66 research outputs found
The 72-Hour WEBT Microvariability Observation of Blazar S5 0716+714 in 2009
Context. The international whole earth blazar telescope (WEBT) consortium
planned and carried out three days of intensive micro-variability observations
of S5 0716+714 from February 22, 2009 to February 25, 2009. This object was
chosen due to its bright apparent magnitude range, its high declination, and
its very large duty cycle for micro-variations. Aims. We report here on the
long continuous optical micro-variability light curve of 0716+714 obtained
during the multi-site observing campaign during which the Blazar showed almost
constant variability over a 0.5 magnitude range. The resulting light curve is
presented here for the first time. Observations from participating
observatories were corrected for instrumental differences and combined to
construct the overall smoothed light curve. Methods. Thirty-six observatories
in sixteen countries participated in this continuous monitoring program and
twenty of them submitted data for compilation into a continuous light curve.
The light curve was analyzed using several techniques including Fourier
transform, Wavelet and noise analysis techniques. Those results led us to model
the light curve by attributing the variations to a series of synchrotron
pulses. Results. We have interpreted the observed microvariations in this
extended light curve in terms of a new model consisting of individual
stochastic pulses due to cells in a turbulent jet which are energized by a
passing shock and cool by means of synchrotron emission. We obtained an
excellent fit to the 72-hour light curve with the synchrotron pulse model
Planetary Transits of the Trans-Atlantic Exoplanet Survey- Candidate TrES-1b
The AAVSO compiled 10,560 CCD observations of the suspected exoplanet transit object TrES-1b covering seven complete transit windows, three windows of partial coverage, and coverage of baseline non-transit periods. Visual inspection of the light curves reveals the presence of slight humps at the egress points of some transits. A boot strap Monte Carlo simulation was applied to the data to confirm that the humps exist to a statistically significant degree. However, it does not rule out systemic effects which will be tested with campaigns in the 2005 observing season
Proteins on the catwalk: modelling the structural domains of the CCN family of proteins
The CCN family of proteins (CCN1, CCN2, CCN3, CCN4, CCN5 and CCN6) are multifunctional mosaic proteins that play keys roles in crucial areas of physiology such as angiogenesis, skeletal development tumourigenesis, cell proliferation, adhesion and survival. This expansive repertoire of functions comes through a modular structure of 4 discrete domains that act both independently and in concert. How these interactions with ligands and with neighbouring domains lead to the biological effects is still to be explored but the molecular structure of the domains is likely to play an important role in this. In this review we have highlighted some of the key features of the individual domains of CCN family of proteins based on their biological effects using a homology modelling approach
Economic Freedom as a Driver for Growth in Transition
This paper reviews the political economy view of economic growth in post-communist economies making the transition to free markets, focusing on the role of economic policy and institutions. We test the hypothesis that better institutions, measured in terms of economic freedom, contribute to growth. The empirical results from the cross-section of transition economies confirm this hypothesis. The paper concludes that non-linearities are present in the growth model and that differences arise depending on how economic well-being is defined
Accuracy of automatic analysis of ambulatory recordings of nocturnal breathing disorders is significantly instrumentation dependent
Obstructive sleep apnoea (OSA) is generally diagnosed with ambulatory recordings. Although reliability of automated analysis has been investigated, suitability of one single analysis software for use with different devices is unclear. Here, validity of automatic analysis of recordings with two ambulatory devices and reliability of automatic analysis in detection of mixed and central apnoeas are investigated through 100 and 167 recordings with Venla and Embletta devices, respectively. Recordings were analysed automatically with Somnologica 3.2 and compared to manual analysis. Significant differences were seen between devices in classification of the severity of OSA when automatic analysis was applied. 65.4% and 11.4% of patients with mild obstructive sleep apnoea received false negative diagnosis with Venla and Embletta, respectively. Further, as automatic analysis was seen to have major difficulty in detection and classification of central and mixed apnoeas, manual analysis is suggested when these forms of disease are suspected
Molecular detection of Bartonella spp. in deer ked pupae, adult keds and moose blood in Finland
SUMMARY The deer ked (Lipoptena cervi) is a haematophagous ectoparasite of cervids that harbours haemotrophic Bartonella. A prerequisite for the vector competence of the deer ked is the vertical transmission of the pathogen from the mother to its progeny and transstadial transmission from pupa to winged adult. We screened 1154 pupae and 59 pools of winged adult deer keds from different areas in Finland for Bartonella DNA using PCR. Altogether 13 pupa samples and one winged adult deer ked were positive for the presence of Bartonella DNA. The amplified sequences were closely related to either B. schoenbuchensis or B. bovis. The same lineages were identified in eight blood samples collected from free-ranging moose. This is the first demonstration of Bartonella spp. DNA in a winged adult deer ked and, thus, evidence for potential transstadial transmission of Bartonella spp. in the species
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