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The NA48/2 experiment collected data in 2003 and 2004 with the main purpose to study direct CP violation in charged kaons decaying in three pions. Thanks to the huge statistics collected, other studies are also possible. In this paper two recent results, in the framework of QCD studies, are reported: the measurement of the K±→ π0e±νForm Factors and the first observation of the rare decay K±→ π±π0e+e−.

The mechanical behavior of the pseudoelastic cycles in CuZnA1 single crystals, at temperatures higher than room temperature, is affected by the occurrence of diffusive phenomena. Conversely, the diffusive phenomena are altered when defects are formed during cycling. In the present work we analyze the effects of pseudoelastic fatigue on the mechanical behavior. A critical step in the analysis is the definition of a reference state in order to quantify the further evolutions. Results show how this reference state depends on the test temperature, and in which way this fact must be considered if the mechanical evolution of the material is analyzed. Recently it has been shown how the characteristics of the diffusion related processes under static conditions are altered after cycling. In this work an upper limit temperature for this effect is presented. As an example, the stabilization of martensite under non dynamic conditions (static stabilization) was found to be significantly reduced after cycling at 333 K but shows no changes at 376 K. The range of temperatures at which this phenomena is present is then determined. The effect of the stabilization due to the equilibrium concentration of vacancies, and their interaction with bulk defects, is considered in order to improve the comprehension of different contributions to the mechanical behavior.

Previous studies have shown that pseudoelastic cycling of Cu-Zn-Al single crystals leads to surface and bulk defects with consequences on the mechanical behavior and fracture properties of these alloys. Recently it has been shown that the number of cycles to nucleate surface defects depends on the composition of the alloy. In this work we have carried out in-situ tensile cycling experiments under direct observation by scanning electron and optical microscopy. The attention was focused on single crystals with an electron concentration of 1.43. We found strong correlation between the dynamics of the transformation-retransformation cycles and the surface and bulk defects, which form aligned with the trace of the habit plane and the basal plane of the induced martensite. In addition, the orientation of the tensile axis was found to be an important parameter concerning the morphology of the surface defects. Transmission electron microscopy studies have been performed to complete the characterization of defects.

Effects of new physics in flavor could be found both in Flavor Changing Neutral Current (FCNC) processes and in Lepton Flavor Violation (LFV) modes. The former offer the possibility to deeply test the standard model in a clean environment, while the latter are sensitive to contribution from several models beyond the standard model. In the Kaon sector both FCNC and LFV will be investigated in the NA62 experiment. In addition the kaons sector is an ideal place where to look for new particles and tiny effects, in the region of hundreds of MeV/c2. In this paper prospects for exotic searches in NA62 will be presented, together with recent results from NA48/2 and NA62-RK on LFV kaon decays modes.

Abstract: From time immemorial men have strived to measure the size of celestial bodies. Among them, the diameter of the Sun was a source of curiosity and study. Tackled by Greek astronomers from a geometric point of view, an estimate, although incorrect, has been first determined, not truly called into question for several centuries. One must wait up to the XVIIth century to get the first precise determinations made by the French school of astronomy. Gradually, as the techniques were more and more sophisticated, many other solar diameter measurements were carried out, notably in England, Germany, Italy and US. However, even with instruments at the cutting edge of progress, no absolute value of the solar diameter has been provided yet, even if the community has adopted a canonical radius of 959.″63, given in all ephemeris since the end of the XIXth century. One of the major difficulties is to define a correct solar diameter. Another issue is the possible temporal variability of the size of the Sun, as first advocated at the end of the XIXth century by the Italian school. Today, this question is just on the way to being solved in spite of considerable efforts developed on ground-based facilities or on board space experiments. We will here give a review of some of the most remarkable techniques used in the past, emphasising how incorrect measurements have driven new ideas, leading to develop new statements for the underlying physics. On such new grounds, it can be speculated that the roundness of the Sun is not perfect, but developing a thin “cantaloupe skin” in periods of higher activity, with departures from sphericity being inevitably bounded by a few kilometers (around 80 km or 10 to 15 mas).

Abstract: The story of the solar oblateness begins in the pre-relativity days when an explanation of the observed advance of Mercury’s perihelion was searched for. Then, examination of historical records during the first decade of the twentieth century shows clearly a strong effort to measure the solar shape. Results show discrepancies, due on one hand, to the fact that physical statements in the solar case are still pending (for example does the solar core rotate rapidly? Is the Sun an oblique rotator? How does the magnetic field distort the outer shape?) and on the other hand, due to the difficulty in measuring a faint quantity, even when using the cutting edge of up-to-date techniques. We provide a new perspective on the controversy which followed measurements made in Princeton (USA) in the mid-1960s, highlighting the possibility to advocate alternative theories of gravitation. Since then, the accurate shape of the Sun has been actively debated, and so far, only satellite experiments seem to achieve the required sensitivity to measure the expected faint deviations to sphericity. In a close cooperation between experiments and theory, we point out how false ideas or inexact past measurements may contribute to the advancement of new physical concepts.

Hybrid PhotoDiodes (HPDs) are very simple photo detectors which cover the applicability field of Photo Multipliers but show some better features. In particular HPDs show a very good photon counting capability, due to their peculiar one-stage gain process. It was found that HPD's photoelectron spectrum has a low-energy continuum which could be attributed to a backscattering process from the diode surface. In order to clearly distinguish the exact role of backscattering, the single photoelectron response (SER) of a 61 pixel proximity focused HPD was measured in standard conditions and in a 5 kG axial magnetic field. The results clearly indicate that the backscattering process gives the greatest contribution to the low-energy continuum spectrum. Monte Carlo simulations, using the EGS4 code, supported the analysis and allowed some interpretation of the effect, which greatly depends on diode surface characteristics, such as contact layer thickness.

Photodetection and photon imaging have always been an important tool for medical diagnosis, therapy and prognosis. Radiology and nuclear medicine are the two disciplines that have taken most advantage of the advent of new digital detector technology to improve their sensitivity and specificity. A brief overview will be given and selected new developments and new ideas will be discussed at length.

The influence of the absorption of hydrogen on the martensitic transformation of polycrystalline wires of a Ti–49.83at%Ni–0.08at%Cu alloy was studied using electrical resistivity. It was found that the stability of the austenite and the martensite is affected in the same way, resulting in no change of the transformation temperatures for H concentrations as high as 12 at%. No indication for hydrogen desorption was found below 423 K. Hydrogen has also been charged in single crystalline samples of three Cu–Zn–Al alloys at room temperature, presenting the β, 18R or 2H phases. The maximum concentration reached was around 0.04 at% and no influence was found on several properties of the martensitic transformation.

This paper is a review of the studies carried out at JRC Ispra on assembly and maintenance by remote handling of first wall and blanket, following the approach of coupling computer and experimental simulation. For this purpose, a CAD⁄CAE laboratory for computer simulation of teleoperation, TELEMAC, and an experimental heavy robotics facility, ROBERTINO, have been set up. This paper explains the reasons for using simulation equipment, subsidiary to the use of large prototype transporters, to contribute to the next step reactors design with reduced time and cost. Maintenance procedures can be simulated in a virtual environment, prior to their implementation on ROBERTINO, which allows experimental simulation on reduced or full scale simplified mock-ups. ROBERTINO can also be used for experimental validation of operations of general interest, performed by means of prototype tools. The paper reports the results of test campcugns carried out so far, in collaboration with ENEA, one concerning the simulation studies of whole blanket segments maintenance on reduced scale mockups and another concerning the experimental validation of pipes cutting⁄welding using bore tools (i.e. acting from inside the pipes). These results confirm the validity of the proposed approach. The paper shows how the JRC simulation equipment could be used to assess, on full size mock-ups, the feasibility of the blanket modules attachment to the back-plate, for any design concept following the evolution of the ITER project.

The remote replacement of blanket segments inside the vacuum vessel of a fusion reactor is probably the most complex task from the maintenance standpoint. Its success will rely on the definition of appropriate handling concepts and equipment, but also on a "maintenance friendly" reactor layout and blanket design. The key difficulty is the lack of rigidity of the segments which results in considerable deformations since they cannot be gripped above their centre of gravity. These deformations may be up to five times greater than the assembly clearance and one order of magnitude larger than the required positioning accuracy. Experimental activities have been undertaken to select appropriate handling devices and procedures, to assess the design of the components handled, and to review specific technical issues such as kinematics and dynamics performance, trajectory planning and control and sensors requirement for the handling devices. Work was performed in the Robertino facility where two handling concepts have been tested at a 1/3 scale.

This study was carried out in order to evaluate clinical usefulness of cross-linked N-telopeptides (NTx) of type I collagen determination, in patients with primary hyperparathyroidism. Twenty-six consecutive patients (6 males and 20 females, aged 56.3±15.0, SD, yrs) with primary hyperparathyroidism were studied in basal conditions and, ten of them, after surgical cure of the disease. Cross-linked collagen peptides were measured by enzyme-linked immunosorbent assay and conventional markers of bone turnover according to standard procedures. Bone densitometry at the lumbar spine and proximal femur was performed using dual-energy X-ray absorptiometry. Bone mineral density was also assessed at the junction of the distal and middle third of the radius and at the ultradistal radius of the non-dominant arm by a dual photon densitometer. Mean urinary NTx values (194.2±121.9 pmoles bone collagen equivalents/pinoles creatinine) were significantly higher (p<0.001) in respect to those found in normal subjects. The mean increase of Z score values of both serum tartrate resistant acid phosphatase activity (1.4±1.8) and the fasting hydroxyproline/creatinine ratio (1.45±2.0) was significantly lower (p<0.02) in respect to that of NTx Z score values (3.3±3.3); the latter values were not significantly different than mean Z score values of serum osteocalcin (4.0±3.9), serum alkaline phosphatase activity (2.6±2.6) and urinary calcium/creatinine ratio (3.2±3.3). We found a significant inverse correlation between NTx values and both lumbar spine (p<0.01) and ultradistal radius bone mineral density (p<0.05); a modest inverse correlation was also observed between serum tartrate resistant acid phosphatase activity and lumbar spine bone mineral density (p<0.04). Following successful adenoma removal, the percentage decrease of both NTx and hydroxyproline was similar in patients with increased bone turnover rate; major discrepancies were observed in patients with normal values of NTx, the telopeptide reduction being greater than that of hydroxyproline. Finally, in a hypercalcemic patient with metastatic parathyroid cancer, telopeptide excretion was shown to be more sensitive in respect to urinary hydroxyproline when evaluating the effects of antiresorptive therapy. Our results seem to indicate that amongst the markers with good sensitivity, NTx is the only one that is inversely related with bone mineral density at two different skeletal sites. This assay should therefore have a place in both the initial screening and medical follow-up of patients with this glandular disorder; in fact, in both situations an increased urinary excretion of this marker should warn about the possibility of hidden bone loss.

The purpose of the present study was to compare arterial pressure (AP) and heart rate (HR) responses to submaximal isokinetic, isotonic and isometric exercises currently employed in physical rehabilitation therapy in terms of both magnitude and time-course. To this aim AP and HR were continuously and noninvasively measured in ten healthy subjects performing isokinetic, isotonic and isometric exercises at the same relative intensity. Isokinetic and isotonic exercises consisted of 30 knee extension/flexion repetitions at 40% of maximal effort. Isokinetic speed was set at 180°?·?s -1. Isometric exercise consisted of a 60-s knee extension at 40% maximal voluntary contraction. The AP showed a rapid and marked increase from the onset of all types of exercise progressing throughout the exercises. Peak systolic (SAP) and diastolic (DAP) arterial pressure were 190.7 (SEM 8.9) and 121.6 (SEM 7.8) mmHg during isokinetic and 197.6 (SEM 11.2) and 128.3 (SEM 7.7) mmHg during isotonic exercise, respectively. During isometric exercise peak SAP and DAP were 168.1 (SEM 6.3) and 102.1 (SEM 3.7) mmHg, respectively [both lower compared to isokinetic and isotonic exercise ( P?-1, continuing to rise throughout the exercises. The HR response to isometric exercise was significantly less ( P?

La menstruación ha tenido diferentes significados en diversas culturas a lo largo de la historia. Desde Regnier de Graaf en el siglo xviihasta la fecha, pasando por la médica norteamericana Mary Putnam Jacobi a finales del sigloxix, un buen número de pioneros científicos estudiaron el sistema reproductor femenino con el fin de entender la fisiología del ciclo menstrual. En el Nuevo Reino de Granada, durante los siglos xviiiyxix, se desarrolló por parte de médicos y boticarios una receta médica a base de agentes herbarios y de origen animal con el fin de regular el ciclo menstrual, disminuyendo de esta forma síntomas asociados a esta condición para evitar el estigma sociocultural que esta condición implicaba para la mujer en aquel entonces. Esta receta se encuentra en la actualidad consignada en el archivo histórico Cipriano Rodríguez Santamaría en la biblioteca Octavio Arizmendi Posada de la Universidad de La Sabana en Chía, Colombia. La redacción y autoría de esta receta no es del todo clara, y su uso se basa eventualmente en la experiencia y observación de quienes en esa época la utilizaron, sin bases científicas para respaldar su eventual efecto modulador y terapéutico.

Context.Transiting planetary systems allow us to extract geometrical information, e.g., the angle ϵbetween the orbital angular momentum and the stellar spin, that can be used to discriminate among different formation and evolutionary scenarios. This angle is constrained by means of the Rossiter-McLaughlin effect observed on radial velocity and can be subject to large uncertainties, especially for hot stars (Teff> 6250 K). It is thus interesting to have an alternative method to constrain the value of the obliquity ϵand to detect companions that might have disturbed the orbit of the planet.

Context.Tidal dissipation in late-type stars is presently poorly understood and the study of planetary systems hosting hot Jupiters can provide new observational constraints to test proposed theories.