On September 25–29, 2023, the LXIX Open Seminar on Acoustics OSA2023 was held in Karpacz. The conference was organized by the Wroclaw Branch of the Polish Acoustical Society (PTA). Simultaneously with the OSA2023 conference two accompanying events were held: Signal Processing Symposium SPSympo23 and 5th Polish-German Structured Conference on Acoustics PGSCA2023. 240 specialists from Poland and abroad took part in the OSA2023, SPSympo23, and PGSCA23 conferences delivering 96 papers and 6 plenary presentations.

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics.

Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points.

Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.

On behalf of Upper Silesian Division of the Polish Acoustical Society (main organizer) and Committee of Acoustics of the Polish Academy of Sciences (coorganizers) we are pleased to announce that according to many years of tradition the above-mentioned Conferences known as “Winter Schools” have been organized and carried out.
50th Jubilee Winter School on Wave and Quantum Acoustics constituted platforms for sharing the results and achievements obtained in different branches of physical acoustics (e.g. molecular acoustics, relaxation processes, quantum acoustics, acousto-optics, magnetoacoustics, photoacoustics, acoustics of solid state, acoustic emission etc.). Conference consisted of 17th Workshop on Acoustoelectronics and 17th Workshop on Molecular Acoustics, Relaxation and Calorimetric Methods.
XLVIXth Winter School on Environmental Acoustics and Vibroacoustics was the forum for all environmental and vibroacoustics fields. Particularly it concerned traffic noise, vibroacoustics of machines, room acoustics, building acoustics, noise protection and similar problems.
Celebrations of the “Golden Jubilee included:
• Jubilee Session with plenary lecture “The Golden Jubilee of the 50th Winter School on Wave and Quantum Acoustics – historical reminiscences” presented by prof. Tadeusz Pustelny and numerous touching addresses,
• Special Session “50 years have gone by ... – an evening of remembrance” conducted by prof. Marzena Dzida; it was a very nice session, without time restrictions as to presentations and discussions and the real duration of this session was twice as large as planned. Finally, 52 people participated within Conferences presenting 44 lectures, reports and posters. In this issue one can find abstracts of some lectures and posters, which were presented during the Conferences.
We are pleased to announce that on 27 February – 2/3 March, 2023, we will organize the next “Winter Schools” containing the Lth Jubilee Winter School on Environmental Acoustics and Vibroacoustics and 51st Winter School onWave and Quantum Acoustics. Thus, just now we invite you to participate in this “Golden Jubilee” Conference.
We would like to invite scientific centres and groups to cooperate in organizing workshops on the subjects of their interests related to the theme of the Conference. Further information about Conferences is available on our website https://ogpta.pl/index.php/en/

This issue, Chronicles of a Pandemic, is a collection of 27 position statements published by the Interdisciplinary COVID-19 Advisory Team to the President of the Polish Academy of Sciences, set up in July 2020. This publication is our team’s second comprehensive compilation (after Understanding COVID-19) of information about SARS-CoV-2 and COVID-19. Published in September 2020, Understanding COVID-19 aimed to sum up the first months of the pandemic and prepare the public in Poland for the difficult fall and winter 2020–2021. The present study, in turn, was written after two years of the pandemic, which first began in Wuhan in December 2019. We hope that ongoing reports on the course of the pandemic and the dilemmas faced by the public will help us learn from those difficult and important experiences, should similar challenges arise in the future.

A Declaration of the Joint Symposium on Climate Change “Safeguarding Our Climate, Advancing Our Society” 10 December 2018.

The article discusses the temporary exhibition ‘Krieg. Macht. Sinn. Krieg und Gewalt in der europäischen Erinnerung’ that was inaugurated at the Ruhr Museum in Essen on 11th November 2018, as part of the Horizon–2020 UNREST (Unsettling Remembering and Social Cohesion in Transnational Europe) project. In doing this, it succinctly engages with the theoretical framework underlying the concept of the exhibition, the so-called ‘agonistic memory’. Furthermore, addressed are some of the display selections made by the curators, which are explained by resorting to the aforementioned theoretical framework.

In 2014, an exhibition devoted to Islam in Brandenburg and Prussia was held at the Brandenburg-Preußen Museum in Wustrau, in the vicinity of Berlin. The exhibition was accompanied by a series of lectures, presentations, and workshops. Since 2017, the exhibition has been presented outside Germany, including in Kazan, the capital city of the Republic of Tatarstan, Russian Federation, where it arouses considerable interest. Among the many interesting objects, personal belongings of Tatar POWs who were caught by the Germans during the First World War have proved particularly attractive. A scientific conference on the traces of Tatars in Germany, covering archival resources and collective memory issues, has been another accompanying event.