Long-term Preservation Research Articles

An overview of Synlab SDN Biobank’s quality control system

Biobanks are valuable service units that ensure the usage of high-quality biological samples. They contribute to translational research, and their support may improve future therapeutic approaches. They store biological samples that can be used to examine circulation biomarkers, immune cells, and immunohistochemistry aspects of illnesses and further in-depth examinations using NGS techniques. The IRCCS Synlab SDN Biobank has about 70,000 well-preserved cryopreserved human samples from various diseases, primarily oncological but also neurological and cardiovascular. These biospecimens were taken from 25,000 participants underwent imaging with a contrast agent. The goal is to propose quality control assays that meet the requirements of the international standard ISO 9001:2015 and ISO 20387:2020 accreditation. PBMCs viability was determined, and immune subset cells were analyzed by flow cytometry. Furthermore, the expression of ubiquitous miRNAs was used to assess plasma sample integrity. The quality controls demonstrated that the biological samples were correctly cryopreserved; the preservation of human biological samples did not affect the quality of the biological samples tested. Indeed, the cryopreserved PBMCs had a vitality of more than 80%, and the lymphocyte subsets could be selected for future immune cell investigations. Furthermore, miRNA expression was highest in thawed plasma samples compared to the positive and negative controls. We evaluated the quality of our randomly selected biobank-thawed human samples. Both PBMCs and plasma samples fulfill the high-quality standards needed for biomedical research, assuring their long-term preservation. However, further research is needed in the biobanking field to establish globally accepted procedures to confirm the quality of biological samples.

Modified SiO2@cinnamaldehyde/nanocellulose coating film for loquat preservation

Although cinnamaldehyde (CA) is an excellent antimicrobial agent, its application in the food industry was limited by its volatility and lack of antimicrobial persistence. Herein, aminated hollow mesoporous silica (NH2-HMSN) was prepared by selective etching and amino-modified. Subsequently, long-acting antibacterials with regulated release (NH2-HMSN@CA) were obtained by using NH2-HMSN as cinnamaldehyde carrier. NH2-HMSN@CA can effectively regulate the release of CA, and has 100 % inhibition effect on the growth of E. coli, S. aureus and C. acutatum. In addition, nanocellulose/NH2-HMSN@CA (CHA) coating film was prepared for postharvest preservation of loquat. The coating film effectively improved the storage quality and shelf life of loquat, and delayed the postharvest decay of loquat. The prepared coating film active packaging for long-term preservation is expected to provide a scheme for promoting sustainable preservation of postharvest loquat.

Quantitative and qualitative assessment of airborne microorganisms during gross anatomical class and the bacterial and fungal load on formalin-embalmed corpses

Mold growth on body donations remains an underreported yet serious issue in anatomical teaching. Bacterial and fungal growth pose health risks to lecturers and students, alongside with ethical and aesthetic concerns. However, limited information exists on the presence of bacteria and fungi on body donations and their underlying causes. To investigate the potential impact of airborne germs on body donation contamination, we conducted indoor air measurements before, during, and after our anatomical dissection course, with outdoor measurements serving as a control. Tissue samples from the dissected body donations were collected to assess the germ load, with qualitative and quantitative microbiological analyses. Air samples from the dissection hall contained no fungi, but various fungal species were identified in the adjacent stairways and outdoors which implies that fungal occurrence in the dissection hall air was independent of lecturers’ and students’ presence. Moreover, our results indicate that adequate ventilation filters can effectively reduce indoor fungal germs during courses, while the bacterial load in room air appears to increase, likely due to the presence of lecturers and students. Additionally, the tissue samples revealed no bacterial or fungal germs which implies that our ethanol-formalin-based embalming solution demonstrates an effective long-term antimicrobial preservation of corpses.

Enhancement of the hygrothermal ageing properties of gelatine films by ethylene glycol diglycidyl ether

Owing to the instability of gelatine in hygrothermal environments, gelatine-based cultural heritage undergo various deterioration processes, such as cracking, peeling, warping, curling and fracture, posing significant threats to its long-term preservation. Building on previous research, this study investigates the stability of polyol glycidyl ether–gelatine composite films under high-humidity and high-temperature conditions using ethylene glycol diglycidyl ether (EGDE) as a model compound. The hygrothermal ageing properties of EGDE–gelatine composite films are evaluated in terms of macrosize, mesoscopic structure, surface properties and mechanical properties. Results indicate that EGDE enhances the dimensional stability and swelling ratios of the composite films, stabilizes the pore structure and distribution and maintains the hydrophilicity and molecular structural stability under hygrothermal ageing conditions. Furthermore, the incorporation of EGDE leads to superior stress–strain properties of the composite films in such challenging environments. This study provides valuable experimental data for the preparation and conservation applications of gelatine-based cultural heritage materials.

The color influence of dust in air pollutants on architectural painting: a case of archery tower at the West Gate in Shaanxi, China

At present, under the influence of environmental pollution, the color of architectural painting gradually darkens, loses luster, and even cracks when the pigment falls off, which seriously affects the long-term preservation of architectural painting. In order to study the damage mechanism of dust particles to the color of the architectural painting, this study took the archery tower at the West Gate as the research object, monitored the temperature and humidity of the indoor environment, and analyzed the composition of the dust by ICP-MS, IC, and XRD. The experimental results showed notable fluctuations in the indoor humidity in inner the archery tower at the West Gate during the monitoring period from January to March, which were not conducive to the preservation of wood-colored paintings. The 24-h average PM2.5 and PM10 concentrations, measured over 2 days in January, were beyond the National Ambient Air Quality Standard norms, and PM contains a large amount of soluble salts such as sulfate and nitrate, causing serious salt erosion and damage to the color painting layer. Through the simulation experiment of the color painting layer, it was revealed that the dust particles deposited on the surface of the color painting layer change the spectral characteristics of the color painting layer, and then cause the color layer to lose its original hue, fade become blurred, or darken. It was anticipated that this research would serve as a valuable reference for the preventive protection of the color painting layer of the archery tower at West Gate.

Effect of Oscillating Magnetic Fields (OMFs) and Pulsed Electric Fields (PEFs) on Supercooling Preservation of Atlantic Salmon (Salmo salar L.) Fillets.

Salmon, rich in protein and omega-3 fatty acids, has a short shelf life of 1 to 3 days when stored at 2 to 8 °C. Freezing, used for long-term preservation, often results in ice crystal formation. Ice crystals can cause structural damage, leading to cell wall rupture, which can affect the texture and cause nutrient loss. Ultimately, this process reduces the overall quality of the salmon. Supercooling, which cools food below its freezing temperature without forming ice crystals, offers an alternative. This study investigated the effects of oscillating magnetic fields (OMFs) and pulsed electric fields (PEFs) on ice crystal formation during salmon supercooling. The results showed that using OMFs and PEFs in supercooling reduced the storage temperature of salmon, maintaining a similar thiobarbituric acid reactive substances (TBARS) value to that of frozen and refrigerated samples. There was no significant difference in meat color between the fresh and frozen samples, and drip loss weight was comparable between the fresh and supercooled samples. The microbiological counts were the lowest in the supercooled samples compared to the frozen and refrigerated ones. These findings suggest that supercooling storage with OMFs and PEFs can mitigate quality degradation in salmon typically associated with freezing.

Scientific analysis of folk contract documents from Tianshui region: insights of fiber use and preservation state

Folk contract documents (FCD) are valuable materials for studying social history, and the paper they use reflects the social realities of different eras and social classes. Research and scientific analysis of numerous FCD samples after the fourteenth century are rare. We conducted a study on 96 Tianshui folk contract documents (TFCD, 107 paper samples) from the Tianshui area of Gansu Province, Northwest China, taking into account both the textual content and the materiality of paper carriers, and interpreted the results from multiple lines of evidence and discussion. Physical performance analysis revealed that the paper used by the northern folk exhibits a lower apparent density, which is not conducive to the long-term preservation of paper. The preservation status investigation, curtain pattern analysis, and fiber analysis show that the paper used in the TFCD differs from traditional cultural paper regarding disease types, production precision, and fiber materials, providing a basis for its protection and restoration. The analysis of chemical components indicated that the aging and yellowing of paper can be correlated with the content of sulfur and carbonyl groups. The feasibility of using pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) analysis to quickly identify papermaking fibers in a large number of paper samples was proposed. By utilizing various techniques to inspect the paper of documents, this study helps to enhance the academic understanding of FCD materials. In addition, it expands the knowledge base of Northwest handmade paper.

Environmental analogs from yellowstone hot springs on geochemical and microbial diversity with implications for the search for life on Mars

From Viking landers to Perseverance rover, Mars has been explored by several in situ missions capable of analyzing organic compounds. Results from the SAM and SHERLOC on Curiosity and Perseverance, respectively, support the detection of lean organic matter (at ppb-ppm levels) in the top surface samples, although the source(s) and preservation mechanisms are still ambiguous. Perseverance is currently exploring a fluvio-lacustrine system at Jezero crater and may explore an ancient volcanic terrain after exiting the crater. As Perseverance would collect samples for potential return to Earth, preparation is needed for sample return efforts through various means including i) the detection of trace organic compounds in various matrices, ii) validation of compounds identified by Martian rovers, and iii) better understanding of mechanisms of their production on Mars. On these returned samples, the community may be able to resolve the timing of organic matter formation and refine hypotheses regarding organic preservation in Martian soils despite the presence of numerous oxidants, salts, and pH-temperature intra and inter-site variations that are less conductive to long-term preservation of organic matter. For instance, acidic conditions promote clay catalyzed isomerization, but seem to benefit for the fatty acid preservation producing organic-salts or favoring salt dissolution in the matrix to protect organic compounds from radiations and water alteration. With a similar aim, we selected samples from Yellowstone National Park hot springs and silica sinters as analogs to locations visited by Curiosity and Perseverance or – in the future – Rosalind Franklin rover. The hot springs in this study developed over hundreds to thousands of years, providing optimal conditions (i.e., matrix composition, temperature, pH) of preservation for organic molecules, extremophilic and mesophilic cells. In our study, the most well preserved organic matter and biosignatures were detected in acidic silica sinters with a surface (water) temperature below 50 °C and a minor crystalline phase. The gas chromatography – mass spectrometry molecular analysis revealed a variety of organic compounds we classified as bioindicators (such as amino acids, nucleobases, and sugars), and biosignatures (such as long-chain branched and/or (poly)unsaturated lipids, secondary metabolites involved in the quorum sensing or communication between individuals). We validated with a SAM/MOMA-like benchtop extracting oven the organic matter extraction protocols performed with the SAM experiment. We identified using the different SAM and MOMA extraction protocols (pyrolysis and wet-chemistry derivatizations) eight microbial classes through a unique untargeted environmental metabolomics’ method embracing space flight technology constraints. Additionally, we identified one (and likely two) agnostic biosignature(s): i) the concomitance of some elements and organic compounds in the analogs (correlation of organic matter elements: C, N, S, P and organic molecules co-located with essential biological elements: Fe, Mg, V, Mn and non-essential biological elements concentrated by microorganisms: As, Cs, Ga), and ii) the negative isotope C and N ratio demonstrating organic molecules rich in 12C and 14N: archaeal, bacterial, and eukaryotic lipids for an efficient low energy-consuming metabolism.

Constructing risk in trustworthy digital repositories

PurposeThis article investigates the construction of risk within trustworthy digital repository audits. It contends that risk is a social construct, and social factors influence how stakeholders in digital preservation processes comprehend and react to risk.Design/methodology/approachThis research employs a qualitative research design involving in-depth semi-structured interviews with stakeholders in the Trustworthy Digital Repository Audit and Certification (TRAC) process, and document analysis of the TRAC checklist and audit reports. I apply an analytic framework based on the Model for the Social Construction of Risk in Digital Preservation to this data.FindingsThe findings validate the argument that risk in digital preservation is indeed socially constructed and demonstrate that the eight factors in the Model for the Social Construction of Risk in Digital Preservation do indeed influence how stakeholders constructed their understanding of risk. Of the eight factors in the model, communication, expertise, uncertainty and vulnerability were found to be the most influential in the construction of risk during the TRAC audit process. The influence of complexity, organizations political culture, were more limited.Originality/valueThis article brings new insights to digital preservation by demonstrating the importance of understanding risk as a social construct. I argue that risk identification and/or assessment is only the first step in the long-term preservation of digital information and show that perceptions of risk in digital preservation are shaped by social factors by applying theories of social construction and risk perception to an analysis of the TRAC process.

Seasonal seminal quality variations and vitrification prospects in black flounder Paralichthys orbignyanus

Long-term preservation of gametes has been identified as a tool to improve broodstock management and increase the number of juveniles produced by artificial fertilization. Paralichthys orbignyanus is an important commercial and recreational species distributed in marine and estuarine waters from Rio de Janeiro (Brazil) to the San Matías Gulf (Argentina). This work focused on studying the seminal quality of tank-reared P. orbignyanus, demonstrating that males are fluent year-round, with the highest yields at the early reproductive season. Fresh sperm exhibited good forward swimming, and samples could be refrigerated up to 48 h while retaining their motility after activation. The optimal conditions for P. orbignyanus sperm motility activation were established as 950 mOsmol/Kg and pH values between 7 and 7.9. Additionally, a well-defined protocol for semen vitrification was developed to assess the cryotolerance of this species’ sperm. We successfully produced high-quality sperm samples, using two vitrification formulations containing trehalose and both z-1000 and x-1000 polymers, that can be used in a near-future in vitro embryo production program.

Evaluating pasture cover density mapping: a comparative analysis of Sentinel-2 and Spot-5 multispectral sensor images

Vegetation density extraction is influenced by the characteristics of satellite images, vegetation type, classification algorithm, and region, but there is little information about multispectral imaging (MSI). Studying the compatibility of the information content of sensors to replace sensors in areas where there is no easy access to their data is necessary for remote sensing (RS) studies. This study aims to assess the suitability of MSI from Sentinel-2 and Spot-5 satellites for generating pasture density maps. The Middle Kashkan watershed in the Lorestan Province of Iran was the study area. Geometric correction of the images was performed using ground control points (GCP) and the area's digital elevation model, achieving an accuracy of 0.21 pixels or better. Supervised classification techniques including parallelogram, minimal distance, maximum likelihood, and artificial neural network (ANN) algorithms were applied to the primary MSI of each satellite, as well as the integrated image of Spot-5 and the resulting pasture density map. Three density categories were considered: 5–25%, 25–50%, and over 50%. To validate the accuracy of the classification, a ground truth map of the region was created by interpreting a referenced official digital orthophotomosaic image at a scale of 1:40,000. Comparative analysis of the classified images revealed that the Sentinel-2 image with PCA-2-8 band composition and ANN classification algorithm yielded superior results, with an overall accuracy of 65.72% and a kappa coefficient of 0.08, compared to the Spot-5 image with PCA-3-1 band composition and the ANN classification algorithm. Spot-5 satellite images demonstrated greater effectiveness in generating pasture cover maps across the three density categories. These findings suggest that satellite images with suitable spatial and spectral resolution can be effectively utilized for generating accurate pasture density maps and monitoring long-term pasture preservation, particularly in regions characterized by high aerial photography altitudes in pasture areas. This approach holds the potential for effective pasture management and conservation efforts on a global scale.

Semantic Web Insights Into the Classification of Folk Paper-Cut Cultural Genes

This study aims to classify folk paper-cut patterns by regional culture, leveraging Semantic Web and LSTM technologies to discern how these patterns reflect distinct cultural characteristics. By developing an LSTM model capable of recognizing and categorizing these patterns, our study not only demonstrates high accuracy in classifying regional cultural genes but also reveals the depth of cultural heritage embedded in paper-cut art. The findings underscore the potential of computational methods in understanding and preserving the rich tapestry of cultural expressions through paper cuts. This work sets a foundation for future explorations into the digital preservation of cultural heritage, highlighting the critical role of technology in safeguarding and interpreting traditional arts in the context of regional culture.

Enhancing frozen chicken meat quality by isochoric storage as compared with conventional frozen storage

Isochoric freezing is an emerging technique for preserving food at subfreezing temperatures under moderately high pressure. This study investigated the impact of isochoric frozen storage (IFS) of chicken breast for 0, 3, 6, 9, 12, and 15 days using 2.5% NaCl solution at −4 °C on qualities including physicochemical and microbial attributes, as compared with samples under conventional frozen storage (CFS) at the same temperature. Results showed IFS samples exhibited slight enhancements in various quality parameters, including pH, protein solubility, TBARS, drip loss, shear force, yellowness, cooking loss, and a slow decreasing rate in lightness, redness, Ca2+-ATPase activity, total viable count, and TVB-N, while substantial changes occurred in CFS samples for all quality parameters. This suggests that the impact of high pressure in isochoric freezing would be advantageous in terms of microbial destruction and enzymatic inhibition, potentially offering better long-term preservation techniques for the industry.

Dynamically documenting archaeological excavations based on 3D modeling: a case study of the excavation of the #3 fossil of hominin cranium from Yunxian, Hubei, China

Documenting tangible cultural heritage using 3D modeling techniques is gradually becoming an indispensable component of archaeological practice. The 3D modeling techniques based on photogrammetry and LiDAR scanning enable high-accuracy and high-realistic reconstruction of archaeological sites, and have been proven a powerful tool for documenting archaeological excavations. However, dynamically documenting an ongoing excavation using these techniques is still considered tedious, time-consuming, expensive, and dependent on expertise. Moreover, the application of 3D modeling techniques in archaeological excavations still faces some technical challenges, such as modeling with multi-source and multi-scale data, fusing local models at different times into a whole, achieving fast modeling while GPU workstations are not available in the field, and evaluating the quality of 3D models. As a result, there are still very few archaeological teams deeply engaged in dynamic documentation with 3D modeling techniques, and traditional drawing sketches and taking photographs still dominate. In these senses, documenting the archaeological excavation at the Yunxian Man site (located in Hubei, China) is an invaluable opportunity for exploration and practice. Archaeologists determined to conduct dynamically documenting at the beginning of the 6th excavation project for the site, and established a rotation system to reconcile physical excavation with digital preservation. Through repeated practice and communication, we proposed a workflow and pursued several new methods to enhance the feasibility of dynamically documenting, and obtained 4D models of the ongoing archaeological excavations. In 2022, the Yunxian Man site unearthed the most intact fossil of hominin cranium from about one million years ago in the Eurasian continent, preserving important and scarce anatomical features of early humans in Asia. As the original taphonomic context of the fossil corroded away during physical excavations, the digital documentation consisting of 4D models serves as permanent original data source in subsequent archaeological research. Moreover, we obtained cross-scale 3D models from geographical environment to archaeological site, excavation area, and cultural remains, and all of these 3D models are in an actual, unified coordinate framework. Thus, we can contribute to multidisciplinary cross-collaborative research through data sharing. Considering that digital documentations serve a great value in archaeological research, this paper focuses on sharing the workflow and methods to facilitate digital preservation for more archaeological projects.

Inactivation of murine norovirus and hepatitis A virus on various frozen fruits using pulsed light

The frozen fruit sector has experienced significant growth due to improved product quality as well as the advantage of long-term preservation. However, freezing alone does not eliminate foodborne viruses, a major public health concern and considerable economic burden. One promising disinfecting treatment is pulsed light, shown previously to inactivate hepatitis A virus (HAV) and murine norovirus-1 (MNV-1) on the surface of fresh berries. Viral loads were reduced by 1–2 log, with minor visual quality deterioration observed. In this study, an FDA-compliant pulsed light treatment (11.52 J/cm2) was applied to frozen fruits and berries. Infectious MNV-1 and HAV titers were reduced by 1–2 log on most frozen fruits. A noteworthy finding was that reductions of both viruses on cranberries exceeded 3.5 log cycles. Although pulsed light caused a measurable rise in temperature on the product surface, no visible physical changes (e.g., color) were observed, and the fruit pieces were still frozen after treatment. Although the reduction of infectious titer by pulsed light alone was not large (1–2 log), considering the low amount of virus typically found on fruit, it may be beneficial in the frozen fruit sector. It would be easy to combine with other treatments, and synergic interactions might increase virus inactivation.

Digital Preservation, Inheritance, and Innovative Development of Intangible Cultural Heritage from the Perspective of Metaverse

With the rapid change of meta-universe technology, the digital inheritance of intangible cultural heritage ( ICH ) shows unprecedented broad prospects, and injects new vitality into the inheritance and development of ICH. Aiming at the multiple challenges in the process of digital inheritance of ICH, this paper explores in depth the specific application of meta-universe technology in ICH, and proposes a series of innovative strategies such as the digital inheritance of visual language, the construction of immersive experience, the protection of free creation and copyright, and the construction of panoramic interactive venues. These strategies provide a new perspective and practical methodology for the digital inheritance of intangible heritage, and at the same time make a positive contribution to the promotion of the continuous prosperity and innovation of intangible heritage culture. This paper is committed to providing solid theoretical support and practical guidance for the protection, inheritance and innovation of ICH, so as to help ICH culture to be revitalized in the digital era.

Digitization of logistics and supply chain management

The article presents theoretical and applied aspects of digitalization of logistics and supply chain management. It is emphasized that the processes of digitalization of supply chains and logistics are a modern requirement for increasing business efficiency, as well as solving environmental, social and management problems of successful companies. Digitization of supply chains and logistics is defined as the integration of digital technologies and the implementation of digital tools to optimize, automate and increase the efficiency of all stages of the logistics process. Key modern technologies in logistics and supply chains are examined, including artificial intelligence (AI), the Internet of Things (IoT) and Big Data. The role of AI in optimizing logistics processes, forecasting market behavior, inventory management and route planning is outlined. Emphasis is placed on the importance of IoT for tracking goods, monitoring storage conditions and vehicle maintenance. The role of Big Data in optimizing supply chains, improving decision-making and compliance with regulatory requirements is analyzed. The use of digital documentation and electronic document circulation are highlighted as important areas of digitization. The difference between digitization of documents and digitalization of document circulation is revealed: digitization, or digital preservation, refers to the transfer of information from paper documents to electronic format for convenient and safe storage of files and access to them in the future; digitalization involves the creation of documentation in computer applications, its intelligent processing and analysis, its accumulation in digital repositories, and the wide use of its data to solve various problems. It is noted that one of the main directions of digitization of documents is the automated reading of documents and data entry, which is implemented using specialized software for automatically extracting information from paper documents and entering it into digital systems. The list of the main logistics documents that are subject to digitization and the digitization of which leads to an increase in the efficiency of the supply chain (delivery confirmation, bill of lading, packing lists, invoices, cargo manifest, etc.) is provided. It was concluded that digitalization of logistics is a significant factor for modern companies seeking to increase their competitiveness in the market. It also enables the integration of all company divisions, improves product tracking, speeds up customs procedures, optimizes transport costs and increases the flexibility of return management. Despite the shortcomings that accompany this process, digitalization of logistics is necessary to achieve sustainable development and effective management of supply chains in today's world.

Degradation of handmade paper: Exploration of water adsorption behavior and estimation of lifespan based on time-temperature-humidity superposition

Traditional handmade papers, as the carriers of paper-based cultural relics, inevitably undergo various deteriorations during long-term preservation. Establishing a reasonable degradation kinetic model of handmade paper under the synergistic action of multiple factors is the crucial to evaluate paper aging and lifespan of paper. This study explores the moisture content and diffusion behavior of water molecules in traditional handmade paper to identify the interaction between fibers and water molecules at the accessible sites by two-dimensional infrared spectroscopy (2D-COS). Additionally, the optimized second-order kinetic models for the degradation of three types of Kaihua handmade papers was presented based on the time-temperature-humidity superposition method. A time-temperature-humidity translation factor is incorporated into the dynamic model to quantitatively analyze the synergistic effect of temperature and humidity on the degradation rate of handmade paper. The degradation rates of handmade paper with different raw materials and handcraft processes demonstrated significant effects of the cooking and bleaching processes on the aging degradation process and the durability of the paper. The improved second-order degradation kinetic model, considering the cooperation process with multi-factors and mechanisms, enables the extrapolation of paper aging properties at arbitrary temperature and humidity effectively, which provides a more reasonable estimation of handmade paper's lifespan.

In Vitro Propagation and Conservation of Lavandula stoechas subsp. luisieri and Pterospartum tridentatum, Two Important Medicinal and Aromatic Species from Portugal.

Lavandula stoechas subsp. luisieri and Pterospartum tridentatum are two valuable aromatic and medicinal plants. Their biometric and morphological parameters, such as the number of new shoots, length of the longest shoot, multiplication rate, and fresh weight, were evaluated using the multiplication MS medium protocol. The rooting protocols involved immersing the explants in IBA (1 g L-1) and a commercial IBA (3.3 g L-1) preparation (Clonex®). Slow-growth conservation assays were carried out using two different sucrose concentrations (15 g L-1 and 30 g L-1), and a control, with the cultures kept at 4 °C for 12 months. The multiplication rate for L. stoechas subsp. luisieri was 6.8, and that of P. tridentatum was 13.3, achieved using the MS medium supplemented with 0.2 mg L-1 BAP, 1 mg L-1 BAP, and 0.5 mg L-1 IBA. The application of Clonex® showed the best ex vitro rooting results in L. stoechas subsp. luisieri (77%) and P. tridentatum (90%). In the slow-growth conservation assays, at 4 °C, in darkness for 12 months, an excellent survival rate was achieved in L. stoechas subsp. luisieri (>80%) and P. tridentatum (>90%), even at the reduced sucrose concentration. This study demonstrates the effectiveness of in vitro multiplication and ex vitro rooting protocols for two valuable aromatic and medicinal plants. These findings are significant for the ex situ conservation of these species, as they provide effective long-term preservation and utilization strategies.

THE IMPORTANCE OF USING MODELING WHEN TEACHING CHEMISTRY IN SECONDARY SCHOOLS

There is a great interest of both teachers and students in the use of modeling in the process of teaching chemistry in a secondary school. The correct use of modeling in the educational process facilitates the work of the teacher and increases the interest of students in this subject. With the use of models, the visibility of lessons increases, multimedia systems stimulate the quality of work, activate all the senses of students, and due to the increase in the quality of education, conditions are created for the long-term preservation of acquired knowledge.