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We present new UBV I CCD observations of the old LMC globular cluster RETICULUM. These data allowed us to re-determine periods and light curves and to identify 4 double mode RR Lyrae stars. A comparison with the theoretical instability strip in the MV − logP plane shows good agreement between theory and observations when an apparent distance modulus of (m−M)=18.45±0.12 mag (i.e.(m−M)0=18.39±0.12 mag) is assumed.

Cardiotoxicity is a well-known adverse effect of various chemotherapeutic agents that can be monitored by echocardiography. A decrease of left ventricular ejection fraction (LVEF) during the therapy might indicate dangerous effects of the drug on the myocardium and triggers consideration of therapy modification or interruption. We hypothesized myocardial deformation could identify preclinical myocardial dysfunction earlier than conventional LVEF allowing the administration of treatments to avoid cardiac side-effects. Sixty-five patients who were newly diagnosed with breast cancer, were enrolled to be evaluated by echocardiography before cancer therapy, during the therapy at 16 weeks (16w) and at follow up after 32 weeks (32w). Following the recommendation, 24 patients (36.9%) showed cardiotoxicity; 11 (16.9%) interrupted the therapy due to a severe cardiac dysfunction and at 32w only 4 patients recovered. In this group at 16w, strain analysis showed a significant reduction for all strain values that were all predictive of cardiotoxicity independently from LVEF and radial strain resulted an independent prognostic index of cardiotoxicity. The assessment of myocardial deformation indexes might provide additional echocardiographic tools to assess cardio-toxic effects beyond LVEF. © 2013 CCAL.

Hernia repair is the most common surgical procedure in general surgery in Italy and in the Lombardy region. In the last decade, the use of mesh, the concept of a tension-free technique, and the postoperative rate of recurrences after Bassini or Shouldice operations have completely changed the surgical approach to hernia repair. For this reason, we sent a questionnaire to 148 surgical departments in the Lombardy region to investigate about total hernia operations performed in 2000 in Lombardy, the surgical approach, the surgical techniques used, the type of anesthesia and the hospital stay. One hundred five out of 148 surgical departments returned the questionnaire, and we collected information on a total of 16,935 surgical operations for hernia: 16,494 were performed using tension-free techniques. The inguinal anterior approach is the one of choice for primary and recurrent inguinal hernia, whereas the open preperitoneal and laparoscopic approaches are limited to bilateral and recurrent hernias. The majority of cases were treated under locoregional anesthesia and with a hospital stay of two nights.

We present the development and testing of a semi-automated tool to support the diagnosis of left ventricle (LV) dysfunctions from cardiac magnetic resonance (CMR). CMR short-axis images of the LVs were obtained in 15 patients and processed to detect endocardial and epicardial contours and compute volume, mass and regional wall motion (WM). Results were compared with those obtained from manual tracing by an expert cardiologist. Nearest neighbour tracking and finite-element theory were merged to calculate local myocardial strains and torsion. The method was tested on a virtual phantom, on a healthy LV and on two ischaemic LVs with different severity of the pathology. Automated analysis of CMR data was feasible in 13/15 patients: computed LV volumes and wall mass correlated well with manually extracted data. The detection of regional WM abnormalities showed good sensitivity (77.8%), specificity (85.1%) and accuracy (82%). On the virtual phantom, computed local strains differed by less than 14 per cent from the results of commercial finite-element solver. Strain calculation on the healthy LV showed uniform and synchronized circumferential strains, with peak shortening of about 20 per cent at end systole, progressively higher systolic wall thickening going from base to apex, and a 10° torsion. In the two pathological LVs, synchronicity and homogeneity were partially lost, anomalies being more evident for the more severely injured LV. Moreover, LV torsion was dramatically reduced. Preliminary testing confirmed the validity of our approach, which allowed for the fast analysis of LV function, even though future improvements are possible.

We have recently developed an automated technique using noise-based level-set methods and non-rigid registration for endocardial and epicardial border detection as a basis for perfusion quantification from cardiac magnetic resonance (CMR) images. The goal of the present work was to validate this technique against conventional manual analysis both directly and using quantitative coronary angiography as reference for significant disease (stenosis >50%). We studied 27 patients undergoing contrast-enhanced CMR imaging (1.5T) at rest and during adenosine stress. Contrast enhancement time-curves were constructed and used to calculate a number of perfusion indices. Measured segmental pixel intensities in each frame correlated highly with manual analysis (r=0.95). Bland-Altman analysis showed small biases (1.3 at rest; 0.0 at stress) and narrow limits of agreement (±13 at rest; ±14 at stress). The derived perfusion indices showed the same diagnostic accuracy as manual analysis (AUC up to 0.72 vs. 0.73). These results indicate that our automated technique allows fast detection of myocardial ROIs and quantification of stress-induced perfusion abnormalities as accurately as manual analysis.

Background/Aims: Total renal volume (TRV) is an important index to evaluate the progression of autosomal-dominant polycystic kidney disease (ADPKD). TRV has been assessed by manually tracing renal contours from CT or MR scans, often employing contrast medium (CM). We developed a fast and nearly automated technique based on the analysis of MR images acquired without CM injection for TRV quantification. Methods: 30 ADPKD patients underwent MRI. After the selection of one point inside each kidney for the entire volume, the automatic extraction of kidney contours was performed on each acquired slice; the segmentation procedure was based on region growing and on the application of morphological operators and curvature-based motion. The area inside each contour was calculated and TRV was derived. Volume measurements were validated by comparison with measurements obtained by stereology. Results: TRV estimated in patients was 768 ± 545 ml (range 161–3,111 ml). The automatic measurements were in excellent correlation with the manual ones (r = 0.99, y = x – 0.7), with a small bias and narrow limits of agreement in both absolute (–5 ± 37 ml) and percentage (–0.6 ± 9.6%) terms. Conclusion: This preliminary study showed the feasibility of a fast and nearly automated method for determining TRV; importantly it does not require the use of potentially nephrotoxic CM.

The left ventricle (LV) has been widely studied and many segmentation methods have been proposed allowing accurate volume estimation from cardiac magnetic resonance imaging (CMRI). Anatomical complexity of the right ventricle (RV) has made accurate determination of RV shape and volume difficult. We propose a fully automated method for both RV and LV segmentation from CMRI. Datasets were analysed using custom software based on a region-based level set model followed by a regularization motion, allowing dynamic endocardial contour detection. RV and LV contours were also manually traced at end-diastole (ED) and end-systole (ES). For both techniques, disk-area summation method was applied to compute volumes. Volumes at ED and ES and ejection fraction were compared. The results of this initial study provide the basis for automated, fast and accurate quantification of LV and RV size, function and volume change throughout the cardiac cycle.

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This special issue of the Journal of Modern Optics contains extended versions of selected papers accepted and presented at the 10th International Workshop on Advanced Infrared Technology and Applications held on 8-11 September 2009 at the Astronomy and Space Science Department of the University of Florence, Italy. The workshop - an event in a biennial series of meetings that started in 1991, and organised by Fondazione 'Giorgio Ronchi' (Florence), the Institutes of Information Science and Technologies 'Alessandro Faedo' (Pisa), Construction Technologies (Padova), Applied Physics 'Nello Carrara' (Florence) of the Italian National Research Council and the CREO Consortium, L'Aquila - constitutes a forum for bringing together academic and industrial researchers to exchange knowledge, ideas and experiences in the field of infrared (IR) science and technology. The main topics of the workshop included, in particular, advanced technology and materials, smart and fibre-optic sensors, aerospace and industrial applications, astronomy and earth monitoring, nondestructive tests and evaluation, systems for cultural heritage, near-, mid-, and long-wavelength systems, and image processing and data analysis. This special issue includes 17 papers that discuss scientific and technological aspects related to a few of these areas.

We report the experimental measurement of Ramsey interference fringes in the single-photon excitation to a high-lying bound state of atomic argon by pairs of phase-locked, time-delayed, extreme UV high-order harmonic pulses at 87 nm. High-visibility Ramsey fringes are observed for delays larger than 100 ps, thus demonstrating a potential resolving power >10^5 at this wavelength.

The aim of this study was to gain a wide perspective of the arrhythmogenic right ventricular dysplasia (ARVD) by developing algorithms for Cardiac Magnetic Resonance Imaging. We developed a semi-automatic procedure to assess the Right Ventricle (RV) volumes and to quantify RV wall motion; moreover, with the increased visible details in a single MR image, a manual method to evaluate the trabeculae mass was performed. All the algorithms used were based on the level set theory which allows detecting both endocardial and wall surfaces, as well as the black parts characterizing the trabeculae. 6 normal subjects and 6 subjects with ARVD heve been investigated. Our method and the standard manual method for volume estimation were significantly correlated (y=0.92x+6.56), (r=0.92 p

Mitral valve (MV) repair is the preferred treatment for mitral regurgitation associated with organic MV prolapse (MVP). Our goal was to describe the dynamic changes in mitral annulus (MA) geometry after annuloplasty, using custom software for MA tracking from transthoracic real-time 3D echocardiography (RT3DE). Forty-four MVP patients, divided into 2 subgroups (RIG and FLEX), were studied by RT3DE the day before, at 3 and 6 months after surgery. RT3DE was also obtained in 20 normal (NL) subjects. MA was tracked frame-by-frame and several parameters were computed. As expected, MVP had an enlarged MA and a reduced planarity compared to NL. Annuloplasty resulted in reduced area both in RIG and FLEX and in a more planar MA shape. Interestingly, at 3 and 6 months, FLEX height was greater than RIG, due to different ring design. This analysis gives new insights in the in-vivo performance of the implanted rings, offering a new tool in the clinical decision process and follow-up.

We report the experimental observation of an enhancement in the yield of high-order harmonics using an array of gas jets as the source medium. By comparing the experimental outcome for jet arrays of different spacings with the predicted harmonic intensity in the case of slit sources of equivalent lengths, we clearly show how the periodic modulation of the gas density can improve the harmonic yield. This behavior may be attributed to a quasi-phase-matching effect which increases the length of coherent harmonic buildup during propagation by partially counteracting the dephasing induced by free electrons

BACKGROUND: High-throughput molecular biology provides new data at an incredible rate, so that the increase in the size of biological databanks is enormous and very rapid. This scenario generates severe problems not only at indexing time, where suitable algorithmic techniques for data indexing and retrieval are required, but also at query time, since a user query may produce such a large set of results that their browsing and "understanding" becomes humanly impractical. This problem is well known to the Web community, where a new generation of Web search engines is being developed, like Vivisimo. These tools organize on-the-fly the results of a user query in a hierarchy of labeled folders that ease their browsing and knowledge extraction. We investigate this approach on biological data, and propose the so called The BioPrompt-boxsoftware system which deploys ontology-driven clustering strategies for making the searching process of biologists more efficient and effective. RESULTS: The BioPrompt-box (Bpb) defines a document as a biological sequence plus its associated meta-data taken from the underneath databank--like references to ontologies or to external databanks, and plain texts as comments of researchers and (title, abstracts or even body of) papers. Bpboffers several tools to customize the search and the clustering process over its indexed documents. The user can search a set of keywords within a specific field of the document schema, or can execute Blastto find documents relative to homologue sequences. In both cases the search task returns a set of documents (hits) which constitute the answer to the user query. Since the number of hits may be large, Bpbclusters them into groups of homogenous content, organized as a hierarchy of labeled clusters. The user can actually choose among several ontology-based hierarchical clustering strategies, each offering a different "view" of the returned hits. Bpbcomputes these views by exploiting the meta-data present within the retrieved documents such as the references to Gene Ontology, the taxonomy lineage, the organism and the keywords. Of course, the approach is flexible enough to leave room for future additions of other meta-information. The ultimate goal of the clustering process is to provide the user with several different readings of the (maybe numerous) query results and show possible hidden correlations among them, thus improving their browsing and understanding. CONCLUSION: Bpb is a powerful search engine that makes it very easy to perform complex queries over the indexed databanks (currently only UNIPROT is considered). The ontology-based clustering approach is efficient and effective, and could thus be applied successfully to larger databanks, like GenBank or EMBL.