Geomagnetic turbulence at L'Aquila (Italy): Preliminary results of a variance analysis

Summary Some preliminary measurements of the geomagnetic turbulence at L'Aquila, in the range of frequency of micropulsations, have been conducted during November 1983. The 60 s variances of the horizontal components show a clear peak around the local noon, while the vertical component is better correlated with the local index of geomagnetic activity which, in the period of interest, has peak values in the afternoon and evening hours. Real-time ?alert? algorithms select the most significant events. These events, which tend to occur in the range of frequency of Pc 2 and Pc 3, perturb mainly the horizontal components and the field fluctuations is often oriented along the averageH. This activity is supported by the Ministero della Pubblica Istruzione (40%) and by the Gruppo Italiano di Fisica Cosmica del C.N.R.     

Petrographic, biological, and chemical techniques used to characterize two tombs in the Protestant Cemetery of Rome (Italy)

In this multidisciplinary contribution, several diagnostic tests were carried out in order to characterize the stone materials, forms of alteration, and protective products applied in the past to two monumental tombs located in the Protestant Cemetery of Rome (Italy).     

R.F. (280 MHz) EPR imaging of extended samples: Apparatus and preliminary results

This paper presents the preliminary results obtained using an Electron Paramagnetic Resonance imaging apparatus operating at 280 MHz. The acquisition technique and the procedure used to obtain the spin density spatial localization are presented and specimen images of extended samples are given. The accuracy of the images and the spatial resolution are also discussed.     

Petrographic characterization and provenance determination of the white marbles used in the Roman sculptures of Forum Sempronii (Fossombrone,Marche, Italy)

The Roman municipium of Forum Sempronii (Fossombrone, Marche) was located along the ‘Via Consolare Flaminia’, in the stretch of road where it ran along the final sector of the valley of the River Metauro (Mataurus). The ancient colony of Forum Sempronii, which is cited by Strabo, Pliny, and Ptolemy, was found in the second century BC, probably on the site of an earlier community and its activity continued until the end of the fifth century AD. During ancient and more recent archaeological excavations, many fragments of coloured stones and marbles, and some white marble sculptures have been unearthed. In this paper, we report the results of the provenance identification of the white marbles used for the sculptures found in the archaeological site of Forum Sempronii and now displayed at the local archaeological museum. The determination of the source origin of the white marbles used for the sculptures has been established by mineralogical-petrographic and geochemical analyses. Microscopic study of thin sections together with carbon and oxygen stable isotope ratios indicate that more than one type of white marbles was used: Pentelikon, Lunense, and Thasian.     

Accurate determination of the Ca:P ratio in rough hydroxyapatite samples by SEM‐EDS,PIXE and RBS—a comparative study

The Ca:P ratio in a certified standard of hydroxyapatite was determined by X‐ray spectrometry (XRS), with the X‐rays excited by both electrons and ions using energy dispersive spectroscopy on the scanning electron microscope (SEM‐EDS) and particle‐induced X‐ray emission (PIXE). The certified value of Ca:P was accurately verified by 3 MeV ⁴He⁺ Rutherford Backscattering Spectrometry (RBS). We show that the demonstrably rough surface of this sample does not cause perturbation of the Ca:P ratio within the uncertainties of each of the XRS measurements. Copyright © 2009 John Wiley & Sons, Ltd.     

The study of the mural painting in the 12th century monastery of Santa Maria delle Cerrate (Puglia‐Italy): characterization of materials and techniques used

A multidisciplinary research was conducted by the University of Salento in collaboration with the Lecce Provincial Museum, in order to study different forms of art widespread in the Salento peninsula (Southern Italy) very valuable from an artistic point of view and important as driving force for the tourism of the area. In this research, the archaeometrical analysis was used to study the first cycle of paintings of the church of Santa Maria delle Cerrate, an italo‐greek monastery located in the country about 15 km north‐east of Lecce, probably built in the 12th century. Microscopic, chromatographic and spectrometric techniques were used: optical microscopy was used to study samples and the relevant stratigraphy, micro‐Raman Spectroscopy to identify pigments and Gas Chromatography with Mass Spectrometric Detection to investigate the techniques masters used to decorate the monastery church. Further information on organic and inorganic materials present in the samples were obtained from Fourier transform infrared analysis in attenuated total reflectance. Materials and techniques were clearly ascertained, and, interestingly, pigments were applied both by fresco and egg‐based tempera. Among the various pigments detected, the identification of both lapis lazuli and lead white opened new perspectives both from the historical and conservative points of view. Copyright © 2013 John Wiley & Sons, Ltd.     

Structural and magnetic study of the Ti-doped barium hexaferrite ceramic samples: Theoretical and experimental results

We present a theoretical and experimental study of the structural and magnetic properties of M-type Ti⁴⁺-doped barium hexaferrite BaFe_{(12−(4/3)x)}Ti_xO₁₉ with x=0, 0.1, 0.2, 0.3, 0.5, 0.7 and 1.3. The XRD patterns and magnetic measurements show appreciable variations in the values of the saturation magnetization and the magnetic anisotropy field, H_an, with increasing Ti⁴⁺ content. We did not observe significant changes in the Lotgering factor along the (0 0 l) direction and in the texture coefficient, C_ex, which was estimated from the torque curves. The magnetic properties of these materials are explained by the combined effect of the coherent rotation of the magnetic domains and the replacements of Fe³⁺ by Ti⁴⁺ ions in the octahedral and tetrahedral sites. The influence of the Ti⁴⁺ content on the samples was studied theoretically by using a statistical phenomenological model. The main purpose of the model is to make preliminary predictions of the distribution of any dopant cation in the Fe³⁺ sites. As a result, we are able to analyze both structural and magnetic features of M-type barium hexaferrite.     

Ultrastructural aspects of naturally occurring wound in the tunic of two ascidians: Ciona intestinalis and Styela plicata (Tunicata)

Efficient wound healing is essential for all animals from insects to mammals. Ciona intestinalis and Styela plicata are solitary ascidians belonging to urochordates, a subphylum that occupies a key phylogenetic position as it includes the closest relative to vertebrates. Urochordate first physical barrier against invaders is the tunic, an extracellular matrix that is constantly exposed to all kinds of insults. Thus, when damage occurs, an innate immune response is triggered to eliminate impaired tissue and potentially pathogenic microbes, and restore tissue functionality. Ultrastructural aspects of the tunic in the wound healing process of two ascidians are described. In the injured areas, we evidenced thinning of the tunic and areas of low fibre density, dense intratunic bacterial and protozoan population, and inflammatory aspects such as the increase in tunic cells, their aggregates, and phagocytosis. This is the first report on tunic physical wounding occurring in the natural habitat.     

Radon measurements in the SE and NE flank of Mt. Etna (Italy)

Soil Radon has been monitored at two fixed sites located in the northeastern and southeastern flank of Mt. Etna. In this study we report the comparison between in-soil Radon concentration trend recorded in the SE flank and that one recorded in the NE one, where an in-soil Radon detection system is operating since 2001.The aim of this work was to implement the investigation area finding a suitable radon detection site, in the south-east flank of Mt. Etna, in order to better understand possible links between Radon anomalies and volcano dynamic.Radon data collected in NE and SE sites were compared with the volcanic tremor, frequency of occurrence of earthquakes and seismic strain-release recorded at a fixed 3D digital seismic station placed in the NE site.Same general in-soil Radon trends and anomalies were found in both sites. These results have confirmed the suitability of the chosen southeastern site for the in-soil Radon monitoring at Mt. Etna. The comparison of the recorded Radon concentration anomalies with seismicity and volcanic tremor trends, has also verified a possible link with the volcanic activity, as observed in our previous published studies.     

An integrated analytical characterization of corrosion products on ornamental objects from the necropolis of Colle Badetta-Tortoreto (Teramo, Italy)

Selected groups of copper-based artifacts found during archaeological excavations of the necropolis of Colle Badetta-Tortoreto (Teramo, Italy) were investigated in order to determine the chemical composition and metallurgical features of the alloys and the micro-chemical and micro-structural nature of the corrosion products grown during the long-term burial. The investigated Cu-based artifacts were ornamental objects, such as rivets, buckles and small rings that were applied to large belts to form complex patterns with the addition of small and large shaped pieces of amber. The analytical characterization was performed by using different surface and bulk techniques, such as Optical Microscopy (OM), Scanning Electron Microscopy coupled with energy dispersive X-ray micro-analysis (SEM-EDS), X-ray Diffraction (XRD).     

New criterion for in situ,quick discrimination between traditionally maintained and artificially restored Japanese swords (katanas) by XRF spectroscopy

For the first time, a quick method to discriminate between undamaged, well‐maintained katanas and worn artificially restored blades is presented. The peculiar hardening process that a Japanese katana undergoes results in creation of a tempered martensitic phase near the blade edge. After the temper, traditional polishing with stones is performed, which gives the sword its final look: the hardened zone exhibits matte finish, and it is separated from the shinier zone by the hamon line, which is the most characteristic feature of a katana. If the sword is worn, the martensitic phase disappears and so does the hamon line, the sword losing most of its commercial value. However, an acid bath can simulate the matte texture of an undamaged martensitic structure, making it really difficult to recognize valuable blades from worn ones. So far, no analytical approach helping in this task was available. The method we present is based on the hypothesis that traditional polishing leaves a very tiny amount of stone dust on the blade, whereas the acid bath rinses it away. The presence on the blade surface of Si (the major component of the stones used for polishing) when the hamon line is clearly visible could thus be a reasonable marker indicating that the blade is maintaining its original martensitic structure and thus is in a good conservation state. For the Si detection, X‐ray fluorescence technique was chosen, which ensures non‐destructivity, high sensitivity, and short measurement time with a portable instrument. Copyright © 2013 John Wiley & Sons, Ltd.     

Determination of (15)N in (15)N-enriched nitrite and nitrate in aqueous samples by reaction continuous flow quadrupole mass spectrometry

The (15)N tracer method is the most suitable method for studying complex N transformation processes in microbiology and biochemistry. It entails the constant determination of the (15)N abundance of the inorganic nitrogen (N) compounds nitrite and nitrate. However, (15)N analytical methods are time-consuming, difficult to automate, and require at least 10 μg of N per determination. An additional obstacle in the case of nitrite is that it usually only occurs in very small amounts (ppb) dwarfed by much larger quantities of nitrate (ppm). More useful is an approach in which the N compound is selectively converted into a gaseous form suitable for direct measurement by mass spectrometry. By using this 'reaction continuous-flow mass spectrometry' (R/CFMS) we developed methods for the (15)N determination of nitrite and nitrate from tracer experiment samples, i.e. artificially enriched in (15)N. Because both methods are based on the same principle, one continuous flow setup connected directly to a quadrupole mass spectrometer for all determinations was used. Nitrite and nitrate are reduced to NO by iodide and titanium(III) chloride, respectively. The technique developed ensures a precision of relative standard deviation /=1 at.% are to be measured for nitrite and nitrate, respectively. Copyright 1999 John Wiley & Sons, Ltd.     

On the aging characterization of poly(ethylene terephthalate) by positron spectroscopy

Positron spectroscopy was used to study the free volume properties of glassy poly(ethylene terephthalate) as a function of temperature and aging time. The experimental results indicate that the glass transition temperature increases with increasing aging time. This is confirmed by differential scanning calorimetry measurements. From the aging time dependence of the intensity of the ortho-positronium (o-Ps) component I₃ and the fractional free volume, we observe that the concentration of free volume holes and the fractional free volume show a continuous decrease at a fixed aging temperature, which suggests that structural relaxation and segmental rearrangement occur during physical aging.     

Precise half-life measurement for the superallowed 0(+)-->0(+) beta emitter (74)Rb: first results from the new radioactive beam facility (ISAC) at TRIUMF

Presently, the world data for superallowed beta decay leads to a result in disagreement (at the 98% confidence level) with the predictions of the minimal standard model for the unitarity of the Cabibbo-Kobayashi-Maskawa matrix. Precise data for the superallowed 0(+)-->0(+) beta decay of (74)Rb would provide a critical test of the nucleus-dependent isospin symmetry-breaking corrections that must be calculated for these superallowed Fermi beta decays. The present work reports the first precise measurement of the half-life for (74)Rb ( t(1/2) = 64.761+/-0.031 ms). The data were obtained at the radioactive beam facility (ISAC) at TRIUMF using a beam of approximately 4000 (74)Rb ions s(-1).     

Morpho-functional characterization and esterase patterns of the midgut of Tribolium castaneum Herbst, 1797 (Coleoptera: Tenebrionidae) parasitized by Gregarina cuneata (Apicomplexa: Eugregarinidae)

Tribolium castaneum (Coleoptera: Tenebrionidae) is a common pest of stored grains and byproducts and is normally infected by Gregarina cuneata (Apicomplexa: Eugregarinidae). The life cycle of this parasite includes the sporozoite, trophozoite, gamont, gametocyte, and oocyst stages, which occur between the epithelium and lumen of the host's midgut. This study aims to describe the morphofunctional alterations in the midgut and determine the esterase patterns in T. castaneum when parasitized by gregarines. To achieve this purpose, midguts of adult insects were isolated, processed, and analysed using light and electron microscopy. We determined total protein content, amylase activity, and the expression and related activities of the esterases by using polyacrylamide gel electrophoresis (PAGE). The midgut of T. castaneum is formed by digestive, regenerative, and endocrine cells. The effects of parasitism on the digestive cells are severe, because the gregarines remain attached to these cells to absorb all the nutrients they need throughout their development. In these cells, the most common alterations observed include expansion and fragmentation of the rough endoplasmic reticulum, development of the smooth endoplasmic reticulum, changes in mitochondrial cristae, cytoplasmic vacuolization, formation of myelin structures, spherites, large intercellular spaces, autophagic vesicles, expansion of the basal labyrinth, and cytoplasmic protrusions. Deposits of glycogen granules were also observed. Amylase activity was reduced in parasitized insects. Regenerative cells were found in disorganized crypts and did not differentiate into new cells, thus, compromising the restoration of the damaged epithelium. Though few morphological alterations were observed in the endocrine cells, results suggest that the synthesis and/or release of hormones might be impaired. Nine esterases (EST-1 to 9) were identified in the midgut of T. castaneum and were expressed in varying levels in response to parasitism. Two additional isoforms of esterases were exclusively identified in the parasitized insects. The results of this study suggest that gregarines alter the morphology and physiology of the midgut. The changes may result in nutritional depletion and the impairment of other physiological processes, such as reproduction and development of the host. Thus, further studies are needed to uncover the possibility of utilizing gregarines as biological controllers of the insect pest population.     

Natural and anthropogenic variations in the Po river waters (northern Italy): insights from a multi-isotope approach

Po is the main Italian river and the δ¹⁸O and δ²H of its water reveal a similarity between the current meteoric fingerprint and that of the past represented by groundwater. As concerns the hydrochemisty, the Ca–HCO₃ facies remained constant over the last 50 year, and only nitrate significantly increased from less than 1?mg/L to more than 10?mg/L in the 1980s, and then attenuated to a value of 9?mg/L. Coherently, δ¹³C_DIC and δ³⁴S_SO4 are compatible with the weathering of the lithologies outcropping in the basin, while extremely variable δ¹⁵N_NO3 indicates contribution from pollutants released by urban, agricultural and zootechnical activities. This suggests that although the origin of the main constituents of the Po river water is geogenic, anthropogenic contributions are locally significant. Noteworthy, the associated aquifers have the same nitrogen isotopic signature of the Po river, but are characterized by significantly higher NO^– ₃ concentration. This implies that aquifers’ pollution is not ascribed to inflow of current river water, and that the attenuation of the nitrogen load recorded in the river is not occurring in the aquifers, due to their longer water residence time and delayed recovery from anthropogenic contamination.     

Cerebral hemodynamic response in Chinese (first) and English (second) language processing revealed by event-related functional MRI.

Comparative functional neuroimaging studies using the block design paradigm have previously demonstrated that there are no significant differences in the location of areas of cerebral activation when native Chinese speakers independently process single words or sentences in both the Chinese (first) and English (second) languages. While it has also been documented that significant domains of brain response include the inferior to middle left frontal lobe, the latency, amplitude and duration of the associated hemodynamic changes during isolated neural processing of Chinese and English languages still remain unknown. The aim of this study, therefore, was to examine the characteristics of the hemodynamic alterations in the above-mentioned regions with event-related functional MRI (ER-fMRI) when native Chinese speakers performed verb generation tasks in both the Chinese (first) and English (second) languages. Our results demonstrate the presence of a similar neural activity-induced hemodynamic response in the inferior to middle left frontal lobe during both tasks. Further, there were also no statistically significant differences among the variables that described the hemodynamic response curves. These findings strongly imply that the underlying neural mechanism for Chinese (first) and English (second) language processing may be similar in native Chinese speakers.