamorphous snow, which forms through re-freezing after short-term melt events. This process is connected with the episodic passes of low-pressure systems entraining warmer air from the north. South of the Antarctic Circumpolar Trough, sea-ice is not affected by this influence and shows spatially homogenous microwave signatures with low backscatter.

Description: 18.10. - 25.10.2011

Description: Dates of Cruise: 13. September to 19. September 2011 Projects: Student course in physical oceanography. Areas of Research: Physical oceanography Port call: Kiel – Warnemünde – Kiel

Description: The mussel Mytilus galloprovincialis is a common aquaculture species, and also a major fouling organism that has negative economic impacts. There are no standard assay conditions for this important species and therefore, this study quantified the effect of key factors on the settlement of pediveligers and plantigrades. Density dependent settlement did not occur for either pediveligers or plantigrades. Settlement increased in drop assays in a 12 h light:12 h dark cycle, while bottom shade had no effect of any magnitude. In addition, settlement was significantly enhanced by storing pediveligers for between 4 and 24 days at 4 °C. Overall, these data provide the template to optimise and standardise static laboratory settlement assays for mussels in order to develop materials that either enhance settlement for the aquaculture industry, or deter settlement for antifouling applications. Furthermore, simple mechanisms such as storage at 4 °C can enhance settlement beyond current methods used in aquaculture hatcheries.