In 1964, as an international principle for the protection of cultural heritage buildings and historical sites, the Venice Charter was adopted, affirming the important value and role of historical heritage buildings. The Charter refers to "our shared responsibility to protect them properly for future generations"(1). In the 2020 Sustainable Development Goals Reporti> issued by the United Nations, it is also proposed to "ensure by 2030 that all learners acquire the knowledge and skills needed to promote sustainable development" (2). Living cultural relics are the first witnesses of past history,which is the consensus of the world.
In the process of visiting the famous ancient temple in China,Lingyin Temple, had just been unblocked as the Covid-19 is severe in Hangzhou at that time. We found that the Buddhist stone statues are full of tiny cracks penetrating deep into the cultural relics, which will cause the cracks to expand and the cultural relics to collapse for a long time. Affected by Covid-19, many students and social groups cannot come here to learn Chinese Buddhist stone statue culture. However, if these cultural relics are not repaired in time, our descendants will no longer be able to see these vivid cultural relics that tell the history of our ancestors.
As a human practice team, we hope to focus on the repair of tiny cracks in cultural relics, provide new solutions for the restoration of stone cultural relics and propose our thinking and solutions in synthetic biology, architecture, history and anthropology. To this end, we carry out activities related to cultural heritage ethics, sustainable development, education and safety. Our main goal is to understand the current plight of tiny cracks in the field of stone relic restoration, and to introduce our plan to the public through field research in museums and Buddhist temples. We interviewed experts in different fields and paid attention to public speaking and communication with cultural heritage and museum practitioners, making our human practice more systematic and viable.
The public's positive attitude towards the application of synthetic biology methods to stone heritage conservation has increased our confidence in Story Light, but their concerns about heritage conservation ethics have also prompted us to conduct extensive research and interviews. From February to September, we conducted online＆offline interviews with experts in different fields,prompting us to think about the logical system of synthetic biology and cultural relics protection from the scientific, sustainable and ethical aspects.
We know that what really invigorate cultural relics is the public's enthusiasm for history and art, so we designed a questionnaire and sent it to various methods including online science popularization, interesting experiment open classes, lectures, face-to-face communication, etc. The interviewees included biologists, cultural relics and museum practitioners, and college students. We finally collected more than 200 questionnaires, ranging from high school to Ph.D. The questionnaires can basically reflect the interest of people of different ages and cultural levels in cultural heritage and their attitude towards the restoration of cultural relics with synthetic biology.
Fig 1 Overview of our questionnaire
On the questionnaire cover, we briefly describe the origins of inspiration, experimental design, and hardware support for our project to help respondents have an initial understanding of our project. All survey results are strictly protected by third-party platforms and us, and the information is only used for our project analysis and improvement. Questionnaires are listed here.
Fig 2 Age distribution of respondents (left) and Fig 3 Educational distribution of respondents (right)
Fig 4 Views on the current status of stone cultural relics protection in China
Fig 5 Views on the causes of damage to stone artifacts (left) and Fig 6 Views on traditional methods of restoring stone artifacts (right)
Fig 7 Views on the feasibility of our team's project
Fig 8 Key points of concern in microbial restoration of stone artifacts (left) and Fig 9 Views on the advantages of synthetic biology methods for restoring stone artifacts (right)
Through cross analysis of the questionnaire, we found that relatively speaking, the elderly and highly educated people would be more likely to show dissatisfaction with the current status of stone cultural relics protection. For this reason, we think that the dissatisfaction of this part of the population may be due to the fact that this part of the population has more rich life experience and social experience, and has more opportunities to learn about the real situation of stone cultural relics protection rather than the surface, which also suggests that our team needs to pay more attention to the education of young groups (link to education), so that they have more opportunities to contact the significant practical problem of stone cultural relics protection.
Fig 10 Opinions of people with different educational backgrounds on the status of stone cultural relics protection
Fig 11 Opinions of people of different ages on the status of stone cultural relics protection
At the same time, as mentioned earlier, the public's concern for the restoration of stone relics is mainly focused on the original restoration of stone relics, but most people believe that the traditional physical and chemical methods currently used cannot achieve this goal well. However, our cross analysis results show that young people with higher education are more inclined to accept the feasibility of new synthetic biology methods to repair stone relics, and believe that the original appearance of stone relics can be restored as much as possible by giving full play to the characteristics of synthetic biology.
We found that the middle-aged and old people who are less satisfied with the status quo of stone cultural relics protection also have a certain skepticism about synthetic biology methods, which well represents the idea of some of the public. Although they have a better understanding of the current status of cultural relics protection, they rarely have the opportunity to contact with the direction of scientific and technological progress. Based on this, we recognize that we should first confirm the feasibility of our scheme to experts and scholars in the industry and internalize their opinions.
After confirming the feasibility of the synthetic biology program to experts and scholars, we decided to conduct scientific publicity and education related to synthetic biology to the public. Through the analysis of the questionnaire, we obtained the hot words that the public cared more about, and decided to carry out the corresponding science popularization from the hot content that the public cared about. At the same time, considering that middle-aged and old people generally have the habit of browsing official accounts, our team decided to establish their own wechat official account and regularly deliver scientific content (link to wechat official account).
Fig 12 Opinions of people with different educational backgrounds on the use of synthetic biological methods to protect stone relics
Fig 13 Opinions of people of different ages on the use of synthetic biological methods to protect stone relics
Fig 14 Hot words mentioned by respondents
Based on the limitations of our questionnaire distribution, we tried some methods to make up for these limitations as much as possible. When holding offline activities, we talked with people representing different perspectives as much as possible, learned their views on the restoration of stone relics face to face, and incorporated their views into the process of our subsequent project design. At the same time, in the follow-up survey process, we simplified the survey topics as much as possible, hoping to expand the scope of respondents and reduce the bias of our survey results.
For the original data of the questionnaire that has been obtained, we not only made a simple statistical description of the results of the questionnaire, but also made a cross analysis of the original data of the questionnaire using statistical software, hoping to obtain the information we need as much as possible. Finally, we also used this information to help us make decisions on the key directions of publicity and education. Improvement and reflection.
Due to the pandemic, our team's questionnaires are mainly distributed through online channels, and the transmission channels are relatively simple; At the same time, our interviewees are mainly young people aged 18 to 25, which may be due to the limitations of the scope of transmission of our questionnaire, which may lead to the bias of the survey results.
Based on the limitations of our questionnaire distribution, we tried some methods to make up for these limitations as much as possible. When holding offline activities, we talked with people representing different perspectives as much as possible, learned their views on the restoration of stone relics face to face, and incorporated their views into the process of our subsequent project design. At the same time, in the follow-up survey process, we simplified the survey topics as much as possible, hoping to expand the scope of respondents and reduce the bias of our survey results. For the original data of the questionnaire that has been obtained, we not only made a simple statistical description of the results of the questionnaire, but also made a cross analysis of the original data of the questionnaire using statistical software, hoping to obtain the information we need as much as possible. Finally, we also used this information to help us make decisions on the key directions of publicity and education.
At the beginning of the project, our team members still had some unclear ideas about what synthetic biology is. Therefore, we interviewed Professor Li Yongquan, who specializes in synthetic biology of microorganisms at the School of Pharmacy, Zhejiang University. In the hope of visualizing the concept of synthetic biology, understanding and referring to cases where synthetic biology has been applied to solve specific problems.
Taking an iGEM project he once supervised as an example, Professor Li mentioned that the iGEM focuses on the project's thinking about both innovation and integrity. He said, "The key to a good project is telling a compelling scientific story." At the same time, Professor Li also suggested that the idea of synthetic biology is not a pile of Biobrick, and that the pathway is not the more complex the better. He said, " It's just a matter of reflecting the idea of the pathway in the overall design, and then specializing it in achieving one of your goals."
In response to our pathway design, Professor Li suggested that the spatiotemporal location of protein expression and codon preference of protein expression in prokaryotic cells are different from that in eukaryotic cells. Therefore, the project design needs to focus on whether the chassis we choose can successfully synthesise the target protein, and also whether the target protein is a secreted protein.
For the selection of chassis organisms, Professor. Li introduced that several alternative chassis organisms are generally selected for experimental comparison in research practice. And it’s also common to select the appropriate strain according to the target needs. For example, E. coli, which is commonly used in research laboratories, is not suitable to be used in precious stone artefacts or stone artefacts with high visitor traffic, as it is an infectious bacterium.
In response to Professor Li's advice, we incorporated the feedback into our design and selected the relatively harmless Bacillus subtilis as our chassis organism. We also confirmed that the target proteins ACCBP and EutM are secreted and can be correctly expressed by Bacillus subtilis. We are very grateful for the guidance we received from Professor Li in terms of synthetic biology ideas and application approaches.
In the construction of specific lines, we received the support of Yang Fan, associate professor of the School of Life Sciences, Zhejiang University.Prof. Yang has a lot of knowledge and experience in synthetic biology, and we maintained good communication and exchange with her throughout the project design and experiments. During the project design phase, we communicated closely with our teacher regarding the selection of the chassis organisms and the design of the population sensing module, taking into account the literature. During the experimental stage, Prof. Yang also gave advice on a series of problems arising during our experiments, which ensured the normal pace of our experiments.
In order to measure the practical application value of our heritage restoration, we invited Professor Ye Liang from the School of Civil and Architectural Engineering to answer our questions about heritage building repair, heritage building health monitoring and the development and application of restoration materials in heritage conservation.
Professor Ye Liang is the director of the Professional Committee of Cultural Relics Protection Technology and Restoration Materials of the Chinese Society of Cultural Relics, National registered first-class builder and national registered supervisor, San Francisco State University visiting scholar.
Prof. Ye Liang mentioned the issue of building strength of different materials, organic and inorganic materials have different aspects of repairing cracks in artifacts, and MICP produces calcium carbonate with certain strength properties. In addition, he guided us to think about the calcification efficiency of this amorphous calcium carbonate in the long term, the nature of calcium carbonate crystalline form at the bonding interface and the subsequent effects.
Through communication with Professor Yang Fan and Professor Ye Liang, we have a deeper understanding of synthetic biology methods and physical chemistry methods for cultural relic restoration. Therefore, we paid more attention to the problem of structural strength of restoration products during the experiment, and optimized our Design of Biomineralization Module.
After completing the construction of the basic gene circuit of the project, we began to think about the possible application scenarios of Story Light. Based on that, Based on this, we interviewed Professor Chaofeng Shen from the School of Environment and Resources of Zhejiang University. His main research interests are environmental microorganisms, environmental health, soil and groundwater remediation, and he is committed to solving complex environmental engineering problems with multidisciplinary ideas and knowledge. During the interview with Professor Shen, we learned that the tiny cracks in stone relics are a common problem that needs to be solved urgently. He encouraged us to consider and solve this problem through interdisciplinary thinking.It is possible to try to achieve the directional growth of engineered bacteria in the depths of tiny cracks through the combination of inorganic materials and engineered organisms.
In particular, he mentioned Gu Jidong, a professor at the Department of Marine Ecology and Biodiversity at the University of Hong Kong. Professor Gu is currently undertaking a research project on the restoration of the Little Angkor Wat ruins in Bangkok, Thailand using synthetic biology methods. Through Professor Shen's introduction, we learned that the use of synthetic biology for cultural relic restoration has a broad international space, which further strengthened our confidence.
Through the communication with Professor Shen, we considered the possibility of choosing inorganic chemical materials to enhance the swimming speed of engineering bacteria. Although we gave up this idea because of the low compatibility of the materials with Bacillus subtilis, this is our attempt to combine chemical materials with synthetic biology, which greatly benefited the team members. In addition, we further strengthened international exchanges, searched for the restoration of stone cultural relics around the world, and interviewed German anthropologist Professor Philip, which provided a valuable foundation for our follow-up promotion video and human practice work.
After ensuring the great feasibility of our project, we decided to carry out corresponding research on the foresight of the project to learn about the current situation of stone cultural relics protection and whether there are many problems such as great development potential in our project design.
Based on this, we interviewed Professor Yulan Hu from the School of Art and Archaeology of Zhejiang University. Professor Hu is from the Cultural Relics Protection Materials Laboratory of Zhejiang University. The laboratory was established in 1997 and has been focusing on the protection of cultural heritage for more than 20 years, especially the discussion of the corrosion and destruction mechanism (including microbial corrosion) of immovable cultural relics (ancient murals, brick, stone, soil relics, etc.) Research on the analysis of cultural relics materials and the development of cultural relics protection materials.
Professor Hu introduced us to the many methods currently used to protect cultural relics, and proposed that the conventional physical and chemical methods are mostly used at present. Considering that the use of synthetic biological methods to solve the problem of tiny cracks in stone relics is highly innovative and forward-looking.
Through Professor Hu's introduction, we compared the effects of Story Light's restoration of cultural relics with the widely used physical and chemical methods, and found that Story Light has irreplaceable advantages in terms of environmental protection and aesthetics in the repair of tiny cracks. Therefore, we adjusted the structure of some projects to highlight the sustainability of Story Light.
Through previous interviews and investigations, we have a relatively systematic understanding of the specific construction and application scenarios of Story Light, but due to the special interdisciplinary nature of cultural relic restoration, we hope that Story Light will find its own ethics in the humanities and social sciences.
Therefore, we contacted Associate Professor You Shujun from the School of History of Zhejiang University to discuss the historical significance of Story Light. We held a debate competition with the Zhejiang University School of Medicine debate team in the early stage: should the reconstruction of ancient monuments keep the original fabric/bring a modern appearance? When we asked her this question, Professor You, who offered the Forbidden City course, suggested that she prefers to restore the cultural relics according to their original appearance of its era.
After exchanging the principles of cultural relic restoration, we also hope to understand the status quo of cultural heritage protection between regions. As a Taiwanese historian, Professor You mentioned that the protection of cultural heritage in Taiwan was carried out earlier than that in mainland China. However, due to the humid climate, high temperature and rainy conditions, molds tend to grow, so the restoration of cultural relics faces greater challenges. Taiwan's population base is also not as large as that of mainland China, so public education on cultural heritage protection needs to be strengthened. In recent years, the production of documentaries and cultural and creative products around the Forbidden City in mainland China is a brand-new attempt to protect cultural relics in the new era, which is worthy of promotion.
Through exchanges with Professor You, we realized that the restoration of cultural relics not only needs to protect the physical structure of the cultural relics, but also needs to protect the original features of the cultural relics, which is consistent with the concerns raised by the public in our questionnaire survey. Therefore, we chose a biomineralization module that is more in line with the original materials of the stone cultural relics for repair, trying to avoid secondary damage to the cultural relics. In the promotion of the project, we chose a language that is more suitable for the public to preach, so that the design concept of Story Light is easier to understand, thus expanding our audience.
For the last stop of the interview, we chose the German anthropologist Prof. Philip. We hope to reconsider the rationality and philosophical significance of the restoration of cultural relics, and anthropology can provide us with such diverse perspectives. Professor Philip's research direction is "Old City Transformation and Cultural Heritage Protection from the Perspective of Anthropology". He proposed that the protection of cultural heritage should ultimately bring cultural relics back to people, so that cultural relics can truly come alive.
On the philosophical significance of the restoration of cultural relics that we are concerned about, Professor Philip used the protection of intangible cultural heritage as an example to explain. He pointed out that the public awareness of intangible cultural heritage in Germany is very low, and it is more unofficial protection, which originate from the traditional European countries (such as Greece and Italy) that attach importance to tangible heritage. In contrast, the United States established laws on the protection of intangible cultural heritage. China has even vigorously strengthened the protection of intangible cultural heritage at the official level. Therefore, the protection of tangible cultural relics also requires more official participation and public education.
In the end, Professor Philip told us that the focus of anthropologists' work in cultural heritage protection is not to think about the importance and significance of cultural heritage protection, but to observe cultural heritage protection itself from the perspective of a third party to think how it came about and how to create a relationship with the surrounding people. Finally, provide a third-party perspective for the society. Our research should not only focus on stakeholders, but the entire human community.
We were so impressed by Professor Philip's anthropological perspective that we were able to revisit the restoration of cultural relics. We gradually understand that as the carrier of human civilization, cultural relics, whether restored or not, will have an impact on the overall human society. The physical restoration of cultural relics is an important aspect, but the promotion and inheritance of the historical and artistic value of the cultural relics are equally important. Inspired by this, we will strengthen cooperation with more official organizations in the future, and devote ourselves to the promotion of cultural relics restoration, so that more people can understand the value of cultural relics.
In order to better understand the current research progress in the interdisciplinary intersection of biological, chemical techniques and heritage conservation, we met with Professor Zhang Bingjian's research team at the invitation of Associate Professor Hu Yulan, whom we had previously contacted. We systematically visited the laboratories related to heritage conservation research at the School of Art and Archaeology in ZJU. We learned from Professor Zhang that there is a boom in research on topics such as the testing of heritage components and the development of new fillers, so that there is a great need for talent with biochemical knowledge to join the heritage-related research. Professor Zhang's team includes research directions and tools from biology, chemistry and materials science.
Fig 15 College of Art and Archaeology, Zhejiang University. ZJU-China meet up with Professor Zhang’s research team.
For the conservation and restoration of stone artifacts, Zhang told us, “when using stone artifacts as restoration objects, we have to pay attention to the stone type of stone artifacts, as different stone types often correspond to different molecular arrangement characteristics. “ For example, the limestone commonly found in the Lingyin Temple area of Hangzhou, Zhejiang has a loose texture and many blind pores inside the stone, making it easy for water to leak through the micro-pores, causing the restoration material to lose water too quickly, which, for our project,means that the medium will lose water too quickly, making the biomineralization harder to achieve the final goal. In addition, the choice of materials is also very important. The organic epoxy resin used in earlier years tends to age and discolour, and the cement filler contains sulphides will damage the artifacts, so our restoration filler should be as similar as possible to the original chemical composition of the stone artifacts.
Fig 16A series of experimental work on heritage restoration carried out in Professor Zhang's laboratory
Professor Zhang also told us that restoration or conservation work on less damaged stone artifacts is currently a controversial matter. Nowadays, the term 'conservation damage' is being used more and more often. For example, one team tried using silicone to form a hydrophobic film on the surface of stone artifacts to slow down the erosion of the stone by acid rain, only to find that after a period of time the stone swelled hydrophilically, causing the top layer of stone to peel off along with the protective silicone film. This 'protective' measure accelerated the destruction of the stone. This is why the principle of 'minimum intervention' is now often applied to stone artifacts. Only with convincing proof-of-concept and realistic simulations, and with state approval before implementing conservation measures can we prevent 'conservation damage' to the maximum extent possible.
Finally, we discussed possible problems with the design of our project with Mr Li Qiang from the group. Mr. Li focuses on the production of self-healing materials by means of biomineralization. He expressed his long-term interest in our project and made the following suggestions for our project: (i) the open-air environment is different from the laboratory conditions, making it difficult to achieve the low oxygen conditions required to turn on the low oxygen promoter, so the products we develop in the application phase should take into account the limitations of complex environmental factors. (ii) It is important to keep an eye on the crystal structure precipitated by biomineralization, which must be calcite and not aragonite in order to act functionally as fracture repair. (iii) Due to the complexity of the environment, improving the efficiency of mineralization should be a priority in research to shorten the repair time by accelerating biomineralization.
This is a challenging journey of exploration. From the initial public-based questionnaire survey, to more professional expert surveys, and finally to field surveys, we have gained a deeper understanding of public needs, synthetic biology and cultural relic restoration. Through public surveys, we found that people have high expectations for the use of synthetic biology methods to restore cultural relics, and in the follow-up exchanges with experts, we further confirmed the feasibility and broad application space of Story Light. Especially in the final field investigation, we were affirmed by practitioners of cultural relics protection, which further strengthened our confidence.
Through systematic human practice exploration, we not only got a lot of help in the design of the experimental plan, but more importantly, we updated the idea of cultural relic restoration. We are deeply aware of the historical and artistic value of cultural relics and the status quo of cultural relic restoration around the world, and think about the significance of cultural relic restoration to all mankind. This will facilitate the subsequent entry of Story Light into the market and provide continuous assistance to the field of cultural relic restoration.
[1] UNESCO.Venice Charter.1964
[2] United nations.2020 Sustainable Development Goals Report.2020
[3] Niu Fei.Study on the Treatment Method of Pottery Crack-Taking A Pottery Soul Altar As An Example[M].Shenzhen Museum.2020,(08),55-60
