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This paper presents microfabric of the Poznań clays in microscopic investigations. The method allows describing the structures after plant roots, Fe-Mn globules, calcareous and siderite concretions, voids after "desert roses" microcrystallites, as well as slickensides. These features are of primary and secondary origin and indicate multistage formation of the studied sediments and polygenenetic processes in their geological history. Root remnants, and slickensides indicate pedogenesis, while microcrystallites, Fe-Mn globules and calcareous concretions were formed during the changes of physical and chemical conditions during weathering processes.

Rostanski K.,University of Silesia | Latowski K.,University Im ckiewicza znaniu
Fragmenta Floristica et Geobotanica Polonica | Year: 2010

In the years 1970-2008 the authors investigated the distribution and taxonomy of the evening-primoses (Oenothera L.) on the territory of the Wielkopolsko-Kujawska Lowland (Wielkopolska region). Totally 24 species and 4 locally appearing hybrids have been found. Similarly as in other Polish regions, in Wielkopolska there are two common species - Oe. biennis and Oe. rubricaulis.

Okonska M.,University Im ckiewicza znaniu | Wolny F.,University Im ckiewicza znaniu
Biuletyn - Panstwowego Instytutu Geologicznego | Year: 2011

In this paper, the results of a hydrogeological reconnaissance are presented. It was performed during the analysis of a tracer migration through an aquifer on a local scale. The research focused on a fragment of the Naramowicki Sandur, a hydrogeological structure located in the vicinity of Poznan, Poland. The subjects of field and laboratory work included describing the geological structure of this area, and measuring the depth of the water table, the directions of water flow and the concentrations of chemical compounds in the groundwater. Some chosen filtration parameters were also analyzed. Furthermore, the relationship between groundwater and surface waters was diagnosed. The analysis of the hydrogeological conditions of the area designated for tracer migration research rendered it possible to properly plan field experiments in a set of observation wells.

Wolny F.,University Im ckiewicza znaniu | Kaczmarek M.,Kazimierz Wielki University in Bydgoszcz | Marciniak M.,University Im ckiewicza znaniu
Biuletyn - Panstwowego Instytutu Geologicznego | Year: 2012

During some PARAMEX field tests an unusual rate-of-rise curve was observed. This curve clearly differed from the exponential curve normally registered during such tests. The atypical curve indicates a faster than usual water level rise during the first stage of the test and a slower rise during the last stage. This type of rise is bi-exponential. Based on the documentation of the analysed piezometers, it should be assumed that this type of water level movement is caused by the dual-permeability of the geological formations surrounding the screened zone. In this paper, the possibility to identify the parameters of such formations using a PARAMEX test is analysed. A model capable of simulating PARAMEX tests in a dual-permeability formation was constructed. Because of the model's shape, the conducted tests were called "W-tube" tests. Water valves at the bottom of the outward columns allowed cutting water flow and therefore registering "U-tube" tests. During these tests, the hydraulic conductivity of a single groundwater formation sample was determined using constant head permeability measurements. A mathematical model of water flow during the laboratory simulation of the PARAMEX test was created. This model allowed interpreting the results laboratory tests: a pair of hydraulic conductivity values was calculated based on the experimentally registered bi-exponential curve. The obtained values of hydraulic conductivity were compared to the values determined during the constant head permeability tests. The mathematical model proved to be adequate for identifying the parameters of dual-permeability based on a PARAMEX test.

Staphylococcal chromosomal cassette mec (SCCmec) is a mobile genetic element that harbors the mec genes which encode resistance to methicillin and almost all β-lactam antibiotics. Also resistance genes for aminoglycosides, macrolides, tetracyclines can accrue on SCCmec elements. Coagulase-negative staphylococci are thought to be a reservoir of diverse SCCmec elements that can spread to Staphylococcus aureus or other species of Staphylococcus. A diversity of SCCmec types, with many new combinations of the mec and ccr gene complex as well as nontypeable types were recognized among the MR-CNS strains.

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