Coxiella burnetii as the causative agent of abortions in sheep and goats in Cyprus

One of the most serious problems that we deal with in veterinary services is the issue of abortions in sheep and goats. It is an issue that includes many aspects, among which is the annual cause of negative effects in animal population, in the economy, the loss of animals, the pregnancy time wasted the loss in milk production, etc. Abortions are caused by a number of factors, such as infections by bacteria and viruses, nutritional causes etc. The project is focused on the implementation of molecular methods as a diagnostic tool in cases of abortions in sheep and goats, where C. burnetii could be one of the causative agents The survey took place in Cyprus, and samples from abortions such as placentas and embryos were collected and transferred to the State Official Veterinary laboratories that deal with animal health, for the detection of C. burnetti, using molecular diagnostic methods. At the same time samples were examined in order to exclude other agents that may cause abortions, such as Brucella melitensis, Campylobacter fetus, Chlamydophila psittaci and Anaplasma spp. The results of the research indicated a significant involvement of C. burnetti in abortions in sheep and goats observed in Cyprus. Similar involvement in those abortions seems to have also the pathogen Chlamydophila psittaci. The findings further indicate that the introduction of PCR in the laboratories of the Veterinary Services of Cyprus can be a great diagnostic tool for detection of C. burnetii in abortion materials in combination with the routine method Giemsa stain. Suggestions and recommendations have been made emphasizing the importance of the freshly-implemented technique (PCR) to be adopted in the routine diagnosis and prevention of the pathogen

Variational Data Assimilation via Sparse Regularization

This paper studies the role of sparse regularization in a properly chosen basis for variational data assimilation (VDA) problems. Specifically, it focuses on data assimilation of noisy and down-sampled observations while the state variable of interest exhibits sparsity in the real or transformed domain. We show that in the presence of sparsity, the $\ell_{1}$-norm regularization produces more accurate and stable solutions than the classic data assimilation methods. To motivate further developments of the proposed methodology, assimilation experiments are conducted in the wavelet and spectral domain using the linear advection-diffusion equation

A Study of Halo Coronal Mass Ejections and Related Flare and Radio Burst Observations in Solar Cycle 23

We present a statistical study of dynamical and kinetic characteristics of CMEs which show temporal and spatial association with flares and type II radio bursts or complex radio events of type II bursts and type IV continua. This study is based on a set of earth-directed full halo CMEs occurring during the present solar cycle, with data from the Large Angle Spectrometric Coronagraphs (LASCO) and Extreme-Ultraviolet Imaging Telescope (EIT) aboard the Solar and Heliospheric Observatory (SOHO) mission and the Magnetic Fields Investigation (MFI) and 3-D Plasma and Energetic Particle Analyzer Investigation experiment on board the WIND spacecraft.Comment: Recent Advances in Astronomy and Astrophysics: 7th International Conference of the Hellenic Astronomical Society. AIP Conference Proceedings, Volume 848, pp. 218-223 (2006

Dependence of chaotic diffusion on the size and position of holes

A particle driven by deterministic chaos and moving in a spatially extended environment can exhibit normal diffusion, with its mean square displacement growing proportional to the time. Here we consider the dependence of the diffusion coefficient on the size and the position of areas of phase space linking spatial regions (`holes') in a class of simple one-dimensional, periodically lifted maps. The parameter dependent diffusion coefficient can be obtained analytically via a Taylor-Green-Kubo formula in terms of a functional recursion relation. We find that the diffusion coefficient varies non-monotonically with the size of a hole and its position, which implies that a diffusion coefficient can increase by making the hole smaller. We derive analytic formulas for small holes in terms of periodic orbits covered by the holes. The asymptotic regimes that we observe show deviations from the standard stochastic random walk approximation. The escape rate of the corresponding open system is also calculated. The resulting parameter dependencies are compared with the ones for the diffusion coefficient and explained in terms of periodic orbits.Comment: 12 pages, 5 figure

A Value Flow Model for the Evaluation of an E-Learning Service

Information Systems (IS) evaluation has been one of the most important and widely researched topics for more than two decades. Τhe evaluation of e-Learning is of critical importance in order to maximize the benefits from the huge investments made in this area. In this paper is presented a method for e-learning multi-layer evaluation and value flow model estimation. It includes evaluation of e-learning using three layers of value measures (efficiency measures, effectiveness measures, and intended future behaviour measures), and also the estimation of the relations between them. In this way a model of value generation and flow is developed. This method generates rich and useful information concerning the different types of value that e-learning creates, the mechanisms of their creation and also possible interventions for increasing them. A first application of this method is presented for the evaluation of an e-learning servic

The influence of migrating bed forms on the velocity-intermittency structure of turbulent flow over a gravel bed.

Modeling turbulent flows at high Reynolds number requires solving simplified variants of the Navier-Stokes equations. The methods used to close the resulting Reynolds-averaged, or eddy simulation equations usually follow classical theory and, at small enough scales, postulate universal scaling for turbulence that is independent of the velocity itself. This may not be the best way to conceptualize geophysical turbulence. Turbulent intermittency may be defined in terms of the local “roughness” of the velocity signal as measured by pointwise Hölder exponents. This study investigates the joint velocity-intermittency structure of flow over a gravel-bed surface with migrating bed forms. We report clear velocity-intermittency dependence and quantify its nature above the moving bed form profile. Our results imply differences in energy transfer close to bed forms at shorter wavelengths than those forced directly. Hence, progress in modeling flows of geophysical relevance may require a reconsideration of the principles on which turbulence closures are based

Solvable non-Markovian dynamic network

Non-Markovian processes are widespread in natural and human-made systems, yet explicit modeling and analysis of such systems is underdeveloped. We consider a non-Markovian dynamic network with random link activation and deletion (RLAD) and heavy-tailed Mittag-Leffler distribution for the interevent times. We derive an analytically and computationally tractable system of Kolmogorov-like forward equations utilizing the Caputo derivative for the probability of having a given number of active links in the network and solve them. Simulations for the RLAD are also studied for power-law interevent times and we show excellent agreement with the Mittag-Leffler model. This agreement holds even when the RLAD network dynamics is coupled with the susceptible-infected-susceptible spreading dynamics. Thus, the analytically solvable Mittag-Leffler model provides an excellent approximation to the case when the network dynamics is characterized by power-law-distributed interevent times. We further discuss possible generalizations of our result

The Expression and Functions of Toll-Like Receptors in Atherosclerosis

Inflammation drives atherosclerosis. Both immune and resident vascular cell types are involved in the development of atherosclerotic lesions. The phenotype and function of these cells are key in determining the development of lesions. Toll-like receptors are the most characterised innate immune receptors and are responsible for the recognition of exogenous conserved motifs on pathogens, and, potentially, some endogenous molecules. Both endogenous and exogenous TLR agonists may be present in atherosclerotic plaques. Engagement of toll-like receptors on immune and resident vascular cells can affect atherogenesis as signalling downstream of these receptors can elicit proinflammatory cytokine release, lipid uptake, and foam cell formation and activate cells of the adaptive immune system. In this paper, we will describe the expression of TLRs on immune and resident vascular cells, highlight the TLR ligands that may act through TLRs on these cells, and discuss the consequences of TLR activation in atherosclerosis