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Among the beam diagnostics routinely employed in source for production of ion of deuterium (SPIDER), beam emission spectroscopy (BES) provides valuable information for beam characterization, thus driving source optimization methods. In particular, this technique is used to measure beam divergence and uniformity, which are crucial parameters to be optimized for application in International Experimental Thermonuclear Reactor (ITER). In this contribution, we focus on the characterization of H-/D- beamlets extracted during the first SPIDER Cs campaigns. In particular, we show parametric scans and preliminary broad component estimates on single beamlets.

Background Glioblastoma (GBM) is the most common primary brain tumor with a poor prognosis, characterized by a high cellular heterogeneity and invasiveness. Multi-drug resistance (MDR), the blood brain barrier (BEE) and DNA repair systems let the survival of tumor cells, making the treatment with chemo and radiotherapy not effective. Autophagy is a physiological mechanism that allows the recycling of damaged proteins and organelles, in order to protect the correct cell turnover. However, in GBM this process promotes survival and proliferation in stressful conditions such as after a chemo and / or radiotherapy treatment. The Hippo pathway is an extremely important molecular signaling because it is involved in various tumorigenesis processes, for instance the epithelium-mesenchymal transition (EMT), in the increase of stemness, mechanotransduction and chemoresistance. Material and Methods The modulation of autophagy was evaluated in GBM cell lines (U87MG, T98G and A172) exploiting a fluorescent detection that allowed the quantification of the autophagosomal activity present into the cell lines. The rate of autophagy was assessed after the cell lines pharmacological treatment with Hippo pathway inhibitors, Verteporfin 2uM (VP) for 24h, Latrunculin 0,5uM (LAT) for 3h and Cytochalasin 1uM (CIT) for 3h, with Doxorubicin 0,5uM (DOX) for 24h and with the drugs combination (DOX-VP, DOX-LAT and DOX-CIT). Moreover, the expression of the autophagy marker LC3II / I was evaluated in all three GBM cell lines by Western Blotting (WB) experiments. To perform this technique, the cells were treated with DOX and Hippo pathway inhibitors respecting the pharmacological treatment previously used. Then, the proteins were extracted, quantified and finally the WB was performed. Results The results obtained showed that the three GBM cell lines without any drugs were marked by high levels of autophagy, similar to the cells treated with Rapamycin, an autophagy inducer. Moreover, the autophagy rate was definitely reduced after treatment with VP and DOX-VP in all three cell lines, including the chemoresistant T98G. Conversely, the other two Hippo pathway inhibitors (LAT-CIT) and DOX did not significantly change the rate of autophagy. The expression of LC3II / I was particularly low after treatment with VP and DOX-VP in all three cell lines while the other two inhibitors did not significantly change its expression. Conclusion In conclusion, these data demonstrated that the three GBM cell lines (U87MG, T98G and A172) are characterized by high levels of autophagy and the inhibition of the Hippo pathway with VP and especially the combination DOX-VP reduced the activation of this protumoral molecular mechanism in GBM cell lines.

The SPIDER experiment, operated at the Neutral Beam Test Facility of Consorzio RFX, Padua, hosts the prototype of the H-/D- ion source for the ITER neutral beam injectors. The maximization of the ion current extracted from the source and the minimization of the amount of co-extracted electrons are among the most relevant targets to accomplish. The Cavity Ring-Down Spectroscopy diagnostic measures the negative ion density in the source close to the acceleration system, so as to have feedback information to optimize the source parameters and to maximize the amount of negative ions that can be extracted at optimal beam divergence. This work shows how the magnetic filter field and the bias currents, present in SPIDER to limit the amount of co-extracted electrons and the electron-ion stripping reactions, affect the density of negative ions available for extraction. Moreover, the influence of the extraction process on the density of negative ions available for extraction is also presented. In this study SPIDER was operated in hydrogen and deuterium in Cs-free conditions, therefore negative ions were mostly produced by reactions in the plasma volume., 13 pages, 8 figures. Preprint of a published paper

BACKGROUND Glioblastoma (GBM) is a primary human malignant brain tumor, the most common in adults. Several studies have highlighted the Hippo-pathway as a cancer signalling network. The Hippo pathway is an evolutionarily conserved signal cascade, which is involved in the control of organ growth. Dysregulations among this pathway have been found in lung, ovarian, liver and colorectal cancer. The key downstream effector of the Hippo-pathway is the Yes-associated protein (YAP); in the nucleus, its function as transcription co-activator is to interact with transcription factors, resulting in the expression of target genes involved in pro-proliferating and anti-apoptotic programs. MATERIAL AND METHODS Using western blotting analysis, we determined the nuclear expression of YAP on three GBM cell lines (U87MG, T98G and A172). To investigate which inhibitors against the Hippo-pathway were the most efficient, we performed a cytotoxic assay: we treated all the three cell lines with different inhibitors such as Verteporfin (VP), Cytochalasin D (CIT), Latrunculin A (LAT), Dobutamine (DOB) and Y27632. Afterwards, we performed a treatment using Doxorubicin (DOX) combined with the inhibitors, evaluating its cytotoxic effect on our cell lines, through cell viability experiments. More western blotting experiments were performed to investigate the oncogenic role of YAP at nucleus level. Furthermore, preliminary experiments have been conducted in order to investigate the apoptosis, senescence and autophagy modulation due to the Hippo-pathway. RESULTS We showed our cell lines express nuclear YAP. We assessed the efficiency of the main inhibitors against Hippo-pathway, proving that VP, LAT A and CIT show a strong cytostatic effect, linked to time increase; plus we saw a cytotoxic effect on T98G. The association of DOX with selected inhibitors is able to reduce cell viability and nuclear YAP expression rate in all three GBM lines. Finally, preliminary experiments were set up to assess how and if the mechanisms of apoptosis, autophagy and senescence were affected by the Hippo-pathway. The combination of DOX with inhibitors promotes resistance to apoptosis. CONCLUSION Our results show that nuclear YAP is present in all tumor lines, thus confirming that this molecular pathway is functioning in GBM lines. Nuclear YAP is more highly expressed after DOX administration. Moreover, the combined treatment (DOX with Hippo-pathway inhibitors) reduces both cell proliferation and viability, and increases the rate of apoptosis. Preliminary experiments on senescence and autophagy were used to determine the best Hippo-pathway inhibitor. These data demonstrate that the Hippo-pathway plays a crucial role in GBM proliferation and resistance to apoptosis. Inhibiting this pathway and in particular the transcription factor YAP, in association with DOX, might be an excellent therapeutic target.

BACKGROUND Meningioma is the most common benign primary intracranial tumor, arising from arachnoid cells of the meninges, but in 20% of cases displays aggressive behavior. Meningiomas are mainly sporadic and the familial forms are very rare. Meningioma account for a small subset (1–4%) of all pediatric brain tumors and may be associated with hereditary tumor predisposition syndrome caused by germline mutations of NF2, SMARCB1, SUFU, and SMARCE1 genes. MATERIAL AND METHODS We present a case of a 16-year-old girl with spinal clear cell meningiomas (CCMs) WHO II with a second spinal lesion identified during the follow-up. Considering the multiple lesions, we performed Whole Exome Sequencing (WES) on DNA from peripheral blood to search for an underlying CCMs tumor predisposition syndrome (#607174). RESULTS We identified a heterozygous frameshift variant c.439delA (p.Ser147fs) in SMARCE1, chromatin remodelling factor that acts as a tumor suppressor gene. Meningioma analysis by Sanger sequencing showed a loss of heterozygosity (LOH) of the wild-type allele. We identified the c.439delA in the constitutional DNA of the father and the sister but not in the mother. At the moment, the father is asymptomatic and the 14 years old sister showed two spinal lesions (meningiomas likely) at the first MRI. CONCLUSION We report a family study of hereditary tumor predisposition syndrome to CCMs with SMARCE1 mutation in which are present two asymptomatic carriers with different ages and gender. The asymptomatic carriers will undergo neurological examination and MRI of the brain and spine, according to a screening protocol. The incomplete penetrance phenomenon is known in SMARCE1-related families with CCMs and it is probably due to the interaction of SMARCE1 with yet unidentified genes.

The combined use of unmanned aerial vehicles (UAV) and radiofrequency identification (RFID) devices is an emerging topic of the environmental monitoring, which combines the versatility of multi-copter airframes with the potentiality of low-cost wireless sensors. This paper introduces some performance metrics suitable to quantify the capability of an RFIDrone to scan a surface equipped with radio-sensors. By using simple propagation models, an optimal drone-surface distance is mathematically derived at the purpose to maximize the electromagnetic footprint for the specific choice of system parameters, such as the sensor type and position, the reader sensitivity, the ground reflectivity, the radiated power, and the flight velocity. Theoretical achievements and some preliminary experimentations indicate that omnidirectional antennas are preferred for the drone so that 9–12 m footprints could be achieved with state-of-the-art readers and battery-less or battery-assisted RFID sensors, provided that the UAV flights at 3–5 m from the surface to be monitored. In this condition, the hit-rate of arrays of tags is better than 90% for a flying speed less than 1.8 km/h. The read performance is instead sensibly degraded by the presence of multi path in case of sensors spaced out the surface.

Self-organization and nonequilibrium phase transitions are well known to occur in two- and three- dimensional dissipative systems. Here, instead, we provide numerical evidence that these phenomena also occur in a one-dimensional Hamiltonian system. To this end, we calculate the heat conductivity by coupling the two ends of our system to two heat baths at different temperatures. It is found that when the temperature difference is smaller than a critical value, the heat conductivity increases with the system size in power law with an exponent considerably smaller than 1. However, as the temperature difference exceeds the critical value, the system's behavior undergoes a transition and the heat conductivity tends to diverge linearly with the system size. Correspondingly, an ordered structure emerges. These findings suggest a new direction for exploring the transport problems in one dimension., 5 pages, 4 figures

We introduce in a unitary way the paradigm of radiofrequency identification (RFID) merged with the technology of Unmanned Aerial Vehicles (UAV) giving rise to RFIDrone devices. Such family comprises the READER-Drone, which is a suitable UAV integrated with an autonomous RFID reader to act as mobile scanner of the environment, and the TAG-Drone, a UAV only equipped with an RFID sensor tag that hence becomes a mobile and automatically re-positioned sensor. We shows some handy electromagnetic models to identify the upper-bound communication performance of RFIDrone in close proximity of a scattering surface and we resume the results of some preliminary open-air experimentation corroborating the theoretical analysis.

Simulating quantum mechanical systems is known to be a difficult computational problem. In particular, for many-body quantum systems the size of the Hilbert space grows exponentially with the number of particles. On the other hand, the growth in memory requirement is only polynomial on a quantum computer, which is itself a many-body quantum system. Therefore, a quantum computer operating with only a few tens of qubits would outperform a classical computer. Moreover, quantum computers with only about ten qubits could efficiently simulate complex single-particle quantum dynamical systems.

We consider classical models of the kicked rotor type, with piecewise linear kicking potentials designed so that momentum changes only by multiples of a given constant. Their dynamics display quasi-localization of momentum, or quadratic growth of energy, depending on the arithmetic nature of the constant. Such purely classical features mimic paradigmatic features of the {\it quantum} kicked rotor, notably dynamical localization in momentum, or quantum resonances. We present a heuristic explanation, based on a classical phase space generalization of a well known argument, that maps the quantum kicked rotor on a tight-binding model with disorder. Such results suggest reconsideration of generally accepted views, that dynamical localization and quantum resonances are a pure result of quantum coherence.

Constraint Induced Movement Therapy (CIMT) in hemiplegic patient is an efficacious method for upper limb rehabilitation.To verify the applicability of CIMT in post stroke inpatients and to verify the predictive value of some clinical and functional independent variables on the outcomes, in order to identify a population of subjects to which this technique can be more effective.Non-controlled clinical study.Seven Italian, non-experimental, Rehabilitation Departments.All post-stroke inpatients (subacute and chronic), consecutively admitted in 7 Rehabilitation Departments, were screened according to our inclusion criteria. The eligible population was assessed according to selected clinical and functional variables at the baseline, and it was evaluated with Wolf Motor Function Test (WMFT-FAS and WMFT-PTT) and Motor Activity Log (MAL-AOU and MAL-QOM), before treatment (T0), after treatment (T1) and at a 3-month follow up (T2). Patients underwent 2 weeks of CIMT from T0.Of the 600 inpatients screened, 44 were admitted in the CIMT protocol and were evaluated at T0 and T1; just 24 completed the assessment at T2. At the end of treatment NIHSS and Motricity Index (MI) were predictive factors of MAL scores, while Geriatric Depression Scale (GDS), Modified Barthel Inedx (MBI) and MI were predictive factors of WMFT scores. At the follow up NIHSS and GDS remained predictive factors of MAL scores, and MBI was predictive of WMFT FAS score.CIMT efficacy did not result to be related to patient's age, mild cognitive deficit, time since stroke. Depression and pinch ability are the main predictors of motor recovery. Despite the demonstrated efficacy, CIMT feasibility still needs to be demonstrated, considering the low percentage (6.5%) of eligibility among all stroke inpatients.CIMT requires high costs and resources; therefore it is valuable to know the predictive factors which help select the eligible patients. It is then useful to recognize the risk factors of developing Learned Non Use after stroke.

MOCVD-TiN deposition from TDMAT precursor consists of two steps: a deposition and a plasma treatment in hydrogen. The effects of different plasma treatment times are tested on high aspect ratio contacts, finding an increase in the number of high resistance contacts for short plasma treatments. Moreover, the W nucleation layer thickness on MOCVD-TiN is impacted by the plasma time: for a short treatment a thin nucleation layer is found. Various investigations are performed on different MOCVD-TiN layers, comparing samples exposed to the air and samples in-situ capped by Ti to prevent oxygen contamination. It is shown that the plasma treatment influences the film morphology.

High vascular morbidity and mortality is associated with acromegaly. The aim of the present study was to assess the effects of octreotide therapy on several known cardiovascular risk factors and to correlate them with octreotide-induced hormonal changes. Lipid levels, LDL particle size distribution as evaluated by single vertical spin density gradient ultracentrifugation, apolipoproteins AI and B, lipoprotein (a) [Lp(a)] concentrations and apo(a) phenotypes were evaluated in 20 non-diabetic acromegalic patients (6 M, 14 F), with normal thyroid, adrenal and gonadal function, aged 29‐66 years. Normal subjects (20), matched for age, sex and BMI served as control for lipid variables. Acromegalic patients were characterized by lower HDL cholesterol (and apoA-I) and by higher Lp(a) concentrations in comparison to controls. Treatment with octreotide (100 mg t.i.d. for 3 months) led to: an increase in HDL cholesterol (median: 22%), a decrease in LDL cholesterol ( 14%) and a decrease of the Lp(a) levels (all phenotypes) (28%). The expected decreases of IGF-I levels (median: 48%) and 7-h AUC of GH ( 50%), insulin (40%), and glucagon (20%) were observed. Only Lp(a) modifications showed a correlation with GH modifications. The study of LDL physical properties showed that acromegalic patients had smaller and:or more dense LDL particles, in comparison with normal controls (relative flotation rate, Rf: 0.4090.03 versus 0.429 0.02 PB 0.05), an alteration that might contribute to the high vascular risk of acromegalic patients. However, the LDL subfraction distribution remained unmodified during octreotide therapy (Rf 0.3990.03). In conclusion, this study shows that in acromegalic patients octreotide treatment is indeed associated with an amelioration of some lipoprotein parameters, i.e. LDL, HDL, and Lp(a) concentrations. However, this treatment has no effect on the small and:or dense LDL particles present in these patients. © 2000 Elsevier Science Ireland Ltd. All rights reserved.

We measured growth hormone (GH), insulin-like growth factor-I (IGF-I), and both total and glycosylated prolactin (PRL) levels in 131 blood samples obtained by cordocentesis in normal and abnormal fetuses from 19 to 40 weeks of gestation. In normal fetuses, IGF-I and PRL levels showed a positive correlation and GH a negative correlation with gestational age. A negative relation between GH and IGF-I levels was observed, while PRL did not show any correlation with both GH and IGF-I concentrations. IGF-I increased from 5.6 +/- 3 (at 19-22 weeks) to 10.7 +/- 5 nmol/l at term; GH decreased from 31 +/- 10 to 7.7 +/- 4 micrograms/l and PRL increased from 16 +/- 18 to 139 +/- 76 micrograms/l. Glycosylated PRL accounted for about 15% of total PRL, a value similar to that found in normal adults. In 27 fetuses of 27-37 weeks with intra-uterine growth retardation, GH and PRL levels were higher and IGF-I levels lower than in normal fetuses matched for week of gestation. In 8 anencephalic fetuses of 19-26 weeks of gestation, both GH and IGF-I levels were lower, and PRL levels were higher than in matched controls. Altogether these data support the views that a) both GH and PRL secretion are under the hypothalamic control during fetal development, b) the serum GH decrease from midgestation to the end of pregnancy is mediated by the negative feed-back mechanism of increasing IGF-I levels and c) IGF-I production is mainly regulated by fuel supply and only partially by GH.

WOS: 000300864200005, The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation gamma-ray spectrometer. AGATA is based on the technique of gamma-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a gamma ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realisation of gamma-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterisation of the crystals was measured and compared with detector-response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximise its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer. (C) 2011 Elsevier B.V. All rights reserved., EU [RII3-CT-2004-506065]; German BMBF [06K-167, 06KY2051]; Swedish Research Council; Knut and Alice Wallenberg Foundation; UK EPSRC Engineering and Physical Sciences Research Council; UK STFC Science and Technology Facilities Council; AWE plc; Scientific and Technological Research Council of Turkey [106T055]; Ankara University [05B4240002]; Polish Ministry of Science and Higher Education [DPN/N190/AGATA/2009]; Spanish MICINN [FPA2008-06419, FPA2009-13377-C02-02]; Spanish Consolider-Ingenio Programme CPAN [CSD2007-00042]; Generalitat Valenciana [PROMETEO/2010/101]; MICINN, Spain; INFN, Italy [AIC10-D-000568]; Science and Technology Facilities Council [ST/F012039/1, ST/J000094/1, ST/F004192/1, ST/J000159/1, ST/I504940/1, NuSTAR, ST/F006950/1, ST/I504916/1, ST/G000670/1, ST/F004060/1, ST/J000051/1, ST/J000108/1, ST/G000670/1 NuSTAR, ST/I504959/1, ST/G000727/1, ST/F004052/1, ST/F004184/1], AGATA and this work is supported by the European funding bodies and the EU Contract RII3-CT-2004-506065, the German BMBF under Grants 06K-167 and 06KY2051, the Swedish Research Council and the Knut and Alice Wallenberg Foundation, UK EPSRC Engineering and Physical Sciences Research Council, UK STFC Science and Technology Facilities Council, AWE plc, Scientific and Technological Research Council of Turkey (Proj. nr. 106T055) and Ankara University (BAP Proj. nr. 05B4240002), the Polish Ministry of Science and Higher Education under Grant DPN/N190/AGATA/2009, the Spanish MICINN under grants FPA2008-06419 and FPA2009-13377-C02-02, the Spanish Consolider-Ingenio 2010 Programme CPAN (contract number CSD2007-00042) the Generalitat Valenciana under Grant PROMETEO/2010/101, and research performed in the frame of the GSI-IN2P3 collaboration agreement number 02-42. A. Gadea and E. Farnea acknowledge the support of MICINN, Spain, and INFN, Italy, through the AIC10-D-000568 bilateral action.

We study the dynamics of a quantum particle in a triangular potential well under a monochromatic driving. We provide a purely quantal theory that accounts for the transition from localization to delocalization, without making reference to the chaotic transition occurring in the classical limit.

We present a quantitative analysis of the reversibility properties of classically chaotic quantum motion by relating the degree of reversibility to the rate at which a quantum state acquires a more and more complicated structure during its time evolution. This complexity can be characterized by the number M(t) of harmonics of the (initially isotropic, i.e. M(0) = 0) Wigner function, which are generated by the time t. We show that, in contrast to the classical exponential increase, this number can grow after the Ehrenfest time tE not faster than linearly. It follows that if the motion is reversed at some arbitrary moment T immediately after applying an instant perturbation with intensity described by the parameter ξ, then there exists a critical perturbation strength, ξc ≈ √ 2/M(T ), below which the initial state is well recovered, whereas reversibility disappears when ξ & ξc(T ). In the classical limit the number of harmonics proliferates exponentially with time and the motion becomes practically irreversible. The above results are illustrated in the example of the kicked quartic oscillator model.

In 2006 SEPA has carried on the installation and tests of a demonstrator for an integrated subway protection system at a new subway station in the Naples (Italy) metropolitan area. Protection of a subway system is a difficult task given the amount of passengers transported every day. The demonstrator has been limited to non-intrusive detection techniques not to impair the passenger flow into the station. The demonstrator integrates several technologies and products that have been developed by SEPA or are already available on the market (MKS Instruments, …). The main purpose is to provide detection capabilities for attempts to introduce radioactive substances in the subway station, in order to foil possible attempts to place a dirty bomb, and threat detection and identification following release of chemical agents. The system integrates additional sensors such as video surveillance cameras and air flow sensing to complement the basic sensors suite. The need to protect sensitive installations such as subway stations has been highlighted by the series of terroristics actions carried out in recent years in the subway in London. However, given the number of passengers of a metro system, it is impossible to propose security techniques operating in ways similar to the screening of passengers in airports. Passengers screening and threat detection and identification must be quick, non-intrusive and capable of screening a large number of passengers to be applicable to mass transit systems. In 2005 SEPA , a small company operating in the field of trains video-surveillance systems and radiation detectors, started developing an integrated system to provide a comprehensive protection to subway stations, based on ready available or off-the-shelf components in order to quickly develop a reliable system with available technology. We ruled out at the beginning any new development in order to speed up the fielding of the system in less than one year. The system was developed with commercial sensors and deployed in a new station of the Naples metropolitan transit system in Mugnano. The station was particularly suitable for the demonstration since it is a new station that includes air venting control, water barriers (for fire and smoke containment) and a complete SCADA system to integrate technical and video surveillance operations. In order to protect the subway, we tackled four basic technologies, all readily available in-house or on the market: • radiation detection, to detect the introduction in the station of radionuclides, that may be dispersed by conventional explosive (a “dirty” bomb); • chemical agents detection and identification (after release), complemented with air speed and velocity sensors to estimate, track and predict the contamination plume; • video surveillance, integrated with the SCADA system and already available in the station.

The localization phenomenon plays an essential role in the excitation of hydrogen atoms in microwave fields. The similarity of this phenomenon to Anderson localization, which has been established and discussed in previous papers, is here demonstrated in a transparent way by reducing the quantum dynamics to a one-dimensional pseudo-Anderson model. The effect of slight changes in the driving frequency on the ionization probability is numerically investigated on the quantum Kepler map; huge fluctuations are found, which persist down to a very fine frequency scale and have a qualitatively random nature. It is argued that such fluctuations are a counterpart of the mesoscopic fluctuations of solid-state physics, and that similar fluctuations should be expected any time, when some classical chaotic diffusive process is quantum-mechanically suppressed by dynamical localization.

This paper is focused on the problem of the spatial localization of radiation-matter interaction in segmented large-volume HPGe detectors. The information is stored in the shapes of the current signals from the various segments. In order to design the algorithms, pulse shapes in a truly coaxial HPGe detector are calculated in closed form. Possible signatures dependent on a single interaction coordinate are found and a rough 3-D localization is obtained. The effects on pulse shapes of the detector encapsulating metallic cluster and of the gaps between sensing electrodes in terms of crosstalks due to capacitive coupling are also investigated.

We focus on the problem of the spatial localization of energy releasing events (hits) in segmented large-volume HPGe detectors. We present an algorithm for a precise radial coordinate estimation of events occurring at the same time in the same segment. The algorithm was designed bearing in mind that, with up to thousands of parallel channels, it is mandatory to perform the measurements in each channel with the least possible number of input data, while losing no important information and, possibly, operating on line in real time. For the sake of simulation, hits with energy ranging from 60 keV up to 2 MeV are taken into account and electronic noise and signal finite bandwidth effects are considered.

We study numerically and analytically the classical one-dimensional Frenkel-Kontorova chain in the regime of pinned phase characterized by phonon gap. Our results show the existence of exponentially many static equilibrium configurations which are exponentially close to the energy of the ground state. The energies of these configurations form a fractal quasi-degenerate band structure which is described on the basis of elementary excitations. Contrary to the ground state, the configurations inside these bands are disordered., Comment: revtex, 9 pages, 9 figures

A novel approach is suggested for the statistical description of quantum systems of interacting particles. The key point of this approach is that a typical eigenstate in the energy representation (shape of eigenstates, SE) has a well defined classical analog which can be easily obtained from the classical equations of motion. Therefore, the occupation numbers for single-particle states can be represented as a convolution of the classical SE with the quantum occupation number operator for non-interacting particles. The latter takes into account the wavefunctions symmetry and depends on the unperturbed energy spectrum only. As a result, the distribution of occupation numbers $n_s$ can be numerically found for a very large number of interacting particles. Using the model of interacting spins we demonstrate that this approach gives a correct description of $n_s$ even in a deep quantum region with few single-particle orbitals., 4 pages, 2 figures

In this paper, we introduce a procedure aimed at measuring the position of charge releasing events within a segmented HPGe γ-ray detector. The proposed method is able to easily discriminate multiple events occurring close in space, even within the same segment. This is crucial in most applications. Limiting factors for the procedure, such as electronic noise and the finite bandwidth of the preamplifier are also considered, their effects modeled and taken into account. The algorithm is not computation intensive and it is meant for real time operation on a simple dedicated hardware.

We study the dynamics of a quantum rotator kicked according to the almost-periodic Fibonacci sequence. A special numerical technique allows us to carry on this investigation for as many as $10^{12}$ kicks. It is shown that above a critical kick strength the excitation of the system is well described by regular diffusion, while below this border it becomes anomalous, and sub-diffusive. A law for the dependence of the exponent of anomalous sub-diffusion on the system parameters is established numerically. The analogy between these results and quantum diffusion in models of quasi-crystal and in the kicked Harper system is discussed., 7 pages, 4 figures, submitted to Phys. Rev. E

The mechanism of action of the synthetic growth hormone (GH)releasing peptide hexarelin is not yet fully understood. Although a direct effect on pituitary cells has been demonstrated, the peptide is also active at hypothalamic level, where specific binding sites have been found. The observation that hexarelin acts synergistically with GH-releasing hormone (GHRH) in releasing GH has suggested that it might suppress endogenous somatostatin secretion. As somatostatin is also inhibitory on TSH secretion, to verify the occurrence of modifications of the somatostatinergic tone induced by hexarelin, we studied its effects on TRH-induced TSH secretion. Seven normal subjects (4 women and 3 men aged 24-29 years) underwent the following tests on 3 different days: a) TRH (200 micrograms/l i.v.) + placebo; b) hexarelin (1 microgram/Kg bw i.v.) + placebo c) combined TRH + hexarelin administration. Hexarelin induced significant and similar increases in serum GH levels when given in combination either with placebo or with TRH (1217 +/- 470 vs 986 +/- 208 micrograms/min/l p:NS), while no modifications of GH levels were seen after TRH + placebo. Serum TSH levels were unmodified by hexarelin + placebo injection. The TSH increase elicited by hexarelin + TRH was superimposable to that elicited by TRH + placebo (1124 +/- 530 and 1273 +/- 380 mU/min/l respectively). Circulating PRL levels slightly increased after hexarelin + placebo too (897 micrograms/min/l), and the PRL response to hexarelin + TRH was slightly, although not significantly, greater than that observed after TRH + placebo (2680 +/- 1517 and 2243 +/- 1108 micrograms/min/l, respectively). In conclusion, our data show that hexarelin does not alter basal and TRH-stimulated TSH secretion, thus suggesting that it does not inhibit somatostatin release. Furthermore a modest PRL-releasing effect of this peptide has been confirmed.

Treatment of acromegaly is effective in reversing the reduced life-span of patients only when serum growth hormone (GH) concentrations are lowered to less than 2.5 micrograms/l. Usual treatments achieve this goal in no more than 50-60% of patients. The effects of octreotide were studied in a prospective, open label study with 68 acromegalic patients enrolled in 10 Italian centers. Octreotide was administered sc at a dose of 100 micrograms t.i.d. for 1 year. After 3 months of therapy, octreotide was effective in decreasing serum GH levels below 2.5 micrograms/l in 16 out of 64 acromegalic patients (25%). Fifteen of them had pretreatment GH levels below 25 micrograms/l. Insulin-like growth factor I (IGF-I) levels normalized in about 40% of patients. No further GH reduction was observed after 1 year of treatment. The presence of abnormal GH responses to thyrotropin-releasing hormone (TRH) and gonadotropin-releasing hormone was reduced from 54 to 24% and from 16 to 12%, respectively. Tumor shrinkage was observed in 50% of 26 non-irradiated patients after 12 months of treatment. Both basal and TRH-stimulated serum prolactin levels significantly decreased in the 11 hyperprolactinemic patients. Although serum thyrotropin, free triiodothyronine and free thyroxine concentrations were not modified, a significant reduction of thyrotropin response to TRH was observed in the 9th month of therapy. In non-diabetic patients, an increase of mean blood glucose levels without modifications of fasting morning concentrations was found. About one-quarter of the patients with overt diabetes mellitus had an impairment of their metabolic control. Main clinical symptoms of acromegaly improved in 70-80% of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum bone Gla protein (BGP), marker of osteoblastic function, carboxyterminal cross-linked telopeptide of type I collagen (ICTP), index of bone resorption, and aminoterminal propeptide of type III procollagen, marker of collagen synthesis, were evaluated in children with GH deficiency (GHD), in adults with childhood-onset GHD and in adults with acquired GHD in adultlife. In children with GHD, serum BGP (12.7 +/- 0.5 ng/ml), ICTP (8.5 +/- 0.9 ng/ml) and PIIINP (3.4 +/- 0.4 ng/ml) were significantly lower (p0.0001, p0.0001 and p0.001, respectively) than those observed in a sex and age matched control group (BGP:18.9 +/- 0.9 ng/ml, ICTP: 14.4 +/- 0.6 ng/ml, PIIINP: 6.7 +/- 0.7 ng/ml). In adults with childhood onsed GHD, BGP levels (3.7 +/- 0.4 ng/ml) were significantly lower (p0.0001) than those recorded in a sex and age matched control group (5.4 +/- 0.1 ng/ml), while ICTP (4.7 +/- 0.7 ng/ml) and PIIINP (3.7 +/- 0.5 ng/ml) levels were similar to those found in controls (ICTP: 4.1 +/- 0.3 ng/ml; PIIINP: 3.3 +/- 0.2 ng/ml). In adults with acquired GHD, serum BGP (5.3 +/- 0.4 ng/ml), ICTP (3.8 +/- 0.4 ng/ml) and PIIINP (3.6 +/- 0.3 ng/ml) levels were not significantly different from those recorded in controls (BGP: 5.4 +/- 0.1 ng/ml, ICTP: 4.1 +/- 0.3 ng/ml, PIIINP: 3.3 +/- 0.2 ng/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Recent studies have revealed the occurrence of rich spectral structures in quantum systems whose classical analogues are two-dimensional area-preserving maps. We show how the spectral measure can be conveniently investigated by means of the thermodynamic formalism.

We present new data from numerical simulations of microwave excitation of a two-dimensional hydrogen atom, which show that in a wide parameter range under the one-dimensional delocalization border, the quantum localization phenomenon persists. We theoretically reconsider the problem of two-dimensional localization, by using an appropriately constructed four-dimensional map over an orbital period of the electron, and thus explain the numerical results.

Eight-four right-handed patients with unilateral hemispheric damage (50 aphasics, 12 non-aphasic left brain-damaged and 22 right brain-damaged patients) and 53 control patients without cerebral lesions were given a test of phoneme identification which examined the S's ability to identify the acoustic boundary between the two phonemes, /d/ and /t/, expressed in terms of voice-onset time (VOT). Phonemic identification defect (PID), defined with reference to the performance of the control group, was found to be virtually limited aphasics; in over 70 per cent of them, the identification of the boundary zone between voiced and voiceless consonants along the VOT continuum was either impossible or abnormal, While neither the fluency - nonfluency dimension of speech nor the level of comprehension seemed to be crucially associated with PID, some evidence pointed to disordered phonemic output as to one dimension of aphasia that is specifically related to it.

We study a free electron laser hamiltonian model for N relativistic electrons interacting with a constant amplitude wiggler field and a laser field. As the amplitude of the wiggler field or the electron density increase above some threshold value, we find a first-order-like transition from an unbunched weakly coupled and ordered motion to a strongly coupled and self-bunched chaotic motion in which the system radiates strongly and cooperatively.

The quantum localization phenomenon that strongly limits any quantum process of diffusive ionization that may be started in systems subjected to a periodic perturbation is discussed. In the case of a highly excited hydrogen atom in a monochromatic field, this phenomenon is theoretically analyzed by reducing the dynamics to appropriate mappings. It is shown that if the field strength is less than a so-called delocalization border, the distribution over unperturbed levels is exponential in the number of absorbed photons and the corresponding localization length is determined. Using the mapping description, it is shown that the excitation process occurring in a two-dimensional atom proceeds essentially along the same lines as in the one-dimensional model. These predictions are supported by results of numerical simulation, and the possibility of their experimental verification is discussed. >