2012 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2012

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Modern approach for determination of lactulose, mannitol and sucrose in human urine using HPLC-MS/MS for the studies of intestinal and upper digestive tract permeability
- Paweł Kubica
- Agata Kot-Wasik
- Andrzej Wasik
- Jacek Namieśnik
- Piotr Landowski
2012 Pełny tekst JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES
A new analytical procedure was described for the simultaneous determination of lactulose, mannitol and sucrose in urine, in which HILIC chromatography and tandem mass spectrometry detection are used. Sugars are orally administered for the estimation of intestinal permeability in children digestive tract. Samples were purified by dispersive solid phase extraction (d-SPE) using Amberlite MB150 resin. Raffinose was selected as an internal standard. The chosen chromatographic separation was carried out on ZIC-HILIC column in 10 min at a flow rate of 0.3 mL/min, using mixture of acetonitrile (ACN) and ammonium acetate (NH4Ac) in water (H2O) as the mobile phase. Within-run precision (CV) measured at three concentrations was 1.08%, 0.32% and 0.49% for lactulose; 1.88%, 0.47% and 0.75% for mannitol,2.95%, 1.31% and 0.6% for sucrose. Between-run CVs were 0.75%, 1.1% and 1.2% for lactulose; 1.1%, 1.02% and 1.01% for mannitol; 1.17%, 1.4% and 1.05% for sucrose. Analytical recovery of all three sugar probes was 95.06-99.92%. The detection limits were: 15.94 ng/mL for lactulose, 17.10 ng/mL for sucrose and 11.48 ng/mL for mannitol. The proposed method is rapid, simple, sensitive and suitable for the determination of intestinal permeability of the sugar derivatives in children.
Modern trends in internet marketing - Researching the virality of brands on social media channels
- Bruno Schivinski
- Emilia Nagucka
2012
This paper presents a new approach for the research and identification of users generated content on social media channels. For the online branding research is proposed the use of twi software - SentiOne and NodeXL. The combination of those tools elicit a different point of view of how to manage in an effective way the overflow of the content publish by single individuals in social media networks.
Modern trends in internet marketing - Researching the virality of brands on social media channels
- Bruno Schivinski
- Emilia Nagucka
2012
This paper presents a new approach for the research and identification of users generated content on social media channels. For the online branding research is proposed the use of twi software - SentiOne and NodeXL. The combination of those tools elicit a different point of view of how to manage in an effective way the overflow of the content publish by single individuals in social media networks.
Modernizacje i remonty elektrowni wodnych na rzece Gwda
- Wojciech Szudek
- Witold Sterpejkowicz-Wersocki
2012
Specyficzne warunki środowiskowe budowli hydrotechnicznych powodują ich szybsze starzenie się w porównaniu do innych obiektów budowlanych. Wynika z tego konieczność przeprowadzania systematycznych remontów w celu zapewnienia odpowiedniego stanu technicznego i stopnia bezpieczeństwa budowli piętrzących. W artykule przedstawiono zwięzły opis modernizacji budowli hydrotechnicznych na rz. Gwda przeprowadzonych w ostatnich latach. Pokazano stan budowli przed remontem, występujące uszkodzenia konstrukcji, przyjętą technologię naprawy oraz budowle po przeprowadzeniu remontu.
Modernizacje i remonty elektrowni wodnych na rzece Gwda
- Wojciech Szudek
- Witold Sterpejkowicz-Wersocki
2012
Specificzne warunki środowiskowe budowli hydrotechnicznych powodują ich szybsze starzenie się w porównaniu do innych obiektów budowlanych. W rezultacie jest konieczne przeprowadzenie systematycznych modernizacji i remontów budowli w celu zachowania ich odpowiedniego stanu techniznego oraz stopnia bezpieczeństwa. Przedstawione prace remontowe przeprowadzone w ostatnich latach na stopniach wodnych na rzece Gwda, chociaż dotyczyły głównie napraw konstrukcji betonowych, wskazują na szeroki zakres problemów związanych z utrzymaniem budowli piętrzących. Prace te wymagały podjęcia dużego nakładu sił i środków, a obecnie mogą stanowić przykład przeprowadzenia udanej rewitalizacji starych budowli hydrotechnicznych.
Modernization of the Trailer for Tyre/Road Rolling Resistance Measurements
- Ryszard Woźniak
- Stanisław Taryma
- Grzegorz Ronowski
2012 Key Engineering Materials
In the article the ways of defining tyre rolling resistance are presented. The advantages of the laboratory tests of tyre/road rolling resistance and the advantages and disadvantages of on the road tyre/road rolling resistance tests are described. The description of the special trailer used for tyre/road rolling resistance measurements designed and constructed in the Faculty of Mechanical Engineering at Gdansk University of Technology, is presented also. The trailer is equipped with special test systems which compensate the impact of disturbance factors such as: aerodynamic drag and inertia force acting on the tested tyre, slope of the road, tilt of the trailer and the vibrations of the measuring arm. The article contains the descriptions of the compensation systems applied in the measuring trailer. The conclusions which came from the measurements performed using compensation test systems are included.
Modification of Selected Propagation Models in Terms of Path Loss Estimation in Container Terminal
- Sławomir Ambroziak
- Ryszard Katulski
2012
It is particularly important to look for any propagation model that could be useful for designing mobile radio networks in container terminal environment. Selected propagation models have been investigated. Firstly - basing on measurements results - they have been evaluated in this scope and the analysis has shown, that the adjustment is needed. This modification improved significantly the accuracy of path loss modelling. For the best adjusted model - ITU-R P. 1411 described in §4.2.2 - the mean error equals -0.1 dB, the standard error of estimate equals 5 dB, and the coefficient of determination is 0.785. These results mean that the adjusted model fits very well to experimental data.
Modulacja szerokości impulsu w 9 fazowym silniku indukcyjnym
- Paweł Stec
2012
W referacie przedstawiono sposób modulacji szerokości impulsu falownika dziewięciofazowego. Metoda eliminuje wyższe harmoniczne prądu zasilającego, które mogłyby być generowane w sposób losowy przez falownik, a jednocześnie umożliwia iniekcję pożądanych wyższych harmonicznych do przebiegu prądu silnika. Przedstawiony model umożliwia jego adaptację w falownikowym układzie napędowym i wykorzystanie w wielofazowych układach napędowych co zostało potwierdzone badaniami symulacyjnymi i doświadczalnymi
Modularized Knowledge Bases Using Contexts, Conglomerates and a Query Language
- Krzysztof Goczyła
- Aleksander Waloszek
- Wojciech Waloszek
- Teresa Zawadzka
2012
Artykuł prezentuje nowatorskie podejście do projektowania i budowy baz wiedzy, zorientowane na wyróżnianie kontekstów i ich implementację za pomocą semantycznych modułów wiedzy zwanych konglomeratami.
Modulated crystal structures - periodicity in more than three dimensions
- Andrzej Okuniewski
2012
The initial definition of a crystal was that it is an object with flat faces. When diffraction studies were developed it turned out that crystal consists of a highly ordered particles and it is possible to isolate a small unique part of their structure - a unit cell - and the definition has been changed to rely on this fact. Nowadays by a crystal we mean any solid having an essentially discrete diffraction diagram. It is because in recent years scientists found that there are some solids with discrete diffraction pattern, but there is no possibility to choose any unit cell. This is the case of quasicrystals discovered by Shechtman (Chemistry Nobel Prize 2011), polytypes and incommensurately modulated crystals - these all are called aperiodic crystals. However modulated crystals are not exactly aperiodic - their structures can be described as periodic, but in more than three (up to six) dimensions...
Modulation of carcinogen metabolizing cytochromes p450 in rat liver and kidney by cabbage and sauerkraut juices: comparison with the effects of indole-3-carbinol and phenethyl isothiocyanate
- Hanna Szaefer
- Violetta Krajka-Kuźniak
- Agnieszka Bartoszek-Pączkowska
- Wanda Baer-Dubowska
2012 PHYTOTHERAPY RESEARCH
This study investigated the effect of raw cabbage and sauerkraut juices on the activity and expression of CYP1A1, 1A2, 1B1 and 2B in Wistar rat liver and kidney. The results were compared with those of two commercially available products of glucosinolates degradation: indole-3-carbinol (I3C) and phenethyl isothiocyanate (PEITC). Significant differences in the effect of the cabbage juices as well as I3C and PEITC between the liver and kidney were found. In the liver, both juices decreased the activities of enzymatic markers of CYP1A1 and CYP1A2 after 10 days of the experiment, while in the kidney an enhancement of the activity of these enzymes was observed on days 4 and 10. The increased activity of these enzymes and CYP1A1/1A2 protein level in the liver was found after 30 days of treatment with sauerkraut juice. A similar effect was observed as a result of PEITC treatment. I3C increased the expression and activity of hepatic CYPs at all time points investigated. In conclusion, the present study demonstrates that raw cabbage and sauerkraut juices may affect CYPs involved in the activation of carcinogens/xenobiotics and in this way exert anticarcinogenic activity. The final effects, however, depend on the time-frame of exposure and the type of tissue.
Modulation of CYP19 expression by cabbage juices and their active components: indole-3-carbinol and 3,30-diindolylmethene in human breast epithelial cell lines
- Barbara Licznerska
- Hanna Szaefer
- Mariusz Murias
- Agnieszka Bartoszek-Pączkowska
- Wanda Baer-Dubowska
2012 Pełny tekst EUROPEAN JOURNAL OF NUTRITION
The aim of this study was to evaluate the effect of white cabbage and sauerkraut juices of different origin and indole-3-carbinol (I3C) and diindolylmethane (DIM) on expression of CYP19 gene encoding aromatase, the key enzyme of estrogen synthesis.Remarkable differences in the effect on CYP19 transcript and protein level were found between the cab- bage juices (in 2.5-25 mL/L concentrations) and indoles (in 2.5-50 lM doses) in the three cell lines. While cabbage juices at the lower doses diminished the aromatase expression in nontumorigenic/immortalized MCF10A breast cells (0.25-0.86-fold change), I3C and DIM were more efficient in decreasing the aromatase expression in estrogen-dependant MCF7 breast cancer cells (0.24-0.82-fold change). Inhibition of aromatase by juice obtained from cabbage grown on industrial farm was correlated with the induction of apoptosis (1.7-1.8-fold change) in MCF10A cells. In estrogen- independent MDA-MB-231 cells, up-regulation of CYP19 expression by I3C and DIM (1.5-2.0-fold change) was observed. Similarly, in MCF7 cells juices increased aromatase expression (1.1-2.2-fold change). These results, particularly that obtained in nontumorigenic/immortalized MCF10A cells, suggest that chemopreventive activity of cabbage against breast cancer observed in epidemiological studies may be partly explained by inhibition of the aromatase expression.
Modulation of CYP1A1, CYP1A2 and CYP1B1 expression by cabbage juices and indoles in human breast cell lines
- Hanna Szaefer
- Barbara Licznerska
- Violetta Krajka-Kuźniak
- Agnieszka Bartoszek-Pączkowska
- Wanda Baer-Dubowska
2012 NUTRITION AND CANCER-AN INTERNATIONAL JOURNAL
Epidemiological studies have shown that consumption of cab- bage and sauerkraut is connected with significant reduction of breast cancer incidences. Estrogens are considered a major breast cancer risk factor and their metabolism by P450 enzymes substan- tially contributes to carcinogenic activity. The aim of this study was to investigate the effect of cabbage and sauerkraut juices of differ- ent origin on the expression profile of the estrogen metabolism key enzymes (CYP1A1, CYP1A2, CYP1B1) in breast cell lines MCF7, MDA-MB-231, and MCF10A. The effects of cabbage juices were compared with that exerted by indole-3-carbinol (I3C) and 3,3'- diindolylmethane (DIM). The treatment with cabbage juices or indoles for 72 h affected the expression of CYP1 family genes in cell-type dependent manner. Their induction was found in all cell lines, but the ratio of CYP1A1 to CYP1B1 was 1.22- to 10.6-fold in favor to CYP1A1 in MCF7 and MCF10A cells. Increased lev- els of CYP1A2 in comparison with CYP1B1 were also observed in MCF7 cells. In contrast, in MDA-MB-231 cells CYP1B1 was preferentially induced. Since the cell lines investigated differ in in- vasion capacity, these results support epidemiological observations and partly explain the mechanism of the chemopreventive activity of white cabbage products.
Modyfikacja programu szkolenia kierowców wieloosiowych pojazdów specjalnych, uwzględniająca wyniki badań eksperymentalnych i symulacyjnych eksplozyjnego uszkodzenia opon
- Jerzy Ejsmont
- Grzegorz Motrycz
- Piotr Stryjek
- T Nikisz
- Sylwia Sobieszczyk
2012
Aktualnie obowiązujący program szkolenia kierowców specjalnych pojazdów wojskowych obejmuje zagadnienia związane z budową pojazdu, zasadami jego poprawnej eksploatacji i techniką jazdy w podstawowym zakresie. Program porusza, co prawda również problemy związane z prawidłowym postępowaniem przy wystąpieniu awarii układu napędowego, ale nie obejmuje kompleksowo techniki jazdy w przypadku poważnego uszkodzenia jednego lub więcej kół pojazdu. Nie są również omawianezjawiska zachodzące w chwili najechania na minę, improwizowany ładunek wybuchowy lub spowodowane innymi przyczynami, poważne uszkodzenia koła lub kilku kół. Na podstawie wyników badań eksperymentalnych i symulacyjnych dynamiki pojazdu wieloosiowego w warunkach uszkodzenia ogumienia stwierdzono, że nowy program szkolenia kierowców transporterów opancerzonych powinien zawierać sekwencje jazdy z uszkodzonym ogumieniem przynajmniej na jednej osi kierowanej. Niewątpliwie, dla polepszenia realizmu warto również rozważyć ''treningowy'' najazd na ładunek wybuchowy o mocy równoważnej 0,5 - 0,75 kg TNT. Do tego typu szkolenia należy wykorzystywać koła i opony przeznaczone do złomowania z uwagi na stopień zużycia lub uszkodzenia, co znacznie zmniejszy koszty. W nowym programie szkolenia powinny być także zawarte podstawowe informacje o ładunkach wybuchowych, szczególnie improwizowanych, o rozwiązaniachkonstrukcyjnych zmniejszających skutki wybuchu, o skutkach wybuchu dla wybranych typów pojazdów i o prawidłowym zachowaniu kierowcy po uszkodzeniu jednego lub kilku kół.
Moje spotkania z Szekspirem
- Zbigniew Cywiński
2012 Pismo PG
felieton
Molecular and structural characteristics of cod gelatin films modifiedwith EDC and TGase
- Hanna Staroszczyk
- Julia Pielichowska
- Katarzyna Sztuka
- Janusz Stangret
- Ilona Kołodziejska
2012 Pełny tekst FOOD CHEMISTRY
Cod gelatin films before and after cross-linking of gelatin with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) or transglutaminase (TGase) have been characterized by FT-IR spectroscopy and DSC analysis. For comparison, a film prepared from unmodified pig gelatin has been also analysed. The difference spectra showed that cod gelatin during the film formation involved first of all water-to-amide hydrogen bonds, and the film from pig gelatin contained water-to-amide, amide-to-amide and water-to-water hydrogen bonds. A higher number of hydrogen bonds in the structure of the film from pig gelatin contributed to much better recovering of the helical structure in this film than in the film from cod gelatin. The recovered helical structure, in turn, resulted in a significantly higher melting enthalpy value in the case of the film from the pig gelatin. After modification of cod gelatin with EDC or TGase, the interchain cross-linkages formed in the films led to the conformation of gelatin with no indications of helical ordering. An increase of melting temperature of gelatin films by 7C on EDC and by 10C on the TGase modifications was related to the formation of covalent cross-links, and a decrease of glass temperature by 28C and 7C on EDC and TGase cross-linking, respectively, demonstrated the plasticizing effect of water.
Molecular detection of Candida krusei
- Anna Brillowska-Dąbrowska
- Aleksandra Siniecka
2012 International Research Journal of Microbiology
The species identification of fungi belonging to genus Candida is an important issue as this genus becomes the emerging problem of nosocomial infections. As Candida krusei presents intrinsicresistance to the fluconazole that is the drug of the first choice in case of invasive candidiasis the PCR identifying the DNA of C. krusei was elaborated. The analytical sensitivity of the assay on spiked blood samples was estimated at 3-5 CFU/ml. The possibility of performing the reaction in both end-point and real-time detection format broadened the potential of its application in small and medium microbiology laboratories.
Molecular dynamics and verisimilitude - to what extent can one trust a computational simulation?
- Aleksandra Miszkiel
- Marek Wojciechowski
- Sławomir Milewski
2012
For the last several tens of years, computer simulations have become of undeniable importance. Molecular Dynamics (MD) simulation techniques are used to examine the phenomena which occur at the level that cannot be observed directly. Thus, they can be successfully exploited in many different scientific fields such as: materials science, applied mathematics and theoretical physics, biochemistry, biophysics or drug design. Despite the increasing popularity of this technique, it is still subjected to some kind of restraint and distrust by many of scientists working with traditional methods. The aim of this paper is to show to what extent one can trust a computational simulation made with Molecular Dynamics technique by revealing both major advantages and limitations of this method.
Monitoring of a bathing person
- Adam Bujnowski
- Łukasz Skalski
- Jerzy Wtorek
2012 Journal of Medical Imaging and Health Informatics
W pracy przedstawiono koncepcję i wstępne wyniki układu pozwalającego na monitorowanie stanu i aktywności osoby kąpiącej się. Zaprezentowany system pozwala na wykrycie osoby kąpiącej się w wannie, analizę jej aktywności oraz detekcję stanów potencjalnie niebezpiecznych. W artykule pokazano metodę pomiaru, dokonano analizy czułości, zaprezentowano prototyp układu pomiarowego i wyniki wstępnych pomiarów.
Monitoring of crosslinking of a DGEBA-PAMAM adhesive in composite/aluminium bonded joint using mechanical and ultra-sound techniques
- Michał Budzik
- Benoit Mascaro
- Julien Jumel
- Michel Castaings
- Martin Shanahan
2012 INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
Adhesive cure is an important and determining aspect of strength and stability of bonded structures. Crosslinking of the polymer leads to the adhesive strength, stiffness and durability. Depending on the resin and curing agent used, cure time can vary from minutes to weeks, even then 100% crosslinking not being guaranteed. Standard methods based on dynamic mechanical analysis (DMA) or calorimetric techniques (DSC, DTA) are valuable tools for evaluating short curing times. However, they are devoted specifically to the polymers alone, and not in situ in adhesive joints. In this contribution, we have analysed composite - aluminium joint bonded with a slow-curing DGEBA-PAMAM adhesive system with two new, non-destructive methods. The first is based on measurements obtained from strain gauges mounted on one bonded adherend. The second uses an ultrasound technique based on the through transmission method. Both methods point to the same curing kinetics. Contrary to the classic curing time evolution methods, they are directly applied to adhesive joints where the polymer is only one of the constituents.