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Abstract: Background. Various electrofusion parameters have to be adjusted to obtain theoptimal electrofusion efficiency. Based on published data, good electrofusion conditions can be achieved with the hypotonic treatment. However, the duration of the hypotonic treatment before electroporation and buffer hypoosmolarity have to be adjusted in order to cause cell swelling, to avoid regulatory volume decrease and to preserve cell viability. The aims of our study were to determine cell size dynamics and viability of four different cell lines in hypotonic buffer and to study the influence of the electroporation on the selected cell line in hypotonic buffer. Materials and methods. Cell size dynamics of different cell lines exposed to hypotonic buffer and electroporation were analyzed by time-resolvedcell size measurements. The viability of hypotonically treated oržand electroporated cells was determined 24 h after the experiment by a modified crystal violet (CV) viability assay. Results. In our experimental conditions the hypotonic treatment at 100 mOsm was efficient for CHO, V79 and B16-F1 cell lines. The optimal duration of the treatment was between two and five minutes. On the other hand the same hypotonic treatment did not cause cell swelling of NS1 cells. Cell swelling was also observed after electroporation of B16-F1 in isotonic buffer and it was amplified when hypotonic buffer was used. In addition, the regulatory volume decrease was successfully inhibited with electroporation. Conclusions. Cell size dynamicsin hypotonic conditions should be studied for each cell line since they differ in their sensitivity to the hypotonic treatment. The inhibition of cell regulatory volume decrease by electroporation may be beneficial in achieving higher electrofusion efficiency. (Abstract truncated at 2000 characters)
Keywords: hypotonic treatment, cell swelling, regulatory volume decrease, cell size measurements, viability, electrofusion, electroporation
Published in DiRROS: 08.03.2024; Views: 117; Downloads: 35
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Abstract: Wood resources have been essential for human welfare throughout history. Also nowadays, the volume of growing stock (GS) is considered one of the most important forest attributes monitored by National Forest Inventories (NFIs) to inform policy decisions and forest management planning. The origins of forest inventories closely relate to times of early wood shortage in Europe causing the need to explore and plan the utilisation of GS in the catchment areas of mines, saltworks and settlements. Over time, forest surveys became more detailed and their scope turned to larger areas, although they were still conceived as stand-wise inventories. In the 1920s, the first sample-based NFIs were introduced in the northern European countries. Since the earliest beginnings, GS monitoring approaches have considerably evolved. Current NFI methods differ due to country-specific conditions, inventory traditions, and information needs. Consequently, GS estimates were lacking international comparability and were therefore subject to recent harmonisation efforts to meet the increasing demand for consistent forest resource information at European level. As primary large-area monitoring programmes in most European countries, NFIs assess a multitude of variables, describing various aspects of sustainable forest management, including for example wood supply, carbon sequestration, and biodiversity. Many of these contemporary subject matters involve considerations about GS and its changes, at different geographic levels and time frames from past to future developments according to scenario simulations. Due to its historical, continued and currently increasing importance, we provide an up-to-date review focussing on large-area GS monitoring where we i) describe the origins and historical development of European NFIs, ii) address the terminology and present GS definitions of NFIs, iii) summarise the current methods of 23 European NFIs including sampling methods, tree measurements, volume models, estimators, uncertainty components, and the use of air- and space-borne data sources, iv) present the recent progress in NFI harmonisation in Europe, and v) provide an outlook under changing climate and forest-based bioeconomy objectives.
Keywords: forest history, natural resources, sustainability, timber volume, sampling, remote sensing, bioeconomy, climate change
Published in DiRROS: 14.12.2021; Views: 776; Downloads: 552
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Abstract: This paper presents the growth potential of sycamore (Acer pseudoplatanus L.) on four types of forest sites located on carbonate bedrock. The research covers sycamore sites (Aceri-Fraxinetum ill.), beech sites (Lamio orvalae-Fagetum), beech sites planted with Norway spruce, and silver fir-beechsites (Omphalodo-Fagetum aceretosum). The analyses for each forest type were carried out on five plots. Our aim was to determine the effect of site factors and stand parameters on sycamore growth. Site productivity (SP) is positively correlated with soil depth, coarse silt percentage in the cambichorizon, the content of phosphorus in leaves and, partly, with potassium. The effect of nitrogen supply on height growth or SP was not confirmed. Furthermore, height growth on sites with a higher rate of nutrient cycling, higher macronutrient supply and higher sand percentage in the cambic horizon is significantly faster. As to the growth of basal area, in addition to positive dependences of crown size, many other correlations with site factors were confirmed.
Keywords: beech stand, growing stock, stand value, current volume increment, current value increment, quality structure, social collective
Published in DiRROS: 12.07.2017; Views: 4431; Downloads: 1816
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