955 resultados para Preservation of latex


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The body of work presented in this thesis are in three main parts: [1] the effect of ultrasound on freezing events of ionic systems, [2] the importance of formulation osmolality in freeze drying, and [3] a novel system for increasing primary freeze drying rate. Chapter 4 briefly presents the work on method optimisation, which is still very much in its infancy. Aspects of freezing such as nucleation and ice crystal growth are strongly related with ice crystal morphology; however, the ice nucleation process typically occurs in a random, non-deterministic and spontaneous manner. In view of this, ultrasound, an emerging application in pharmaceutical sciences, has been applied to aid in the acceleration of nucleation and shorten the freezing process. The research presented in this thesis aimed to study the effect of sonication on nucleation events in ionic solutions, and more importantly how sonication impacts on the freezing process. This work confirmed that nucleation does occur in a random manner. It also showed that ultrasonication aids acceleration of the ice nucleation process and increases the freezing rate of a solution. Cryopreservation of animal sperm is an important aspect of breeding in animal science especially for endangered species. In order for sperm cryopreservation to be successful, cryoprotectants as well as semen extenders are used. One of the factors allowing semen preservation media to be optimum is the osmolality of the semen extenders used. Although preservation of animal sperm has no relation with freeze drying of pharmaceuticals, it was used in this thesis to make a case for considering the osmolality of a formulation (prepared for freeze drying) as a factor for conferring protein protection against the stresses of freeze drying. The osmolalities of some common solutes (mostly sugars) used in freeze drying were determined (molal concentration from 0.1m to 1.2m). Preliminary investigation on the osmolality and osmotic coefficients of common solutes were carried out. It was observed that the osmotic coefficient trend for the sugars analysed could be grouped based on the types of sugar they are. The trends observed show the need for further studies to be carried out with osmolality and to determine how it may be of importance to protein or API protection during freeze drying processes. Primary drying is usually the longest part of the freeze drying process, and primary drying times lasting days or even weeks are not uncommon; however, longer primary drying times lead to longer freeze drying cycles, and consequently increased production costs. Much work has been done previously by others using different processes (such as annealing) in order to improve primary drying times; however, these do not come without drawbacks. A novel system involving the formation of a frozen vial system which results in the creation of a void between the formulation and the inside wall of a vial has been devised to increase the primary freeze drying rate of formulations without product damage. Although the work is not nearly complete, it has been shown that it is possible to improve and increase the primary drying rate of formulations without making any modifications to existing formulations, changing storage vials, or increasing the surface area of freeze dryer shelves.

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* The part of this article presenting institutional involvement is an extended and updated version of the respective part of a report on Bulgaria prepared by Milena Dobreva for a MINERVAPlus Global Report (Coordinating digitisation in Europe. Progress report of the National Representatives Group: coordination mechanisms for digitisation policies and programmes 2004, forthcoming).

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ACM Computing Classification System (1998): J.2.

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This paper presents a survey of the existing services provided by the digital libraries and repositories on mathematics of the content provider partners in the EuDML project. The purpose is to support the development of the concepts, criteria and methods for the continuous evaluation of these and new relevant existing services. The work was concentrated on the classification of the relevant services in order to specify a common evaluating structure.

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We present the Hungarian National Scientific Bibliography project: the MTMT. We argue that presently available commercial systems cannot be used as a comprehensive national bibliometric tool. The new database was created from existing databases of the Hungarian Academy of Sciences, but expected to be re-engineered in the future. The data curation model includes harvesting, the work of expert bibliographers and author feedback. MTMT will work together with the other services in the web of scientific information, using standard protocols and formats, and act as a hub. It will present the scientific output of Hungary together with the repositories containing the full text, wherever available. The database will be open, but not freely harvestable, and only for non-commercial use.

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In an attempt to answer the need of wider accessibility and popularization of the treasury of Bulgarian folklore, a team from the Institute of Mathematics and Informatics at the Bulgarian Academy of Sciences has planned to develop the Bulgarian folklore artery within the national project ―Knowledge Technologies for Creation of Digital Presentation and Significant Repositories of Folklore Heritage‖. This paper presents the process of business modeling of the application architecture of the Bulgarian folklore artery, which aids requirements analysis, application design and its software implementation. The folklore domain process model is made in the context of the target social applications—e-learning, virtual expositions of folklore artifacts, research, news, cultural/ethno-tourism, etc. The basic processes are analyzed and modeled and some inferences are made for the use cases and requirements specification of the Bulgarian folklore artery application. As a conclusion the application architecture of the Bulgarian folklore artery is presented.

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The report presents a description of the most popular digital folklore archives in the world. Specifications for designing and developing web-based social-oriented applications in the field of education and cultural tourism are formulated on the basis of comparative analysis. A project for structuring and categorizing the content is presented. A website for accessing the digital folklore archive is designed and implemented.

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Experimental researches of one of the eldest bells («Mazepa»-see Appendix1) in Ukraine, are considered in the article. The spectra and spectra- time analysis of bell ringing is embodied, main frequencies of oscillation and musical intervals of sounding are determined. Comparative description of bell sounding with the known bells of Russia and Bulgaria is given.

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It is shown, that in the process of evolution, a relationship between some hidden parameters of acoustic signals and expected emotional response to them has been formed. This relationship is a necessary condition for a living creature to survive. The efficiency of the concept represented is illustrated using examples from the field of classical music, ethnic African music, as well as biolinguistic signals of animals. Reasons of a particular impact of bell rings are analyzed using acoustic signals of some Bulgarian and Russian bell rings and chimes.

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The aim was to develop an archive containing detailed description of church bells. As an object of cultural heritage the bell has general properties such as geometric dimensions, weight, sound of each of the bells, the pitch of the tone as well as acoustical diagrams obtained using contemporary equipment. The audio, photo and video archive is developed by using advanced technologies for analysis, reservation and data protection.

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We investigate digitalization and security of the Bulgarian and Indian cultural artifacts in multimedia archive. In the paper we describe project implementation and methods for intellectual property protection that are result of bilateral cultural and scientific cooperation between research-workers in India and Bulgaria.

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This paper presents the main concepts of a project under development concerning the analysis process of a scene containing a large number of objects, represented as unstructured point clouds. To achieve what we called the "optimal scene interpretation" (the shortest scene description satisfying the MDL principle) we follow an approach for managing 3-D objects based on a semantic framework based on ontologies for adding and sharing conceptual knowledge about spatial objects.

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This article briefly reviews multilingual language resources for Bulgarian, developed in the frame of some international projects: the first-ever annotated Bulgarian MTE digital lexical resources, Bulgarian-Polish corpus, Bulgarian-Slovak parallel and aligned corpus, and Bulgarian-Polish-Lithuanian corpus. These resources are valuable multilingual dataset for language engineering research and development for Bulgarian language. The multilingual corpora are large repositories of language data with an important role in preserving and supporting the world's cultural heritage, because the natural language is an outstanding part of the human cultural values and collective memory, and a bridge between cultures.

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Paper deals with the current issues and challenges before digitization of literary heritage in the Bulgarian libraries. Main problems are outlined. Socialization of digitized heritage is commented.

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The aim of this paper is to review the sound archives of the Bulgarian National Radio (BNR). The accesses to different sound archives are analyzed. A case study for preparing a radio presentation using the existing archives is outline.