Nanosponges: As a Dynamic Drug Delivery Approach for Targeted Delivery

Recent advancements in nanotechnology have resulted in improved medicine delivery to the target site. Nanosponges are three-dimensional drug delivery systems that are nanoscale in size and created by cross-linking polymers. The introduction of Nanosponges has been a significant step toward overcoming issues such as drug toxicity, low bioavailability, and predictable medication release. Using a new way of nanotechnology, nanosponges, which are porous with small sponges (below one microm) flowing throughout the body, have demonstrated excellent results in delivering drugs. As a result, they reach the target place, attach to the skin's surface, and slowly release the medicine. Nanosponges can be used to encapsulate a wide range of medicines, including both hydrophilic and lipophilic pharmaceuticals. The medication delivery method using nanosponges is one of the most promising fields in pharmacy. It can be used as a biocatalyst carrier for vaccines, antibodies, enzymes, and proteins to be released. The existing study enlightens on the preparation method, evaluation, and prospective application in a medication delivery system and also focuses on patents filed in the field of nanosponges.Copyright © 2023 The Authors.

A droplet digital PCR chip with passive bubble removal for absolute nucleic acid quantification

Droplet digital polymerase chain reaction (ddPCR) is an extremely sensitive method for the precisely determining the concentration of target nucleic acids. However, air bubbles between droplets during amplification can cause significant droplet loss and decreased accuracy in results. In the present study, an all-in-one microfluidic chip that integrates emulsification, passive bubble removal, droplet monolayer storage, on-chip nucleic acid amplification, and droplet fluorescence signal readout is proposed. The integrated passive bubble removal structures automatically complete the trapping and guiding of the bubbles, ensuring that the droplets do not touch the bubbles during amplification and thus is not lost. The ddPCR device with optimized key parameters proved to be effective and efficient by completely removing bubbles between droplets and having a dead volume of less than 1 %. The ability of the ddPCR chip to accurately quantify nucleic acids was evaluated by measuring plasmids with the SARS-CoV-2N gene at concentrations ranging from 10 to 50 000 copies/μL. The innovative ddPCR device satisfies the requirement for accurate nucleic acid quantification and is expected to accelerate the popularity of dPCR due to its low processing difficulty, ease of use and high robustness.

Human-Centered Design in Response to a Pandemic: A Health System and Innovation Center Collaboration

Purpose of Study In the spring of 2020, the coronavirus pandemic brought new challenges to healthcare systems as the rising demand for protective equipment led to product and resource inequalities around the globe. The inability to safeguard workers led to increased infection rates and deaths of healthcare professionals worldwide. The purpose of this study is to evaluate the response of an in-house innovation committee to meet the unforeseen needs faced by healthcare systems during an acute medical crisis. Methods Used Housed directly within the University of Utah's health system (U Health), The Center for Medical Innovation (CMI) teamed up with the hospital's administration, BME, COVID task force, and occupational health to create an innovative think-tank to tackle the challenges brought in by the coronavirus pandemic, with the purpose of stratifying clinical needs based upon acuity, frequency, and urgency. While prioritizing equipment needs, CMI used human-centered design to analyze common industry practices, engineer comparable solutions from commercially available materials, test reimagined products against known gold-standards, and create open-source assembly guides that allowed others facing similar shortages to do the same. Summary of Results The close-working relationship between CMI and U Health allowed for the rapid identification, innovation, and engineering of products that met the needs of healthcare workers during the months following the COVID pandemic. Many of these were directly adopted in clinical settings, including aerosol containment tents, powered air-purifying respirators, and self-testing stations. Additionally, CMI identified and engineered 20 additional readily producible, rapid-response products in anticipation of future needs, such as a bubble CPAP, containment boxes, and re-usable PPE. From these, dozens of open source, 'Improvised Personal Protective Equipment' manuals were shared with global partners to address the inequality of medical equipment in lowresource settings. Conclusions The rapid development of easily-producible, lowcost solutions for acute clinical needs-especially those faced by the equipment shortages seen during a pandemic-is improved via the partnership between health systems and a center for medical innovation.

COVID caused a negative bubble. Who profited? Who lost? How stock markets changed?

Compiling a unique, worldwide collection of trading data, we analyze investor types' aggregate trading in stock markets throughout the COVID-19 episode, to assess investor types' role in a worldwide negative bubble and their degree of sophistication in responding to it. Individual investors were the main buyers and consequently the winners during the rebound. Foreign institutional investors exited host markets;some domestic institutions exploited the negative bubble by well-timed buying. In US index futures, asset managers heavily sold into crash;dealers profited from the rebound. Individual investors' buying was driven by their contrarian behavioral traits and a unique positive shock to retail investor demand for self-serviced investing in stocks, driven by work-from-home practices and unprecedented stimulus. This shock has changed the participant composition of world stock markets. Overall, the COVID-19 episode has many unique aspects that cannot be accounted for under existing theories.

Social Structural Prospects for the AI Era - Focusing on social structural problems

In this paper, I will detail the phenomenal problems involved in the AI era. Issues such as information bubble, post-truth, and digital prison will point to the problems that arise in an environment based on AI technology. This article will also show that, after Covid-19, the AI-based environment has changed not only as a technology as a tool for humans, but also as a condition for survival. From this, we diagnose the problems of control, monitoring, and subjection brought about by the development of AI technology and the changes to the living environment caused by the Covid-19 outbreak. Synthesizing these problematic situations, I argue that the AI-based environment is not designed to cause social change as a result of natural changes or technological progress, but as a kind of discipline mechanism. I believe that it is necessary to consider how this will affect the changes and development of human society, and that it is necessary to predict this through social structural changes. Through this process, I will discuss this concept by analogically applying them to the problems of the AI era. I would like to ask a fundamental question about whether the AI era will be able to achieve real progress for humans and human society. Moreover, through this comprehensive investigation, this article draws the conclusion that AI as a discipline device will play a critical role in producing new power. © 2022 University of Rijeka, Faculty of Medicine. All rights reserved.

Hybrid Opto‐Thermocycler for RT‐qPCR Detects SARS‐CoV‐2

Although real‐time quantitative reverse transcription polymerase chain reaction (RT‐qPCR) is the gold standard for detecting the virus severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) and other pathogens, the coronavirus disease 2019 (COVID‐19) pandemic has highlighted the scarcity of instruments, devices, and reagents for polymerase chain reaction (PCR) testing in constrained settings. At least for under‐resourced countries, it has become critical to deploy instruments that can be rapidly constructed and satisfy this demand. Instead of separating the optical system from the thermal module (typical of qPCR thermocyclers), we report a portable Hybrid Opto‐Thermocycler—dubbed HybOT Cycler—that takes advantage of the high‐temperature tolerances (>100 °C) of electronic and optical components to combine thermal control, illumination, and fluorescence detection into a highly integrated hybrid module. This simple configuration allowed us to reduce the overall number of components, thus simplifying its assembly and reducing the instrument size. The HybOT Cycler is wirelessly controlled from an application installed in a tablet. PCR assays are carried out in a bubble‐free microfluidic device that can be easily replicated from an acrylic mold. Using the HybOT Cycler, down to 100 copies/µL of genetic material of the virus SARS‐CoV‐2 with 95% sensitivity and 100% specificity is detected. The HybOT Cycler can assist in diagnosing SARS‐CoV‐2 and other pathogens in resource‐poor settings. [ FROM AUTHOR] Copyright of Advanced Materials Technologies is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Comparison of Effects of Salbutamol Inhalation with Continuous Positive Airway Pressure and Bubble Continuous Positive Airway Pressure Alone in the Management of Severe Transient Tachypnea of the Newborn

ABSTRACT Objective: To find the frequency of known risk factors in cases of severe transient tachypnea of the newborn (TTN) and to measure the effect of inhaled Salbutamol to bubble CPAP on required treatment duration. Study Design: Quasi-experimental study. Place and Duration of Study: Neonatal Intensive Care Unit, Combined Military Hospital, Malir Cantt, Karachi Pakistan, from Nov 2019 to Jun 2020. Methodology: A total of 60 cases of severe TTN, labelled on a predefined criterion were included in the study. The sample was randomized into two groups using an alternate sampling technique. Group-A was treated with bubble CPAP alone, while in Group-B, inhaled Salbutamol was added. The response was measured regarding the time taken to settle respiratory distress. Results: Out of 60 cases, 54(90.0%) were delivered through Caesarean section. A total of 9(15.0%) cases were born prematurely. Polycythemia was found in 10(16.6%) cases. Maternal asthma and gestational diabetes frequency were 8(13.33%) and 12(20.0%), respectively. A significant reduction was seen in the duration of respiratory distress in the study population receiving bubble CPAP with inhaled Salbutamol in the first 24 hours of illness (p-value<0.001). Conclusion: Caesarean section is the most significant risk factor for developing TTN. Adding Salbutamol nebulization to bubble CPAP resulted in an earlier settlement of respiratory distress.

Morphological Analysis of a Collapsing Cavitation Bubble near a Solid Wall with Complex Geometry

Featured Application: Collapsing cavitation bubbles can be used in material surface cleaning, the medical field, and so on. By adjusting the micro-jet intensity of the collapsing bubbles, the cavitation phenomenon can be employed to clean irregular material surfaces, such as sections, cracks, and vegetable leaves. In the medical field, cavitation bubbles can be used as microbubble contrast agents for ultrasound diagnostic imaging or vehicles for drug or gene delivery. The growth and violent collapse of cavitation bubbles can also be employed in sterilization or killing viruses such as COVID-19. The interaction mechanism between the cavitation bubble and a solid wall is a basic problem in bubble collapse prevention and application. In particular, when bubble collapse occurs near solid walls with arbitrarily complex geometries, it is difficult to efficiently establish a model and quantitatively explore the interaction mechanism between bubbles and solid walls. Based on the advantages of the lattice Boltzmann method, a model for cavitation bubble collapse close to a solid wall was established using the pseudopotential multi-relaxation-time lattice Boltzmann model. Solid walls with arbitrarily complex geometries were introduced in the computational domain, and the fractal dimension was used to quantify the complexity of the solid wall. Furthermore, owing to the lack of periodicity, symmetry, spatial uniformity and obvious correlation in this process, the Minkowski functionals-based morphological analysis method was introduced to quantitatively describe the temporal evolution of collapsing bubble profiles and acquire effective information from the process. The interaction mechanism between the bubble and solid wall was investigated using evolutions of physical fields. In addition, the influences of the solid walls' surface conditions and the position parameter on collapsing bubbles were discussed. These achievements provide an efficient tool for quantifying the morphological changes of the collapsing bubble. © 2023 by the authors.

Case study of the Beijing 2022 Olympic Winter Games: Implications for global mass gathering events amidst the COVID-19 pandemic.

Objective: This study aimed to evaluate the public health countermeasures against coronavirus disease 2019 (COVID-19) that are important for organizing mass gathering events (MGEs) during a pandemic and to identify the practices suitable for application at future MGEs. Methods: This study analyzed data from the Beijing 2022 Olympic Winter Games. The aforementioned analysis was conducted from the viewpoints of overseas stakeholders and Chinese residents. The comprehensive set of countermeasures established to prevent the transmission of the COVID-19 pandemic comprised the bubble strategy, the three-layer testing strategy (pre-departure testing, testing at the airport, and daily screening), the mandatory wearing of N95 masks, and mandatory vaccination. Findings: A total of 437 positive cases within the bubble were reported during the Games, of which 60.6% were detected through screening at the airport and 39.4% were detected through routine screening. Nearly, 92.0% of the positive cases were detected within 7 days of arrival in China, and 80.8% of the cases had already been identified before the Opening Ceremony of the Games. Outside the bubble, no Games stakeholders were infected and no spectator contracted COVID-19. The bubble strategy, the three-layer testing strategy, the mandatory wearing of N95 masks, and mandatory vaccination are promising countermeasures to prevent the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during MGEs. Conclusion: Public health countermeasures introduced during the Beijing 2022 Olympic Winter Games were proven to be useful. The success in delivering and organizing the Games instills confidence and leaves a public health legacy for future MGEs amid the pandemic of COVID-19 or future emerging infectious diseases.

Why are COVID-19 travel bubbles a tightrope walk? An investigation based on the Trans-Tasmanian case

The COVID-19 pandemic has hit the transportation sector hard;particularly air transportation, as a major mode of long-distance transportation, has been affected tremendously. Since the dawn of COVID-19, politicians and policy makers have discussed the idea of introducing travel bubbles between countries (or counties), to allow for a continued exchange of people and goods. The eponymous Trans-Tasmanian travel bubble is a major example, involving quarantine-free travel between Australia and New Zealand. While both countries have tried to form a travel bubble various times, recurring setbacks and difficulties were faced. In October 2021, this ambitious project presumably has come to an end, with both countries announcing the essential capitulation of their COVIDZero strategies and a planned opening towards broader international travel. In this study, we perform a close investigation of the history behind the Trans-Tasmanian travel bubble as an on-off relationship, identifying a set of drivers for the serious problems involving a sustainable setup and operation. We develop a framework which represents important factors for successful travel bubbles and believe that the satisfaction of all factors at once is extremely challenging. Our results and insights are not specific to the Trans-Tasmanian case only, although it is taken as a running example, but can be generalized to various scales and environments. We hope that our study contributes to the literature by improving our understanding of the highly buzzed travel bubble concept, while providing empirical evidence for the troubles that inherently make such bubbles a tightrope walk. © 2022 The Authors

An Investigation of the Effectiveness of Facebook and Twitter Algorithm and Policies on Misinformation and User Decision Making

Prominent social media sites such as Facebook and Twitter use content and filter algorithms that play a significant role in creating filter bubbles that may captivate many users. These bubbles can expose users to dangerous or extremist content as seen with QAnon rhetoric, leading to the January 6, 2021 attack on the U.S. Capitol, and the unprecedented propaganda surrounding COVID-19 vaccinations. This paper hypothesizes that the secrecy around content algorithms and their ability to perpetuate filter bubbles creates an environment where dangerous false information is pervasive and not easily mitigated with the existing algorithms designed to provide false information warning messages. Both Facebook and Twitter provide various forms of false information warning messages which sometimes include fact-checked research to provide a counter viewpoint to the information presented. The results of a survey administered by the authors indicate that users would spend less time on Facebook or Twitter once they understood how their data is used to influence their behavior on the sites and the information that is fed to them via algorithmic recommendations. Further analysis of the survey data indicates a possible correlation between having seen a false information warning message and COVID-19 vaccination status. © 2022 WMSCI.All rights reserved.

Pediatric Respiratory Distress Education in Ethiopia: Needs Assessment and Development of an Instructional Video Curriculum

BACKGROUND AND AIM: The COVID-19 pandemic both highlighted the importance of identifying respiratory distress and limited in-person training to develop such skills. Respiratory distress caused by infections represents significant pediatric morbidity and mortality in low- and middle-income countries. The aim of this study is to conduct a needs assessment on trainees' attitudes about the identification and management of pediatric respiratory distress. METHOD(S): A needs assessment was conducted with medical students and residents at the University of Gondar Hospital, Ethiopia. Topics included comfort with identifying and managing pediatric respiratory distress and preferred teaching methods. The means for each teaching method were calculated. RESULT(S): Seventeen trainees were surveyed, including medical students (n=3) and residents (n=14). Trainees were very or somewhat uncomfortable with identifying nasal flaring (29%) and cyanosis (24%). Trainees were very or somewhat uncomfortable with the concepts of emergency triage assessment and treatment for children in respiratory distress (29%) and with applying bubble continuous positive airway pressure (35%). Almost all trainees (92%) indicated a need for training on the identification and management of pediatric respiratory distress. Trainees ranked practical skills as the preferred teaching method, followed by hands-on simulation, videos, and written tests. Based on the needs assessment, a video curriculum was developed to address identified gaps in pediatric respiratory distress education. CONCLUSION(S): There is a need for curricula about pediatric respiratory distress for trainees in global health settings. We have developed an instructional video curriculum to be piloted in Ethiopia in 2022. Research is needed to evaluate the curriculum's pedagogic outcomes.

The Economic Consequences of Xi Jinping

In the aftermath of the 20th National Congress of the Chinese Communist Party, Xi Jinping’s principal focus will be on state and national security, while an entirely new economic- and financial-policy team, with little experience, will take charge of China’s troubled economy. Its members will have to manage several systemic problems – a debt mountain, a property bust, a rapidly ageing population, zero-COVID policies – and develop a viable new economic-development model. This would be a demanding agenda anywhere, but Xi’s China has to tackle it guided by an ever more devoutly Leninist approach to economic management, industrial policy and governance, at a time when China faces the most hostile external environment it has known since Mao Zedong, as exemplified by foreign decoupling. Although Xi’s China is capable of important accomplishments in science and technology, and of flexing its diplomatic and military muscles in defence of its interests, China’s politics may be much less capable of fixing the country’s systemic economic and financial weaknesses. The consequences of Xi Jinping’s economic programme, including an emphasis on self-reliance, promise to extend beyond China’s borders to foreign actors and countries that once benefited from its economic rise.

Bio-secure bubble during the COVID-19 pandemic to host the Asian Football Confederation (AFC) Champions League: A retrospective observational study.

Background and Aims: To describe the COVID-19 positivity rate among football players, team staff, and local organizing committee members participated in the Asian Football Confederation (AFC) Champions League (West) tournament organized with the Bio-secure bubble protocol in place. Methods: A retrospective observational study was carried out to include a total of 2184 participants during the AFC-West tournament in Qatar, which was a 3-week event (September 14-October 3, 2020). This event was undertaken under the Bio-secure bubble protocol, which was developed and implemented for sports events in Qatar during the pandemic. Within 72 h of departure and upon arrival in Qatar, all participants underwent reverse-transcriptase polymerase chain reaction testing (RT-PCR) to diagnose COVID-19. The test was considered positive based on the cycle threshold (cT) value which was <30, whereas, reactive if cT value was ≥30 and <40, and negative (cT > 40). Results: Of the 2184 participants (528 players, 388 team staff, and 1268 local staff), 916 international participants were tested for COVID-19 PCR upon arrival at the Hamad International Airport, whereas the local staff (n = 1268) were tested 2 days before entering the bubble. The mean age of the players was 27.5 ± 9.8. Fifteen teams participated and as many as 60 matches were played over 3 weeks. Most participants tested negative (95.3%) and 3.9% tests were inconclusive. During the entire tournament, the positivity rate was 2.7% among all participants. Of the total positive cases, 0.8% were positive before entering the bubble system. The remaining (1.9%) tested positive during the tournament phase (19 players, 16 team officials, and 8 organizing committee staff). Conclusion: Bio-secure bubble protocol operated in a controlled environment presents a minimal risk of COVID-19 infection for hosting international football events. This framework could be benchmarked to resume professional football competitions under unprecedented pandemic situations.

Swimming competitions in the era of COVID-19: Lessons from successfully hosting the International Swimming League.

Background: Organization of mass sport events in the COVID-19 era is utterly complicated. Containments measures, required to avoid a virus outbreak, force athletes to compete under circumstances they never experienced before, most likely having a deleterious effect on their performance. Purpose: We aimed to design a so-called athlete-friendly bubble system for the International Swimming League 2020 event, which is strict enough to avoid a COVID-19 outbreak, but still provides a supportive environment for the athletes. Methods: To avoid the feeling of imprisonment, athletes were permitted to spend a certain amount of time in the parks surrounding the hotels. Such alleviations were possible to apply with strict adherence to the hygienic and social distancing protocols and regular COVID-19 testing. Evaluation of every COVID-19 positive case was key, and if prolonged PCR positivity or false positive PCR result was identified, the unnecessary quarantine was planned to be lifted. Return to play protocol (RTP) was planned, in case of a COVID-19 infection of an athlete inside the bubble. To test, if the athlete-friendly system provided a supportive environment, we evaluated athlete performance. Results: 11,480 PCR tests were performed for 1,421 individuals. 63 COVID-19 positive cases were detected, of which 5 turned out to be clinically insignificant, either because of prolonged PCR positivity or because of a false positive result. 93.1% of the positive cases were detected in the local crew, while no athlete got infected inside the bubble, as the two infected athletes were tested positive upon arrival. RTP was provided for two athletes. 85% of the athletes showed improvement during the bubble and 8 world records were broken. Conclusion: The applied protocol proved to be effective, as no athlete got infected inside the bubble, moreover, the athlete-friendly system supported the athletes to improve their performance.

Development of bioreactors: current scenario and future challenges

Bioreactors since their invention have eased the feasibility of lab-scale processes to the industrial-scale level. They have been an integral part of the downstream processes. Apart from the product development, they have also been part of sustainable environmental practices such as reduction of wastage, treatment of waste products, wastewater, detoxification. The chapter focuses on the recent scenario of reactor development in terms of waste management. As the onset of the SARS-CoV2 pandemic has changed the course of action the bioreactors do have a major role to play in the handling of COVID waste as well. © 2022 Elsevier Inc. All rights reserved.

Hybrid Opto‐Thermocycler for RT‐qPCR Detects SARS‐CoV‐2

Although real‐time quantitative reverse transcription polymerase chain reaction (RT‐qPCR) is the gold standard for detecting the virus severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) and other pathogens, the coronavirus disease 2019 (COVID‐19) pandemic has highlighted the scarcity of instruments, devices, and reagents for polymerase chain reaction (PCR) testing in constrained settings. At least for under‐resourced countries, it has become critical to deploy instruments that can be rapidly constructed and satisfy this demand. Instead of separating the optical system from the thermal module (typical of qPCR thermocyclers), we report a portable Hybrid Opto‐Thermocycler—dubbed HybOT Cycler—that takes advantage of the high‐temperature tolerances (>100 °C) of electronic and optical components to combine thermal control, illumination, and fluorescence detection into a highly integrated hybrid module. This simple configuration allowed us to reduce the overall number of components, thus simplifying its assembly and reducing the instrument size. The HybOT Cycler is wirelessly controlled from an application installed in a tablet. PCR assays are carried out in a bubble‐free microfluidic device that can be easily replicated from an acrylic mold. Using the HybOT Cycler, down to 100 copies/µL of genetic material of the virus SARS‐CoV‐2 with 95% sensitivity and 100% specificity is detected. The HybOT Cycler can assist in diagnosing SARS‐CoV‐2 and other pathogens in resource‐poor settings. [ FROM AUTHOR]

The estimation of house bubbles during the time of pandemic: a study of Australia

While the economy slid into a recession since the onset of the COVID-19 pandemic, the house prices in many markets have reached historical highs. This research aims to examine how much the recent large increases in the prices can be explained by bubbles and whether the overvaluation is due to momentum or intrinsic bubbles. A present value model is constructed to estimate real estate bubbles with one dynamic and three assumed net rental yields. The empirical focus is on Sydney, Melbourne and Brisbane, the three largest residential property markets in Australia, that have experienced a rapid growth in house prices since the outbreak of coronavirus. The finding demonstrates the evidence of bubbles in all three markets during the study period but the degree of overvaluation varies. We also discover that momentum bubbles exist in these markets but the overvaluation is mainly explained by intrinsic bubbles.

Why are COVID-19 travel bubbles a tightrope walk? An investigation based on the trans-tasmanian case

The COVID-19 pandemic has hit the transportation sector hard;particularly air transportation, as a major mode of long-distance transportation, has been affected tremendously. Since the dawn of COVID-19, politicians and policy makers have discussed the idea of introducing travel bubbles between countries (or counties), to allow for a continued exchange of people and goods. The eponymous Trans-Tasmanian travel bubble is a major example, involving quarantine-free travel between Australia and New Zealand. While both countries have tried to form a travel bubble various times, recurring setbacks and difficulties were faced. In October 2021, this ambitious project presumably has come to an end, with both countries announcing the essential capitulation of their COVIDZero strategies and a planned opening towards broader international travel. In this study, we perform a close investigation of the history behind the Trans-Tasmanian travel bubble as an on-off relationship, identifying a set of drivers for the serious problems involving a sustainable setup and operation. We develop a framework which represents important factors for successful travel bubbles and believe that the satisfaction of all factors at once is extremely challenging. Our results and insights are not specific to the Trans-Tasmanian case only, although it is taken as a running example, but can be generalized to various scales and environments. We hope that our study contributes to the literature by improving our understanding of the highly buzzed travel bubble concept, while providing empirical evidence for the troubles that inherently make such bubbles a tightrope walk.

Art Market Investment Bubble during COVID-19—Case Study of the Rare Books Market in Poland

The literature provides information on the impact of the pandemic on various markets. Many articles suggest the necessity of diversifying investment portfolios during financial market turmoil. The article in a unique way analyzed the rare books market in Poland during the COVID-19 period. The results of rare books auctions (the largest players with 85% of the market share were taken into account) over the 2018–2022 period were considered. The authors presented the hypothesis that COVID-19 triggered an investment bubble which may burst quite suddenly after the pandemic period. The data presented confirm the hypothesis, showing sharp increases (up to 50%) in sales revenues and a subsequent collapse. Less spectacular results were obtained when analyzing the number of books offered and sold in a given period. The authors used descriptive measures as well as statistical tests. A simple model calculating possible revenue in conjunction with the WPDI (World Pandemics Discussion Index) indicator was also presented. © 2022 by the authors.