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Abstract: Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures (Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature. [ABSTRACT FROM AUTHOR]

Abstract: An analyzer-based X-ray phase-contrast imaging (ABI) setup has been mounted at the Brazilian Synchrotron Light Laboratory (LNLS) for multiple imaging radiography (MIR) purposes. The algorithm employed for treating the MIR data collected at LNLS is described, and its reliability in extracting the distinct types of contrast that can be obtained with MIR is demonstrated by analyzing a test sample (thin polyamide wire). As a practical application, the possibility of studying ophthalmic tissues, corneal sequestra in this case, via MIR is investigated. [Copyright &y& Elsevier]

Abstract: Gradient single crystal fibers of GdTaO4–YbTaO4 have been grown by laser-heated pedestal growth (LHPG). The crystals of the compounds have differences in the lattice parameters of , and . The crystals obtained exhibit an optimum linear distribution of the compounds along the fiber axis and a lattice spacing gradient value of 2.91%/cm for reflection, the largest value of lattice spacing gradient reported up to this moment. The compositional and structural analysis shows that the LHPG technique and the GdTaO4–YbTaO4 system are very promising for obtaining good quality gradient crystals with large lattice parameters gradient. [Copyright &y& Elsevier]

Abstract: Crystalline lenses are transparent biological materials where the organization of the lens fibers can also be affected by changes at molecular level, and therefore the structure and morphology of the tissue can be correlated to the loss of transparency of the lens. In this work, internal structure of mammal lenses regarding the long-range ordering of the fibers are investigated by diffraction enhanced X-ray imaging (DEI) radiography. Moreover, DEI and absorption X-ray synchrotron radiographs for healthy and cataractous crystalline lenses are compared. Significant differences in healthy and cataractous crystalline lenses are observed. [Copyright &y& Elsevier]

Abstract: The key to understanding evolution lies in the elucidation of mechanisms responsible for the observed underlying patterns and in the observation of sequences that emerge from those evolutionary landmarks. The comparative development can be used to access the derivation of form and the homology versus the convergence of evolution features. Phylogenetic and biological homologies are necessary to discern the evolutionary origins of these features. This work examined the patterns of cranial formation in pre-born bat specimens as well as post-born opossum by means of microradiography and Diffraction-Enhanced Radiography (DER) techniques. A direct conversion CCD camera was used to provide micrometer spatial resolution in order to acquire highly detailed density images. This technique allows the observation of structures, in early stages of development, which were impossible to be observed with traditional techniques, such as clearing and staining. Some cranial features have been described for adults in the literature, but the detailed description of the appearance sequence of those features in these species is still unknown and obscure. Microradiography and diffraction-enhanced imaging can improve quality of morphological detail analysis and permit the identification of anatomical landmarks that are useful in comparative studies and are still unknown in both species. In this study, we access evolution features in cranial morphology of bats and marsupials using both X-ray techniques. [Copyright &y& Elsevier]

The existing methods to prepare crystals with controlled lattice parameters gradients are based on techniques that use accurate programmable temperature control and, often, a crucible. Little efforts have been made to adapt a crucibleless technique to prepare this kind of materials. Here we report on a procedure to design and grow crystals of any multinary oxide system having this property by the laser-heated pedestal growth technique. We studied the system CaMoO4–SrMoO4 with the purpose of obtaining crystals having a full solubility range. Preliminary data on composition and crystal perfection of these crystals show that they gather enough requirements for several technological applications. [Copyright &y& Elsevier]