1,699 research outputs found
Revenue vs expenditure based fiscal consolidation: the pass-through from federal cuts to local taxes
A growing literature emphasizes that the output effect of fiscal consolidation hinges on its composition, as the choice of increasing revenues vs cutting expenditure is not neutral. Existing studies, however, underscore the role of local governments in a federal setting. Indeed, transfer cuts at the central level might translate into higher local taxes, changing the effective composition of the fiscal adjustment. We evaluate this transmission mechanism in Italy, where municipalities below the threshold of 5,000 inhabitants were exempted from (large) transfer cuts in 2012. This allows us to implement a difference-in-discontinuities design in order to estimate the causal impact of transfer cuts on the composition of fiscal adjustment, also because tight fiscal rules impose a balanced budget on Italian municipalities. We find a pass-through mechanism by which local governments react to the contraction of intergovernmental grants by mainly increasing taxes rather than reducing spending. From a political economy perspective, this revenue based fiscal consolidation is driven by local governments with low electoral competition and low party fragmentation
'SPUTTER-ION PUMPS: PERFORMANCE-ASSESSMENT AND NOBLE-GAS PUMPING OPTIMISATION IN VIEW OF THE COMBINATION WITH NON-EVAPORABLE GETTERS'
The pumping properties of sputter-ion pumps (SIPs) have been studied in view of the combination with non-evaporable getters (NEG) for ultra-high vacuum applications.
Several diode and noble-diode SIPs have been tested on a dedicated test bench and a specific procedure has been tuned, which allows to obtain reliable and reproducible values of pumping speed after saturation for different gases.
In addition, several innovative combinations of cathode materials have been investigated, aiming in particular at an optimised pumping of noble gases and methane. These gas species cannot be pumped by NEG and thus their sorption represents the main task of a SIP in a combination pump.
In parallel, each pair of cathodes has been analysed by FESEM/EDX and XRD, in order to find any possible correlation between their crystal structure, the surface modifications occurred during their functioning and the measured sorption performances
Resonant Axisymmetric Modes
Axisymmetric modes in shaped tokamak plasmas are normally associated with vertical displacement events. However, not enough attention has been given to the fact that these modes can be resonant in two different ways. Firstly, for a plasma bounded by a divertor separatrix, a generic n=0 ideal-MHD perturbation, ξ, is singular at the divertor X- point(s), where Beq · ∇ξ = 0, with Beq the equilibrium magnetic field. As a consequence, n=0 perturbations can give rise to current sheets localized along the divertor separatrix. Secondly, a feedback-stabilized n=0 mode tends to acquire an Alfv ́enic oscillation frequency. As a result, a resonant interaction with energetic particle orbits can lead to a new type of fast ion instability
The predictive role of pelvic magnetic resonance in the follow up of spontaneous or induced puberty in turner syndrome
Puberty is a critical age for patients with Turner syndrome (TS): infertility is reported to be linked to karyotype and spontaneous puberty and menarche occur in approximately 30% of patients, especially in mosaicism. However, it is not always predictable considering hormonal pattern and pelvic transabdominal ultrasound scan (US). The aim of the study is to compare the accuracy of Magnetic Resonance Imaging (MRI) and US to evaluate uterine and gonads volume, to visualize the presence of follicles and to predict spontaneous puberty and menarche in girls with TS. In a retrospective study, we evaluated 19 TS patients (age: 9-16 years), who underwent transabdominal pelvic US and pelvic MRI as required by parents. We correlated pelvic imaging with karyotype, hormonal data and pubertal outcome, and we compared US resolution to MRI. MRI revealed a higher accuracy in the study of uterus and ovaries, and permitted to measure ovaries not visualized by US. Ovarian volume, the presence of follicles and the occurrence of spontaneous puberty were not related to the karyotype; spontaneous puberty started in one patient with a karyotype 45,X and in two patients with mosaicism (45,X/46,XX; 47,XXX/45, X). Ovarian follicles were relieved by MRI in patients with a spontaneous menarche and the persistence of menstrual cycles correlated with an ovarian volume corresponding to Tanner stage 3-4. We stress the role of MRI in the follow-up of TS adolescents, guide in the choice of the timing of treatment
Muon Catalyzed Fusion in 3 K Solid Deuterium
Muon catalyzed fusion in deuterium has traditionally been studied in gaseous
and liquid targets. The TRIUMF solid-hydrogen-layer target system has been used
to study the fusion reaction rates in the solid phase of D_2 at a target
temperature of 3 K. Products of two distinct branches of the reaction were
observed; neutrons by a liquid organic scintillator, and protons by a silicon
detector located inside the target system. The effective molecular formation
rate from the upper hyperfine state of and the hyperfine transition
rate have been measured: , and .
The molecular formation rate is consistent with other recent measurements, but
not with the theory for isolated molecules. The discrepancy may be due to
incomplete thermalization, an effect which was investigated by Monte Carlo
calculations. Information on branching ratio parameters for the s and p wave
d+d nuclear interaction has been extracted.Comment: 19 pages, 11 figures, submitted to PRA Feb 20, 199
Extremely high He isotope ratios in MORB-source mantle from the proto-Iceland plume
The high <sup>3</sup>He/<sup>4</sup>He ratio of volcanic rocks thought to be derived from mantle plumes is taken as evidence for the existence of a mantle reservoir that has remained largely undegassed since the Earth's accretion. The helium isotope composition of this reservoir places constraints on the origin of volatiles within the Earth and on the evolution and structure of the Earth's mantle. Here we show that olivine phenocrysts in picritic basalts presumably derived from the proto-Iceland plume at Baffin Island, Canada, have the highest magmatic <sup>3</sup>He/<sup>4</sup>He ratios yet recorded. A strong correlation between <sup>3</sup>He/<sup>4</sup>He and <sup>87</sup>Sr/<sup>86</sup>Sr, <sup>143</sup>Nd/<sup>144</sup>Nd and trace element ratios demonstrate that the <sup>3</sup>He-rich end-member is present in basalts that are derived from large-volume melts of depleted upper-mantle rocks. This reservoir is consistent with the recharging of depleted upper-mantle rocks by small volumes of primordial volatile-rich lower-mantle material at a thermal boundary layer between convectively isolated reservoirs. The highest <sup>3</sup>He/<sup>4</sup>He basalts from Hawaii and Iceland plot on the observed mixing trend. This indicates that a <sup>3</sup>He-recharged depleted mantle (HRDM) reservoir may be the principal source of high <sup>3</sup>He/<sup>4</sup>He in mantle plumes, and may explain why the helium concentration of the 'plume' component in ocean island basalts is lower than that predicted for a two-layer, steady-state model of mantle structure
Measurement of the Resonant Molecular Formation Rate in Solid HD
Measurements of muon-catalyzed dt fusion () in solid
HD have been performed. The theory describing the energy dependent resonant
molecular formation rate for the reaction + HD is
compared to experimental results in a pure solid HD target. Constraints on the
rates are inferred through the use of a Monte Carlo model developed
specifically for the experiment. From the time-of- flight analysis of fusion
events in 16 and 37 targets, an average formation rate
consistent with 0.897(0.046) (0.166) times the
theoretical prediction was obtained.Comment: 4 pages, 5 figure
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