9,520 research outputs found
The role of GP’s compensation schemes in diabetes care: evidence from panel data
The design of incentive schemes that improve quality of care is a central issue for the healthcare sector. Nowadays we observe many pay-for-performance programs, where payment is contingent on meeting indicators of provider effort, but also other alternative strategies have been introduced, for example programs rewarding physicians for participation in diseases management plans. Although it has been recognised that incentive-based remuneration schemes can have an impact on GP behaviour, there is still weak empirical evidence on the extent to which such programs influence health outcomes. We investigate the impact of financial incentives in Regional and Local Health Authority contracts for primary care in the Italian Region Emilia Romagna for the years 2003-05. We focus on avoidable hospitalisations (Ambulatory Care Sensitive Conditions) for patients affected by type 2 diabetes mellitus, for which the assumption of responsibility and the adoption of clinical guidelines are specifically rewarded. We estimate a panel count data model using a Negative Binomial distribution to test the hypothesis that, other things equal, patients under the responsibility of GPs receiving a higher share of their income through these programs are less likely to experience avoidable hospitalisations. Our findings support the hypothesis that financial transfers may contribute to improve quality of care, even when they are not based on the ex-post verification of performances.
Affine parameterization of the dark sector: costraints from WMAP5 and SDSS
We study a set of universe models where the dark sector is described by a
perfect fluid with an affine equation of state , focusing
specifically on cosmological perturbations in a flat universe. We perform a
Monte Carlo Markov Chain analysis spanning the full parameter space of the
model using the WMAP 5 years data and the SDSS LRG4 survey. The affine fluid
can either play the role of a unified dark matter (UDM), accounting for both
dark matter and a cosmological constant, or work alongside cold dark matter
(CDM), as a form of dark energy. A key ingredient is the sound speed, that
depends on the nature of the fluid and that, for any given background model,
adds a degree of freedom to the perturbations: in the barotropic case the
square of the sound speed is simply equal to the affine parameter ; if
entropic perturbations are present the effective sound speed has to be
specified as an additional parameter. In addition to the barotropic case, we
consider the two limiting cases of effective sound speed equal to 0 or 1. For
our UDM model is equivalent to the standard CDM with
adiabatic perturbations. Apart of a trivial subcase, all models considered
satisfy the data constraints, with quite standard values for the usual
cosmological parameters. In general our analysis confirms that cosmological
datasets require both a collisionless massive and cold component to form the
potential wells that lead to structure formation, and an effective cosmological
constant that drives the late accelerated expansion.Comment: 10 pages, 9 figure
Chaotic dynamics in a storage-ring Free Electron Laser
The temporal dynamics of a storage-ring Free Electron Laser is here
investigated with particular attention to the case in which an external
modulation is applied to the laser-electron beam detuning. The system is shown
to produce bifurcations, multi-furcations as well as chaotic regimes. The
peculiarities of this phenomenon with respect to the analogous behavior
displayed by conventional laser sources are pointed out. Theoretical results,
obtained by means of a phenomenological model reproducing the evolution of the
main statistical parameters of the system, are shown to be in a good agreement
with experiments carried out on the Super-ACO Free Electron Laser.Comment: submitted to Europ Phys. Journ.
Análise das estratégias de efeito no filme Koyaanisqatsi
In this essay, we try to figure out, based on Wilson Gomes’s filmanalysis methodology and on the musical minimalistic theory, which are the cognitive, sensorial, and emotional elements that are composed in the effect production strategies in the experimental film Koyaanisqatsi (Godfrey Reggio, USA, 1982)
Implementing Session Centered Calculi
Recently, specific attention has been devoted to the development of service oriented process calculi. Besides the foundational aspects, it is also interesting to have prototype implementations for them in order to assess usability and to minimize the gap between theory and practice. Typically, these implementations are done in Java taking advantage of its mechanisms supporting network applications. However, most of the recurrent features of service oriented applications are re-implemented from scratch. In this paper we show how to implement a service oriented calculus, CaSPiS (Calculus of Services with Pipelines and Sessions) using the Java framework IMC, where recurrent mechanisms for network applications are already provided. By using the session oriented and pattern matching communication mechanisms provided by IMC, it is relatively simple to implement in Java all CaSPiS abstractions and thus to easily write the implementation in Java of a CaSPiS process
Chemotherapy accelerates immune-senescence and functional impairments of Vδ2pos T cells in elderly patients affected by liver metastatic colorectal cancer.
Human (gamma delta) γδ T cells are unconventional innate-like lymphocytes displaying a broad array of anti-tumor activities with promising perspectives in cancer immunotherapy. In this context, Vδ2pos T cells represent the preferential target of several immunotherapy protocols against solid tumors. However, the impact of both aging and chemotherapy (CHT) on Vδ2pos T cells is still unknown. The present study evaluates with multi-parametric flow cytometry the frequencies, terminal differentiation, senescence and effector-functions of peripheral blood and tumor infiltrating Vδ2pos T cells purified from liver metastases (CLM) of patients affected by colorectal cancer (CRC) compared to those of sex- and age-matched healthy donors. The peripheral blood of CLM patients underwent CHT is characterized by decreased amounts of Vδ2pos T cells showing a relative increase of terminally-differentiated CD27neg/CD45RApos (TEMRA) cells. The enrichment of this latter subset is associated with an increased expression of the senescent marker CD57. The acquisition of CD57 on TEMRA Vδ2pos T cells is also coupled with impairments in cytotoxicity and production of TNF-α and IFN-γ. These features resemble the acquisition of an immune-senescent profile by Vδ2pos T cells from CLM patients that received CHT, a phenomenon that is also associated with the loss of the co-stimulatory marker CD28 and with the induced expression of CD16. The group of CLM patients underwent CHT and older than 60 years old showed higher frequencies of CD57pos and TEMRA Vδ2pos T cells. Similar results were found for tumor infiltrating Vδ2pos T cell subset purified from CLM specimens of patients treated with CHT. The toxicity of CHT regimens also affects the homeostasis of Vδ2pos T cells by inducing higher frequencies of circulating CD57pos TEMRA subset in CLM underwent CHT and younger than 60 years old. Taken together, our data demonstrate that the enrichment of senescent Vδ2pos T cells in CLM patients is not only induced by patients' aging but also by the toxicity of CHT that further accelerates the accumulation of CD57pos TEMRA cells highly dysfunctional in their anti-tumor activities. These results are important to both predict the clinical outcome of CLM and to optimize those protocols of cell cancer immunotherapy employing unconventional Vδ2pos T cells
Transverse frames for Petrov type I spacetimes: a general algebraic procedure
We develop an algebraic procedure to rotate a general Newman-Penrose tetrad
in a Petrov type I spacetime into a frame with Weyl scalars and
equal to zero, assuming that initially all the Weyl scalars are non
vanishing. The new frame highlights the physical properties of the spacetime.
In particular, in a Petrov Type I spacetime, setting and
to zero makes apparent the superposition of a Coulomb-type effect
with transverse degrees of freedom and .Comment: 10 pages, submitted to Classical Quantum Gravit
Open Transactions on Shared Memory
Transactional memory has arisen as a good way for solving many of the issues
of lock-based programming. However, most implementations admit isolated
transactions only, which are not adequate when we have to coordinate
communicating processes. To this end, in this paper we present OCTM, an
Haskell-like language with open transactions over shared transactional memory:
processes can join transactions at runtime just by accessing to shared
variables. Thus a transaction can co-operate with the environment through
shared variables, but if it is rolled-back, also all its effects on the
environment are retracted. For proving the expressive power of TCCS we give an
implementation of TCCS, a CCS-like calculus with open transactions
Hard - X-rays selected Active Galactic Nuclei. I. A radio view at high-frequencies
A thorough study of radio emission in Active Galactic Nuclei (AGN) is of
fundamental importance to understand the physical mechanisms responsible for
the emission and the interplay between accretion and ejection processes. High
frequency radio observations can target the nuclear contribution of smaller
emitting regions and are less affected by absorption. We present JVLA 22 and 45
GHz observations of 16 nearby (0.003z0.3) hard - X-rays selected AGN
at the (sub)-kpc scale with tens uJy beam sensitivity. We detected 15/16
sources, with flux densities ranging from hundreds uJy beam to tens Jy
(specific luminosities from 10 to 10 at
22 GHz). All detected sources host a compact core, with 8 being core-dominated
at either frequencies, the others exhibiting also extended structures. Spectral
indices range from steep to flat/inverted. We interpret this evidence as either
due to a core+jet system (6/15), a core accompanied by surrounding star
formation (1/15), to a jet oriented close to the line of sight (3/15), to
emission from a corona or the base of a jet (1/15), although there might be
degeneracies between different processes. Four sources require more data to
shed light on their nature. We conclude that, at these frequencies, extended,
optically-thin components are present together with the flat-spectrum core. The
relation is roughly followed, indicating a possible
contribution to radio emission from a hot corona. A weakly significant
correlation between radio core (22 and 45 GHz) and X-rays luminosities is
discussed in the light of an accretion-ejection framework.Comment: Accepted for publication on MNRA
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