6,424 research outputs found
CaSPiS: A Calculus of Sessions, Pipelines and Services
Service-oriented computing is calling for novel computational models and languages with well
disciplined primitives for client-server interaction, structured orchestration and unexpected events handling. We present CaSPiS, a process calculus where the conceptual abstractions of sessioning and pipelining play a central role for modelling service-oriented systems. CaSPiS sessions are two-sided, uniquely named and can be nested. CaSPiS pipelines permit orchestrating the flow of data produced by different sessions. The calculus is also equipped with operators for handling (unexpected) termination of the partner’s side of a session. Several examples are presented to provide evidence of the flexibility of the chosen set of primitives. One key contribution is a fully abstract encoding of Misra et al.’s orchestration language Orc. Another main result shows that in CaSPiS it is possible to program a “graceful termination” of nested sessions, which guarantees that no session is forced to hang forever after the loss of its partner
The admission of accession countries to an enlarged monetary union: a tentative assessment
The enlargement of the European monetary union to include the accession countries (ACs) will not lead to higher average inflation in the enlarged euro area, but only to inflation redistribution across countries if continuity of the monetary policy framework is preserved. In the short term, unanticipated shocks to the real exchange rate may instead affect aggregate inflation if member countries' economic structure differs. When comparing welfare, inflation and output stabilisation, we find that the size, differences in economic structure and the variance-covariance matrix of supply and real exchange rate shocks play a key role. The numerical results indicate that the implications for the euro area are significant only if we assume a strong real exchange rate appreciation and if ACs are weighted in terms of purchasing power parity standards. In the event of real exchange rate or country-specific supply shocks in ACs, the consequences would be limited for both the current and the enlarged euro area, but sizeable for ACs themselves. JEL Classification: E52, E58, F33, F40Accession Countries, Balassa-Samuelson Effect, European Monetary Union, Exchange Rate Regimes, monetary policy
The Eastward Enlargement of the European Monetary Union
The enlargement of the European monetary union to include new EU Member States (NMs) will not lead to higher expected inflation in the enlarged euro area, but only to some redistribution of inflation at the country level, if the policy framework of the monetary authority remains invariant. Shocks to the real exchange rate may affect instead aggregate inflation, if member countries' economic structure differs. The numerical results indicate that the impact on steady state inflation of the current euro area is limited if participating countries are weighted on the basis of nominal GDP and if the upward pressure on the real exchange rate is postulated to be in line with most estimates of the Balassa-Samuelson effect. In the event of real exchange rate or country-specific supply shocks in NMs, the consequences are found to be limited for the current and the enlarged euro area, but sizeable for the NMs themselves.EMU; enlargement; East-Central Europe
Welfare implications of joining a common currency
This paper examines the welfare implications of a country joining a currency union as opposed to operating in a flexible exchange rate regime. At the country level, the suboptimal response to domestic and foreign shocks and the inability of setting inflation at the desired level may be offset by a positive impact on potential output. We show that for entry to be welfare enhancing, the potential output gain must be the larger, the smaller the country, the larger the difference between the standard deviation of supply shocks across the participating countries, the smaller the correlation of countries’ supply shocks and the larger the variance of real exchange rate shocks. JEL Classification: E52, E58, F33, F40Balassa-Samuelson Effect, Currency union, monetary policy, Welfare
Thermal Control of a Dual Mode Parametric Sapphire Transducer
We propose a method to control the thermal stability of a sapphire dielectric
transducer made with two dielectric disks separated by a thin gap and
resonating in the whispering gallery (WG) modes of the electromagnetic field.
The simultaneous measurement of the frequencies of both a WGH mode and a WGE
mode allows one to discriminate the frequency shifts due to gap variations from
those due to temperature instability. A simple model, valid in quasi
equilibrium conditions, describes the frequency shift of the two modes in terms
of four tuning parameters. A procedure for the direct measurement of them is
presented.Comment: 5 pages, 6 figures, presented at EFTF-IFCS joint conference 200
Merger of compact stars in the two-families scenario
We analyse the phenomenological implications of the two-families scenario on
the merger of compact stars. That scenario is based on the coexistence of both
hadronic stars and strange quark stars. After discussing the classification of
the possible mergers, we turn to detailed numerical simulations of the merger
of two hadronic stars, i.e., "first family" stars in which delta resonances and
hyperons are present, and we show results for the threshold mass of such
binaries, for the mass dynamically ejected and the mass of the disk surrounding
the post-merger object. We compare these results with those obtained within the
one-family scenario and we conclude that relevant signatures of the
two-families scenario can be suggested, in particular: the possibility of a
rapid collapse to a black hole for masses even smaller than the ones associated
to GW170817; during the first milliseconds, oscillations of the postmerger
remnant at frequencies higher than the ones obtained in the one-family
scenario; a large value of the mass dynamically ejected and a small mass of the
disk, for binaries of low total mass. Finally, based on a population synthesis
analysis, we present estimates of the number of mergers for: two hadronic
stars; hadronic star - strange quark star; two strange quark stars. We show
that for unequal mass systems and intermediate values of the total mass, the
merger of a hadronic star and a strange quark star is very likely (GW170817 has
a possible interpretation into this category of mergers). On the other hand,
mergers of two strange quark stars are strongly suppressed.Comment: 18 pages, 16 figure
Convective Excitation of Inertial Modes in Binary Neutron Star Mergers
We present the first very long-term simulations (extending up to ~140 ms
after merger) of binary neutron star mergers with piecewise polytropic
equations of state and in full general relativity. Our simulations reveal that
at a time of 30-50 ms after merger, parts of the star become convectively
unstable, which triggers the excitation of inertial modes. The excited inertial
modes are sustained up to several tens of milliseconds and are potentially
observable by the planned third-generation gravitational-wave detectors at
frequencies of a few kilohertz. Since inertial modes depend on the rotation
rate of the star and they are triggered by a convective instability in the
postmerger remnant, their detection in gravitational waves will provide a
unique opportunity to probe the rotational and thermal state of the merger
remnant. In addition, our findings have implications for the long-term
evolution and stability of binary neutron star remnantsComment: 6 pages, 4 figure
Relationship and predictive role of the dual expression of FGFR and IL-8 in metastatic renal cell carcinoma treated with targeted agents
Background/Aim: The expression of IL-8 and FGFR has been related to prognosis and pathological features in renal cell carcinoma. We investigated the relationship between IL-8 and FGFR and the outcome in metastatic renal cell carcinoma (mRCC) patients. Materials and Methods: Clinical data and histological samples of patients affected by mRCC and treated with targeted agents were reviewed. The expression of proteins was assessed using immunohistochemistry. Results: FGFR1, FGFR2, and IL-8 were found to be expressed in 16%, 30%, and 50% of cases, respectively. Significant correlations were found between selected proteins. A lack of expression of FGFR2 and IL8 was found to be correlated with increased progression-free survival (PFS). The survival rate at 24 months was 44%, 38%, and 79% of those expressing both, one, or none of the evaluated proteins, respectively (p=0.047). Conclusion: This analysis found a relationship between the expression of IL-8 and FGFR2 in mRCC patients treated with targeted agents
The impact of an extracurricular outdoor physical activity program on long-term memory in adolescent during COVID-19 pandemic
The present study examined the effects of an 8-week extracurricular outdoor physical activity program aimed to improve long-term memory performance in adolescent concerning the Covid-19 period. Participants were 40 schoolchildren (aged 16-17) who trained twice a week in aerobic exercise two hours per session, randomly assigned to participate in either an extracurricular outdoor physical activity program (EG; n = 20) or a waitlist control group (CG; n = 20). At baseline and after training we administered the Verbal Paired Associates (VPA-I) a subtest of the Wechsler Memory Scale – IV (WMS-IV, 2009), which represents one of the most widely used instruments for assessing explicit episodic memory performance. The results suggested that after 8-week aerobic exercise program students were able to increase their long-term memory, and that this capacity was more evident following physical activity that required greater cognitive involvement
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