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1
Content available remote Mikrofalowy generator losowych ciągów binarnych – konstrukcja, oprogramowanie i dowód bezpieczeństwa
Leśniewicz Marek, Komorowski Piotr, Zabłocki Janusz
Przegląd Elektrotechniczny
|
2023
|
R. 99, nr 5
68--76
PL
W artykule przedstawiono opis elektronicznych i programistycznych rozwiązań sprzętowego, mikrofalowego generatora losowych ciągów binarnych o przepływności wyjściowej 1 Gbit/s. Szczególną uwagę poświęcono problemom programowej obsługi procesów przetwarzania ciągów o tak dużej przepływności. Opisano autorską metodę pomiarów i weryfikacji entropii generowanych ciągów oraz przedstawiono warunkowy, kryptograficzny dowód ich bezpieczeństwa.
EN
The article presents a description of electronic and programming solutions for a hardware, microwave random binary sequences generator with an output bit rate of 1 Gbps. Particular attention was paid to the problems of programmatic handling of string processing processes with such a high throughput. Have been described the method of measuring and verifying the entropy of the generated strings and presents a conditional, cryptographic proof of their security.
2
Content available remote Analiza możliwości sprzętowej generacji losowych ciągów binarnych z przepływnością 1 Gbit/s
Leśniewicz Marek, Komorowski Piotr, Zabłocki Janusz
Przegląd Elektrotechniczny
|
2023
|
R. 99, nr 4
207--215
PL
W artykule przedstawiono analizę możliwości sprzętowej generacji doskonale losowych ciągów binarnych z przepływnością 1 Gbit/s, wykorzystującą układy i sygnały mikrofalowe. W analizie użyto powszechnie znanych modeli generacji ciągów losowych, jednak z wykorzystaniem niestosowanych dotąd w tym celu technologii, w tym zastosowania do kreacji ciągów układów programowalnych FPGA. Analizy udokumentowano wynikami pomiarów rzeczywistych układów i sygnałów w funkcji czasu i częstotliwości za pomocą oscyloskopu i analizatora widma w paśmie 2 GHz.
EN
The article presents an analysis of the hardware capabilities of generating truly random binary strings with a bit rate of 1 Gbps, using microwave circuits and signals. The analysis uses commonly known models of random sequence generation, but with the use of technologies that have not been used for this purpose so far, including the use of FPGA programmable circuits for the creation of sequences. The analyzes were documented with the results of measurements of real systems and signals as a function of time and frequency using an oscilloscope and a spectrum analyzer in the 2 GHz band.
3
Content available Experimental investigations of the PMMA bone cement distribution inside a model of lumbar vertebrae
Bonik Artur, Tyfa Zbigniew, Ciupik Lechosław Franciszek, Sobczak Krzysztof, Kierzkowska Agnieszka, Obidowski Damian Stanisław, Witkowski Dariusz, Pałczyński Tomasz, Elgalal Marcin, Komorowski Piotr, Słoński Edward, Jóźwik Krzysztof, Walkowiak Bogdan
Engineering of Biomaterials
|
2022
|
vol. 25, no. 165
23--30
EN
The use of bone cement in procedures such as vertebroplasty and kyphoplasty can reduce pain and mechanically support the spine. This study aimed to evaluate whether air entrapped within bone cement affected its distribution in a vertebral body model. The study included 3D printed anatomical models of vertebrae together with their internal trabecular structure. Aeration was achieved by mixing the bone cement using three different altered procedures, whilst the control sample was prepared according to the manufacturer’s instructions. The further two samples were prepared by reducing or increasing the number of cycles required to mix the bone cement. A test rig was used to administer the prepared bone cement and introduce it into the vertebral model. Each time the injection was stopped when either the cement started to flow out of the vertebral model or when the entire cement volume was administered. The computer tomography (CT) scanning was performed to evaluate aerification and its influence on the bone cement distribution in each of the patient-specific models. The large number of small pores visible within the cement, especially in the cannula vicinity, indicated that the cement should not be treated as a homogenous liquid. These results suggest that a high level of aerification can influence the further cement distribution.
4
Content available remote Metoda i układ powielania ciągów losowych
Leśniewicz Marek, Komorowski Piotr
Przegląd Elektrotechniczny
|
2021
|
R. 97, nr 8
137--141
PL
Przedmiotem pracy są metoda i układ powielania ciągów losowych. Powielanie polega na pseudolosowym próbkowaniu odpowiednio licznej próby ciągu prawdziwie losowego ze źródła w postaci generatora sprzętowego, a następnie na wymianie wykorzystanej próby na następną i skasowaniu próby zużytej. W wyniku powielania otrzymuje się ciągi wynikowe o zadowalających właściwościach probabilistycznych i parametrach statystycznych. Metoda będąca przedmiotem pracy pozwala na powielanie ciągów z generatorów sprzętowych do krotności sięgających 1000.
EN
The subject of the work is the method and system for duplicating random sequences. Reproduction consists in pseudo-random sampling of a sufficiently large sample of a truly random sequence from a source in the form of a hardware generator, and then on the exchange of the used sample for the next one and deletion of the used sample. As a result of duplication, result sequences with satisfactory probabilistic properties and statistical parameters are obtained. The method allows duplication of sequences from hardware generators up to 1000 times.
5
Content available In situ-formed bacterial exopolysaccharide (EPS) as a potential carrier for anchorage-dependent cell cultures
Komorowski Piotr, Kołodziejczyk Agnieszka, Makowski Krzysztof, Kotarba Sylwia, Walkowiak Bogdan
Engineering of Biomaterials
|
2021
|
Vol. 24, no. 159
18--23
EN
The study involved the use of a bacterial strain isolated from environmental samples which produce the biopolymer in the form of pellets in the submerged culture. This material (bacterial exopolysaccharide) is produced by bacteria of the Komogateibacter xylinus which are prevalent in the environment. The aim of this study was to characterize bacterial exopolysaccharides and commercial dextran-based “microcarriers” in terms of their roughness and cell culture effects, including the morphology and viability of the human hybridoma vascular endothelial cell line EA.hy926. The pellets were characterized using scanning electron microscopy (SEM) and atomic for¬ce microscopy (AFM). The resulting structures were used for cell culture of adherent cells (anchorage¬-dependent cells). At the same time, the cultures with commercial, dextran-based “microcarriers” were carried out for comparative purposes. After com¬pletion of the cell culture (24 hours of culture), the cellulose and commercial “carriers” were analyzed using SEM and AFM. Finally, the obtained cell dens¬ities (fluorescence labelling) and their morphological characteristics (SEM) were compared. The obtained results strongly support the applicability of bacterial exopolysaccharide (EPS) in tissue engineering to build innovative 3D scaffolds for cell culture, the more so that it is technologically possible to produce EPS as spatially complex structure
6
Content available Design and manufacture of customized medical implants - final report
Elgalal Marcin, Komorowski Piotr, Makowski Krzysztof, Styczyński Andrzej, Rokita Bożena, Kubiak Tomasz, Sawicki Jacek, Walkowiak Bogdan
Engineering of Biomaterials
|
2021
|
Vol. 24, no. 163
24
7
Content available Morphological and biochemical features of microorganisms inhabiting the surfaces of personalized femoral implants
Leszczewicz Martyna, Gniada Natalia, Makowski Krzysztof, Komorowski Piotr, Walkowiak Bogdan
Engineering of Biomaterials
|
2020
|
Vol. 23, no. 158 spec. iss.
46
8
Content available Microscopic analysis of the nanostructures impact on endothelial cells
Kołodziejczyk Agnieszka Maria, Kucińska Magdalena, Jakubowska Aleksandra, Siatkowska Małgorzata, Sokołowska Paulina, Kotarba Sylwia, Makowski Krzysztof, Komorowski Piotr, Walkowiak Bogdan
Engineering of Biomaterials
|
2020
|
Vol. 23, no. 154
2--8
EN
Nowadays nanostructures are more and more often designed as carriers for drug delivery, especially to improve the drug pharmacokinetics and pharmaco-dynamics. Numerous kinds of nanostructures are considered a good prospect for medical applications thanks to their small size, acceptable biocompatibility and toxicity. Due to the fact that nanotechnology is a new field of science, every nano-scale product must be thoroughly examined regarding its toxicity to the human body. This study provides new insights into effects of exposing endothelial cells to the selected nanostructures. Dendrimers of the fourth generation (PAMAMs), multi-walled carbon nanotubes (MWCNTs) and silver nanoparticles (SNPs) were used to evaluate nanostructures influence on endothelial cells in vitro. The nanostructures were evaluated via transmission electron microscopy and dynamic light scattering technique. The cells previously exposed to the nanostructures were observed and analyzed via the atomic force microscopy and scanning electron microscopy to obtain a quantitative evaluation of the cells morphology. The presence of multi-walled carbon nanotubes and silver nanoparticles on the cells surface was confirmed by the scanning electron microscopy. Our results confirm that the surface association and/or uptake of nanostructures by the cells resulting from physicochemical and biological processes, affect the cells morphology. Morphological changes can be induced by the membrane proteins interaction with nanomaterials, which trigger a sequence of intracel-lular biological processes.
9
Content available May metallic biomaterials used for orthopedic implants promote cancer processes? : preliminary trasriptomics research on human articular chondrocytes.
Walkowiak-Przybyło Magdalena, Walczyńska Marta, Kamińska Marta, Komorowski Piotr, Walkowiak Bogdan
Engineering of Biomaterials
|
2020
|
Vol. 23, no. 158 spec. iss.
32
10
Content available Identification and characterization of microbiological contamination sources in the environment of production of personalized femoral implant
Gniada Natalia, Leszczewicz Martyna, Makowski Krzysztof, Komorowski Piotr, Walkowiak Bogdan
Engineering of Biomaterials
|
2020
|
Vol. 23, no. 158 spec. iss.
47
11
Content available Does surface structuring of metallic materials affect thrombocompatibility?
Kamińska Marta, Walczyńska Marta, Walkowiak-Przybyło Magdalena, Komorowski Piotr, Walkowiak Bogdan
Engineering of Biomaterials
|
2020
|
Vol. 23, no. 158 spec. iss.
33
12
Content available Design and manufacture of customized medical implants - third report
Elgalal Marcin, Komorowski Piotr, Makowski Krzysztof, Styczyński Andrzej, Ulański Piotr, Kubiak Tomasz, Sawicki Jacek, Domżalski Marcin, Walkowiak Bogdan
Engineering of Biomaterials
|
2020
|
Vol. 23, no. 158 spec. iss.
31
13
Materiomika - pomost łączący naukę o materiałach z naukami o życiu
Walkowiak Bogdan, Walkowiak-Przybyło Magdalena, Komorowski Piotr
Laboratorium - Przegląd Ogólnopolski
|
2019
|
nr 2
24--30
PL
Artykuł przedstawia najnowsze trendy w dziedzinie nauk o materiałach i związkach tej dziedziny nauki z naukami o życiu. Prezentuje także potencjalną możliwość wykorzystania komórki jako specyficznego sensora rozpoznającego produkty inżynierii materiałowej i nanotechnologii.
EN
This paper informs about the latest trends in th e field of materials science and the relationships of this field of science with life sciences. It also presents the potential of using a cell as a specific sensor that recognizes the products of materials engineering and nanotechnology.
14
Content available Design and manufacture of customized medical implants - continued
Elgalal Marcin, Komorowski Piotr, Makowski Krzysztof, Styczyński Andrzej, Ulański Piotr, Kubiak Tomasz, Sawicki Jacek, Domżalski Marcin, Walkowiak Bogdan
Engineering of Biomaterials
|
2019
|
Vol. 22, no. 153 spec. iss.
100
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