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  • Detection of Toxoplasma gondii Infection in Small Ruminants: Old Problems, and Current Solutions
    • Lucyna Holec-Gąsior
    • Karolina Sołowińska
    2023 Pełny tekst Animals

    Toxoplasmosis is a parasitic zoonosis of veterinary importance, with implications for public health. Toxoplasma gondii infection causes abortion or congenital disease in small ruminants. Moreover, the consumption of infected meat, cured meat products, or unpasteurized milk and dairy products can facilitate zoonotic transmission. Serological studies conducted in various European countries have shown the high seroprevalence of specific anti-T. gondii antibodies in sheep and goats related to the presence of oocysts in the environment, as well as climatic conditions. This article presents the current status of the detection possibilities for T. gondii infection in small ruminants and their milk. Serological testing is considered the most practical method for diagnosing toxoplasmosis; therefore, many studies have shown that recombinant antigens as single proteins, mixtures of various antigens, or chimeric proteins can be successfully used as an alternative to Toxoplasma lysate antigens (TLA). Several assays based on DNA amplification have been developed as alternative diagnostic methods, which are especially useful when serodiagnosis is not possible, e.g., the detection of intrauterine T. gondii infection when the fetus is not immunocompetent. These techniques employ multicopy sequences highly conserved among different strains of T. gondii in conventional, nested, competitive, and quantitative reverse transcriptase-PCR.

  • Detection of Water on Road Surface with Acoustic Vector Sensor
    • Józef Kotus
    • Grzegorz Szwoch
    2023 Pełny tekst SENSORS

    This paper presents a new approach to detecting the presence of water on a road surface, employing an acoustic vector sensor. The proposed method is based on sound intensity analysis in the frequency domain. Acoustic events, representing road vehicles, are detected in the sound intensity signals. The direction of the incoming sound is calculated for the individual spectral components of the intensity signal, and the components not originating from the observed road section are discarded. Next, an estimate of the road surface state is calculated from the sound intensity spectrum, and the wet surface detection is performed by comparing the estimate with a threshold. The proposed method was evaluated using sound recordings made in a real-world scenario, and the algorithm results were compared with data from a reference device. The proposed algorithm achieved 89% precision, recall and F1 score, and it outperforms the traditional approach based on sound pressure analysis. The test results confirm that the proposed method may be used for the detection of water on the road surface with acoustic sensors as an element of a smart city monitoring system.

  • Determinants of the incidence of non-academic staff in European and US HEIs
    • Alessandro Avenali
    • Cinzia Daraio
    • Joanna Wolszczak-Derlacz
    2023 Pełny tekst HIGHER EDUCATION

    In this article, we contribute to the scant literature covering quantitative studies on the determinants of the non-academic staff incidence in higher education institutions by analysing how the proportion of non-academic staff is related to key features such as size, prestige, year of foundation and financial structure of universities. We apply nonlinear regression analysis to compare HEIs across Europe and the USA, taking into account time and cross-country heterogeneity of the two balanced panel datasets concerning European and American universities over a period of 6 years (2011–2016 for Europe and 2012–2017 for the USA). Evidence suggests that in both Europe and the USA, public and larger (if sufficiently large) as well as more research-oriented units are characterised by a higher proportion of non-academic staff. In Europe, we observe an inverted U-shaped effect of the share of non-personnel expenditure and the foundation year on the proportion of nonacademic staff, while the proportion of non-academic staff decreases with the share of core and third-party funding. For the USA, we obtain similar findings except that the share of core funding and third-party funding is characterised by a U-shaped effect, and the impact of the share of non-personnel expenditure has no empirical effect on the proportion of nonacademic staff. Additionally, we discover that some factors that contribute to the proportion of non-academic staff may constitute indicators of performance, suggesting the need for further research to extend our knowledge on the complex issue of the role played by non-academic staff in university performance.

  • Determinanty stabilności fiskalnej jednostki samorządu terytorialnego
    • Maria Jastrzębska
    2023

    Celem rozdziału jest omówienie istoty i znaczenia stabilności fiskalnej JST oraz dokonanie klasyfikacji jej determinant w podziale na instytucjonalno- -prawne, ekonomiczno-finansowe, społeczne i naturalne, polityczne i organizacyjne, a także zwrócenie uwagi na te z nich, które szczególnie negatywnie oddziałują na stabilność fiskalną JST (w podziale na niezależne i zależne od JST).

  • Determinanty stabilności fiskalnej jednostki samorządu terytorialnego
    • Maria Jastrzębska
    2023 Pełny tekst FINANSE Czasopismo Komitetu Nauk o Finansach PAN

    . Celem rozdziału jest omówienie istoty i znaczenia stabilności fiskalnej JST oraz dokonanie klasyfikacji jej determinant w podziale na instytucjonalno- -prawne, ekonomiczno-finansowe, społeczne i naturalne, polityczne i organizacyjne, a także zwrócenie uwagi na te z nich, które szczególnie negatywnie oddziałują na stabilność fiskalną JST (w podziale na niezależne i zależne od JST)

  • Determination of benzodiazepines and Z-hypnotic drugs in whole blood samples by GC–MS/MS: Method development, validation and application
    • Laura Banaszkiewicz
    • Mateusz Kacper Woźniak
    • Michal Kaliszan
    • Agata Kot-Wasik
    2023 MICROCHEMICAL JOURNAL

    Benzodiazepines (BZDs) and Z-drugs are widely used as anxiolytics, sedative hypnotics, anticonvulsants and muscle relaxants. “Designer benzodiazepines” (DBZDs) are a new psychoactive substance class consisting of benzodiazepine derivatives that are not allowed for medical use and are known for being used recreationally. From a toxicologist standpoint, the huge number of such substances implicate a necessity for developing fast and reliable methods to identify and quantify these substances in biological matrices, especially in blood. In this study, a method based on gas chromatography–tandem mass spectrometry (GC–MS/MS) was developed and validated for the determination of 28 benzodiazepine derivatives and 3 Z- drugs. Liquid–liquid extraction requiring the use of a 0.5 mL sample of whole blood and 1 mL of ethyl acetate was applied. No derivatization was necessary to obtain sensitivity and selectivity. All validation data met the established acceptance criteria in accordance with international forensic toxicology guidelines. The method was linear within the tested range of 1–100 ng/mL, 1–200 ng/mL, 1–250 ng/mL, 5–200 ng/mL and 10–250 ng/mL depending on the analyte. The LOD was in the range of 0.09 to 0.66 ng/mL, while the LOQ was between 1 and 10 ng/mL. The calculated mean accuracy ranged between 85.1% and 114.4% for intraday replicates and between 85.2% and 111.2% for interday replicates. Intraday precision (as CVs) ranged from 0.2% to 12.5%, while interday precision ranged from 2.0% to 14.5%. Recovery was between 83.8% and 111.2%. This study was the first attempt to apply GC–MS/MS for the multianalyte determination of benzodiazepines and Z-drugs without analyte derivatization. The developed method proved to be sensitive, specific, simple and fast. The analysis in MRM mode gives high sensitivity and selectivity. Thus, the presented method can be successfully utilized for clinical and forensic toxicology analysis, for interpretation of results and for the preparation of forensic toxicological opinions for courts of law.

  • Determination of equivalent axle load factors with the use of strain energy of distortion
    • Dawid Ryś
    • Francesco Canestrari
    2023 Pełny tekst Road Materials and Pavement Design

    The paper proposes a new method for calculation of equivalent axle load factors based on the analysis of strain energy of distortion induced in road pavements by traffic loads. The main advantage of the method is the more accurate calculation of the effects of multiple axles and super single versus dual tyres. The methodconsiders the location of critical points, at which strain energy of distortion reaches extreme values. When single axles are considered, the function of equivalent axle load factor takes on the form of the well-known power equation with the exponent ranging from 2.7 to 5.3. It was proved that the damaging effect of triple axles on asphalt pavement is several times higher than the damaging effect of three single axles carrying the same load, but at a greater distance to each other. Due to this fact, traffic load may be significantly underestimated in many pavement design methods.

  • Determination of Glycerol, Propylene Glycol, and Nicotine as the Main Components in Refill Liquids for Electronic Cigarettes
    • Paweł Kubica
    2023 Pełny tekst MOLECULES

    Refill liquids for electronic cigarettes are an important area of research due to the health safety and quality control of such products. A method was developed for the determination of glycerol, propylene glycol, and nicotine in refill liquids using liquid chromatography, coupled with tandem mass spectrometry (LC-MS/MS) in multiple reaction monitoring (MRM) mode with electrospray ionisation (ESI). Sample preparation was based on a simple dilute-and-shoot approach, with recoveries ranging from 96 to 112% with coefficients of variation < 6.4%. Linearity, limits of detection and quantification (LOD, LOQ), repeatability, and accuracy were determined for the proposed method. The proposed sample preparation and the developed chromatographic method using hydrophilic interaction liquid chromatography (HILIC) were successfully applied for the determination of glycerol, propylene glycol, and nicotine in refill liquid samples. For the first time, the developed method using HILIC-MS/MS has been applied for the determination of the main components of refill liquids in a single analysis. The proposed procedure is rapid and straightforward and is suitable for quick determination of glycerol, propylene glycol, and nicotine. The nicotine concentrations corresponded to the labelling of samples (it varied from <LOD—11.24 mg/mL), and the ratios of propylene glycol to glycerol were also determined.

  • Determination of Liquid Detergent Pods as a Potential Microplastic Source
    • Karolina Gwizdała
    • Paweł Szarlej
    • Przemysław Gnatowski
    • Edyta Piłat
    • Maciej Sienkiewicz
    • Justyna Kucińska-Lipka
    2023 Pełny tekst Chemistry & Chemical Technology

    Washing pods became a popular way to add detergent to washing machines. Despite the claims about the degradability of the pod film, the sludge in pipes can be observed after the usage of such pods. This study focused on a quantitative and qualitative analysis of washing pod films as a source of microplastic.

  • Determination of t8/5 cooling times for underwater local dry welding of steel
    • Grzegorz Rogalski
    • Aleksandra Świerczyńska
    • Dariusz Fydrych
    2023 MARINE STRUCTURES

    Knowledge of thermal history is the basic condition for studying the structure - properties of welded joints. The determinant of thermal history is the thermal cycle, whose in-situ measurements are still a big challenge. Water as the welding environment complicates this issue even more. The article presents a method to determine an equation for calculating t8/5 cooling times for underwater gas metal arc welding of unalloyed steels using the local dry cavity method. The work uses the contact method of temperature measurements with the use of thermocouples to obtain the temperature changes of the points of welded joints covered by the thermal field. On this basis, the values of the t8/5 cooling times were determined. A regression analysis of the Response Surface Method was used to determine the equation, which resulted in a second-order model with interactions. Statistically significant factors were determined (thickness of welded elements and heat input value) and the model veracity was confirmed as the assumptions of normality and homogeneity of variance (homoscedasticity) of the residuals were met. The t8/5 cooling time values depend on the thickness of the welded elements and heat input value in a nonlinear way. In terms of the test conditions, the cooling times ranged from 3.0 to 7.7 s. The equation allowed for the calculation of t8/5 cooling times during underwater welding of unalloyed steels using the local dry cavity method based on the variability of the experimental conditions with satisfactory accuracy.

  • Determination of the Major By-Products of Citrus hystrix Peel and Their Characteristics in the Context of Utilization in the Industry
    • Martyna Lubinska-Szczygeł
    • Anna Kuczyńska-Łażewska
    • Małgorzata Rutkowska
    • Żaneta Polkowska
    • Elena Katrich
    • Shela Gorinstein
    2023 Pełny tekst MOLECULES

    Kaffir lime (Citrus hystrix) is a popular citrus in Southeast Asia. Despite the growing interest in the peel of the fruit, the leaves are the most frequently used part of the fruit. The aim of the study was to determine the main by-products of the peel, such as pectins, minerals, essential oil, and bioactive compounds, and to evaluate the possibility of using them in various branches of industry. In the study of the essential oil obtained by hydrodistillation performed using the TGA chromatography technique (GC-MS), sabinene (31.93%), β-pinene (26%), and limonene (19%) were selected as the most abundant volatile compounds. Nine microelements (Fe, Zn, Cu, Mn, Co, Ni, Cr, Mo, and V), four macroelements (Mg, Ca, K, and Na), and seven ballast substances (Cd, Hg, Pb, Al, V, Sr, and Pt) were also determined using the microwave plasma-atomic emission spectrometry technique (MP-AES). In the case of microelements, iron 32.72 ± 0.39 mg/kg DW (dry weight) had the highest concentration. In the case of macroelements, the calcium content was 9416 ± 34 mg/kg DW. Optimization of the pectin extraction was also performed by selecting citric acid and obtaining a yield of 7.6–17.6% for acid extraction and 9.9–28.2% for ultrasound-assisted extraction (UAE), depending on the temperature used. The obtained pectins were characterized by the degree of methylation, galacturonic acid content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, and DSC (differential scanning calorimetry) analysis. Among bioactive compounds, the contents of polyphenols (22.63 ± 2.12 mg GAE/g DW), flavonoids (2.72 ± 0.25 mg CE/g DW, vitamin C (2.43 ± 0.19 mg Asc), xantoproteins + carotenes (53.8 ± 4.24 ug), anthocyanins (24.8 ± 1.8 mg CGE/kg DW), and chlorophylls A and B (188.5 ± 8.1, 60.4 ± 3.23 µg/g DW) were evaluated. Antioxidant capacity using (cupric ion-reducing antioxidant capacity) CUPRAC and DPPH assays was also provided with the results of 76.98 ± 8.1, and 12.01 ± 1.02 µmol TE/g DW, respectively.

  • Developing Materials for Biodegradable Otolaryngological Stents
    • Marta Razimowicz
    • Przemysław Gnatowski
    • Paweł Szarlej
    • Edyta Piłat
    • Maciej Sienkiewicz
    • Justyna Kucińska-Lipka
    2023 Pełny tekst Chemistry & Chemical Technology

    Materials for otolaryngological stents have to be characterized by good tensile strength, wear resistance, biocompatibility, and specific degradation time. This work aimed to synthesize polyurethanes based on various biodegradable polyol blends. Their biodegradability and mechanical properties were tested and compared to commercial BIOFLEX material.

  • Development and application of asphalt binder relaxation test in different dynamic shear rheometers
    • Johannes Büchner
    • Dawid Ryś
    • Stefan Trifunović
    • Michael P. Wistuba
    2023 CONSTRUCTION AND BUILDING MATERIALS

    In this study, a novel relaxation test is proposed to evaluate asphalt binder low temperature properties using a Dynamic Shear Rheometer (DSR) with parallel plates of 4 mm in diameter. Three rheometers from three different manufacturers are used to analyze seven asphalt binders. Different material parameters are derived which are useful to evaluate and discriminate different asphalt binders. Test results of all three instruments from different manufacturers are judged identical. Finally, results are compared to results from low temperature tests using a Bending Beam Rheometer (BBR) and a linear correlation is identified for the characteristic m-value from BBR testing.

  • Development and evaluation of RADA-PDGF2 self-assembling peptide hydrogel for enhanced skin wound healing
    • Milena Deptula
    • Joanna Sawicka
    • Piotr Sass
    • Paweł Sosnowski
    • Przemyslaw Karpowicz
    • Małgorzata Zawrzykraj
    • Anna Wardowska
    • Anna Tymińska
    • Maria Dzierżyńska
    • Zuzanna Pietralik-Molińska
    • Barbara Peplińska
    • Jacek Zielinski
    • Karolina Kondej
    • Maciej Kozak
    • Paweł Sachadyn
    • S. Rodziewicz-Motowidło
    • Michal Pikula
    2023 Pełny tekst Frontiers in Pharmacology

    Background: Wound healing complications affect numerous patients each year, creating significant economic and medical challenges. Currently, available methods are not fully effective in the treatment of chronic or complicated wounds; thus, new methods are constantly sought. Our previous studies showed that a peptide designated as PDGF2 derived from PDGF-BB could be a promising drug candidate for wound treatment and that RADA16-I can serve as a release system for bioactive peptides in wound healing. Based on that, in this work, we designed a new self-assembling hydrogel RADA-PDGF2, connecting both peptides by a sequence specific for neutrophil elastase, and evaluated its activity in wound healing. Methods: The physicochemical properties of the designed scaffold were analyzed using transmission electron microscopy, atomic force microscopy, cryoSEM microscopies, and circular dichroism spectroscopy. The enzymatic cleavage was performed using human neutrophil elastase and monitored using high performance liquid chromatography and MS spectroscopic techniques. The aforementioned techniques (HPLC and MS) were also used to assess the stability of the peptide in water and human plasma. The biological activity was analyzed on human skin cells using a colorimetric XTT test, collagen synthesis evaluation, and a migration assay. The biocompatibility was analyzed with LDH cytotoxicity assay and flow cytometric analysis of activation of immune cells. Finally, RADA-PDGF2 activity in wound healing was checked in a mouse dorsal skin injury model. Results: The analysis showed that RADA-PDGF2 can self-assemble, form a hydrogel, and release a bioactive sequence when incubated with human elastase. It shows pro-proliferative and pro-migratory properties and accelerates wound closure in the mouse model compared to RADA16-I. In addition, it is not cytotoxic to human cells and does not show immunogenicity. RADA-PDGF2 seems to be a promising drug candidate for wound management.

  • Development and validation of an eco-compatible UV–Vis spectrophotometric method for the determination of Cu2+ in aqueous matrices
    • Prisco Prete
    • Davide Iannaccone
    • Antonio Proto
    • Marek Tobiszewski
    • Raffaele Cucciniello
    2023 Pełny tekst ANALYTICAL AND BIOANALYTICAL CHEMISTRY

    Cu 2+ are ubiquitous ions in the ecosystem and are responsible of serious environmental pollution. Indeed, the development of sensitive methods for Cu 2+ detection is an urgent demand. In this work, we proposed a new spectrophotometric method for Cu 2+ determination in different water matrices (distilled water, drinking water, wastewater, and river water). The method employs a bio-based organic ligand namely tetrasodium iminodisuccinate (IDS) able to form a stable complex with the analyte with a maximum absorption at 710 nm. Within the linear range of 6.3–381 mg L −1 , the limit of detection (LOD) was deter- mined to be as 1.43 mg L −1 . Moreover, the recovery data of the spiked analysis of drinking/river/wastewater water samples were also satisfactory and verified the feasibility of the method for the analysis of Cu 2+ in natural conditions. Finally, the AGREE assessment tool was used for a quantitative evaluation of the proposed method and reference method, in agreement with the green analytical chemistry principles. The results showed the lower environmental impact of the proposed method and the suitability of this novel approach for Cu 2+ in water matrices.

  • Development and validation of lumbar spine finite element model
    • Tomasz Wiczenbach
    • Łukasz Pachocki
    • Karol Daszkiewicz
    • Piotr Łuczkiewicz
    • Wojciech Witkowski
    2023 Pełny tekst PeerJ

    The functional biomechanics of the lumbar spine have been better understood by finite element method (FEM) simulations. However, there are still areas where the behavior of soft tissues can be better modeled or described in a different way. The purpose of this research is to develop and validate a lumbar spine section intended for biomechanical research. A FE model of the 50th percentile adult male (AM) Total Human Model for Safety (THUMS) v6.1 was used to implement the modifications. The main modifications were to apply orthotropic material properties and nonlinear stress-strain behavior for ligaments, hyperelastic material properties for annulus fibrosus and nucleus pulposus, and the specific content of collagenous fibers in the annulus fibrosus ground substance. Additionally, a separation of the nucleus pulposus from surrounding bones and tissues was implemented. The FE model was subjected to different loading modes, in which intervertebral rotations and disc pressures were calculated. Loading modes contained different forces and moments acting on the lumbar section: axial forces (compression and tension), shear forces, pure moments, and combined loading modes of axial forces and pure moments. The obtained ranges of motion from the modified numerical model agreed with experimental data for all loading modes. Moreover, intradiscal pressure validation for the modified model presented a good agreement with the data available from the literature. This study demonstrated the modifications of the THUMS v6.1 model and validated the obtained numerical results with existing literature in the sub-injurious range. By applying the proposed changes, it is possible to better model the behavior of the human lumbar section under various loads and moments.

  • Development of a new generation of unmanned surface and underwater vehicles using the advanced technologies and achievements towards the application of control systems by the artificial intelligence AI.
    • Mirosław Gerigk
    • Mateusz Gerigk
    2023 Per mare ad astra

    The operation of offshore structures at sea requires implementation of the advanced systems of permanent monitoring of work of such the installations. Novel solutions concerning such the systems should be associated with application of unmanned maritime surface and underwater platforms. The unmanned maritime platforms are and will be based on application of the newest achievements of some important technologies. Between these technologies is an important role to be played by the AI artificial technology used by the advanced control systems. The implementations of the advanced systems of permanent monitoring of work of offshore installations using the AI-based systems may provide an increase of the level of functionality, performance and safety of such the structures and systems. This paper presents a general approach to further development of the AUV Autonomous Underwater Vehicle and USV-WIG Unmanned Surface - Wing in Ground Vehicles equipped with a control system based on the AI technology. It is shown within the paper that it is relatively easy to develop an idea of implementation of the AUV and USV-WIG unmanned maritime vehicles but in the same time it is difficult task indeed to reach a level of real applications. The paper presents a general approach to the AUV and USV-WIG vehicle designs. A complexity of an approach to a vehicle design is shown by using the performance-oriented risk-based method. The main design drives are presented too. A brief description concerning a control system for both the AUV and USV-WIG vehicles based on the mini-brain AI control system is described. Some results of research in this area are presented. In final part of the paper the practical remarks and conclusions are given.

  • Development of a new green analytical methodology for the determination of phthalates in single-use babies diapers using ultrasound-assisted extraction and polypropylene porous membrane
    • Anna Rożańska
    • Opas Bunkoed
    • Justyna Płotka-Wasylka
    2023 MICROCHEMICAL JOURNAL

    A green extraction strategy was developed and utilized for the extraction and determination of phthalates. The extraction is based on ultrasound-assisted extraction and a polypropylene porous membrane. The Box-Behnken model was performed to optimize the extraction condition. The optimal extraction conditions are 5.5 mL of ethyl acetate, 10 min of extraction time and 55 C for extraction temperature. The developed green extraction method was successfully applied to extract target phthalate from baby's diapers. Under the optimal condition, the developed method provided acceptable recoveries in the range of 87 to 102% with a relative standard deviation lower than 13%. The developed method exhibited good linearity in the range of 0.05 to 10.0 µg g-1 with a coefficient of determination greater than 0.992 (R2). Applied the developed method coupled with the gas chromatography-mas spectroscopy (GC-MS) method, benzyl butyl phthalate (BBP) and dioctyl phthalate (DOP) were found in some diaper samples. While low concentrations of diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP) were detected in almost all diaper samples. The greenness of the developed method was also evaluated. The developed method can be used as an alternative simple, green and efficient strategy for the determination of phthalates in baby diapers. In sum, the presented article is the first step in raising awareness about carcinogenic impurities to which infants and older children are exposed.

  • Development of a simulation model of the activities of a transport and forwarding enterprise in the organization of international road cargo transportation
    • Ievgenii Lebid
    • Nataliia Luzhanska
    • Iryna Lebid
    • Alexander Mazurenko
    • Maksym Roi
    • Ievgen Medvediev
    • Tetiana Sotnikova
    • Serhii Hrevtsov
    2023 Pełny tekst Eastern-European Journal of Enterprise Technologies [ Восточно-Европейский журнал передовых технологий ]

    The object of this study is the process of planning the work of a transport and forwarding company when serving different categories of customers who need organizational support for the delivery of goods by road transport in international traffic. The solved problem is due to the need to devise recommendations for organizing the work of forwarders when interacting with customers of transport and forwarding services that export or import different categories of cargo. A simulation model of the transport and forwarding company’s work in customer service was developed and implemented in the GPSS World simulation automation package. The model provides for the optimization of organizational and management processes in cooperation with customers of transport and forwarding services. When developing the model, the duration of the types of work in which freight forwarders are involved in the export and import of goods by road transport was taken into account. The model also predicts the probability of errors in the forwarder’s work and the duration of their elimination. The application of the developed model in practice will enable the owners of transport and forwarding companies to plan the full-time number of forwarders and the duration of service provision under different conditions of interaction with customers. The simulation results reflect the performance indicators of the enterprise in serving different categories of customers. This will make it possible to optimize the work of the enterprise by planning personnel support. At the same time, the duration of transport and forwarding services will be reduced by 10–15 %, the capacity of the enterprise will increase by 6–11 %, and the reliability of service provision will increase by 8–14 %

  • Development of a spray-ejector condenser for the use in a negative CO2 emission gas power plant
    • Paweł Madejski
    • Krzysztof Banasiak
    • Paweł Ziółkowski
    • Dariusz Mikielewicz
    • Jarosław Mikielewicz
    • Tomasz Kuś
    • Michał Karch
    • Piotr Michalak
    • Milad Amiri
    • Paweł Dąbrowski
    • Kamil Stasiak
    • Navaneethan Subramanian
    • Tomasz Ochrymiuk
    2023 Pełny tekst ENERGY

    One promising solution for developing low-emission power technologies is using gaseous fuel combustion in pure oxygen when the exhaust gas mixture is composed of H2O and CO2, and where CO2 is separated after steam condensation. The paper presents the results of computational analyses providing to the Spray-Ejector Condenser (SEC) development, which is one of the crucial components of the negative CO2 gas power plant (nCO2PP) cycle development. The proposed design of the ejector-condenser to ensure the high effectivity of vapor condensation and CO2 compression with preparation to separation, ready for application in gas power cycle, is a novelty of this research. Different computational techniques leading to the development and better understating of ejector operation were applied. The main operating conditions in the characteristic connected with the developed nCO2pp cycle points were investigated to evaluate the impact of the operating conditions on SEC performances. The amount of motive water needed for the cooling purpose is susceptible to the inlet water pressure and temperature and strongly affects the generated pressure of the suction stream. The preliminary results confirm that the SEC's basic design and geometrical dimensions can be applied in the negative CO2 power plant cycle. Results from CFD modeling give the possibility to investigate the turbulent flow of water/steam/CO2 mixture together with the condensation process occurring at this same time. It is found that the average droplet diameter and motive water supplying method significantly effects the condensation intensity. The further direction of the presented computational research activities and results is to test various designs of Spray-Ejector Condensers that will enable the evaluation of the direct contact condensation process and develop the final geometrical design.

  • Development of iron doped strontium titanates as oxygen electrode for solid oxide fuel cells
    • Aleksander Mroziński
    2023 Pełny tekst

    Producing efficient solid oxide fuel cells (SOFC) without the use of harmful elements is one of the current challenges. Increasing the safety of people and reducing production costs is possible, among others, thanks to the use of iron doped strontium titanates as porous oxygen electrodes. In this thesis, the results of research on iron doped strontium titanates as potential oxygen electrodes for SOFC are presented. The research focused on: 1. Solid state reaction synthesis of iron doped strontium titanates with different amounts of substituted iron (SrTi1-xFexO3-δ, STFx) and materials with different nonstoichiometry in the strontium sublattice (SrxTi0.3Fe0.7O3-δ, STF-x). Electrical and microstructural studies have proven that these materials can be an alternative to those currently used not only at 800 °C but also at 700 °C. 2. Determining the electrochemical processes occurring in the STFx and STF-x materials during the oxygen reduction reaction and distinguishing which process limits the yield depending on the material used. Thanks to electrochemical impedance spectroscopy, a distribution of relaxation times analysis and microstructural studies, it was possible to identify the electrochemical processes occurring in these porous cathodes and indicate which ones limit the efficiency of the electrodes depending on the stoichiometry.

  • Development of novel optoelectronic sensory structures utilising colour centres in nanodiamonds and their interactions with analytes
    • Maciej Głowacki
    2023

    The goal of this dissertation was to develop and assess surface modifications of fluorescent nanodiamonds (NDs) for optical sensing. Three modification routes were tested, each aimed at a different application. Modification with poly-L-lysine (pLys) was verified for optical sensing of pH via an interrelationship between electrically negative (NV¯) and neutral (NV0) nitrogen-vacancy centres. Immobilisation of Ochratoxin A (OTA), one of the most common mycotoxins, was examined for optical investigation of interactions between the toxin and DNA in various comestible liquids. Attachment of hyperbranched polyglycerol (HPG) was tested for creation of a biomarker characterised by excellent colloidal stability in a broad pH range, in highly ionic environments and physiological media while maintaining a stable optical response. Moreover, the aim of the dissertation was to exploit techniques for depositing fluorescent NDs on glass structures to create composite platforms suitable for integration with modern optoelectronic systems used in magnetic field sensing. Matrix-assisted pulsed laser evaporation (MAPLE) was tested to obtain patterns of the diamond particles on glass coverslips for 3D sensing of the magnetic fields. Dip coating was examined to cover glass rods with the fluorescent diamond particles for drawing a composite fibre with the particles in its core. A microfluidic system was assembled to infuse anti-resonant hollow-core fibres (ARHCFs) with suspensions of fluorescent diamond particles to create platforms for optical sensing of magnetic field gradients.

  • Development of the Polish energy sector through transformation and harmonization with the European energy and climate policy
    • Waldemar Kamrat
    2023 Gaz, Woda i Technika Sanitarna

    The paper presents the dilemmas of energy sector development vs European energy policy due to the way of energy transition. The identification of barriers and opportunities for the development of the power industry is presented. The possibilities of using modern energy technologies for the processes of energy transformation are described. The path useful to achieving climate and energy goals is determined. The new method of electricity demand forecasting taking into account the demographic situation, which allows for precise determination of demand is presented. Energy policy determinants in Poland are defined. The Polish energy sector possibilities of energy transition are described.

  • Development of the System Assurance Reference Model for Generating Modular Assurance Cases
    • Andrzej Wardziński
    • Aleksander Jarzębowicz
    2023

    Assurance cases are structured arguments used to demonstrate specific system properties such as safety or security. They are used in many industrial sectors including automotive, aviation and medical devices. Larger assurance cases are usually divided into modules to manage the complexity and distribute the work. Each of the modules is developed to address specific goals allocated to the specific objects i.e. components of the system’s architecture. Such goals are applicable for given conditions of use, for instance, operational modes or target environments. It is recommended that the complete context of each of the argument modules, encompassing information about systems/components, goals and conditions of use, is described explicitly to enable efficient management and proper use of each module. This becomes even more important for component-based design, including the use of out-of-context components. In this paper, we describe a concept of a generic System Assurance Reference Model (SARM), which bridges the gap between assurance cases and the related context models. We identify the key factors that condition the high-level assurance case structure, explain how they can drive its decomposition into assurance case modules and outline the process of creating and using context models. We present a prototype solution which implements the SARM model and enables automatic data flow between models and assurance cases.

  • DevEmo—Software Developers’ Facial Expression Dataset
    • Michalina Manikowska
    • Damian Sadowski
    • Adam Sowiński
    • Michał Wróbel
    2023 Pełny tekst Applied Sciences-Basel

    The COVID-19 pandemic has increased the relevance of remote activities and digital tools for education, work, and other aspects of daily life. This reality has highlighted the need for emotion recognition technology to better understand the emotions of computer users and provide support in remote environments. Emotion recognition can play a critical role in improving the remote experience and ensuring that individuals are able to effectively engage in computer-based tasks remotely. This paper presents a new dataset, DevEmo, that can be used to train deep learning models for the purpose of emotion recognition of computer users. The dataset consists of 217 video clips of 33 students solving programming tasks. The recordings were collected in the participants’ actual work environment, capturing the students’ facial expressions as they engaged in programming tasks. The DevEmo dataset is labeled to indicate the presence of the four emotions (anger, confusion, happiness, and surprise) and a neutral state. The dataset provides a unique opportunity to explore the relationship between emotions and computer-related activities, and has the potential to support the development of more personalized and effective tools for computer-based learning environments.

  • Diagnostic Analysis of Exhaust Gas with A Quick-Changing Temperature from a Marine Diesel Engine Part II / Two Factor Analysis
    • Patrycja Puzdrowska
    2023 Pełny tekst Polish Maritime Research

    The article presents a continuation of research carried out to determine the effect of input parameters (changes in engine structure parameters) on selected output parameters (diagnostic measures), based on quickly changing exhaust gas temperature. A method of determining the simultaneous influence of two input factors (the structure parameter and the engine load) on one output factor was presented, as well as an evaluation of which of the analysed input factors has a stronger influence on the output parameter. The article presents the stages of the experimental research conducted and statistical inference based on the results. Three changing parameters for the structure were reviewed: the active cross sectional area of the inlet air channel, the injector opening pressure and the compression ratio. Based on the quickly changing temperatures of the exhaust gases, three diagnostic measures were defined and subjected to statistical tests. The following data were averaged over one cycle for a 4-stroke engine operation: the intensity of changes, the specific enthalpy and the peak-to-peak value of the exhaust gas temperature. The results of the two-factor analysis are presented. Conclusions on the analysis are given and a criterion for the selection of a diagnostic measure, depending on the analysed parameter of the structural design of the diesel engine, is proposed. The previous part of the article presented the results of the first stage of the elimination study: the one-factor statistical analysis (randomised complete plan). This paper presents the results of the second stage of the studies: two-factor analysis (block randomised plan), where the significance of the effect of changing the values of the structural parameters on the diagnostic measures were analysed in the background of a variable engine load. The next (third) part will present the results of the calculations and analysis of the interaction coefficient of significance.

  • Diagnostyka cienkościennych żelbetowych sklepień kolebkowych w budynku zabytkowym. Część II
    • Tomasz Majewski
    • Maciej Niedostatkiewicz
    2023 Pełny tekst Przegląd Budowlany

    W artykule przedstawiono opis oraz wyniki oceny stanu technicznego konstrukcji przekrycia Hali Głównej Dworca Kolejowego Gdańsk Główny. Ze względu na prowadzone prace związane z remontem kapitalnym Dworca Głównego PKP w Gdań- sku zaistniała konieczność przeprowadzenia rewitalizacji poddasza Hali Głównej, obejmująca między innymi jego termomodernizację (ocieplenie wysklepek) oraz zabezpieczenie elementów wiązarów dachowych przed pożarem. W celu oceny stanu technicznego skle- pień oraz poziomu wytężenia elementów konstrukcyjnych dachu wykonano szereg badań i pomiarów, w tym skanowanie zbroje- nia żelbetowych sklepień kolebkowych z zastosowaniem detekto- ra ferromagnetycznego w celu oceny średnicy, rozstawu i grubo- ści otulenia prętów zbrojenia łupin oraz badania ultradźwiękowe betonu przy użyciu betonoskopu w celu oszacowania wytrzyma- łości betonu na ściskanie, jego jednorodności oraz grubości płasz- cza powłoki. W artykule przedstawiono wyniki wykonanych badań i analiz, które pozwoliły na zaproponowanie sposobu naprawy cien- kościennych sklepień żelbetowych typu Rabitza.

  • Diagnostyka i naprawy dylatacji konstrukcyjnych w płytach posadzkowych. Część II
    • Sylwia Świątek-Żołyńska
    • Maciej Niedostatkiewicz
    • Sebastian Kasprzak
    2023 Pełny tekst Przegląd Budowlany

    W artykule przedstawiono najczęściej spotykane uszkodzenia dylatacji konstrukcyjnych w płytach posadzkowych na gruncie wraz z omówieniem sposobów naprawy. Dylatacje konstrukcyjne w płytach posadzkowych najczęściej realizowane są z wykorzystaniem dylatacji systemowych, które w trakcie dłu- goletniej eksploatacji ulegają naturalnemu zużyciu lub uszkodze- niom mechanicznym. W artykule omówiono istotne aspekty tech- nologiczno-materiałowe w zakresie demontażu starych i montażu nowych systemowych dylatacji konstrukcyjnych z uwzględnie- niem funkcji obiektu. Przedstawiono również przypadki połącze- nia starych płyt posadzkowych z nowo wykonywanymi, a także rozwiązania w zakresie remontów i napraw dylatacji w bramach przejazdowych oraz szczelin skurczowych.

  • Diagnostyka, naprawy i wzmacnianie elementów żelbetowych uszkodoznych w następstwie skurczu
    • Maciej Niedostatkiewicz
    • Tomasz Majewski
    2023 Pełny tekst

    W artykule opsano wpływ zjawisk reologicznych: skurczu i pełzania na wytężenie i zarysowanie żelbetowych elementów konstrukcyjnych

  • Diagnostyka ogniw paliwowych
    • Łukasz Gaweł
    2023 Chemia Przemysłowa

    Rosnące zapotrzebowanie na zieloną energię elektryczną, ograniczenia związane z normami emisji spalin, większa świadomość ekologiczna społeczeństwa, czy rozwój dolin wodorowych determinują fakt, że ogniwa paliwowe typu PEM będą stanowić ważne źródło energii elektrycznej w niedalekiej przyszłości.

  • Dielectric Spectroscopy Studies and Modelling of Piezoelectric Properties of Multiferroic Ceramics
    • Agata Lisińska-Czekaj
    • Dionizy Czekaj
    • Barbara Garbarz-Glos
    • Wojciech Bąk
    • Temesgen Tadeyos Zate
    • Jae-Ho Jeon
    2023 Pełny tekst Applied Sciences-Basel

    Compounds and solid solutions of bismuth ferrite (BiFeO3)—barium titanate (BaTiO3) system are of great scientific and engineering interest as multiferroic and potential high-temperature lead-free piezoelectric materials. In the present paper, the results of research on the synthesis and characterisation of 0.67Bi1.02FeO3–0.33BaTiO3 (67BFBT) ceramics in terms of crystal structure and dielectric and piezoelectric properties are reported. It was found that the produced 67BFBT ceramics were characterised by a tetragonal crystal structure described by the P4mm space group, an average crystallite size <D> 80 nm, and an average strain <#> = 0.01%. Broad-band dielectric spectroscopy (BBDS) was employed to characterise the dielectric response of polycrystalline ceramics. The frequency range from n = 101 Hz to n = 105 Hz was used to characterise the influence of the electric field strength on dielectric response of the ceramic sample at room temperature. The dielectric spectra were checked for consistency with the Kramers–Kronig test, and the high quality of the measurements were confirmed. The electric equivalent circuit method was used to fit the dielectric spectra within the frequency range that corresponded to the occurrence of the resonant spectra of the radial mode for thin disk sample, i.e., from n = 105 Hz to n = 107 Hz and the temperature range from T = 20 C to T = 50 C. The electric equivalent circuit [RsCPE1([L1R1C1]C0)] was used, and good fitting quality was reached. The relevant calculations were performed, and it was found that the piezoelectric charge coefficient exhibited a value of d31 = 35 pC/N and the planar coupling factor was kp = 31% at room temperature. Analysis of impedance spectra performed in terms of circumferential magnetic field made it possible to establish an influence of magnetic field on piezoelectric parameters of 67BFBT multiferroic ceramics. Additionally, the “magnetic” tunability of the modulus of the complex dielectric permittivity makes 67BFBT a sensing material with vast potential.

  • Differentiating patients with obstructive sleep apnea from healthy controls based on heart rate-blood pressure coupling quantified by entropy-based indices
    • Paweł Pilarczyk
    • Grzegorz Graff
    • Jose Amigo
    • Katarzyna Tessmer
    • Krzysztof Narkiewicz
    • Krzysztof Narkiewicz
    • Beata Graff
    2023 Pełny tekst CHAOS

    We introduce an entropy-based classification method for pairs of sequences (ECPS) for quantifying mutual dependencies in heart rate and beat-to-beat blood pressure recordings. The purpose of the method is to build a classifier for data in which each item consists of two intertwined data series taken for each subject. The method is based on ordinal patterns and uses entropy-like indices. Machine learning is used to select a subset of indices most suitable for our classification problem in order to build an optimal yet simple model for distinguishing between patients suffering from obstructive sleep apnea and a control group.

  • Digestate Quality Originating from Kitchen Waste
    • Joanna Mioduska
    • Aleksandra Grabowiec
    • Jan Hupka
    2023 Pełny tekst Applied Sciences-Basel

    This paper examines the influence of biomass directed to anaerobic digestion on the quality of digestate, specifically focusing on the presence of undesirable substances, such as plastics, including biodegradable ones. It analyses the susceptibility of selected bioplastics to degradation and addresses the problem of reliable identification of microplastics in both feedstock—directed to anaerobic digestion—and produced digestate. The review indicates the advantages of using kitchen waste as a feedstock for anaerobic digestion. The constant availability of kitchen waste as a raw material, its homogeneous composition, and the fact that it is not subjected to seasonal fluctuations, facilitates its management in the anaerobic digestion process. However, to ensure the desired quality of a digestate, it is important to carry the selective collection of waste at the source. The review refers to the issues of quality, materials, and regulations, and it may be useful for readers entering the subject of a material loop, as well as those already involved in the subject, including local government units. Anaerobic digestion of kitchen waste is an important part of a renewable economy, providing year-round constantly available substrate for energy production that is not seasonally dependent.

  • Digital data and tools in transformative education to preserve architecture and cultural heritage: case studies from Italy and Poland
    • Justyna Borucka
    • Sandro Parrinello
    • Francesca Picchio
    2023 Pełny tekst Global Journal of Engineering Education

    In this article, the authors present the findings and results of a recent study focused on various collaborative activities mostly between Italy and Poland, and digital teaching platforms aimed at educating future architects. These architects are envisioned as curators of digital data and experts in using digital tools in the field of architecture and architectural heritage. The investigation had two main objectives. Firstly, it aimed to develop an educational programme that serves the aforementioned purpose, and secondly, to facilitate educational experiments by integrating education and research in the realm of digital architecture, specifically in support of architectural and urban heritage. All teaching experiments conducted in this study were closely related to the ongoing European Union (EU) research and didactic projects: H2020 PROMETHEUS and EMDMVREA. The authors propose that a European approach to digital transformation for cultural heritage sustainability should emphasise the consolidation of knowledge for young students, enabling them to interact and collaborate with the creative industries and virtual products. This can be achieved by familiarising students with the languages and practices of digitisation and content enrichment.

  • Digital Transformation and Its Influence on Sustainable Manufacturing and Business Practices
    • Issam A. R. Moghrabi
    • Sameer Ahmad Bhat
    • Piotr Szczuko
    • Rawan A. AlKhaled
    • Muneer Ahmad Dar
    2023 Pełny tekst Sustainability

    The paper focuses on the relationship between businesses and digital transformation, and how digital transformation has changed manufacturing in several ways. Aspects like Cloud Computing, vertical and horizontal integration, data communication, and the internet have contributed to sustainable manufacturing by decentralizing supply chains. In addition, digital transformation inventions such as predictive analysis and big data analytics have helped optimize sustainable manufacturing by reducing overproduction or underproduction through predicting customer demands. It integrates digital technology to enhance business operations, consumer engagement, supply chains, and coordination, the manufacturing process, energy conservation, efficiency, and environmental conservation and culture to satisfy business needs. Businesses’ failure to embrace digital transformation in this era contributes to their demise. This research paper will analyze and contrast several businesses and the extent of digital transformation’s influence on them during COVID-19. A twostage study is conducted, the first stage assesses a chosen exemplary business success over three years. The second stage investigates the reasons for success, or otherwise, and the connection to digitalization in the business. Our outcomes suggest that digital transformation strongly influences firms’ effectiveness and survival from a technology-centric and business model standpoint. Some essential generic recommendations are suggested based on the results obtained.

  • Digitalization and digital skills development patterns. Evidence for European countries
    • Ewa Lechman
    • Helena Anacka
    2023

    This chapter contextualizes the digitalization process and the digital skills concept. It discusses the very process of technology diffusion, emphasizing several unique features of digital technologies that make them globally available. Next, it turns to the digital skills concept, clarifying how and why they reshape the societal and economic landscape. It also briefly addresses the digital divide and skill-biased technological change. The provided conceptual considerations are supported by numerical evidence regarding digital technologies and digital skills in Europe in the time span between 1980 and 2021. Using the logistic growth model, it draws digital diffusion trajectories for selected ICT indicators; it also examines the cross-country digital inequalities considering not only access to and use of ICT but also in terms of digital skills.

  • Digitalization of Building Site Management in the Construction Industry
    • Çağatay Takva
    • Jan Cudzik
    • Zeynep İlerisoy
    2023 Pełny tekst International Journal of Sustainable Construction Engineering and Technology

    With Industry 4.0, a digital transformation has started in the construction industry. However, 4.0 technologies have difficulties in the integration of digital systems due to the diversity and complexity of the processes in the construction industry. Multidisciplinary work in architectural projects and the need for high productivity require digital renovation planning in the construction industry. The application of the technologies that emerged because of digital transformation on the building site has revealed the concept of the smart building site. Within the framework of many current issues such as the smart building site, the digital transformation on the building sites needs to be explored and defined. In this study, a bibliometric analysis was carried out on the publications in this field by evaluating the transformation potentials of the digitalized building sites of the future. Academic publications that will raise awareness in the improvement of building site management and the development of digital systems have been determined. Conceptual integrity was created by seeing the research gap for digitalization in building site management and it was aimed to guide researchers in future studies. As a result, based on the research area analysis and the diversity of academic publications, it was seen that the studies in the field of architecture were insufficient compared to the engineering fields.

  • Diiodo-BODIPY Sensitizing of the [Mo3S13]2– Cluster for Noble-Metal-Free Visible-Light-Driven Hydrogen Evolution within a Polyampholytic Matrix
    • Daniel Costabel
    • Afshin Nabiyan
    • Avinash Chettri
    • Franz Jacobi
    • Magdalena Heiland
    • Julien Guthmuller
    • Stephan Kupfer
    • Maria WäCHTLER
    • Benjamin Dietzek-Ivanšić
    • Carsten Streb
    • Felix H. Schacher
    • Kalina Peneva
    2023 Pełny tekst ACS Applied Materials & Interfaces

    We report on a photocatalytic setup that utilizes the organic photosensitizer (PS) diiodo-BODIPY and the non-precious-metal-based hydrogen evolution reaction (HER) catalyst (NH4)2[Mo3S13] together with a polyampholytic unimolecular matrix poly(dehydroalanine)-graft-poly(ethyleneglycol) (PDha-g-PEG) in aqueous media. The system shows exceptionally high performance with turnover numbers (TON > 7300) and turnover frequencies (TOF > 450 h−1) that are typical for noble-metal- containing systems. Excited state absorption spectra reveal the formation of a long-lived triplet state of the PS in both aqueous and organic media. The system is a blueprint for developing noble-metal-free HER in water. Component optimization, e.g., by modification of the meso substituent of the PS and the composition of the HER catalyst, is further possible.

  • Dimensionality-Reduced Antenna Modeling with Stochastically Established Constrained Domain
    • Anna Pietrenko-Dąbrowska
    • Sławomir Kozieł
    2023 KNOWLEDGE-BASED SYSTEMS

    Over the recent years, surrogate modeling methods have become increasingly widespread in the design of contemporary antenna systems. On the one hand, it is associated with a growing awareness of numerical optimization, instrumental in achieving high-performance structures. On the other hand, considerable computational expenses incurred by massive full-wave electromagnetic (EM) analyses, routinely employed as a major design tool, foster the development of novel design techniques that exhibit practically acceptable costs while ensuring reliability. In this context, substituting EM simulations by fast surrogates is a profitable solution. Data-driven modeling is arguably the most popular approach owing to its versatility and the abundance of specific methods. Yet, a construction of approximation surrogates is severely encumbered by the curse of dimensionality, and even more so by the broad ranges of material and geometry parameters the model should cover to be applicable for solving practical design tasks. The recently reported performance-driven modeling paradigm offers workaround these obstacles by restricting the surrogate rendition to a small section of the parameter space, containing designs of sufficiently high quality according to performance requirements imposed on the system under study. Nevertheless, identification of this region is based on database designs that have to be pre-optimized, which is associated with significant CPU expenses. The usage of the reference designs can be replaced by stochastic domain identification, leading to considerable computational savings. This paper introduces a further advancement, where the metamodel domain is outlined based on the spectral analysis of the random observables pre-selected using an automated decision-making process. Our procedure retains the benefits of the prior techniques but also reduces the domain dimensionality, which translates into additional cost reduction of training data acquisition. These have been conclusively demonstrated through numerical validation involving three microstrip antennas and comprehensive comparisons with six state-of-the-art benchmark techniques.

  • Direct design of Controlled Modulus Columns (CMC) based on in-situ testing
    • Kamila Mikina
    2023 Pełny tekst

    In this paper, the serviceability limit state and bearing capacity of tension screw displacement piles were analyzed using the results of static pile load tests, carried out on the test plot near the Elbląg city, and field, and laboratory tests. The paper presents the methodology of determining the pile load-settlement curve using different types of t-z transfer functions. The new method of constructing the pile load-settlement curves using the trilinear transfer curves, analogous to the functions developed by Frank and Zhao (1982) based on pressuremeter test, is proposed taking into consideration the results of flat dilatometer test. The analogy between pile shaft friction mobilization and direct shearing of the concrete-soil interface was used. The proposed method was derived from 44 shear-displacement curves of cohesionless, cohesive and organic soils in tests performed in a direct shear apparatus on rough or smooth concrete interfaces. The maximum shear stresses on interface were determined, and the slope of skin friction mobilization was expressed as a function of constrained modulus from DMT. Separate friction mobilization functions were proposed for coarse-grained soils (sands), fine-grained (cohesive), and organic soils. The proposed transfer curves takes into account the installation effects, i.e. the applied pile technology. The soil parameters and stress state before and after pile installation were evaluated using the results of CPTU and DMT soundings. The proposed method was validated using the results of eight static load pull-out tests on screw displacement piles performed on the trial test plot. The study is also focused on the determination of soil parameters before and after pile installation using the results of CPT and DMT soundings. The results of uplift static pile load tests were analyzed and the influence of pile length and the after their construction (set-up) on bearing capacity was studied. Currently used CPT-based methods (direct methods) for pile bearing capacity were discussed in this thesis. They were applied then to estimate the bearing capacities of three piles of different lengths. The results were compared with the bearing capacities obtained from the method elaborated by the author. In conclusion, the possibilities for future research to expand the proposed method were presented and its limitations were discussed.

  • Direct determination of paraquat herbicide by square-wave voltammetry by two-step transfer mechanism at heterogeneous boron-doped carbon nanowall electrodes
    • Sourav Sain
    • Mateusz Ficek
    • Adrian Olejnik
    • Mirosław Sawczak
    • Robert Bogdanowicz
    • Susanta Sinha Roy
    2023 Pełny tekst DIAMOND AND RELATED MATERIALS

    Boron-doped carbon nanowalls (B:CNW) versus boron-doped diamond (BDD) materials were investigated for the effective electrochemical detection of highly toxic herbicide paraquat (PQ). Depending on the surface morphology and functional groups of BDD and B:CNWs, the electrochemical absorption and detection of the target analyte PQ revealed different detection mechanisms. The surface absorption mechanism was mainly observed for BDD, while for B:CNWs, both surficial and edge absorption were observed due to the sharp edges of carbon nanowalls. This effectually drives the high heterogenous electron transfer kinetics at absorption sites. Detection of PQ was carried out in phosphate buffer solution with an optimized pH of 10 and parameters of the square-wave voltammetry. Comparative studies show higher voltammetric current peak heights for B:CNWs (∼90.5 μA) than BDD (∼7.5 μA) at a much lower PQ concentration of 4 μM. B:CNWs show a higher sensitivity of 11 μA/μM/cm2 than BDD of 2.23 μA/μM/cm2, hence BDD shows a LOD of 1.8 μM, whereas B:CNWs have a much lower LOD of 0.47 μM. Density functional theory calculations (DFT) show a higher propensity of the B:CNW models toward electrocatalytic reduction of the PQ. Moreover, the proposed two-step detection mechanism is strongly supported by the distribution of the PQ electrostatic potential in different oxidation states in conjunction with the slab surfaces. The higher the sensitivity, the lower the LOD, and the excellent performance of B:CNWs in the detection of PQ in real water samples also suggests its potential for use in the environmental monitoring and assessment of emerging pollutants.

  • Direct electrical brain stimulation of human memory: lessons learnt and future perspectives
    • Michał Kucewicz
    2023 Brain: A Journal of Neurology

    Modulation of cognitive functions supporting human declarative memory is one of the grand challenges of neuroscience, and of vast importance for a variety of neuropsychiatric, neurodegenerative and neurodevelopmental diseases. Despite a recent surge of successful attempts at improving performance in a range of memory tasks, the optimal approaches and parameters for memory enhancement have yet to be determined. On a more fundamental level, it remains elusive how delivering electrical current in a given brain area leads to enhanced memory processing. Starting from the local and distal physiological effects on neural populations, the mechanisms of enhanced memory encoding, maintenance, consolidation, or recall in response to direct electrical stimulation are only now being unraveled. With the advent of innovative neurotechnologies for concurrent recording and stimulation intracranially in the human brain, it becomes possible to study both acute and chronic effects of stimulation on memory performance and the underlying neural activities. In this review, we summarize the effects of various invasive stimulation approaches for modulating memory functions. We first outline the challenges that were faced in the initial studies of memory enhancement and the lessons learned. Electrophysiological biomarkers are then reviewed as more objective measures of the stimulation effects than behavioral outcomes. Finally, we classify the various stimulation approaches into continuous and phasic modulation with open or closed loop for responsive stimulation based on analysis of the recorded neural activities. Although the potential advantage of closed-loop responsive stimulation over the classic open-loop approaches is inconclusive, we foresee the emerging results from ongoing longitudinal studies and clinical trials to shed light on both the mechanisms and optimal strategies for improving declarative memory. Adaptive stimulation based on the biomarker analysis over extended periods of time is proposed as a future direction for obtaining lasting effects on memory functions. Chronic tracking and modulation of neural activities intracranially through adaptive stimulation opens tantalizing new avenues to continually monitor and treat memory and cognitive deficits in a range of brain disorders.

  • Direct injection liquid chromatography-mass spectrometry (DI-LC-MS) analysis for rapid lipidomic profiling of extracellular vesicles
    • Weronika Hewelt-Belka
    • Michał Młynarczyk
    • Jorge Matinha-Cardoso
    • Felicja Gajdowska
    • Paulo Oliveira
    • Danuta Gutowska-Owsiak
    2023

    Extracellular vesicles (EVs) are small, spherical particles produced by eukaryotic and prokaryotic cells, surrounded by a bilayer membrane and carrying various bioactive molecules, such as proteins, surface receptors, membrane and soluble proteins, lipids, and nucleic acids. EVs are of substantial interest because of their important roles in cell communication, epigenetic regulation and possible application in disease diagnosis and therapeutic strategies. Lipids are essential components of EVs since they are the building blocks of their bilayer membrane. Although the EV's lipid composition and its biological role are still unknown, this topic is gaining considerable attention in recent years. Lipidomics is a useful tool for characterisation of EVs' lipid profiles. However, such analysis can be challenging due to the limited size of sample (especially for EV obtained from primary cells), low lipid concentration and detection limits. Usually, extraction is performed before MS analysis to isolate lipids and remove interfering compounds such as proteins. In this work, we have tested the approach of direct injection LC-MS (DI-LC-MS) analysis of EV to characterize the lipidome without lipid extraction. RP-LC-Q-TOF-MS was used for the lipidomic profiling. EVs from various origins isolated by ultracentrifugation have been tested: from bovine and human sera, and EV derived from cultured eukaryotic and bacteria cells (incl. exosome-enriched small EVs, microvesicles and apoptotic bodies). We have evaluated the lipidome coverage and repeatability of the DI approach and compared it with the conventional extraction techniques used for the EVs' lipidomics. The results showed that injection of intact EVs allows the lipid analysis without a priori extraction, where high content of organic solvents in the mobile phase enables EV disintegration and lipid separation on the chromatographic column. The lipidome coverage obtained from conventional extraction and direct injection was comparable. However, the chemical background was reduced in DI approach in comparison to lipid extraction. The DI approach requires small injection volume (e.g. 0.1 µL depending on the EV particle number) and does not require an evaporation step. DI approach simplifies the procedure and makes EV lipidomic analysis fast and convenient without loss of lipidome coverage or repeatability.

  • Discovering relationships between data in an enterprise information system using log analysis
    • Łukasz Korzeniowski
    • Krzysztof Goczyła
    2023 Pełny tekst

    Enterprise systems are inherently complex and maintaining their full, up-to-date overview poses a serious challenge to the enterprise architects’ teams. This problem encourages the search for automated means of discovering knowledge about such systems. An important aspect of this knowledge is understanding the data that are processed by applications and their relationships. In our previous work, we used application logs of an enterprise system to derive knowledge about the interactions taking place between applications. In this paper, we further explore logs to discover correspondence between data processed by different applications. Our contribution is the following: we propose a method for discovering relationships between data using log analysis, we validate our method against a benchmark system AcmeAir and we validate our method against a real-life system running at Nordea Bank.

  • Discrete identification of continuous non-linear and non-stationary dynamical systems that is insensitive to noise correlation and measurement outliers
    • Janusz Kozłowski
    • Zdzisław Kowalczuk
    2023 Pełny tekst Archives of Control Sciences

    The paper uses specific parameter estimation methods to identify the coefficients of continuous-time models represented by linear and non-linear ordinary differential equations. The necessary approximation of such systems in discrete time in the form of utility models is achieved by the use of properly tuned `integrating filters' of the FIR type. The resulting discrete-time descriptions retain the original continuous parameterization and can be identified, for example, by the classical least squares procedure. Since in the presence of correlated noise, the estimated parameter values are burdened with an unavoidable systematic error (manifested by asymptotic bias of the estimates), in order to significantly improve the identification consistency, the method of instrumental variables is used here. In our research we use an estimation algorithm based on the LA criterion of the least sum of absolute values, which is optimal in identifying linear and non-linear systems in the case of sporadic measurement errors. In the paper, we propose a procedure for determining the instrumental variable for a continuous model with non-linearity (related to the Wienerian system) in order to remove the evaluation bias, and a recursive sub-optimal version of the LA estmator. This algorithm is given in a simple (LA) version and in an instrumental variable version (IV-LA), which is robust to outliers, removes evaluation bias, and is suited to the task of identifying processes with non-linear dynamics (semi-Wienerian/NLID). In conclusion, the effectiveness of the proposed algorithmic solutions has been demonstrated by numerical simulations of the mechanical system, which is an essential part of the suspension system of a wheeled vehicle.

  • Discriminating macromolecular interactions based on an impedimetric fingerprint supported by multivariate data analysis for rapid and label-free Escherichia coli recognition in human urine
    • Adrian Koterwa
    • Mattia Pierpaoli
    • Bożena Nejman-Faleńczyk
    • Sylwia Bloch
    • Artur Zieliński
    • Wioletta Adamus-Białek
    • Zofia Jeleniewska
    • Bartosz Trzaskowski
    • Robert Bogdanowicz
    • Grzegorz Węgrzyn
    • Paweł Niedziałkowski
    • Jacek Ryl
    2023 Pełny tekst BIOSENSORS & BIOELECTRONICS

    This manuscript presents a novel approach to address the challenges of electrode fouling and highly complex electrode nanoarchitecture, which are primary concerns for biosensors operating in real environments. The proposed approach utilizes multiparametric impedance discriminant analysis (MIDA) to obtain a fingerprint of the macromolecular interactions on flat glassy carbon surfaces, achieved through self-organized, drop-cast, receptor-functionalized Au nanocube (AuNC) patterns. Real-time monitoring is combined with singular value decomposition and partial least squares discriminant analysis, which enables selective identification of the analyte from raw impedance data, without the use of electric equivalent circuits. As a proof-of-concept, the authors demonstrate the ability to detect Escherichia coli in real human urine using an aptamer-based biosensor that targets RNA polymerase. This is significant, as uropathogenic E. coli is a difficult-to-treat pathogen that is responsible for the majority of hospital-acquired urinary tract infection cases. The proposed approach offers a limit of detection of 11.3 CFU/mL for the uropathogenic E. coli strain No. 57, an analytical range in all studied concentrations (up to 105 CFU/mL), without the use of antifouling strategies, yet not being specific vs other E.coli strain studied (BL21(DE3)). The MIDA approach allowed to identify negative overpotentials (−0.35 to −0.10 V vs Ag/AgCl) as most suitable for the analysis, offering over 80% sensitivity and accuracy, and the measurement was carried out in just 2 min. Moreover, this approach is scalable and can be applied to other biosensor platforms.

  • Dissimilar autogenous TIG joint of Alloy 617 and AISI 304H steel for AUSC application
    • Sachin Sirohi
    • Amit Kumar
    • Shailesh M. Pandey
    • Priyambada Purohit
    • Dariusz Fydrych
    • Sanjeev Kumar
    • Chandan Pandey
    2023 Pełny tekst Heliyon

    To reduce costs and improve high-temperature performance in Advanced Ultra Super Critical (AUSC) boilers, it is necessary to weld austenitic steel to Inconel alloy. In this study, the autogenous tungsten inert gas (TIG) welding process was used to join Alloy 617 and an austenitic AISI 304H steel plate of thickness 5 mm. Microstructural analysis showed that the microstructure formation was uneven along the weldments, with columnar and cellular dendrites near the interface while the central area of the weld exhibited a combination of columnar, cellular, and equiaxed dendrites. The use of energy dispersive spectroscopy and electron probe micro-analysis unveiled the presence of an unmixed layer at the interface between the weld and AISI 304H steel. Furthermore, a notable variation in the concentration of alloying elements such as Fe, Cr, Ni, Co, and Mo was observed. Within the weld metal, inter-dendritic areas showed the presence of precipitates rich in Cr, Ti, and Mo. Meanwhile, the heat-affected zone (HAZ) of Alloy 617 exhibited the presence of phases like Cr and Mo-rich M23C6 as well as Mo-rich M6C. Hardness tests showed non-uniform hardness along the weldments, with a hardness of 199 ± 6 HV in the weld metal and 225 ± 4 HV in Alloy 617 HAZ, and 207 ± 7 HV in AISI 304H HAZ. The Mo and Cr segregation in the inter-dendritic spaces led to a decline in the tensile properties of the welded parts and resulted in failure from the region of the weld metal.

  • Dissociative Electron Attachment to 5-Iodo-4-thio-2′-deoxyuridine: A Potential Radiosensitizer of Hypoxic Cells
    • Muhammad Saqib
    • Eugene Arthur-Baidoo
    • Farhad Izadi
    • Adrian Szczyrba
    • Magdalena Datta
    • Sebastian Demkowicz
    • Janusz Rak
    • Stephan Denifl
    2023 Pełny tekst Journal of Physical Chemistry Letters

    In the search for effective radiosensitizers for tumor cells, halogenated uracils have attracted more attention due to their large cross section for dissociation upon the attachment of low-energy electrons. In this study, we investigated dissociative electron attachment (DEA) to 5-iodo-4-thio-2'-deoxyuridine, a potential radiosensitizer using a crossed electron-molecule beam experiment coupled with quadrupole mass spectrometry. The experimental results were supported by calculations on the threshold energies of formed anions and transition state calculations. We show that low-energy electrons with kinetic energies near 0 eV may effectively decompose the molecule upon DEA. The by far most abundant anion observed corresponds to the iodine anion (I-). Due to the associated bond cleavage, a radical site is formed at the C5 position, which may initiate strand break formation if the molecule is incorporated into a DNA strand. Our results reflect the conclusion from previous radiolysis studies with the title compound, suggesting its potential as a radiosensitizer.

  • Dissolution of Nb-doped hydroxyapatite prepared via low-temperature mechanochemical method: Spectroscopy studies
    • Wojciech Korzeniewski
    • Agnieszka Witkowska
    2023 NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

    Calcium phosphate glass ceramics with nominal hydroxyapatite stoichiometry doped with niobium were synthesized using simple as well as low-temperature mechanochemical method and then in the form of compressed pellet were submitted to the static dissolution process in distilled water for one month. The results of structural analysis, performed mainly on the base of spectroscopic methods such as: infrared absorption spectroscopy, energy-dispersive X-ray spectroscopy, photoelectron spectroscopy as well as soft and tender X-ray absorption spectroscopies, indicate that during the dissolution process the presence of niobium reduced the dynamics of the calcium phosphate new layer formation, without a significant impact on the morphology and stoichiometry of this layer. Moreover, the Nb addition favored the formation of hydroxyapatite and Ca-deficient hydroxyapatite, both during the synthesis and dissolution processes, and facilitated the incorporation of the CO3-2 groups into the ceramic matrix, leading to the formation of B-type carbonated apatite.

  • Distinct hippocampal-prefrontal neural assemblies coordinate memory encoding, maintenance, and recall
    • Aleksander Domanski
    • Michał Kucewicz
    • Eleonora Russo
    • Mark D. Tricklebank
    • J. Emma Robinson
    • Daniel Durstewitz
    • Matthew W. Jones
    2023 Pełny tekst CURRENT BIOLOGY

    Short-term memory enables incorporation of recent experience into subsequent decision-making. This processing recruits both the prefrontal cortex and hippocampus, where neurons encode task cues, rules, and outcomes. However, precisely which information is carried when, and by which neurons, remains unclear. Using population decoding of activity in rat medial prefrontal cortex (mPFC) and dorsal hippocampal CA1, we confirm that mPFC populations lead in maintaining sample information across delays of an operant nonmatch to sample task, despite individual neurons firing only transiently. During sample encoding, distinct mPFC subpopulations joined distributed CA1-mPFC cell assemblies hallmarked by 4–5 Hz rhythmic modulation; CA1-mPFC assemblies re-emerged during choice episodes but were not 4–5 Hz modulated. Delay-dependent errors arose when attenuated rhythmic assembly activity heralded collapse of sustained mPFC encoding. Our results map component processes of memory-guided decisions onto heterogeneous CA1-mPFC subpopulations and the dynamics of physiologically distinct, distributed cell assemblies.