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5. Contributors

Author

Bell, Christian H., primary, Corvari, Vincent, additional, Gomes, Diana C., additional, Grapentin, Christoph, additional, Heitz, Marc, additional, Huang, Lihua, additional, Jahn, Michael, additional, Khan, Tarik A., additional, Koulov, Atanas V., additional, Mahler, Hanns-Christian, additional, Marine, Jeannette E., additional, Menon, Sreejit R., additional, Mueller, Claudia, additional, Pfaff, Janina, additional, Rao, V. Ashutosh, additional, Rumbelow, Stephen J., additional, Schöneich, Christian, additional, Schröter, Ariane, additional, and Singh, Satish K., additional

Published
2023
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8. Editorial: Smart Geography: 100 Years Bulgarian Geographical Society

Author

Nedkov, Stoyan, Koulov, Boian, Nikolova, Mariyana, Ilieva, Nadezhda, Zhelezov, Georgi, Naydenov, Kliment, Koutsopoulos, Kostis, Series Editor, Miguel González, Rafael de, Series Editor, Schmeinck, Daniela, Series Editor, Nedkov, Stoyan, editor, Zhelezov, Georgi, editor, Ilieva, Nadezhda, editor, Nikolova, Mariyana, editor, Koulov, Boian, editor, Naydenov, Kliment, editor, and Dimitrov, Steliyan, editor

Published
2020
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9. An Interlaboratory Comparison on the Characterization of a Sub-micrometer Polydisperse Particle Dispersion

Author

Benkstein, Kurt D., Balakrishnan, Gurusamy, Bhirde, Ashwinkumar, Chalus, Pascal, Das, Tapan K., Do, Ngoc, Duewer, David L., Filonov, Nazar, Cheong, Fook Chiong, Garidel, Patrick, Gill, Nicole S., Grabarek, Adam D., Grier, David G., Hadley, Judith, Hollingsworth, Andrew D., Howard, Wesley W., Jarzębski, Maciej, Jiskoot, Wim, Kar, Sambit R., Kestens, Vikram, Khasa, Harshit, Kim, Yoen Joo, Koulov, Atanas, Matter, Anja, Philips, Laura A., Probst, Christine, Ramaye, Yannic, Randolph, Theodore W., Ripple, Dean C., Romeijn, Stefan, Saggu, Miguel, Schleinzer, Franziska, Snell, Jared R., Tatarkiewicz, Jan “Kuba”, Wright, Heather Anne, and Yang, Dennis T.

Published
2022
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10. A methodological framework for mapping and assessment of ecosystem services provided by the natural heritage in Bulgaria

Author

Stoyan Nedkov, Bilyana Borisova, Mariyana Nikolova, Miglena Zhiyanski, Stelian Dimitrov, Radenka Mitova, Boian Koulov, Desislava Hristova, Hristina Prodanova, Lidiya Semerdzhieva, Yonko Dodev, Ivo Ihtimanski, and Velimira Stoyanova

Subjects
indicators, natural capital, recreation, tiers, to, Geography (General), G1-922
Abstract

Natural heritage (NH) includes natural features that can be described as outstanding universal value at a national level. It refers to the importance of ecosystems, biodiversity, and geodiversity for their existence value, and the ecosystems can be considered as the spatial units for its mapping and assessment. The ecosystem services (ES) concept provides an appropriate basis in the form of assessment and mapping methods that enable linking the state of ecosystems with human well-being. Thus, it can be used as a platform to find solutions to the problems related to the conflicts between conservation and the use of the NH. In this paper, we aim to present the process of developing a methodological framework for mapping and assessment of ecosystem services provided by the natural heritage in Bulgaria for recreation and tourism. The conceptual framework of the ecosystem-based assessment of NH in Bulgaria is based on the assumption that the generation of NH for the needs of tourism can be presented as the linkages between the natural systems and tourism in the form of ES potential, flow, and demand. The results demonstrate that the NH can be presented as a spatial phenomenon conceptualized by the flows of benefits from ecosystems to people which contribute to human well-being. The mapping and assessment procedures are fully developed for application at a national level, while for the regional and local level, few pilot studies mark some basic foundations for further development.

Published
2021
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26. Towards integrated mapping and assessment of ecosystems and their services in Bulgaria: The Central Balkan case study

Author

Stoyan Nedkov, Bilyana Borisova, Boian Koulov, Miglena Zhiyanski, Svetla Bratanova-Doncheva, Mariyana Nikolova, and Julia Kroumova

Subjects
Integrated assessment, economic valuation, floo, Ecology, QH540-549.5
Abstract

The aim of the EU Biodiversity Strategy to 2020 isto maintain and enhance ecosystem services (ES) in Europe and requires all Member States to map and assess the state of ecosystems and their services in the respective national territories. The EU-funded project ESMERALDA analyses ES mapping and assessment methods and approaches in their biophysical, social and economical perspectives, as well as their application in different case studies. The project also aims at the development of an integrated and consistent assessment framework. In Bulgaria, methodological guides for evaluation and mapping of the services provided by the nine main types of ecosystems have been prepared together with the respective proposals for their implementation in the national assessment. The Bulgarian research team analyses and tests various aspects of ecosystem services mapping and assessment, such as alternative economic assessments, multi-criteria analyses and biophysical assessment approaches, mapping challenges and local population surveys. In this paper paper, we review the ES activities in Bulgaria and present selected mapping and assessment methods tested in the Central Balkan case study area. It provides relevant examples for the implementation of integrated mapping and assessment of ecosystem services at local and regional level, where different mapping approaches and techniques are embedded within diverse policy contexts. The main goal of the study is to investigate how the assessment results can support the integration of the ecological functions of the Central Balkan National Park with the economic opportunities that it creates for the local and regional communities. A tiered approach has been used to organise the mapping and assessment exercises in the study area, in order to meet the needs for integrated ecosystem assessment and overcome the limitations of data availability. At tier 1, the study performs identification and initial ES mapping of the whole area. At tier 2, it applies economic valuation for the Municipality of Karlovo by using statistical data and the contingent valuation method. At tier 3, the investigation applies modelling methods to assess carbon storage and flood regulation on a larger scale. The results are presented in the form of maps at all levels, which use a uniform 0 to 5 assessment scale. The integrated approach presented here ensures a clear communication of the end results to the respective decision-makers.

Published
2018
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32. GIS-based Valuation of Ecosystem Services in Mountain Regions: A Case Study of the Karlovo Municipality in Bulgaria

Author

Boian Koulov, Ekaterina Ivanova, Bilyana Borisova, Assen Assenov, and Aleksandra Ravnachka

Subjects
ecosystem services mapping and valuation, ecosy, Ecology, QH540-549.5
Abstract

This study aims to apply approaches, methods, and indicators from the conceptual framework of ecosystem services valuation to a real world, local level case study. It tests a GIS-based mapping and valuation of ecosystem services model in a typical mountain municipality in Bulgaria. Investigation results address opportunities, challenges and limitations in the practical application of the ecosystem services concept. They include an integrated assessment of the ecosystem services in a specific administrative territorial unit and suggest its Total Economic Value. The introduction of the term “ecosystem services dysergy” should contribute to valuation theory and practice. The study upgrades the currently available knowledge base that supports geospatial planning and sustainable development of the Karlovo Municipality and offers recommendations for improvement of the municipal ecosystem services utilization, which include identification, analysis, and visualization of hotspots and dysergy areas.

Published
2017
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37. Subvisible (2–100 μm) particle analysis during biotherapeutic drug product development: Part 2, experience with the application of subvisible particle analysis

Author

Corvari, Vincent, Narhi, Linda O., Spitznagel, Thomas M., Afonina, Nataliya, Cao, Shawn, Cash, Patricia, Cecchini, Irene, DeFelippis, Michael R., Garidel, Patrick, Herre, Andrea, Koulov, Atanas V., Lubiniecki, Tony, Mahler, Hanns-Christian, Mangiagalli, Paolo, Nesta, Douglas, Perez-Ramirez, Bernardo, Polozova, Alla, Rossi, Mara, Schmidt, Roland, Simler, Robert, Singh, Satish, Weiskopf, Andrew, and Wuchner, Klaus

Published
2015
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40. Subvisible (2-100 μm) Particle Analysis During Biotherapeutic Drug Product Development: Part 1, Considerations and Strategy

Author

Narhi, Linda O., Corvari, Vincent, Ripple, Dean C., Afonina, Nataliya, Cecchini, Irene, Defelippis, Michael R., Garidel, Patrick, Herre, Andrea, Koulov, Atanas V., Lubiniecki, Tony, Mahler, Hanns-Christian, Mangiagalli, Paolo, Nesta, Douglas, Perez-Ramirez, Bernardo, Polozova, Alla, Rossi, Mara, Schmidt, Roland, Simler, Robert, Singh, Satish, Spitznagel, Thomas M., Weiskopf, Andrew, and Wuchner, Klaus

Published
2015
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41. Природни бедствия и политики за опазване на околната среда през XXI век

Author

Stoyanova, Velimira, Koulov, Boian, Borisova, Bilyana, and Rachev, Nikolay

Subjects
FOS: Earth and related environmental sciences
Abstract

В статията е изяснена същността на понятията опасност и бедствие, направен е преглед на природните бедствия, политиките за опазване на околната среда от началото на XXI в. и са представени резултатите по Националната научна програма „Опазване на околната среда и намаляване на риска от неблагоприятни явления и природни бедствия“ за периода 2019–2022 г. Наблюдава се увеличаване на честотата и загубите при проява на неблагоприятни природни явления в глобален мащаб. В Стокхолм, Швеция, през 1972 г. е приета Декларацията за околна среда – първият международен договор за екологични защита на Земята. Основни предизвикателства за България при изпълнението на политиката и законодателството на ЕС в областта на околната среда са: подобряване на качеството на въздуха; осигуряване на правилното събиране и пречистване на градските отпадъчни води; приемане на всеобхватна програма относно политиката в областта на кръговата икономика, опазване, съхранение и увеличаване на природния капитал, правилно изпълнение на законодателството за опазване на природата и мн. др., Problems of Geography, 2023, Vol.1-2, p. 107-129

Published
2023
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42. Identification of an Oxidizing Leachable from a Clinical Syringe Rubber Stopper

Author

Sonja Peter, Atanas Koulov, Andreas Zerr, Ombeline Danton, Hanns-Christian Mahler, Michael Jahn, Ariane Schröter, Pascal Chalus, and Jörg Huwyler

Subjects
Pharmaceutical Science, 02 engineering and technology, 030226 pharmacology & pharmacy, Chemical reaction, Ferrous, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Natural rubber, Oxidizing agent, Sample preparation, Drug Packaging, Dichloromethane, chemistry.chemical_classification, Chromatography, Syringes, Polymer, 021001 nanoscience & nanotechnology, chemistry, Leaching (chemistry), visual_art, visual_art.visual_art_medium, Rubber, Drug Contamination, 0210 nano-technology, Oxidation-Reduction
Abstract

Leaching of toxic or reactive chemicals from polymeric materials can adversely affect the quality and safety of biopharmaceuticals. It was therefore the aim of the present study to analyze leachables from a disposable clinical administration syringe using a polysorbate-containing surrogate solution and to assess their chemical reactivity. Analytical methods did include (headspace) GC-MS, Fourier-transform-infrared spectroscopy, a ferrous oxidation-xylenol orange assay, and nuclear magnetic resonance analysis. In the syringe leachables solution, the carcinogenic 1,1,2,2-tetrachloroethane (TCE) was detected in concentrations above the ICH M7-derived analytical evaluation threshold. TCE was shown to be an oxidation product of dichloromethane used during sample preparation. Since TCE was only isolated from incubations with the contained rubber stopper, we hypothesized that a stopper-derived leachable acted as a reactive oxidant promoting this chemical reaction. Subsequently, the leachable was identified to be the polymerization initiator Luperox® 101. Combining different analytical approaches led to the structural elucidation of a chemical reactive oxidant, which has the potential to interact and alter drug products. We conclude that chemically reactive compounds, such as the newly identified rubber stopper leachable Luperox® 101, may be of concern and therefore should be routinely considered if a prolonged exposure of polymers with drug products can be anticipated.

Published
2021

43. 4-Hydroxynonenal – A Toxic Leachable from Clinically Used Administration Materials

Author

Ariane Schröter, Hanns-Christian Mahler, Michael Jahn, Atanas Koulov, Jörg Huwyler, and Nadia Ben Sayed

Subjects
Aldehydes, Chromatography, Polymers, Pharmaceutical Science, 02 engineering and technology, 021001 nanoscience & nanotechnology, 030226 pharmacology & pharmacy, 4-Hydroxynonenal, Kinetics, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, chemistry, Drug product, 0210 nano-technology, Derivatization
Abstract

Introduction: The migration of chemicals from processing materials into biopharmaceuticals can lead to various problems. Leachables from administration materials, with no possibility of further clearance, are of particular concern. Released chemicals can be toxic or react with formulation components, thereby impacting product safety. Therapeutic proteins, which are susceptible to chemical modifications, have highest risk to be affected. Aim: The aim of this study was to identify a previously unknown leachable compound from clinical administration sets, which was present above the applied generic safety threshold. Methods: Extracts of commonly used clinical administration sets were analyzed using a recently established specific assay allowing the identification and quantification of the α,β-unsaturated aldehyde 4-hydroxynonenal (HNE) in a drug product surrogate solution. HNE was quantified after derivatization with 2,4-dinitrophenylhydrazine (DNPH) and liquid extraction of the formed hydrazone by LC-MRM analysis. Results: Potentially genotoxic HNE was a leachable compound from all tested administration sets, in parts exceeding safety thresholds for genotoxicants. The HNE-releasing polymer was identified as PVC. Conclusion: Clinical administration sets should be, like manufacturing materials and container closure systems, in the focus of routine leachables studies. Manufacturers of clinical administration sets should show responsibility to avoid the presence of safety concerning chemicals, like HNE.

Published
2021

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