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Diagnosis of Damage in a Steel Tank with Self-Supported Roof through Numerical Analysis
PublicationThe safety of civil engineering structures is one of the most important issues of building industry. That is why the assessment of the damage-involved structural response has recently become of major concern to engineers. Among a number of different approaches to diagnosis of damage, the method of measuring the changes in natural frequencies is considered to be one of the most effective indicators of global damage. From the practical...
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The role of rewards and demands in burnout among surgical nurses
PublicationObjective: Job rewards have both, an intrinsic and an extrinsic motivational potential, and lead to employees’ development as well as help them to achieve work goals. Rewards can balance job demands and protect from burnout. Due to changes on the labour market, new studies are needed. The aim of our study was to examine the role of demands and individual rewards (and their absence) in burnout among surgical nurses. Materials and...
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Physical and mathematical modelling of implant-fascia system in order to improve laparoscopic repair of ventral hernia
PublicationThis paper describes an investigation of biomechanical behaviour of hernia repair, which is focused on the selection of safe linking of certain type of implant with fascia in laparoscopic operation. The strength of various fixations of the implant to the fascia is analysed. Methods: The research is based on experimental observations of operated hernia model behaviour during a dynamic impulse load corresponding to post-operative...
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Deep CNN based decision support system for detection and assessing the stage of diabetic retinopathy
PublicationThe diabetic retinopathy is a disease caused by long-standing diabetes. Lack of effective treatment can lead to vision impairment and even irreversible blindness. The disease can be diagnosed by examining digital color fundus photographs of retina. In this paper we propose deep learning approach to automated diabetic retinopathy screening. Deep convolutional neural networks (CNN) - the most popular kind of deep learning algorithms...
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Temperature influence on tyre/road noise on poroelastic road surface based on laboratory measurements
PublicationThe temperature effect on measured tyre/road noise is very important phenomena as it may lead to significant errors in measurement results due to substantial influence of this parameter on the obtained values. It depends mainly on the particular tyre-road combination. It is different for dense and porous as well as for bituminous and cement concrete pavements. It differs also depending on tested tyre. The correction procedure for...
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Red Kale (Brassica oleracea L. ssp. acephala L. var. sabellica) Induces Apoptosis in Human Colorectal Cancer Cells In Vitro
PublicationThis article presents the results of studies investigating the effect of red kale (Brassica oleracea L. ssp. acephala L. var. sabellica) extract on cancer cells (HT-29). The cytotoxicity of the red kale extract was assessed using MTT and LDH assays, while qRT-PCR was employed to analyze the expression of genes associated with the p53 signaling pathway to elucidate the effect of the extract on cancer cells. Furthermore, HPLC-ESI-QTOF-MS/MS...
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Positive management of the university
PublicationPurpose: To demonstrate that contemporary universities may be improved by synthesis of strategic antinomies, i.e. seeking the possibility of combining opposite approaches to solving problems concerning university organization and management. Findings: That approach discounts the importance of building positive relationships between members of staff and undertaking activities intended to create a situation where the...
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Mechanical behaviour of knit synthetic mesh used in hernia surgery
PublicationPurpose: There is a discussion in literature concerning mechanical properties and modelling of surgical meshes. An important feature of elastic modulus dependency on load history is taken into account in this paper, as implants are subjected to variable loading during human activity. The example of DynaMesh®-IPOM surgical implant is studied. Methods: The analysis is based on failure tension tests and cyclic loading and unloading...
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Planning the City Against Barriers. Enhancing the Role of Public Spaces
PublicationContemporary cities are being fragmented by growing number of technical barriers like roads, railways, infrastructural objects, that generate variety of problems of different nature. The aim of the research is to present the issues connected with such barriers in the city and the ways of solving them. Main problems are e.g.: the destruction of the complexity of urban fabric, functional disadvantages, environmental and landscape...
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Linking of adjacent three-storey buildings for mitigation of structural pounding during earthquakes
PublicationThe reports after major earthquakes indicate that the earthquake-induced pounding between insufficiently separated buildings may lead to significant damage or even total collapse of structures. An intensive study has recently been carried out on mitigation of pounding hazards so as to minimize the structural damages or prevent collisions at all. The aim of this paper is to investigate the effectiveness of the method when two adjacent...
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The impact of bankruptcy regimes on entrepreneurship and innovation. Is there any relationship?
PublicationThe literature review indicates that bankruptcy law may play an important role in and be one of the factors infuencing the development of entrepreneurship, innovation, and thus economic growth, among other things. In previous studies, the analysis of the impact of bankruptcy law on individual variables has been conducted independently. Our aim was to conduct a holistic analysis, taking several factors into account simultaneously....
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Application of the ISE Optimized Proportional Control of the Wave Maker in a Towing Tank
PublicationThis paper presents the improvement of the wave maker control system. The wave maker is a facility widely used in hydromechanics laboratories to generate waves in towing tanks. It is equipped with an electrohydraulic drive and an actuator submerged into water. The waves are generated to model the environmental conditions for physical experiments, performed on reduced-scale models of maritime objects. The physical experiments allow...
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Tolerance Optimization of Antenna Structures by Means of Response Feature Surrogates
PublicationFabrication tolerances and other types of uncertainties, e.g., the lack of precise knowledge of material parameters, have detrimental effects on electrical and field performance of antenna systems. In the case of input characteristics these are particularly noticeable for narrow- and multi-band antennas where deviations of geometry parameters from their nominal values lead to frequency shifts of the operating frequency bands. Improving...
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Development and Assessment of Regeneration Methods for Peptide-Based QCM Biosensors in VOCs Analysis Applications
PublicationCleaning a quartz crystal microbalance (QCM) plays a crucial role in the regeneration of its biosensors for reuse. Imprecise removal of a receptor layer from a transducer’s surface can lead to unsteady operation during measurements. This article compares three approaches to regeneration of the piezoelectric transducers using the electrochemical, oxygen plasma and Piranha solution methods. Optimization of the cleaning method allowed...
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Divulging the anti-acetylcholinesterase activity of Colletotrichum lentis strain KU1 extract as sustainable AChE active site inhibitors
PublicationAlzheimer’s disease (AD), also called senile dementia is a neurodegenerative disease seen commonly in the elderly and is characterised by the formation of β-amyloid plaques and neurofbrillary tangles (NFT). Though a complete understanding of the disease is lacking, recent studies showed the role of the enzyme acetylcholinesterase (AChE) in pathogenesis. Finding new lead compounds from natural sources has always been a quest for...
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Diurnal variability of atmospheric water vapour, precipitation and cloud top temperature across the global tropics derived from satellite observations and GNSS technique
PublicationThe diurnal cycle of convection plays an important role in clouds and water vapour distribution across the global tropics. In this study, we utilize integrated moisture derived from the global navigation satellite system (GNSS), satellite precipitation estimates from TRMM and merged infrared dataset to investigate links between variability in tropospheric moisture, clouds development and precipitation at a diurnal time scale. Over...
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CHEMOTHERAPY-MEDIATED COMPLICATIONS OF WOUND HEALING. AN UNDERSTUDIED SIDE EFFECT
PublicationSignificance: Chemotherapy is a primary method to treat cancer, but while cytotoxic drugs are designed to target rapidly dividing cancer cells, they can also affect other cell types, including dermal cells and macrophages involved in wound healing, which often leads to the development of chronic wounds. The situation becomes even more severe when chemotherapy is combined with surgical tumor excision. Recent advances: Despite its...
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The early failure of the gamma nail and the dynamic hip screw in femurs with a wide medullary canal. A biomechanical study of intertrochanteric fractures
PublicationBackground: Intertrochanteric fractures may occur in a bone with a wide medullary canal that may lead to significant mobility of a intramedullary nail, contrary to an extramedullary device. This study evaluates the Dynamic Hip Screw and the gamma nail in AO 31.A2.1 fractures in these circumstances. Methods: Synthetic femora with canals drilled to 18 mm were used. Five fixation types were examined: a 2 - hole and a 4 – hole Dynamic...
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Rewitalizacja dróg wodnych delty Wisły jako podstawa nowej perspektywy osiedleńczej
PublicationW artykule opisano badania dotyczące rewitalizacji dróg wodnych Delty Wisły. Problematyka badawcza dotyczy rozwoju obszaru na styku lądu i wody. Wpływ lokalizacji nadmorskiej, i związana z nią problematyka wynikająca z położenia poniżej poziomu morza są dostrzegalne nawet do stu kilometrów od wybrzeża. Dodatkowym aspektem, który ujemnie wpływa na rozwój obszaru delty po II wojnie światowej jest utrata tożsamości regionalnej. Dlatego...
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E-technologie w diagnozie i pomiarach postępów terapii dzieci z autyzmem w Polsce
PublicationCelem artykułu jest przeanalizowanie możliwości wsparcia technologicznego - w szczególności z wykorzystaniem urządzeń mobilnych - diagnozy i oceny postępów terapii dzieci z autyzmem. W ramach badań dokonano przeglądu istniejących rozwiązań wspierających diagnozę i pomiar postępów terapii oraz przeprowadzono ankietę w polskich ośrodkach zajmujących się pracą z osobami dotkniętymi autyzmem. Wyniki badania wskazują na zainteresowanie...
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Ekonomiczne aspekty zastosowania techniki Mobilnych Pomiarów Satelitarnych przy regulacji osi toru
PublicationOd 2009 roku interdyscyplinarny zespół naukowy Politechniki Gdańskiej i Akademii Marynarki Wojennej (a obecnie Akademii Morskiej w Gdyni) rozwija technikę Mobilnych Pomiarów Satelitarnych toru kolejowego. Technika ta polega na objeździe trasy ciągnikiem szynowym z przyczepą (wagonem-platformą) lub wózkami, z zainstalowanymi na tych pojazdach odbiornikami sygnałów satelitarnych. Umożliwia ona precyzyjne określenie współrzędnych...
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Rheological, Mechanical, Microstructural and Radiation Shielding Properties of Cement Pastes Containing Magnetite (Fe3O4) Nanoparticles
PublicationThis work examines the influence of iron oxide nanoparticles (Fe3O4 NPs) on neutron and gamma-ray radiation shielding characteristics of Portland cement paste. Experimental evaluations were supplemented with theoretical studies using NXCom program. Portland cement pastes with 5, 10, 15, 20, and 30 wt% of nanomagnetite cement replacement were produced. Moreover, rheological, early strength development, compressive strength, and...
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The impact of training and neurotrophins on functional recovery after spinal cord transection: cellular and molecular mechanisms contributing to motor improvement
PublicationBeneficial effects of locomotor training on the functional recovery after complete transection of the spinal cord indicate that in chronic spinal animals spontaneous recovery processes are enhanced and shaped by the training. The mechanisms of that use-dependent improvement are still not fully understood. This review tackles three aspects of this issue: (1) neurochemical attributes of functional improvement...
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Bridge of Knowledge: an Internet platform for R2R and R2B transfer of knowledge and promotion of cooperation
PublicationCurrently, the European Commission puts emphasis on supporting collaboration between universities and business. There are many possible ways to create a strong relationship between both these parties. Positive results of such cooperation lead to increased competitiveness of the global market and, in consequence, bring significant growth of innovation. The cooperation between research-to-research (R2R) and research-to-business (R2B)...
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Risk Modelling with Bayesian Networks - Case Study: Construction of Tunnel under the Dead Vistula River in Gdansk
PublicationThe process of decision-making in public procurement of construction projects during the preparation and implementation phases ought to be supported by risk identification, assessment, and management. In risk assessment one has to take into account factors that lead to risk events (background info), as well as the information about the risk symptoms (monitoring info). Typically once the risks have been assessed a decision-maker...
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Positive management of the university
PublicationAbstract: The prevailing view held at contemporary Polish universities is that their main goal is to achieve effects measured by indicators, which applies to each element of their mission: education, research and the third mission, whereas the means to accomplish this goal consists of increasing the requirements and motivating by the “carrot and stick” approach. That approach discounts the importance of building a positive relationship...
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Multi-region fuzzy logic controller with local PID controllers for U-tube steam generator in nuclear power plant
PublicationIn the paper, analysis of multi-region fuzzy logic controller with local PID controllers for steam generator of pressurized water reactor (PWR) working in wide range of thermal power changes is presented. The U-tube steam generator has a nonlinear dynamics depending on thermal power transferred from coolant of the primary loop of the PWR plant. Control of water level in the steam generator conducted by a traditional PID controller...
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The effect of Ag, Au, Pt, and Pd on the surface properties, photocatalytic activity and toxicity of multicomponent TiO2-based nanomaterials
PublicationMulticomponent TiO2-based nanomaterials (MC-NMs) show better physicochemical properties than their individual components or bulk materials. However, the same unique properties that offer innovative applications might also pose unknown risks to human health and the environment. In this context, TiO2- based nanomaterials with a mixture of noble metal precursors (Ag, Au, Pt, and Pd) for large-scale technological applications in air...
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Dynamic analysis of temporary steel grandstand subjected to human-induced excitations due to jumping
PublicationSteel grandstands are structures that are frequently used during sport games and many other non-sporting events, such as festivals, music concerts, or even politicians rallies, with participation of a large number of attendees. Unfortunately, the presence of unexpected excessive dynamic loads due to unpredictable behaviour of spectators (e.g. synchronized harmonic jumping or swaying) may lead to...
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Determination of Peak Impact Force for Buildings Exposed to Structural Pounding during Earthquakes
PublicationStructural pounding between adjacent, insufficiently separated buildings, or bridge segments, has been repeatedly observed during seismic excitations. Such earthquake-induced collisions may cause severe structural damage or even lead to the collapse of colliding structures. The aim of the present paper was to show the results of the study focused on determination of peak impact forces during collisions between buildings exposed...
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Synthesis, structural characterization, and thermal properties of Ca‐ and La‐doped soda‐lime glasses by laser melting
PublicationLaser melting techniques have been used in the preparation of unconventional glass compositions with high melting temperatures. Thus, we wanted to test the feasibility of using a CO2 laser in the preparation of nitrogen-rich oxynitride glasses and nitride silicate glasses. Melting from oxides and metallic raw materials, we wanted to study first glass formation and possible evaporation losses of the glass components. Two glass series...
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Orbital blowout trauma occurring at the workplace – clinical, biomechanical and legal aspects
PublicationIntroduction and objective: Craniofacial injury at the workplace may lead to orbital blowout fractures. The aim of the study is the development of own numerical model of the eye orbit, assessment of the damage zones, and comparing them with clinical examinations. In addition, the current legal status of patients after injuries is presented Material and methods: In laboratory tests performed on bones collected from the upper and...
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The effect of fishing basin construction on the behaviour of a footbrdge over the port channel
PublicationThe paper analyses possible causes of failure of the rotating footbridge over the Ustka port channel. In July, 2015, strange behaviour of this object was observed in the form of excessive vibrations of bridge platform suspension rods, with the accompanying acoustic effects. A preliminary geotechnical analysis has revealed that this destructive effect was caused by the nearby construction works, namely construction of a fishing...
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Highly Dissipative Materials for Damage Protection against Earthquake-Induced Structural Pounding
PublicationIt is a common situation that seismic excitations may lead to collisions between adjacent civil engineering structures. This phenomenon, called earthquake-induced structural pounding, may result in serious damage or even the total collapse of the colliding structures. Filling the gap between two buildings erected close to one another by using visco-elastic materials can be considered to be one of the most effective methods to avoid...
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Aspects of intergranular corrosion of AISI 321 stainless steel in high-carbon-containing environments
PublicationPurpose – The purpose of this paper is to present a case study of unexpected sensitization to intergranular corrosion of highly resistant AISI 321 steel in petrochemical conditions, where it was subjected to the simultaneous influence of elevated temperature of 250°C and vapors from the asphalt production process. Design/methodology/approach – Corrosion coupons were exposed in an installation carrying asphalt vapors. To identify...
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Density functional theory calculations on entire proteins for free energies of binding: Application to a model polar binding site
PublicationIn drug optimization calculations, the molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) method can be used to compute free energies of binding of ligands to proteins. The method involves the evaluation of the energy of configurations in an implicit solvent model. One source of errors is the force field used, which can potentially lead to large errors due to the restrictions in accuracy imposed by its empirical nature....
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Comparison of GC–MS and MEKC methods for caffeine determination in preworkout supplements
PublicationIn this study, GC–MS- and MEKC-based methods for determination of caffeine (CAF) in preworkout supplements were developed and validated. The proposed protocols utilized minimal sample preparation (simple dilution and syringe filtration). The developed methods achieved satisfactory validation parameters, i.e. good linearity (R2 0.9988 and R2 0.9985 for GC–MS- and MEKC-based method, respectively), satisfactory intraand interaccuracy...
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Influence of the low ambient temperature on the start-up process of hydraulic pumps
PublicationStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of pressure drop in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump working chambers with...
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Genotoxicity of selected pharmaceuticals, their binary mixtures, and varying environmental conditions – study with human adenocarcinoma cancer HT29 cell line
PublicationPharmaceutical residues are present in the environment in mixtures and their adverse effects may also result from interactions that occur between compounds. Studies presented in this work focus on genotoxicity of pharmaceuticals from different therapeutic groups in mixtures and in individual solutions impacted with different environmental conditions assessed using comet assay (alkaline approach). Binary mixtures of pharmaceuticals...
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Impact of digital signal processing on FOC current feedback in high-speed PMSM drive
PublicationIn applications where size and weight of the electric motor are among major design concerns, Permanent Magnet Synchronous Motors (PMSMs) with wide operational speed-range are commonly preferred. Due to limited inverter switching frequency, high-speed operation of a drive results in a low ratio between the switching frequency and the fundamental frequency of motor voltage. Such operating conditions have been recently identified...
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The semi-Markov model of the process of appearance of sea-going ship propupsion system ability and inability states in application to determining the reliablity of these systems
PublicationThe article presents possible application of the theory of semi-Markov processes in creating the eight-state model of the process of appearance of the propulsion systems ability and inability states on sea-going vessels performing transportation tasks in a relatively long operating time t (t → ∞). The model has been proved to be able to be successfully used for determining the reliability of the abovementioned systems. The probability...
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Time window based features extraction from temperature modulated gas sensors for prediction of ammonia concentration
PublicationElectronic gas recognition systems, in literature commonly referred as electronic noses, enable the recognition of a type and a concentration of various volatile compounds. Typical electronic gas-analyzing device consists of four main elements, namely, gas delivery subsystem, an array of gas sensors, data acquisition and power supply circuits and data analysis software. The commercially available metal-oxide TGS sensors are widely...
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Seasonal variability and morphological structure of bacteria in the Admiralty Bay (King George Island, Antarctic).
PublicationIntroduction: The aim of investigations was to state whether melting glaciers cause mass mortality of the sea stenohalyne organisms, what in consequence can lead to an increase of accumulation and growth of psychrophilic bacteria. It may be also that fresh melting water is unfavourable to the sea bacteria and front glacier's regions are not the areas of their intensive development. Methods: Field investigations were done in Admiralty...
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Experimental and numerical study on deformed steel columns subjected to impact load during earthquakes
PublicationThe soft-storey failure is one of the most typical types of damage observed in buildings during earthquakes. The failure of an upper soft storey of a structure results in large impact load acting on the lower floors and if the resistance of the structural members of the lower storeys is not sufficient it may further lead to progressive collapse of the whole building. The aim of the present paper is to investigate the dynamic behaviour...
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Social Entrepreneurship Research – Challenges, Explanations and Suggestions for the Field Development
PublicationEmploying critical review and reflection on the key literature in the area of entrepreneurship and management studies in social entrepreneurship field, this paper aims to outline the current challenges this field is facing, while introducing related explanations and suggesting required changes. The current field of social entrepreneurship research is at its nascent stage, which is determined by ongoing definitional debates and...
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Non-Isocyanate-Based Waterborne Polyurethanes
PublicationNon-isocyanate polyurethanes (NIPUs) are a greener alternative for the conventional polyurethanes synthesized using toxic and moisture-sensitive di- or polyisocyanates. The most often described method of NIPU synthesis involves the reaction of five-membered cyclic carbonates with amines, and resulting polymers containing primary and secondary hydroxyl groups (so they are also known as polyhydroxyurethanes), which can be further...
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Pharmaceuticals and another groups of emerging contaminants: Occurrence and sources in Admiralty Bay (King George Island, Maritime Antarctica)
PublicationEveryday live activities may introduce a wide range of chemicals into wastewater systems. In this study presence of selected types of pharmaceuticals from cardiovascular system group, nervous and muscolo-skeleton system group, antimicrobial agents, genitourinary and sex hormones were tested in the wastewater from H. Arctowski Antarctic station. Moreover, the receiver of discharged wastewater (Admiralty Bay) were also studied. Considering...
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Socioemotional Wealth (SEW) of Family Firms and CEO Behavioral Biases in the Implementation of Sustainable Development Goals (SDGs)
PublicationAgreed upon by the UN member states, Agenda 2030 assumes joint action for long- term sustainable development. These actions are focused on the implementation of 17 Sustainable Development Goals (SDGs), where actions are assumed to lead to the suppression of negative externalities of human activity. It is stressed that the objectives of sustainable development can only be achieved through deep institutional changes in most dimensions...
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CaO-based high temperature CO2 sorbents – Literature review
PublicationThe use of CaO-based adsorbents has a high potential to capture CO2 from various systems due to its high reactivity with CO2, high capacity, and low cost of naturally derived CaO. The application of CaO-based sorbents to remove carbon dioxide is based on a reversible reaction between CaO and CO2. However, multiple carbonation/calcination cycles lead to a rapid reduction in the sorption capacity of natural CaO, and therefore efforts...
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Tolerance-Aware Optimization of Microwave Circuits by Means of Principal Directions and Domain-Restricted Metamodels
PublicationPractical microwave design is most often carried out in the nominal sense. Yet, in some cases, performance degradation due to uncertainties may lead to the system failing to meet the prescribed specifications. Reliable uncertainty quantification (UQ) is therefore important yet intricate from numerical standpoint, especially when the circuit at hand is to be evaluated using electromagnetic (EM) simulation tools. Tolerance-aware...