Scanning electron microscopy of the scales of Cyprinus carpio, inhabiting two government-sponsored fish farms, with different sources of pollutants, in the North-East state of Meghalaya, India revealed extensive damage to them. Lepidonts, which are teeth-like structures present on the edge of circulii, were discovered to be either partly or completely damaged. The dislodgment of complete rows of lepidonts along with broken lepidonts was also observed. Loss of symmetry and torn areas of circulii are some of the abnormalities also observed as compared to control samples. The alterations observed could be because of the high sensitivity of the scales to environmental stress and their capacity to react to low concentrations of pollutants, which makes them a sensitive bioindicator of water pollution. The study hence not only represents an advance in pollution research, by employing a highly sophisticated analytical approach to reveal the above-mentioned microstructural scale abnormalities, but it can also have scientific impact on the society at large and the fish culturist in particular in understanding the destructive impact of pollution caused by mismanagement of city garbage and agricultural effluents.

Gilding threads collected from Spanish and Portuguese palaces and from the embroideries and adornments of sculptures of the Virgin and Christ that form part of Sevillian Holy Week were analyzed and compared (20 artifacts were evaluated). The study covered a broad time period with examples from the 13th to 14th centuries, 18th to 20th centuries, and also including modern embroideries. A combination of scanning electron microscopy and energy-dispersive X-ray spectroscopy was used. The knowledge of the layered structures of the threads has provided very valuable information regarding the manufacturing techniques. The different metal threads found in the embroidery studied consisted of gold, silver, copper, and alloys of these metals and aluminium. The fabrication procedures often differed in the different workshops and changed with time. In the modern embroideries, a decrease of precious metal concentration was detected. The threads were wound around a core of silk threads.

Previous studies have shown the anthelmintic efficacy of Senna alata, Senna alexandrina and Senna occidentalis on the zoonotic parasite Hymenolepis diminuta through microscopic studies on morphological structure. The present study is based on the light and confocal microscopic studies to understand if Senna extracts affect neurotransmitter activity of the parasites. A standard concentration (40 mg/mL) of the three leaf extracts and one set of 0.005 mg/mL concentration of the reference drug praziquantel were tested against the parasites, keeping another set of parasites in phosphate buffer saline as a control. Histochemical studies were carried out using acetylthiocholine iodide as the substrate and acetylcholinesterase as the marker enzyme for studying the expression of the neurotransmitter of the parasite and the staining intensity was observed under a light microscope. Immunohistochemical studies were carried out using anti serotonin primary antibody and fluorescence tagged secondary antibody and observed using confocal microscopy. Intensity of the stain decreases in treated parasites compared with the control which implies loss of activity of the neurotransmitters. These observations indicated that Senna have a strong anthelmintic effect on the parasite model and thus pose as a potential anthelmintic therapy.

This paper deals with the study of the surface morphology of barbels, upper lips, and adhesive discs in four hill stream fish species collected from Basistha River, a torrential river in Guwahati city, Assam, India. The four species belonging to the genus Garra namely, Garra gotyla (Gray, 1830), Garra gravelyi (Annandale, 1919), Garra stenorhynchus (Jerdon, 1849), and Garra nasuta (McClelland, 1838) were collected from the same torrential habitat. These fish revealed anatomical peculiarities in their barbels, lips, and adhesive discs which are believed to help them in adapting to such habitats. Organs exhibiting adaptive modifications (barbels, lips, and adhesive discs) were studied with the scanning electron microscope. The study primarily revealed the presence of type I and type II taste buds in the barbels, lips, and adhesive discs, and numerous unculi surrounded by microridges in the upper lips and adhesive discs. A cumulative, intercalated action of these organs enables these fish to adhere and adapt to rocky, torrential streams. Special ability to adapt to these habitats was reflected from the two types of taste buds (I and II) present in the barbels, and the clustering of excrescencies bearing unculi in the lips and adhesive discs of the fish.

On the basis of optical microscopy, scanning electron microscopy with energy-dispersive spectrometry and X-ray powder diffraction analyses, we present detailed mineralogical and petrographical characteristics of 63 samples of cooking and tablewares, which originate from two Medieval horizons (S1 and S2) in the Studenica Monastery, as well as of three samples of clays regarded as possible pottery raw material. The composition of the ceramic matrix is compatible with the composition of local clay and clasts that reflect the geology of the Studenica’s surroundings. This indicates that almost all studied vessels are unequivocally made locally. However, four wares may represent imports because they show similarities with Byzantine sgraffito wares, and ceramics from the Peloponnese (13th century). In terms of technological and morphological characteristics, the studied pottery collection represents a standardized production. Firing temperatures, estimated according to the level of matrix crystallinity, mineral reactions, and the mode of the appearance of fracture surfaces, indicate that most of cooking wares were fired at 600–700°C. All glazed wares, including tablewares and cooking pots from both S1 and S2, were fired at minimum 800–900°C. Along with technological and morphological standardization the characteristics of the studied collection show knowledge of traditional skills as well as trends within the Byzantine artistic craft circle.

Using the recently developed techniques of electron tomography, we have explored the first stages of disfiguring formation of zinc soaps in modern oil paintings. The formation of complexes of zinc ions with fatty acids in paint layers is a major threat to the stability and appearance of many late 19th and early 20th century oil paintings. Moreover, the occurrence of zinc soaps in oil paintings leading to defects is disturbingly common, but the chemical reactions and migration mechanisms leading to large zinc soap aggregates or zones remain poorly understood. State-of-the-art scanning (SEM) and transmission (TEM) electron microscopy techniques, primarily developed for biological specimens, have enabled us to visualize the earliest stages of crystalline zinc soap growth in a reconstructed zinc white (ZnO) oil paint sample. In situ sectioning techniques and sequential imaging within the SEM allowed three-dimensional tomographic reconstruction of sample morphology. Improvements in the detection and discrimination of backscattered electrons enabled us to identify local precipitation processes with small atomic number contrast. The SEM images were correlated to low-dose and high-sensitivity TEM images, with high-resolution tomography providing unprecedented insight into the structure of nucleating zinc soaps at the molecular level. The correlative approach applied here to study phase separation, and crystallization processes specific to a problem in art conservation creates possibilities for visualization of phase formation in a wide range of soft materials.

In this study, we sought to evaluate the influence of cigarette smoke and pH cycling on the chemical composition and surface/cross-sectional enamel microhardness. A total of 40 dental blocks obtained from bovine incisors were divided into four groups (n=10): no treatment (control); exposure to cigarette smoke (CS); exposure to pH cycling (PC); and exposure to cigarette smoke and pH cycling (CS-PC). The samples were analyzed by synchrotron radiation micro X-ray fluorescence, bench mode X-ray fluorescence, as well as surface microhardness (SMH) and cross-sectional microhardness (CSMH) testing. The SMH results were submitted to analysis of variance (ANOVA) and Tukey’s test. The CSMH results were evaluated using split-plot ANOVA and Tukey’s test. A high amount of Cd and Pb and traces of Ni and As were observed in enamel and dentin after exposure to cigarette smoke (CS and CS-PC). The SMH and CSMH of CS were statistically higher when compared with the control. The PC and CS-PC showed lower SMH and CSMH. We conclude that exposure to cigarette smoke promoted heavy metal deposition in enamel/dentin. In addition, it increased the enamel microhardness but did not promote a protective effect on the in vitro development of caries. The clinical significance of this work is that there is significant bioaccumulation of heavy metals from cigarette smoke on the surface and in the enamel and dentin.