suspended particles with aerodynamic diameters not greater than 2.5 μm (pm2.5) were sampledat the urban background, regional background and urban traffic points in southern poland. in total, 120 sampleswere collected between 2nd august 2009 and 27th december 2010. 16 polycyclic aromatic hydrocarbons (pahs)and organic carbon (oc) were determined in each sample. the samples were collected with a ...

introduction guilan is one of the provinces in north of iran, with population of 2,480,874 and a total area of ​​14,042 square kilometers. this study assesses the outdoor natural gamma dose rates in the air of 49 cities in guilan and calculates corresponding average annual effective dose. materials and methods a total of 260 different sample points measurements were carried out. the results inc...

selective iga deficiency (igad) (serum iga concentration of pcr was used to type hla b, dr, and dq alleles in 29 iranian individuals with igad and 299 swedish individuals with igad. the results indicate a strong association with the hla b14, dr1 alleles in iranian subjects and hla b8, b12, b13, b14, b40, dr1, dr3, dr7, dq2 and dq5 alleles in swedish subjects. differences in hla association of i...

Photoelectron counting distributions are obtained for radiation, consisting of a coherent and a chaotic component, after passage through the turbulent atmosphere. Independent additive background radiation is also taken into account. The counting distributions broaden markedly, and their peak occurs at decreasing count numbers for increasing turbulence. Plots of the distributions are presented f...

There have been great and rapid progresses in the field of γ-ray bursts (denoted as GRBs) since BeppoSAX and other telescopes discovered their afterglows in 1997. Here, we will first give a brief review on the observational facts of GRBs and direct understanding from these facts, which lead to the standard fireball model. The dynamical evolution of the fireball is discussed, especially a generi...

The use of salient regions is an increasingly popular approach to image retrieval. For situations where object retrieval is required and where the foreground and background can be assumed to have different characteristics, it becomes useful to exclude salient regions which are characteristic of the background if they can be identified before matching is undertaken. This paper proposes a techniq...

Properties of the background subtraction procedure commonly used for the analysis of dilepton spectra are discussed within a simple model. It is shown that a production asymmetry between positive and negative background muons and a large multiplicity of signal pairs will lead to biased results. Therefore the applicability of this procedure for the analysis of nucleus–nucleus data should be reco...

The phenotypic effect of mutations can depend on their genetic background, a phenomenon known as epistasis. Many experimental studies have found that epistasis is pervasive, and some indicate that it may follow a general pattern dependent on the fitness effect of the interacting mutations. These studies have, however, typically examined the effect of interactions between a small number of focal...

For action recognition, the actor(s) and the tools they use as well as their motion are of central importance. In this paper, we propose separating foreground items of an action from the background on the basis of motion cues. As a consequence, separate descriptors can be defined for the foreground regions, while combined foreground-background descriptors still capture the context of an action....

In this work we reexamine the opacity of the cosmic background radiation to the propagation of extremely high energy cosmic rays. We use the continuous energy loss approximation to provide spectral modification factors for several hypothesized cosmic ray sources. Earlier problems with this approximation are resolved including the effects of resonances other than the ∆.