Extraction of underwater fragile artifacts: research status and prospect

There are still many difficulties in the recovery and long-term preservation of underwater archaeological artifacts, in situ preservation should be the first choice before further procedures are considered. However, the materials, preservation status, and preservation environment of underwater artifacts are diverse, resulting in many fragile artifacts facing difficult situations. In order to prevent serious damage, it is a safe protective strategy to preserve them in a controlled environment for a long time after excavation. Extraction and transfer of fragile cultural relics are vital parts of this strategy. Due to the complexity of the underwater environment and the vulnerability of fragile artifacts, safety in extraction and transfer still faces enormous challenges. Researchers have developed new materials and technologies to tackle this problem. This paper focuses on introducing and developing prospects to different preservation techniques for fragile artifacts from underwater sites.

Cryoprotectant treatment tests on three morphologically diverse marine dinoflagellates and the cryopreservation of Breviolum sp. (Symbiodiniaceae)

Dinoflagellates are among the most diverse group of microalgae. Many dinoflagellate species have been isolated and cultured, and these are used for scientific, industrial, pharmaceutical, and agricultural applications. Maintaining cultures is time-consuming, expensive, and there is a risk of contamination or genetic drift. Cryopreservation offers an efficient means for their long-term preservation. Cryopreservation of larger dinoflagellate species is challenging and to date there has been only limited success. In this study, we explored the effect of cryoprotectant agents (CPAs) and freezing methods on three species: Vulcanodinium rugosum, Alexandrium pacificum and Breviolum sp. A total of 12 CPAs were assessed at concentrations between 5 and 15%, as well as in combination with dimethyl sulfoxide (DMSO) and other non-penetrating CPAs. Two freezing techniques were employed: rapid freezing and controlled-rate freezing. Breviolum sp. was successfully cryopreserved using 15% DMSO. Despite exploring different CPAs and optimizing the freezing techniques, we were unable to successfully cryopreserve V. rugosum and A. pacificum. For Breviolum sp. there was higher cell viability (45.4 ± 2.2%) when using the controlled-rate freezing compared to the rapid freezing technique (10.0 ± 2.8%). This optimized cryopreservation protocol will be of benefit for the cryopreservation of other species from the family Symbiodiniaceae.

The Link Between Climate Change and Digitization of Archives in South Africa

This chapter assesses the link between climate change and digitisation of archives in South Africa. The study found linkage between flooding, fire, and digitization of archives in the sense that records required long-term preservation to be accessible. The chapter focuses on converting paper-based records into digital platforms as a strategic role to prevent records from damage. Heritage institution such as the National Archives of South Africa is in the forefront of the preservation of archives in South Africa. It is their national mandate to preserve archival materials and make them accessible to various stakeholders. The success of digitization is dependent on the organisation strategy. This means that partnership, privacy, copyright need to be considered. The research found that most of the heritage institutions in South Africa lack digitization strategy, which led to loss of institutional memory.

Vitrification Cryo-Foil for Apple Cryopreservation and the Seesaw Effect Between Shoot Recovery and Virus Eradication

Improvements of existing cryopreservation protocols are necessary to facilitate long-term preservation of plant germplasm and the cryotherapy-effect of pathogen eradication. This study reported a vitrification (V) cryo-foil/plate methods for cryopreservation of shoot tips and cryotherapy effect in ‘Pink Lady’ apple. In V cryo-foil/plate protocols, shoot tips were first attached onto aluminum foils/plates using calcium alginate before other procedures. Shoot tips cryopreserved by V cryo-foil required 6.1 weeks to fully recover and 53% of shoot regrowth was obtained, comparable to the Dv cryopreservation. Similar regrowth levels were produced between applying V cryo-foil and Dv cryopreservation to another 4 Malus genotypes. Histological observations in shoot tips cryopreserved by Dv and V cryo-foil found only those with surviving apical dome and leaf primordia (LPs) could recover after cryopreservation. In apical meristem of shoot tips cryopreserved by Dv and V cryo-foil, higher surviving probability was detected from the V cryo-foil protocol, and the young LPs showed the highest level of surviving. Virus detection in cryo-derived plants showed apple stem grooving virus and apple chlorotic leaf spot virus were all preserved after cryopreservation, and higher eradication efficiency of apple stem pitting virus (70%) was produced by Dv than the 55% of V cryo-foil. These results supported applying V cryo-foil as an improvement to the widely applied Dv method in shoot tip cryopreservation, and also revealed a seesaw mode between shoot recovery and cryotherapy effect. Once the seesaw moves to increase the recovery after cryopreservation, the cryotherapy-effect on the other side would be decreased.

A 21st Century Technical Infrastructure for Digital Preservation

Digital preservation systems and practices are rooted in research and development efforts from the late 1990s and early 2000s when the cultural heritage sector started to tackle these challenges in isolation. Since then, the commercial sector has sought to solve similar challenges, using different technical strategies such as software defined storage and function-as-a-service. While commercial sector solutions are not necessarily created with long-term preservation in mind, they are well aligned with the digital preservation use case. The cultural heritage sector can benefit from adapting these modern approaches to increase sustainability and leverage technological advancements widely in use across Fortune 500 companies.

Metadata in the Digital Library

The range of metadata needed to run a digital library and preserve its collections in the long term is much more extensive and complicated than anything in its traditional counterpart. It includes the same 'descriptive' information which guides users to the resources they require but must supplement this with comprehensive 'administrative' metadata: this encompasses technical details of the files that make up its collections, the documentation of complex intellectual property rights and the extensive set needed to support its preservation in the long-term. To accommodate all of this requires the use of multiple metadata standards, all of which have to be brought together into a single integrated whole.<br><br><i>Metadata in the Digital Library </i>is a complete guide to building a digital library metadata strategy from scratch, using established metadata standards bound together by the markup language XML. The book introduces the reader to the theory of metadata and shows how it can be applied in practice. It lays out the basic principles that should underlie any metadata strategy, including its relation to such fundamentals as the digital curation lifecycle, and demonstrates how they should be put into effect. It introduces the XML language and the key standards for each type of metadata, including Dublin Core and MODS for descriptive metadata and PREMIS for its administrative and preservation counterpart. Finally, the book shows how these can all be integrated using the packaging standard METS. Two case studies from the Warburg Institute in London show how the strategy can be implemented in a working environment.<br><br>The strategy laid out in this book will ensure that a digital library's metadata will support all of its operations, be fully interoperable with others and enable its long-term preservation. It assumes no prior knowledge of metadata, XML or any of the standards that it covers. It provides both an introduction to best practices in digital library metadata and a manual for their practical implementation.

In Vitro Proliferation and Long-Term Preservation of Functional Primary Rat Hepatocytes in Cell Fibers

Primary hepatocytes are essential cellular resource for drug screening and medical transplantation. Since culture systems for them have already succeeded in reconstituting the biomimetic microenvironment, acquiring additional capabilities both to expand primary hepatocytes and to handle them easily would be expected as progress to the next stage. This paper describes a culture system for primary rat hepatocytes that is equipped with scalability and handleability relying on cell fiber technology. Cell fibers are cell-laden core-shell hydrogel microfibers; in the core regions, cells are embedded in extracellular matrix proteins, cultured three-dimensionally, and exposed to soluble growth factors in the culture medium through the hydrogel shells. By encapsulating primary rat hepatocytes within cell fibers, we first demonstrated they increase in number while keeping their viability and their hepatic specific functions for up to thirty days of subsequent culture. Then, we demonstrated the potency of the primary rat hepatocytes that proliferate in cell fibers not only as cell-based sensors to detect drugs that damage hepatic functions and hepatocellular processes but also as transplants to improve the plasma albumin concentrations of congenital analbuminemia. Therefore, our culture system could serve for innovating strategies and promising developments in applying primary hepatocytes to both pharmaceutical and medical fields.

In Vitro Proliferation and Long-Term Preservation of Functional Primary Rat Hepatocytes in Cell Fibers

Primary hepatocytes are essential cellular resource for drug screening and medical transplantation. Since culture systems for them have already succeeded in reconstituting the biomimetic microenvironment, acquiring additional capabilities both to expand primary hepatocytes and to handle them easily would be expected as progress to the next stage. This paper describes a culture system for primary rat hepatocytes that is equipped with scalability and handleability relying on cell fiber technology. Cell fibers are cell-laden core-shell hydrogel microfibers; in the core regions, cells are embedded in extracellular matrix proteins, cultured three-dimensionally, and exposed to soluble growth factors in the culture medium through the hydrogel shells. By encapsulating primary rat hepatocytes within cell fibers, we first demonstrated they increase in number while keeping their viability and their hepatic specific functions for up to thirty days of subsequent culture. Then, we demonstrated the potency of the primary rat hepatocytes that proliferate in cell fibers not only as cell-based sensors to detect drugs that damage hepatic functions and hepatocellular processes but also as transplants to improve the plasma albumin concentrations of congenital analbuminemia. Therefore, our culture system could serve for innovating strategies and promising developments in applying primary hepatocytes to both pharmaceutical and medical fields.