Size-strain line-broadening analysis of anatase/brookite (TiO)-based nanocomposites with carbon (C): XRPD and Raman spectroscopic analysis.

A size-strain line-broadening analysis of the XRPD patterns and Raman spectra for two anatase/brookite (TiO)-based nanocomposites with carbon (C) was carried out and the results compared with those of a similar sample free of carbon. The crystal structures and microstructures of anatase and brookite, as well as their relative abundance ratio, have been refined from XRPD data by the Rietveld method (the low amount of carbon is neglected). The XRPD size-strain analysis resulted in reliable structure and microstructure results for both anatase and brookite.

Synergy of interference, scattering and pigmentation for structural coloration of moth.

Structural and pigment colorations are omnipresent in insects, producing a range of colors for camouflage, warning, mimicry and other strategies necessary for survival. Structural coloration has attracted a lot of attention due to its significance in biophotonics, biomimetics and even esthetic appeal. The coupling of structural and pigment colorations has been largely unnoticed.

Thermal radiation management by natural photonic structures: Morimus asper funereus case.

Convective, conductive and radiative mechanisms of thermal management are extremely important for life. Photonic structures, used to detect infrared radiation (IR) and enhance radiative energy exchange, were observed in a number of organisms. Here we report on sophisticated radiative mechanisms used by Morimus asper funereus, a longicorn beetle whose elytra possess a suitably aligned array of lenslets and blackbodies.

Chemistry and morphology of the pygidial glands in four Pterostichini ground beetle taxa (Coleoptera: Carabidae: Pterostichinae).

Morphology of the pygidial glands and chemical composition of their secretions in adults of four ground beetle representatives of the Pterostichini tribe (Coleoptera: Carabidae) were analysed. Molops (Stenochoromus) montenegrinus, Pterostichus (Cophosus) cylindricus, P. (Feronidius) melas and P.

A new troglobitic species of the genus Leptomeson Jeannel, 1924 (Coleoptera: Leiodidae: Cholevinae: Leptodirini) from the Island of Šolta (middle Dalmatia, Croatia).

Leptomeson Jeannel, 1924, originally treated as a subgenus of Anthroherpon Reitter, 1889 (Jeannel, 1924), was erected to a distinct genus by Guéorguiev (1990). It currently includes 13 endemic taxa (nine species and four subspecies) (Perreau, 2015), of which five species are recently described (Giachino et al., 2011).

Naturally safe: Cellular noise for document security.

Modern document protection relies on the simultaneous combination of many optical features with micron and submicron structures, whose complexity is the main obstacle for unauthorized copying. In that sense, documents are best protected by the diffractive optical elements generated lithographically and mass-produced by embossing. The problem is that the resulting security elements are identical, facilitating mass-production of both original and counterfeited documents.

Photonic structures improve radiative heat exchange of Rosalia alpina (Coleoptera: Cerambycidae).

The insect cuticle serves a multitude of purposes, including: mechanical and thermal protection, water-repelling, acoustic signal absorption and coloration. The influence of cuticular structures on infrared radiation exchange and thermal balance is still largely unexplored. Here we report on the micro- and nanostructured setae covering the elytra of the longicorn beetle Rosalia alpina (Linnaeus, 1758) (Coleoptera: Cerambycidae) that help the insect to survive in hot, summer environments.

Graphene oxide improves the biocompatibility of collagen membranes in an in vitro model of human primary gingival fibroblasts.

Commercial collagen membranes are used in oral surgical procedures as scaffolds for bone deposition in guided bone regeneration. Here, we have enriched them with graphene oxide (GO) via a simple non-covalent functionalization, exploiting the capacity of oxygenated carbon functional moieties of GO to interact through hydrogen bonding with collagen. In the present paper, the GO-coated membranes have been characterized in terms of stability, nano-roughness, biocompatibility and induction of inflammatory response in human primary gingival fibroblast cells.

Scattering-enhanced absorption and interference produce a golden wing color of the burnished brass moth, Diachrysia chrysitis.

Here we report how interference and scattering-enhanced absorption act together to produce the golden wing patches of the burnished brass moth. The key mechanism is scattering on rough internal surfaces of the wing scales, accompanied by a large increase of absorption in the UV-blue spectral range. Unscattered light interferes and efficiently reflects from the multilayer composed of the scales and the wing membranes.

Nonlinear microscopy of chitin and chitinous structures: a case study of two cave-dwelling insects.

We performed a study of the nonlinear optical properties of chemically purified chitin and insect cuticle using two-photon excited autofluorescence (TPEF) and second-harmonic generation (SHG) microscopy. Excitation spectrum, fluorescence time, polarization sensitivity, and bleaching speed were measured. We have found that the maximum autofluorescence signal requires an excitation wavelength below 850 nm.