Source Term and Mobilization Assessment in NSSR-1 of ITER

We describe the radioactive sources in the International Thermonuclear Experimental Reactor (ITER). The most important sources are co-deposited tritium, tritiated water, tokamak dust, and corrosion products. The co-deposited tritium is limited to 1 kg-T; the total on-site tritium inventory in the Basic Performance Phase (BPP) is 4 kg-T. Tritiated water concentrations are kept below 0.2 g-T/m³ in the divertor; other coolant loops have lower tritium concentrations. The in-vessel dust inventory is up to 100 kg-W, 100 kg-Be, and 200 kg-C. The activated corrosion product inventory is kept below 10 kg per loop.     

Extracorporeal lithotripsy in patients with acquired or congenital coagulopathies

Post ESWL haemorragic complications are frequent and most patients experience temporary haematuria and focal intrarenal bleeding or perirenal haematoma are detected by NMR or US imaging. By tradition coagulation troubles have been a contraindication for ESWL but literature describes cases of coagulopathic patients treated with ESWL. From January 1992 to July 1993, 4 of our patients with severe haemostatis troubles (severe haemophilia A in two cases, acquired deficit of coagulation factors and mild thrombocytopenia secondary to post-necrotic hepatitis in 1 case and Glanzmann's thrombasthenia in 1 case) underwent ESWL using Dornier HM3 mod. or MPL 9000. An extensive haematological and clinical evaluation pre and post-ESWL with an adequate haematological prophylaxis (transfusion of blood derivatives) has been performed depending on the coagulation disorder. In our patients we did not observe any haemorragic complication and we propose a reappraisal of the contraindications of ESWL in subjects with coagulation disorders: careful evaluation of haemorragic risk factors, by suitable correction measures and close clinical and instrumental monitoring, allows a reduction of the risk of haemorragic complications in coagulopathic patients who undergo ESWL treatment.     

RDX Detection with THz Spectroscopy

Spectroscopic analysis in the Terahertz frequency range, providing characteristic “signatures” for explosive and non-explosive materials, is proposed as an efficient and powerful tool for explosive identification. It is demonstrated that spectral responses of materials can be used as fingerprints that distinguish cyclotrimethylenetrinitramine (RDX) from other materials even with simple detectors and a limited number of available frequencies. Detection is performed using a modified least squares approach and multilayer perceptrons that operate on smoothed reflectance spectra. The performance of the detectors is evaluated through application to spectra of RDX and several common materials. A Receiver Operating Characteristic curve analysis demonstrates that our detectors exhibit the desirable properties of high probability of detection and low probability of false alarm.     

Non-contact atomic force microscopy study of hydroxyl groups on the spinel MgAl2O4(100) surface

Atom-resolved non-contact atomic force microscopy (NC-AFM) studies of the magnesium aluminate (MgAl(2)O(4)) surface have revealed that, contrary to expectations, the (100) surface is terminated by an aluminum and oxygen layer. Theoretical studies have suggested that hydrogen plays a strong role in stabilizing this surface through the formation of surface hydroxyl groups, but the previous studies did not discuss in depth the possible H configurations, the diffusion behaviour of hydrogen atoms and how the signature of adsorbed H is reflected in atom-resolved NC-AFM images. In this work, we combine first principles calculations with simulated and experimental NC-AFM images to investigate the role of hydrogen on the MgAl(2)O(4)(100) surface. By means of surface energy calculations based on density functional theory, we show that the presence of hydrogen adsorbed on the surface as hydroxyl groups is strongly predicted by surface stability considerations at all relevant partial pressures of H(2) and O(2). We then address the question of how such adsorbed hydrogen atoms are reflected in simulated NC-AFM images for the most stable surface hydroxyl groups, and compare with experimental atom-resolved NC-AFM data. In the appendices we provide details of the methods used to simulate NC-AFM using first principles methods and a virtual AFM.     

Review of Moisture and Liquid Detection and Mapping using Terahertz Imaging

The relatively high permittivity of liquid water compared to other materials in the Terahertz (THz) range enables a contrast mechanism for the detection and imaging of moisture. In this paper, spatial mapping of moisture and liquid detection by THz imaging is reviewed. Analysis of the moisture content is discussed in terms of a double Debye model for liquid water and effective medium models for the permittivity of the dry and ‘wet’ materials of interest. Examples from medical applications, forestry products, agriculture/ food products, and polymers are reviewed. Extraction of diffusion rates and diffusion maps from THz images are discussed.     

Web popularity: an illusory perception of a qualitative order in information

Using a psychotechnological perspective, this study discusses the current model of information ranking by search engines, based on quantitative Web Popularity (WP), which binds users to a cognitive adaptation to the rank-system restrictions. This phenomenon gives rise to a “rich-get-richer” effect on the Web. This paper claims that such an effect could be limited or reversed by the introduction of quality factors in ranking, and addresses the case of accessibility as a fundamental such factor. A study is reported which, through introducing an accessibility factor in a well-known popularity ranking algorithm, demonstrates that this transformation allows a qualitative rearrangement, without modifying or weighing on the properties of the rank. The overall approach is grounded on two development factors: the analysis of accessibility through specific tools and the employment of this analysis within all components used to build up the ranking. The results show that it is important to reconsider WP as including not only on the number of inbound and outbound links of a website, but also on its level of accessibility for all users, and on users’ judgment of the website use as efficient, effective, and satisfactory.     

Influence of refractive-index mismatch in high-resolution three-dimensional confocal microscopy

The effects of the refractive-index mismatch in confocal laser scanning microscopy were extensively studied. The axial aberration induced in the case of fluorescent microspheres was measured. The data were used to take into account the mismatch-induced aberrations and to consider object-size influence. Then we focused on the effect of refractive-index mismatch on the effective system's point-spread function under different mismatch conditions and on depth of focusing. We experimentally verified that the peak of the point-spread function intensity profile decreases and the point-spread function itself progressively broadens as a function of the combined effect of the refractive-index mismatch and of the penetration depth, leading to a worsening of the system's overall performances. We also performed these same measurements by embedding subresolution beads in an oocyte's cytoplasm, which can be considered a turbid medium. We found evidence consistent with the previously developed theoretical model; in particular we found a strong dependence of the intensity peak on the focusing depth.