Potential for identification of wild night-flying moths by remote infrared microscopy

There are hundreds of thousands of moth species with crucial ecological roles that are often obscured by their nocturnal lifestyles. The pigmentation and appearance of moths are dominated by cryptic diffuse shades of brown. In this study, 82 specimens representing 26 moth species were analysed using infrared polarimetric hyperspectral imaging in the range of 0.95–2.5 µm. Contrary to previous studies, we demonstrate that since infrared light does not resolve the surface roughness, wings appear glossy and specular at longer wavelengths. Such properties provide unique reflectance spectra between species. The reflectance of the majority of our species could be explained by comprehensive models, and a complete parametrization of the spectral, polarimetric and angular optical properties was reduced to just 11 parameters with physical units. These parameters are complementary and, compared with the within-species variation, were significantly distinct between species. Counterintuitively to the aperture-limited resolution criterion, we could deduce microscopic features along the surface from their infrared properties. These features were confirmed by electron microscopy. Finally, we show how our findings could greatly enhance opportunities for remote identification of free-flying moth species, and we hypothesize that such flat specular wing targets could be expected to be sensed over considerable distances.     

Phosphine functionalized polyaniline nanostructures

We study the problem of limited functionalization options for polyaniline through the surface attachment of phosphine coupling reagents. These studied linkers are P(CH₂OH)₃ and Ph₂PCH₂OH, and are attached to both conventional and nanostructured polyaniline. Additionally, model compounds are considered, extending the scope of our analysis. The successful attachment results indicate the potential for further functionalization, using the hydroxymethyl terminal groups of the phosphines for primary and secondary amine chemistry. These results should enable the development of sensitive and molecule-specific polyaniline-based devices.     

Transparent exopolymeric particles' distribution in the northern Adriatic and their relation to microphytoplankton biomass and composition

Transparent exopolymer particles (TEP) are generated during transformation processes within the non-living organic matter continuum in the seawater. Seasonal dynamics of TEP along the Po River Delta-Rovinj transect was followed during the 3-year period, using a spectrophotometric method of determination of TEP. Relationships between TEP and phytoplankton biomass (chlorophyll a), abundance and composition, as well as phaeophytin, were analysed. Microphytoplankton spring blooms are confirmed to be an important source of TEP, with some species more related to TEP concentration dynamics, such as Chaetoceros sp. and Skeletonema costatum. Notable spatial west to east gradient of autotrophic biomass and consequently of TEP was observed, as well as gradual decrease with depth. In addition, TEP concentration increments were observed up to 2 months before the mucilage events followed by the decrease of TEP concentration during the event itself. Pattern of TEP dynamics in the years with mucilage events was the most pronounced in 2002, when the event was spatially and temporally the most extended.     

The effect of photo-irradiation on the optical properties of thiol-capped CdTe quantum dots

In this report, the effect of photo-irradiation on the optical properties of thioglycolic acid (TGA) capped CdTe QDs was investigated. The photo-irradiation led to an increase in the photoluminescence (PL) efficiency of TGA-capped CdTe QDs with a low quantum yield under both the open air and nitrogen atmosphere. The photo-irradiation caused a blue-shift of PL peak under the open air and almost no change of PL peak position under the nitrogen atmosphere. The XPS study revealed the oxidation of the unpassivated surface of the Te atoms which mainly contributed to the observed optical property changes for CdTe QDs photo-irradiated under the open air. While for the CdTe QDs photo-irradiated under the nitrogen atmosphere, the decomposition of TGA led to the release of sulphur which formed a CdS shell on the CdTe core, resulting in an enhanced PL efficiency.     

Co-occurrence of ochratoxin A and citrinin in unprocessed cereals established during a three-year investigation period

The aim of this study was to investigate ochratoxin A (OTA) and citrinin (CIT) co-occurrence in different unprocessed cereals (n = 189) originating from Croatia during a three-year investigation period (2014–2016) using validated enzyme immunoassay (ELISA) methods. CIT and OTA were determined in 49% and 7% of samples, respectively. Significantly higher (p < 0.05) overall mean concentrations were determined for CIT (66.8 ± 76.0 µg/kg) in comparison to OTA (5.2 ± 1.1 µg/kg). Based on the analysis of all investigated cereals, CIT was found about 15 times more frequently than OTA and in similarly (15-fold) higher concentrations, irrespective of the cultivation year. The results revealed a moderately positive correlation between OTA and CIT concentrations in maize (r_s = 0.44) and wheat (r_s = 0.59), whereas in barley and oat this correlation (p > 0.01) was not significant.     

Self‐assembled centimetre‐sized rods obtained in the oxidation of o‐phenylenediamine and aniline

Morphologically well‐defined rods of approximately 1 cm in length are effectively and economically obtained by mixing ortho‐phenylenediamine (30 mmol L^?1) with ammonium persulfate (12.5 mmol L^?1) in an acidic solution (0.37 mol L^?1 HCl) at room temperature with and without the presence of 50 mmol L^?1 aniline. These self‐assembled, morphologically uniform products can be potentially scaled up and used as morphological templates to fabricate well‐defined structures of other materials such as conducting polymers. The products were characterized using Raman, UV‐visible, high‐resolution NMR (¹H and ¹³C) and mass spectroscopies, X‐ray diffraction, scanning electron microscopy and elemental analysis. Apart from certain differences in visual appearance and in X‐ray diffractograms, other analytical data suggest that there are no structural changes upon addition of aniline into the reaction mixture. NMR and mass spectra imply that all syntheses carried out either with or without aniline result in a mixture of two products, attributed to 2,3‐phenazinediamine and 3‐aminophenazin‐2‐ol. A formation mechanism based on hydrogen bonding and π–π stacking has been proposed. © 2015 Society of Chemical Industry     

Composition and seasonal variation of fatty acids of <Emphasis Type="Italic">Diplodus vulgaris</Emphasis> L. from the Adriatic Sea

Muscle tissue from the common two-banded sea bream Diplodus vulgaris L. originating from the Adriatic Sea, Croatia, was analyzed. The FA composition of neutral (TAG) and polar (PE, PC, PI/PS) lipid classes was determined, as well as the lipid and water contents during winter and summer periods. Both the total lipid and water contents were higher in the winter period. We identified 16 different FA. The major constituents of the total FA in both seasons were saturates: palmitic (16∶0) and stearic acids (18∶0); monoenes: oleic (18∶1n−9) and palmitoleic acids (16∶1n−7); and polyunsaturates: arachidonic acid (20∶4n−6), EPA (20∶5n−3), and DHA (22∶6n−3), but their amounts and ratios differed significantly between the two seasons and between lipid fractions. The FA composition showed a noticeable pattern of seasonality that reflected fluctuations mainly in TAG. The diminution of the monounsaturated FA content in the summer was clearly followed by an increase in PUFA content. Diplodus vulgaris is a good source of natural n−3 PUFA and would therefore be suitable for inclusion in highly unsaturated low-fat diets.     

The actuation behavior and stability of p‐toluene sulfonate doped polypyrrole films formed at different deposition current densities

Free‐standing films of polypyrrole doped with p‐toluene sulfonate (PPy/pTS) were electropolymerized galvanostatically at different deposition current densities and their electrochemomechanical deformation (ECMD) properties were measured in situ during cyclic voltammetry experiments. It was found that films exhibiting a higher cation‐driven actuation strain were generated when a lower current density was used in electropolymerization, which also led to an increase in PPy conductivity and doping level. A decrease in cation‐driven strain with time was observed in all cases due to a loss of pTS anions from the films. Raman, FTIR, and elemental analyses were used to characterize the films grown at different deposition current densities and no sign of excessive overoxidation was found. SEM images revealed that the morphology of the films was affected by the current density during electropolymerization. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009