University Im ckiewicza znaniu

Poznań, Poland

University Im ckiewicza znaniu

Poznań, Poland
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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.

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.

PubMed | Argonne National Laboratory and University Im ckiewicza znaniu
Type: Journal Article | Journal: Postepy biochemii | Year: 2017

Macromolecules, such as proteins or nucleic acids, form crystals with a large volume fraction of water, ~50% on average. Apart from typical physical defects and rather trivial poor quality problems, macromolecular crystals, as essentially any crystals, can also suffer from several kinds of pathologies, in which everything seems to be perfect, except that from the structural point of view the interpretation may be very difficult, sometimes even impossible. A frequent nuisance is pseudosymmetry, or non-crystallographic symmetry (NCS), which is particularly nasty when it has translational character. Lattice-translocation defects, also called order-disorder twinning (OD-twinning), occur when molecules are packed regularly in layers but the layers are stacked (without rotation) in two (or more) discrete modes, with a unique translocation vector. Crystal twinning arises when twin domains have different orientations, incompatible with the symmetry of the crystal structure. There are also crystals in which the periodic (lattice) order is broken or absent altogether. When the strict short-range translational order from one unit cell to the next is lost but the long-range order is restored by a periodic modulation, we have a modulated crystal structure. In quasicrystals (not observed for macromolecules yet), the periodic order (in 3D space) is lost completely and the diffraction pattern (which is still discrete) cannot be even indexed using three hkl indices. In addition, there are other physical defects and phenomena (such as high mosaicity, diffraction anisotropy, diffuse scattering, etc.) which make diffraction data processing and structure solution difficult or even impossible.

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.

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.

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.

Szolyga M.,University Im ckiewicza znaniu | Dutkiewicz M.,University Im ckiewicza znaniu | Marciniec B.,University Im ckiewicza znaniu | Maciejewski H.,University Im ckiewicza znaniu
Polimery/Polymers | Year: 2013

Aseries of siloxane-silsesquioxane resins with POSS Q8 structures as network nodes containing reactive SiH groups in the siloxane bridges between silsesquioxane (POSS) molecules were prepared in a hydrolytic condensation process. The effect of reactant molar ratios (POSS/ dichloromethylsilane) on the structure of synthesized product was investigated. Attempts were made to carry out the addition reaction of SiH groups with multiple bonds of olefins in the process of hydrosilylation of allyl alcohol. As a result, the resins containing Q8 POSS units and reactive functional groups capable to interact chemically with organic polymers, were obtained. This type of material can be a cheaper but still valuable alternative for the typical POSS compounds.

Lorenc M.,University Im ckiewicza znaniu | Pawlowska K.,University Im ckiewicza znaniu
Przeglad Geologiczny | Year: 2010

4 mammal bone samples were radiocarbon (AMS) dated. The bones come from gravelpit in Krosinko located in WarsawBerlin icemarginal valley, 10 km southwest of Poznań. The ages of the dated bones samples differs considerably. The oldest bone sample comes from the beginning and the youngest one from the end of the Middle Plenivistulian and the difference between them is about 20 000 years.

Szczuka E.,University Im ckiewicza znaniu | Makowska N.,University Im ckiewicza znaniu | Kaznowski A.,University Im ckiewicza znaniu
Postepy Mikrobiologii | Year: 2013

Staphylococci are increasingly recognized as etiological agent of many opportunistic human and animal infections, indicating the need for rapid and accurate identification of these bacteria. In recent years, a significant progress in the identification and phylogenetic studies of Staphylococcus species has been made. In this paper we describe several molecular methods used in taxonomy and identification of staphylococci. The analysis of 16S rRNA gene, gap gene (coding for glyceraldehyde-3-phosphate dehydrogenase), hsp60 gene (encoding heat shock protein Hsp60), dnaJ gene (encoding heat shock protein Hsp40), tuf gene (encoding elongation factor Tu), sodA gene (encoding superoxide dismutase), ropB gene (encoding the beta subunit of RNA polymerase) has been used as tool for the identification of Staphylococcus isolates. Besides the sequence analysis, the PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of core genes (16S rRNA, gap, hsp60, dnaJ, tuf) has been described. Attention is also paid to new molecular methods such as real-time PCR and mass spectrometry.

PubMed | University Im ckiewicza znaniu
Type: Journal Article | Journal: Przeglad lekarski | Year: 2010

The age-specific decline in secretion of androgens and gonadotrophins in men result in negative changes in their libido, and a variety of psychological and neurovegetative symptoms. The purpose of this paper is to describe a diversity of symptoms accompanying males ageing in relation to their biological status, socio-economic background and lifestyle behaviours. The study sample consisted of 2509 men whose age ranged between 30 and 97 years, and who voluntarily completed anonymous questionnaire. The educational attainement, marital status, place of residence, financial situation, physical activity and smoking habit were used to assess demographic and socio-economic status of the studied men. A set of symptoms accompanying males ageing, were classified as somatic (FOSM) and psychological (POSM). Biological status of each man was assessed using index of physiological reserve (WRF) a criterion of biological age. All computations were run using Statistica 7.1 programme package. The level of significance was set at p < or = 0.05. Men who did not experience somatic and psychological symptoms were more likely to be younger (< 50 years) residents of medium cities. Those who had experienced almost all symptoms were more likely to be from the older group (> 50 years) of single men (including bachelors, widowers and divorced). The findings revealed that variation of somatic symptoms accompanying males ageing (FOSM) was in 24% explained (R2 = 0.24) by the set of variables: index of physiological reserve (WRF), calendar age, place of residence, smoking habit and financial situation. Whereas that of POSM, was in 26% explained by index of physiological reserve (WRF), place of residence, marital status and smoking habit. The concluding statement should be stated that somatic and psychological symptoms accompanying males ageing are associated with negative age-related physiological changes in the organism along with negative changes in family and professional lives.

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