Wyniki wyszukiwania - BazTech

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Impedance Sensors Made in PCB and LTCC Technologies for Monitoring Growth and Degradation of Pseudomonal Biofilm

Chabowski K., Junka A. F., Piasecki T., Nowak D., Nitsch K., Smutnicka D., Bartoszewicz M., Moczała M., Szymczyk P.

Metrology and Measurement Systems

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2017

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Vol. 24, nr 2

369--380

EN

The suitability of low-cost impedance sensors for microbiological purposes and biofilm growth monitoring was evaluated. The sensors with interdigitated electrodes were fabricated in PCB and LTCC technologies. The electrodes were golden (LTCC) or gold-plated (PCB) to provide surface stability. The sensors were used for monitoring growth and degradation of the reference ATCC 15442 Pseudomonas aeruginosa strain biofilm in invitro setting. During the experiment, the impedance spectra of the sensors were measured and analysed using electrical equivalent circuit (EEC) modelling. Additionally, the process of adhesion and growth of bacteria on a sensor’s surface was assessed by means of the optical and SEM microscopy. EEC and SEM microscopic analysis revealed that the gold layer on copper electrodes was not tight, making the PCB sensors susceptible to corrosion while the LTCC sensors had good surface stability. It turned out that the LTCC sensors are suitable for monitoring pseudomonal biofilm and the PCB sensors are good detectors of ongoing stages of biofilm formation.

2

The chemical digestion of Ti6Al7Nb scaffolds produced by Selective Laser Melting reduces significantly ability of Pseudomonas aeruginosa to form biofilm

Junka A. F., Szymczyk P., Secewicz A., Pawlak A., Smutnicka D., Ziółkowski G., Bartoszewicz M., Chlebus E.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 1

115--120

EN

In our previous work we reported the impact of hydrofluoric and nitric acid used for chemical polishing of Ti-6Al-7Nb scaffolds on decrease of the number of Staphylococcus aureus biofilm forming cells. Herein, we tested impact of the aforementioned substances on biofilm of Gram-negative microorganism, Pseudomonas aeruginosa, dangerous pathogen responsible for plethora of implant-related infections. The Ti-6Al-7Nb scaffolds were manufactured using Selective Laser Melting method. Scaffolds were subjected to chemical polishing using a mixture of nitric acid and fluoride or left intact (control group). Pseudomonal biofilm was allowed to form on scaffolds for 24 hours and was removed by mechanical vortex shaking. The number of pseudomonal cells was estimated by means of quantitative culture and Scanning Electron Microscopy. The presence of nitric acid and fluoride on scaffold surfaces was assessed by means of IR and rentgen spetorscopy. Quantitative data were analysed using the Mann–Whitney test (P ≤ 0.05). Our results indicate that application of chemical polishing correlates with significant drop of biofilm-forming pseudomonal cells on the manufactured Ti-6Al-7Nb scaffolds ( p = 0.0133, Mann–Whitney test) compared to the number of biofilm-forming cells on non-polished scaffolds. As X-ray photoelectron spectroscopy revealed the presence of fluoride and nitrogen on the surface of scaffold, we speculate that drop of biofilm forming cells may be caused by biofilm-supressing activity of these two elements.

3

The ability of S.aureus to form biofilm on the Ti-6Al-7Nb scaffolds produced by Selective Laser Melting and subjected to the different types of surface modifications

Szymczyk P., Junka A., Ziółkowski G., Smutnicka D., Bartoszewicz M., Chlebus E.

Acta of Bioengineering and Biomechanics

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2013

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Vol. 15, no. 1

69--76

EN

The Gram-positive coccus, Staphylococcus aureus, is the leading etiologic agent of limb and life-threatening biofilm-related infections in the patients following the orthopaedic implantations. The aim of the present paper is to estimate the ability of S. aureus to form biofilm on titanium alloy (Ti-6Al-7Nb) scaffolds produced by Selective Laser Melting (SLM) and subjected to the different types of surface modifications, including ultrasonic cleaning and chemical polishing. The results obtained indicate significantly the decreased ability of S.aureus to form biofilm on the surface of scaffolds subjected to the chemical polishing in comparison to the scaffolds cleaned ultrasonically. The data provided can be useful for future applications of the SLM technology in production of Ti-6Al-7Nb medical implants.

4

A study of episodic events in the Baltic Sea - combined in situ and satellite observations

Łysiak-Pastuszak E., Bartoszewicz M., Bradtke K., Darecki M., Drgas N., Kowalczuk P., Kraśniewski W., Krężel A., Krzymiński W., Lewandowski Ł., Mazur-Marzec H., Piliczewski B., Sagan S., Sutryk K., Witek B.

Oceanologia

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2012

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No. 54 (2)

121-141

EN

A project was developed concerning the operational system of surveillance and the recording of episodic events in the Baltic Sea. In situ information was to be combined with multi-sensory satellite imagery to determine the extent of algal blooms, to track their evolution and that of rapid environmental events like hydrological fronts. The main element of the system was an autonomous Ferry Box module on a ferry operating between Gdynia and Karlskrona, automatically measuring temperature, salinity and chlorophyll a fluorescence. At pre-selected locations, discrete water samples were collected, which were subsequently analysed for their phytoplankton content, and algal hepato- and neurotoxins; they were also used in toxicity tests with Artemia franciscana.

5

Bakteriologiczne zanieczyszczenie wywołane opadami

Michalska M., Bartoszewicz M., Cieszyńska M., Nowacki J.

Wodociągi - Kanalizacja

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2010

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nr 4

50-50

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Badania nad technologią oczyszczania wód balastowych

Modrzejewska H., Walk Walk., Bartoszewicz M., Michalska M.

Ekologia i Technika

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2009

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R. 17, nr 1

9-17

PL

Wody balastowe zawierają liczne organizmy należące do różnych formacji ekologicznych (planktonu, neustonu, nektonu i bentosu) będących przedstawicielami gatunków charakterystycznych w miejscu pobierania wody. Organizmy te zrzucane wraz z wodami balastowymi w innych portach stanowią realne i udowodnione zagrożenie dla lokalnych ekosystemów, jak i dla ludzi żyjących w strefie przybrzeżnej. W artykule przedstawiono wyniki badań w skali laboratoryjnej wybranych metod oczyszczania wód balastowych z grupy metod chemicznych i fizycznych. Badania prowadzono na organizmach wzorcowych. Określono skuteczność preparatu biobójczego Unisteryl jako środka mogącego mieć zastosowanie do chemicznego oczyszczania wód balastowych w zależności od stężenia preparatu, zasolenia wody, czasu kontaktu i temperatury. Zbadano wpływ ultradźwięków jako fizycznej metody unieszkodliwiania organizmów planktonowych w funkcji amplitudy drgań i czasu. Stwierdzono, że stężenie 50ppm preparatu Unisteryl jest odpowiednie dla unieszkodliwienia bakterii i zooplanktonu oraz mało skuteczne dla przedstawiciela fitoplanktonu. Ultradźwięki okazały się 100% skuteczne dla zooplanktonu, natomiast nie stwierdzono działania dezintegrującego na fitoplankton i bakterie w zadanych parametrach czasu i amplitudy. Przeprowadzone badania stanowią pierwszy etap, w mikroskali, działań prowadzących do opracowania wielostopnlowego (filtracja, oczyszczanie chemiczne i ultradźwięki) systemu oczyszczania wód balastowych na statkach z zastosowaniem preparatu aktywnego.

EN

Ballast water contains numerous organisms belonging to different ecological formations (plankton, neuston, nekton and benthos) which represent species characteristic for the place of water intake. These organisms discharged with ballast water in other ports create a real and proven danger for local ecosystems and people living in coastal area. This paper presents results of investigations, in laboratory scale, on selected chemical and physical methods of ballast water treatment. The investigations were conducted on selected standard organisms. Effectiveness of biolethal preparation Unisteryl which could be applied as an agent for chemical treatment of ballast water was determined in dependence on the preparation concentration, water salinity, period of contact and temperature. Effect of ultrasounds, as a physical method of plankton organisms killing versus time and vibrations amplitude was investigated. It was found, that Unisteryl in concentration of SOppm is sufficient to kill bacteria and zoo-plankton but is not very effective for phytoplankton. Ultrasounds are effective in 100% for zooplankton but their disintegrating action on phytoplankton and bacteria is insufficient. Performed studies are the first stage, in microscale of works leading to development of multistage system (filtration, chemical treatment and ultrasounds) of ballast water treatment on ship with the use of an active preparation.

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Badania jakości wód balastowych zrzucanych w Zatoce Gdańskiej

Walk M., Modrzejewska H., Rybicka D., Opioła R., Michalska M., Bartoszewicz M.

Inżynieria Morska i Geotechnika

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2007

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nr 2

60-69

PL

Pobieranie próbek wód balastowych. Zakres metody badań, oznaczenia fizykochemiczne, biologiczne, mikrobiologiczne i wyniki badań. Wnioski.

EN

Sampling of ballast waters. Scope of testing method, physico-chemical, biological, microbiological determination and test results. Conclusions.

8

Zmiany stanu sanitarnego kąpielisk morskich położonych w granicach administracyjnych Gdańska w latach 1993 - 2002.

Szumilas T., Michalska M., Bartoszewicz M., Nowacki J.

Inżynieria Morska i Geotechnika

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2004

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nr 3

131-138

PL

Ocena stanu sanitarnego przybrzeżnych wód morskich Zatoki Gdańskiej pod kątem przydatności wód do kąpieli. Wyraźna poprawa stanu sanitarnego wód w roku 1997, aod 2000 r. tendencja do poprawy tego stanu. Od 2000 r. stan sanitarny badanych wód nie budzi zastrzeżeń.

EN

An assessment of sanitary conditions of nearshore waters in Gdańsk Bay for its use for recreations purposes. Essential improvement of sanitary quality of waters observed in 1997 and since 2000 the tendency for its further improvement. Since that time the quality of water meets respective requirements for bathe.