Features of the restoration of Buddhist thangka

Цель статьи — познакомить реставраторов и исследователей с традиционными и современными методами реставрации буддийской живописи на холсте, c оборудованием и материалами, которые применяются в лаборатории научной реставрации восточной живописи Государственного Эрмитажа. Актуальность данной работы продиктована развитием реставрационной практики буддийской живописи в последние десятилетия. В исследовании показано, как появление новых высокотехнологичных материалов, оборудования и методов исследования памятников позволяет реставратору более эффективно работать с ними. Также в данной работе показаны результаты изучения и исследования двух тангка. Комплексное исследование тангка, проведенное силами специалистов научно-исследовательских лабораторий, позволило правильно выбрать методики реставрации. Кроме этого, в работе приводятся краткие исторические сведения об иконографии и технологии создания тангка. В статье проводится анализ реставрационных методик и их выбора, рассматриваются этические проблемы, связанные с допустимой степенью вмешательства в структуру памятника. На примере сравнения подходов к реставрации двух буддийских тангка, реставрированных в разные годы (тангка «Образ буддийский Дорджэ Лэкпа» в 2018 году и тангка «Махакала синий шестирукий, трехглазый, стоящий на слоне с человеческой фигурой» в 2021 году), описаны различные методики. Анализ проведенных реставрационных мероприятий включает в себя описание проведенных исследований памятников до реставрации и методов отчистки поверхности, укрепления красочного слоя, восполнения грунта, выравнивания основы и восполнения утрат красочного слоя. В статье показана практическая значимость и результативность применения различных материалов, оборудования и методов реставрации буддийской живописи. Обобщены результаты реставрации обоих памятников. The aim of the article is to acquaint restorers and researchers of Buddhist painting on canvas with traditional restoration methods combined with modern equipment and materials that are used in the Laboratory of Scientific Restoration of Oriental Painting of the State Hermitage Museum. The relevance of this work is dictated by the development restoration practice of Buddhist painting in recent decades. It is shown in the study how the emergence of new high-tech materials, equipment and methods of studying monuments allows the restorer to work with them more effectively. Also in this paper, the results of the study and study of two thangkas are shown. Comprehensive the thangka study conducted by the specialists of research laboratories made it possible to choose the right restoration techniques. In addition, a brief work of historical information about the iconography and technology of creating a thangka is provided. The restoration techniques and their choices are analyzed in the article. Also the ethical problems related to the permissible degree of interference in the structure of the monument are examined. Using the example of comparing approaches to the restoration of two Buddhist thangkas restored in different years: the “Dorje Lakpa Buddhist Image” thangka in 2018, and the “Mahakala blue, 6-handed, 3-eyed, standing on an elephant with a human figure” thangka in 2021, various techniques are described. The analysis of the restoration measures carried out includes a description of the studies carried out on the monuments before the restoration, and methods of cleaning the surface, strengthening the paint layer, replenishing the soil, leveling the base and replenishing the losses of the paint layer. The article shows the practical significance and effectiveness of the use of various materials, equipment and methods of restoration of Buddhist painting. In conclusion, the results of the restoration of both monuments are summarized.

Evaluating direct and strategic placement of dredged material for marsh restoration through model simulations

Dredged material can be used for marsh restoration by depositing it on the marsh surface (thin-layer placement), by releasing it at the mouth of channels and allowing tidal currents to transport it onto the marsh platform (channel seeding), or by creating new marshes over shallow areas of open water. We investigate the efficacy of these different methods using a comprehensive 2D marsh evolution model that simulates tidal dynamics, vegetation processes, bank and wave erosion, and ponding. Total marsh area is assessed over 50 years in an idealized microtidal marsh under different relative sea level rise (RSLR) scenarios. For a given volume of total sediment added, the frequency of deposition is relatively unimportant in maximizing total marsh area, but the spatial allocation of the dredged material is crucial. For a given volume of sediment, thin-layer deposition is most effective at preserving total marsh area, especially at high rates of RSLR. Channel seeding is less efficient, but it could still provide benefits if larger amounts of sediment are deposited every 1-2 years. Marsh creation is also beneficial, because it not only increases the marsh area, but additionally slows the erosion of the existing marsh. The 2D model is highly computationally efficient and thus suited to explore many scenarios when evaluating a restoration project. Coupling the model with a cost assessment of the different restoration techniques would provide a tool to optimize marsh restoration.

Image Restoration using Recent Techniques: A Survey

Image Restoration is one of the challenging and essential milestones in the image processing domain. Digital image processing is a technique for manipulating digital images using a variety of computer algorithms. The process of transforming the degraded or damaged image to the original image can be known as Image Restoration. The image restoration process improves image quality by converting the degraded image into the original clean image. The techniques for image restoration are comprised of predefined parameters through which digital image gets processed for refinements. The purpose of restoration is to start with the acquired image and then estimate the original image as accurately as possible. A degraded image can be contaminated by any of a blur or noise or both. Many factors can contribute to image degradation, including poor capture, poor lighting, and poor eyesight. Medical science, defensive sensor systems, forensic detections, and astrology all rely on image restoration for accuracy. This paper discusses various image restoration techniques using recent trends for performance improvements.

In Vitro Study on the Adhesive Performance of Some Resin-Based Materials Used to Restore Class II Cavities

The study aimed to evaluate the adhesive performances of two ormocer materials and two micro-hybrid composites placed to restore class II cavities. We tested the null hypothesis, which considered that the adhesive behaviors of tested materials did not differ. On each extracted tooth, two class II cavities were prepared having an enamel located cervical margin and a cementum located cervical margin, respectively, and were restored using two different restoration techniques. The teeth followed a tooth impregnating protocol and were sectioned and evaluated by optical microscopy to highlight the marginal microleakage around restorations. Cervical and occlusal microleakage as well as microleakage ratios were calculated. The microleakage test showed that all tested materials exhibited some degree of dentinal microleakage both on cervical and occlusal areas irrespective of the restoration technique. Some significant differences were recorded in adhesion performance of the materials. The cervical microleakage ratio was significantly increased for one of the micro-hybrid resin composites in comparison with one of the ormocer materials (p = 0.0159). Significantly differences were observed in occlusal microleakage ratios when the two micro-hybrid composites were compared (p = 0.047). The results failed to reject the null hypothesis. The present study could not demonstrate the superiority of ormocer-materials relative to conventional composites.

Restoration techniques of fractured endodontically treated teeth

This literature review aims to discuss and collect evidence about restoration techniques of fractured endodontically treated teeth. According to studies in the literature, root canal treatment and restoration of endodontically treated teeth have been reported as two separate clinical procedures although many aspects of both procedures are similar. Conducting restoration procedures following endodontic treatment has been reported to be so important as the first obturation of the root canal, and it has been reported with many advantages and favorable events, including eradication and minimizing the presence of bacteria and microorganisms, which might induce serious complications to the affected teeth. Additionally, the literature review discusses the technique of interim restorations, which has been reported to have favorable advantages and outcomes. However, it should be noted that the process is temporary and definitive restorations must be conducted later on. Also, this research investigates the different substances that should be used with the modality, and the different approaches that were previously reported to restore mature and immature affected teeth. Finally, evidence shows that amalgam-based restorations are becoming inferior to resin composite-based restorations which are also more superior to the stainless-steel crown-based ones. Unifying the guidelines for clinical practice is encouraged to obtain favorable outcomes. All the detailed techniques are presented and fully discussed within the main text of this research.