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The aim of this work was to study by a hyphenated HPLC-ICP MS technique the chromium species released during alkaline extraction of various soils collected from a contaminated area of an old tannery. An ultrasound-assisted extraction procedure using 0.1 mol L−1 Na2CO3 solution was developed for the release of chromium species from the soil. The chromium species in the soil extracts were separated on a C8 column using EDTA and TBAH solution as a mobile phase. The use of an ICP-QQQ MS spectrometer in tandem mass configuration (MS/MS) combined with an octopole reaction system (ORS3) pressurized with helium allows one to eliminate spectral interferences during Cr determination in the soil extracts. The detection limit of the procedure was 0.08 µg L−1 for Cr(III) and 0.09 µg L−1 for Cr(VI) species. The trueness of the IP RP HPLC-ICP MS method was proved by an analysis of CRM 041 and CRM 060. The advantage of the proposed method is the analysis of soil extracts without their preliminary neutralization, which limits the losses of Cr(VI) due to the reduction process. The analysed soils mainly contained chromium in immobile forms (94.6–98.5% of the total Cr content). In all alkaline soil extracts mostly the Cr(VI) form was found, but in the extract of organic soils Cr(III) was also present. This arose from the reduction of Cr(VI) species by organic matter (humic acids) and Fe(II). The amount of formed Cr(III) species was dependent on the type of soil (content of organic matter, Mn and Fe) and its moistness. For the first time, the presence of neutral and non-polar chromium fractions in the soil extracts was also demonstrated. It was found that reliable speciation analysis results could be obtained for mineral soils.

W odniesieniu do lokalizacji małych przedsiębiorstw zwykle wskazuje się na duże znaczenie czynników behawioralnych w procesie jej wyboru, w mniejszym stopniu zwraca się zaś uwagę na czynniki strukturalne. W warunkach gospodarki globalnej pojawiły się nowe zjawiska determinujące rozmieszczenie sektora małych przedsiębiorstw. Postęp techniczny zmienia oblicze sektora i jego otoczenia znacznie szybciej, niż to odbywało się w przeszłości. Dlatego celem niniejszego opracowania jest wskazanie roli czynnika strukturalnego w podejmowaniu decyzji lokalizacyjnych w małych firmach na tle cyklu życia przedsiębiorstw oraz nowych trendów zauważanych w praktyce gospodarczej. W artykule zastosowano analizę krytyczną piśmiennictwa, metodę studiów przypadku w oparciu o pogłębione wywiady kwestionariuszowe i wizyty studyjne w parkach naukowo-technologicznych w Gdańsku, Puławach, Rzeszowie, Ełku i Kielcach oraz wyniki badań atrakcyjności inwestycyjnej regionów wykonanych w ramach realizacji badań statutowych w Kolegium Nauk o Przedsiębiorstwie Szkoły Głównej Handlowej w Warszawie. Do nowo zaobserwowanych zjawisk wpływających na lokalizację małych przedsiębiorstw należy zaliczyć: – efekt indukowanej przedsiębiorczości w nowych przestrzeniach produkcyjno-usługowych, tworzonych w miejscach o wyższym standardzie infrastrukturalnym, – pobudzanie przedsiębiorczości w strefach uprzywilejowania ekonomicznego, – outsourcing i offshoring innych przedsiębiorstw w fazie rozwoju, – odnowę strategiczną przedsiębiorstw w fazie schyłkowej, – efekt rozpadu przedsiębiorstw w fazie schyłkowej.

BackgroundComparisons of objectively measured physical activity (PA) between residents of European countries measured concurrently with the same protocol are lacking. We aimed to compare PA between the seven European countries involved in the Food4Me Study, using accelerometer data collected remotely via the Internet.MethodsOf the 1607 participants recruited, 1287 (539 men and 748 women) provided at least 3 weekdays and 2 weekend days of valid accelerometer data (TracmorD) at baseline and were included in the present analyses.ResultsMen were significantly more active than women (physical activity level = 1.74 vs. 1.70, p < 0.001). Time spent in light PA and moderate PA differed significantly between countries but only for women. Adherence to the World Health Organization recommendation to accumulate at least 150 min of moderate-equivalent PA weekly was similar between countries for men (range: 54-65%) but differed significantly between countries for women (range: 26-49%). Prevalence estimates decreased substantially for men and women in all seven countries when PA guidelines were defined as achieving 30 min of moderate and vigorous PA per day.ConclusionsWe were able to obtain valid accelerometer data in real time via the Internet from 80% of participants. Although our estimates are higher compared with data from Sweden, Norway, Portugal and the US, there is room for improvement in PA for all countries involved in the Food4Me Study.

We investigated the growth of straminipilous organisms on the skin, muscles and liver of herbivorous pirapitinga (Piaractus brachypomus) and carnivorous piranha (Pygocentrus nattereri) in water of three different eutrophication levels. Sixteen straminipilous organism species were found growing on the investigated body parts of both species of fish used as baits. The higher number of species was found on the baits of carnivorous species (15) when compared with the ones from the herbivorous pirapitinga (10 species). The highest number of straminipilous organisms species developed on the skin of both species of fish. The highest number of species of straminipilous organisms was observed growing in the water of the BiaBa river (middle eutrophication), while the lowest number occurred in the baits of vessels with water from the Dojlidy pond (low eutrophication).Investigamos o crescimento de organismos stramenophila sobre a pele, músculos e fígado da herbívora pirapitinga (Piaractus brachypomus) e da carnívora piranha (Pygocentrus nattereri) em águas de três diferentes níveis de eutrofização. Dezesseis espécies de organismos stramenophila foram encontradas crescendo sobre as partes do corpo investigadas de ambas as espécies de peixes utilizadas como cobaias. O maior número de espécies foi encontrado em cobaias de espécies carnívoras (15), quando comparado com o da herbívora pirapitinga (10 espécies). A maioria das espécies de organismos stramenophila desenvolveu-se sobre a pele de ambas as espécies de peixes. O maior número de espécies de organismos stramenophila foi observado em crescimento nas águas do rio BiaBa (eutrofização do meio), enquanto o número mais baixo ocorreu em cobaias de vasos com água do lago de Dojlidy (eutrofização baixa).

Objectives: Polypropylene meshes are widely used for surgical treatment of stress urinary incontinence(SUI) and pelvic organ prolapse (POP). Synthesis and deposition of collagen induced by an inserted implant arelargely controlled by oestrogens. The aim of the study was to assess the rate of collagen type I (Col I) synthesisby pubo-cervical fascia (PCF) fibroblasts cultured with mono- or multifilament polypropylene meshes in thepresence of oestrogens. Material and Methods: Specimens of PCF were obtained during a surgical procedure from a 56-year-old womansuffering from SUI and POP. Fibroblasts were cultured with mono- or multifilament meshes and exposed to17β-oestradiol, oestriol or phytoestrogen daidzein. The cultures were run for 216 hrs and the media were replaced every 72 hrs. Procollagen type 1 N-terminal propeptide (PINP), a marker of Col I biosynthesis, was assessedin culture media by radioimmunoassay. Results: The biosynthesis of Col I was more abundant in the presence of monofilament than multifilamentmeshes. Fibroblasts exposed to oestriol or daidzein produced more Col I than those treated with oestradiol,regardless of the mesh applied. In the presence of monofilament mesh the rate of Col I synthesis induced byoestriol and daidzein increased persistently until the end of the experiment, whereas the peak concentration ofPINP in cultures treated with oestradiol was observed between 72 hrs and 144 hrs. In the presence of multifilamentmesh the rate of Col I production dropped after 144 hrs in all cultures. Conclusions: PCF fibroblasts produce more Col I when cultured on monofilament than on multifilamentmesh. This process may be enhanced by oestriol and phytoestrogens.

Nowadays, one of the most important challenge in civil construction is design, build and use buildings in sustainable development way. This article describes one of the most important thermo-modernization undertaking, which is increase of insulation of external walls. The research was prepared in special technology on samples with silicon, mineral, acrylic thin-layer plasters and with adhesive mass only. Purpose of the research was to analyze the physical and mechanical properties of the additional layer with this four variants of plastering mortar. The research, which was made by authors showed that the thin – layer plasters are characterized by resistance to environmental factors, which they are directly exposed. The connection between the individual layers of the thermal insulation system secures durability of the plasters. The samples with mineral plastering mortar were characterized by the highest interlayer adhesion

Process of integration create new challenges with European Union concerning principle function homogeneous market European and growth of competition from part of enterprise. It puts new claims before enterprises in range of preparation of venture, observances and business customs, taking into consideration of possessions of science or suitable creation firm image. However, globalization generates question of new culture of operation, with necessity of utilization of knowledge relate, in information society functioning and appearance new phenomena or instruments. World-wide trends and conversions extract strongest mark on functioning enterprise more. They were object of international scientific conference, that has proceeded in high school of finance and in Warsaw in November 2007.

The article presents the theory of clusters that are treated as natural elements of European model of economic development. There are highlighted Polish Forum of Lisbon Strategy point of view that indicated clusters as one of fundamental ideas recommended for Polish economy. In based on literature and observation of articleís authors the concept, examples of Polish clusters and their role in strategic alliance are presented.

Thyroid peroxidase (TPO) catalyses the biosynthesis of thyroid hormones and is a major autoantigen in Hashimoto's disease--the most common organ-specific autoimmune disease. Epitope mapping studies have shown that the autoimmune response to TPO is directed mainly at two surface regions on the molecule: immunodominant regions A and B (IDR-A, and IDR-B). TPO has been a major target for structural studies for over 20 years; however, to date, the structure of TPO remains to be determined. We have used a molecular modelling approach to investigate plausible modes of TPO structure and dimer organisation. Sequence features of the C-terminus are consistent with a coiled-coil dimerization motif that most likely anchors the TPO dimer in the apical membrane of thyroid follicular cells. Two contrasting models of TPO were produced, differing in the orientation and exposure of their active sites relative to the membrane. Both models are equally plausible based upon the known enzymatic function of TPO. The "trans" model places IDR-B on the membrane-facing side of the myeloperoxidase (MPO)-like domain, potentially hindering access of autoantibodies, necessitating considerable conformational change, and perhaps even dissociation of the dimer into monomers. IDR-A spans MPO- and CCP-like domains and is relatively fragmented compared to IDR-B, therefore most likely requiring domain rearrangements in order to coalesce into one compact epitope. Less epitope fragmentation and higher solvent accessibility of the "cis" model favours it slightly over the "trans" model. Here, IDR-B clusters towards the surface of the MPO-like domain facing the thyroid follicular lumen preventing steric hindrance of autoantibodies. However, conformational rearrangements may still be necessary to allow full engagement with autoantibodies, with IDR-B on both models being close to the dimer interface. Taken together, the modelling highlights the need to consider the oligomeric state of TPO, its conformational properties, and its proximity to the membrane, when interpreting epitope-mapping data.

The present study offers results of analysis concerning the course of reaction between reduced α-lipoic acid (LA) and 2-chloro-1-methylquinolinium tetrafluoroborate (CMQT). In water environments, the reaction between CMQT and hydrophilic thiols proceeds very rapidly and the resultant products are stable. For the described analysis, optimum reaction conditions, such as concentration of the reducing agent, environment pH, and concentration of the reagent were carefully selected. The spectrophotometric assay was carried out measuring absorbance at λ=348 nm (i.e., the spectral band of the obtained reaction product). Furthermore, the calibration curve of lipoic acid was registered. It was concluded that the Lambert-Beer law was observed within the range 1–10 μmol L−1. Later, the reaction between LA and CMQT was used as precolumn derivatization in a chromatographic determination of the lipoic acid in the range 2.5–50 μmol L−1. Practical applicability of the designed methods was evaluated by determining lipoic acid in Revitanerv pharmaceutical preparation which contains 300 mg LA in a single capsule. The error of the determination did not exceed 0.5% in relation to the declared value.

BackgroundBacterial Dsb enzymes are involved in the oxidative folding of many proteins, through the formation of disulfide bonds between their cysteine residues. The Dsb protein network has been well characterized in cells of the model microorganism Escherichia coli. To gain insight into the functioning of the Dsb system in epsilon-Proteobacteria, where it plays an important role in the colonization process, we studied two homologs of the main Escherichia coli Dsb oxidase (EcDsbA) that are present in the cells of the enteric pathogen Campylobacter jejuni, the most frequently reported bacterial cause of human enteritis in the world.Methods and resultsPhylogenetic analysis suggests the horizontal transfer of the epsilon-Proteobacterial DsbAs from a common ancestor to gamma-Proteobacteria, which then gave rise to the DsbL lineage. Phenotype and enzymatic assays suggest that the two C. jejuni DsbAs play different roles in bacterial cells and have divergent substrate spectra. CjDsbA1 is essential for the motility and autoagglutination phenotypes, while CjDsbA2 has no impact on those processes. CjDsbA1 plays a critical role in the oxidative folding that ensures the activity of alkaline phosphatase CjPhoX, whereas CjDsbA2 is crucial for the activity of arylsulfotransferase CjAstA, encoded within the dsbA2-dsbB-astA operon.ConclusionsOur results show that CjDsbA1 is the primary thiol-oxidoreductase affecting life processes associated with bacterial spread and host colonization, as well as ensuring the oxidative folding of particular protein substrates. In contrast, CjDsbA2 activity does not affect the same processes and so far its oxidative folding activity has been demonstrated for one substrate, arylsulfotransferase CjAstA. The results suggest the cooperation between CjDsbA2 and CjDsbB. In the case of the CjDsbA1, this cooperation is not exclusive and there is probably another protein to be identified in C. jejuni cells that acts to re-oxidize CjDsbA1. Altogether the data presented here constitute the considerable insight to the Epsilonproteobacterial Dsb systems, which have been poorly understood so far.

The authors investigated aquatic insects (32 species) as vectors of aquatic zoosporic fungi parasitic on fishes in six bodies of water of various trophic state. A total of 127 zoosporic fungus species were noted, with predominance by the Oomycetes (99) and Chytridiomycetes species (24). Out of these 127 species, 28 are known as parasites or necrotrophs of fishes.

The CuII ion in the title molecular salt, [CuBr(C5H8N2)4]Br, is coordinated in a square-pyramidal geometry by four N atoms of imidazole ligands and one bromide anion in the apical position. In the crystal, the ions are linked by N—H...Br hydrogen bonds involving both the coordinating and the free bromide species as acceptors. A C—H...Br interaction is also observed. Overall, a three-dimensional network results.