University of Gdansk
  • Gdańsk, Poland
Recent publications
Since the beginning of the war in Ukraine, we have been accompanied by brutal images of its effects. In addition to the fact that it is intended to build awareness of the destruction of the nation and state, it is also a means of arousing emotions. Positive emotions: compassion, national pride of Ukrainians, but also negative ones, such as fear, starch, hatred of Russians. Emotions that accompany us during the speeches of the President of Ukraine or while following press reports are also the basis for building political knowledge about the war in Ukraine itself, but also the possibilities of individual countries in supporting Ukrainians defending their country. Emotions and political knowledge also mobilize the international community to help Ukraine fight the aggressor. The structure of the article is as follows: after the introduction and background information on the armed conflict in Ukraine, the authors will examine the relationship between the stimulation of negative emotions, and political knowledge and how these phenomena influence the mobilization of the international community in order to end the war in Ukraine and bring the aggressor to account. As to the factual side, the authors necessarily rely on open-source research such as Amnesty International and Human Rights Watch reports as well as journalistic analysis. The situation is still unfolding and every day new allegations are arising. This main part will be followed by some concluding remarks.
In the countries that emerged after the collapse of the USSR, the concept of patriotism is often used instrumentally in the public debate. It is worth noting that there is no single form of patriotism, and the way it is understood is evolving, also subject to generational changes. It is influenced by a number of economic, social and cultural factors. Russia’s aggression against Ukraine has revealed the enormous strength and determination of Ukrainian citizens in the fight for their freedom. Bearing the above in mind, the authors of the study set several basic cognitive goals. The first is an attempt to define how young Ukrainians understand the concept of patriotism and to present the dominant patriotic attitudes on the basis of the collected empirical data. The second, equivalent research goal, in turn, assumes establishing their attitude towards their homeland and assessing what changes have occurred in this field after the annexation of Crimea. Thus, in this article, the authors undertake, inter alia, an attempt to find answers to the following questions: what values and civic virtues are the most important for young Ukrainians and if and why are they ready to sacrifice in the fight for the independence of their country? The thesis of this study assumes that the last eight years of the war with Russia led to the consolidation of the national identity of young Ukrainians who, not only in the declarative sphere, but also through their daily activities and struggle, strongly identify with their homeland. The above considerations were carried out with the use of the comparative method, the method of observation and analysis of texts. In addition, the authors conducted interviews and a survey in which 1,000 respondents took part, and the reference group were young refugees from Ukraine.
Analysis of the qualitative signature of fatty acids in tissues of organisms is an increasingly utilized tool in studies of trophic ecology in aquatic and terrestrial ecosystems. Here, we studied a colonial waterbird, the black-headed gull Chroicocephalus ridibundus, nesting in three colonies. We aimed to investigate whether fatty acid composition of its eggs is affected by the location of the colony (reflecting the spatial variation in habitat composition and, in turn, female diet at the time of egg formation), and the egg laying sequence (reflecting the temporal variation in female diet). We found that the composition of fatty acids in eggs of black-headed gulls differed among colonies, but not among subsequent eggs within the clutch. We interpret these results in the context of spatial differences in the diet of females breeding in different colonies and a lack of temporal variation in the diet of individual females. The pattern of the ratio of omega-3 to omega-6 fatty acids reflected the contribution of aquatic/terrestrial prey to their diet, and was consistent with the area of water courses around the colonies. High levels of omega-6:omega-3 can promote inflammation and thus lead to increased susceptibility to antigens. Further studies with prey sampling are required to reconstruct the diet composition of females during egg formation in more detail.
Quantum interference phenomena are widely viewed as posing a challenge to the classical worldview. Feynman even went so far as to proclaim that they are the only mystery and the basic peculiarity of quantum mechanics. Many have also argued that basic interference phenomena force us to accept a number of radical interpretational conclusions, including: that a photon is neither a particle nor a wave but rather a Jekyll-and-Hyde sort of entity that toggles between the two possibilities, that reality is observer-dependent, and that systems either do not have properties prior to measurements or else have properties that are subject to nonlocal or backwards-in-time causal influences. In this work, we show that such conclusions are not, in fact, forced on us by basic interference phenomena. We do so by describing an alternative to quantum theory, a statistical theory of a classical discrete field (the `toy field theory') that reproduces the relevant phenomenology of quantum interference while rejecting these radical interpretational claims. It also reproduces a number of related interference experiments that are thought to support these interpretational claims, such as the Elitzur-Vaidman bomb tester, Wheeler's delayed-choice experiment, and the quantum eraser experiment. The systems in the toy field theory are field modes, each of which possesses, at all times, b o t h a particle-like property (a discrete occupation number) and a wave-like property (a discrete phase). Although these two properties are jointly possessed, the theory stipulates that they cannot be jointly k n o w n . The phenomenology that is generally cited in favour of nonlocal or backwards-in-time causal influences ends up being explained in terms of i n f e r e n c e s about distant or past systems, and all that is observer-dependent is the observer's k n o w l e d g e of reality, not reality itself.
Quantum correlations and nonprojective measurements underlie a plethora of information-theoretic tasks, otherwise impossible in the classical world. Existing schemes to certify such nonclassical resources in a device-independent manner require seed randomness—which is often costly and vulnerable to loopholes—for choosing the local measurements performed on different parts of a multipartite quantum system. In this Letter, we propose and experimentally implement a semi-device-independent certification technique for both quantum correlations and nonprojective measurements without seed randomness. Our test is semi–device independent in the sense that it requires only prior knowledge of the dimension of the parts. We experimentally show a novel quantum advantage in correlated coin tossing by producing specific correlated coins from pairs of photons entangled in their transverse spatial modes. We establish the advantage by showing that the correlated coin obtained from the entangled photons cannot be obtained from two two-level classical correlated coins. The quantum advantage requires performing qubit trine positive operator-valued measures (POVMs) on each part of the entangled pair, thus also certifying such POVMs in a semi-device-independent manner. This proof of concept firmly establishes a new cost-effective certification technique for both generating nonclassical shared randomness and implementing nonclassical measurements, which will be important for future multiparty quantum communications.
Background Pancreatic cancer is one of the leading causes of cancer death in Western societies. Its late diagnosis and resistance to chemotherapies result in a high mortality rate; thus, the development of more effective therapies for the treatment of pancreatic cancer is strongly warranted. Usnic acid (UA) is a secondary metabolite of lichens that shows modest antiproliferative activity toward cancer cells. Recently, we reported the synthesis of a UA pyrazole derivative, named 5, which was more active than the parent compound toward cervical cancer cells. Here, its anticancer potential has been evaluated in detail in other cancer cells, particularly pancreatic cancer cells. Methods The impact of UA and derivative 5 on cell viability, morphology, cell cycle, and death was assessed using the MTT test, electron microscopy, flow cytometry, and immunoblotting, respectively. The calcium ions level was detected fluorometrically. In vivo, the anticancer activity of 5 was evaluated in a murine xenograft model. Results Derivative 5 inhibited the viability of different cancer cells. Noncancerous cells were less sensitive. It induced the release of calcium ions from the endoplasmic reticulum (ER) and ER stress, which was manifested by cell vacuolization. It was accompanied by G0/G1 cell cycle arrest and cell death of pancreatic cancer cells. When applied to nude mice with xenografted pancreatic cancer cells, 5 inhibited tumor growth, with no signs of kidney or liver toxicity. Conclusions UA derivative 5 is superior to UA inhibiting the growth and proliferation of pancreatic cancer cells. ER stress exaggeration is a mechanism underlying the activity of derivative 5.
City managers search for new concepts of city development in order to satisfy growing demands and manage risk. The research assumes that city management requires the combination of ideas of sustainable development, a smart city and resilience. These three concepts are the components of the so-called “Fundamental Power of the City”. The aim of this paper is to present and test the operationalization of the new hybrid approach to city development through the index named the Fundamental Power of the City Index which includes 80 variables. The research applies six linear ordering methods to investigate the functionality of the Index. These are used to investigate each city’s performance and compare it with other cities by ranking them according to a chosen measure. The research considers 18 voivodship capital cities of Poland. The research draws attention to different approaches of development assessment although analysis shows that most linear ordering methods produce similar rankings. Investigation shows that human and social capital factors contribute to high positions in the ranking which is consistent with the development strategies formulated by the leading cities. The results of the analysis also identify the most urgent problems of the municipalities. The research confirms that the Fundamental Power of the City concept, by including the requirements for sustainable, smart and resilient cities, fills the gaps between them and provides a holistic approach to city management.
Source–filter theory posits that an individual's size and vocal tract length are reflected in the parameters of their calls. In species that mate assortatively, this could result in vocal similarity. In the context of mate selection, this would mean that animals could listen in to find a partner that sounds—and therefore is—similar to them. We investigated the social calls of the little auk (Alle alle), a highly vocal seabird mating assortatively, using vocalizations produced inside 15 nests by known individuals. Source- and filter-related acoustic parameters were used in linear mixed models testing the possible impact of body size. A principal component analysis followed by a permuted discriminant function analysis tested the effect of sex. Additionally, randomization procedures tested whether partners are more vocally similar than random birds. There was a significant effect of size on the mean fundamental frequency of a simple call, but not on parameters of a multisyllable call with apparent formants. Neither sex nor partnership influenced the calls—there was, however, a tendency to match certain parameters between partners. This indicates that vocal cues are at best weak indicators of size, and other factors likely play a role in mate selection.
This paper investigates the car enthusiasm of Polish residents during the second and fourth waves of the pandemic. We try to answer if the car enthusiasm has changed between October 2020 and October 2021. Furthermore, we looked into the attitudes and beliefs of respondents about transport modes and their use, their perceived quality of life, and their opinions about sustainability and ecological lifestyle. We use a computer-assisted web interview (CAWI) survey in two rounds (October 2020 and October 2021). For data analysis, a structural equation modeling (SEM) model was proposed. We observe important changes in car enthusiasm between those two waves of the pandemic. Firstly, car enthusiasm was higher in 2021 than in 2020. Secondly, it was positively correlated with the ecological orientation of respondents. Thirdly, Y-generation respondents were less car enthusiastic. Fourthly, the influence of life quality on car enthusiasm was stronger in the fourth pandemic wave than during the second one.
Purification of bacteriophage-expressed proteins poses methodological difficulties associated with the need to process entire culture medium volume upon bacteriophage-induced bacterial cell lysis. We have used novel capsule glycosylase-depolymerase (TP84_26 GD) from bacteriophage TP-84, infecting thermophilic Geobacillus stearothermophilus bacteria, as a representative enzyme to develop a method for rapid concentration and purification of the enzyme present in diluted crude host cell lysate. A novel variant of the polyethyleneimine (PEI)-based purification method was devised that offers a fast and effective approach for handling PEI-facilitated purification of bacteriophage-expressed native proteins. Due to the very basic nature of PEI, the method is suitable for proteins interacting with nucleic acids or acidic proteins, where either mixed PEI-DNA or RNA–protein complexes or PEI–acidic protein complexes are reversibly precipitated. (i) The method is of general use, applicable with minor modifications to a variety of bacteriophage cell lysates and proteins. (ii) In the example application, TP84_26 GD was highly purified (over 50%) in a single PEI step; subsequent chromatography yielded a homogeneous enzyme. (iii) The enzyme’s properties were examined, revealing the presence of three distinct forms of the TP84_26 GD. These forms included soluble, unbound proteins found in host cell lysate, as well as an integrated form within the TP-84 virion.
The seawater microbiome is crucial in marine ecosystems because of its role in food chains and biogeochemical cycles; thus, we studied the composition of the pelagic marine microbiome collected in the upper 50 m on the opposite sides of Fram Strait: Spitsbergen and Greenland shelves. We found out that it differed significantly, with salinity being the main environmental variable responsible for these differences. The Spitsbergen shelf was dominated by Atlantic Waters, with a rather homogenous water column in terms of salinity and temperature down to 300 m; hence, the marine microbial community was also homogenous at all sampled depths (0, 25, 50 m). On the contrary, stations on the Greenland shelf were exposed to different water masses of both Arctic and Atlantic origin, which resulted in a more diverse microbial community there. Unexpectedly, for the very first time, we identified cyanobacterium Prochlorococcus marinus in Arctic waters (Spitsbergen shelf, 75–77° N). Till now, the distribution of this cyanobacteria in oceans has been described only between 40° N and 40° S. Considering the accelerated rate of climate warming in the Arctic, our results indicated that the seawater microbiome can be viewed as an amplifier of global change and that the Atlantification is in progress.
We have previously shown that the extracellular domains of the four syndecans are intrinsically disordered, and adopt a wide range of conformations. We report here the building of coarse‐grained models of the extracellular domains of human syndecans 2 and 4 using small‐angle X‐ray scattering restraints. One, two or three heparan sulfate (HS) hexadecasaccharides, (IdoA[2S]GlcNS[6S]) 8 , were attached to three serine residues of the core proteins, resulting in eight variants for each syndecan that were used for all‐atom molecular dynamics (MD) simulations (0.5–1 µs). Syndecan‐4 had a larger conformational diversity than syndecan‐2, and remained extended during MD simulations in absence of HS whereas syndecan‐2 adopted more compact conformations. Their core proteins thus appeared to be structurally distinct. The HS chains also behave differently, the middle chain being more flexible in syndecan‐4, and the third chain being able to interact with the core protein regions mediating cell adhesion. The cell adhesion sites on both core proteins were flexible, with or without HS chains, the NXIP motif of syndecan‐2 being located in a particularly flexible region. In conclusion, the HS chains induce moderate changes in the conformational dynamics of both syndecans, depending on the number of HS chains and their location on the core protein, and on the core protein itself.
The device-independent paradigm has had spectacular successes in randomness generation, key distribution and self-testing, however most of these results have been obtained under the assumption that parties hold trusted and private random seeds. In efforts to relax the assumption of measurement independence, Hardy's non-locality tests have been proposed as ideal candidates. In this paper, we introduce a family of tilted Hardy paradoxes that allow to self-test general pure two-qubit entangled states, as well as certify up to 1 bit of local randomness. We then use these tilted Hardy tests to obtain an improvement in the generation rate in the state-of-the-art randomness amplification protocols for Santha-Vazirani (SV) sources with arbitrarily limited measurement independence. Our result shows that device-independent randomness amplification is possible for arbitrarily biased SV sources and from almost separable states. Finally, we introduce a family of Hardy tests for maximally entangled states of local dimension 4 , 8 as the potential candidates for DI randomness extraction to certify up to the maximum possible 2 log ⁡ d bits of global randomness.
Morquio disease, also called mucopolysaccharidosis IV (MPS IV), belongs to the group of lysosomal storage diseases (LSD). Due to deficiencies in the activities of galactose-6-sulfate sulfatase (in type A) or β-galactosidase (in type B), arising from mutations in GALNS or GLB1, respectively, keratan sulfate (one of glycosaminoglycans, GAGs) cannot be degraded efficiently and accumulates in lysosomes. This primary defect leads to many cellular dysfunctions which then cause specific disease symptoms. Recent works have indicated that different secondary effects of GAG accumulation might significantly contribute to the pathomechanisms of MPS. Apoptosis is among the cellular processes that were discovered to be affected in MPS cells on the basis of transcriptomic studies and some cell biology experiments. However, Morquio disease is the MPS type which is the least studied in light of apoptosis dysregulation, while RNA-seq analyses suggested considerable changes in the expression of genes involved in apoptosis in MPS IVA and IVB fibroblasts. Here we demonstrate that cytochrome c release from mitochondria is more efficient in MPS IVA and IVB fibroblasts relative to control cells, both under the standard cultivation conditions and after treatment with staurosporine, an apoptosis inducer. This indication of apoptosis stimulation was corroborated by measurements of the levels of caspases 9, 3, 6, and 7, as well as PARP, cleaved at specific sites, in Morquio disease and control fibroblasts. The more detailed analyses of the transcriptomic data revealed which genes related to apoptosis are down- and up-regulated in MPS IVA and IVB fibroblasts. We conclude that apoptosis is stimulated in Morquio disease under both standard cell culture conditions and after induction with staurosporine which may contribute to the pathomechanism of this disorder. Dysregulation of apoptosis in other MPS types is discussed.
In this paper, we propose an ensemble classifier extended from a specialized bicriterion balancing algorithm originally proposed by the authors for binary imbalanced classification. The approach uses two specialized criteria for oversampling - classification potential and distance from the borderline between minority and majority instances. For mining multiclass imbalanced datasets the bicriteria oversampling algorithm was adapted to the needs of the multiple class problems using the one-versus-one (OVO) approach and the Adaboost technique. To evaluate the performance of the proposed ensemble classifier we use several state of the art balancing algorithms. The computational experiment shows a very good performance of the proposed approach.
Sea ice-waves interactions have been widely studied in the marginal ice zone, at relatively low wind speeds and wave frequencies. Here, we focus on very different conditions typical of coastal polynyas: extremely high wind speeds and locally-generated, short, steep waves. We overview available parameterizations of relevant physical processes (nonlinear wave-wave interactions, energy input by wind, whitecapping and ice-related dissipation) and discuss modifications necessary to adjust them to polynya conditions. We use satellite-derived data and spectral modelling to analyze waves in ten polynya events in the Terra Nova Bay, Antarctica. We estimate the wind-input reduction factor over ice in the wave-energy balance equation at 0.56. By calibrating the model to satellite observations we show that exact treatment of quadruplet wave-wave interactions (as opposed to the default Discrete Interaction Approximation) is necessary to fit the model to data, and that the power n>4 in the sea-ice source term S_ice~f^n (where f denotes wave frequency) is required to reproduce the observed very strong attenuation in spectral tail in frazil streaks. We use a very-high resolution satellite image of a fragment of one of the polynyas to determine whitecap fraction. We show that there are more than twofold differences in whitecap fraction over ice-free and ice-covered regions, and that the model produces realistic whitecap fractions without any tuning of the whitecapping source term. Finally, we estimate the polynya-area-integrated wind input, energy dissipation due to whitecapping, and whitecap fraction to be on average below 25%, 10% and 30%, respectively, of the corresponding open-water values.
Natural interactions among multiple quantum objects are fundamentally composed of two-body terms only. In contradistinction, single global unitaries that generate highly entangled states typically arise from Hamiltonians that couple multiple individual subsystems simultaneously. Here, we study the time to produce strongly nonclassical multipartite correlations with a single unitary generated by the natural interactions. We restrict the symmetry of two-body interactions to match the symmetry of the target states and focus on the fastest generation of multipartite entangled Greenberger-Horne-Zeilinger (GHZ), W, Dicke, and absolutely maximally entangled (AME) states for up to seven qubits. These results are obtained by constraining the energy in the system and accordingly can be seen as state-dependent quantum speed limits for {\color{black}symmetry adjusted} natural interactions. They give rise to a counter-intuitive effect where the creation of particular entangled states with an increasing number of particles does not require more time. The methods used rely on extensive numerical simulations and analytical estimations.
The Younger Dryas-Holocene transition represents a period of significant thermal change, comparable in magnitude to modern warming, yet in a colder context and without the effect of anthropogenic disturbance. This is useful as a reference to tackle how biodiversity is affected by temperature in natural conditions. Here, we addressed the thermal change during this period in a southern Baltic coastal lake (Konarzewo Lake, Poland), as inferred by chironomid remains. We evaluated changes in chironomid communities and used Hill numbers to explore how commonness and rarity underlie biodiversity changes attributable to warming. We found evidence of warming at Konarzewo Lake during the Younger Dryas-Holocene transition, with inferred temperatures in the Younger Dryas period supporting the NW–SE gradient in Younger Dryas summer temperatures across Europe. Chironomid communities drastically changed during the thermal transition. However, Hill numbers showed no response to temperature when rare morphotypes were emphasized (order q = 0) or a weak response when they were balanced with common morphotypes (order q = 1). Hill number of order q = 2, emphasizing the most common morphotypes, consistently increased with temperature across different sample sizes or coverages. This illustrates how common morphotypes, rather than the rare ones, may boost biodiversity facing warming.
The transport system is a crucial component of economic development in any country. Bosnia and Herzegovina, being a country with a diverse topography, faces unique challenges and opportunities in the transport system. This paper examines the potential challenges and opportunities of the transport system in Bosnia and Herzegovina and its role in economic development. Using a qualitative research approach, we conduct an in-depth analysis of existing literature and collect primary data through semi-structured interviews with key stakeholders in the transport industry in Bosnia and Herzegovina. Our findings indicate that the transport system in Bosnia and Herzegovina faces significant challenges, including inadequate infrastructure, lack of modernization, limited investment, and weak institutional framework. However, there are opportunities for the development of the transport system including its strategic location as a transit hub, potential for infrastructure improvements, and its unique natural resources that can be leveraged for tourism and sustainable development. The development of the transport system can also lead to increased trade and investment, job creation, and improved social welfare. To fully realize the potential of the transport system in Bosnia and Herzegovina, policymakers and stakeholders need to work together to address the challenges and leverage the opportunities. This paper provides policy recommendations for improving the transport system, including investment in infrastructure, modernization of the transport sector, institutional strengthening, and the promotion of sustainable development. The findings of this study have significant implications for the economic development of Bosnia and Herzegovina, and countries with similar challenges and opportunities in the transport sector.
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4,941 members
Magda Caban
  • Faculty of Chemistry
Marcin Wolek
  • Department of Transport Market
Katarzyna Wojczulanis-Jakubas
  • Department of Vertebrate Zoology
J. N. Izdebska
  • Department of Invertebrate Zoology and Parasitology
Kazimierz Musial
  • Institute of Scandinavian and Finnish Studies
Bażyńskiego 8, 80-309, Gdańsk, Poland
Head of institution
Piotr Stepnowski