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Muon radiography, also known as muography, is an imaging technique that provides information on the mass density distribution inside large objects. Muons are naturally produced in the interactions of cosmic rays in the Earth’s atmosphere. The physical process exploited by muography is the attenuation of the muon flux, that depends on the thickness and density of matter that muons cross in the course of their trajectory. A particle detector with tracking capability allows the measurement of the muons flux as a function of the muon direction. The comparison of the measured muon flux with the expected one gives information on the distribution of the density of matter, in particular, on the presence of cavities. In this article, the measurement performed at Mt. Echia in Naples (Saracino 2017 Sci. Rep. 7, 1181. (doi:10.1038/s41598-017-01277-3)), will be discussed as a practical example of the possible application of muography in archaeology and civil engineering [ABSTRACT FROM AUTHOR]

Muons of cosmic origin have a great capability to penetrate through matter. This property is exploited in muon radiography, also known as muography , a technique which allows to highlight the presence of discontinuities of the mass density in the subsoil such as cavities, tunnels or rock masses. A detector of cylindrical geometry, optimized for borehole studies and with a diameter of 24 cm, was developed and tested. The scintillation light is read out by 384 Silicon Photomultipliers, directly coupled to the bars. The front-end and acquisition electronics, entirely housed inside the detector, are based on the EASIROC chip and are characterized by limited energy consumption (about 30 W for the entire detector). The detector has been designed in such a way as to simplify its construction as much as possible for its eventual mass production. In this article some details concerning the construction and preliminary results of measurements conducted in the Mt Echia (Naples, Italy) underground are presented. [ABSTRACT FROM AUTHOR]

Objective: In patients with ischemic mitral regurgitation (IMR), we assessed dynamic changes in mitral annular geometry and motion during the cardiac cycle, and examined their association with the severity of IMR, using our computerized three-dimensional (3D) echo method. Methods: Real-time 3D echo was performed in 12 normal controls and 25 patients with IMR. The saddle-shaped annulus was reconstructed in every 3D volume/frame during a cardiac cycle. For each 3D volume/frame, we assessed the mitral annular area (MAA) and the annular contraction that was expressed as the percentage of the largest MAA accounted for by the change in MAA from largest to smallest calculated value. Results: In IMR patients, the minimum MAA occurred in late-systole, while it occurred in early-systole in the controls. IMR patients had a larger minimum MAA (6.7 ± 1.3 vs. 3.6 ± 0.8 cm, P < 0.001) and reduced annular contraction (23.0 ± 6.5 vs. 42.6 ± 7.0%, P < 0.001) when compared to controls. Both minimum MAA and annular contraction had significant correlations with IMR severity (r = 0.67 and r = 0.78, P < 0.001 for both). Conclusion: The contraction of the dilated mitral annulus occurred in late-systole in patients with IMR. The alterations of annular geometry and motion may be associated with the development of IMR. (Echocardiography 2010;27:1069-1077) [ABSTRACT FROM AUTHOR]

Summary:Pharmacokinetic and clinical outcome measures among three groups of patients undergoing hematopoietic transplant were assessed: group A: Parenteral busulfan (Bu) 3.2?mg/kg i.v. given qd, n=20; group B: parenteral Bu 0.8?mg/kg i.v. given every 6?h, n=11; group C: Bu 1?mg/kg p.o. given every 6?h, n=25. All groups received Bu over 4 days followed by Cy 60?mg/kg i.v. qd over 2 days; followed by an infusion of allogeneic stem cells. Median Bu clearance was 3.21?ml/min/kg and median daily AUC was 4071?µmol/min for the group A patients. The dosing formula for Bu i.v. qd was highly predictive of the AUC for patients whose mass?IBW+20%. For patients of greater mass, the dosing formula uniformly resulted in lower-than-predicted AUC. Neurologic toxicity, hepatic toxicity, hematologic engraftment, and relapse at 100 days were comparable across all three groups. Severe AGVHD was least among group A, followed by group B when compared with group C. Bu i.v. qd is a safe and effective regimen for allogeneic transplantation and is at least clinically equivalent to every 6?h dosing schemes using either oral or parenteral Bu.Bone Marrow Transplantation (2005) 35, 747-754. doi:10.1038/sj.bmt.1704871 Published online 7 March 2005 [ABSTRACT FROM AUTHOR]

The High-Intensity Kaon Experiment (HIKE) is a proposed future kaon experiment designed for the CERN SPS accelerator. To cope with a planned increase of beam intensity by a factor of 4 with respect to the current NA62 experiment, the new Main Electromagnetic Calorimeter (MEC) has to provide a similar improvement in time resolution over the current Liquid Krypton calorimeter, down to ≈ 100 ps for a 40 GeV photon, while maintaining a comparable energy and spatial resolution. To achieve these goals, the planned detector consists of a shashlik calorimeter paired with high-resolution analog to digital converter for both energy deposit and arrival time estimates, operating at fast sample rates (∼ 1 GHz). This contribution describes a prototype of the readout system using commercial "off-the-shelf" boards. In particular, we focused on feature extraction and tested it using a pulse generator. We included a data readout logic based on the TCP/IP protocol allows for easy deployment in beam tests. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the effects of an educational intervention on physicians' management of low back pain patients. The study universe composed of 64 providers employed by a large occupational health group, with 4411 LBP cases pretraining and 4665 cases posttraining selected from the organization's database. The control group had 151 providers with 8478 pretraining and 8876 posttraining cases. Results showed that practices of physicians who participated in the intervention strategy underwent significant changes between the two intervals. Specifically, the intervention group reduced the percentage of restricted work cases, reduced the percentage of lost-time cases for male patients and female patients (less than 40 years old), and shortened restricted workday duration and total case duration for female patients. These results provide early indication for the effectiveness of this type of educational intervention strategy. [ABSTRACT FROM AUTHOR]

Muon radiography is a methodology which enables measuring the mass distribution within large objects. It exploits the abundant flux of cosmic muons and uses detectors with different technologies depending on the application. As the sensitive surface and geometric acceptance are two fundamental parameters for increasing the collection of muons, the optimization of the detectors is very significant. Here we show a potentially innovative detector of size and shape suitable to be inserted inside a borehole, that optimizes the sensitive area and maximizes the angular acceptance thanks to its cylindrical geometry obtained using plastic arc-shaped scintillators. Good spatial resolution is obtained with a reasonable number of channels. The dimensions of the detector make it ideal for use in 25 cm diameter wells. Detailed simulations based on Monte Carlo methods show great cavity detection capability. The detector has been tested in the laboratory, achieving overall excellent performance. [ABSTRACT FROM AUTHOR]

A novel algorithm developed within muon radiography to localize objects or cavities hidden inside large material volumes was recently proposed by some of the authors (Bonechi et al. 2015 J. Instrum. 10, P02003 (doi:10.1088/1748-0221/10/02/P02003)). The algorithm, based on muon back projection, helps to estimate the three-dimensional position and the transverse extension of detected objects without the need for measurements from different points of view, which would be required to make a triangulation. This algorithm can now be tested owing to the availability of real data collected both in laboratory tests and from real-world measurements. The methodology and some test results are presented in this paper [ABSTRACT FROM AUTHOR]

Abstract: Methods: We reviewed our prospectively maintained database of 2005 liver transplantations. Therapy was either started de novo or converted from calcineurin inhibitors (CNIs) to sirolimus as the main immunosuppressive agent for nephrotoxicity or rejection. Glomerular filtration rate (GFR) was determined with iodine 125–labeled sodium isthalamate (Glofil-125), and serum creatinine concentration was obtained before and 3 months after transplantation, and yearly in both groups. Sirolimus levels were 10 to 15 ng/mL in patients at less than 3 months after transplantations and 5 to 10 ng/mL in the remaining patients. All patients received mycophenolate mofetil as maintenance therapy. Results: Data for 29 patients in the de novo group and 35 in the conversion group were reviewed. Patients in the de novo group demonstrated an acute cellular rejection rate of 17.2%, 40% of which were steroid resistant. In this group, 48.2% discontinuation of sirolimus was necessary because of adverse effects. Patients in the conversion group demonstrated an acute cellular rejection rate of 2.8% and a 34.3% rate of sirolimus discontinuation. Seventeen (56.7%) patients at 1 year and 8 (44.4%) patients at 2 years demonstrated continued improvement in GFR. In the conversion group, case-control analysis did not demonstrate a significant difference in GFR and serum creatinine concentration (P > .05) at 1 and 2 years after conversion. At the time of review, no patients in the conversion group required hemodialysis. Conclusions: Conversion to sirolimus therapy is an effective strategy in improving renal function in patients with CNI-induced nephrotoxicity and can be done without increased rejection. Most of our patients (65.7%) tolerated sirolimus conversion. Of these, 56.7% and 44.4% demonstrated continued increase in GFR with the CNI-free regimen at 1 and 2 years, respectively. Long-term, large-population, prospective, randomized, controlled studies should further validate these results. [Copyright &y& Elsevier]

Applications of cosmic-ray muons have grown in numbers in the last decades. This was possible thanks to the development of detectors and techniques employed in particle and nuclear physics. Indeed the first famous application, the scanning of the Chephren's pyramid, was performed by L. W. Alvarez, that was a great expert in particle detectors and indeed was awarded a Nobel prize for his work on the hydrogen bubble chambers. After a first period in which the applications exploited mainly the absorption of the cosmic-ray muons when crossing a structure under investigation, more recently also the deflection of the muons has been used to design new applications. Nowadays more and more groups around the world are working on this research field. In the present review, after an introduction on cosmic-ray muons, the principles of the interaction of muons with matter will be briefly summarised. This description is important to classify the applications in three main categories: muon radiography , muon tomography and muon metrology. In the following, for each class, an overview of the basic ideas and a detailed description of the technologies will be presented along with a list of past and present applications. [ABSTRACT FROM AUTHOR]