In this work, a first cryogenic characterization of a scintillating LiAlO2 single crystal is presented. The results achieved show that this material holds great potential as a target for direct dark ...matter search experiments. Three different detector modules obtained from one crystal grown at the Leibniz-Institut für Kristallzüchtung (IKZ) have been tested to study different properties at cryogenic temperatures. Firstly, two 2.8 g twin crystals were used to build different detector modules which were operated in an above-ground laboratory at the Max Planck Institute for Physics (MPP) in Munich, Germany. The first detector module was used to study the scintillation properties of LiAlO2 at cryogenic temperatures. The second achieved an energy threshold of (213.02±1.48) eV which allows setting a competitive limit on the spin-dependent dark matter particle-proton scattering cross section for dark matter particle masses between 350MeV/c2 and 1.50GeV/c2. Secondly, a detector module with a 373 g LiAlO2 crystal as the main absorber was tested in an underground facility at the Laboratori Nazionali del Gran Sasso (LNGS): from this measurement it was possible to determine the radiopurity of the crystal and study the feasibility of using this material as a neutron flux monitor for low-background experiments.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background: Microvolt T‐wave alternans (MTWA) has been proposed as a predictor of the risk of ventricular tachyarrhythmias (VT) and sudden cardiac death (SCD). Aim of this study was to perform a ...systematic review of the literature and a meta‐analysis of MTWA in primary prevention patients with ischemic and nonischemic cardiomyopathy.
Methods: The positive predictive value (PPV), negative predictive value (NPV), and relative risk (RR) of MTWA in predicting death, cardiac death, and SCD during follow‐up were reported.
Results: Fifteen studies involving 5681 patients (mean age 62 years, mean ejection fraction 32%) were included. The summary PPV during the average 26‐month follow‐up was 14% (95% CI: 13–15); NPV was 95% (95% CI: 94–96), and the univariate RR was 2.35 (95% CI: 1.68–3.28). The predictive value of MTWA was similar in patients with ischemic and nonischemic cardiomyopathy. The average RR for SCD or VT events of an abnormal MTWA was 2.40, similar to that for cardiac death. When we grouped the studies together depending upon whether beta‐blockers were withheld prior to MTWA screening, the beta‐blockers group showed an RR of 5.88. By contrast, the group in which beta‐blocker therapy was withheld had an RR of 1.63.
Conclusion: A positive MTWA determined an approximately 2.5‐fold higher risk of cardiac death and life‐threatening arrhythmia and showed a very high NPV both in ischemic and nonischemic patients. An abnormal MTWA test was associated with a 5‐fold increased risk for cardiac mortality in the low‐indeterminate group and about a 6‐fold increased risk in beta‐blockers group.
Ann Noninvasive Electrocardiol 2011;16(4):388–402
The Cryogenic Underground Observatory for Rare Events (CUORE) is a large-scale cryogenic experiment searching for neutrinoless double-beta decay (0νββ) in 130Te. The CUORE detector is made of natural ...tellurium, providing the possibility of rare event searches on isotopes other than 130Te. In this work we describe a search for neutrinoless positron-emitting electron capture (β+ EC ) decay in 120Te with a total TeO2 exposure of 355.7 kg yr, corresponding to 0.2405 kg yr of 120Te. Albeit 0νββ with two final-state electrons represents the most promising channel, the emission of a positron and two 511-keV γ 's make 0νβ+ EC decay signature extremely clear. To fully exploit the potential offered by the detector modularity we include events with different topology and perform a simultaneous fit of five selected signal signatures. Using blinded data we extract a median exclusion sensitivity of 3.4 × 1022 yr at 90% credibility interval (C.I.). After unblinding we find no evidence of 0νβ+ EC signal and set a 90% C.I. Bayesian lower limit of 2.9 × 1022 yr on 120Te half-life. This result improves by an order of magnitude the existing limit from the combined analysis of CUORE-0 and Cuoricino.
Summary Background Scalp reconstruction after wide tumor excision is particularly challenging. Free tissue transfers, local flaps, or skin grafts can be used but present some disadvantages especially ...with old patients with local advanced cancers, systemic diseases and in patients with a prior history of recurring scalp skin cancers in which the risk of burying a recurring tumor with a flap is likely. The Authors expose their early experience with Integra® dermal regeneration template for scalp reconstruction after scalp tumor excision. Methods Eight patients with primary or secondary scalp tumor underwent a first surgical procedure under local anaesthesia for tumor removal and Integra® positioning followed by a second operation performed three weeks later to reconstruct the defect by removing the superficial silicon layer of Integra® and by covering the defect with a split thickness skin graft. The average surface area of the defect was 143.27 cm2 . The average operating time was 30.4 minutes for the first operation and 45.6 minutes for the second operation. In six cases Integra® was grafted as a classic full-thickness skin graft. In the remaining two cases the Integra® template was meshed. The artificial derma was attached to the edge of the wound by either sutures or staples. Results There was a full graft take on all cases. The mean follow-up was 24 months. In two cases we were able to detect early tumor recurrence two months after the operation. Satisfactory cosmetic and functional results were obtained in all patients. Conclusions In the scalp defect reconstructions after tumor excision, Integra® allows to obtain a thicker and more durable coverage than skin graft on the skull, allowing to detect a tumor recurrence earlier than a flap reconstruction with no risk of burying an eventual underlying residual tumor. These operations are performed under local anaesthesia and are therefore suitable for elderly patients.
The CALICE Semi-Digital Hadronic Calorimeter (SDHCAL) prototype, built in 2011, was exposed to beams of hadrons, electrons and muons in two short periods in 2012 on two different beam lines of the ...CERN SPS. The prototype with its 48 active layers, made of Glass Resistive Plate Chambers and their embedded readout electronics, was run in triggerless and power-pulsing mode. The performance of the SDHCAL during the test beam was found to be very satisfactory with an efficiency exceeding 90% for almost all of the 48 active layers. A linear response (within + or - 5%) and a good energy resolution are obtained for a large range of hadronic energies (5-80 GeV) by applying appropriate calibration coefficients to the collected data for both the Digital (Binary) and the Semi-Digital (Multi-threshold) modes of the SDHCAL prototype. The Semi-Digital mode shows better performance at energies exceeding 30 GeV.
A detailed study of hadronic interactions is presented using data recorded with the highly granular CALICE silicon–tungsten electromagnetic calorimeter. Approximately 350,000 selected π− events at ...energies between 2 and 10GeV have been studied. The predictions of several physics models available within the GEANT4 simulation tool kit are compared to this data. A reasonable overall description of the data is observed; the Monte Carlo predictions are within 20% of the data, and for many observables much closer. The largest quantitative discrepancies are found in the longitudinal and transverse distributions of reconstructed energy.
Background: Aim of our study is to evaluate the economic impact of NASH among diabetic population in Italy and potential benefits of treatments that can slow the disease progression. Methods: A ...Markov model was conducted from the Italian National Healthcare System perspective reporting results at 3, 5, 10 and 15 years. The model included NASH and T2DM patients with all stages of fibrosis (F0-F3), compensated cirrhosis (CC), decompensated cirrhosis (DCC), hepatocellular carcinoma (HCC), liver transplant (LT), post-LT and death. A 1-year model cycle length was considered, with each patient passing through the stages and exiting the model when reached one of mortality states. Transition probabilities and annual cost related to health states were derived from published literature. Moreover, the model made it possible to develop a scenario analysis to simulate the impact of treatments capable of slowing the disease progression in phases F0-F4 (CC). Results: The results highlighted an economic burden of NASH in T2DM patients of approximately 1.4 billion euro, 3.1 billion euro, and 9.4 billion euro, respectively, after 3, 5 and 10 years, reaching about 17.3 billion euro after 15 years. The slowing down of the progression in the early stages of the disease (fibrosis F0-CC) has led to significant savings corresponding to 2.3 billion euro at 15 years. These savings were generated by the reduction of the patients in the advanced stages of the disease, which is linked to a reduction in deaths, equal to 92,208 deaths avoided over a 15-year time horizon. Conclusion: Patients with NASH and T2DM reported an important burden in Italy. It is important to investigate the potential clinical and economic benefits of antidiabetic drugs that have been shown to be effective in preventing the transition to advanced disease, simultaneously acting on the therapeutic goals of diabetic disease. Keywords: non-alcoholic steatohepatitis, type 2 diabetes mellitus, burden of illness, treatment perspectives
The plains of Aurorae and Ophir in the equatorial region of Mars display geomorphic evidence indicative of extensive but generally short-lived paleohydrological processes. Elaver Vallis in Aurorae ...Planum south of Ganges Chasma is an outflow channel system >180 km long, and here inferred to have formed by cataclysmic spillover flooding from a paleolake(s) contained in the Morella crater basin. Ganges Cavus is an enormous 5-km-deep depression of probable collapse origin located in the Morella basin. The fluid responsible for the infilling of the Morella basin likely emerged at least partially through Ganges Cavus or its incipient depression, and it may have been supplied also from small-scale springs in the basin. Similar paleohydrological processes are inferred also in Ophir Planum. It is reasonable to assume that water, sometimes sediment-laden and/or mixed with gases, was the responsible fluid for these phenomena although some of the observed features could be explained by non-aqueous processes such as volcanism. Water emergence may have occurred as consequences of ground ice melting or breaching of cryosphere to release water from the underlying hydrosphere. Dike intrusion is considered to be an important cause of formation for the cavi and smaller depressions in Aurorae and Ophir Plana, explaining also melting of ground ice or breaching of cryosphere. Alternatively, the depressions and crater basins may have been filled by regional groundwater table rising during the period(s) when cryosphere was absent or considerably thin. The large quantities of water necessary for explaining the paleohydrological processes in Aurorae and Ophir Plana could have been derived through crustal migration from the crust of higher plains in western Ophir Planum where water existed in confined aquifers or was produced by melting of ground ice due to magmatic heating or climatic shift, or from a paleolake in Candor Chasma further west.
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