2018 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2018

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Anterior subcutaneous transposition and simple decompression of the ulnar nerve at the elbow – the postoperative improvement in DASH score, VAS score and sonographic findings
- B. Igielska
- Boguslaw Baczkowski
- Karol Flisikowski
2018 Pełny tekst Chirurgia Narządów Ruchu i Ortopedia Polska - Polish Orthopaedics
Introduction. Although a lot of studies have described long- term outcomes after surgical treatment of cubital tunnel syndrome, and the usefulness of sonography in diagnosing of this disorder, few studies have evaluated patients self-reporting outcomes or sonographic findings after surgery. Aim. We assessed patients self-reporting instruments and sonographic findings in patients with the cubital tunnel syndrome before and after a surgery. Materials and methods. Forty patients with moderate cubital tunnel syndrome admitted to an orthopedic department were included. Patients underwent an ultrasound examination, filled a DASH questionnaire before, three months and six months after the operation. They had also their symptoms rated with the VAS scale before and six months postoperatively. Patients with clinical signs of subluxation of the nerve during the operation were allocated to a “transposition” group. Patients without these signs had an in situ release. The statistical analyses were made using a nonparametric Friedman ANOVA test for DASH score and Wilcoxon matched-pairs signed-ranks test for VAS scale. Results. After the in situ release, there was a higher difference in the cross-sectional area of the nerve three months after operations than in the cases with a subcutaneous transposition, respectively 10.9 mm2 and 12 mm2. Patients satisfaction measured with the DASH questionnaire and the VAS scale showed that there was a statistically significant improvement after both operations. Conclusions. According to our results, both methods help patients to relieve their symptoms, but after a simple decompression, recovery, measured with patients’ self-reporting instruments and with ultrasound examination, is faster.
Antibacterial evaluation of bioactive modifiers of bone cements: antibiotics, nanometals and chitosan
- Marcin Wekwejt
- Anna Pałubicka
- Beata Świeczko-Żurek
2018 Pełny tekst European Journal of Medical Technologies
Modern biomaterials in addition to their basic tasks, can serve as carriers of active substance. The release of a bioactive particles allows to locally fight infection or its prevent it. Bone cements additionally to their basic applications in orthopedic surgery can also serve to deliver locally active substances. Currently, only antibiotics are routinely used as modifiers for bone cements. Bioactive bone cements constitute a constantly growing group of biomaterials. In this work, analysis of the bactericidal effectiveness of selected bioactive substances used as cement modifiers was performed. Specimens of PMMA bone cement with the following additives were prepared: antibiotics (gentamicin and ciprofloxacin), nanometals (nanosilver and nanocopper) and chitosan. Then this specimens were tested in the aspect of combating bacteria. The bacterial growth inhibition zone for a medium composed of three hospital strains: Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli was measured. The efficacy of bone cements containing antibiotics or nanometals has been confirmed. It is assumed that the use of bone cements as carriers of active substances is possible.
Antibacterial polyurethanes, modifed with cinnamaldehyde, as potential materials for fabrication of wound dressings
- Justyna Kucińska-Lipka
- Iga Gubańska
- Alicja Lewandowska
- Agata Terebieniec
- Agnieszka Haryńska
- Hubert Cieśliński
2018 Pełny tekst POLYMER BULLETIN
The epidermis is a skin layer, which protects an organism from the different factors of external environment. Therefore, the fast and effective regeneration of epidermis is important. Potential materials used for epidermis regeneration may be polyurethane scaffolds in form of the thin permeable layers. One and main disadvantage of such polyurethane scaffolds are their lack of antibacterial and antifungal properties. The great proposition to improve antiseptic properties of polyurethane epidermis scaffolds is to modify them with the use of substances, which reveal antiseptic, antimicrobial, and/or antifungal properties like cinnamaldehyde (CA). The great advantage speaking in favor of this compound is the fact that it has been approved and concerned as generally safe by the Food and Drug Administration in the USA. In this paper was described the fabrication of antibacterial microporous polyurethane scaffolds (MPTLs) in a form of a thin layers by using solvent-casting/particulateleaching technique combined with thermally induced phase separation. Obtained MPTLs were modified with CA at different concentrations (0.5–5%): to establish the most suitable antibacterial effect of the CA introduced into the MPTLs matrix. Obtained unmodified and CA-modified MPTLs were characterized by mechanical and physicochemical properties as well as by identification of their antibacterial performance. The performed studies revealed that the most relevant antimicrobial effect of CA-modified MPTLs was observed when the CA concentration was 3.5%.
Antifungal Activity and Synergism with Azoles of Polish Propolis
- Katarzyna Magdalena Gucwa
- Barbara Kusznierewicz
- Sławomir Milewski
- Patrick Van Dijck
- Piotr Szweda
2018 Pełny tekst Pathogens
The aim of our work was to check if one of the products of natural origin, namely honey 19 bee propolis may be an alternative or supplement to currently used antifungal agents. The activity 20 of 50 ethanolic extracts of propolis (EEPs), harvested in Polish apiaries, was tested on a group of 69 21 clinical isolates of C. albicans. Most of the EEPs showed satisfactory activity, with minimum 22 fungicidal concentrations (MFC) mainly in the range of 0.08-1.25% (v/v). Eradication of biofilm 23 from polystyrene microtitration plates in 50% (MBEC50) required concentrations in the range of 24 0.04% (v/v) to more than 1.25% (v/v). High activity was also observed in eradication of biofilm 25 formed by C. glabrata and C. krusei on the surfaces of PVC and silicone catheters. EEPs at 26 subinhibitory concentrations inhibited yeast-to-mycelia morphological transformation of C. albicans 27 in liquid medium and mycelial growth on solid medium. A synergistic effect was observed for the 28 action of EEPs in combination with fluconazole (FLU) and voriconazole (VOR) against C. albicans. 29 In the presence of EEP at concentration as low as 0.02%, the MICs of FLU and VOR were 256 to 32 30 times lower in comparison to those of the drug alone. Evidences for the fungal cell membrane as 31 the most probable target of EEPs are presented.
Antifungal dipeptides incorporating an inhibitor of homoserine dehydrogenase
- Andrzej Stanisław Skwarecki
- Marta Schielmann
- Dorota Martynow
- Marcin Kawczyński
- Aleksandra Wiśniewska
- Maria Jolanta Milewska
- Sławomir Milewski
2018 JOURNAL OF PEPTIDE SCIENCE
The antifungal activity of 5‐hydroxy‐4‐oxo‐L‐norvaline (HONV), exhibited under conditions mimicking human serum, may be improved upon incorporation of this amino acid into a dipeptide structure. Several HONV‐containing dipeptides inhibited growth of human pathogenic yeasts of the Candida genus in the RPMI‐1640 medium, with minimal inhibitory concentration values in the 32 to 64 μg mL−1 range. This activity was not affected by multidrug resistance that is caused by overexpression of genes encoding drug efflux proteins. The mechanism of antifungal action of HONV dipeptides involved uptake by the oligopeptide transport system, subsequent intracellular cleavage by cytosolic peptidases, and inhibition of homoserine dehydrogenase by the released HONV. The relative transport rates determined the anticandidal activity of HONV dipeptides.
Antimicrobial Activity of Chimera Peptides Composed of Human Neutrophil Peptide 1 (HNP-1) Truncated Analogues and Bovine Lactoferrampin
- Natalia Ptaszyńska
- Katarzyna Magdalena Gucwa
- Anna Łęgowska
- Dawid Dębowski
- Agata Gitlin-Domagalska
- Jan Jakub Lica
- Mateusz Heldt
- Dorota Martynow
- Mateusz Olszewski
- Sławomir Milewski
- Tzi Ng
- Krzysztof Rolka
2018 BIOCONJUGATE CHEMISTRY
Three chimera peptides composed of bovine lactoferrampin and the analogue of truncated human neutrophil peptide 1 were synthesized by the solid-phase method. In two compounds peptide chains were connected via isopeptide bond, whereas in the third one disulfide bridge served as a linker. All three chimeras displayed significantly higher antimicrobial activity than the constituent peptides as well as their equimolar mixtures. The one with a disulfide bridge displayed selectivity toward Gram-positive bacteria and was able to penetrate bacterial cells. The chimeric peptides demonstrated low in vitro mammalian cytotoxicity, especially against benign cells. The significance of linker type was also reflected in the secondary structure and proteolytic stability of studied compounds. Presented results proved that such chimeras are good lead structures for designing antimicrobial drugs.
Antioxidant properties of ferrous flavanol mixtures
- Michalina Grzesik
- Grzegorz Bartosz
- Andrzej Dziedzic
- Dorota Narog
- Jacek Namieśnik
- Izabela Sadowska-Bartosz
2018 FOOD CHEMISTRY
Interaction of metal, especially iron ions with flavanols is considered as an important feature of these compounds and is believed to contribute to their both antioxidant and prooxidant properties. The aim of this study was to examine how Fe2+ binding to form a 4:1 (flavanol:Fe2+) mixtures affects the antioxidant properties of flavanols. ABTS∗ scavenging, protection against fluorescence bleaching induced by AAPH and hypochlorite, protection against lipid peroxidation and protection against hypochlorite-induced hemolysis demonstrated that flavonol-Fe2+ mixtures retain antioxidant properties, although, in most cases, they are lower with respect to the flavanols alone. No superoxide dismutase-like or catalase-like activity of the mixtures was revealed.
Aparat słuchowy a alternatywne urządzenia poprawiające słyszenie
- Tomasz Poremski
- Piotr Szymański
- Bożena Kostek
2018 Otorynolaryngologia - Przegląd Kliniczny
W opracowaniu dokonano przeglądu dostępnych prac dotyczących różnych rodzajów urządzeń poprawiających słyszenie, które w szczególnych przypadkach mogą być traktowane jako rozwiązania alternatywne w stosunku do klasycznych aparatów słuchowych. Praca zawiera dyskusję na temat nowego rodzaju aparatu słuchowego wstępnie zaprogramowanego, który może być dystrybuowany korespondencyjnie lub bezpośrednio potencjalnym użytkownikom. Ponadto zawarto opis tzw. „personalnych” wzmacniaczy dźwięku ze szczególnym uwzględnieniem tzw. wzmacniaczy słuchu, które co do zasady są przeznaczone dla osób ze słuchem normalnym. Podano cechy poszczególnych rozwiązań oraz możliwe zastosowania. Analiza dostępnych opracowań w tym zakresie pokazuje dużą różnorodność rozwiązań, a co za tym idzie brak jednoznacznych kryteriów, dzięki którym można by dokonać łatwej i obiektywnej oceny urządzeń między sobą czy też porównać je z klasycznymi aparatami słuchowymi. Na podstawie przedstawionej pracy można sfomułować następujące wnioski: wzmacniacze słuchu nie powinny być stosowane w przypadku niedosłuchów odbiorczych czuciowo-nerwowych z uwagi na brak możliwości właściwego dostosowania parametrów akustycznych takiego wzmacniacza do specyficznej charakterystyki niedosłuchu. Wysoki poziom ciśnienia akustycznego, jaki mogą one generować może pogłębiać wadę słuchu. Aparaty słuchowe wstępnie zaprogramowane mogą stanowić alternatywę dla klasycznych aparatów, choć wyniki badań pokazują, że uzyskiwane efekty, w szczególności w rozumieniu mowy, są słabsze. Kluczową rolę w poprawie możliwości uzyskania bardziej efektywnych wyników w przypadku niedosłuchu odbiorczego pełni audiolog lub protetyk słuchu.
Aplikacje i usługi a technologie sieciowe
- Henryk Krawczyk
- Sylwester Kaczmarek
- Krzysztof Nowicki
2018
Obserwując tempo rozwoju technologii sieciowych oraz usług i aplikacji stajemy przed ogromnym dylematem jak wykorzystać istniejące możliwości by modernizować wybrane usługi i aplikacje zgodnie z ciągle zmieniającymi się potrzebami użytkowników. Bardzo często sygnalizowane nowe technologie czy aplikacje mają jednak czysto charakter biznesowy podporządkowany prawom marketingu i nie wnoszą wielu istotnych zmian. Dlatego jest ważne zrozumienie realnych trendów rozwojowych, znaczenia wprowadzanych innowacyjnych rozwiązań czy zauważenie rzeczywistych i obiecujących nowych obszarów nauki i techniki. Niniejsza monografia wychodzi temu naprzeciw. Zwraca bowiem uwagę na: 1. rolę komitetów normalizacyjnych podejmujących próby opracowania wzorcowych rozwiązań, 2. aktualne trendy rozwojowe sieci telekomunikacyjnych i systemów informatycznych, a także na przydatność kluczowych technologii w przyszłości, w tym zorientowanie się na interaktywność, mobilność, multimedialność, skalowalność czy bezpieczeństwo, 3. potrzebę ujednolicenia nazewnictwa (stosowanej terminologii - chociażby w przypadku aplikacji i usług), wprowadzenie wielu polskich odpowiedników nazw angielskich w celu precyzyjnego opisu realizowanych przedsięwzięć, 4. kierunki rozwoju technologii w celu dalszego polepszania jakości funkcjonowania usług i aplikacji wykorzystywanych w przeróżnych dziedzinach życia, 5. praktyczną przydatność wybranych i opisanych w monografii zintegrowanych rozwiązań, odnoszących się trójwarstwowego modelu: od infrastruktury sieciowej poprzez różnego typu usługi do aplikacji dostępnych różnorodnym użytkownikom. W monografii ograniczono rozważania do technologii sieciowej IP oraz VoIP związanych z rozwojem sieci nowej generacji (NGN), gdzie kolejne warstwy mogą być rozwijane niezależnie. Natomiast usługi i aplikacje są implementowane w technologiach internetowych (WWW – World Wide Web), co zwiększa uniwersalność rozwiązań oraz powszechność ich zastosowań.
Applicability of Emotion Recognition and Induction Methods to Study the Behavior of Programmers
- Michał Wróbel
2018 Pełny tekst Applied Sciences-Basel
Recent studies in the field of software engineering have shown that positive emotions can increase and negative emotions decrease the productivity of programmers. In the field of affective computing, many methods and tools to recognize the emotions of computer users were proposed. However, it has not been verified yet which of them can be used to monitor the emotional states of software developers. The paper describes a study carried out on a group of 35 articipants to determine which of these methods can be used during programming. During the study, data from multiple sensors that are commonly used in methods of emotional recognition were collected. The participants were extensively questioned about the sensors’ invasiveness during programming. This allowed us to determine which of them are applicable in the work of programmers. In addition, it was verified which methods are suitable for use in the work environment and which are only suitable in the laboratory. Moreover, three methods for inducing negative emotions have been proposed, and their effectiveness has been verified.
Application and mechanical properties of aluminium alloys
- Andrzej Ambroziak
- Maciej Tomasz Solarczyk
2018
The paper presents a short survey of the application and mechanical properties of aluminium alloys. This area of scientific research is still developing, the authors restricted it to about 30 papers. Numerical simulations of the aluminium bracket are also investigated. The authors propose a solution to increase the load capacity of aluminium brackets with application of the additional cover plates. This study is proposed as an introduction to a comprehensive investigation of mechanical properties of aluminium brackets.
Application of Electrochemical Impedance Spectroscopy to evaluate cathodically protected coated steel in seawater
- Michał Narożny
- Krzysztof Żakowski
- Kazimierz Darowicki
2018 Pełny tekst CONSTRUCTION AND BUILDING MATERIALS
Two types of organic coated carbon steel (S235JR2 grade) electrodes were exposed to artificial seawater environment. One prepared type was defect free while the other one had an intentionally introduced φ0,5 cm coating defect. Both kinds of samples were polarized during the exposure to four potentials corresponding to four different cathodic protection levels. Evolution of their EIS spectra is presented in this paper. Results obtained in the experiment indicate that protective organic coating condition could be estimated and monitored in time based on EIS investigations. If a sample is defected EIS allows a recognition of overprotected and unprotected sample. Distinguishing a fully protected sample from partially protected sample based on EIS was troublesome.
Application of Electronic Nose to Ambient Air Quality Evaluation With Respect to Odour Nuisance in Vicinity of Municipal Landfills and Sewage Treatment
- Jacek Gębicki
- Bartosz Szulczyński
- Hubert Byliński
- Paulina Kolasińska
- Tomasz Dymerski
- Jacek Namieśnik
2018 Pełny tekst
This chapter contains information about application of the electronic nose type instruments to evaluation of ambient air odour quality connected with such sectors of human activity as municipal landfills or sewage treatment plants. The authors present potential sources of emission from these sectors, characterize the chemical compounds responsible for presence of unpleasant odours, describe the influence of those compounds on human health and related discomfort. Legal aspects pertaining to admissible odour concentration levels in selected countries are also presented. The chapter describes instrumental and sensory methods utilized for determination of odour concentration, odour intensity, or hedonic quality. The chemical sensors potentially and currently employed in the electronic nose type devices are also characterized. Moreover, the future prospects of application of the electronic nose instruments to evaluation of ambient air with respect to odour nuisance are discussed.
Application of electronic nose to effectiveness monitoring of air contaminated with toluene vapors biofiltration process
- Bartosz Szulczyński
- Piotr Rybarczyk
- Jacek Gębicki
2018 Pełny tekst
The research presents the application of electronic nose (combined with MLR model) to on-line effectiveness monitoring of biofiltration of air contaminated with hydrophobic, odorous compound (toluene vapors). The research was conducted using two-section biotrickling filter inhabited by Candida environmental isolates. Gas chromatography was used as the comparative technique to obtain reliable quantification of toluene concentration in the samples. After about 200 hours of the process, a removal efficiency of 49% was obtained.
Application of fuzzy logic to determine the odour intensity of model gas mixtures using electronic nose
- Bartosz Szulczyński
- Jacek Gębicki
- Jacek Namieśnik
2018 Pełny tekst E3S Web of Conferences
The paper presents the possibility of application of fuzzy logic to determine the odour intensity of model, ternary gas mixtures (α-pinene, toluene and triethylamine) using electronic nose prototype. The results obtained using fuzzy logic algorithms were compared with the values obtained using multiple linear regression (MLR) model and sensory analysis. As the results of the studies, it was found the electronic nose prototype along with the fuzzy logic pattern recognition system can be successfully used to estimate the odour intensity of tested gas mixtures. The correctness of the results obtained using fuzzy logic was equal to 68%.
Application of gas chromatography–tandem mass spectrometry for the determination of amphetamine-type stimulants in blood and urine
- Mateusz Kacper Woźniak
- Marek Wiergowski
- Justyna Aszyk
- Paweł Kubica
- Jacek Namieśnik
- Marek Biziuk
2018 Pełny tekst JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
Amphetamine, methamphetamine, phentermine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and 3,4-methylenedioxy-N-ethylamphetamine (MDEA) are the most popular amphetamine-type stimulants. The use of these substances is a serious societal problem worldwide. In this study, a method based on gas chromatography-tandem mass spectrometry (GC-MS/MS) with simple and rapid liquid-liquid extraction (LLE) and derivatization was developed and validated for the simultaneous determination of the six aforementioned amphetamine derivatives in blood and urine. The detection of all compounds was based on multiple reaction monitoring (MRM) transitions. The most important advantage of the method is the minimal sample volume (as low as 200 µL) required for the extraction procedure. The validation parameters, i.e., the recovery (90.5-104%), inter-day accuracy (94.2-109.1%) and precision (0.5-5.8%), showed the repeatability and sensitivity of the method for both matrices and indicated that the proposed procedure fulfils internationally established acceptance criteria for bioanalytical methods. The procedure was successfully applied to the analysis of real blood and urine samples examined in 22 forensic toxicological cases. To the best of our knowledge, this is the first work presenting the use of GC-MS/MS for the determination of amphetamine-type stimulants in blood and urine. In view of the low limits of detection (0.09-0.81 ng/ml), limits of quantification (0.26-2.4 ng/mL), and high selectivity, the procedure can be applied for drug monitoring in both fatal and non-fatal intoxication cases in routine toxicology analysis.
Application of guided waves in the evaluation of steel-concrete adhesive connection
- Magdalena Rucka
- Beata Zima
2018
The aim of the paper is the application of guided waves in the evaluation of a condition state of adhesive connection between steel and concrete. The study concerns a push-out specimen consisting of two steel plates glued to opposite faces of a concrete cube with the use of structural adhesive. Wave propagation in the specimen without external load is investigated both experimentally and numerically. The second stage of the investigation is the wave propagation analysis at various states of mechanical degradation during the push-out test. The obtained results are evaluated in terms of a possible application of guided waves for inspection of adhesive bonding in steel-concrete systems.
Application of lightweight cement composite with foamed glass aggregate in shell structures
- Marzena Kurpińska
- Tomasz Ferenc
2018
The purpose of the paper is to investigate the abilities of applying Granulated Expanded Glass Aggregate (GEGA) as a natural volume substitute of aggregate as a component of lightweight concrete. The GEGA aggregates used in the experiments were made of confused glass waste. In order to achieve satisfactory strength of concrete Granulated Ash Aggregate (GAA) was added as well. To produce specimens three grain sizes of aggregates was used: 2 mm – GEGA, 4 mm – GEGA and 8 mm GAA. The influence was assessed of percentage participation of each aggregate in whole composite (0%, 25%, 50%, 75%, 100%) on the properties of lightweight concrete mix, on mechanical properties of lightweight concrete and its practical usage in thin shells. The series of 15 concrete mixes were prepared for various aggregate contents and for constant water-cement ratio (w/c=0.5).
Application of molecularly imprinted polymers in analytical chiral separations and analysis
- Małgorzata Rutkowska
- Justyna Płotka-Wasylka
- Calum Morrison
- Piotr Paweł Wieczorek
- Jacek Namieśnik
- Mariusz Marć
2018 Pełny tekst TRAC-TRENDS IN ANALYTICAL CHEMISTRY
Over the last two decades the process of development and application of a new types of molecular imprinted polymer (MIP) sorbents in the field of analytical chemistry have been widely described in the literature. One of the new trends in analytical chemistry practice is the use of new types of MIP sorbents as specific sorption materials constituting the stationary phase in advanced separation techniques. The following review paper contains comprehensive information about the application of a specific and well defined MIP sorbents (with the data base in the paper about the reagents used in MIP preparation process) as stationary phases in separation techniques including high performance liquid chromatography and capillary electrochromatography. Coverage includes newly created types of stationary phases (MIP sorbents) used for chiral recognition, with the focus on applications in enantioselective separation.
Application of Multivariate Analysis Methods in Welding Engineering
- Dariusz Fydrych
- Aleksandra Świerczyńska
- Grzegorz Rogalski
- Jerzy Łabanowski
2018 Pełny tekst Biuletyn Instytutu Spawalnictwa w Gliwicach
Phenomena and processes taking place during welding are usually very complex and, for this reason, should be described using multivariate methods. The article discusses the methodological basis and selected application areas as regards the solving of welding problems using statistical multivariate methods. In addition, the article presents exemplary applications of the design of experiment, multiple regression analysis, cluster analysis, principal component analysis and logistic regression analysis. The application of multivariate analyses provides the possibility of performing the mathematical description of joining processes, which, after verification, could be used to forecast results of such processes, particularly in relation to the properties and fatigue service life of welded structures.