KMS conditions for 4-point Green functions at finite temperature

We study the 4-point function in the Keldysh formalism of the closed time path formulation of real time finite temperature field theory. We derive the KMS conditions for these functions and discuss the number of 4-point functions that are independent. We define a set of `physical' functions which are linear combinations of the usual Keldysh functions. We show that these functions satisfy simple KMS conditions. In addition, we consider a set of integral equations which represent a resummation of ladder graphs. We show that these integral equations decouple when one uses the physical functions that we have defined. We discuss the generalization of these results to QED.Comment: 17 pages in Revtex with 2 figure

Children’s residential exposure to selected allergens and microbial indicators: endotoxins and (1→3)-β-D-glucans

Objectives: The study was aimed at assessment of exposure to endotoxins, (1→3)-β-D-glucans and mite, cockroach, cat, dog allergens present in settled dust in premises of children as agents which may be significantly correlated with the occurrence of allergic symptoms and diseases in children. Materials and Methods: The study covered 50 homes of one- or two-year-old children in Poland. Samples of settled dust were taken from the floor and the child's bed. The levels of (1→3)-β-D-glucans (floor), endotoxins (floor) and allergens of mite, cat, dog and cockroach (floor and bed) were analyzed. Results: Average geometric concentrations (geometric standard deviation) of endotoxins, (1→3)-β-D-glucans, Der p1, Fel d1, Can f1 and Bla g1 in children homes were on the floor 42 166.0 EU/g (3.2), 20 478.4 ng/g (2.38), 93.9 ng/g (6.58), 119.8 ng/g (13.0), 288.9 ng/g (3.4), 0.72 U/g (4.4) and in their beds (only allergens) 597.8 ng/g (14.2), 54.1 ng/g (4.4), 158.6 ng/g (3.1) 0.6 U/g (2.9), respectively. When the floor was covered with the carpet, higher concentrations of endotoxins, (1→3)-β-D-glucans and allergens (each type) were found in the settled dust (p < 0.05). The trend was opposite in case of allergens (except dog) analyzed from bed dust and significantly higher concentrations were found in the rooms with smooth floor (p < 0.05). Conclusions: Among the analyzed factors only the type of floor significantly modified both the level of biological indicators and allergens. The results of this study could be the base for verifying a hypothesis that carpeting may have a protective role against high levels of cockroach, dog and cat allergens

Influence of operational parameters on the grinding process of granular material

mieszalniku wstęgowym. W badaniach użyto cząstek węgla aktywnego, a proces mielenia przeprowadzono dla wybranych prędkości obrotów mieszadła: 2; 50 oraz 100 obr min -1. Określono wpływ wybranych parametrów operacyjnych (prędkość obrotowa mieszadła, czas mielenia) na uzyskany skład ziarnowy produktu. Otrzymane wyniki umożliwiły ocenę efektywności prowadzonych prób mielenia.Experimental results dealing with the grinding process of granular material in a ribbon mixer are presented. Activated carbon particles were used in the research. Milling process was performed for the selected stirrer rotational frequencies: 2, 50 and 100 rpm min-1. An influence of selected operational parameters (stirrer rotational frequency, grinding time) on the size distribution of granular material is presented. The results enabled the assessment of grinding test efficiency