8,091 research outputs found
A unification of RDE model and XCDM model
In this Letter, we propose a new generalized Ricci dark energy (NGR) model to
unify Ricci dark energy (RDE) and XCDM. Our model can distinguish between RDE
and XCDM by introducing a parameter called weight factor. When
, NGR model becomes the usual RDE model. The XCDM model is
corresponding to . Moreover, NGR model permits the situation where
neither nor . We then perform a statefinder analysis on NGR
model to see how effects the trajectory on the plane.
In order to know the value of , we constrain NGR model with latest
observations including type Ia supernovae (SNe Ia) from Union2 set (557 data),
baryonic acoustic oscillation (BAO) observation from the spectroscopic Sloan
Digital Sky Survey (SDSS) data release 7 (DR7) galaxy sample and cosmic
microwave background (CMB) observation from the 7-year Wilkinson Microwave
Anisotropy Probe (WMAP7) results. With Markov Chain Monte Carlo (MCMC) method,
the constraint result is
=, which
manifests the observations prefer a XCDM universe rather than RDE model. It
seems RDE model is ruled out in NGR scenario within regions.
Furthermore, we compare it with some of successful cosmological models using
AIC information criterion. NGR model seems to be a good choice for describing
the universe.Comment: 12 pages, 7 figures, 2 tables. Accepted for publication in PL
Constraints on f(R) cosmologies from strong gravitational lensing systems
f(R) gravity is thought to be an alternative to dark energy which can explain
the acceleration of the universe. It has been tested by different observations
including type Ia supernovae (SNIa), the cosmic microwave background (CMB), the
baryon acoustic oscillations (BAO) and so on. In this Letter, we use the Hubble
constant independent ratio between two angular diameter distances
to constrain f(R) model in Palatini approach . These data are from various large systematic
lensing surveys and lensing by galaxy clusters combined with X-ray
observations. We also combine the lensing data with CMB and BAO, which gives a
stringent constraint. The best-fit results are
or using lensing data only. When combined
with CMB and BAO, the best-fit results are or
. If we further fix (corresponding
to CDM), the best-fit value for is
= for the
lensing analysis and
= for the
combined data, respectively. Our results show that CDM model is within
1 range.Comment: 9 pages, 2 figures, 2 table
Regional health governance: a comparative perspective on EU and ASEAN. EU Centre in Singapore Policy Brief No. 4, June 2012
Globalisation has led to new health challenges for the 21st
Century. These challenges have transnational implications and involve a large range of actors and stakeholders. National governments no longer hold the sole responsibility for the health of their people. These changes in health trends have led to the rise of Global Health Governance as a theoretical notion for health policy-making. The Southeast Asian region is particularly prone to public health threats and it is for this reason that this brief looks at the potential of the Association of Southeast Asian Nations (ASEAN) as a regional organisation to take a lead in health cooperation. Through a comparative study
between the regional mechanisms for health cooperation of the European Union (EU) and ASEAN, we look at how ASEAN could maximise its potential as a global health actor. Regional institutions and a network of civil society
organisations are crucial in relaying global initiatives for
health, and ensuring their effective implementation at the
national level. While the EU benefits from higher degrees of
integration and involvement in the sector of health policy
making, ASEANās role as a regional body for health
governance will depend both on greater horizontal and vertical regional integration through enhanced regional mechanisms and a wider matrix of cooperation
Pay Comparisons: An Analysis of UK University Vice Chancellors Pay Awards
This paper examines UK University Vice Chancellors (VC) pay awards. The empirical analysis, covering the period 1997 to 2002, evaluates the impact upon VC pay awards of university performance measures, an internal pay comparison measure and two external pay comparisons, i.e., the pay of other VCs and the pay of CEOs leading comparable-sized UK firms. We find no evidence that VC pay awards are related to any of the performance measures, though the positive relationship found between changes in the proportion of other highly-paid employees and VC pay awards suggests that internal pay comparisons play an important role in remuneration committee decision making. Of the two external pay benchmarks, the pay received by other VCs has the largest positive impact upon VC pay awards. Nevertheless, the (much smaller) partial adjustment of VC pay explained by the difference between the two external pay benchmarks was also statistically significant. Thus, whilst average VC pay increased by some 40% over the period, this was significantly less than the increase in the pay of comparable UK CEOs. We suggest that this conservatism by university remuneration committees stems largely from political rather than financial constraints
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