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The Divertor Tokamak Test (DTT) facility [1], whose construction is starting in Frascati, will require robust and reliable diagnostics for the correct operation of the machine and the characterization of the plasma discharge. For this purpose, we are studying a common-path dispersion interferometer/polarimeter for the detection of plasma electron density and magnetic field in two different tangential chords in the equatorial plane. The physical principle is based on the generation of a second harmonic which crosses the plasma collinearly with the beam at its fundamental. Being the plasma a dispersive medium, the two beams are subject to different phase shifts from which it is possible to retrieve the plasma free electron density. Moreover, the unconverted part of the fundamental can be used for polarimetric measurement. Two different implementations of the interferometer have been considered, one with a CO2 laser (λ = 10.6/5.3 µm) and another one with Nd:YAG (λ = 1.064/0.536 µm). The former is more sensitive to lower plasma densities and to Faraday rotation, while the latter is more robust to fringe jumps. We have studied the main aspects of these two possible solutions. In particular, we analysed the optics to be used and the expected maximum signals for the interferometry and the polarimetry in a possible plasma scenario of DTT. A tentative draft of the layout of the optics inside the machine will be also presented.

A multi-channels poloidal interferometer/polarimeter is under development for the Divertor Tokamak Test (DTT) facility, a new tokamak device whose construction is starting in Italy. The aim of the diagnostics is the simultaneous measurement of the line integrated electron density, Faraday rotation and Cotton Mouton effect. The measurement of two polarimetric signals together with the interferometric one would allow for a robust electron density estimate, for the internal magnetic field measurement as well as for the magnetic equilibrium reconstruction. In this work, we present the advances in the diagnostics design whose characteristics are constrained by scientific requirements as well as the DTT structural aspects. In this regards, we have analyzed the possibility of accommodating up to 16 lines of sight in the available space and the contribution of different chords positions in the magnetic equilibrium reconstruction. In particular, we have used the VMEC and V3FIT codes to evaluate the expected interferometric/polarimetric signals and their contribution in the reconstruction of the q profile. These results have been used to optimize the chords positions. Eventually, we present a realistic CAD-driven design of the diagnostic, with details of the most critical components (e.g. the corner cube retroreflectors in the high field side), which would allow for the selected chords configurations implementation.

In order to translate the FLASH effect in clinical use and to treat deep tumors, Very High Electron Energy irradiations could represent a valid technique. Here, we address the main issues in the design of a VHEE FLASH machine. We present preliminary results for a compact C-band system aiming to reach a high accelerating gradient and high current necessary to deliver a Ultra High Dose Rate with a beam pulse duration of 3μs.The proposed system is composed by low energy high current injector linac followed by a high acceleration gradient structure able to reach 60-160 MeV energy range. To obtain the maximum energy, an energy pulse compressor options is considered. CST code was used to define the specifications RF parameters of the linac. To optimize the accelerated current and therefore the delivered dose, beam dynamics simulations was performed using TSTEP and ASTRA codes.The VHEE parameters Linac suitable to satisfy FLASH criteria were simulated. Preliminary results allow to obtain a maximum energy of 160 MeV, with a peak current of 200 mA, which corresponds to a charge of 600 nC.A promising preliminary design of VHEE linac for FLASH RT has been performed. Supplementary studies are on going to complete the characterization of the machine and to manufacture and test the RF prototypes.

A new source for the TANDEM accelerator of LNS has been designed and installed. It is called NESTOR (Noble Elements Source for acceleraTORs) and consists of an ultra-compact ECR microwave discharge type ion source [1] operating around 6 GHz and up to 40 W of RF power, provided by a solid state power amplifier, coupled to a Li-Charge Exchange Cell (Li-CEC). It is engineered for the production of a wide range of 1+ and/or 1- ion beams from gaseous elements, in particular for noble gases. This work presents the characterization of the primary source and first operations of the whole setup on the HV platform (injector) of the Tandem. The He+ beams have been formerly characterized in terms of current, beam shape (by BaF2 beam viewers) and emittance (by the three-gradients method). Measurements have been carried out varying pressure, microwave frequency and RF power. Then, the source has been moved to the HV platform, coupled to the Li-CEC for first operations running in gas-exchange mode. Activities are ongoing to optimize beam transport towards the Tandem.

We hereby report a study on confinement and electron loss dynamics in the magnetic trap of an electron cyclotron resonance ion source using a special multi-diagnostic setup that has allowed the simultaneous collection of plasma radio-self-emission and x-ray images in the range 500 eV–20 keV. Argon plasmas were generated in single- and two-close-frequency heating (SFH and TCFH) modes. Evidence of turbulent regimes has been found: for stable and unstable configurations quantitative characterizations of the plasma radio self-emission have been carried out, then compared with local measurements of plasma energy content evaluated by x-ray imaging. This imaging method is the only one able to clearly separate x-ray radiation coming from the plasma from that coming from the plasma chamber walls. X-ray imaging has also been supported and benchmarked by volumetric spectroscopy performed via silicon drift and high-purity germanium detectors. The obtained results in terms of x-ray intensity signal coming from the plasma core and from the plasma chamber walls permit the estimation of the average ratio: plasma vs. walls (i.e. plasma losses) as a function of input RF power and pumping wave frequency, showing an evident increase (above the experimental errors) of the intensity in the 2–20 keV energy range due to the plasma losses in the case of unstable plasma. This ratio was well correlated with the strength of the instabilities, in SFH operation mode; in TCFH mode, under specific power balance conditions and frequency combinations, it was possible to damp the instabilities, and thus the plasma losses were observed to decrease and a general reconfiguration of the spatial plasma structure occurred (the x-ray emission was more concentrated in the center of the plasma chamber). Finally, a simplified model was used to simulate electron heating under different pumping frequencies, prompting discussion of the impact of velocity anisotropy vs the onset of the instability, and the mechanism of particle diffusion in the velocity space in stable and unstable regimes.

In the frame of the PANDORA_Gr3 project, aiming at measuring for the first time in-plasma nuclear β-decays of astrophysical interest, an innovative multi-diagnostic approach to correlate plasma parameters to nuclear activity has been proposed [1–3]. This is based on several detectors and techniques (optical emission spectroscopy, RF systems, interferopolarimetry) and here we focus on high resolution spatially-resolved X-ray spectroscopy, performed by means of a X-ray pin-hole camera setup sensitive in the 0.5–20 keV energy domain. We present measurements on an Ar plasma heated by Electron Cyclotron Resonance at the ECR-plasma lab of ATOMKI-Debrecen. The achieved spatial and energy resolution were 0.5 mm and 300 eV at 8 keV, respectively [4]. The new algorithm of analysis for single-photon-counted images has been developed allowing an investigation in High-Dynamic-Range (HDR) mode. Hence a spatially resolved quantitative characterization of plasma vs. plasma walls emitted spectra was done; the investigated electrons are the ones crucial for in-plasma ionization. Both stable and turbulent plasma regimes can be investigated.

Iron dysregulation is implicated in numerous diseases, and iron homeostasis is profoundly influenced by the labile iron pool (LIP). Tools to easily observe changes in the LIP are limited, with calcein AM-based assays most widely used. We describe here FlCFe1, a ratiometric analogue of calcein AM, which also provides the capacity for imaging iron in 3D cell models.

In this study, carbon papers and aerogels were prepared from chitosan and graphene layers with aldehydic edge functional groups (G-CHO) able to form chemical bonds with chitosan and thus to form a crosslinked network. A high surface area graphite was edge functionalized with hydroxyl groups (G-OH) through the reaction with KOH. G-CHO, with 4.5 mmol/g of functional group, was prepared from G-OH by means of the Reimer-Tieman reaction. Characterization of the graphitic materials was performed with elemental analysis, titration, X-ray analysis, Raman spectroscopy and by estimating their Hansen solubility parameters. CS and G-CHO were mixed with mortar and pestle and carbon papers and aerogels were obtained from a stable acidic water suspension through casting and liophilization, respectively. Free standing and foldable carbon papers and monolithic aerogels based on a continuous covalent network between G-CHO and CS were prepared. G-CHO, which had about 22 stacked layers, was extensively exfoliated in the carbon paper, as confirmed by the absence of the 002 reflection of the graphitic crystallites in the XRD pattern. Carbon paper was found to be resistant to solvents and to be stable for pH ⩾ 7. Composites revealed electrical conductivity. The covalent network between the graphene layers and CS, suggested by the IR findings, accounts for these results. This work demonstrates the effectiveness of a continuous covalent network between chitosan and graphene layers edge functionalized with tailor made functional groups for the preparation of carbon papers and aerogels and paves the way for the scale up of such a type of composites.

Residence Time Difference fluxgate are low cost magnetic field sensors that shows interesting features in terms of sensitivity and resolution. The RTD readout strategy is known to be simple, low noisy, as well as less computationally intensive compared to traditional frequency domain readouts. For these reasons, the use of RTD-Fluxgate is a strategic choice when weak static or quasi-static magnetic fields have to be measured, especially in harsh environments where the use of more complex solutions is not permitted. This paper focuses on a preliminary analysis aimed to assess the possibility to exploit RTD Fluxgates to non-invasively measure very low ion beam currents, in the range of tens of μΑ, in particle accelerators beamlines. To improve performances of the measurement system a dedicated structure, able to concentrate the magnetic flux in the measurement area, is introduced. Experimental results are presented which demonstrate the possibility to exploit the proposed approach.

Graphene layers were selectively edge-functionalized with oxygenated functional groups, maintaining their bulk structure essentially unaltered. A reaction was performed between polyhydroxylated graphene layers (G–OH) and CHCl3/KOH/H2O. When the reaction with KOH/H2O was performed at 0 °C, by adding successive portions of CHCl3, the functionalization occurred with aldehydic functional groups. When G–OH reacted with CHCl3/KOH at room temperature, benzylic alcohol and carboxy groups were introduced. XPS, IR, Raman, and WAXD analyses indicated that the graphene layers were chemically modified with the abovementioned functional groups, without intercalated and/or absorbed molecules. It can thus be assumed that functionalization of G–OH with aldehydic groups occurred through the Reimer–Tiemann reaction and that the domino Reimer–Tiemann/Cannizzaro reaction led to aldehyde disproportionation. As further evidence and the first viable usage of the functionalization with aldehydic functional groups, chitosan was crosslinked with the graphene layers, obtaining flexible and electrically conductive carbon paper.

At Istituto Nazionale di Fisica Nucleare – Laboratorio Nazionale del Sud (INFN-LNS), a broad experience in the design, construction and commissioning of ECR and microwave ion sources is available. The AISHa ion source has been designed by taking into account the typical requirements of hospital-based facilities, where the minimization of the mean time between failures (MTBF) is a key point together with the maintenance operations, which should be fast and easy. It is intended to be a multipurpose device, operating at 18 GHz, in order to achieve higher plasma densities. It should provide enough versatility for future needs of the hadron therapy, including the ability to run at larger microwave power to produce different species and highly charged ion beams. The source is potentially interesting for any hadron therapy facility using heavy ions. In this paper, we analyzed the dimensional test and electrical test about an innovative solution for the containment chamber that allows us to solve our isolation and structural problems., {"references":["F. Noto et al., Structural Optimization of the AISHa Ion Source – ISBN: 978-0-9910001-8-0 ISSN: 2372-2215","S. Gammino et al., Rev. Sci. Instrum. 70,9 (1999), 3577","S. Gammino, G. Ciavola, Rev. Sci. Instrum. 71, 2 (2000), 631","F. Noto et al. - Structural Mechanics Optimization of the AISHa Ion Source - Proceedings of the International Conference on Computational Methods (Vol.2, 2015) ISSN 2374-3948","L. Celona, et al. - A Compact Multiply Charged Ion Source for Hadron Therapy Facility - Proceedings of IPAC2015, Richmond, VA, USA WEPWA031","F. Noto et al, Optimization of the Gas Flow in a GEM Chamber and Development of the GEM Foil Stretcher. Nuclear Technology & Radiation Protection (2014) ISSN: 1451-3994 - DOI: 10.2298/NTRP140SS39N","Felippa C.A., Introduction to Finite Element Methods, lecture notes, Department of aerospace engineering sciences of the University of Colorado, Boulder, 2004.","COMSOL Multiphysics User's Guide v4.1, COMSOL A B, 2010.","Lewis R.W., Nithiarasu P. & Seetharamu K.N., Fundamentals of the Finite Element Method for Heat and Fluid Flow, New York, John Wiley & Sons, 2004."]}

The design of future high-performing ECRIS will require alternative approaches in microwave-to-plasma coupling, in order to maximize the electron density at relatively low frequency and to reduce the hot electrons formation and their consequences on beam stability and on source reliability. On these purposes, different activities have been carried out at INFN-LNS in the recent past, including advanced modelling, diagnostics, and studies about alternative methods of plasma heating based on electrostatic-waves generation. A description of these activities will be presented, with special emphasis to the microwave to plasma coupling and to the plasma diagnostics. Some of the already collected results have been a basis for the design of the new AISHa source (for hadrontherapy purposes) and for the construction of an innovative prototype named Flexible Plasma Trap: on this machine we will search for newschemes of microwave launching, in synergy with thefull-wave plus kinetic calculations of the wave-to-plasmainteraction mechanism.

This case-control study was aimed at evaluating the distribution of some echocardiographic signs of cardiac organ damages in elderly patients with white coat hypertension (WCH), as compared with a normotensive group of elderly. Correlations between the signs of cardiac organ damages and the clinical and ambulatory blood pressure parameters (obtained by means of a 24-h monitoring) have also been evaluated. The first screening covered 258 elderly subjects of both sexes, aged from 65 to 82 years, with clinical diagnosis of hypertension (systolic and diastolic blood pressures being higher than 160 and 95 mmHg, respectively). Of this group, 116 subjects remained in the final pool, and their echocardiographic parameters were compared with 33 normotensive (N) subjects. Out of the 116 clinically hypertensive patients, 29 (25%) displayed WCH, according to the established criteria. Variance analyses on the ranks followed by Dunn's test revealed no statistically significant differences between the N and WCH groups, while the hypertensive group (H) proved to be significantly different from both the N and the WCH groups. In addition to the descriptive statistics, an analysis of correlations between the pressure variables and the echocardiographic parameters has also been performed by means of a forward-stepwise multiple linear regression method. The models generated by this regression analysis covered only the ambulatory diurnal systolic pressure, and the clinical diastolic pressure in most of the cases of the echocardiographic parameters, taken as independent variables. In all these cases, the standardizecl correlation coefficient of the diurnal systolic pressure was always higher than that of the clinical diastolic pressure, indicating that the echocardiographic parameters depend more strongly on the first than on the second pressure value.

At INFN-LNS innovative techniques of plasma heating are under investigation in order to produce growing intensities of beams of multi-charged ions for particle accelerators. Recently, signatures about electromagnetic-to-electrostatic waves (EMW-ESW) conversion, leading to the formation of an overdense plasmas characterized by high energy content, have been observed. A new X-ray pin-hole camera, allowing two-dimensional resolved spectroscopy and imaging, has been designed and used, showing the formation of hot electron layers when the plasma is heated by ESWs. Electrostatic probes have been used in parallel to measure the plasma bulk density and temperature, and a new microwave interferometer is under design.

This paper has illustrated evolution and trends in automotive electrical distribution systems. The increasing power and complexity requirements for automotive applications such as EDS, combined with ever-shrinking size and weight allowances, is creating a greater need for space/cost optimization while never compromising the design ruggedness. It is extremely important for semiconductor companies, with a clear vision of future needs, to be ready with a suitable product portfolio fulfilling these requirements. STMicroelectronics has well understood this concept: in addition to the newest and very robust HSD generation, named VIPower/spl trade/ M05, it is developing a new family of devices that, with additional functionality and features, will offer a superior, state of the art reference for this kind of applications.

Automotive has become one of the most stringent markets for the semiconductor industry: very "cheap" products manufactured with leading-edge technologies while meeting the highest quality and reliability levels are required. The penetration of semiconductors inside the vehicle is forecasted to rapidly increase in the coming years. According to industry analysts the average silicon content per vehicle will increase from $175 in 1998 to $260 in 2010. Today a high-end vehicle is estimated to contain more than 70 modules with electronics constituting 25% of the vehicle cost and containing $1000 of silicon. Automotive modules, populated with an increasing number of components implementing a wide range of applications, have to deal with higher and higher currents with more and more "intelligence" and diagnostics. The ability to implement smaller, smarter, higher current density devices, without impacting quality and reliability (on the contrary, vastly improving them), results in a significant enhancement for automotive applications. This work will describe several different examples of "state of the art" power ICs from STMicroelectronics. An overview of how technology, design, assembly and test are addressing the specific requirements of the harsh automotive environment will be given.

The so-called white coat effect occurs in about 42% of elderly patients. This phenomenon leads to several problems in treatment and may also cause renal disease. One of the most frequently controlled parameters is microalbuminuria, an index of renal damage. The present case-control study intended to evaluate the urinary excretion of albumin in elderly patients suffering from white coat hypertension, and comparing their data to those of normotensive subjects. In addition, the study searched for correlations between albuminuria and various clinical and ambulatory blood pressure values. A total of 258 patients were enrolled, but after screening, only 129 were considered; 13 of the latter were further excluded because of problems encountered during ambulatory monitoring of arterial blood pressure. Therefore, 116 hypertensive subjects were included in the study. This pool of hypertensive patients was compared to a normotensive group of 33 subjects. The results have shown the occurrence of white coat effect in 25% of cases, and the microalbuminuria of these patients was statistically not significantly different from that of the normotensive group of patients. The microalbuminuria correlated only with ambulatory systolic blood pressure measured during the day.

Activity can significantly change blood pressure. Twenty four hour ambulatory blood pressure monitoring (Holter method) was introduced to optimize diagnosis and the changes in blood pressure. It was flanked by the purpose to use diaries to correlate symptoms and pressure changes, pressure changes and psychophysical activity, life style and drugs. The diary model adopted by us for 380 elderly subjects between 65 and 85 years old is divided into four main sections: 1. general activities (8 items); 2. situational variations (7 items); 3. correlation between symptoms and pressure changes; 4. drug treatment and pressure changes. The aim of our study was to assess the compliance of the elderly to keeping a diary. Our results showed that compliance was satisfactory in 352/380 subjects (93%).

The antihypertensive treatments have resulted in favorable effects in terms of cardiovascular morbidity and mortality in the elderly, but the therapeutic approaches raise problems linked to the pathophysiological aspects of hypertensives and to the reduced homoeostatic capacity of the senile organism. The antihypertensive treatment in elderly must be aimed at achieving a maximal improvement in the cardiovascular risk profile with possibly minimal side effects. The first step is the non-pharmacological therapy which is a hygienic-behavioral program aimed at changing the patient's life style (physical exercise, reduced salt intake, body weight control, etc.). Non-pharmacological therapy in the elderly patients requires a preliminary evaluating protocol and a close monitoring of the individual responses. The diet, restriction of sodium intake (4-6 g/day), and aerobic physical exercise are important for decrease the development and persistence of hypertension. The non-pharmacological therapy has a low antihypertensive action, however, once established, it should not be abandoned, as its association with pharmacological treatment allows the use of fewer and lower doses of drugs, with a consequent reduction of the risks due to side effects.

Summary Casual blood pressure (BP) measurements may sometimes indicate the presence of cardiovascular morbidity and mortality, but the correlations between BP values and the subsequent occurrence of such complications are low. This may depend on the known inability of casual BP measurements to reflect accurately the 24-hour mean and overall profile of the BP. In this study, electrocardiography (ECG) of left ventricular muscle mass was related to various measures of BP during circadian ambulatory BP monitoring in 156 hypertensive and nonhypertensive elderly patients. Multiple regression analysis performed to establish the presence of left ventricular hypertophy (LVH) revealed that the product of ambulatory systolic BP x diastolic BP (p = 0.027) and ambulatory diastolic BP were significant variables. Clinical pressure variables were not significant. Multiple linear regression analysis to establish the degree of LVH in function of the pressure variables generated a model where the variables included are the product of ambulatory systolic BP x diastolic BP (p = 2.7 × 10 −8 ), ambulatory systolic BP (p = 7.8 × 10 −6 ) and ambulatory diastolic BP (p = 2.4 × 10 −6 ). Results obtained agree with the literature and revealed that LVH evaluated using ECGRomhilt-Estes score was correlated in terms of presence/absence of organ damage and in terms of score to ambulatory monitoring values.

Over the last thirty years white coat hypertension has been the object of numerous studies which suggest that the interactions between doctor and patient and environmental, psychological circumstances suffice to determine a significant increase of arterial pressure in subjects who are generally normotense. The aim of this study was to evaluate the prevalence of white coat hypertension in elderly subjects with hypertension which had been diagnosed recently using the traditional sphygmomanometric method three times in the space of one week. We divided 69 patients (age range 60 to 82 years) into three groups depending on their clinic pressures, i.e. patients with isolated systolic, systo-diastolic or diastolic hypertension. Non invasive 24 h pressure ambulatory monitoring was performed in each subject using a Takeda recorder TM 2420 and adopting a protocol for single measurements at 15 minutes intervals between 08.00 and 20.00 (daytime measurements) and 30 minutes intervals between 20.00 and 08.00 (night-time measurements). Ambulatory monitoring with less than 60 recordings, and those where measurements were not taken for over 60 minutes during the day or 90 minutes during the night were excluded from the study, and the mean daytime and 24 h pressure load was calculated. Monitoring conducted in 60 subjects (39 males and 21 females) was considered valid. Statistical analysis of the mean arterial pressure values of each subject determined by the two methods was performed using a t-test.(ABSTRACT TRUNCATED AT 250 WORDS)

The authors reported a case of a child suffering from Cow's milk protein allergy, in which a soybean milk was administered for one month. The incorrect preparation of the formula determined a megaloblastic anaemia due to folate deficiency. The observation of very high levels of seric aminoacids during the acute phase of the disease was noteworthy. The therapy with folic acid and the introduction of protein hydrolysated formula milk determined a rapid normalization of the haematological picture. During the follow-up the administration of soybean protein caused anaphylaxis showing the contemporary presence of soybean allergy. The challenge test with cow's milk performed afterwards showed the restoration of the tolerance towards cow's milk protein.