This article presents a detailed study of the microstructure of Iberian expanded clay lightweight aggregates (LWA). Other than more commonly used mercury porosimetry (MP) and water absorption methods, the experimental study involves optical microscopy, scanning electron microscopy (SEM), and microtomography (μ-CT). Pore connectivity and how it is deployed are shown to some degree, and the pore size spectrum is estimated. LWA are in general characterized by a dense outer shell up to 200 μm thick, encasing an inner cellular structure of 10–100 times bigger pore size. Aggregate pore sizes may span from some hundreds of nanometers up to over 1 mm, though the range of 1–25 μm is more typical. A noteworthy fraction of these pores is closed, and they are mainly up to 1 μm. It is also shown that macropore spatial arrangement is affected by the manufacturing process. A step forward is given to understanding how the outer shell and the inner pore network influence the mechanical and physical LWA properties, particularly the density and water absorption. The joint consideration of μ-CT and SEM seems to be the most appropriate methodology to study LWA microstructure. MP analysis is likely to distort LWA pore spectrum assessment.

Confocal Raman Microscopy. Thomas Dieing, Olaf Hollricher, and Jan Toporski (Eds.). Springer, New York, 2011, 289 pages. ISBN 978-3642125218

Raman microscopy is the combination of Raman spectroscopy with optical light microscopy and was first presented in the mid-1970s. It combines the advantages of vibrational Raman spectroscopy as a noninvasive technique providing a wealth of chemical information on the properties of molecules and solids with the imaging capabilities and small sample volume requirements of an optical microscope. “Seeing is believing”: Raman microscopy can visualize the inherent chemical inhomogeneity of a sample without the need of external labels, information that cannot be obtained from simply looking at an unstained sample in the standard optical microscope. During the last decade, confocal Raman microscopy has gone through a rapid development with respect to instrumentation and software as well as the diversity of applications.

The self-assembly of α,ω-dihexylsexithiophene molecules on an Au(111) surface was examined by using scanning tunneling microscopy at room temperature, revealing the internal molecular structures of the sexithiophene backbones and the hexyl side chains. The α,ω-dihexylsexithiophene formed a large and well-ordered monolayer in which the molecule lay flatly on the Au(111) surface and was separated into two chiral domains. A detailed observation reveals that the admolecules were packed in one lamellae with their molecular axis aligned along the main axis of the Au(111) substrate with their hexyl chains deviated from ⟨110⟩ direction of the Au(111) substrate by 12 ± 0.5°. In contrast to the behavior in the three-dimensional bulk structure, flat-lying adsorption introduced molecular chirality: right- and left-handed molecules separate into domains of two different orientations, which are mirror symmetric with respect to the ⟨121⟩ direction of the Au(111) substrate. Details of the adlayer structure and the chiral self-assembly were discussed here.

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus responsible for painful disabling polyarthritis, undergoing re-emergence in the Indian Ocean and the Asian continent. Travelling and changing patterns of vector distribution, and abundance due to climate changes, make CHIKV a global threat without effective control strategies. One approach to reduce the CHIKV burden is the development of a vaccine. Virus-like particles (VLPs) are a safe and highly effective class of subunit vaccines that mimic the overall structure of virus particles. Accordingly, we aim to produce CHIKV VLPs in a baculovirus-insect cell system, well known for allowing high yields of recombinant protein expression, to be used as a vaccine preparation.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

The Anthozoa class is composed solely by marine benthic consumers, some with adaptations that enable them to inhabit even the most extreme habitats, like hydrothermal vents, the polar seas, and even whale falls. Anthozoans, such as corals and anemones, are important modulators of marine habitats in the coral reef communities, being also ecologically relevant due to their abundance and the trophic level they occupy. One of these is Actinia equina, the most conspicuous species in tidal pool communities in European shores, with a broad range of distribution from the North Sea to the Mediterranean and Aegean seas and South Africa. Histological and structural analyses allows for a more detailed biological and ecological study of these organisms, including their reproductive and metabolic behaviour. This work describes a morphologic and histologic analysis of A. equina, with these endpoints for the first time. Organisms, collected to the natural environmental were processed using a paraffin-embedding technique. Further, samples were processed following by Hematoxilin and Eosin (H & E) standard procedures with adaptations to Actiniidae conditions (the fixation time was 96 hours due to 98% of water body in these organisms). Results obtained confirm that, when compared to higher level animals, the Anthozoa are very simply organized (Figure 1). The body is built up of sheets of tissue (Figure 2 and 3), on the surface of each there is an epithelium, resting upon a middle layer of fibrous mesoglea. This generally contains no cellular elements other than some scattered amoebocytes and locally, genital cells (Figure 2). The aim of this work was to contribute to a new anatomic and histological baseline for these sea anemones family Actiniidae. In order to identify several taxonomic characteristics based on reproductive structures. The methods applied were standard to identify several structures that acid-basic groups ligands, such as phosphate of DNA, collagen and other nuclear proteins. The results obtained were the basic cnidarian structures such as tentacular and mesenteric anatomy. The reproductive structures are show in detail with septal filaments and mesenteric (Figure1). These structures is taxonomically relevant and into the own family (Actiniidae) could following the same patterns. The male and female A. equina mesenteries are different. The mainly conclusion of this study was that the male and female gonads can appear simultaneously in the same individual, or that it can have no defined sex.

The accuracy and precision of X-ray intensity measurements with a silicon drift detector (SDD) are compared with the same measurements performed on a wavelength dispersive spectrometer (WDS) for a variety of elements in a variety of materials. In cases of major (>0.10 mass fraction) and minor (>0.01 mass fraction) elements, the SDD is demonstrated to perform as well or better than the WDS. This is demonstrated both for simple cases in which the spectral peaks do not interfere (SRM-481, SRM-482, and SRM-479a), and for more difficult cases in which the spectral peaks have significant interferences (the Ba L/Ti K lines in a series of Ba/Ti glasses and minerals). We demonstrate that even in the case of significant interference high count SDD spectra are capable of accurately measuring Ti in glasses with Ba:Ti mass fraction ratios from 2.7:1 to 23.8:1. The results suggest that for many measurements wavelength spectrometry can be replaced with an SDD with improved accuracy and precision.

Since the discovery of the piezoelectric character of bone, the suitability of some piezoelectric materials have been studied for bone repair; they are thought to act like transducers converting the mechanical energy of skeletal deformation in electrical stimuli capable of controlling osteogenic growth. The mechanisms underlying this process are far from being understood and systematic studies at a local scale are required. Atomic force microscopy (AFM) is a unique way to observe phenomena at the nanoscale and liquid imaging provides a unique tool to assess biological phenomena at the nanoscale. So in this study, aiming at a better understanding of the role of piezoelectricity in the osteogenic growth, the interaction between a poled piezoelectric material, in this case poly (L-lactic) acid and an adhesion promoting protein, the fibronectin, and bone-like cells is evaluated by scanning probe microscopy and confocal laser scanning microscopy (CLSM).

We present a technique for the direct deposition of nanoporous GaN particles on Si substrates without requiring any post-growth treatment. The internal morphology of the nanoporous GaN particles deposited on Si substrates by using a simple chemical vapor deposition approach was investigated, and straight nanopores with diameters ranging between 50 and 100 nm were observed. Cathodoluminescence characterization revealed a sharp and well-defined near band-edge emission at ∼365 nm. This approach simplifies other methods used for this purpose, such as etching and corrosion techniques that can damage the semiconductor structure and modify its properties.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Following is a list of microscopy-related meetings and courses. The editors would greatly appreciate input to this list via the electronic submission form found in the MSA World-Wide Web page at www.msa.microscopy.com. We will gladly add hypertext links to the notice on the web and insert a listing of the meeting in the next issue of the Journal. Send comments and questions to Nan Yao, [email protected].

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Molybdenum disulfide/Tungsten disulphide (MoS2/WS2) is a compound very useful for its properties; it is used as lubricant, catalyst in hydrodesulfuration, in hydrogen fuel storage, etc. As part of the 2nd Joint Congress of the Portuguese and Spanish Microscopy Societies the present work reports about the different types of MoS2/WS2 nanomaterials which have been investigated by using aberration corrected STEM namely: (1) MoS2 nanotubes (2) MoS2 hexagonal nanoplates, (3) rippled or helical MoS2 nanowires, (4) Co-doped MoS2/WS2 nanowires and (5) fullerene-like WS2 nanoparticles.