Coherence of PRNU weighted estimations for improved source camera identification

Multimedia Tools and Applications - This paper presents a method for Photo Response Non Uniformity (PRNU) pattern noise based camera identification. It takes advantage of the coherence between...     

Dexamethasone inhibition of interferon-alpha 2-induced stimulation of cortisol and growth hormone secretion in chronic myeloproliferative syndrome

This study investigated the acute effects of interferon-alpha 2 (IFN-alpha 2) on hormonal secretion in adult patients affected by a chronic myeloproliferative syndrome and tried to shed some light on the mechanism by which IFN-alpha 2 stimulates cortisol and GH secretion in humans. We compared the pattern of IFN-alpha 2-induced cortisol and GH release with that elicited after the same challenge given subsequent to pretreatment with dexamethasone (Dex). We studied eight patients affected by a chronic myeloproliferative syndrome (thrombocythemia) who had been selected for treatment with IFN-alpha 2. Four sets of experiments were performed: 1) 2 mL iv saline was given at 0800 h in eight cases; 2) 3 x 10(6) IU iv IFN-alpha 2 was given at 0800 h in eight cases; 3) 3 x 10(6) IU iv IFN-alpha 2 was given at 0800 h after pretreatment with 1.5 mg Dex (1 mg at midnight the previous night and 0.5 mg at 0700 h on the day of the test) in six cases; and 4) 2 mL iv saline was given at 0800 h after the same Dex pretreatment in four cases. Cortisol and GH were measured in plasma samples drawn at 30-min intervals between 0800 and 1300 h. Acute iv administration of IFN-alpha 2 stimulated the release of both cortisol and GH in each patient with a significant increment vs. control values, as assessed by areas under the curve. The administration of Dex significantly decreased basal plasma cortisol secretion and abolished cortisol response to IFN-alpha 2 administration. These data suggest that the stimulatory action of IFN-alpha 2 on cortisol release is mediated via a modulation of the activity of the hypothalamic-pituitary axis rather than through a direct effect at the level of the adrenal cortex. After Dex plus saline administration, no significant effect was observed on plasma GH levels, which remained low. Dex administration significantly decreased GH response to IFN-alpha 2. These data suggest that a hypothalamic or pituitary stimulation (or both) is involved in the mechanism of IFN-alpha 2-induced GH secretion. It remains to be established whether IFN-alpha 2 directly stimulates pituitary somatotropic cells or whether the cytokine exerts a stimulatory action on GH secretion by indirectly modulating the hypothalamic or pituitary activity. In conclusion, acute iv administration of IFN-alpha 2 represents a potent stimulus for cortisol and GH secretion in adult human subjects.(ABSTRACT TRUNCATED AT 400 WORDS)     

Heterogeneity of the zona pellucida carbohydrate distribution in human oocytes failing to fertilize in vitro

The mammalian zona pellucida contains several glycoproteins whose oligosaccharide moieties are known to play a key role in the interaction with spermatozoa. Since zona pellucida defects may represent one of the most likely causes of failed fertilization in human in-vitro reproduction, we have studied the carbohydrate composition and distribution over the human zona pellucida by means of lectins. Donated, not inseminated cumulus-oocyte complexes, from cohorts with high fertilization rates, and fertilization-failed oocytes from cohorts inseminated with proven fertile donor semen, were analysed using 11 fluorescein-labelled lectins, on deplasticized semi-thin epoxy sections. Results showed that wheat germ agglutinin (WGA), Maclura pomifera (MPA) and Pisum sativum (PSA) bound to the extracellular matrix bordering the zona pellucida-corona radiata interface of cumulus-oocytes complexes, while the zona pellucida was labelled by WGA, Concanavalin A (ConA) and PSA. WGA labelling and correlative electron microscopy on the cumulus-oocyte complexes demonstrated that this lectin is a useful tool to trace the cortical granule distribution in the human oocyte. Surprisingly, in the failed-fertilized oocytes the zona pellucida was also labelled by MPA and showed three different patterns: (i) labelling of the zona pellucida outer surface; (ii) uniform labelling; (iii) labelling of an outer zona pellucida layer with variable thickness. Comparative analysis of WGA and MPA labelling on single failed-fertilized oocytes demonstrated that MPA zona pellucida patterns are not related to the cortical reaction. The nature and meaning of the MPA pattern of failed-fertilized oocytes were discussed in the light of zona pellucida defects impairing sperm receptivity.     

Toxin-producing Ostreopsis cf. ovata are likely to bloom undetected along coastal areas

Mass appearances of the toxic dinoflagellate genus Ostreopsis are known to cause dangerous respiratory symptoms in humans exposed to aerosols. The outbreaks can appear in shallow marine waters of temperate regions around the globe. We followed a massive bloom event on a public beach on the northern Adriatic coast near Rovinj, Croatia. We identified the responsible species and the produced toxins as well as the dynamics of the event with respect to environmental conditions. Ostreopsis cf. ovata appeared in masses from September through October 2010 on a public beach near Rovinj, Croatia but stayed undetected by public health organizations. Respiratory symptoms were observed whenever humans were exposed to substrate samples containing large numbers of Ostreopsis cells. During the mass abundance of O. cf. ovata also exposure to the aerosols on the beach evoked respiratory symptoms in humans. Our measurements showed high cell abundances and high toxin contents with a stable relative contribution of putative Palytoxin and Ovatoxins a-e. Artificial beach structures proved to dramatically reduce settling of the observed Ostreopsis biofilm. Blooms like those reported herein have a high potential to happen undetected with a high potential of affecting the health of coastal human populations. Increased monitoring efforts are therefore required to understand the ecology and toxicology of those bloom events and reduce their negative impact on coastal populations.     

Diagnostic Imaging Information Systems: DREAM. Reporting management

From the clinical standpoint, the report represents the synthesis of the diagnostic process and it is the central activity of radiology. However, reporting cannot be separated from the entire organizational cycle inside the Diagnostic Imaging Department as well as within the structure as a whole. The effectiveness of the contribution an information system can give to the radiologist is related to the information and functional integration of the various applications operating in the hospital and over the territory. Based on these considerations, the main types of support the information tool can offer, are reported together with the primary objectives which were basic to the development of the reporting module within the DREAM system and the major solutions adopted to facilitate the attainment of these objectives.     

Resolution Limits in the Fresnel Zone: Roles of Aperture and Frequency

The reconstruction of the dielectric permittivity profile from scattered field measurements in two dimensions is addressed in free space under the Born approximation. Canonical geometries suitable for future extensions to subsurface sensing configurations are dealt with. In particular, a rectilinear measurement aperture located in the Fresnel zone and rectilinear investigation domains parallel or orthogonal to the measurement line are considered for the scalar e.m. case. Firstly, the dependence of both transversal and longitudinal resolution on the geometrical parameters of the sensing configuration is analytically worked out in only aspect diversity. Then, the effect of frequency diversity on depth-resolution is also pointed out.     

In-depth resolution from multifrequency Born fields scattered by a dielectric strip in the Fresnel zone

The achievable depth resolution in reconstructing the permittivity profile of a dielectric strip under the Born approximation when data are collected in the Fresnel zone is studied. We consider a rectilinear measurement aperture and an orthogonal and centered rectilinear investigation domain. The roles of the aperture extent and frequency diversity are highlighted.     

Influence of temperature and salinity on Ostreopsis cf. ovata growth and evaluation of toxin content through HR LC-MS and biological assays

In the Mediterranean Sea, blooms of Ostreopsis cf. ovata and Ostreopsis siamensis have become increasingly frequent in the last decade and O. cf. ovata was found to produce palytoxin-like compounds (putative palytoxin, ovatoxin-a, -b, -c, -d and -e), a class of highly potent toxins. The environmental conditions seem to play a key role in influencing the abundance of Ostreopsis spp. High cell densities are generally recorded in concomitance with relatively high temperature and salinity and low hydrodynamics conditions. In this study the effects of temperature and salinity on the growth and toxicity of an Adriatic O. cf. ovata isolate were investigated. The highest growth rates of the Adriatic strain were recorded for cultures grown at 20 °C and at salinity values of 36 and 40, in accordance with natural bloom surveys. Toxicity was affected by growth conditions, with the highest toxin content on a per cell basis being measured at 25 °C and salinity 32.However, the highest total toxin content on a per litre basis was recorded at 20 °C and salinity 36, since under such conditions the growth yield was the highest.O. cf. ovata had lethal effects on Artemia nauplii and juvenile sea basses, and produced haemolysis of sheep erythrocytes. A comparison between haemolysis neutralization assay and HR LC-MS results showed a good correlation between haemolytic effect and total toxin content measured through HR LC-MS. Considering the increasing need for rapid and sensitive methods to detect palytoxin in natural samples, the haemolytic assay appears a useful method for preliminary quantification of the whole of palytoxin-like compounds in algal extracts.     

Detection of thermal-induced prompt fission neutrons of highly-enriched uranium: A position sensitive technique

Cargo interrogation in search for special nuclear materials like highly-enriched uranium or ²³⁹Pu is a first priority issue of international borders security. In this work we present a thermal-pulsed neutron-based approach to a technique which combines the time-of-flight method and demonstrates a capability to detect small quantities of highly-enriched uranium shielded with high or low Z materials providing, in addition, a manner to know the approximate position of the searched material.     

The Genoa 2005 outbreak. Determination of putative palytoxin in Mediterranean Ostreopsis ovata by a new liquid chromatography tandem mass spectrometry method

A new method for sensitive, specific, and direct determination of palytoxin is proposed herein. It is based on combination of reversed-phase liquid chromatography with mass spectrometry (LC-MS). The new method was set up on a turbo ion spray-triple quadrupole MS instrument operating in selected ion monitoring (SIM) and multiple reaction monitoring (MRM) acquisition modes (positive ions). The minimum detection levels for matrix-free toxin on column were thus estimated from the data to be 200 and 125 pg in SIM and MRM modes, respectively. Spiking experiments before and after extraction allowed us to assess limits of detection and quantitation for palytoxin in matrix, accuracy, and intraday and interday reproducibility of the method. The developed method was decisive for the analysis of a plankton sample collected along Genoa coasts in July 2005 when respiratory illness in people exposed to marine aerosols occurred. It is suggested that putative palytoxin was the causative agent responsible for patients' symptoms and demonstrated for the first time the presence of such a toxin in Italian waters.