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Ecotoxicology has emerged as a discipline that aims to identify and predict the effects caused by anthropogenic pollutants defined as emerging on ecosystems. Worrisome are engineered nanoparticles and microplastics found in many consumer products but also chemicals and drugs found in both marine and freshwater aquatic ecosystems. Although the in vitro study is supported by the authorities, continuing evidence indicates that in vivo testing is of extreme relevance in bioscience. X. laevis is a very relevant model for both environmental and biomedical studies (Carotenuto et al., 2016, 2020, 2021, 2022). It allows studies on gametogenesis and embryogenesis as well as on the juvenile and adult stages. Furthermore, compared to alternative models of invertebrates and vertebrates, it shows greater genetic homology and pathways that can be superimposed on mammals, including humans, so the data obtained can be easily translated (Takagi et al., 2013; Session et al., 2016; Tandon et al., 2017). The literature strongly suggests that Xenopus has all the characteristics required of a model organism for studies on bio-interactions and adverse effects of pollutants, also in the perspective of a safe development of new materials (Libralato et al., 2017). The use of this amphibian in the laboratory, offers some advantages: 1) eggs can be obtained almost all along the year by injecting females with gonadotropic hormones and in vitro fertilization is easy to perform; 2) the ease of manipulating of gametes, embryos and adult; 3) the direct visualization of organs morphogenesis; 4) the relative ease of manipulating of gene expression and genetic engineering (Takagi et al., 2013; De Marco et al., 2017) 5) the genome have been completely sequenced (Session et al., 2016) and has a high percentage of homology with that of humans; 6) the availability of Xenopus genetic and genomic data to study genes, gene families and gene networks, including ESTs (expressed sequence tags) (Sczyrba et al., 2005), 7) UniGene clusters continually update genomic sequences for the use of technologies as RNA-Seq (Amin et al., 2014) and quantitative proteomics (Sun et al., 2014). Furthermore, the National Xenopus Resource (NXR), the European Xenopus Resource Centre (EXRC), and other stock centers, have an increasing resource of transgenic lines; 8) the possibility to use techniques for modifying gene expression (morpholino) (Takagi et al., 2013; De Marco et al., 2017), and genome editing techniques like the CRISPR/Cas9 system (Naert et al., 2020). The possibilities offered by X.laevis are an excellent link to undertake cooperation in the study of one of the most challenging environmental aspects, the activity of pollutants on biota including humans.

Lanthanides are present everywhere on the earth’s crust with relatively wide concentration ranges and a toxicity considered low. Gadolinium (Gd) is one of the most widespread; it is used in technological devices and in contrast media for diagnostic imaging. Its concentration in the rivers of industrialized, densely populated areas is often anomalous; in Germany, for example, it is up to three orders of magnitude higher than the expected natural values1. Many aquatic organisms are vulnerable to lanthanides2. Few studies have analyzed their potential long-term effects infreshwater. We used Xenopus laevis as a model system and the FETAX assay3,4, the expression of genes involved in early embryonic development and the ROS production to evaluate the possible toxic effects of Gd. We also verified whether it could activatethe multixenobiotic resistance mechanisms (MXMR) and induce an immune response. The embryos were exposed to Gd ions ranging from 0.2μg/L to 80μg/L considering the environmental concentrations. The FETAX assay showed that Gd is not lethal to Xenopus embryos; between 40 and 80μg/L, the treated embryos reach longer lengths than the controls and at 40μg/L 15% are malformed. As concentration increases, embryos show tachycardia and total ROS production increases. Finally, Gd modifies the expression of early embryonic genes, stimulates the production of cytokines at highest concentrations and activates the MXMR pump at the lowest. These data indicate that Gd, although not lethal for embryos, modifies their growth and exerts a slight toxic/teratogenic effect; it also induces tachycardia and activates the immune response. The observed phenotypic modifications are ascribable to modifications in the expression of genes responsible for the “construction” of the tadpole. This may be due to the production of ROS, which is known to affect gene expression, but also to the difficulty of embryos to activate MXMR. However, the most interesting results are visible at the highest concentrations used.

Delorazepam, a derivate of diazepam, is a psychotropic drug belonging to the benzodiazepine class. Used as a nervous-system inhibitor, it treats anxiety, insomnia, and epilepsy, but is also associated with misuse and abuse1. Nowadays benzodiazepines are considered emerging pollutants2: conventional wastewater treatment plants indeed are unable to completely eliminate these compounds3. Consequently, they persist in the environment and bioaccumulate in non-target aquatic organisms4. The impact and consequences are still not fully clear. To collect information, we tested the effects of three increasing concentrations of delorazepam (1, 5, and 10 g/L) on Xenopus laevis embryos, a representative model of amphibians, a particularly endangered class of aquatic organisms. Results demonstrate that, besides being sedative, delorazepam is teratogenic and able to induce relevant changes in gene expression and in the oxidative state. New analysis highlighted an epigenetic effect of delorazepam, which induces an increase in methylation of the genomic DNA of the tadpoles and a differential methylation of the promotors of some early developmental genes. Parallel histological investigationhighlighted retinal disorganization, indicative of interference on the developing nervous system, and suggestive of visual defects. Results are alarming considering the growing trend of benzodiazepinesconcentrations in superficial waters5 and the fact that benzodiazepines receptors are present in all aquatic organisms.

Microplastic represents a class of contaminants of emerging concern due to the numerous interferences exerted on biological processes1. Among these, developmental processes should be included2 and the effects of microplastic on zebrafish and sea urchins’ embryos are now well documented3. In particular,microplastics accumulate in the yolk4 but no much attention has been dedicated to the potential effects they exert on yolk degradation during early embryogenesis. For this reason, we carried out a preliminary investigation in an oviparous model, Artemia salina. Cysts were hatched and nauplii grew for 5 days in presenceof virgin and non-virgin polystyrene fragments (mixture, max diameter 10 μm) and, for control, in presence of polystyrene microbeads (3 μm; Sigma-Aldrich). Histological analyses confirm5 that in control cysts and in nauplii at stages L1 and L2 yolk platelets are very numerous. They reduce significantly in nauplii at stage L3 and disappear in nauplii at stage L4. After microplastic exposure, no matter the type, not only cysts and nauplii at stages L1 and L2, but also a significant percentage of nauplii at stages L3 and L4 contain a vast number of yolk platelets. These are occasionally located in the gut cells, but most often are dispersed in intracellular spaces. Persisting platelets have a different glycan composition as indicated by staining with a panel of lectins (WGA, DBA, and PNA). Though preliminary, results open up an interesting new field of research. Microplastic, in fact, represents worldwide a serious emerging environmental threat to health being a proven vehicle for contaminants6. Our evidence suggests a much more direct impact onwater organisms and recruitment mechanisms.

Purpose The diagnosis of vitamin D deficiency is based on the determination of total plasma 25-hydroxyvitamin D (25-OHD) concentrations, but the regulation of vitamin D 25-hydroxylation is not a major consideration and very little information is available on this activity. To check what factors could interfere with the activity of vitamin D-25-hydroxylase and thus alter the 25-OHD concentrations, we looked for potential correlations between 25-OHD and results of liver function tests in healthy adults. Methods This single-centre study was retrospective and consisted of evaluating the correlations between 25-OHD and the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), and bone alkaline phosphatase (BALP) in 349 healthy subjects aged from 18 to 65 years. In particular, in Group 1 (n = 119), we looked for correlations between 25OHD and all liver function tests and in Group 2 (n = 230) the correlation between 25OHD and BALP. Results In Group 1, we found no correlation between 25OHD and AST (r = − 0.03; p = 0.8), ALT (r = − 0.02; p = 0.91), GGT (r = − 0.08; p = 0.68), direct bilirubin (r = − 0.02; p = 0.89), indirect bilirubin (r = − 0.24; p = 0.21), and total bilirubin (r = − 0.24; p = 0.21) but one between 25OHD and ALP (r = − 0.2; p = 0.007); in Group 2, we found a significant negative correlation between 25-OHD and BALP (r = − 0.2; p = 0.0008). Conclusions The correlations that we found suggest that ALP and BALP might be involved in the regulation of vitamin D-25-hydroxylase activity, but further studies are mandatory to confirm our assumptions.

The use of lanthanides, also known as rare earth elements (REEs), in technological devices and their presence in the e-waste made them a new category of potential emerging contaminants (Gravina et al., 2018; Pagano et al., 2019). Their toxicological and ecotoxicological effects are still largely unknown. Erbium is one of the most widespread REEs with potential environmental and human health risks associated to its increased release (Tornero and Hanke, 2017). Reported lanthanides concentrations in the surface water usually vary from 10 ng/L to 200 ng/L (Neal, 2007); however, in the very polluted rivers lanthanides concentrations may increase up to 10 μg/L (Neal et al., 2005). Only few studies investigated the potential effects of REEs on a long-term basis in freshwater (Blaise et al., 2018; Blinova et al., 2018). The aim of our study is to examine the influence of Erbium on Xenopus laevis embryos, organism never experimented with this lanthanide, to test the eventual adverse effects on developing organisms. We used environmental (1 and 10 μg/L) and twice higher (20μg/L) concentrations. Our preliminary data indicate that Erbium induces alteration of morphology, with cephalic and abdominal edema and anomalous intestinal winding, ROS production and decreased heart rate, thus suggesting that erbium could be dangerous for X. laevis and other non-target species.

Benzodiazepines, used for the treatment of sleep disorders, anxiety, and epilepsy, represent an important class of emerging poll-tants1. As occurs for most pharmaceutical residues, they are released into the wastewater but not degraded during sewage treatment 2therefore accumulating in effluent waters at concentrations ranging from μg/L to ng/L3. The resulting environmental concentrations may come close to human therapeutic plasmaconcentrations4. Bioaccumulation is already reported in fish 5and small crustaceans 6as significant effects on behavior, gene expression, and enzymes activity. Environmental and human health protection prompt a more accurate estimate of the impact of this drug on non-target aquatic organisms and, in particular, on early developmental stages. Therefore, in this study, we investigated the effects of the benzodiazepine Delorazepam on Xenopus laevisembryos. Environmental (1 mg/L)7and 5 and 10times higher (5 and 10 mg/L) concentrations were tested. Preliminary trials indicate that the drug reduces vitality(decreased heart rate and motility), induces marked cephalic and abdominal edema, and causes morphological alterations in the gut. At the molecular level, altered expression of developmental genes is observed together with the production of inflammatory molecules. The resulting stress condition significantly impairs embryo development and threatens their survival. Similar effects should be expected also in embryos belonging to other aquatic species though so far, they have not been considered tar-get for benzodiazepines.

The applications in technologies of lanthanides, as Cerium and Erbium, have made them as emergent contaminants with a toxic impact on environment. Recent literature, highlights their ecotoxicity, bioaccumulation and action in order to predict the possible environmental risks. Few studies focused on the toxicity effects linked to their intracellular concentration on Daphnia magna1-3 wich is an excellent biomonitoring aquatic species4. To date, ecotoxicological experiments based on multi-generational field exposures are still little considered. In this study, chronic multigenerational effects on D. magna were assessed using various exposure times (3, 7, 14, and 21 days) in three generations (F0, F1 and F2). Each generation was exposed to environmental concentrations of Ce (0.54 μg/L ) and Er (0.43 μg/L) and the effects included: organisms’ size, reproduction, survival, ROS determination, activity of SOD, CAT and GST, expression of ABC transporter5, and uptake. Results evidenced that chronic multi-generational exposure of daphnids reduced survival, growth and reproduction, increasing ROS, SOD and CAT from F0 to F2. Ce reduced the number of offsprings after each generation, while Er delayed the time of offspring emergence, but not their number. ROS, SOD, CAT and GST evidenced that Er is slightly more toxic than Ce. Up- and downregulation of genes was limited, but Ce and Er activated the ABC transporters. Their uptake decreased through exposure time and generations.

The assessment of the structural and functional pavement condition is nowadays fully machine based and non-destructive equipment does cover all the data input required for a modern PMS approach. A Multi-Laser Vehicle is capable of real time continuous traffic-speed measurements of condition data regarding cracking, ravelling, rutting, roughness, macro texture and road geometrics in a single run using high-speed line-scan cameras for an automated assessment. The system of the Multi-Laser Vehicle equipped with a Laser Crack Measuring System (LCMS) is the most promising development in 3D camera technology with a progressive improvement of capabilities and quality. This paper discusses the results of the equipment used as well as the accuracy and repeatability achieved. Shown is as well the continuous measured macro texture based on the Mean Texture Depth (MTD) as index using the LCMS device in addition to the automated crack detection. A major advantage is that no conversion is required as the volumetric MTD is a direct output. The LCMS based automated MTD analysis is a machine based result not influenced by a human factor such as the Sand Patch. The results allow as well the automated analysis of loss of aggregate which is a major advantage in rating the severity and extent of ravelling in comparison to the non-consistent wind-screen surveys and manual rating of collected images. In addition to the MTD the sampling of rutting has been validated against the multi-laser profiler approach as well as the International Roughness Index (IRI) based on Inertial Motion Units (IMU’s) attached to the LCMS sensors.

This study aimed at developing a test using an autochthonous collembolan species ( Orthonychiurus pseudostachianus , Gisin 1956) to assess soil toxicity. To evaluate the feasibility of this species in soil ecotoxicity assessment, it was considered whether the biological characteristics of the proposed species met the criteria reported in OECD guideline 232 for toxicity testing using Folsomia candida . Next, the sensitivity to soil metal contamination was evaluated performing the test on an artificial soil spiked with Zn concentrations ranging from 4.79 to 479 μg g −1 d.w. To verify its suitability for soil ecotoxicity assessment, the proposed test was performed on soils collected at six sites in the urban area of Naples together with other ecotoxicological tests. The other aim of the study was to identify the lowest number of tests needed to obtain an optimized test battery for soil ecotoxicity assessment. At the tested Zn concentrations, no mortality of O. pseudostachianus was observed whereas reproduction was halved at 37.4 μg Zn g −1 d.w. (95% confidence limits 29.3–44.8). In the field-collected soils, reproduction of O. pseudostachianus proved a useful tool to assess soil quality. A test battery composed only by Sinapis alba (germination index), O. pseudostachianus (reproduction), Eisenia veneta (body growth), and Heterocypris incongruens (body growth) tests were shown to be sufficiently informative to assess soil toxicity.

Egg allergy is a contraindication for influenza vaccination because of the presence of trace egg protein. Although recent reports suggest that egg-allergic individuals can be safely immunized with seasonal influenza vaccine, the safety of H1N1 influenza vaccine in this context has not previously been reported. This study was designed to investigate how to safely immunize high-risk populations during the H1N1 influenza pandemic for whom the vaccine would be contraindicated. Vaccination of egg-allergic children was conducted at a large, multispecialty practice. Pediatricians raised awareness of vaccination and referred egg-allergic individuals to allergists. Allergists performed skin testing to H1N1 vaccine and, if negative, performed graded vaccine desensitizations in the office. Mass immunization of egg-allergic individuals was achieved within a 3-week period after receipt of vaccine. Sixty-three children (average age, 3.7 years) were evaluated and skin tested to the H1N1 influenza vaccine. All had a clinical history of egg allergy and recent positive skin-prick to egg. All had negative skin-prick test to the H1N1 vaccine and received graded challenge with three divided doses. All 62 children were successfully immunized without allergic reactions. Vaccination of egg-allergic individuals during a pandemic can be safely and efficiently accomplished with the coordination of multidisciplinary resources. Although this was conducted at a multispecialty practice, we believe that this invaluable public health service can be done outside of this context. Allergists, with the help of local pediatricians and urgent care centers or hospitals, can effectively mobilize to help protect the most vulnerable populations during pandemics.

The use of microorganisms to accelerate the natural detoxification processes of toxic substances in the soil represents an alternative ecofriendly and low-cost method of environmental remediation compared to harmful incineration and chemical treatments. Fourteen strains able to grow on minimal selective medium with a complex mixture of different classes of xenobiotic compounds as the sole carbon source were isolated from the soil of the ex-industrial site ACNA (Aziende Chimiche Nazionali Associate) in Cengio (Savona, Italy). The best putative degrading isolate,Methylobacterium populiVP2, was identified using a polyphasic approach on the basis of its phenotypic, biochemical, and molecular characterisation. Moreover, this strain also showed multiple plant growth promotion activities: it was able to produce indole-3-acetic acid (IAA) and siderophores, solubilise phosphate, and produce a biofilm in the presence of phenanthrene and alleviate phenanthrene stress in tomato seeds. This is the first report on the simultaneous occurrence of the PAH-degrading ability byMethylobacterium populiand its multiple plant growth-promoting activities. Therefore, the selected indigenous strain, which is naturally present in highly contaminated soils, is good candidate for plant growth promotion and is capable of biodegrading xenobiotic organic compounds to remediate contaminated soil alone and/or soil associated with plants.

Cytoskeletal proteins such as actin and myosin are important constituents of the nucleoplasm. Spectrin is an actin binding protein typically related to plasma membrane; recently, it has been found that it is widespread and forms distinct membrane protein domains in such organelles as the Golgi. In this paper, the large germinal vesicle of amphibian oocytes was chosen as a particularly suitable system to investigate the presence and location of spectrin in the nucleus. We manually isolated the germinal vesicles of both Discoglossus pictus and Xenopus laevis oocytes, and processed them for SDS-PAGE, immunoblotting and immunoprecipitation. By the use of an antibody against the general form of brain beta spectrin (betaIIsigma1) and of an anti-alpha brain spectrin (alphaIIsigma*), a band of 230 kDa was identified as a nuclear spectrin-like molecule. Moreover the 230 kDa protein was extracted from the nuclei by 1 M KCl, similarly to spectrin in other systems. In oocyte sections and nuclear spreads incubated with anti-alphaIIsigma* and/or anti-betaIIsigma1 antibodies, the immunostain was localised in the nucleoplasm and in the outer shell of the round bodies abundantly present in the germinal vesicle. Sections of the same oocytes, stained with a monoclonal antibody against nucleolar fibrillarin and anti-alphaIIsigma*, showed co-localisation of the two antibodies. It was concluded that, in the germinal vesicle of amphibian oocytes, a spectrin-like molecule is a part of the outer shell of nucleoli. It is hypothesised that spectrin, together with actin, might be instrumental in keeping nucleoli attached to the inner nuclear membrane, as nucleoli migrate during oogenesis to the inner aspect of the nuclear envelope, where they are stably kept until the end of their growth. Furthermore, these results strongly suggest that the 230 kDa band might comprise both an alpha and a beta chain of the same apparent molecular mass, thus constituting a novel form of a spectrin-like molecule.

Nine Burley tobacco cultivars were tested in three locations of the Veneto region during 3 years in order to single out the ones most suitable for the target environment. Differences among cultivars were found for plant development indicators, yield and visual quality of the cured leaf, but not for physical and chemical properties of the leaf, even if most characters varied widely among the environments. High yields combined well with high scores of Quality Index. F1, hybrids CAS 83–1E and C. 03–6 resulted on average the best performing cultivars, both for yield and quality, confirming the findings of previous trials.

In the IEEE Standard on piezoelectricity the electromechanical coupling factor is defined in static conditions as the ratio between the converted and the total energy involved in a transfor-mation cycle (kmat). In this work we show that this definition can also be extended to dynamic cases: by means of 1–D models we demonstrate that, for loss less piezoelectric elements vi-brating in the rod (longitudinal) or width (transverse) mode, the k factor can be defined as the square root of the ratio between the converted electric energy and the kinetic total energy; the obtained results are proportional to the appropriate kmat.

From 1985 to 1987, eight varieties of domestic and foreign Burley tobacco were studied in some Northern Italy locations (Veneto Region), as an alternative to the air-cured light and dark tobacco presently grown in that area. An average 3-year yield equal to or higher than 3 t ha of cured leaf was obtained for all the tested varieties, which indicates a general adaptation to the environment. Early-flowering types were more productive than late-flowering ones; the qualitative leaf traits (alkaloid content, combustibility and specific leaf weight) were mainly related to the growing seasons. The yield stability test and the mean leaf yields highlighted the CAS 83–1A and CAS 83-lE cultivars as high-yielding and stable genotypes, and Virginia 528 as a medium to high yielding genotype adapted to less favourable conditions.

This study aimed to assess soil quality by chemical and ecotoxicological investigations and to check the correspondence between soil metal concentrations and ecotoxicity. For these purposes, surface soils collected at four adjacent roadside urban parks and at a former industrial area were characterized for C/N, organic matter content, texture, and pH. Cr, Cu, Ni and Pb, chosen among the most representative soil metal contaminants, were measured as total content and as available and water soluble fractions. In addition, the total concentrations of the investigated metals were used to calculate two chemical indices: the contamination and the potential ecological risk factors. The toxicity of the investigated soils was evaluated by an ecotoxicity test battery carried out on both soil samples (Vibrio fischeri, Heterocypris incongruens and Sinapis alba) and elutriates (Vibrio fischeri, Daphnia magna and Selenastrum capricornutum). The findings, both by the chemical and ecotoxicological approaches, would suggest that the soils with high metal contamination pose ecological risks. On the other hand, moderately metal contaminated soils did not exclude soil ecotoxicity. In fact, toxic effects were also highlighted in soils with low metal content, toxicity being affected by metal availability and soil characteristics. Moreover, the results suggest the importance of using a battery of tests to assess soil ecotoxicity.

The fate and the behaviour of nanoparticles in seawater, which is the ultimate sink for any release of nanoparticles, is a very important issue for the assessment of their environmental impact. Despite this concern, only few studies regarding the ecotoxic effect of NPs upon marine organisms were conducted. In this work the dispersion behaviour of NPs in a seawater matrix has been investigated and their physicochemical properties characterized. The ecotoxicological impact towards marine organisms of several nanoparticles has been also examined.

Nanomaterials have widespread applications in several industrial sectors. ZnO nanoparticles (NPs) are among the most commonly used metal oxide NPs in personal care products, coating and paints. However, their potential toxicological impact on the environment is largely unexplored.The aim of this work was to evaluate whether ZnO nanoparticles exert toxic and genotoxic effects upon terrestrial organisms: plants (Lepidium sativum, Vicia faba), crustaceans (Heterocyipris incongruens), insects (Folsomia candida). To achieve this purpose, organisms pertaining to different trophic levels of the soil ecosystem have been exposed to ZnO NPs. In parallel, the selected soil organisms have been exposed to the same amount of Zn in its ionic form (Zn(2+)) and the effects have been compared.The most conspicuous effect, among the test battery organisms, was obtained with the ostracod H. incongruens, which was observed to be the most sensitive organism to ZnO NPs. The root elongation of L. sativum was also mainly affected by exposure to ZnO NPs with respect to ZnCl(2), while collembolan reproduction test produced similar results for both Zn compounds. Slight genotoxic effects with V. faba micronucleus test were observed with both soils.Nanostructured ZnO seems to exert a higher toxic effect in insoluble form towards different terrestrial organisms with respect to similar amounts of zinc in ionic form.

Optical fingerprint scanners suffer from limited depth of penetration and are particularly sensitive to the surface conditions of the skin. Fingerprint scanners based on ultrasounds offer the possibility to explore the surface and the underlying tissues of the finger and to detect blood flow, leading to enhanced robustness and reliability in biometric applications. Capacitive Micromachined Ultrasonic Transducers (cMUTs) have shown to have great potential for use in medical imaging applications. The ease of fabricating broadband high-frequency ultrasound transducers makes the cMUT technology a good candidate for ultrasound based biometrics. This paper presents the design, fabrication and characterization of a cMUT linear array probe optimized for near-field ultrasound imaging. Ultrasound images of fingerprints are obtained using a customized 3D ultrasound scanning system.

The presence and localization of α- and β-spectrins and of the spectrin cross-linking protein actin were investigated, in previtellogenic oocytes of three species of Antarctic teleosts: the two red-blooded nototheniids, Trematomus bernacchii and Trematomus newnesi, and the channichthyid, the ice fish Chionodraco hamatus. Analyses by western blotting indicated that these species had an unusual abundance of spectrin isoforms and that they were characterized by rather low molecular masses. The immunocytochemistry in situ demonstrated that α- and β-spectrins showed a variable pattern of localization that clearly depended on both the species considered and the stage of oocyte differentiation. In particular, the two Trematomus spp. showed a distribution of spectrins absolutely comparable and rather different from that of C. hamatus. The evidences collected confirmed that channichthyids have isolated early from the group of red-blooded species and suggest that in notothenioids significant changes might have occurred in spectrin genes and in their protein products.

Xenopus oocyte organization largely depends upon the cytoskeleton distribution, which is dynamically regulated during oogenesis. An actin-based cytoskeleton is present in the cortex starting from stage 1. At stages 4-6, a complex and polarized cytoskeleton network forms in the cytoplasm. In this paper, we studied the distribution of spectrin, a molecule that has binding sites for several cytoskeletal proteins and is responsible for the determination of regionalized membrane territories. The localization of alpha-spectrin mRNA was analyzed during Xenopus oogenesis by in situ hybridization on both whole mount and sections, utilizing a cDNA probe encoding a portion of Xenopus alpha-spectrin. Furthermore, an antibody against mammalian alpha-spectrin was used to localize the protein. Our results showed a stage-dependent mRNA localization and suggested that spectrin may participate in the formation of specific domains in oocytes at stages 1 and 2 and 4-6. Mol. Reprod. Dev. 55:229-239, 2000.

(...) The objectives of the investigation were to determine the range of values of chromaticity parameters of visually graded leaves and to evaluate the possibility of utilizing the parameters for electronic screening. The classification of leaves (visually or mechanically) is generally based on the evaluation of chromaticity differences of their color. The success of electronic screening requires an accurate definition of the chromaticity parameters a * , b * , and L * , which were defined mathematically by the International Commission on Illumination

The use of 4H-SiC junction devices as effective temperature sensors is demonstrated by measuring, elaborating and comparing the experimental I- V characteristics of three different devices, namely pin and Schottky diodes and the body diode of a commercial power MOSFET. Due to the strong dependence of the I-V characteristics on temperature, the sensor performs a high sensitivity. It is shown that the correct choice of the probe current during sensing is fundamental to obtain an excellent linearity with T in the sensor response.

High-frequency transducers, up to 35-50 MHz, are widely used in ophthalmic echography to image fine eye structures. Phased-array techniques are not practically applicable at such a high frequency, due to the too small size required for the single transducer element, and mechanical scanning is the only practical alternative. At present, all ophthalmic ultrasound systems use focused single-element, mechanically scanned probes. A good probe positioning and image evaluation feedback requires an image refresh-rate of about 15-30 frames per second, which is achieved in commercial mechanical scanning probes by using electromagnetic motors. In this work, we report the design, construction, and experimental characterization of the first mechanical scanning probe for ophthalmic echography based on a small piezoelectric ultrasound motor. The prototype probe reaches a scanning rate of 15 sectors per second, with very silent operation and little weight. The first high-frequency echographic images obtained with the prototype probe are presented.

In this work, a new piezoelectric motor is described wherein the stator is a bolted Langevin structure excited in flexural vibration. Two piezoelectric disks are sandwiched by two cylindrical inertial masses and their metallization is divided in four sectors. By applying suitable electrical signals to the four sectors, a traveling rotating thickness deformation is excited, and if the structure is excited at its natural flexural frequency, a well-sustained traveling rotating flexural deformation takes place in the Langevin vibrator. The bolt exceeds in length the inertial masses of the Langevin vibrator, acting as a central axle animated by a wide precessional motion. The rotor is a cylindrical permanent magnet pressed in contact with the top surface of the axle by means of a little nylon axle. A slipping takes place between the stator and the rotor and a torque is generated. The motor is able to give relatively high speed ( 2800 rpm) and torque (15 muN m). The very robust structure of the stator makes this motor easy scalable in size and suitable for high power applications. A simple mathematical model to design the working frequency of the stator is described; theoretical results and experimental measurements were compared. (C) 2004 Elsevier B.V. All rights reserved.

Capacitive microfabricated ultrasonic transducers (cMUTs) are the newest and potentially the most promising devices to convert electrical into acoustic signals and vice-versa. These devices are based on the capacitance modulation of a microcondenser which is obtained by microfabrication onto a silicon substrate. The aim of this paper is to describe a PSpice model of the cMUT, based on an analytical distributed model previously reported (IEEE Trans. UFFC 49 (2) (2002) 159-168), which can be used to simulate the performances of a general ultrasound system, either in frequency or time domain. The PSpice model consists of a capacitor with a parallel resistor, which represent the static capacitance and the loss and bias resistances of the transducer, respectively, plus two quadrupoles (GLAPLACE) modeling the mechanical impedance of the membranes and the radiation impedance of the medium. The usefulness of a PSpice model is the possibility to simulate and optimize the cMUT transducers in transmission and reception, along with driving and receiving electronics, in a general ultrasound system. Experimental measurements on a 5 MHz cMUT operating in pulse-echo are in good agreement with model predictions.

Soils represent the final destination of pollutants coming from both air and water inputs. Heavy metals are of primary concern as they persist in the environment, move up the food chain and could cause several disorders. The aim of this study was to compare the metal contamination and ecotoxicity of two soils at different use, urban and agricultural. Different toxicity tests were performed both with whole soil and its aqueous extract by a battery of ecotoxicological test with organisms belonging to different trophic levels: bacteria (Vibrio fischeri), algae (Selenastrum capricornutum), plants (Sorghum saccharatum, Lepidium sativum, Sinapis alba) and crustaceans (Daphnia magna, Heterocypris incongruens). Moreover the genotoxic effects were assessed by Vicia faba micronucleus assay. The content of some trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and their available fractions were also determined. Urban soil exerted a moderate toxicity upon V. fischeri and a clear biostimulation upon S. alba, instead of soil aqueous extract produced only algae growth biostimulation. Higher genotoxic effects observed for urban soil could be attributable to lead content and availability. Agricultural soil was mainly contaminated by Cu which could be responsible of bacteria bioluminescence inhibition. Agricultural soil aqueous extract revealed high toxicity on S. capricornutum growth; moreover genotoxic effects were not evidenced. The integration of toxicity data in the ecotoxicological risk index showed a clear difference between investigated soils, with the highest risk values for agricultural one.