New quasars behind the Magellanic Clouds. Spectroscopic confirmation of near-infrared selected candidates

Context. Quasi-stellar objects (quasars) located behind nearby galaxies provide an excellent absolute reference system for astrometric studies, but they are difficult to identify because of fore- and background contamination. Deep wide-field, high angular resolution surveys spanning the entire area of nearby galaxies are needed to obtain a complete census of such quasars. Aims. We embarked on a program to expand the quasar reference system behind the Large and the Small Magellanic Clouds, the Magellanic Bridge, and the Magellanic Stream that connects the Clouds with the Milky Way. Methods. Hundreds of quasar candidates were selected based on their near-infrared colors and variability properties from the ongoing public ESO VISTA Magellanic Clouds survey. A subset of 49 objects was followed up with optical spectroscopy. Results. We confirmed the quasar nature of 37 objects (34 new identifications): four are low redshift objects, three are probably stars, and the remaining three lack prominent spectral features for a secure classification. The bona fide quasars, identified from their broad emisison lines, are located as follows: 10 behind the LMC, 13 behind the SMC, and 14 behind the Bridge. The quasars span a redshift range from z ~ 0.5 to z ~ 4.1. Conclusions. Upon completion the VMC survey is expected to yield a total of ~1500 quasars with Y< 19.32 mag, J< 19.09 mag, and Ks< 18.04 mag

From proper motions to star cluster dynamics: measuring velocity dispersion in deconvolved distribution functions

We investigate the effect that the usually large errors associated with ground-based proper motion (PM) components have on the determination of a star cluster's velocity dispersion (\sv). Rather than histograms, we work with PM distribution functions (PMDFs), taking the $1\sigma$ uncertainties formally into account. In this context, a cluster's intrinsic PMDF is broadened by the error distribution function (eDF) that, given the average error amplitude, has a width usually comparable to the cluster PMDF. Thus, we apply a Richardson-Lucy (RL) deconvolution to the PMDFs of a set of relatively nearby and populous open clusters (OCs), using the eDFs as point spread functions (PSFs). The OCs are NGC\,1039 (M\,34), NGC\,2477, NGC\,2516, NGC\,2682 (M\,67), and NGC\,7762. The deconvolved PMDFs are approximately Gaussian in shape, with dispersions lower than the observed ones by a factor of 4-10. NGC\,1039 and NGC\,2516, the nearest OCs of the sample, have deconvolved \sv\ compatible with those of bound OCs of mass $\sim10^3$\,\ms. NGC\,2477 and NGC\,2682 have deconvolved PMDFs with a secondary bump, shifted towards higher average velocities, which may be an artefact of the RL deconvolution when applied to asymmetric profiles. Alternatively, it may originate from cluster merger, large-scale mass segregation or, least probably, binaries.Comment: Accepted by MNRA

Optimizing semiconductor devices by self-organizing particle swarm

A self-organizing particle swarm is presented. It works in dissipative state by employing the small inertia weight, according to experimental analysis on a simplified model, which with fast convergence. Then by recognizing and replacing inactive particles according to the process deviation information of device parameters, the fluctuation is introduced so as to driving the irreversible evolution process with better fitness. The testing on benchmark functions and an application example for device optimization with designed fitness function indicates it improves the performance effectively.Comment: Congress on Evolutionary Computation, 2004. CEC2004. Volume: 2, On page(s): 2017- 2022 Vol.

Handling boundary constraints for numerical optimization by particle swarm flying in periodic search space

The periodic mode is analyzed together with two conventional boundary handling modes for particle swarm. By providing an infinite space that comprises periodic copies of original search space, it avoids possible disorganizing of particle swarm that is induced by the undesired mutations at the boundary. The results on benchmark functions show that particle swarm with periodic mode is capable of improving the search performance significantly, by compared with that of conventional modes and other algorithms.Comment: Congress on Evolutionary Computation, 2004. CEC2004. Volume: 2, On page(s): 2307- 2311 Vol.

Physico-mechanical properties of particleboard made from seaweed adhesive and tapioca starch flo

Flour acted as filler was added into adhesive formulations in industry and it affects the performance of adhesive. Seaweed was chosen to act as adhesive as seaweed produces glue that can attach very strongly to the rocks despite the presence of contaminants. This study was conducted on physical and mechanical properties of particleboard by adding different percentages of tapioca starch flour (0%, 25%, 50%, and 75% based on solid basis) into seaweed adhesive formulation. 100% urea formaldehyde was used as control in the production of particleboard. The particleboards were cut and tested based on JIS A5908. The moisture content was lowered from 11.00 to 8.45% when 25% tapioca starch flour rose to 75% when added into seaweed adhesive. Thickness swelling declined from 40.18 to 26.55% and water absorption from 192.25 to 96.21% when 75% tapioca starch flour was added. Hence, it improved the physical properties of particleboard. Meanwhile, the mixing of higher percentage of tapioca starch flour into seaweed adhesive contributed a higher value of modulus of rupture, modulus of elasticity and internal bonding. In a nutshell, mixing higher percentage of tapioca starch flour in seaweed adhesive improved the physical and mechanical properties of seaweed adhesive in particleboard

Towards a fundamental astrometric reference system behind the Malleganic clouds : spectroscopic confirmation of new quasar candidates selected in the near-infrared

Quasi-stellar objects (quasars) located behind nearby galaxies provide an excellent absolute reference system for astrometric studies, but they are difficult to identify because of fore- and background contamination. We have embarked on a programme to expand the quasar reference system behind the Large and Small Magellanic Clouds, the Magellanic Bridge and Magellanic Stream. Hundreds of quasar candidates were selected, based on their near-infrared colours and variability properties from the ESO VISTA Magellanic Clouds (VMC) Public Survey. A subset of 49 objects was followed up with optical spectroscopy with FORS2. We confirmed the quasar nature of 37 objects (34 new identifications) that span a redshift range from z ~ 0.5 to 4.1

Study on the 4P in the Innovation Strategy of Three Squirrels’ Network Marketing

Along with the rapid development of our electronic commerce in our country, the only traditional marketing mode has been hard to meet the current market demand and it must be imperative to have vast application of marketing innovation strategy. It has been accepted and recognized by more and more people that there is an innovation strategy of network marketing centered with the marketing to improve user brands marketing; what’s more, it has been thought and applied by all kinds of major electronic commerce. Based on the mature theory of innovation strategy of network marketing, the paper would begin from the aspect of improving user brand innovation marketing to have study and analysis of the case of 4P in the innovation strategy of Three Squirrels’ Network Marketing. The successful experience and the currently existed main problem would be analyzed, and some proper suggestions would be mentioned in the paper. The paper would focus on the 4P ideas to analyze the advantages and disadvantages of Three Squirrels to explore the main experience and the existed problems. There would be correspondent improvement innovation strategy combined with the condition of enterprises so that there would be certain reference value for the improvement of Three Squirrels in the network marketing; at the same time, through the ceaseless learning and study, there would be advanced marketing idea and marketing innovation strategy at home and abroad and these could be used by other enterprises in the future so as to have a better promotion to the healthy development of enterprises

Understanding IFNλ in rheumatoid arthritis

Unraveling the mechanisms underlying the inflammatory response in rheumatoid arthritis is crucial in order to better understand the disease and to develop novel therapeutic approaches. Although the effect of type I interferons on fibroblasts and in the context of rheumatoid arthritis has been described for some time, little is known on the effects of the type III interferons, also known as IFNλ. In a previous issue, Xu and colleagues demonstrate that one of the members of the IFNλ family, IFNλ1, enhances Toll-like receptor expression and consequently promotes the production of proinflammatory cytokines known to be involved in initiating and maintaining the inflammatory responses in rheumatoid arthritis