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Hunted or something else? Investigating ‘after-impact’ perforations in prehistoric seal scapulae from ˇSventoji, Lithuania
No full textAnimal scapulae bearing distinct holes (in some cases, even more than one or two) have been found in several European prehistoric sites and have mainly been associated with the hunter-gatherer-fisher communities. The genesis of such holes is usually interpreted unambiguously, i.e. they are considered to be associated with hunting, during which the scapula might have been hit with a point or harpoon. Artefacts of this type have been found in the Subneolithic sites in ˇSventoji (coastal Lithuania). This study discusses the results of the traceological studies of such scapulae and the experimental programme implemented for their needs. The microscopic analysis of the
impact marks of experimentally perforated scapulae created via various osseous and flint points forms the basis for studying the direction and angles in which the ˇSventoji scapulae could have been perforated. Thus, an alternative hypothesis for the genesis of holes on these artefacts is proposed, i.e. suggesting their connection with meat smoking or roasting.This research was funded by the National Science Centre Poland, project no. 2021/43/B/HS3/0050
Nagaoka ferromagnetism in moire triangular supperlattice complexes
No full textDecision No. 2021/41/B/ST3/03322We examine the finite-size twisted TMDs within a moire triangular lattice and analyze their magnetic properties above half-filling. By introducing one electron into a half-filled system, the total spin of the ground state can reach its maximum, leading to the emergence of Nagaoka ferromagnetism. This form of magnetism arises from correlation effects, essentially due to constructive interference among various manybody configurations. We employ exact diagonalization methods to solve the Hubbard Hamiltonian, fully accounting for these correlations. We demonstrate the emergence of Nagaoka ferromagnetism by adding one, two, and three electrons above half-filling, with the ferromagnetic characteristics varying based on the geometries of finite triangular lattices.Polish National Science Centre (NCN
Studies of Stability of Nagaoka Ferromagnetism on a Triangular Lattice
Full text linkDecision No. 2021/41/B/ST3/03322Moire superlattices can be created by stacking two atomic layers ofdifferent materials, and its electronic properties can be manipulated using easily adjustable external factors, such as the twist angle, making them promising candidates for quantum simulators. In this study, first we briefly examine the features of the triangular moire lattice of transition metal dichalcogenides (TMDs) by treating it as a periodic system through both continuum and tight-binding models. The primary aim isto investigate the magnetic characteristics by fully incorporating correlations, which is challenging in a periodic system due to the vast size ofthe Hilbert space. Therefore, we concentrate on finite-sized triangular lattices. We examine the finite-size twisted TMDs within a moire triangular lattice and analyze their magnetic properties above half-filling. By introducing one electron into a half-filled system, the total spin of the ground state can reach its maximum, leading to the emergence of Nagaoka ferromagnetism. This form of magnetism arises from correlation effects, essentially due to constructive interference among various many body configurations. We employ exact diagonalization methods to solve the Hubbard Hamiltonian, fully accounting for these correlations. We demonstrate the emergence of Nagaoka ferromagnetism by adding one, two, and three electrons above half-filling, with the ferromagnetic characteristics varying based on the geometries of finite triangular lattices. Additionally, the interaction strength is analyzed to observe transitions in total spin and assess system stability. The Nagaoka polaron is also visualized within the finite triangular lattices.Polish National Science Centre (NCN
Too hot to fear? Temperature modulates metabolic response of ectothermic prey to predation risk.
No full text1. Rising temperature may affect individual performance, e.g. due to metabolism modification. Another stressor affecting metabolism is predation pressure, commonly present in freshwater environments, but rarely integrated into temperature-related studies. Non-native species that evolved under harsh climatic conditions are likely to perform better at elevated temperature than their native counterparts, saving more energy resources for antipredator responses compared to more temperature-sensitive native counterparts. However, this could be further modified by the organism size, as metabolic rate scales with body mass.
2. We investigated interactive effects of temperature, predation risk and body mass on metabolic rate of two amphipod species with different evolutionary history: Gammarus pulex (Gammaridae), a common native taxon in European freshwaters, and Dikerogammarus villosus (Gammaridae), a non-native species in Western and Central Europe, originating from the Ponto-Caspian region. Using intermittent flow-through respirometry, we measured their oxygen consumption rate (a proxy for metabolic rate) along body mass gradient at different temperatures (15 versus 24 oC) and in the presence or absence of fish kairomones (Eurasian perch, a common predator for both amphipod species).
3. We discovered species-specific effects of temperature on body-mass scaling of metabolic rate. The metabolic rate of D. villosus was unaffected by temperature. In contrast, metabolic rate increased with temperature in small, but not in large individuals of G. pulex. Furthermore, metabolic rate of both species increased in the presence of predation risk at 15 oC, but not at 24 oC.
4. Our results showed that both amphipod species have a limited ability to adapt their metabolism to rising temperatures, except small G. pulex. Assuming that the higher metabolic rate enhances prey defence ability, the lack of metabolic response to predator kairomones of both species at the elevated temperature may lead to an imbalance in predator-prey interactions with ongoing global temperature increase.
5. We showed that increased temperature is challenging to both native and non-native amphipods, and temperature effect on the native species depends on its size. Moreover, our study demonstrates that temperature modifies the effect of other common environmental factors, such as predation risk, on amphipod metabolism. Thus, taking these additional factors into account, as well as considering full species size ranges due to size-depended thermal sensitivity, will improve our understanding of the true ecological consequences of global warming in freshwater ecosystems.Narodowe Centrum Nauki, grant nr 2020/39/D/NZ8/0122
The movement between countries without moving: A German minority community archive in Poland and its impacts and practices
Full text linkThe file contains presentation of a paper delivered during the 34th ICARUS Convention in Budapest, Hungary ("Archives Reflecting 21st century Challenges - Migration and Sustainability", 12-14.05.2025).The German Minority Research Center is a grassroots, non-governmental organization dedicated to researching and documenting the German minority in Poland, with particular emphasis on the formation of minority organizations after the turn in 1989/1990. The Center records and protects the history and identity of Germans in Poland. The paper aims to present the practices and impacts of this community archive, with a special focus on social and affective impacts. Moreover, the paper touches the challenges faced by the archive and how it strives for sustainability and resilience. Data were obtained through qualitative interviews conducted in August 2024, and through direct on-site observations and desk research.Narodowe Centrum Nauk
Flood occurrences and characteristics in Poland (Central Europe) in the last millennium
Full text linkIn the current era of global climate change, extreme events such as flood exposure are increasing globally. Knowledge about floods during historical periods is limited worldwide, mainly due to gaps in the documentary evidence and the lack of a reliable, comprehensive database. A new comprehensive database of floods in Poland in the 11th–18th centuries was created using quality-controlled documentary evidence. In addition, a list of floods for the 19th and 20th centuries was created based on a literature review. Using all these data, the frequency, intensity, genesis, and spatial distribution of floods in Poland in the last millennium were investigated. Results revealed the occurrence of 1680 floods in Poland in the last millennium. The 18th century was the most abundant in recorded floods (356, 21 %). Floods in the period 1001–1800 were most frequent in the Silesia region (553, 43 %) and in the Oder River basin (671, 55 %). The number of floods was greatest in summer (JJA, 46 %) and the lowest in autumn (SON, 8 %). An investigation of the origin of floods indicated that rain was the main contributing factor to the occurrences of floods in Poland (44 %). The estimation of the intensity of floods showed that most of them were of extreme nature: “above-average, or supra-regional flood” (33 %) and “extraordinary” floods (70 %). Analysis of the multi-temporal trend demonstrated that, overall, for the periods of 1501–1700 and 1601–1800, positive trends were more numerous than negative trends, whereas, for 1801–2000, negative trends were slightly more numerous than positive trends.This research was funded by a grant from the National Science Centre, Poland, project (no: 2020/37/B/ST10/00710) and "Excellence Initiative - Research University" program (IDUB) at the Nicolaus Copernicus University in Toruń, Poland
Changes in bioclimatic conditions on the coast of the Labrador Peninsula in the late 19th/early 20th century
No full textThe contemporary warming that we are observing on Earth is most intense in the Arctic and Sub-Arctic. Until the mid-20th century,
human impact on the Arctic environment and climate was small, so it is extremely important to understand these past conditions as
best as possible in order to better understand current and future changes. To date, there has been little work analysing the climate of
the Labrador coast dating back to the late 19th/early 20th century. In the case of bioclimatic studies, there are even fewer such works.
The main aim of this paper is to fill this gap. Changes in bioclimatic conditions in the northeastern part of the Labrador Peninsula were
estimated based on meteorological observations (air temperature, atmospheric pressure and wind speed) taken from six stations:
Hebron, Hoffenthal, Nain, Okak, Rama and Zoar. They were carried out three times a day (8:00, 14:00 and 20:00) by Moravian
missionaries on behalf of Deutsche Seewarte and in accordance with its standardised guidelines. Based on these meteorological
data, the following bioclimatic indices were performed and analysed: Wind Chill Temperature (WCT), Insulation Predicted (Iclp) and
atmospheric pressure stimulus. Bioclimatic conditions in the historical period were compared with the conditions occurring in the
modern period on the Labrador Peninsula.The work was supported by the National Science Centre, Poland project No. 2020/39/B/ST10/0065
'I am the generation that was said to turn off the lights.' The affective impact of a minority-based community archive
No full textThe file contains presentation of a paper delivered during the conference "A Polyphony of Emotions. Thinking Affect in Heritage, Memory and Material Culture" (Amsterdam, the Netherlands, 2-4.07.2025) organized by the Amsterdam School for Heritage, Memory and Material Culture, University of Amsterdam.Contrary to the perception of archives as objective and cold repositories, they are social, contextual constructs, which are shaped by people, and mutually, shape the people associated with them. One aspect of this two-way human-archive relationship is emotions. Affective impacts are particularly evident in community archives – grassroots, independent archival initiatives, overwhelmingly driven by such affects as passion, a sense of mission and a sense of (in)justice.
All these factors are connected with the German Minority Research Center – a community archive discussed in the paper. The archive is based in Opole, Poland (in the region of Silesia) and is focused on recording and preserving the history, identity and traditions of the German minority in Poland.
The paper presents what affective implications are carried by this independent heritage endeavor. Affective categories discussed in the paper are, e.g.: trust and mistrust; trauma; satisfaction; sense of mission; weariness; fear/concern.
The paper discusses investigations carried out as part of the project “The impact of independent community archives” (2023-2026; funding: National Science Center, Krakow, Poland), which aims to study and understand the social and affective impacts of grassroots archives in Poland. The project is designed as a multiple case study, with on-site visits to three Polish community archives and qualitative interviews with archivists, collaborators, donors and users.Narodowe Centrum Nauk
Virtual Reality in the Context of Opinions and Preparation of Teachers for Its Use in the Educational Process. A Large-Scale Survey
No full textVirtual reality (VR) is an interesting teaching tool that is increasingly being incorporated into the educational process. Thanks to VR goggles equipped with appropriate sensors and software, it is possible to support the educational process to various extents and at various levels. Of course, in order to achieve the expected results, it is important to properly prepare the teacher – the leader of the educational process. In the context of working with VR goggles, both knowledge and skills in using the new technology are important.At present, little is known about preparing teachers to work with VR technology. As a result, it was decided to conduct mixed research (qualitative and quantitative), verifying the level of knowledge and preparation of teachers to use VR technology in the educational process. As part of the procedure, teachers’ opinions on the possibilities of the educational use of virtual reality were also verified. The research was carried out using a survey sent to randomly selected schools. As a result, the research covered 870 teachers working in both primary and secondary schools. During the research, depending on the analysed values, the following were determined: mean, mode, median, Spearman’s rho correlation, and Cramer’s V correlation were used. The collected data have shown that teachers’ opinions on virtual reality are correlated with their age, gender, and the subject taught. Regarding the preparation of teachers to use VR goggles during education, it should be noted that approximately 74% of them have very low or low knowledge in this area. 18% of teachers have average knowledge of VR goggles, dedicated software, as well as the possibilities and principles of their use in the VR virtual space. On the basis of the collected data, it can be concluded that only 8% of teachers are adequately prepared to teach classes using VR goggles, and their knowledge in this area is at a good or very good level